National Library of Energy BETA

Sample records for thick plywood roughly

  1. Does surface roughness amplify wetting?

    SciTech Connect (OSTI)

    Malijevský, Alexandr

    2014-11-14

    Any solid surface is intrinsically rough on the microscopic scale. In this paper, we study the effect of this roughness on the wetting properties of hydrophilic substrates. Macroscopic arguments, such as those leading to the well-known Wenzel's law, predict that surface roughness should amplify the wetting properties of such adsorbents. We use a fundamental measure density functional theory to demonstrate the opposite effect from roughness for microscopically corrugated surfaces, i.e., wetting is hindered. Based on three independent analyses we show that microscopic surface corrugation increases the wetting temperature or even makes the surface hydrophobic. Since for macroscopically corrugated surfaces the solid texture does indeed amplify wetting there must exist a crossover between two length-scale regimes that are distinguished by opposite response on surface roughening. This demonstrates how deceptive can be efforts to extend the thermodynamical laws beyond their macroscopic territory.

  2. Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet), Building America Case Study: Technology Solutions for New and Existing Homes, Building Technologies Office (BTO)

    Energy Savers [EERE]

    Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing PROJECT aPPliCaTiON Construction: Existing homes with unvented cathedralized roofs. Type: Residential Climate Zones: All TEam mEmbERs Building Science Corporation www.buildingscience.com BASF www.basf.com Dow Chemical Company www.dow.com Honeywell http://honeywell.com Icynene www.icynene.com COdE COmPliaNCE 2012 International Code Council, International Residential Code Spray polyurethane foams (SPFs) have advantages over

  3. Electrokinetic transport in microchannels with random roughness

    SciTech Connect (OSTI)

    Wang, Moran [Los Alamos National Laboratory; Kang, Qinjun [Los Alamos National Laboratory

    2008-01-01

    We present a numerical framework to model the electrokinetic transport in microchannels with random roughness. The three-dimensional microstructure of the rough channel is generated by a random generation-growth method with three statistical parameters to control the number density, the total volume fraction, and the anisotropy characteristics of roughness elements. The governing equations for the electrokinetic transport are solved by a high-efficiency lattice Poisson?Boltzmann method in complex geometries. The effects from the geometric characteristics of roughness on the electrokinetic transport in microchannels are therefore modeled and analyzed. For a given total roughness volume fraction, a higher number density leads to a lower fluctuation because of the random factors. The electroosmotic flow rate increases with the roughness number density nearly logarithmically for a given volume fraction of roughness but decreases with the volume fraction for a given roughness number density. When both the volume fraction and the number density of roughness are given, the electroosmotic flow rate is enhanced by the increase of the characteristic length along the external electric field direction but is reduced by that in the direction across the channel. For a given microstructure of the rough microchannel, the electroosmotic flow rate decreases with the Debye length. It is found that the shape resistance of roughness is responsible for the flow rate reduction in the rough channel compared to the smooth channel even for very thin double layers, and hence plays an important role in microchannel electroosmotic flows.

  4. Roughness Optimization at High Modes for GDP CHx Microshells

    SciTech Connect (OSTI)

    Theobald, M.; Dumay, B.; Chicanne, C.; Barnouin, J.; Legaie, O.; Baclet, P.

    2004-03-15

    For the ''Megajoule'' Laser (LMJ) facility of the CEA, amorphous hydrogenated carbon (a-C:H) is the nominal ablator to be used for inertial confinement fusion (ICF) experiments. These capsules contain the fusible deuterium-tritium mixture to achieve ignition. Coatings are prepared by glow discharge polymerization (GDP) with trans-2-butene and hydrogen. The films properties have been investigated. Laser fusion targets must have optimized characteristics: a diameter of about 2.4 mm for LMJ targets, a thickness up to 175 {mu}m, a sphericity and a thickness concentricity better than 99% and an outer and an inner roughness lower than 20 nm at high modes. The surface finish of these laser fusion targets must be extremely smooth to minimize hydrodynamic instabilities.Movchan and Demchishin, and later Thornton introduced a structure zone model (SZM) based on both evaporated and sputtered metals. They investigated the influence of base temperature and the sputtering gas pressure on structure and properties of thick polycrystalline coatings of nickel, titanium, tungsten, aluminum oxide. An original cross-sectional analysis by atomic force microscopy (AFM) allows amorphous materials characterization and permits to make an analogy between the amorphous GDP material and the existing model (SZM). The purpose of this work is to understand the relationship between the deposition parameters, the growing structures and the surface roughness.The coating structure as a function of deposition parameters was first studied on plane silicon substrates and then optimized on PAMS shells. By adjusting the coating parameters, the structures are modified, and in some case, the high modes roughness decreases dramatically.

  5. Surface roughness and interface width scaling of magnetron sputter deposited Ni/Ti multilayers

    SciTech Connect (OSTI)

    Maidul Haque, S.; Biswas, A.; Tokas, R. B.; Bhattacharyya, D.; Sahoo, N. K.; Bhattacharya, Debarati

    2013-09-14

    Using an indigenously built r.f. magnetron sputtering system, several single layer Ti and Ni films have been deposited at varying deposition conditions. All the samples have been characterized by Grazing Incidence X-ray Reflectivity (GIXR) and Atomic Force Microscopy to estimate their thickness, density, and roughness and a power law dependence of the surface roughness on the film thickness has been established. Subsequently, at optimized deposition condition of Ti and Ni, four Ni/Ti multilayers of 11-layer, 21-layer, 31-layer, and 51-layer having different bilayer thickness have been deposited. The multilayer samples have been characterized by GIXR and neutron reflectivity measurements and the experimental data have been fitted assuming an appropriate sample structure. A power law correlation between the interface width and bilayer thickness has been observed for the multilayer samples, which was explained in the light of alternate roughening/smoothening of multilayers and assuming that at the interface the growth restarts every time.

  6. Thick film hydrogen sensor

    DOE Patents [OSTI]

    Hoffheins, B.S.; Lauf, R.J.

    1995-09-19

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors. 8 figs.

  7. Thick film hydrogen sensor

    DOE Patents [OSTI]

    Hoffheins, Barbara S. (Knoxville, TN); Lauf, Robert J. (Oak Ridge, TN)

    1995-01-01

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors.

  8. Rough surface reconstruction for ultrasonic NDE simulation

    SciTech Connect (OSTI)

    Choi, Wonjae; Shi, Fan; Lowe, Michael J. S.; Skelton, Elizabeth A.; Craster, Richard V.

    2014-02-18

    The reflection of ultrasound from rough surfaces is an important topic for the NDE of safety-critical components, such as pressure-containing components in power stations. The specular reflection from a rough surface of a defect is normally lower than it would be from a flat surface, so it is typical to apply a safety factor in order that justification cases for inspection planning are conservative. The study of the statistics of the rough surfaces that might be expected in candidate defects according to materials and loading, and the reflections from them, can be useful to develop arguments for realistic safety factors. This paper presents a study of real rough crack surfaces that are representative of the potential defects in pressure-containing power plant. Two-dimensional (area) values of the height of the roughness have been measured and their statistics analysed. Then a means to reconstruct model cases with similar statistics, so as to enable the creation of multiple realistic realizations of the surfaces, has been investigated, using random field theory. Rough surfaces are reconstructed, based on a real surface, and results for these two-dimensional descriptions of the original surface have been compared with those from the conventional model based on a one-dimensional correlation coefficient function. In addition, ultrasonic reflections from them are simulated using a finite element method.

  9. Surface roughness effects on the solar reflectance of cool asphalt...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Surface roughness effects on the solar reflectance of cool asphalt shingles Citation Details In-Document Search Title: Surface roughness effects on the solar ...

  10. Tensile cracking of a brittle conformal coating on a rough substrate

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Reedy, Jr., E. D.

    2016-04-07

    This note examines the effect of interfacial roughness on the initiation and growth of channel cracks in a brittle film. A conformal film with cusp-like surface flaws that replicate the substrate roughness is investigated. This type of surface flaw is relatively severe in the sense that stress diverges as the cusp-tip is approached (i.e., there is a power-law stress singularity). For the geometry and range of film properties considered, the analysis suggests that smoothing the substrate could substantially increase the film’s resistance to the formation of the through-the-thickness cracks that precede channel cracking. Furthermore, smoothing the substrate’s surface has amore » relatively modest effect on the film stress needed to propagate a channel crack.« less

  11. Laser detection of material thickness

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM)

    2002-01-01

    There is provided a method for measuring material thickness comprising: (a) contacting a surface of a material to be measured with a high intensity short duration laser pulse at a light wavelength which heats the area of contact with the material, thereby creating an acoustical pulse within the material: (b) timing the intervals between deflections in the contacted surface caused by the reverberation of acoustical pulses between the contacted surface and the opposite surface of the material: and (c) determining the thickness of the material by calculating the proportion of the thickness of the material to the measured time intervals between deflections of the contacted surface.

  12. Counterintuitive MCNPX Results for Scintillator Surface Roughness Effect

    SciTech Connect (OSTI)

    2012-08-12

    We have reported on our recent MCNPX simulation results of energy deposition for a group of 8 scintillation detectors, coupled with various rough surface patterns. The MCNPX results generally favored the detectors with various rough surface patterns. The observed MCNPX results are not fully explained by this work.

  13. System for measuring film thickness

    DOE Patents [OSTI]

    Batishko, Charles R.; Kirihara, Leslie J.; Peters, Timothy J.; Rasmussen, Donald E.

    1990-01-01

    A system for determining the thicknesses of thin films of materials exhibiting fluorescence in response to exposure to excitation energy from a suitable source of such energy. A section of film is illuminated with a fixed level of excitation energy from a source such as an argon ion laser emitting blue-green light. The amount of fluorescent light produced by the film over a limited area within the section so illuminated is then measured using a detector such as a photomultiplier tube. Since the amount of fluorescent light produced is a function of the thicknesses of thin films, the thickness of a specific film can be determined by comparing the intensity of fluorescent light produced by this film with the intensity of light produced by similar films of known thicknesses in response to the same amount of excitation energy. The preferred embodiment of the invention uses fiber optic probes in measuring the thicknesses of oil films on the operational components of machinery which are ordinarily obscured from view.

  14. Tube wall thickness measurement apparatus

    DOE Patents [OSTI]

    Lagasse, P.R.

    1985-06-21

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and radius by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

  15. Tube wall thickness measurement apparatus

    DOE Patents [OSTI]

    Lagasse, Paul R.

    1987-01-01

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and circumference by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

  16. Eddy current thickness measurement apparatus

    DOE Patents [OSTI]

    Rosen, Gary J.; Sinclair, Frank; Soskov, Alexander; Buff, James S.

    2015-06-16

    A sheet of a material is disposed in a melt of the material. The sheet is formed using a cooling plate in one instance. An exciting coil and sensing coil are positioned downstream of the cooling plate. The exciting coil and sensing coil use eddy currents to determine a thickness of the solid sheet on top of the melt.

  17. High Temperature Superconducting Thick Films

    DOE Patents [OSTI]

    Arendt, Paul N.; Foltyn, Stephen R.; Groves, James R.; Holesinger, Terry G.; Jia, Quanxi

    2005-08-23

    An article including a substrate, a layer of an inert oxide material upon the surface of the substrate, (generally the inert oxide material layer has a smooth surface, i.e., a RMS roughness of less than about 2 nm), a layer of an amorphous oxide or oxynitride material upon the inert oxide material layer, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the amorphous oxide material layer is provided together with additional layers such as at least one layer of a buffer material upon the oriented cubic oxide material layer or a HTS top-layer of YBCO directly upon the oriented cubic oxide material layer. With a HTS top-layer of YBCO upon at least one layer of a buffer material in such an article, Jc's of 1.4×106 A/cm2 have been demonstrated with projected Ic's of 210 Amperes across a sample 1 cm wide.

  18. High Temperature Superconducting Thick Films

    DOE Patents [OSTI]

    Arendt, Paul N. (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM); Groves, James R. (Los Alamos, NM); Holesinger, Terry G. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

    2005-08-23

    An article including a substrate, a layer of an inert oxide material upon the surface of the substrate, (generally the inert oxide material layer has a smooth surface, i.e., a RMS roughness of less than about 2 nm), a layer of an amorphous oxide or oxynitride material upon the inert oxide material layer, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the amorphous oxide material layer is provided together with additional layers such as at least one layer of a buffer material upon the oriented cubic oxide material layer or a HTS top-layer of YBCO directly upon the oriented cubic oxide material layer. With a HTS top-layer of YBCO upon at least one layer of a buffer material in such an article, Jc's of 1.4106 A/cm2 have been demonstrated with projected Ic's of 210 Amperes across a sample 1 cm wide.

  19. ANALYZING SURFACE ROUGHNESS DEPENDENCE OF LINEAR RF LOSSES

    SciTech Connect (OSTI)

    Reece, Charles E.; Kelley, Michael J.; Xu, Chen

    2012-09-01

    Topographic structure on Superconductivity Radio Frequency (SRF) surfaces can contribute additional cavity RF losses describable in terms of surface RF reflectivity and absorption indices of wave scattering theory. At isotropic homogeneous extent, Power Spectrum Density (PSD) of roughness is introduced and quantifies the random surface topographic structure. PSD obtained from different surface treatments of niobium, such Buffered Chemical Polishing (BCP), Electropolishing (EP), Nano-Mechanical Polishing (NMP) and Barrel Centrifugal Polishing (CBP) are compared. A perturbation model is utilized to calculate the additional rough surface RF losses based on PSD statistical analysis. This model will not consider that superconductor becomes normal conducting at fields higher than transition field. One can calculate the RF power dissipation ratio between rough surface and ideal smooth surface within this field range from linear loss mechanisms.

  20. Tuning the thickness of electrochemically grafted layers in large area molecular junctions

    SciTech Connect (OSTI)

    Fluteau, T.; Bessis, C.; Barraud, C. Della Rocca, M. L.; Lafarge, P.; Martin, P.; Lacroix, J.-C.

    2014-09-21

    We have investigated the thickness, the surface roughness, and the transport properties of oligo(1-(2-bisthienyl)benzene) (BTB) thin films grafted on evaporated Au electrodes, thanks to a diazonium-based electro-reduction process. The thickness of the organic film is tuned by varying the number of electrochemical cycles during the growth process. Atomic force microscopy measurements reveal the evolution of the thickness in the range of 227 nm. Its variation displays a linear dependence with the number of cycles followed by a saturation attributed to the insulating behavior of the organic films. Both ultrathin (2 nm) and thin (12 and 27 nm) large area BTB-based junctions have then been fabricated using standard CMOS processes and finally electrically characterized. The electronic responses are fully consistent with a tunneling barrier in case of ultrathin BTB film whereas a pronounced rectifying behavior is reported for thicker molecular films.

  1. Surface and Interface Properties of 1012 Unit Cells Thick Sputter Deposited Epitaxial CeO2Films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Saraf, L. V.; Wang, C. M.; Engelhard, M. H.; Nachimuthu, P.

    2008-01-01

    Ultrathin and continuous epitaxial films with relaxed lattice strain can potentially maintain more of its bulk physical and chemical properties and are useful as buffer layers. We study surface, interface, and microstructural properties of ultrathin (?1012 unit cells thick) epitaxial ceria films grown on single crystal YSZ substrates. The out-of -plane and in-plane lattice parameters indicate relaxation in the continuous film due to misfit dislocations seen by high-resolution transmission electron microscopy (HRTEM) and substrate roughness of?1-2 unit cells, confirmed by atomic force microscopy and HRTEM. A combination of secondary sputtering, lattice mismatch, substrate roughness, and surface reduction creating secondary phasemorewas likely the cause of surface roughness which should be reduced to a minimum level for effective use of it as buffer layers.less

  2. Surface and Interface Properties of 10–12 Unit Cells Thick Sputter Deposited Epitaxial CeO 2 Films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Saraf, L. V.; Wang, C. M.; Engelhard, M. H.; Nachimuthu, P.

    2008-01-01

    Ulmore » trathin and continuous epitaxial films with relaxed lattice strain can potentially maintain more of its bulk physical and chemical properties and are useful as buffer layers. We study surface, interface, and microstructural properties of ultrathin ( ∼ 10–12 unit cells thick) epitaxial ceria films grown on single crystal YSZ substrates. The out-of -plane and in-plane lattice parameters indicate relaxation in the continuous film due to misfit dislocations seen by high-resolution transmission electron microscopy (HRTEM) and substrate roughness of ∼ 1-2 unit cells, confirmed by atomic force microscopy and HRTEM. A combination of secondary sputtering, lattice mismatch, substrate roughness, and surface reduction creating secondary phase was likely the cause of surface roughness which should be reduced to a minimum level for effective use of it as buffer layers.« less

  3. Experimental study of laser-oxygen cutting of low-carbon steel using fibre and CO{sub 2} lasers under conditions of minimal roughness

    SciTech Connect (OSTI)

    Golyshev, A A; Malikov, A G; Orishich, A M; Shulyatyev, V B

    2014-10-31

    The results of an experimental study of laser-oxygen cutting of low-carbon steel using fibre and CO{sub 2} lasers are generalised. The dependence of roughness of the cut surface on the cutting parameters is investigated, and the conditions under which the surface roughness is minimal are formulated. It is shown that for both types of lasers these conditions can be expressed in the same way in terms of the dimensionless variables – the Péclet number Pe and the output power Q of laser radiation per unit thickness of the cut sheet – and take the form of the similarity laws: Pe = const, Q = const. The optimal values of Pe and Q are found. We have derived empirical expressions that relate the laser power and cutting speed with the thickness of the cut sheet under the condition of minimal roughness in the case of cutting by means of radiation from fibre and CO{sub 2} lasers. (laser technologies)

  4. Turbine airfoil with outer wall thickness indicators

    DOE Patents [OSTI]

    Marra, John J; James, Allister W; Merrill, Gary B

    2013-08-06

    A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

  5. A Thick Target for Synchrotrons and Betatrons

    DOE R&D Accomplishments [OSTI]

    McMillan, E. M.

    1950-09-19

    If a wide x-ray beam from an electron synchrotron or betatron is desired, in radiographic work with large objects for example, the usually very thin target may be replaced by a thick one, provided the resulting distortion of the x-ray spectrum due to multiple radiative processes is permissible. It is difficult to make the circulating electron beam traverse a thick target directly because of the small spacing between successive turns. Mounting a very thin beryllium, or other low-z material, fin on the edge of the thick target so that the fin projects into the beam will cause the beam to lose sufficient energy, and therefore radium, to strike the thick target the next time around. Sample design calculations are given.

  6. Thick crystalline films on foreign substrates

    DOE Patents [OSTI]

    Smith, Henry I.; Atwater, Harry A.; Geis, Michael W.

    1986-01-01

    To achieve a uniform texture, large crystalline grains or, in some cases, a single crystalline orientation in a thick (>1 .mu.m) film on a foreign substrate, the film is formed so as to be thin (<1 .mu.m) in a certain section. Zone-melting recrystallization is initiated in the thin section and then extended into the thick section. The method may employ planar constriction patterns of orientation filter patterns.

  7. Thick crystalline films on foreign substrates

    DOE Patents [OSTI]

    Smith, H.I.; Atwater, H.A.; Geis, M.W.

    1986-03-18

    To achieve a uniform texture, large crystalline grains or, in some cases, a single crystalline orientation in a thick (>1 [mu]m) film on a foreign substrate, the film is formed so as to be thin (<1 [mu]m) in a certain section. Zone-melting recrystallization is initiated in the thin section and then extended into the thick section. The method may employ planar constriction patterns of orientation filter patterns. 2 figs.

  8. Characterization of thick 4H-SiC hot-wall CVD layers

    SciTech Connect (OSTI)

    Paisley, M.J.; Irvine, K.G.; Kordina, O.; Singh, R.; Palmour, J.W.; Carter, C.H. Jr.

    1999-07-01

    Epitaxial 4H-SiC layers suitable for high power devices have been grown in a hot-wall chemical-vapor deposition (CVD) system. These layers were subsequently characterized for many parameters important in device development and production. The uniformity of both thickness and doping is presented. Doping trends vs. temperature and growth rate is shown for the p-type dopant used. The n-type dopant drops in concentration with increasing temperature or increasing growth rate. In contrast, the p-type dopant increases in concentration with decreasing temperature or increasing growth rate. A simple descriptive model for this behavior is presented. The outcome from capacitance-voltage and SIMS measurements demonstrate that transitions from n to n{sup {minus}}, or p to p{sup {minus}}, and even n to p levels can be made quickly without adjustment to growth conditions. The ability to produce sharp transitions without process changes avoids degrading the resulting surface morphology or repeatability of the process. Avoiding process changes is particularly important in growth of thick layers since surface roughness tends to increase with layer thickness. Device results from diodes producing two different blocking voltages in excess of 5 kV is also shown. The higher voltage diodes exhibited a breakdown behavior which was near the theoretical limit for the epitaxial layer thickness and doping level grown.

  9. Pd conductor for thick film hydrogen sensor

    SciTech Connect (OSTI)

    Felten, J.J.; Hoffheins, B.S.; Lauf, R.J.

    1996-12-31

    Cooperation between a materials developer and sensor designers has resulted in a palladium conductor used ro design and build a new hydrogen sensor that has superior performance characteristics and is also inexpensive to manufacture. Material characteristics give it faster response time and greater thermal/mechanical stability. The thick film palladium conductor paste, which can be fired at 850{degrees}C-950{degrees}C, has provided device designers a practical conductor paste with which to produce the improved sensor. The conductor uses a high surface area Pd powder combined with a binder glass that is chemically very inert, which combination produces a porous conductor that has good adhesion and chemical resistance. The current sensor design consists of three or four thick film Layers. Because of the flexibility of thick film techniques, the sensor element can be configured to any desired size and shape for specific instrument needs.

  10. Wall thickness measuring method and apparatus

    DOE Patents [OSTI]

    Salzer, Leander J. (Los Alamos, NM); Bergren, Donald A. (Los Alamos, NM)

    1989-01-01

    An apparatus for measuring the wall thickness of a nonmagnetic article having a housing supporting a magnet and a contiguous supporting surface. The tubular article and the housing are releasably secured to the supporting surface and a support member of an optical comparator, respectively. To determine the wall thickness of the article at a selected point, a magnetically responsive ball is positioned within the tubular article over said point and retained therein by means of a magnetic field produced by the magnet. Thereafter, an optical comparator is employed to project a magnified image of the ball on a screen and the wall thickness at the selected point is calculated by using a ball surface measurement taken with the comparator in conjunction with a previously determined base line measurement.

  11. Wall thickness measuring method and apparatus

    DOE Patents [OSTI]

    Salzer, L.J.; Bergren, D.A.

    1987-10-06

    An apparatus for measuring the wall thickness of a nonmagnetic article having a housing supporting a magnet and a contiguous supporting surface. The tubular article and the housing are releasably secured to the supporting surface and a support member of an optical comparator, respectively. To determine the wall thickness of the article at a selected point, a magnetically responsive ball is positioned within the tubular article over said point and retained therein by means of a magnetic field produced by the magnet. Thereafter, an optical comparator is employed to project a magnified image of the ball on a screen and the wall thickness at the selected point is calculated by using a ball surface measurement taken with the comparator in conjunction with a previously determined base line measurement.

  12. Gas turbine bucket wall thickness control

    DOE Patents [OSTI]

    Stathopoulos, Dimitrios; Xu, Liming; Lewis, Doyle C.

    2002-01-01

    A core for use in casting a turbine bucket including serpentine cooling passages is divided into two pieces including a leading edge core section and a trailing edge core section. Wall thicknesses at the leading edge and the trailing edge of the turbine bucket can be controlled independent of each other by separately positioning the leading edge core section and the trailing edge core section in the casting die. The controlled leading and trailing edge thicknesses can thus be optimized for efficient cooling, resulting in more efficient turbine operation.

  13. Glue Film Thickness Measurements by Spectral Reflectance

    SciTech Connect (OSTI)

    B. R. Marshall

    2010-09-20

    Spectral reflectance was used to determine the thickness of thin glue layers in a study of the effect of the glue on radiance and reflectance measurements of shocked-tin substrates attached to lithium fluoride windows. Measurements based on profilometry of the components were found to be inaccurate due to flatness variations and deformation of the tin substrate under pressure during the gluing process. The accuracy of the spectral reflectance measurements were estimated to be ±0.5 μm, which was sufficient to demonstrate a convincing correlation between glue thickness and shock-generated light.

  14. Hot rolling of thick uranium molybdenum alloys

    SciTech Connect (OSTI)

    DeMint, Amy L.; Gooch, Jack G.

    2015-11-17

    Disclosed herein are processes for hot rolling billets of uranium that have been alloyed with about ten weight percent molybdenum to produce cold-rollable sheets that are about one hundred mils thick. In certain embodiments, the billets have a thickness of about 7/8 inch or greater. Disclosed processes typically involve a rolling schedule that includes a light rolling pass and at least one medium rolling pass. Processes may also include reheating the rolling stock and using one or more heavy rolling passes, and may include an annealing step.

  15. Stranski-Krastanow islanding initiated on the stochastic rough surfaces of the epitaxially strained thin films

    SciTech Connect (OSTI)

    Tarik Ogurtani, Omer; Celik, Aytac; Emre Oren, Ersin

    2014-06-14

    Quantum dots (QD) have discrete energy spectrum, which can be adjusted over a wide range by tuning composition, density, size, lattice strain, and morphology. These features make quantum dots attractive for the design and fabrication of novel electronic, magnetic and photonic devices and other functional materials used in cutting-edge applications. The formation of QD on epitaxially strained thin film surfaces, known as Stranski-Krastanow (SK) islands, has attracted great attention due to their unique electronic properties. Here, we present a systematic dynamical simulation study for the spontaneous evolution of the SK islands on the stochastically rough surfaces (nucleationless growth). During the development of SK islands through the mass accumulation at randomly selected regions of the film via surface drift-diffusion (induced by the capillary and mismatch stresses) with and/or without growth, one also observes the formation of an extremely thin wetting layer having a thickness of a few Angstroms. Above a certain threshold level of the mismatch strain and/or the size of the patch, the formation of multiple islands separated by shallow wetting layers is also observed as metastable states such as doublets even multiplets. These islands are converted into a distinct SK islands after long annealing times by coalescence through the long range surface diffusion. Extensive computer simulation studies demonstrated that after an initial transient regime, there is a strong quadratic relationship between the height of the SK singlet and the intensity of the lattice mismatch strain (in a wide range of stresses up to 8.5?GPa for germanium thin crystalline films), with the exception at those critical points where the morphological (shape change with necking) transition takes place.

  16. Heat Transfer and Friction-Factor Methods Turbulent Flow Inside Pipes 3d Rough

    Energy Science and Technology Software Center (OSTI)

    1994-01-21

    Three-dimensional roughened internally enhanced tubes have been shown to be one of the most energy efficient for turbulent, forced convection applications. However, there is only one prediction method presented in the open literature and that is restricted to three-dimensional sand-grain roughness. Other roughness types are being proposed: hemispherical sectors, truncated cones, and full and truncated pyramids. There are no validated heat-transfer and friction-factor prediction methods for these different roughness shapes that can be used inmore » the transition and fully rough region. This program calculates the Nusselt number and friction factor values, for a broad range of three-dimensional roughness types such as hemispherical sectors, truncated cones, and full and truncated pyramids. Users of this program are heat-exchangers designers, enhanced tubing suppliers, and research organizations or academia who are developing or validating prediction methods.« less

  17. A de Sitter tachyon thick braneworld

    SciTech Connect (OSTI)

    Germn, Gabriel; Herrera-Aguilar, Alfredo; Malagn-Morejn, Dagoberto; Mora-Luna, Refugio Rigel; Rocha, Roldo da E-mail: aha@fis.unam.mx E-mail: rigel@ifm.umich.mx

    2013-02-01

    Among the multiple 5D thick braneworld models that have been proposed in the last years, in order to address several open problems in modern physics, there is a specific one involving a tachyonic bulk scalar field. Delving into this framework, a thick braneworld with a cosmological background induced on the brane is here investigated. The respective field equations derived from the model with a warped 5D geometry are highly non-linear equations, admitting a non-trivial solution for the warp factor and the tachyon scalar field as well, in a de Sitter 4D cosmological background. Moreover, the non-linear tachyonic scalar field, that generates the brane in complicity with warped gravity, has the form of a kink-like configuration. Notwithstanding, the non-linear field equations restricting character does not allow one to easily find thick brane solutions with a decaying warp factor which leads to the localization of 4D gravity and other matter fields. We derive such a thick brane configuration altogether in this tachyon-gravity setup. When analyzing the spectrum of gravity fluctuations in the transverse traceless sector, the 4D gravity is shown to be localized due to the presence of a single zero mode bound state, separated by a continuum of massive Kaluza-Klein (KK) modes by a mass gap. It contrasts with previous results, where there is a KK massive bound excitation providing no clear physical interpretation. The mass gap is determined by the scale of the metric parameter H. Finally, the corrections to Newton's law in this model are computed and shown to decay exponentially. It is in full compliance to corrections reported in previous results (up to a constant factor) within similar braneworlds with induced 4D de Sitter metric, despite the fact that the warp factor and the massive modes have a different form.

  18. Influence of pitch, twist, and taper on a blade`s performance loss due to roughness

    SciTech Connect (OSTI)

    Tangler, J.L.

    1996-12-31

    The purpose of this study was to determine the influence of blade geometric parameters such as pitch, twist, and taper on a blade`s sensitivity to leading edge roughness. The approach began with an evaluation of available test data of performance degradation due to roughness effects for several rotors. In addition to airfoil geometry, this evaluation suggested that a rotor`s sensitivity to roughness was also influenced by the blade geometric parameters. Parametric studies were conducted using the PROP computer code with wind-tunnel airfoil characteristics for smooth and rough surface conditions to quantify the performance loss due to roughness for tapered and twisted blades relative to a constant-chord, non-twisted blade at several blade pitch angles. The results indicate that a constant-chord, non-twisted blade pitched toward stall will have the greatest losses due to roughness. The use of twist, taper, and positive blade pitch angles all help reduce the angle-of-attack distribution along the blade for a given wind speed and the associated performance degradation due to roughness. 8 refs., 6 figs.

  19. Method for preparing a thick film conductor

    DOE Patents [OSTI]

    Nagesh, Voddarahalli K.; Fulrath, deceased, Richard M.

    1978-01-01

    A method for preparing a thick film conductor which comprises providing surface active glass particles, mixing the surface active glass particles with a thermally decomposable organometallic compound, for example, a silver resinate, and then decomposing the organometallic compound by heating, thereby chemically depositing metal on the glass particles. The glass particle mixture is applied to a suitable substrate either before or after the organometallic compound is thermally decomposed. The resulting system is then fired in an oxidizing atmosphere, providing a microstructure of glass particles substantially uniformly coated with metal.

  20. Thickness measurement locations of mechanical integrity

    SciTech Connect (OSTI)

    Decker, J.R.; Rivas, N.

    1996-07-01

    This paper will describe the importance of establishing thickness measurement location (TNE) criteria. It will also seek to quantify the frequency of inspections and review the methods for establishing techniques to ensure reliability and repeatability of inspections at TMLs using qualified inspectors. Also discussed will be the most useful way to document the results of an inspection and how to effectively maintain consistency in the mechanical integrity program. It reviews different methods of inspection and uses lessons learned from in-service experience with numerous mechanical projects in the petrochemical industry. The importance of qualified inspectors, quality inspection, electronic data acquisition and electronic data storage will be discussed.

  1. Skin thickness effects on in vivo LXRF

    SciTech Connect (OSTI)

    Preiss, I.L.; Washington, W. II

    1995-12-31

    The analysis of lead concentration in bone utilizing LXRF can be adversely effected by overlying issue. A quantitative measure of the attenuation of the 10.5 keV Pb L a x-ray signal by skin and skin equivalent plastic has been conducted. Concentration ranges in plaster of Paris and goat bone from 7 to 90 ppm with attenuators of Lucite{reg_sign} and pig skin were examined. It is concluded that no quantitative or semi quantitative analysis can be achieved if overlying sue thickness exceeds 3 mm for Ph concentrations of less than 30 porn Ph in bone.

  2. Solid Deuterium-Tritium Surface Roughness In A Beryllium Inertial Confinement Fusion Shell

    SciTech Connect (OSTI)

    Kozioziemski, B J; Sater, J D; Moody, J D; Montgomery, D S; Gautier, C

    2006-04-19

    Solid deuterium-tritium (D-T) fuel layers for inertial confinement fusion experiments were formed inside of a 2 mm diameter beryllium shell and were characterized using phase-contrast enhanced x-ray imaging. The solid D-T surface roughness is found to be 0.4 {micro}m for modes 7-128 at 1.5 K below the melting temperature. The layer roughness is found to increase with decreasing temperature, in agreement with previous visible light characterization studies. However, phase-contrast enhanced x-ray imaging provides a more robust surface roughness measurement than visible light methods. The new x-ray imaging results demonstrate clearly that the surface roughness decreases with time for solid D-T layers held at 1.5 K below the melting temperature.

  3. Enhancement of vortex induced forces and motion through surface roughness control

    DOE Patents [OSTI]

    Bernitsas, Michael M.; Raghavan, Kamaldev

    2011-11-01

    Roughness is added to the surface of a bluff body in a relative motion with respect to a fluid. The amount, size, and distribution of roughness on the body surface is controlled passively or actively to modify the flow around the body and subsequently the Vortex Induced Forces and Motion (VIFM). The added roughness, when designed and implemented appropriately, affects in a predetermined way the boundary layer, the separation of the boundary layer, the level of turbulence, the wake, the drag and lift forces, and consequently the Vortex Induced Motion (VIM), and the fluid-structure interaction. The goal of surface roughness control is to increase Vortex Induced Forces and Motion. Enhancement is needed in such applications as harnessing of clean and renewable energy from ocean/river currents using the ocean energy converter VIVACE (Vortex Induced Vibration for Aquatic Clean Energy).

  4. Reduction of vortex induced forces and motion through surface roughness control

    DOE Patents [OSTI]

    Bernitsas, Michael M; Raghavan, Kamaldev

    2014-04-01

    Roughness is added to the surface of a bluff body in a relative motion with respect to a fluid. The amount, size, and distribution of roughness on the body surface is controlled passively or actively to modify the flow around the body and subsequently the Vortex Induced Forces and Motion (VIFM). The added roughness, when designed and implemented appropriately, affects in a predetermined way the boundary layer, the separation of the boundary layer, the level of turbulence, the wake, the drag and lift forces, and consequently the Vortex Induced Motion (VIM), and the fluid-structure interaction. The goal of surface roughness control is to decrease/suppress Vortex Induced Forces and Motion. Suppression is required when fluid-structure interaction becomes destructive as in VIM of flexible cylinders or rigid cylinders on elastic support, such as underwater pipelines, marine risers, tubes in heat exchangers, nuclear fuel rods, cooling towers, SPAR offshore platforms.

  5. Atomic-Level Measurements of Rough Surfaces | U.S. DOE Office of Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (SC) Atomic-Level Measurements of Rough Surfaces Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) Community Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301) 903-6594 E: Email Us More Information » 12.14.15 Atomic-Level Measurements of Rough

  6. Simulation of surface roughness during the formation of thermal spray coatings

    SciTech Connect (OSTI)

    Kanouff, M.P.

    1996-07-01

    The formation of a thermal spray coating was analyzed to identify methods to reduce the surface roughness of the coating. A new methodology was developed which uses a string of equally spaced node points to define the shape of the coating surface and to track the shape change as the thermal spray mass is deposited. This allows the calculation of arbitrary shapes for the coating surface which may be very complex. The model simulates the stochastic deposition of a large number of thermal spray droplets, where experimental data is used for the mass flux distribution on the target surface. This data shows that when the thermal spray mass impinges on the target surface, a large fraction of it (over-spray) splashes off the target and is re-deposited with a small spray angle, resulting in a large coating roughness. This analysis was used in a parameter study to identify methods for reducing the coating roughness. Effect of the shape of the profile for the pre-roughened substrate was found to be small. Decreasing the droplet size by a factor of 2 decreased the roughness by 13%. Increasing the spray angle for the over-spray by a factor of 2 decreased the roughness by 50%, and decreasing the amount of over- spray by a factor of 2 decreased the roughness by 51%.

  7. Ferroelectric PLZT thick films grown by poly(1-vinylpyrrolidone...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    PLZT thick films grown by poly(1-vinylpyrrolidone-co-vinyl acetate) (PVPVA)-modified sol-gel process Title Ferroelectric PLZT thick films grown by poly(1-vinylpyrrolidone-co-vi...

  8. Radiation phantom with humanoid shape and adjustable thickness

    DOE Patents [OSTI]

    Lehmann, Joerg; Levy, Joshua; Stern, Robin L.; Siantar, Christine Hartmann; Goldberg, Zelanna

    2006-12-19

    A radiation phantom comprising a body with a general humanoid shape and at least a portion having an adjustable thickness. In one embodiment, the portion with an adjustable thickness comprises at least one tissue-equivalent slice.

  9. Large-eddy simulations of surface roughness parameter sensitivity to canopy-structure characteristics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Maurer, K. D.; Bohrer, G.; Kenny, W. T.; Ivanov, V. Y.

    2015-04-30

    Surface roughness parameters, namely the roughness length and displacement height, are an integral input used to model surface fluxes. However, most models assume these parameters to be a fixed property of plant functional type and disregard the governing structural heterogeneity and dynamics. In this study, we use large-eddy simulations to explore, in silico, the effects of canopy-structure characteristics on surface roughness parameters. We performed a virtual experiment to test the sensitivity of resolved surface roughness to four axes of canopy structure: (1) leaf area index, (2) the vertical profile of leaf density, (3) canopy height, and (4) canopy gap fraction.more » We found roughness parameters to be highly variable, but uncovered positive relationships between displacement height and maximum canopy height, aerodynamic canopy height and maximum canopy height and leaf area index, and eddy-penetration depth and gap fraction. We also found negative relationships between aerodynamic canopy height and gap fraction, as well as between eddy-penetration depth and maximum canopy height and leaf area index. We generalized our model results into a virtual "biometric" parameterization that relates roughness length and displacement height to canopy height, leaf area index, and gap fraction. Using a decade of wind and canopy-structure observations in a site in Michigan, we tested the effectiveness of our model-driven biometric parameterization approach in predicting the friction velocity over heterogeneous and disturbed canopies. We compared the accuracy of these predictions with the friction-velocity predictions obtained from the common simple approximation related to canopy height, the values calculated with large-eddy simulations of the explicit canopy structure as measured by airborne and ground-based lidar, two other parameterization approaches that utilize varying canopy-structure inputs, and the annual and decadal means of the surface roughness parameters at the site from meteorological observations. We found that the classical representation of constant roughness parameters (in space and time) as a fraction of canopy height performed relatively well. Nonetheless, of the approaches we tested, most of the empirical approaches that incorporate seasonal and interannual variation of roughness length and displacement height as a function of the dynamics of canopy structure produced more precise and less biased estimates for friction velocity than models with temporally invariable parameters.« less

  10. Variable thickness double-refracting plate

    DOE Patents [OSTI]

    Hadeishi, Tetsuo

    1976-01-01

    This invention provides an A.C., cyclic, current-controlled, phase retardation plate that uses a magnetic clamp to produce stress birefringence. It was developed for an Isotope-Zeeman Atomic Absorption Spectrometer that uses polarization modulation to effect automatic background correction in atomic absorption trace-element measurements. To this end, the phase retardation plate of the invention is a variable thickness, photoelastic, double-refracting plate that is alternately stressed and released by the magnetic clamp selectively to modulate specific components selected from the group consisting of circularly and plane polarized Zeeman components that are produced in a dc magnetic field so that they correspond respectively to Zeeman reference and transmission-probe absorption components. The polarization modulation changes the phase of these polarized Zeeman components, designated as .sigma. reference and .pi. absorption components, so that every half cycle the components change from a transmission mode to a mode in which the .pi. component is blocked and the .sigma. components are transmitted. Thus, the Zeeman absorption component, which corresponds in amplitude to the amount of the trace element to be measured in a sample, is alternately transmitted and blocked by a linear polarizer, while the circularly polarized reference components are continuously transmitted thereby. The result is a sinusoidally varying output light amplitude whose average corresponds to the amount of the trace element present in the sample.

  11. Cladding Attachment Over Thick Exterior Insulating Sheathing

    SciTech Connect (OSTI)

    Baker, P.; Eng, P.; Lepage, R.

    2014-01-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1.What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2.Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3.What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  12. Cladding Attachment Over Thick Exterior Insulating Sheathing

    SciTech Connect (OSTI)

    Baker, P.; Eng, P.; Lepage, R.

    2014-01-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1. What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2. Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3. What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  13. Ultrasonic thickness measuring and imaging system and method

    DOE Patents [OSTI]

    Bylenok, Paul J.; Patmos, William M.; Wagner, Thomas A.; Martin, Francis H.

    1992-08-04

    An ultrasonic thickness measuring and imaging system uses an ultrasonic fsed beam probe for measuring thickness of an object, such as a wall of a tube, a computer for controlling movement of the probe in a scanning pattern within the tube and processing an analog signal produced by the probe which is proportional to the tube wall thickness in the scanning pattern, and a line scan recorder for producing a record of the tube wall thicknesses measured by the probe in the scanning pattern. The probe is moved in the scanning pattern to sequentially scan circumferentially the interior tube wall at spaced apart adjacent axial locations. The computer processes the analog signal by converting it to a digital signal and then quantifies the digital signal into a multiplicity of thickness points with each falling in one of a plurality of thickness ranges corresponding to one of a plurality of shades of grey. From the multiplicity of quantified thickness points, a line scan recorder connected to the computer generates a pictorial map of tube wall thicknesses with each quantified thickness point thus being obtained from a minute area, e.g. 0.010 inch by 0.010 inch, of tube wall and representing one pixel of the pictorial map. In the pictorial map of tube wall thicknesses, the pixels represent different wall thicknesses having different shades of grey.

  14. Ultrasonic thickness measuring and imaging system and method

    DOE Patents [OSTI]

    Bylenok, Paul J.; Patmos, William M.; Wagner, Thomas A.; Martin, Francis H.

    1992-01-01

    An ultrasonic thickness measuring and imaging system uses an ultrasonic fsed beam probe for measuring thickness of an object, such as a wall of a tube, a computer for controlling movement of the probe in a scanning pattern within the tube and processing an analog signal produced by the probe which is proportional to the tube wall thickness in the scanning pattern, and a line scan recorder for producing a record of the tube wall thicknesses measured by the probe in the scanning pattern. The probe is moved in the scanning pattern to sequentially scan circumferentially the interior tube wall at spaced apart adjacent axial locations. The computer processes the analog signal by converting it to a digital signal and then quantifies the digital signal into a multiplicity of thickness points with each falling in one of a plurality of thickness ranges corresponding to one of a plurality of shades of grey. From the multiplicity of quantified thickness points, a line scan recorder connected to the computer generates a pictorial map of tube wall thicknesses with each quantified thickness point thus being obtained from a minute area, e.g. 0.010 inch by 0.010 inch, of tube wall and representing one pixel of the pictorial map. In the pictorial map of tube wall thicknesses, the pixels represent different wall thicknesses having different shades of grey.

  15. Rough surface electrical contact resistance considering scale dependent properties and quantum effects

    SciTech Connect (OSTI)

    Jackson, Robert L.; Crandall, Erika R.; Bozack, Michael J.

    2015-05-21

    The objective of this work is to evaluate the effect of scale dependent mechanical and electrical properties on electrical contact resistance (ECR) between rough surfaces. This work attempts to build on existing ECR models that neglect potentially important quantum- and size-dependent contact and electrical conduction mechanisms present due to the asperity sizes on typical surfaces. The electrical conductance at small scales can quantize or show a stepping trend as the contact area is varied in the range of the free electron Fermi wavelength squared. This work then evaluates if these effects remain important for the interface between rough surfaces, which may include many small scale contacts of varying sizes. The results suggest that these effects may be significant in some cases, while insignificant for others. It depends on the load and the multiscale structure of the surface roughness.

  16. Effect of surface roughness and polymeric additive on nucleate pool boiling at subatmospheric pressures

    SciTech Connect (OSTI)

    Tewari, P.K.; Verma, R.K.; Ramani, M.P.S.; Mahajan, S.P.

    1986-09-01

    This investigation pertains to boiling heat transfer from a submerged flat surface at subatmospheric and atmospheric pressures in the presence of hydroxy ethyl cellulose (HEC) as a polymeric additive in small doses. Boiling was carried out in presence of the additive on smooth and rough aluminium surfaces having effective cavity size within the range as predicted by Hsu model and the pressure was kept in the range of 8 - 100 KN/sq.m (abs). Effects of surface roughness, saturation pressure and polymer concentration on boiling heat transfer were studied and the results were compared with Rohsenow's correlation.

  17. Effects of Volcanism, Crustal Thickness, and Large Scale Faulting...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Effects of Volcanism, Crustal Thickness, and Large Scale Faulting on the Development and Evolution of Geothermal Systems: Collaborative Project in Chile Effects of Volcanism, ...

  18. Variable Crustal Thickness In The Western Great Basin- A Compilation...

    Open Energy Info (EERE)

    et al., 2004). In addition, we have created contoured crustal thickness maps based on literature cited from the comprehensive Braile et al. (1989) study. These maps provide a...

  19. Coating thickness and coverage effects on the forces between...

    Office of Scientific and Technical Information (OSTI)

    forces between silica nanoparticles in water. Citation Details In-Document Search Title: Coating thickness and coverage effects on the forces between silica nanoparticles in water. ...

  20. 3-dimensional control over lamella orientation and order in thick...

    Office of Scientific and Technical Information (OSTI)

    3-dimensional control over lamella orientation and order in thick block copolymer films Citation Details In-Document Search Title: 3-dimensional control over lamella ...

  1. Large eddy simulations of surface roughness parameter sensitivity to canopy-structure characteristics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Maurer, K. D.; Bohrer, G.; Ivanov, V. Y.

    2014-11-27

    Surface roughness parameters are at the core of every model representation of the coupling and interactions between land-surface and atmosphere, and are used in every model of surface fluxes. However, most models assume these parameters to be a fixed property of plant functional type and do not vary them in response to spatial or temporal changes to canopy structure. In part, this is due to the difficulty of reducing the complexity of canopy structure and its spatiotemporal dynamic and heterogeneity to less than a handful of parameters describing its effects of atmosphere–surface interactions. In this study we use large-eddy simulationsmore » to explore, in silico, the effects of canopy structure characteristics on surface roughness parameters. We performed a virtual experiment to test the sensitivity of resolved surface roughness to four axes of canopy structure: (1) leaf area index, (2) the vertical profile of leaf density, (3) canopy height, and (4) canopy gap fraction. We found roughness parameters to be highly variable, but were able to find positive relationships between displacement height and maximum canopy height, aerodynamic canopy height and maximum canopy height and leaf area index, and eddy-penetration depth and gap fraction. We also found negative relationships between aerodynamic canopy height and gap fraction, and between eddy-penetration depth and maximum canopy height and leaf area index. Using a decade of wind and canopy structure observations in a site in Michigan, we tested the effectiveness of our model-resolved parameters in predicting the frictional velocity over heterogeneous and disturbed canopies. We compared it with three other semi-empirical models and with a decade of meteorological observations. We found that parameterizations with fixed representations of roughness performed relatively well. Nonetheless, some empirical approaches that incorporate seasonal and inter-annual changes to the canopy structure performed even better than models with temporally fixed parameters.« less

  2. Electrochemical machining process for forming surface roughness elements on a gas turbine shroud

    DOE Patents [OSTI]

    Lee, Ching-Pang (Cincinnati, OH); Johnson, Robert Alan (Simpsonville, SC); Wei, Bin (Mechanicville, NY); Wang, Hsin-Pang (Rexford, NY)

    2002-01-01

    The back side recessed cooling surface of a shroud defining in part the hot gas path of a turbine is electrochemically machined to provide surface roughness elements and spaces therebetween to increase the heat transfer coefficient. To accomplish this, an electrode with insulating dielectric portions and non-insulating portions is disposed in opposition to the cooling surface. By passing an electrolyte between the cooling surface and electrode and applying an electrical current between the electrode and a shroud, roughness elements and spaces therebetween are formed in the cooling surface in opposition to the insulating and non-insulating portions of the electrode, hence increasing the surface area and heat transfer coefficient of the shroud.

  3. The Effect of Excimer Laser Treatment on the Surface Roughness and Fracture Strength of Alumina Substrates

    SciTech Connect (OSTI)

    Smoot, J.E.

    1998-05-13

    The microelectronics industry requires alumina substrates with exceptionally smooth surfaces and few surface defects to allow successful deposition of metallic films for reliable electronic performance. Irradiation by a 248-nm wavelength excimer laser beam (KrF) at a fluence of 125 mJ/mm{sup 2} and at various angles of incidence is shown to significantly reduce the surface roughness of alumina substrates. However, irradiation also creates a fine particulate deposit of alumina that only partially adheres to the substrate and impedes deposition of metal films. Annealing in air between 1350 C and 1450 C was found to remove the particles by sintering. As-received material showed surface roughness average (R{sub a}) mean values of 457 nm, which was reduced to 60 nm (mean) following irradiation and 71 nm (mean) following irradiation and annealing at 1350 C. Irradiation also produced a decrease in the number and severity of surface defects. The flexural strength and Weibull modulus were both increased by laser irradiation and thermal treatment. Flexural strength went from an as-received value of 450 MPa to 560 MPa following irradiation/sintering, measured at 10% probability of failure. The Weibull modulus was increased from the as-received value of about 9, to about 13 following irradiation/sintering. It was concluded that irradiation at an angle of incidence of 60{degree} from perpendicular was most effective in producing a low surface roughness.

  4. Alternatives to lumber and plywood in home construction

    SciTech Connect (OSTI)

    Lund, E.

    1993-04-01

    The diminished supply and unstable price of lumber is compelling designers, builders, and developers to explore alternative materials for residential construction. The report discusses several commercially available alternative materials or building systems that may be used in framing and sheathing, including: engineered wood products; laminated fiberboard that can be used for sheathing walls; light-gauge structural steel components for floors, walls and roof systems; foam core structure sandwich panels for walls and roofs; and a variety of concrete and concrete block systems, many of which include insulation material.

  5. Control for monitoring thickness of high temperature refractory

    DOE Patents [OSTI]

    Caines, M.J.

    1982-11-23

    This invention teaches an improved monitoring device for detecting the changes in thickness of high-temperature refractory, the device consists of a probe having at least two electrically conductive generally parallel elements separated by a dielectric material. The probe is implanted or embedded directly in the refractory and is elongated to extend in line with the refractory thickness to be measured. Electrical inputs to the conductive elements provide that either or both the electrical conductance or capacitance can be found, so that charges over lapsed time periods can be compared in order to detect changes in the thickness of the refractory.

  6. Simultaneous orientation and thickness mapping in transmission electron microscopy

    SciTech Connect (OSTI)

    Tyutyunnikov, Dmitry; Özdöl, V. Burak; Koch, Christoph T.

    2014-12-04

    In this paper we introduce an approach for simultaneous thickness and orientation mapping of crystalline samples by means of transmission electron microscopy. We show that local thickness and orientation values can be extracted from experimental dark-field (DF) image data acquired at different specimen tilts. The method has been implemented to automatically acquire the necessary data and then map thickness and crystal orientation for a given region of interest. We have applied this technique to a specimen prepared from a commercial semiconductor device, containing multiple 22 nm technology transistor structures. The performance and limitations of our method are discussed and compared to those of other techniques available.

  7. Apparatus and method for measuring the thickness of a coating

    DOE Patents [OSTI]

    Carlson, Nancy M.; Johnson, John A.; Tow, David M.; Walter, John B

    2002-01-01

    An apparatus and method for measuring the thickness of a coating adhered to a substrate. An electromagnetic acoustic transducer is used to induce surface waves into the coating. The surface waves have a selected frequency and a fixed wavelength. Interpolation is used to determine the frequency of surface waves that propagate through the coating with the least attenuation. The phase velocity of the surface waves having this frequency is then calculated. The phase velocity is compared to known phase velocity/thickness tables to determine the thickness of the coating.

  8. A Simple Empirical Equation to Calculate Cloud Optical Thickness...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and high values of this quantity. With the above evidence in mind, we conclude that the empirical method described here is a useful tool for estimating cloud optical thickness at...

  9. Nanoscale selective area growth of thick, dense, uniform, In...

    Office of Scientific and Technical Information (OSTI)

    Title: Nanoscale selective area growth of thick, dense, uniform, In-rich, InGaN nanostructure arrays on GaNsapphire template Authors: Sundaram, S. 1 ; Puybaret, R. 2 ; El ...

  10. Extended, Continuous Pt Nanostructures in Thick, Dispersed Electrodes |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Extended, Continuous Pt Nanostructures in Thick, Dispersed Electrodes Extended, Continuous Pt Nanostructures in Thick, Dispersed Electrodes Presented at the Department of Energy Fuel Cell Projects Kickoff Meeting, September 1 - October 1, 2009 PDF icon pivovar_nrel_kickoff.pdf More Documents & Publications DOE's Fuel Cell Catalyst R&D Activities Fuel Cell Projects Kickoff Meeting PEMFC R&D at the DOE Fuel Cell Technologies Program

  11. Model-Independent Characterization of Charge Diffusion in Thick Fully

    Office of Scientific and Technical Information (OSTI)

    Depleted CCDs (Journal Article) | SciTech Connect Model-Independent Characterization of Charge Diffusion in Thick Fully Depleted CCDs Citation Details In-Document Search Title: Model-Independent Characterization of Charge Diffusion in Thick Fully Depleted CCDs We present a new method to measure charge diffusion in charge-coupled devices (CCDs). The method is based on a statistical characterization of the shapes of charge clouds produced by low-energy X-rays using known properties of the

  12. Axisymmetric Tandem Mirror Magnetic Fusion Energy Power Plant with Thick

    Office of Scientific and Technical Information (OSTI)

    Liquid-Walls (Conference) | SciTech Connect Conference: Axisymmetric Tandem Mirror Magnetic Fusion Energy Power Plant with Thick Liquid-Walls Citation Details In-Document Search Title: Axisymmetric Tandem Mirror Magnetic Fusion Energy Power Plant with Thick Liquid-Walls A fusion power plant is described that utilizes a new version of the tandem mirror device including spinning liquid walls. The magnetic configuration is evaluated with an axisymmetric equilibrium code predicting an average

  13. Coating thickness and coverage effects on the forces between silica

    Office of Scientific and Technical Information (OSTI)

    nanoparticles in water. (Journal Article) | SciTech Connect Coating thickness and coverage effects on the forces between silica nanoparticles in water. Citation Details In-Document Search Title: Coating thickness and coverage effects on the forces between silica nanoparticles in water. Abstract not provided. Authors: Salerno, Kenneth Michael ; Lane, J. Matthew ; Grest, Gary S. ; Ismail, Ahmed E. Publication Date: 2014-01-01 OSTI Identifier: 1140719 Report Number(s): SAND2014-0781J Journal

  14. Microfluidic devices with thick-film electrochemical detection

    DOE Patents [OSTI]

    Wang, Joseph; Tian, Baomin; Sahlin, Eskil

    2005-04-12

    An apparatus for conducting a microfluidic process and analysis, including at least one elongated microfluidic channel, fluidic transport means for transport of fluids through the microfluidic channel, and at least one thick-film electrode in fluidic connection with the outlet end of the microfluidic channel. The present invention includes an integrated on-chip combination reaction, separation and thick-film electrochemical detection microsystem, for use in detection of a wide range of analytes, and methods for the use thereof.

  15. Effects of roughness and temperature on low-energy hydrogen positive and negative ion reflection from silicon and carbon surfaces

    SciTech Connect (OSTI)

    Tanaka, N.; Kato, S.; Miyamoto, T.; Wada, M.; Nishiura, M.; Tsumori, K.; Matsumoto, Y.; Kenmotsu, T.; Okamoto, A.; Kitajima, S.; Sasao, M.; Yamaoka, H.

    2014-02-15

    Angle-resolved energy distribution functions of positive and negative hydrogen ions produced from a rough-finished Si surface under 1 keV proton irradiation have been measured. The corresponding distribution from a crystalline surface and a carbon surface are also measured for comparison. Intensities of positive and negative ions from the rough-finished Si are substantially smaller than those from crystalline Si. The angular distributions of these species are broader for rough surface than the crystalline surface. No significant temperature dependence for positive and negative ion intensities is observed for all samples in the temperature range from 300 to 400 K.

  16. Method and system for producing sputtered thin films with sub-angstrom thickness uniformity or custom thickness gradients

    DOE Patents [OSTI]

    Folta, James A.; Montcalm, Claude; Walton, Christopher

    2003-01-01

    A method and system for producing a thin film with highly uniform (or highly accurate custom graded) thickness on a flat or graded substrate (such as concave or convex optics), by sweeping the substrate across a vapor deposition source with controlled (and generally, time-varying) velocity. In preferred embodiments, the method includes the steps of measuring the source flux distribution (using a test piece that is held stationary while exposed to the source), calculating a set of predicted film thickness profiles, each film thickness profile assuming the measured flux distribution and a different one of a set of sweep velocity modulation recipes, and determining from the predicted film thickness profiles a sweep velocity modulation recipe which is adequate to achieve a predetermined thickness profile. Aspects of the invention include a practical method of accurately measuring source flux distribution, and a computer-implemented method employing a graphical user interface to facilitate convenient selection of an optimal or nearly optimal sweep velocity modulation recipe to achieve a desired thickness profile on a substrate. Preferably, the computer implements an algorithm in which many sweep velocity function parameters (for example, the speed at which each substrate spins about its center as it sweeps across the source) can be varied or set to zero.

  17. Effects of grit roughness and pitch oscillations on the S814 airfoil

    SciTech Connect (OSTI)

    Janiszewska, J.M.; Ramsay, R.R.; Hoffmann, M.J.; Gregorek, G.M. [Ohio State Univ., Columbus, OH (United States)

    1996-07-01

    Horizontal-axis wind turbine rotors experience unsteady aerodynamics when the rotor is yawed, when rotor blades pass through the support tower wake, and when the wind is gusting. An understanding of this unsteady behavior is necessary to assist in the design of new rotor airfoils. The rotors also experience performance degradation due to surface roughness. These surface irregularities are due to the accumulation of insect debris, ice, and/or the aging process. Wind tunnel studies that examine both the steady and unsteady behavior of airfoils can help define pertinent flow phenomena, and the resultant data can also be used to validate analytical computer codes. An S814 airfoil model was tested in The Ohio State University Aeronautical and Astronautical Research Laboratory (OSU/AARL) 3 X 5 subsonic wind tunnel (3 X 5) under steady flow with both stationary model conditions and pitch oscillations. To study the extent of performance loss due to surface roughness, a leading edge grit roughness pattern (LEGR) was used to simulate leading edge contamination. After baseline cases were completed, the LEGR was applied for both steady state and model pitch oscillation cases. The Reynolds numbers for steady state conditions were 0.75, 1, 1.25 and 1.5 million, while the angle of attack ranged from -20{degrees} to +40{degrees}. While the model underwent pitch oscillations, data were acquired at Reynolds numbers of 0.75, 1, 1.25, and 1.5 million, at frequencies of 0.6, 1.2, and 1.8 Hz. Two sine wave forcing functions {+-}5.5{degrees} and {+-}10{degrees}, were used; at mean angles of attack of 8{degrees}, 14{degrees}, and 20{degrees}. For purposes herein, any reference to unsteady conditions means the model was in pitch oscillation.

  18. Crustal-thickness variations in the central Andes

    SciTech Connect (OSTI)

    Beck, S.L.; Myers, S.C.; Wallace, T.C.; Zandt, G.; Silver, P.G.; Drake, L.

    1996-05-01

    We estimated the crustal thickness along an east-west transect across the Andes at lat 20{degree}S and along a north-south transect along the eastern edge of the Altiplano from data recorded on two arrays of portable broadband seismic stations (BANJO and SEDA). We found crustal-thickness variations of nearly 40 km across the Andes. Maximum crustal thicknesses of 70-74 km under the Western Cordillera and the Eastern Cordillera thin to 32-38 km 200 km east of the Andes in the Chaco Plain. The central Altiplano at 20{degree}S has crustal thicknesses of 60 to 65 km. The crust also appears to thicken from north (16{degree}S, 55-60 km) to south (20{degree}S, 70-74 km) along the Eastern Cordillera. The Subandean zone crust has intermediate thicknesses of 43 to 47 km. Crustal-thickness predictions for the Andes based on Airy-type isostatic behavior show remarkable overall correlation with observed crustal thickness in the regions of high elevation. In contrast, at the boundary between the Eastern Cordillera and the Subandean zone and in the Chaco Plain, the crust is thinner than predicted, suggesting that the crust in these regions is supported in part by the flexural rigidity of a strong lithosphere. With additional constraints, we conclude that the observation of Airy-type isostasy is consistent with thickening associated with compressional shortening of a weak lithosphere squeezed between the stronger lithosphere of the subducting Nazca plate and the cratonic lithosphere of the Brazilian craton. 26 refs., 4 figs.

  19. EFFECTS OF GRAPHITE SURFACE ROUGHNESS ON BYPASS FLOW COMPUTATIONS FOR AN HTGR

    SciTech Connect (OSTI)

    Rich Johnson; Yu-Hsin Tung; Hiroyuki Sato

    2011-07-01

    Bypass flow in a prismatic high temperature gas reactor (HTGR) occurs between graphite blocks as they sit side by side in the core. Bypass flow is not intentionally designed to occur in the reactor, but is present because of tolerances in manufacture, imperfect installation and expansion and shrinkage of the blocks from heating and irradiation. It is desired to increase the knowledge of the effects of such flow, which has been estimated to be as much as 20% of the total helium coolant flow. Computational fluid dynamic (CFD) simulations can provide estimates of the scale and impacts of bypass flow. Previous CFD calculations have examined the effects of bypass gap width, level and distribution of heat generation and effects of shrinkage. The present contribution examines the effects of graphite surface roughness on the bypass flow for different relative roughness factors on three gap widths. Such calculations should be validated using specific bypass flow measurements. While such experiments are currently underway for the specific reference prismatic HTGR design for the next generation nuclear plant (NGNP) program of the U. S. Dept. of Energy, the data are not yet available. To enhance confidence in the present calculations, wall shear stress and heat transfer results for several turbulence models and their associated wall treatments are first compared for flow in a single tube that is representative of a coolant channel in the prismatic HTGR core. The results are compared to published correlations for wall shear stress and Nusselt number in turbulent pipe flow. Turbulence models that perform well are then used to make bypass flow calculations in a symmetric onetwelfth sector of a prismatic block that includes bypass flow. The comparison of shear stress and Nusselt number results with published correlations constitutes a partial validation of the CFD model. Calculations are also compared to ones made previously using a different CFD code. Results indicate that increasing surface roughness increases the maximum fuel and helium temperatures as do increases in gap width. However, maximum coolant temperature variation due to increased gap width is not changed by surface roughness.

  20. Y-12's rough roads smoothed over with 23,000 tons of recycled asphalt |

    National Nuclear Security Administration (NNSA)

    National Nuclear Security Administration Home / Blog Y-12's rough roads smoothed over with 23,000 tons of recycled asphalt Tuesday, December 29, 2015 - 12:00am NNSA Blog Some 23,000 tons of asphalt removed during this summer's UPF site work have been put to use throughout the site. Potholes and gravel roads are now "paved" with the recycled asphalt that has been ground into a material called base course. Unlike gravel, the material tends to rebind into a solid form as it is packed

  1. Single-layer MoS{sub 2} roughness and sliding friction quenching by interaction with atomically flat substrates

    SciTech Connect (OSTI)

    Quereda, J.; Castellanos-Gomez, A.; Agrat, N.; Rubio-Bollinger, G.

    2014-08-04

    We experimentally study the surface roughness and the lateral friction force in single-layer MoS{sub 2} crystals deposited on different substrates: SiO{sub 2}, mica, and hexagonal boron nitride (h-BN). Roughness and sliding friction measurements are performed by atomic force microscopy. We find a strong dependence of the MoS{sub 2} roughness on the underlying substrate material, being h-BN the substrate which better preserves the flatness of the MoS{sub 2} crystal. The lateral friction also lowers as the roughness decreases, and attains its lowest value for MoS{sub 2} flakes on h-BN substrates. However, it is still higher than for the surface of a bulk MoS{sub 2} crystal, which we attribute to the deformation of the flake due to competing tip-to-flake and flake-to-substrate interactions.

  2. Thin dielectric film thickness determination by advanced transmission electron microscopy

    SciTech Connect (OSTI)

    Diebold, A.C.; Foran, B.; Kisielowski, C.; Muller, D.; Pennycook, S.; Principe, E.; Stemmer, S.

    2003-09-01

    High Resolution Transmission Electron Microscopy (HR-TEM) has been used as the ultimate method of thickness measurement for thin films. The appearance of phase contrast interference patterns in HR-TEM images has long been confused as the appearance of a crystal lattice by non-specialists. Relatively easy to interpret crystal lattice images are now directly observed with the introduction of annular dark field detectors for scanning TEM (STEM). With the recent development of reliable lattice image processing software that creates crystal structure images from phase contrast data, HR-TEM can also provide crystal lattice images. The resolution of both methods was steadily improved reaching now into the sub Angstrom region. Improvements in electron lens and image analysis software are increasing the spatial resolution of both methods. Optimum resolution for STEM requires that the probe beam be highly localized. In STEM, beam localization is enhanced by selection of the correct aperture. When STEM measurement is done using a highly localized probe beam, HR-TEM and STEM measurement of the thickness of silicon oxynitride films agree within experimental error. In this paper, the optimum conditions for HR-TEM and STEM measurement are discussed along with a method for repeatable film thickness determination. The impact of sample thickness is also discussed. The key result in this paper is the proposal of a reproducible method for film thickness determination.

  3. Simultaneous orientation and thickness mapping in transmission electron microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tyutyunnikov, Dmitry; Özdöl, V. Burak; Koch, Christoph T.

    2014-12-04

    In this paper we introduce an approach for simultaneous thickness and orientation mapping of crystalline samples by means of transmission electron microscopy. We show that local thickness and orientation values can be extracted from experimental dark-field (DF) image data acquired at different specimen tilts. The method has been implemented to automatically acquire the necessary data and then map thickness and crystal orientation for a given region of interest. We have applied this technique to a specimen prepared from a commercial semiconductor device, containing multiple 22 nm technology transistor structures. The performance and limitations of our method are discussed and comparedmore » to those of other techniques available.« less

  4. Method and apparatus for thickness measurement using microwaves

    DOE Patents [OSTI]

    Woskov, Paul [Bedford, MA; Lamar, David A. [West Richland, WA

    2001-01-01

    The method for measuring the thickness of a material which transmits a detectable amount of microwave radiation includes irradiating the material with coherent microwave radiation tuned over a frequency range. Reflected microwave radiation is detected, the reflected radiation having maxima and minima over the frequency range as a result of coherent interference of microwaves reflected from reflecting surfaces of the material. The thickness of the material is determined from the period of the maxima and minima along with knowledge of the index of refraction of the material.

  5. Quantum rings of non-uniform thickness in magnetic field

    SciTech Connect (OSTI)

    Rodrguez-Prada, F. A.; Garca, L. F.; Mikhailov, I. D.

    2014-05-15

    We consider a model of crater-shaped quantum dot in form of a thin layer whose thickness linearly increases with the distance from the axis. We show that one-particle wave equation for the electron confined in such structure can be completely separated in the adiabatic limit when the quantum dot thickness is much smaller than its lateral dimension. Analytical solutions found for this model has been used as base functions for analysing the effect of non-homogeneity on the electronic spectrum in the framework of the exact diagonalization method.

  6. Pump-Intensity- and Shell-Thickness-Dependent Evolution of

    Office of Scientific and Technical Information (OSTI)

    Photoluminescence Blinking in Individual Core/Shell CdSe/CdS Nanocrystals (Journal Article) | SciTech Connect Journal Article: Pump-Intensity- and Shell-Thickness-Dependent Evolution of Photoluminescence Blinking in Individual Core/Shell CdSe/CdS Nanocrystals Citation Details In-Document Search Title: Pump-Intensity- and Shell-Thickness-Dependent Evolution of Photoluminescence Blinking in Individual Core/Shell CdSe/CdS Nanocrystals Authors: Malko, Anton V. ; Park, Young-Shin ; Sampat,

  7. Process for manufacture of thick film hydrogen sensors

    DOE Patents [OSTI]

    Perdieu, Louisa H.

    2000-09-09

    A thick film process for producing hydrogen sensors capable of sensing down to a one percent concentration of hydrogen in carrier gasses such as argon, nitrogen, and air. The sensor is also suitable to detect hydrogen gas while immersed in transformer oil. The sensor includes a palladium resistance network thick film printed on a substrate, a portion of which network is coated with a protective hydrogen barrier. The process utilizes a sequence of printing of the requisite materials on a non-conductive substrate with firing temperatures at each step which are less than or equal to the temperature at the previous step.

  8. Determination of the effective sample thickness via radiative capture

    SciTech Connect (OSTI)

    Hurst, A. M.; Summers, N. C.; Szentmiklosi, L.; Firestone, R. B.; Basunia, M. S.; Escher, J. E.; Sleaford, B. W.

    2015-09-14

    Our procedure for determining the effective thickness of non-uniform irregular-shaped samples via radiative capture is described. In this technique, partial ?-ray production cross sections of a compound nucleus produced in a neutron-capture reaction are measured using Prompt Gamma Activation Analysis and compared to their corresponding standardized absolute values. For the low-energy transitions, the measured cross sections are lower than their standard values due to significant photoelectric absorption of the ? rays within the bulk-sample volume itself. Using standard theoretical techniques, the amount of ?-ray self absorption and neutron self shielding can then be calculated by iteratively varying the sample thickness until the observed cross sections converge with the known standards. The overall attenuation provides a measure of the effective sample thickness illuminated by the neutron beam. This procedure is illustrated through radiative neutron capture using powdered oxide samples comprising enriched 186W and 182W from which their tungsten-equivalent effective thicknesses are deduced to be 0.077(3) mm and 0.042(8) mm, respectively.

  9. Sensing roller for in-process thickness measurement

    DOE Patents [OSTI]

    Novak, J.L.

    1996-07-16

    An apparatus and method are disclosed for processing materials by sensing roller, in which the sensing roller has a plurality of conductive rings (electrodes) separated by rings of dielectric material. Sensing capacitances or impedances between the electrodes provides information on thicknesses of the materials being processed, location of wires therein, and other like characteristics of the materials. 6 figs.

  10. Sensing roller for in-process thickness measurement

    DOE Patents [OSTI]

    Novak, James L.

    1996-01-01

    An apparatus and method for processing materials by sensing roller, in which the sensing roller has a plurality of conductive rings (electrodes) separated by rings of dielectric material. Sensing capacitances or impedances between the electrodes provides information on thicknesses of the materials being processed, location of wires therein, and other like characteristics of the materials.

  11. Method and apparatus for conducting variable thickness vapor deposition

    DOE Patents [OSTI]

    Nesslage, G.V.

    1984-08-03

    A method of vapor depositing metal on a substrate in variable thickness comprises conducting the deposition continuously without interruption to avoid formation of grain boundaries. To achieve reduced deposition in specific regions a thin wire or ribbon blocking body is placed between source and substrate to partially block vapors from depositing in the region immediately below.

  12. A study of pitch oscillation and roughness on airfoils used for horizontal axis wind turbines

    SciTech Connect (OSTI)

    Gregorek, G.M.; Hoffmann, M.J.; Ramsay, R.R.; Janiszewska, J.M. [Ohio State Univ., Columbus, OH (United States)

    1995-12-01

    Under subcontract XF-1-11009-3 the Ohio State University Aeronautical and Astronautical Research Laboratory (OSU/AARL) with the National Renewable Energy Laboratory (NREL) developed an extensive database of empirical aerodynamic data. These data will assist in the development of analytical models and in the design of new airfoils for wind turbines. To accomplish the main objective, airfoil models were designed, built and wind tunnel tested with and without model leading edge grit roughness (LEGR). LEGR simulates surface irregularities due to the accumulation of insect debris, ice, and/or the aging process. This report is a summary of project project activity for Phase III, which encompasses the time period from September 17, 1 993 to September 6, 1 994.

  13. Organic photosensitive cells grown on rough electrode with nano-scale morphology control

    DOE Patents [OSTI]

    Yang, Fan; Forrest, Stephen R.

    2011-06-07

    An optoelectronic device and a method for fabricating the optoelectronic device includes a first electrode disposed on a substrate, an exposed surface of the first electrode having a root mean square roughness of at least 30 nm and a height variation of at least 200 nm, the first electrode being transparent. A conformal layer of a first organic semiconductor material is deposited onto the first electrode by organic vapor phase deposition, the first organic semiconductor material being a small molecule material. A layer of a second organic semiconductor material is deposited over the conformal layer. At least some of the layer of the second organic semiconductor material directly contacts the conformal layer. A second electrode is deposited over the layer of the second organic semiconductor material. The first organic semiconductor material is of a donor-type or an acceptor-type relative to the second organic semiconductor material, which is of the other material type.

  14. Light emitting diode with high aspect ratio submicron roughness for light extraction and methods of forming

    DOE Patents [OSTI]

    Li, Ting

    2013-08-13

    The surface morphology of an LED light emitting surface is changed by applying a reactive ion etch (RIE) process to the light emitting surface. High aspect ratio, submicron roughness is formed on the light emitting surface by transferring a thin film metal hard-mask having submicron patterns to the surface prior to applying a reactive ion etch process. The submicron patterns in the metal hard-mask can be formed using a low cost, commercially available nano-patterned template which is transferred to the surface with the mask. After subsequently binding the mask to the surface, the template is removed and the RIE process is applied for time duration sufficient to change the morphology of the surface. The modified surface contains non-symmetric, submicron structures having high aspect ratio which increase the efficiency of the device.

  15. Light emitting diode with high aspect ratio submicron roughness for light extraction and methods of forming

    DOE Patents [OSTI]

    Li, Ting

    2011-04-26

    The surface morphology of an LED light emitting surface is changed by applying a reactive ion etch (RIE) process to the light emitting surface. High aspect ratio, submicron roughness is formed on the light emitting surface by transferring a thin film metal hard-mask having submicron patterns to the surface prior to applying a reactive ion etch process. The submicron patterns in the metal hard-mask can be formed using a low cost, commercially available nano-patterned template which is transferred to the surface with the mask. After subsequently binding the mask to the surface, the template is removed and the RIE process is applied for time duration sufficient to change the morphology of the surface. The modified surface contains non-symmetric, submicron structures having high aspect ratio which increase the efficiency of the device.

  16. Thickness-insensitive selective surface paint. Status report

    SciTech Connect (OSTI)

    Moore, S.W.

    1985-03-01

    Testing and evaluation of passive Trombe/mass wall systems have identified the need for a selective absorber paint that can be applied to concrete, brick, or any storage or absorber surface that does not particularly lend itself to the application of a selective foil. Testing and modeling at Los Alamos have shown the large benefits that can result from the incorporation of selective surfaces into passive systems. The grouting and surface preparation required to prepare a storage wall for application of a selective foil have proven to be a problem area that can be highly labor intensive. Large thermal resistances between a selective foil and the storage mass can also severely degrade the selective absorber benefits. There is a great need for an inexpensive, good performing, paint-type selective coating that can be easily applied to solar absorber elements, that is, applied by merely spraying it on the rough, unprepared surface.

  17. Thick, low-stress films, and coated substrates formed therefrom

    DOE Patents [OSTI]

    Henager, Jr., Charles H.; Knoll, Robert W.

    1991-01-01

    Stress-induced deformation, and the damage resulting therefrom, increases with film thickness. The overcoming of excessive stress by the use of the film material of the present invention, permits the formation of thick films that are necessary for certain of the above described applications. The most likely use for the subject film materials, other than their specialized views as an optical film, is for microelectronic packaging of components on silicon substrates. In general, the subject Si-Al-O-N films have excellent adherence to the underlying substrate, a high degree of hardness and durability, and are excellent insulators. Prior art elevated temperature deposition processes cannot meet the microelectronic packaging temperature formation constraints. The process of the present invention is conducted under non-elevated temperature conditions, typically 500# C. or less.

  18. Method for making thick and/or thin film

    DOE Patents [OSTI]

    Pham, Ai Quoc; Glass, Robert S.

    2004-11-02

    A method to make thick or thin films a very low cost. The method is generally similar to the conventional tape casting techniques while being more flexible and versatile. The invention involves preparing a slip (solution) of desired material and including solvents such as ethanol and an appropriate dispersant to prevent agglomeration. The slip is then sprayed on a substrate to be coated using an atomizer which spreads the slip in a fine mist. Upon hitting the substrate, the solvent evaporates, leaving a green tape containing the powder and other additives, whereafter the tape may be punctured, cut, and heated for the desired application. The tape thickness can vary from about 1 .mu.m upward.

  19. Turbine blade having a constant thickness airfoil skin

    DOE Patents [OSTI]

    Marra, John J

    2012-10-23

    A turbine blade is provided for a gas turbine comprising: a support structure comprising a base defining a root of the blade and a framework extending radially outwardly from the base, and an outer skin coupled to the support structure framework. The skin has a generally constant thickness along substantially the entire radial extent thereof. The framework and the skin define an airfoil of the blade.

  20. Determination of the effective sample thickness via radiative capture

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hurst, A. M.; Summers, N. C.; Szentmiklosi, L.; Firestone, R. B.; Basunia, M. S.; Escher, J. E.; Sleaford, B. W.

    2015-09-14

    Our procedure for determining the effective thickness of non-uniform irregular-shaped samples via radiative capture is described. In this technique, partial γ-ray production cross sections of a compound nucleus produced in a neutron-capture reaction are measured using Prompt Gamma Activation Analysis and compared to their corresponding standardized absolute values. For the low-energy transitions, the measured cross sections are lower than their standard values due to significant photoelectric absorption of the γ rays within the bulk-sample volume itself. Using standard theoretical techniques, the amount of γ-ray self absorption and neutron self shielding can then be calculated by iteratively varying the sample thicknessmore » until the observed cross sections converge with the known standards. The overall attenuation provides a measure of the effective sample thickness illuminated by the neutron beam. This procedure is illustrated through radiative neutron capture using powdered oxide samples comprising enriched 186W and 182W from which their tungsten-equivalent effective thicknesses are deduced to be 0.077(3) mm and 0.042(8) mm, respectively.« less

  1. Hollow cylindrical plasma filament waveguide with discontinuous finite thickness cladding

    SciTech Connect (OSTI)

    Alshershby, Mostafa; Hao Zuoqiang; Lin Jingquan

    2013-01-15

    We have explored here a hollow cylindrical laser plasma multifilament waveguide with discontinuous finite thickness cladding, in which the separation between individual filaments is in the range of several millimeters and the waveguide cladding thickness is in the order of the microwave penetration depth. Such parameters give a closer representation of a realistic laser filament waveguide sustained by a long stable propagation of femtosecond (fs) laser pulses. We report how the waveguide losses depend on structural parameters like normalized plasma filament spacing, filament to filament distance or pitch, normal spatial frequency, and radius of the plasma filament. We found that for typical plasma parameters, the proposed waveguide can support guided modes of microwaves in extremely high frequency even with a cladding consisting of only one ring of plasma filaments. The loss of the microwave radiation is mainly caused by tunneling through the discontinuous finite cladding, i.e., confinement loss, and is weakly dependent on the plasma absorption. In addition, the analysis indicates that the propagation loss is fairly large compared with the loss of a plasma waveguide with a continuous infinite thickness cladding, while they are comparable when using a cladding contains more than one ring. Compared to free space propagation, this waveguide still presents a superior microwave transmission to some distance in the order of the filamentation length; thus, the laser plasma filaments waveguide may be a potential channel for transporting pulsed-modulated microwaves if ensuring a long and stable propagation of fs laser pulses.

  2. ARM: 10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1998-03-01

    10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  3. ARM: 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  4. ARM: 10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  5. ARM: 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  6. Image Formation by Incoherent and Coherent Transition Radiation from Flat and Rough Surfaces

    SciTech Connect (OSTI)

    Stupakov, Gennady; /SLAC

    2012-03-01

    In this paper we derive equations for the image formation of transverse profile of a relativistic beam obtained by means of optical transition radiation (OTR) from flat and rough metal surfaces. The motivation behind this study lies in the desire to suppress coherent transition radiation (COTR) observed in experiments at modern free electron lasers. The physical mechanism behind the problem of COTR is that the OTR is predominantly radiated at small angles of order of 1/{gamma} where {gamma} is the relativistic factor of the beam. This means that the transverse formation size of the image is of order of {bar {lambda}}{gamma} where {bar {lambda}} = {lambda}/2{pi} with {lambda} the radiation wavelength. For relativistic beams this can be comparable or even exceed the transverse size of the beam, which would mean that the image of the beam has very little to do with its transverse profile. It is fortuitous, however, that the incoherent image is formed by adding radiation energy of electrons and results in the transverse formation size being of order of {bar {lambda}}/{theta}{sub a}, with {theta}{sub a} is the aperture angle of the optical system. The COTR image, in contrast, is formed by adding electromagnetic field of electrons, and leads to the formation size {bar {lambda}}{gamma}. In situations when the COTR intensity exceeds that of OTR the COTR imaging makes the diagnostic incapable of measuring the beam profile.

  7. IDC Reengineering Phase 2 & 3 Rough Order of Magnitude (ROM) Cost Estimate Summary (Leveraged NDC Case).

    SciTech Connect (OSTI)

    Harris, James M.; Prescott, Ryan; Dawson, Jericah M.; Huelskamp, Robert M.

    2014-11-01

    Sandia National Laboratories has prepared a ROM cost estimate for budgetary planning for the IDC Reengineering Phase 2 & 3 effort, based on leveraging a fully funded, Sandia executed NDC Modernization project. This report provides the ROM cost estimate and describes the methodology, assumptions, and cost model details used to create the ROM cost estimate. ROM Cost Estimate Disclaimer Contained herein is a Rough Order of Magnitude (ROM) cost estimate that has been provided to enable initial planning for this proposed project. This ROM cost estimate is submitted to facilitate informal discussions in relation to this project and is NOT intended to commit Sandia National Laboratories (Sandia) or its resources. Furthermore, as a Federally Funded Research and Development Center (FFRDC), Sandia must be compliant with the Anti-Deficiency Act and operate on a full-cost recovery basis. Therefore, while Sandia, in conjunction with the Sponsor, will use best judgment to execute work and to address the highest risks and most important issues in order to effectively manage within cost constraints, this ROM estimate and any subsequent approved cost estimates are on a 'full-cost recovery' basis. Thus, work can neither commence nor continue unless adequate funding has been accepted and certified by DOE.

  8. Interpretation of recent seismic data from a frontier hydrocarbon province: western Rough Creek graben, southern Illinois and western Kentucky

    SciTech Connect (OSTI)

    Bertagne, A.J.; Pisasale, E.T.; Leising, T.C.

    1986-05-01

    The northern basement fault of the Rough Creek graben is seismically discernible and has surface expression in the Rough Creek fault zone. The southern basement fault is not clearly defined seismically, but can be inferred from shallow faulting and gravity data. This fault is roughly coincident with the Pennyrile fault zone. Extensional faults that formed the rift boundaries were the sites of late-stage compressional and extensional tectonics. Flower structures observed along the graben boundaries probably indicate post-Pennsylvanian wrench faulting. The basement within the graben plunges north-northwest, with the lowest point occurring south of the Rough Creek fault zone. Pre-Knox sediments thicken to approximately 12,000 in this area. The Knox Megagroup thickens toward the Mississippi Embayment, ranging from 4800 ft (southeastern graben area) to more than 7000 ft (west end of graben). Upper Ordovician to Devonian units also display westward thickening. The top of the Meramecian, New Albany, Maquoketa, and the base of the Knox generate continuous, high-amplitude seismic reflections due to large impedance contrasts between clastic and carbonate units. Shallow oil and gas production (Mississippian and Pennsylvanian) is present in this area. However, deep horizons (Knox, Lower Cambrian) remain relatively untested. Potential hydrocarbon traps in the pre-Knox sequence observed on seismic include fault blocks and updip pinch-outs.

  9. Quantifying the effect of anode surface roughness on diagnostic x-ray spectra using Monte Carlo simulation

    SciTech Connect (OSTI)

    Mehranian, A.; Ay, M. R.; Alam, N. Riyahi; Zaidi, H.

    2010-02-15

    Purpose: The accurate prediction of x-ray spectra under typical conditions encountered in clinical x-ray examination procedures and the assessment of factors influencing them has been a long-standing goal of the diagnostic radiology and medical physics communities. In this work, the influence of anode surface roughness on diagnostic x-ray spectra is evaluated using MCNP4C-based Monte Carlo simulations. Methods: An image-based modeling method was used to create realistic models from surface-cracked anodes. An in-house computer program was written to model the geometric pattern of cracks and irregularities from digital images of focal track surface in order to define the modeled anodes into MCNP input file. To consider average roughness and mean crack depth into the models, the surface of anodes was characterized by scanning electron microscopy and surface profilometry. It was found that the average roughness (R{sub a}) in the most aged tube studied is about 50 {mu}m. The correctness of MCNP4C in simulating diagnostic x-ray spectra was thoroughly verified by calling its Gaussian energy broadening card and comparing the simulated spectra with experimentally measured ones. The assessment of anode roughness involved the comparison of simulated spectra in deteriorated anodes with those simulated in perfectly plain anodes considered as reference. From these comparisons, the variations in output intensity, half value layer (HVL), heel effect, and patient dose were studied. Results: An intensity loss of 4.5% and 16.8% was predicted for anodes aged by 5 and 50 {mu}m deep cracks (50 kVp, 6 deg. target angle, and 2.5 mm Al total filtration). The variations in HVL were not significant as the spectra were not hardened by more than 2.5%; however, the trend for this variation was to increase with roughness. By deploying several point detector tallies along the anode-cathode direction and averaging exposure over them, it was found that for a 6 deg. anode, roughened by 50 {mu}m deep cracks, the reduction in exposure is 14.9% and 13.1% for 70 and 120 kVp tube voltages, respectively. For the evaluation of patient dose, entrance skin radiation dose was calculated for typical chest x-ray examinations. It was shown that as anode roughness increases, patient entrance skin dose decreases averagely by a factor of 15%. Conclusions: It was concluded that the anode surface roughness can have a non-negligible effect on output spectra in aged x-ray imaging tubes and its impact should be carefully considered in diagnostic x-ray imaging modalities.

  10. DYNAMIC DELAMINATION IN THROUGH-THICKNESS REINFORCED DCB SPECIMEN

    SciTech Connect (OSTI)

    N. SRIDHAR; ET AL

    2001-02-01

    Bridged crack models using beam theory formulation have proved to be effective in the modeling of quasistatic delamination crack growth in through thickness reinforced structures. In this paper, we model dynamic crack propagation in these structures with the beam theory formulation. Steady state crack propagation characteristics unique to the dynamic case are first identified. Dynamic crack propagation and the energetics of steady state dynamic crack growth for a Double Cantilever beam (DCB) configuration loaded with a flying wedge is examined next. We find that steady state crack growth is attainable for this loading configuration provided certain conditions are satisfied.

  11. Oil shale ash-layer thickness and char combustion kinetics

    SciTech Connect (OSTI)

    Aldis, D.F.; Singleton, M.F.; Watkins, B.E.; Thorsness, C.B.; Cena, R.J.

    1992-04-15

    A Hot-Recycled-Solids (HRS) oil shale retort is being studied at Lawrence Livermore National Laboratory. In the HRS process, raw shale is heated by mixing it with burnt retorted shale. Retorted shale is oil shale which has been heated in an oxygen deficient atmosphere to pyrolyze organic carbon, as kerogen into oil, gas, and a nonvolatile carbon rich residue, char. In the HRS retort process, the char in the spent shale is subsequently exposed to an oxygen environment. Some of the char, starting on the outer surface of the shale particle, is burned, liberating heat. In the HRS retort, the endothermic pyrolysis step is supported by heat from the exothermic char combustion step. The rate of char combustion is controlled by three resistances; the resistance of oxygen mass transfer through the gas film surrounding the solid particle, resistance to mass transfer through a ash layer which forms on the outside of the solid particles as the char is oxidized and the resistance due to the intrinsic chemical reaction rate of char and oxygen. In order to estimate the rate of combustion of the char in a typical oil shale particle, each of these resistances must be accurately estimated. We begin by modeling the influence of ash layer thickness on the over all combustion rate of oil shale char. We then present our experimental measurements of the ash layer thickness of oil shale which has been processed in the HRS retort.

  12. Lithospheric Thickness Modeled from Long Period Surface Wave Dispersion

    SciTech Connect (OSTI)

    Pasyanos, M E

    2008-05-15

    The behavior of surface waves at long periods is indicative of subcrustal velocity structure. Using recently published dispersion models, we invert surface wave group velocities for lithospheric structure, including lithospheric thickness, over much of the Eastern Hemisphere, encompassing Eurasia, Africa, and the Indian Ocean. Thicker lithosphere under Precambrian shields and platforms are clearly observed, not only under the large cratons (West Africa, Congo, Baltic, Russia, Siberia, India), but also under smaller blocks like the Tarim Basin and Yangtze craton. In contrast, it is found that remobilized Precambrian structures like the Saharan Shield and Sino-Korean Paraplatform do not have well-established lithospheric keels. The thinnest lithospheric thickness is found under oceanic and continental rifts, as well as along convergence zones. We compare our results to thermal models of continental lithosphere, lithospheric cooling models of oceanic lithosphere, lithosphere-asthenosphere boundary (LAB) estimates from S-wave receiver functions, and velocity variations of global tomography models. In addition to comparing results for the broad region, we examine in detail the regions of Central Africa, Siberia, and Tibet. While there are clear differences in the various estimates, overall the results are generally consistent. Inconsistencies between the estimates may be due to a variety of reasons including lateral and depth resolution differences and the comparison of what may be different lithospheric features.

  13. Mass gap for gravity localized on Weyl thick branes

    SciTech Connect (OSTI)

    Barbosa-Cendejas, N.; Santos, M. A. Reyes; Herrera-Aguilar, A.; Schubert, C.

    2008-06-15

    We consider thick brane configurations in a pure geometric Weyl integrable 5D space-time, a non-Riemannian generalization of Kaluza-Klein (KK) theory involving a geometric scalar field. Thus, the 5D theory describes gravity coupled to a self-interacting scalar field which gives rise to the structure of the thick branes. We continue the study of the properties of a previously found family of solutions which is smooth at the position of the brane but involves naked singularities in the fifth dimension. Analyzing their graviton spectrum, we find that a particularly interesting situation arises for a special case in which the 4D graviton is separated from the KK gravitons by a mass gap. The corresponding effective Schroedinger equation has a modified Poeschl-Teller potential and can be solved exactly. Apart from the massless 4D graviton, it contains one massive KK bound state, and the continuum spectrum of delocalized KK modes. We also discuss the mass hierarchy problem, and explicitly compute the corrections to Newton's law in the thin brane limit.

  14. Effects of grit roughness and pitch oscillations on the S809 airfoil

    SciTech Connect (OSTI)

    Ramsay, R.F.; Hoffman, M.J.; Gregorek, G.M. [Ohio State Univ., Columbus, OH (United States)

    1995-12-01

    An S809 airfoil model was tested in The Ohio State University Aeronautical and Astronautical Research Laboratory (OSU/AARL) 3{times}5 subsonic wind tunnel (3{times}5) under steady flow and stationary model conditions, and also with the model undergoing pitch oscillations. To study the possible extent of performance loss due to surface roughness, a standard grit pattern (LEGR) was developed to simulate leading edge contamination. After baseline cases were completed, the LEGR was applied for both steady state and model pitch oscillation cases. The Reynolds numbers for steady state conditions were 0.75, 1, 1.25, and 1.5 million, while the angle of attack ranged from {minus}20, to +40 {degrees}. With the model undergoing pitch oscillations, data were acquired at Reynolds numbers of 0.75, 1, 1.25, and 1.4 million, at frequencies of 0.6, 1.2, and 1.8 Hz. Two sine wave forcing functions were used; {plus_minus} 5.5{degrees} and {plus_minus} 10{degrees}, at mean angles of attack of 8{degrees}, 14{degrees}, and 20{degrees}. For purposes herein, any reference to unsteady conditions means the model was in pitch oscillation about the quarter chord. In general, the unsteady maximum lift coefficient was from 4% to 86% higher than the steady state maximum lift coefficient, and variation in the quarter chord pitching moment coefficient magnitude was from {minus}83% to 195% relative to steady state values at high angles of attack. These findings indicate the importance of considering the unsteady flow behavior occurring in wind turbine operation to obtain accurate load estimates.

  15. Fringe biasing: A variance reduction technique for optically thick meshes

    SciTech Connect (OSTI)

    Smedley-Stevenson, R. P.

    2013-07-01

    Fringe biasing is a stratified sampling scheme applicable to Monte Carlo thermal radiation transport codes. The thermal emission source in optically thick cells is partitioned into separate contributions from the cell interiors (where the likelihood of the particles escaping the cells is virtually zero) and the 'fringe' regions close to the cell boundaries. Thermal emission in the cell interiors can now be modelled with fewer particles, the remaining particles being concentrated in the fringes so that they are more likely to contribute to the energy exchange between cells. Unlike other techniques for improving the efficiency in optically thick regions (such as random walk and discrete diffusion treatments), fringe biasing has the benefit of simplicity, as the associated changes are restricted to the sourcing routines with the particle tracking routines being unaffected. This paper presents an analysis of the potential for variance reduction achieved from employing the fringe biasing technique. The aim of this analysis is to guide the implementation of this technique in Monte Carlo thermal radiation codes, specifically in order to aid the choice of the fringe width and the proportion of particles allocated to the fringe (which are interrelated) in multi-dimensional simulations, and to confirm that the significant levels of variance reduction achieved in simulations can be understood by studying the behaviour for simple test cases. The variance reduction properties are studied for a single cell in a slab geometry purely absorbing medium, investigating the accuracy of the scalar flux and current tallies on one of the interfaces with the surrounding medium. (authors)

  16. Composition and thickness of the southern Altiplano crust, Bolivia

    SciTech Connect (OSTI)

    Zandt, G.; Velasco, A.A. ); Beck, S.L. )

    1994-11-01

    Slant stacking of broadband seismograms recorded in the western United States for two 1993 intermediate-depth earthquakes that occurred near the Bolvia-Argentina-Chile borders reveals small but clear precursors to both the compressional (P) wave and shear (S) wave depth phases. We interpret and model these precursors as underside reflections from the thickened Andean Altiplano crust. We model the crustal structure of the Altiplano with a grid-search technique to match the timing and amplitudes of the depth phases and precursors in the waveforms of both the P wave and S wave. Our best-fit model has an average crust velocity of 5.9-6.0 km/s, a crustal V[sub p]/V[sub s] of 1.6, a crustal thickness of 75-80 km, and a high-velocity (V[sub p] = 8.4 km/s), high-V[sub p]/V[sub s] (1.9) mantle wedge. Assuming isotropy, the low V[sub p]/V[sub s] ratio of 1.6 for the crust corresponds to an anomalously low Poisson's ratio of 0.18. Such a low value, in conjunction with the low average V[sub p] estimate, is consistent only with a felsic composition and high upper-crustal temperatures. The finding of a thick felsic crust overlying a high-velocity mantle supports models of Altiplano uplift due predominantly to crustal shortening as opposed to mafic magmatic addition and is inconsistent with recent mantle delamination. 19 refs., 3 figs., 1 tab.

  17. Wall-slip of highly filled powder injection molding compounds: Effect of flow channel geometry and roughness

    SciTech Connect (OSTI)

    Hausnerova, Berenika; Sanetrnik, Daniel [Dept. of Production Engineering, Faculty of Technology, Tomas Bata University in Zlin, nm. T.G. Masaryka 5555, 760 01 Zln, Czech Republic and Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovc (Czech Republic); Paravanova, Gordana [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcrnou 3685, 760 01 Zln (Czech Republic)

    2014-05-15

    The paper deals with the rheological behavior of highly filled compounds proceeded via powder injection molding (PIM) and applied in many sectors of industry (automotive, medicine, electronic or military). Online rheometer equipped with slit dies varying in surface roughness and dimensions was applied to investigate the wall-slip as a rheological phenomenon, which can be considered as a parameter indicating the separation of compound components (polymer binder and metallic powder) during high shear rates when injection molded.

  18. Neutron skin thickness and neutron star equations of state: a strong relationship

    SciTech Connect (OSTI)

    Menezes, D. P.; Avancini, S. S.; Marinelli, J. R.; Watanabe de Moraes, M. M.; Providencia, C.

    2007-10-26

    A density dependent hadronic model and a common parametrization of the non-linear Walecka model are used to obtain the lead neutron skin thickness through its proton and neutron density profiles. The neutron skin thickness is known to reflect the equation of state properties. A direct correlation between the neutron skin thickness and the slope of the symmetry energy is found.

  19. Method and system using power modulation and velocity modulation producing sputtered thin films with sub-angstrom thickness uniformity or custom thickness gradients

    DOE Patents [OSTI]

    Montcalm, Claude; Folta, James Allen; Walton, Christopher Charles

    2003-12-23

    A method and system for determining a source flux modulation recipe for achieving a selected thickness profile of a film to be deposited (e.g., with highly uniform or highly accurate custom graded thickness) over a flat or curved substrate (such as concave or convex optics) by exposing the substrate to a vapor deposition source operated with time-varying flux distribution as a function of time. Preferably, the source is operated with time-varying power applied thereto during each sweep of the substrate to achieve the time-varying flux distribution as a function of time. Preferably, the method includes the steps of measuring the source flux distribution (using a test piece held stationary while exposed to the source with the source operated at each of a number of different applied power levels), calculating a set of predicted film thickness profiles, each film thickness profile assuming the measured flux distribution and a different one of a set of source flux modulation recipes, and determining from the predicted film thickness profiles a source flux modulation recipe which is adequate to achieve a predetermined thickness profile. Aspects of the invention include a computer-implemented method employing a graphical user interface to facilitate convenient selection of an optimal or nearly optimal source flux modulation recipe to achieve a desired thickness profile on a substrate. The method enables precise modulation of the deposition flux to which a substrate is exposed to provide a desired coating thickness distribution.

  20. Thick-Restart Laczos Method for Symmetric Eigenvalue Problems

    Energy Science and Technology Software Center (OSTI)

    1999-01-01

    This software package implements the thick-restart Lanczos method. It can be used on either a single address space machine or distributed parallel machine. The user can choose to implement or use a matrix-vector multiplication routine in any form convenient. Most of the arithmetic computations in the software are done through calls to BLAS and LAPACK. The software is written in Fortran 90. Because Fortran 90 offers many utility functions such functions such as dynamic memorymore » management, timing functions, random number generator and so on, the program is easily portable to different machines without modifying the source code. It can also be easily accessed from other language such as C or C-+. Since the software is highly modularized, it is relatively easy to adopt it for different type of situations. For example if the eigenvalue problem may have some symmetry and only a portion of the physical domain is discretized, then the dot-product routine needs to be modified. In this software, this modification is limited to one subroutine. It also can be instructed to write checkpoint files so that it can be restarted at a later time.« less

  1. Assessment of Nuclear Fuels using Radiographic Thickness Measurement Method

    SciTech Connect (OSTI)

    Muhammad Abir; Fahima Islam; Hyoung Koo Lee; Daniel Wachs

    2014-11-01

    The Convert branch of the National Nuclear Security Administration (NNSA) Global Threat Reduction Initiative (GTRI) focuses on the development of high uranium density fuels for research and test reactors for nonproliferation. This fuel is aimed to convert low density high enriched uranium (HEU) based fuel to high density low enriched uranium (LEU) based fuel for high performance research reactors (HPRR). There are five U.S. reactors that fall under the HPRR category, including: the Massachusetts Institute of Technology Reactor (MITR), the National Bureau of Standards Reactor (NBSR), the Missouri University Research Reactor (UMRR), the Advanced Test Reactor (ATR), and the High Flux Isotope Reactor (HFIR). U-Mo alloy fuel phase in the form of either monolithic or dispersion foil type fuels, such as ATR Full-size In center flux trap Position (AFIP) and Reduced Enrichment for Research and Test Reactor (RERTR), are being designed for this purpose. The fabrication process1 of RERTR is susceptible to introducing a variety of fuel defects. A dependable quality control method is required during fabrication of RERTR miniplates to maintain the allowable design tolerances, therefore evaluating and analytically verifying the fabricated miniplates for maintaining quality standards as well as safety. The purpose of this work is to analyze the thickness of the fabricated RERTR-12 miniplates using non-destructive technique to meet the fuel plate specification for RERTR fuel to be used in the ATR.

  2. Rotary union for use with ultrasonic thickness measuring probe

    DOE Patents [OSTI]

    Nachbar, Henry D.

    1992-01-01

    A rotary union for rotatably supporting an ultrasonic probe operable to nondestructively measure the thickness of steam generator tubes to determine the amount of corrosion experienced by the tubes includes a stationary body having a bore therethrough and an outlet drain, and a fitting rotatably mounted within the upper end of the body. The fitting has a bore aligned with the bore of the body. An electrical cable positioned within a water supply tube in an annular arrangement passes through the bore of the body and the bore of the fitting. This annular arrangement, in turn, is positioned within a connector element which extends outwardly from the fitting bore and is connected to the ultrasonic probe. An elastomeric lower bushing seals the annular arrangement to the lower end of the rotary union body and an elastomeric upper bushing seals the connector element to the fitting to permit the connector element and the ultrasonic probe connected thereto to rotate with the fitting relative to the body. The lower and upper bushings permit water to be passed through the annular arrangement and into the ultrasonic probe and thereafter discharged between the annular arrangement and the connector element to the outlet drain of the rotary union body.

  3. Cladding Attachment Over Thick Exterior Insulating Sheathing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of wood-framed walls and mass masonry wall assemblies. The location of the insulation on the exterior of the structure has many direct benefits, including better effective R-value from reduced thermal bridging, better condensation resistance, reduced thermal stress on the structure, as well as other commonly associated improvements such as increased airtightness and improved water management. For thick layers of exterior insulation (more than 1.5 in.), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location. Although the approach has proven effective, there is significant resistance to its widespread implementation due to a lack of research and understanding of the mechanisms involved in the development of the vertical displacement resistance capacity. In addition, the long-term in-service performance of the system has been questioned due to potential creep effects of the assembly under the sustained dead load of the cladding and effects of varying environmental conditions. In addition, the current International Building Code (IBC) and International Residential Code (IRC) do not have a provision that specifically allows this assembly.

  4. Rotary union for use with ultrasonic thickness measuring probe

    DOE Patents [OSTI]

    Nachbar, H.D.

    1992-09-15

    A rotary union for rotatably supporting an ultrasonic probe operable to nondestructively measure the thickness of steam generator tubes to determine the amount of corrosion experienced by the tubes includes a stationary body having a bore therethrough and an outlet drain, and a fitting rotatably mounted within the upper end of the body. The fitting has a bore aligned with the bore of the body. An electrical cable positioned within a water supply tube in an annular arrangement passes through the bore of the body and the bore of the fitting. This annular arrangement, in turn, is positioned within a connector element which extends outwardly from the fitting bore and is connected to the ultrasonic probe. An elastomeric lower bushing seals the annular arrangement to the lower end of the rotary union body and an elastomeric upper bushing seals the connector element to the fitting to permit the connector element and the ultrasonic probe connected thereto to rotate with the fitting relative to the body. The lower and upper bushings permit water to be passed through the annular arrangement and into the ultrasonic probe and thereafter discharged between the annular arrangement and the connector element to the outlet drain of the rotary union body. 5 figs.

  5. On the improvement of photovoltaic action of ZnO/P3HT:PCBM by controlling roughness of window layer

    SciTech Connect (OSTI)

    Geethu, R. Menon, M. R. Rajesh Kartha, C. Sudha Vijayakumar, K. P.

    2014-04-24

    Polymer solar cells with configuration ITO/ZnO/P3HT:PCBM/Ag were fabricated using cost effective chemical spray pyrolysis and spin coating techniques. When surface of ZnO layer was modified with a second layer so as to increase the roughness, considerable improvement in cell parameters were observed. Optimum conditions for the required roughness were identified and changes in cell parameters with variation in surface roughness were studied. Major enhancements were observed in the open circuit voltage and in the cell efficiency.

  6. Surface smoothing effect of an amorphous thin film deposited by atomic layer deposition on a surface with nano-sized roughness

    SciTech Connect (OSTI)

    Lau, W. S. Wan, X.; Xu, Y.; Wong, H.; Zhang, J.; Luo, J. K.; Institute of Renewable Energy and Environment Technology, Bolton University, Deane Road, Bolton BL3 5 AB

    2014-02-15

    Previously, Lau (one of the authors) pointed out that the deposition of an amorphous thin film by atomic layer deposition (ALD) on a substrate with nano-sized roughness probably has a surface smoothing effect. In this letter, polycrystalline zinc oxide deposited by ALD onto a smooth substrate was used as a substrate with nano-sized roughness. Atomic force microscopy (AFM) and cross-sectional transmission electron microscopy (XTEM) were used to demonstrate that an amorphous aluminum oxide thin film deposited by ALD can reduce the surface roughness of a polycrystalline zinc oxide coated substrate.

  7. Thick Concrete Specimen Construction, Testing, and Preliminary Analysis

    SciTech Connect (OSTI)

    Clayton, Dwight A.; Hoegh, Kyle; Khazanovich, Lev

    2015-03-01

    The purpose of the U.S. Department of Energy Office of Nuclear Energy’s Light Water Reactor Sustainability (LWRS) Program is to develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the operating lifetimes of nuclear power plants (NPPs) beyond 60 years. Since many important safety structures in an NPP are constructed of concrete, inspection techniques must be developed and tested to evaluate the internal condition. In-service containment structures generally do not allow for the destructive measures necessary to validate the accuracy of these inspection techniques. This creates a need for comparative testing of the various nondestructive evaluation (NDE) measurement techniques on concrete specimens with known material properties, voids, internal microstructure flaws, and reinforcement locations. A preliminary report detailed some of the challenges associated with thick reinforced concrete sections and prioritized conceptual designs of specimens that could be fabricated to represent NPP concrete structures for using in NDE evaluation comparisons. This led to the construction of the concrete specimen presented in this report, which has sufficient reinforcement density and cross-sectional size to represent an NPP containment wall. Details on how a suitably thick concrete specimen was constructed are presented, including the construction materials, final nominal design schematic, as well as formwork and rigging required to safely meet the desired dimensions of the concrete structure. The report also details the type and methods of forming the concrete specimen as well as information on how the rebar and simulated defects were embedded. Details on how the resulting specimen was transported, safely anchored, and marked to allow access for systematic comparative NDE testing of defects in a representative NPP containment wall concrete specimen are also given. Data collection using the MIRA Ultrasonic NDE equipment and initial results are also presented along with a discussion of the preliminary findings. Comparative NDE of various defects in reinforced concrete specimens is a key component in identifying the most promising techniques and directing the research and development efforts needed to characterize concrete degradation in commercial NPPs. This requires access to the specimens for data collection using state-of-the-art technology. The construction of the specimen detailed in this report allows for an evaluation of how different NDE techniques may interact with the size and complexities of NPP concrete structures. These factors were taken into account when determining specimen size and features to ensure a realistic design. The lateral dimensions of the specimen were also chosen to mitigate unrealistic boundary effects that would not affect the results of field NPP concrete testing. Preliminary results show that, while the current methods are able to identify some of the deeper defects, improvements in data processing or hardware are necessary to be able to achieve the precision and reliability achieved in evaluating thinner and less heavily reinforced concrete structures.

  8. Thin-thick hydrogen target for nuclear physics

    SciTech Connect (OSTI)

    Gheller, J.-M.; Juster, F.-P.; Authelet, G.; Relland, J.

    2014-01-29

    In spectroscopic studies of unstable nuclei, hydrogen targets are of key importance. The CHyMENE Project aims to provide to the nuclear physics community a thin and pure solid windowless hydrogen or deuterium target. CHyMENE project must respond to this request for the production of solid Hydrogen. The solid hydrogen target is produced in a continuous flow (1 cm/s) by an extrusion technique (developed with the PELIN laboratory) in a vacuum chamber. The shape of the target is determined by the design of the nozzle at the extrusion process. For the purpose, the choice is a rectangular shape with a width of 10 mm and a thickness in the range of 30-50 microns necessary for the physics objectives. The cryostat is equipped with a GM Cryocooler with sufficient power for the solidification of the hydrogen in the lower portion of the extruder. In the higher part of the cryostat, the hydrogen gas is first liquefied and partially solidified. It is then compressed at 100 bars in the cooled extruder before expulsion of the film through the nozzle at the center of the reaction vacuum chamber. After the previous step, the solid hydrogen ribbon falls by gravity into a dedicated chamber where it sublimes and the gas is pumped and evacuated in a exhaust line. This paper deals with the design of the cryostat with its equipment, with the sizing of the thermal bridge (Aluminum and copper), with the results regarding the contact resistance as well as with the vacuum computations of the reaction and recovery hydrogen gas chambers.

  9. Effect of Ru thickness on spin pumping in Ru/Py bilayer

    SciTech Connect (OSTI)

    Behera, Nilamani; Singh, M. Sanjoy; Chaudhary, Sujeet; Pandya, Dinesh K. Muduli, P. K.

    2015-05-07

    We report the effect of Ru thickness (t{sub Ru}) on ferromagnetic resonance (FMR) line-width of Ru(t{sub Ru})/Py(23?nm) bilayer samples grown on Si(100)/SiO{sub 2} substrates at room temperature by magnetron sputtering. The FMR line-width is found to vary linearly with frequency for all thicknesses of Ru, indicating intrinsic origin of damping. For Ru thicknesses below 15?nm, Gilbert-damping parameter, ? is almost constant. We ascribe this behavior to spin back flow that is operative for Ru thicknesses lower than the spin diffusion length in Ru, ?{sub sd}. For thicknesses >15?nm (>?{sub sd}), the damping constant increases with Ru thickness, indicating spin pumping from Py into Ru.

  10. SU-E-T-319: The Effect of Slice Thickness On IMRT Planning

    SciTech Connect (OSTI)

    Srivastava, S; Das, I; Cheng, C

    2014-06-01

    Purpose: The accuracy of volume estimated of a treatment planning system is investigated in this study. In addition, the effect of slice thickness on IMRT planning is also studied. Methods: The accuracy in volume determination was investigated using a water phantom containing various objects with known volumes ranging from 1100cm{sup 3}. The phantom was scanned with different slice thickness (110 mm). The CT data sets were sent to Eclipse TPS for contour delineation and volume calculation. The effect of slice thickness on IMRT planning was studied using a commercial phantom containing four different shaped objects. The phantom was scanned with different slice thickness (15 mm). IMRT plans were generated for the different CT datasets to calculate TCP, homogeneity (HI) and conformity indices (CI). Results: The variability of volumes with CT slice thickness was significant especially for small volume structures. The minimum and maximum error in the volume estimation is in the range of ?2.3% to 92%. On the other hand, with increasing slice thickness, the PTV mean dose and TCP values decreases. Maximum variation of ?5% was observed in mean dose and ?2% in TCP with slice thickness change from 15 mm. The relative decrease in target volume receiving 95% of prescribed dose is ?5% slice thickness change from 15 mm. HI increases up to 163% and CI decreases by 4% between 15 mm slice thickness change, producing highly inhomogeneous and least conformal plan. Conclusion: Accuracy of volume estimation is dependent on CT slice thickness and the contouring algorithm in a TPS. During TPS commissioning and for all clinical protocols, evaluation of volume should be included to provide the limit of accuracy in DVH calculation. A smaller slice thickness provides superior dosimetry with improved TCP values. Thus, the smallest possible slice thickness should be used for IMRT planning.

  11. Bandgap Engineering of InP QDs Through Shell Thickness and Composition...

    Office of Scientific and Technical Information (OSTI)

    Bandgap Engineering of InP QDs Through Shell Thickness and Composition Citation Details ... Subject: 36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ...

  12. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2010-12-15

    10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  13. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  14. Riser Difference Evaluation from Ultrasonic Wall Thickness Inspection of Thirteen Double-Shell Tanks

    SciTech Connect (OSTI)

    Weier, Dennis R.; Pardini, Allan F.

    2010-03-15

    PNNL has performed an analysis of ultrasonic thickness measurements taken on Hanford's double-shell tanks (DSTs) approximately eight years apart. The analysis was performed to determine whether significant differences exist between ultrasonic thickness measurements made in two opposite risers in Hanford DSTs that have been examined twice.

  15. Density dependence of the symmetry energy from neutron skin thickness in finite nuclei

    SciTech Connect (OSTI)

    Vinas, X.; Centelles, M.; Roca-Maza, X.; Warda, M.

    2012-10-20

    The density dependence of the symmetry energy, characterized by the parameter L, is studied using information provided by the neutron skin thickness in finite nuclei. An estimate of L is obtained from experimental data of antiprotonic atoms. We also discuss the ability of parity violating electron scatering to obtain information about the neutron skin thickness in {sup 208}Pb.

  16. Enhancing through thickness thermal conductivity of ultra-thin composite laminates. Final report

    SciTech Connect (OSTI)

    Ramani, K.; Vaidyanathan, A.

    1994-12-31

    The materials used in electronic applications have specific requirements for stiffness, thermal conductivity, and electromagnetic shielding making the choice of materials used very important. Electronic components are very sensitive to heat, hence the heat dissipation or cooling of the various components is necessary to prevent failure. Thus, any material used in the electronic industry must have a high thermal conductivity in addition to a specified thermal expansion, stiffness and strength properties. The purpose of this project was to design and manufacture composite panels which would conduct heat from an electronic chip attached to the top surface to a cooling liquid flowing at its lower surface. To maximize the heat conducted from the chip to the cooling liquid, the composite must have a high through thickness thermal conductivity. Further, design restrictions on the thickness of the composite panel had to be taken into account. It was found that the presence of excess resin adversely affects the conductivity of a woven fabric composite due to which the through thickness conductivity of the 400 {micro}m thick panel was better than the 500 {micro}m thick panel. The through thickness conductivity of the panel with short fibers alone was better than that of the woven cloth panel. The finite element model developed for a priori prediction of the through thickness thermal conductivity of the composite panels is a very powerful tool that can save enormous prototyping times an associates coats.

  17. In situ measurement of low-Z material coating thickness on high Z substrate for tokamaks

    SciTech Connect (OSTI)

    Mueller, D. Roquemore, A. L.; Jaworski, M.; Skinner, C. H.; Miller, J.; Creely, A.; Raman, P.; Ruzic, D.

    2014-11-15

    Rutherford backscattering of energetic particles can be used to determine the thickness of a coating of a low-Z material over a heavier substrate. Simulations indicate that 5 MeV alpha particles from an {sup 241}Am source can be used to measure the thickness of a Li coating on Mo tiles between 0.5 and 15??m thick. Using a 0.1?mCi source, a thickness measurement can be accomplished in 2 h of counting. This technique could be used to measure any thin, low-Z material coating (up to 1?mg/cm{sup 2} thick) on a high-Z substrate, such as Be on W, B on Mo, or Li on Mo. By inserting a source and detector on a moveable probe, this technique could be used to provide an in situ measurement of the thickness of Li coating on NSTX-U Mo tiles. A test stand with an alpha source and an annular solid-state detector was used to investigate the measurable range of low-Z material thicknesses on Mo tiles.

  18. In-situ Measurement of Low-Z Material Coating Thickness on High Z Substrate

    Office of Scientific and Technical Information (OSTI)

    for Tokamaks (Conference) | SciTech Connect Conference: In-situ Measurement of Low-Z Material Coating Thickness on High Z Substrate for Tokamaks Citation Details In-Document Search Title: In-situ Measurement of Low-Z Material Coating Thickness on High Z Substrate for Tokamaks Rutherford backscattering (RBS) of energetic particles can be used to determine the thickness of a coating of a low-Z material over a heavier substrate. Simulations indicate that 5 MeV alpha particles from an Am source

  19. A JOINT MODEL OF X-RAY AND INFRARED BACKGROUNDS. II. COMPTON-THICK ACTIVE

    Office of Scientific and Technical Information (OSTI)

    GALACTIC NUCLEUS ABUNDANCE (Journal Article) | SciTech Connect X-RAY AND INFRARED BACKGROUNDS. II. COMPTON-THICK ACTIVE GALACTIC NUCLEUS ABUNDANCE Citation Details In-Document Search Title: A JOINT MODEL OF X-RAY AND INFRARED BACKGROUNDS. II. COMPTON-THICK ACTIVE GALACTIC NUCLEUS ABUNDANCE We estimate the abundance of Compton-thick (CT) active galactic nuclei (AGNs) based on our joint model of X-ray and infrared backgrounds. At L{sub rest2-10{sub keV}} > 10{sup 42} erg s{sup -1}, the CT

  20. ORIGIN OF CHEMICAL AND DYNAMICAL PROPERTIES OF THE GALACTIC THICK DISK

    SciTech Connect (OSTI)

    Bekki, Kenji [ICRAR, M468, University of Western Australia, Crawley, Western Australia, 6009 (Australia); Tsujimoto, Takuji [National Astronomical Observatory, Mitaka-shi, Tokyo 181-8588 (Japan)

    2011-09-01

    We adopt a scenario in which the Galactic thick disk was formed by minor merging between the first generation of the Galactic thin disk (FGTD) and a dwarf galaxy about {approx}9 Gyr ago and thereby investigate chemical and dynamical properties of the Galactic thick disk. In this scenario, the dynamical properties of the thick disk have long been influenced both by the mass growth of the second generation of the Galactic thin disk (i.e., the present thin disk) and by its non-axisymmetric structures. On the other hand, the early star formation history and chemical evolution of the thin disk was influenced by the remaining gas of the thick disk. Based on N-body simulations and chemical evolution models, we investigate the radial metallicity gradient, structural and kinematical properties, and detailed chemical abundance patterns of the thick disk. Our numerical simulations show that the ancient minor merger event can significantly flatten the original radial metallicity gradient of the FGTD, in particular, in the outer part, and also can be responsible for migration of inner metal-rich stars into the outer part (R > 10 kpc). The simulations show that the central region of the thick disk can develop a bar due to dynamical effects of a separate bar in the thin disk. Whether or not rotational velocities (V{sub {phi}}) can correlate with metallicities ([Fe/H]) for the simulated thick disks depends on the initial metallicity gradients of the FGTDs. The simulated orbital eccentricity distributions in the thick disk for models with higher mass ratios ({approx}0.2) and lower orbital eccentricities ({approx}0.5) of minor mergers are in good agreement with the corresponding observations. The simulated V{sub {phi}}-|z| relation of the thick disk in models with low orbital inclination angles of mergers are also in good agreement with the latest observational results. The vertical metallicity gradient of the simulated thick disk is rather flat or very weakly negative in the solar neighborhood. Our Galactic chemical evolution models show that if we choose two distinctive timescales for star formation in the thin and thick disks, then the models can explain both the observed metallicity distribution functions and correlations between [Mg/Fe] and [Fe/H] for the two disks in a self-consistent manner. We discuss how the early star formation history and chemical evolution of the Galactic thin disk can be influenced by the pre-existing thick disk.

  1. In situ measurement of low-Z material coating thickness on high...

    Office of Scientific and Technical Information (OSTI)

    an sup 241Am source can be used to measure the thickness of a Li coating on Mo tiles ... This technique could be used to measure any thin, low-Z material coating (up to 1 mg...

  2. Microsystems enabled photovoltaics 14.9% efficient 14μm thick...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Microsystems enabled photovoltaics: 14.9% efficient 14 mm thick crystalline silicon solar cell Jose L. Cruz-Campa a,b,n , Murat Okandan a , Paul J. Resnick a , Peggy Clews a , ...

  3. On-Line Measurement of Lubricant Film Thickness Using Ultrasonic Reflection Coefficients

    SciTech Connect (OSTI)

    Drinkwater, B.W.; Dwyer-Joyce, R.S.; Harper, P.

    2004-02-26

    The ultrasonic reflectivity of a lubricant layer between two solid bodies depends on the ultrasonic frequency, the acoustic properties of the liquid and solid, and the layer thickness. In this paper, ultrasonic reflectivity measurements are used as a method for determining the thickness of lubricating films in bearing systems. An ultrasonic transducer is positioned on the outside of a bearing shell such that the wave is focused on the lubricant film layer. For a particular lubricant film the reflected pulse is processed to give a reflection coefficient spectrum. The lubricant film thickness is then obtained from either the layer stiffness or the resonant frequency. The method has been validated using static fluid wedges and the elastohydrodynamic film formed between a ball sliding on a flat. Film thickness values in the range 50-500 nm were recorded which agreed well with theoretical film formation predictions.

  4. Coupled escape probability for an asymmetric spherical case: Modeling optically thick comets

    SciTech Connect (OSTI)

    Gersch, Alan M.; A'Hearn, Michael F.

    2014-05-20

    We have adapted Coupled Escape Probability, a new exact method of solving radiative transfer problems, for use in asymmetrical spherical situations. Our model is intended specifically for use in modeling optically thick cometary comae, although not limited to such use. This method enables the accurate modeling of comets' spectra even in the potentially optically thick regions nearest the nucleus, such as those seen in Deep Impact observations of 9P/Tempel 1 and EPOXI observations of 103P/Hartley 2.

  5. Bandgap Engineering of InP QDs Through Shell Thickness and Composition

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Bandgap Engineering of InP QDs Through Shell Thickness and Composition Citation Details In-Document Search Title: Bandgap Engineering of InP QDs Through Shell Thickness and Composition Fields as diverse as biological imaging and telecommunications utilize the unique photophysical and electronic properties of nanocrystal quantum dots (NQDs). The development of new NQD compositions promises material properties optimized for specific applications, while addressing

  6. Compression of 1-mm-thick M9763 cellular silicone foam under lateral

    Office of Scientific and Technical Information (OSTI)

    confinement (Technical Report) | SciTech Connect Compression of 1-mm-thick M9763 cellular silicone foam under lateral confinement Citation Details In-Document Search Title: Compression of 1-mm-thick M9763 cellular silicone foam under lateral confinement Abstract not provided. Authors: Small, W. [1] + Show Author Affiliations Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States) Publication Date: 2014-11-13 OSTI Identifier: 1183540 Report Number(s): LLNL-TR--667442 DOE

  7. 3-dimensional control over lamella orientation and order in thick block

    Office of Scientific and Technical Information (OSTI)

    copolymer films (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: 3-dimensional control over lamella orientation and order in thick block copolymer films Citation Details In-Document Search Title: 3-dimensional control over lamella orientation and order in thick block copolymer films Authors: Olszowka, Violetta ; Tsarkova, Larisa ; Böker, Alexander [1] + Show Author Affiliations Bayreuth Publication Date: 2016-04-06 OSTI Identifier: 1245839 Resource Type:

  8. Ferroelectric PLZT thick films grown by poly(1-vinylpyrrolidone-co-vinyl

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ferrin Moore, Senior Aviation Policy Officer - Bio Ferrin Moore, Senior Aviation Policy Officer - Bio PDF icon Ferrin_MoorePersonalProfile.pdf More Documents & Publications LopezPersonalProfile.pdf Patricia Hagerty, Aviation Program Analyst - Bio - FLIGHT - acetate) (PVP/VA)-modified sol-gel process | Argonne National Laboratory

    Ferroelectric PLZT thick films grown by poly(1-vinylpyrrolidone-co-vinyl acetate) (PVP/VA)-modified sol-gel process Title Ferroelectric PLZT thick films grown

  9. Review of the margins for ASME code fatigue design curve - effects of surface roughness and material variability.

    SciTech Connect (OSTI)

    Chopra, O. K.; Shack, W. J.; Energy Technology

    2003-10-03

    The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. The Code specifies fatigue design curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Existing fatigue strain-vs.-life ({var_epsilon}-N) data illustrate potentially significant effects of LWR coolant environments on the fatigue resistance of pressure vessel and piping steels. This report provides an overview of the existing fatigue {var_epsilon}-N data for carbon and low-alloy steels and wrought and cast austenitic SSs to define the effects of key material, loading, and environmental parameters on the fatigue lives of the steels. Experimental data are presented on the effects of surface roughness on the fatigue life of these steels in air and LWR environments. Statistical models are presented for estimating the fatigue {var_epsilon}-N curves as a function of the material, loading, and environmental parameters. Two methods for incorporating environmental effects into the ASME Code fatigue evaluations are discussed. Data available in the literature have been reviewed to evaluate the conservatism in the existing ASME Code fatigue evaluations. A critical review of the margins for ASME Code fatigue design curves is presented.

  10. Local changes of work function near rough features on Cu surfaces operated under high external electric field

    SciTech Connect (OSTI)

    Djurabekova, Flyura Ruzibaev, Avaz; Parviainen, Stefan; Holmstrm, Eero; Hakala, Mikko

    2013-12-28

    Metal surfaces operated under high electric fields produce sparks even if they are held in ultra high vacuum. In spite of extensive research on the topic of vacuum arcs, the mystery of vacuum arc origin still remains unresolved. The indications that the sparking rates depend on the material motivate the research on surface response to extremely high external electric fields. In this work by means of density-functional theory calculations we analyze the redistribution of electron density on (100) Cu surfaces due to self-adatoms and in presence of high electric fields from ?1?V/nm up to ?2?V/nm (?1 to ?2 GV/m, respectively). We also calculate the partial charge induced by the external field on a single adatom and a cluster of two adatoms in order to obtain reliable information on charge redistribution on surface atoms, which can serve as a benchmarking quantity for the assessment of the electric field effects on metal surfaces by means of molecular dynamics simulations. Furthermore, we investigate the modifications of work function around rough surface features, such as step edges and self-adatoms.

  11. Optical spectroscopy of sputtered nanometer-thick yttrium iron garnet films

    SciTech Connect (OSTI)

    Jakubisova-Liskova, Eva Visnovsky, Stefan; Chang, Houchen; Wu, Mingzhong

    2015-05-07

    Nanometer (nm)-thick yttrium iron garnet (Y{sub 3}Fe{sub 5}O{sub 12}, YIG) films present interest for spintronics. This work employs spectral ellipsometry and magneto-optic Kerr effect (MOKE) spectra to characterize nm-thick YIG films grown on single-crystal Gd{sub 3}Ga{sub 5}O{sub 12} substrates by magnetron sputtering. The thickness (t) of the films ranges between 10 nm and 40 nm. Independent on t, the polar MOKE hysteresis loops saturate in the field of about 1.8 kOe, consistent with the saturation magnetization in bulk YIG (4πM{sub s} ≈ 1.75 kG). The MOKE spectrum measured at photon energies between 1.3 eV and 4.5 eV on the 38-nm-thick film agrees with that measured on single-crystal YIG bulk materials. The MOKE spectrum of the 12-nm-thick film still preserves the structure of the bulk YIG but its amplitude at lower photon energies is modified due to the fact that the radiation penetration depth exceeds 20 nm. The t dependence of the MOKE amplitude is consistent with MOKE calculations. The results indicate that the films are stoichiometric, strain free, without Fe{sup 2+}, and preserve bulk YIG properties down to t ≈ 10 nm.

  12. Anisotropic fibrous thermal insulator of relatively thick cross section and method for making same

    DOE Patents [OSTI]

    Reynolds, Carl D.; Ardary, Zane L.

    1979-01-01

    The present invention is directed to an anisotropic thermal insulator formed of carbon-bonded organic or inorganic fibers and having a thickness or cross section greater than about 3 centimeters. Delaminations and deleterious internal stresses generated during binder curing and carbonizing operations employed in the fabrication of thick fibrous insulation of thicknesses greater than 3 centimeters are essentially obviated by the method of the present invention. A slurry of fibers, thermosetting resin binder and water is vacuum molded into the selected insulator configuration with the total thickness of the molded slurry being less than about 3 centimeters, the binder is thermoset to join the fibers together at their nexaes, and then the binder is carbonized to form the carbon bond. A second slurry of the fibers, binder and water is then applied over the carbonized body with the vacuum molding, binder thermosetting and carbonizing steps being repeated to form a layered insulator with the binder providing a carbon bond between the layers. The molding, thermosetting and carbonizing steps may be repeated with additional slurries until the thermal insulator is of the desired final thickness. An additional feature of the present invention is provided by incorporating opacifying materials in any of the desired layers so as to provide different insulating properties at various temperatures. Concentration and/or type of additive can be varied from layer-to-layer.

  13. Thick adherent dielectric films on plastic substrates and method for depositing same

    DOE Patents [OSTI]

    Wickboldt, Paul; Ellingboe, Albert R.; Theiss, Steven D.; Smith, Patrick M.

    2002-01-01

    Thick adherent dielectric films deposited on plastic substrates for use as a thermal barrier layer to protect the plastic substrates from high temperatures which, for example, occur during laser annealing of layers subsequently deposited on the dielectric films. It is desirable that the barrier layer has properties including: a thickness of 1 .mu.m or greater, adheres to a plastic substrate, does not lift-off when cycled in temperature, has few or no cracks and does not crack when subjected to bending, resistant to lift-off when submersed in fluids, electrically insulating and preferably transparent. The thick barrier layer may be composed, for example, of a variety of dielectrics and certain metal oxides, and may be deposited on a variety of plastic substrates by various known deposition techniques. The key to the method of forming the thick barrier layer on the plastic substrate is maintaining the substrate cool during deposition of the barrier layer. Cooling of the substrate maybe accomplished by the use of a cooling chuck on which the plastic substrate is positioned, and by directing cooling gas, such as He, Ar and N.sub.2, between the plastic substrate and the cooling chucks. Thick adherent dielectric films up to about 5 .mu.m have been deposited on plastic substrates which include the above-referenced properties, and which enable the plastic substrates to withstand laser processing temperatures applied to materials deposited on the dielectric films.

  14. Thickness and UV irradiation effects on the gas sensing properties of Te thin films

    SciTech Connect (OSTI)

    Manouchehrian, M.; Larijani, M.M.; Elahi, S.M.

    2015-02-15

    Highlights: • Tellurium thin films were prepared by thermal evaporation technique. • Tellurium thin films showed excellent gas-sensing properties to H{sub 2}S at room temperature. • Tellurium showed a remarkably enhanced response to H{sub 2}S gas under UV irradiation. • The reason of the enhanced response by UV irradiation was discussed. - Abstract: In this research, tellurium thin films were investigated for use as hydrogen sulfide gas sensors. To this end, a tellurium thin film has been deposited on Al{sub 2}O{sub 3} substrates by thermal evaporation, and the influence of thickness on the sensitivity of the tellurium thin film for measuring H{sub 2}S gas is studied. XRD patterns indicate that as the thickness increases, the crystallization improves. Observing the images obtained by SEM, it is seen that the grain size increases as the thickness increases. Studying the effect of thickness on H{sub 2}S gas measurement, it became obvious that as the thickness increases, the sensitivity decreases and the response and recovery times increase. To improve the response and recovery times of the tellurium thin film for measuring H{sub 2}S gas, the influence of UV radiation while measuring H{sub 2}S gas was also investigated. The results indicate that the response and recovery times strongly decrease using UV radiation.

  15. Method and apparatus for ultrasonic characterization through the thickness direction of a moving web

    DOE Patents [OSTI]

    Jackson, Theodore; Hall, Maclin S.

    2001-01-01

    A method and apparatus for determining the caliper and/or the ultrasonic transit time through the thickness direction of a moving web of material using ultrasonic pulses generated by a rotatable wheel ultrasound apparatus. The apparatus includes a first liquid-filled tire and either a second liquid-filled tire forming a nip or a rotatable cylinder that supports a thin moving web of material such as a moving web of paper and forms a nip with the first liquid-filled tire. The components of ultrasonic transit time through the tires and fluid held within the tires may be resolved and separately employed to determine the separate contributions of the two tire thicknesses and the two fluid paths to the total path length that lies between two ultrasonic transducer surfaces contained within the tires in support of caliper measurements. The present invention provides the benefit of obtaining a transit time and caliper measurement at any point in time as a specimen passes through the nip of rotating tires and eliminates inaccuracies arising from nonuniform tire circumferential thickness by accurately retaining point-to-point specimen transit time and caliper variation information, rather than an average obtained through one or more tire rotations. Morever, ultrasonic transit time through the thickness direction of a moving web may be determined independent of small variations in the wheel axle spacing, tire thickness, and liquid and tire temperatures.

  16. Thickness of surficial sediment at and near the Idaho National Engineering Laboratory, Idaho

    SciTech Connect (OSTI)

    Anderson, S.R.; Liszewski, M.J.; Ackerman, D.J.

    1996-06-01

    Thickness of surficial sediment was determined from natural-gamma logs in 333 wells at and near the Idaho National Engineering Laboratory in eastern Idaho to provide reconnaissance data for future site-characterization studies. Surficial sediment, which is defined as the unconsolidated clay, silt, sand, and gravel that overlie the uppermost basalt flow at each well, ranges in thickness from 0 feet in seven wells drilled through basalt outcrops east of the Idaho Chemical Processing Plant to 313 feet in well Site 14 southeast of the Big Lost River sinks. Surficial sediment includes alluvial, lacustrine, eolian, and colluvial deposits that generally accumulated during the past 200 thousand years. Additional thickness data, not included in this report, are available from numerous auger holes and foundation borings at and near most facilities.

  17. Thickness-dependent metal-insulator transition in epitaxial SrRuO3 ultrathin films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shen, Xuan; Qiu, Xiangbiao; Su, Dong; Zhou, Shengqiang; Li, Aidong; Wu, Di

    2015-01-06

    Transport characteristics of ultrathin SrRuO₃ films, deposited epitaxially on TiO₂-terminated SrTiO₃ (001) single-crystal substrates, were studied as a function of film thickness. Evolution from a metallic to an insulating behavior is observed as the film thickness decreases from 20 to 4 unit cells. In films thicker than 4 unit cells, the transport behavior obeys the Drude low temperature conductivity with quantum corrections, which can be attributed to weak localization. Fitting the data with 2-dimensional localization model indicates that electron-phonon collisions are the main inelastic relaxation mechanism. In the film of 4 unit cells in thickness, the transport behavior follows variablemore » range hopping model, indicating a strongly localized state. As a result, magnetoresistance measurements reveal a likely magnetic anisotropy with the magnetic easy axis along the out-of-plane direction.« less

  18. Thickness-dependent metal-insulator transition in epitaxial SrRuO? ultrathin films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shen, Xuan; Qiu, Xiangbiao; Su, Dong; Zhou, Shengqiang; Li., Aidong; Wu, Di

    2015-01-06

    Transport characteristics of ultrathin SrRuO? films, deposited epitaxially on TiO?-terminated SrTiO? (001) single-crystal substrates, were studied as a function of film thickness. Evolution from a metallic to an insulating behavior is observed as the film thickness decreases from 20 to 4 unit cells. In films thicker than 4 unit cells, the transport behavior obeys the Drude low temperature conductivity with quantum corrections, which can be attributed to weak localization. Fitting the data with 2-dimensional localization model indicates that electron-phonon collisions are the main inelastic relaxation mechanism. In the film of 4 unit cells in thickness, the transport behavior follows variablemorerange hopping model, indicating a strongly localized state. Magnetoresistance measurements reveal a likely magnetic anisotropy with the magnetic easy axis along the out-of-plane direction.less

  19. Investigation of damage behavior of thermally sprayed coatings depending on coating thickness

    SciTech Connect (OSTI)

    Crostack, H.A.; Beller, U.

    1995-12-31

    In order to increase the lifetime of components used for diesel engines or gas turbines surfaces are coated by ceramics. In recent years it succeeded in spraying thermal barrier coatings based on zirconia up to a thickness of a few millimeters. A comparison of the damage behavior between yttria partially stabilized zirconia coatings with different thickness will be presented. The coatings are produced by atmospheric plasma spraying. The thickness is varied from 0.5 mm up to 2 mm. In order to characterize the mechanical as well as the damage processes different methods of destructive testing (tensile, bending, and loading test) are applied. Additionally, non-destructive testing methods were used to investigate the damage processes on micro structural level. The results will be discussed according to the microstructure.

  20. Physicochemical controls on absorbed water film thickness in unsaturated geological media

    SciTech Connect (OSTI)

    Tokunaga, T.

    2011-06-14

    Adsorbed water films commonly coat mineral surfaces in unsaturated soils and rocks, reducing flow and transport rates. Therefore, it is important to understand how adsorbed film thickness depends on matric potential, surface chemistry, and solution chemistry. Here, the problem of adsorbed water film thickness is examined through combining capillary scaling with the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Novel aspects of this analysis include determining capillary influences on film thicknesses, and incorporating solution chemistry-dependent electrostatic potential at air-water interfaces. Capillary analysis of monodisperse packings of spherical grains provided estimated ranges of matric potentials where adsorbed films are stable, and showed that pendular rings within drained porous media retain most of the 'residual' water except under very low matric potentials. Within drained pores, capillary contributions to thinning of adsorbed films on spherical grains are shown to be small, such that DLVO calculations for flat surfaces are suitable approximations. Hamaker constants of common soil minerals were obtained to determine ranges of the dispersion component to matric potential-dependent film thickness. The pressure component associated with electrical double layer forces was estimated using the compression and linear superposition approximations. The pH-dependent electrical double layer pressure component is the dominant contribution to film thicknesses at intermediate values of matric potential, especially in lower ionic strength solutions (< 10 mol m{sup -3}) on surfaces with higher magnitude electrostatic potentials (more negative than - 50 mV). Adsorbed water films are predicted to usually range in thickness from 1 to 20 nm in drained pores and fractures of unsaturated environments.

  1. Resistive switching in a few nanometers thick tantalum oxide film formed by a metal oxidation

    SciTech Connect (OSTI)

    Ohno, Takeo; Samukawa, Seiji

    2015-04-27

    Resistive switching in a Cu/Ta{sub 2}O{sub 5}/Pt structure that consisted of a few nanometer-thick Ta{sub 2}O{sub 5} film was demonstrated. The Ta{sub 2}O{sub 5} film with thicknesses of 25?nm was formed with a combination of Ta metal film deposition and neutral oxygen particle irradiation at room temperature. The device exhibited a bipolar resistive switching with a threshold voltage of 0.2?V and multilevel switching operation.

  2. Nanoscale selective area growth of thick, dense, uniform, In-rich, InGaN

    Office of Scientific and Technical Information (OSTI)

    nanostructure arrays on GaN/sapphire template (Journal Article) | SciTech Connect Nanoscale selective area growth of thick, dense, uniform, In-rich, InGaN nanostructure arrays on GaN/sapphire template Citation Details In-Document Search Title: Nanoscale selective area growth of thick, dense, uniform, In-rich, InGaN nanostructure arrays on GaN/sapphire template Authors: Sundaram, S. [1] ; Puybaret, R. [2] ; El Gmili, Y. [1] ; Li, X. [2] ; Bonanno, P. L. [1] ; Pantzas, K. [3] Search SciTech

  3. Method and apparatus for determining diameter and wall thickness of minute hollow spherical shells

    DOE Patents [OSTI]

    Steinman, David A.

    1982-01-01

    Method and apparatus for determining diameter and wall thickness of hollow microspheres or shells wherein terminal velocities of shells traveling in fluid-filled conduits of differing diameters are measured. A wall-effect factor is determined as a ratio of the terminal velocities, and shell outside diameter may then be ascertained as a predetermined empirical function of wall-effect factor. For shells of known outside diameter, wall thickness may then be ascertained as a predetermined empirical function of terminal velocity in either conduit.

  4. Aqueous Synthesis of Zinc Blende CdTe/CdS Magic-Core/Thick-Shell

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tetrahedral Shaped Nanocrystals with Emission Tunable to Near-Infrared Aqueous Synthesis of Zinc Blende CdTe/CdS Magic-Core/Thick-Shell Tetrahedral Shaped Nanocrystals with Emission Tunable to Near-Infrared Authors: Deng, Z., Schulz, O., Lin, S., Ding, B., Liu, X., Wei, X., Ros, R., Liu, Y., Yan, H., and Francis, M. Title: Aqueous Synthesis of Zinc Blende CdTe/CdS Magic-Core/Thick-Shell Tetrahedral Shaped Nanocrystals with Emission Tunable to Near-Infrared Source: Journal of the American

  5. Tuning thermoelectricity in a Bi2Se3 topological insulator via varied film thickness

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Guo, Minghua; Wang, Zhenyu; Xu, Yong; Huang, Huaqing; Zang, Yunyi; Liu, Chang; Duan, Wenhui; Gan, Zhongxue; Zhang, Shou-Cheng; He, Ke; et al

    2016-01-12

    We report thermoelectric transport studies on Bi2Se3 topological insulator thin films with varied thickness grown by molecular beam epitaxy. We find that the Seebeck coefficient and thermoelectric power factor decrease systematically with the reduction of film thickness. These experimental observations can be explained quantitatively by theoretical calculations based on realistic electronic band structure of the Bi2Se3 thin films. Lastly, this work illustrates the crucial role played by the topological surface states on the thermoelectric transport of topological insulators, and sheds new light on further improvement of their thermoelectric performance.

  6. Method and apparatus for determining diameter and wall thickness of minute hollow spherical shells

    DOE Patents [OSTI]

    Steinman, D.A.

    1980-05-30

    Method and apparatus for determining diameter and wall thickness of hollow microspheres or shells wherein terminal velocities of shells traveling in fluid-filled conduits of differing diameters are measured. A wall-effect factor is determined as a ratio of the terminal velocities, and shell outside diameter may then be ascertained as a predetermined empirical function of wall-effect factor. For shells of known outside diameter, wall thickness may then be ascertained as a predetermined empirical function of terminal velocity in either conduit.

  7. Thick-shell nanocrystal quantum dots (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Patent: Thick-shell nanocrystal quantum dots Citation Details In-Document Search Title: Thick-shell nanocrystal quantum dots Colloidal nanocrystal quantum dots comprising an inner core having an average diameter of at least 1.5 nm and an outer shell, where said outer shell comprises multiple monolayers, wherein at least 30% of the quantum dots have an on-time fraction of 0.80 or greater under continuous excitation conditions for a period of time of at least 10 minutes. Authors: Hollingsworth,

  8. Thickness-dependent charge transport in few-layer MoS 2 field-effect

    Office of Scientific and Technical Information (OSTI)

    transistors (Journal Article) | SciTech Connect Thickness-dependent charge transport in few-layer MoS 2 field-effect transistors Citation Details In-Document Search This content will become publicly available on March 10, 2017 Title: Thickness-dependent charge transport in few-layer MoS 2 field-effect transistors Authors: Lin, Ming-Wei ; Kravchenko, Ivan I. ; Fowlkes, Jason ; Li, Xufan ; Puretzky, Alexander A. ; Rouleau, Christopher M. ; Geohegan, David B. ; Xiao, Kai Publication Date:

  9. Thickness-dependent coherent phonon frequency in ultrathin FeSe/SrTiO3

    Office of Scientific and Technical Information (OSTI)

    films (Journal Article) | SciTech Connect Thickness-dependent coherent phonon frequency in ultrathin FeSe/SrTiO3 films Citation Details In-Document Search Title: Thickness-dependent coherent phonon frequency in ultrathin FeSe/SrTiO3 films Ultrathin FeSe films grown on SrTiO3 substrates are a recent milestone in atomic material engineering due to their important role in understanding unconventional superconductivity in Fe-based materials. By using femtosecond time- and angle-resolved

  10. Thickness-dependent coherent phonon frequency in ultrathin FeSe/SrTiO3

    Office of Scientific and Technical Information (OSTI)

    films (Journal Article) | SciTech Connect Thickness-dependent coherent phonon frequency in ultrathin FeSe/SrTiO3 films Citation Details In-Document Search Title: Thickness-dependent coherent phonon frequency in ultrathin FeSe/SrTiO3 films × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information

  11. Application of Spray Foam Insulation Under Plywood and Oriented Strand Board Roof Sheathing

    SciTech Connect (OSTI)

    Grin, A. [Building Science Corporation, Somerville, MA (United States); Smegal, J. [Building Science Corporation, Somerville, MA (United States); Lstiburek, J. [Building Science Corporation, Somerville, MA (United States)

    2013-10-01

    Unvented roof strategies with open cell and closed cell spray polyurethane foam insulation sprayed to the underside of roof sheathing have been used since the mid-1990's to provide durable and efficient building enclosures. However, there have been isolated moisture related incidents reported anecdotally that raise potential concerns about the overall hygrothermal performance of these systems. This project involved hygrothermal modeling of a range of rainwater leakage and field evaluations of in-service residential roofs using spray foam insulation. All of the roof assemblies modeled exhibited drying capacity to handle minor rainwater leakage. All field evaluation locations of in-service residential roofs had moisture contents well within the safe range for wood-based sheathing. Explorations of eleven in-service roof systems were completed. The exploration involved taking a sample of spray foam from the underside of the roof sheathing, exposing the sheathing, then taking a moisture content reading. All locations had moisture contents well within the safe range for wood-based sheathing. One full-roof failure was reviewed, as an industry partner was involved with replacing structurally failed roof sheathing. In this case the manufacturer's investigation report concluded that the spray foam was installed on wet OSB based on the observation that the spray foam did not adhere well to the substrate and the pore structure of the closed cell spray foam at the ccSPF/OSB interface was indicative of a wet substrate.

  12. Application of Spray Foam Insulation Under Plywood and Oriented Strand Board Roof Sheathing

    SciTech Connect (OSTI)

    Grin, A.; Smegal, J.; Lstiburek, J.

    2013-10-01

    Unvented roof strategies with open cell and closed cell spray polyurethane foam insulation sprayed to the underside of roof sheathing have been used since the mid-1990's to provide durable and efficient building enclosures. However, there have been isolated moisture related incidents reported anecdotally that raise potential concerns about the overall hygrothermal performance of these systems. The incidents related to rainwater leakage and condensation concerns. Condensation concerns have been extensively studied by others and are not further discussed in this report. This project involved hygrothermal modeling of a range of rainwater leakage and field evaluations of in-service residential roofs using spray foam insulation. All of the roof assemblies modeled exhibited drying capacity to handle minor rainwater leakage. All field evaluation locations of in-service residential roofs had moisture contents well within the safe range for wood-based sheathing. Explorations of eleven in-service roof systems were completed. The exploration involved taking a sample of spray foam from the underside of the roof sheathing, exposing the sheathing, then taking a moisture content reading. All locations had moisture contents well within the safe range for wood-based sheathing. One full-roof failure was reviewed, as an industry partner was involved with replacing structurally failed roof sheathing. In this case the manufacturer's investigation report concluded that the spray foam was installed on wet OSB based on the observation that the spray foam did not adhere well to the substrate and the pore structure of the closed cell spray foam at the ccSPF/OSB interface was indicative of a wet substrate.

  13. Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01

    Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks for roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. This project directly investigated rain and indirectly investigated built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.

  14. Technology Solutions Case Study: Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing

    SciTech Connect (OSTI)

    2013-11-01

    Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks for roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. In this project, Building Science Corporation investigated rain and built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.

  15. High-pressure structure made of rings with peripheral weldments of reduced thickness

    DOE Patents [OSTI]

    Leventry, Samuel C.

    1988-01-01

    A high-pressure structure having a circular cylindrical metal shell made of metal rings joined together by weldments and which have peripheral areas of reduced shell thickness at the weldments which permit a reduction in the amount of weld metal deposited while still maintaining sufficient circumferential or hoop stress strength.

  16. Thermal Conductivity Measurement of Xe-Implanted Uranium Dioxide Thick Films using Multilayer Laser Flash Analysis

    SciTech Connect (OSTI)

    Nelson, Andrew T.

    2012-08-30

    The Fuel Cycle Research and Development program's Advanced Fuels campaign is currently pursuing use of ion beam assisted deposition to produce uranium dioxide thick films containing xenon in various morphologies. To date, this technique has provided materials of interest for validation of predictive fuel performance codes and to provide insight into the behavior of xenon and other fission gasses under extreme conditions. In addition to the structural data provided by such thick films, it may be possible to couple these materials with multilayer laser flash analysis in order to measure the impact of xenon on thermal transport in uranium dioxide. A number of substrate materials (single crystal silicon carbide, molybdenum, and quartz) containing uranium dioxide films ranging from one to eight microns in thickness were evaluated using multilayer laser flash analysis in order to provide recommendations on the most promising substrates and geometries for further investigation. In general, the uranium dioxide films grown to date using ion beam assisted deposition were all found too thin for accurate measurement. Of the substrates tested, molybdenum performed the best and looks to be the best candidate for further development. Results obtained within this study suggest that the technique does possess the necessary resolution for measurement of uranium dioxide thick films, provided the films are grown in excess of fifty microns. This requirement is congruent with the material needs when viewed from a fundamental standpoint, as this length scale of material is required to adequately sample grain boundaries and possible second phases present in ceramic nuclear fuel.

  17. Temperature effects on failure thickness and deflagration-to-detonation transition in PBX 9502 and TATB

    SciTech Connect (OSTI)

    Asay, B.W.; McAfee, J.B.

    1993-01-01

    The deflagration-to-detonation (DDT) behavior of TATB has been investigated at high temperatures and severe confinement. comparison is made to other common explosives under similar confinement. TATB did not DDT under these conditions. The failure thickness of PBX 9502 at 250[degrees]C has also been determined. Two mm appears to be the limiting value at this temperature.

  18. Temperature effects on failure thickness and deflagration-to-detonation transition in PBX 9502 and TATB

    SciTech Connect (OSTI)

    Asay, B.W.; McAfee, J.B.

    1993-04-01

    The deflagration-to-detonation (DDT) behavior of TATB has been investigated at high temperatures and severe confinement. comparison is made to other common explosives under similar confinement. TATB did not DDT under these conditions. The failure thickness of PBX 9502 at 250{degrees}C has also been determined. Two mm appears to be the limiting value at this temperature.

  19. SU-E-I-53: Variation in Measurements of Breast Skin Thickness Obtained Using Different Imaging Modalities

    SciTech Connect (OSTI)

    Nguyen, U; Kumaraswamy, N; Markey, M

    2014-06-01

    Purpose: To investigate variation in measurements of breast skin thickness obtained using different imaging modalities, including mammography, computed tomography (CT), ultrasound, and magnetic resonance imaging (MRI). Methods: Breast skin thicknesses as measured by mammography, CT, ultrasound, and MRI were compared. Mammographic measurements of skin thickness were obtained from published studies that utilized standard positioning (upright) and compression. CT measurements of skin thickness were obtained from a published study of a prototype breast CT scanner in which the women were in the prone position and the breast was uncompressed. Dermatological ultrasound exams of the breast skin were conducted at our institution, with the subjects in the upright position and the breast uncompressed. Breast skin thickness was calculated from breast MRI exams at our institution, with the patient in the prone position and the breast uncompressed. Results: T tests for independent samples demonstrated significant differences in the mean breast skin thickness as measured by different imaging modalities. Repeated measures ANOVA revealed significant differences in breast skin thickness across different quadrants of the breast for some modalities. Conclusion: The measurement of breast skin thickness is significantly different across different imaging modalities. Differences in the amount of compression and differences in patient positioning are possible reasons why measurements of breast skin thickness vary by modality.

  20. Thickness independent reduced forming voltage in oxygen engineered HfO{sub 2} based resistive switching memories

    SciTech Connect (OSTI)

    Sharath, S. U. Kurian, J.; Komissinskiy, P.; Hildebrandt, E.; Alff, L.; Bertaud, T.; Walczyk, C.; Calka, P.; Schroeder, T.

    2014-08-18

    The conducting filament forming voltage of stoichiometric hafnium oxide based resistive switching layers increases linearly with layer thickness. Using strongly reduced oxygen deficient hafnium oxide thin films grown on polycrystalline TiN/Si(001) substrates, the thickness dependence of the forming voltage is strongly suppressed. Instead, an almost constant forming voltage of about 3?V is observed up to 200?nm layer thickness. This effect suggests that filament formation and switching occurs for all samples in an oxidized HfO{sub 2} surface layer of a few nanometer thickness while the highly oxygen deficient thin film itself merely serves as a oxygen vacancy reservoir.

  1. Evaluation of Cadmium-Free Thick Film Materials on Alumina Substrates

    SciTech Connect (OSTI)

    L. H. Perdieu

    2009-09-01

    A new cadmium-free material system was successfully evaluated for the fabrication of thick film hybrid microcircuits at Honeywell Federal Manufacturing & Technologies (FM&T). The characterization involved screen printing, drying and firing two groups of resistor networks which were made using the current material system and the cadmium-free material system. Electrical, environmental and adhesion tests were performed on both groups to determine the more suitable material system. Additionally, untrimmed test coupons were evaluated to further characterize the new materials. The cadmiumfree material system did as well or better than the current material system. Therefore, the new cadmium-free material system was approved for use on production thick film product.

  2. Effects of catalyst film thickness on plasma-enhanced carbon nanotube growth

    SciTech Connect (OSTI)

    Hofmann, S.; Cantoro, M.; Kleinsorge, B.; Casiraghi, C.; Parvez, A.; Robertson, J.; Ducati, C.

    2005-08-01

    A systematic study is presented of the influence of catalyst film thickness on carbon nanostructures grown by plasma-enhanced chemical-vapor deposition from acetylene and ammonia mixtures. We show that reducing the Fe/Co catalyst film thickness below 3 nm causes a transition from larger diameter (>40 nm), bamboolike carbon nanofibers to small diameter ({approx}5 nm) multiwalled nanotubes with two to five walls. This is accompanied by a more than 50 times faster growth rate and a faster catalyst poisoning. Thin Ni catalyst films only trigger such a growth transition when pretreated with an ammonia plasma. We observe a limited correlation between this growth transition and the coarsening of the catalyst film before deposition. For a growth temperature of {<=}550 deg. C, all catalysts showed mainly a tip growth regime and a similar activity on untreated silicon, oxidized silicon, and silicon nitride support.

  3. Neutron-skin thickness from the study of the anti-analog giant dipole resonance

    SciTech Connect (OSTI)

    Krasznahorkay, A.; Stuhl, L.; Csatlos, M.; Algora, A.; and others

    2012-10-20

    The {gamma}-decay of the anti-analog of the giant dipole resonance (AGDR) to the isobaric analog state has been measured following the p({sup 124}Sn,n) reaction at a beam energy of 600 MeV/nucleon. The energy of the transition was also calculated with state-of-the-art self-consistent relativistic random-phase approximation (RPA) and turned out to be very sensitive to the neutronskin thickness ({Delta}R{sub pn}). By comparing the theoretical results with the measured one, the {Delta}R{sub pn} value for {sup 124}Sn was deduced to be 0.21 {+-} 0.07 fm, which agrees well with the previous results. The present method offers new possibilities for measuring the neutron-skin thicknesses of very exotic isotopes.

  4. Post-cast EDM method for reducing the thickness of a turbine nozzle wall

    DOE Patents [OSTI]

    Jones, Raymond Joseph (Duanesburg, NY); Bojappa, Parvangada Ganapathy (Schenectady, NY); Kirkpatrick, Francis Lawrence (Galway, NY); Schotsch, Margaret Jones (Clifton Park, NY); Rajan, Rajiv (Guilderland, NY); Wei, Bin (Mechanicville, NY)

    2002-01-01

    A post-cast EDM process is used to remove material from the interior surface of a nozzle vane cavity of a turbine. A thin electrode is passed through the cavity between opposite ends of the nozzle vane and displaced along the interior nozzle wall to remove the material along a predetermined path, thus reducing the thickness of the wall between the cavity and the external surface of the nozzle. In another form, an EDM process employing a profile as an electrode is disposed in the cavity and advanced against the wall to remove material from the wall until the final wall thickness is achieved, with the interior wall surface being complementary to the profile surface.

  5. Thick, low-stress films, and coated substrates formed therefrom, and methods for making same

    DOE Patents [OSTI]

    Henager, Jr., Charles H.; Knoll, Robert W.

    1992-01-01

    Stress-induced deformation, and the damage resulting therefrom, increases with film thickness. The overcoming of excessive stress by the use of the Si-Al-N film material of the present invention, permits the formation of thick films that are necessary for certain of the above described applications. The most likely use for the subject film materials, other than their specialized views as an optical film, is for microelectronic packaging of components on silicon substrates. In general, the subject films have excellent adherence to the underlying substrate, a high degree of hardness and durability, and are excellent insulators. Prior art elevated temperature deposition processes cannot meet the microelectronic packaging temperature formation constraints. The process of the present invention is conducted under non-elevated temperature conditions, typically 500.degree. C. or less.

  6. Influences and interactions of inundation, peat, and snow on active layer thickness: Modeling Archive

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Scott Painter; Ethan Coon; Cathy Wilson; Dylan Harp; Adam Atchley

    2016-04-21

    This Modeling Archive is in support of an NGEE Arctic publication currently in review [4/2016]. The Advanced Terrestrial Simulator (ATS) was used to simulate thermal hydrological conditions across varied environmental conditions for an ensemble of 1D models of Arctic permafrost. The thickness of organic soil is varied from 2 to 40cm, snow depth is varied from approximately 0 to 1.2 meters, water table depth was varied from -51cm below the soil surface to 31 cm above the soil surface. A total of 15,960 ensemble members are included. Data produced includes the third and fourth simulation year: active layer thickness, time of deepest thaw depth, temperature of the unfrozen soil, and unfrozen liquid saturation, for each ensemble member. Input files used to run the ensemble are also included.

  7. Method for rapid, controllable growth and thickness, of epitaxial silicon films

    DOE Patents [OSTI]

    Wang, Qi; Stradins, Paul; Teplin, Charles; Branz, Howard M.

    2009-10-13

    A method of producing epitaxial silicon films on a c-Si wafer substrate using hot wire chemical vapor deposition by controlling the rate of silicon deposition in a temperature range that spans the transition from a monohydride to a hydrogen free silicon surface in a vacuum, to obtain phase-pure epitaxial silicon film of increased thickness is disclosed. The method includes placing a c-Si substrate in a HWCVD reactor chamber. The method also includes supplying a gas containing silicon at a sufficient rate into the reaction chamber to interact with the substrate to deposit a layer containing silicon thereon at a predefined growth rate to obtain phase-pure epitaxial silicon film of increased thickness.

  8. Fermion resonances on a thick brane with a piecewise warp factor

    SciTech Connect (OSTI)

    Li Haitao; Liu Yuxiao; Zhao Zhenhua; Guo Heng

    2011-02-15

    In this paper, we mainly investigate the problems of resonances of massive Kaluza-Klein (KK) fermions on a single scalar constructed thick brane with a piecewise warp factor matching smoothly. The distance between two boundaries and the other parameters are determined by one free parameter through three junction conditions. For the generalized Yukawa coupling {eta}{Psi}{phi}{sup k{Psi}} with odd k=1,3,5,..., the mass eigenvalue m, width {Gamma}, lifetime {tau}, and maximal probability P{sub max} of fermion resonances are obtained. Our numerical calculations show that the brane without internal structure also favors the appearance of resonant states for both left- and right-handed fermions. The scalar-fermion coupling and the thickness of the brane influence the resonant behaviors of the massive KK fermions.

  9. Ferroelectric polymer-ceramic composite thick films for energy storage applications

    SciTech Connect (OSTI)

    Singh, Paritosh; Borkar, Hitesh; Singh, B. P.; Singh, V. N.; Kumar, Ashok

    2014-08-15

    We have successfully fabricated large area free standing polyvinylidene fluoride -Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} (PVDF-PZT) ferroelectric polymer-ceramic composite (wt% 8020, respectively) thick films with an average diameter (d) ?0.1 meter and thickness (t) ?50 ?m. Inclusion of PZT in PVDF matrix significantly enhanced dielectric constant (from 10 to 25 at 5 kHz) and energy storage capacity (from 11 to 14 J/cm{sup 3}, using polarization loops), respectively, and almost similar leakage current and mechanical strength. Microstructural analysis revealed the presence of ? and ? crystalline phases and homogeneous distribution of PZT crystals in PVDF matrix. It was also found that apart from the microcrystals, well defined naturally developed PZT nanocrystals were embedded in PVDF matrix. The observed energy density indicates immense potential in PVDF-PZT composites for possible applications as green energy and power density electronic elements.

  10. Thickness effects on the plastic collapse of perforated plates with triangular penetration patterns

    SciTech Connect (OSTI)

    Gordon, J.L.; Jones, D.P.; Holliday, J.E.

    2000-03-01

    This paper investigates the effects of plate thickness on the accuracy of limit load solutions obtained using an elastic-perfectly plastic [EPP] equivalent solid [EQS] procedure for flat perforated plates with a triangular array of penetrations. The EQS approach for limit loads is based on an EQS collapse surface that is valid for generalized plane strain. This assumption is applicable for very thick plates but is known to be less reasonable for very thin plates where plane stress may be a better assumption. The limits of applicability of the generalized plane strain assumption are investigated by obtaining limit load solutions for perforated plates of various thicknesses that are subjected to in-plane and bending loads. Plastic limit load solutions obtained using three-dimensional EPP finite element analysis [FEA] of models which include each penetration explicitly are compared with solutions obtained using the EQS approximation. The penetration pattern chosen for this study has a ligament efficiency (ligament width-to-pitch ratio, h/P) of 0.32. For plates thicker than the pitch, the limit load calculated using the EQS method for both in-plane and bending loads is shown to be very accurate (within 4%) of the limit load calculated for the explicit model. On the other hand, for thin plates (t/P< 2), the EQS limit load is 5% greater than the explicit limit load for bending and 8% greater than the explicit limit load for in-plane loads. For thinner plates, the collapse surface is tied to the local geometry deformation and, hence, an equivalent solid plate representation of plastic collapse is a function of deformation mode and thickness.

  11. Method of manufacturing hollow members having uniform wall thickness through use of ablation

    DOE Patents [OSTI]

    Anderson, Paul R.; Downs, Raymond L.; Henderson, Timothy M.

    1982-01-01

    A method of manufacturing a hollow structure of uniform wall thickness comprising the steps of selecting or forming a precursor having one wall surface of desired geometry, treating a portion of the precursor consisting of the one wall surface and a uniform depth of material beneath the wall surface to increase resistance to ablation, and then removing by ablation and discarding the remaining or untreated portion of the precursor.

  12. Quasi-Rayleigh waves in butt-welded thick steel plate

    SciTech Connect (OSTI)

    Kamas, Tuncay E-mail: victorg@sc.edu Giurgiutiu, Victor E-mail: victorg@sc.edu Lin, Bin E-mail: victorg@sc.edu

    2015-03-31

    This paper discusses theoretical and experimental analyses of weld guided surface acoustic waves (SAW) through the guided wave propagation (GWP) analyses. The GWP analyses have been carried out by utilizing piezoelectric wafer active sensors (PWAS) for in situ structural inspection of a thick steel plate with butt weld as the weld bead is ground flush. Ultrasonic techniques are commonly used for validation of welded structures in many in-situ monitoring applications, e.g. in off-shore structures, in nuclear and pressure vessel industries and in a range of naval applications. PWAS is recently employed in such ultrasonic applications as a resonator as well as a transducer. Quasi-Rayleigh waves a.k.a. SAW can be generated in relatively thick isotropic elastic plate having the same phase velocity as Rayleigh waves whereas Rayleigh waves are a high frequency approximation of the first symmetric (S0) and anti-symmetric (A0) Lamb wave modes. As the frequency becomes very high the S0 and the A0 wave speeds coalesce, and both have the same value. This value is exactly the Rayleigh wave speed and becomes constant along the frequency i.e. Rayleigh waves are non-dispersive guided surface acoustic waves. The study is followed with weld-GWP tests through the pitch-catch method along the butt weld line. The tuning curves of quasi-Rayleigh wave are determined to show the tuning and trapping effect of the weld bead that has higher thickness than the adjacent plates on producing a dominant quasi-Rayleigh wave mode. The significant usage of the weld tuned and guided quasi-Rayleigh wave mode is essentially discussed for the applications in the in-situ inspection of relatively thick structures with butt weld such as naval offshore structures. The paper ends with summary, conclusions and suggestions for future work.

  13. Unique Challenges Accompany Thick-Shell CdSe/nCdS (n > 10) Nanocrystal Synthesis

    SciTech Connect (OSTI)

    Guo, Y; Marchuk, K; Abraham, R; Sampat, S; Abraham, R.; Fang, N; Malko, AV; Vela, J

    2011-12-23

    Thick-shell CdSe/nCdS (n {ge} 10) nanocrystals were recently reported that show remarkably suppressed fluorescence intermittency or 'blinking' at the single-particle level as well as slow rates of Auger decay. Unfortunately, whereas CdSe/nCdS nanocrystal synthesis is well-developed up to n {le} 6 CdS monolayers (MLs), reproducible syntheses for n {ge} 10 MLs are less understood. Known procedures sometimes result in homogeneous CdS nucleation instead of heterogeneous, epitaxial CdS nucleation on CdSe, leading to broad and multimodal particle size distributions. Critically, obtained core/shell sizes are often below those desired. This article describes synthetic conditions specific to thick-shell growth (n {ge} 10 and n {ge} 20 MLs) on both small (sub2 nm) and large (>4.5 nm) CdSe cores. We find added secondary amine and low concentration of CdSe cores and molecular precursors give desired core/shell sizes. Amine-induced, partial etching of CdSe cores results in apparent shell-thicknesses slightly beyond those desired, especially for very-thick shells (n {ge} 20 MLs). Thermal ripening and fast precursor injection lead to undesired homogeneous CdS nucleation and incomplete shell growth. Core/shells derived from small CdSe (1.9 nm) have longer PL lifetimes and more pronounced blinking at single-particle level compared with those derived from large CdSe (4.7 nm). We expect our new synthetic approach will lead to a larger throughput of these materials, increasing their availability for fundamental studies and applications.

  14. Effects of Volcanism, Crustal Thickness, and Large Scale Faulting on the

    Broader source: Energy.gov (indexed) [DOE]

    Development and Evolution of Geothermal Systems: Collaborative Project in Chile | Department of Energy Effects of Volcanism, Crustal Thickness, and Large Scale Faulting on the Development and Evolution of Geothermal Systems: Collaborative Project in Chile presentation at the April 2013 peer review meeting held in Denver, Colorado. PDF icon collaborative_project_chile_peer2013.pdf More Documents & Publications track 2: hydrothermal | geothermal 2015 peer review Blind Geothermal System

  15. MULTIPLICITY OF NOVA ENVELOPE SOLUTIONS AND OCCURRENCE OF OPTICALLY THICK WINDS

    SciTech Connect (OSTI)

    Kato, Mariko; Hachisu, Izumi E-mail: hachisu@ea.c.u-tokyo.ac.jp

    2009-07-10

    We revisit the occurrence condition of optically thick winds reported by Kato in 1985 and Kato and Hachisu in 1989 who mathematically examined nova envelope solutions with an old opacity and found that optically thick winds are accelerated only in massive white dwarfs (WDs) of {approx}>0.9 M{sub sun}. With the OPAL opacity we find that the optically thick wind occurs for {approx}>0.6 M{sub sun} WDs and that the occurrence of winds depends not only on the WD mass but also on the ignition mass. When the ignition mass is larger than a critical value, winds are suppressed by a density-inversion layer. Such a static solution can be realized in WDs of mass {approx}0.6-0.7 M{sub sun}. We propose that sequences consisting only of static solutions correspond to slow evolutions in symbiotic novae like PU Vul because PU Vul shows no indication of strong winds in a long-lasted flat peak followed by a very slow decline in its light curve.

  16. Thickness controlled sol-gel silica films for plasmonic bio-sensing devices

    SciTech Connect (OSTI)

    Figus, Cristiana Quochi, Francesco Artizzu, Flavia Saba, Michele Marongiu, Daniela Mura, Andrea; Bongiovanni, Giovanni; Floris, Francesco; Marabelli, Franco; Patrini, Maddalena; Fornasari, Lucia; Pellacani, Paola; Valsesia, Andrea

    2014-10-21

    Plasmonics has recently received considerable interest due to its potentiality in many fields as well as in nanobio-technology applications. In this regard, various strategies are required for modifying the surfaces of plasmonic nanostructures and to control their optical properties in view of interesting application such as bio-sensing, We report a simple method for depositing silica layers of controlled thickness on planar plasmonic structures. Tetraethoxysilane (TEOS) was used as silica precursor. The control of the silica layer thickness was obtained by optimizing the sol-gel method and dip-coating technique, in particular by properly tuning different parameters such as pH, solvent concentration, and withdrawal speed. The resulting films were characterized via atomic force microscopy (AFM), Fourier-transform (FT) spectroscopy, and spectroscopic ellipsometry (SE). Furthermore, by performing the analysis of surface plasmon resonances before and after the coating of the nanostructures, it was observed that the position of the resonance structures could be properly shifted by finely controlling the silica layer thickness. The effect of silica coating was assessed also in view of sensing applications, due to important advantages, such as surface protection of the plasmonic structure.

  17. A reliable control system for measurement on film thickness in copper chemical mechanical planarization system

    SciTech Connect (OSTI)

    Li, Hongkai; Qu, Zilian; Zhao, Qian; Tian, Fangxin; Zhao, Dewen; Meng, Yonggang; Lu, Xinchun

    2013-12-15

    In recent years, a variety of film thickness measurement techniques for copper chemical mechanical planarization (CMP) are subsequently proposed. In this paper, the eddy-current technique is used. In the control system of the CMP tool developed in the State Key Laboratory of Tribology, there are in situ module and off-line module for measurement subsystem. The in situ module can get the thickness of copper film on wafer surface in real time, and accurately judge when the CMP process should stop. This is called end-point detection. The off-line module is used for multi-points measurement after CMP process, in order to know the thickness of remained copper film. The whole control system is structured with two levels, and the physical connection between the upper and the lower is achieved by the industrial Ethernet. The process flow includes calibration and measurement, and there are different algorithms for two modules. In the process of software development, C++ is chosen as the programming language, in combination with Qt OpenSource to design two modules’ GUI and OPC technology to implement the communication between the two levels. In addition, the drawing function is developed relying on Matlab, enriching the software functions of the off-line module. The result shows that the control system is running stably after repeated tests and practical operations for a long time.

  18. Dynamic mask for producing uniform or graded-thickness thin films

    DOE Patents [OSTI]

    Folta, James A. (Livermore, CA)

    2006-06-13

    A method for producing single layer or multilayer films with high thickness uniformity or thickness gradients. The method utilizes a moving mask which blocks some of the flux from a sputter target or evaporation source before it deposits on a substrate. The velocity and position of the mask is computer controlled to precisely tailor the film thickness distribution. The method is applicable to any type of vapor deposition system, but is particularly useful for ion beam sputter deposition and evaporation deposition; and enables a high degree of uniformity for ion beam deposition, even for near-normal incidence of deposition species, which may be critical for producing low-defect multilayer coatings, such as required for masks for extreme ultraviolet lithography (EUVL). The mask can have a variety of shapes, from a simple solid paddle shape to a larger mask with a shaped hole through which the flux passes. The motion of the mask can be linear or rotational, and the mask can be moved to make single or multiple passes in front of the substrate per layer, and can pass completely or partially across the substrate.

  19. Dielectric sheet thickness variation and disbond detection in mulitlayered composites using an extremely sensitive microwave approach

    SciTech Connect (OSTI)

    Gray, S.; Zoughi, R.

    1997-01-01

    Accurate thickness measurement and thickness variation detection of dielectric sheets such as plastics, paper, ceramics, and rubber are important practical issues. Detection of a very thin or initiating disbond in multilayered dielectric composites, representing the earliest stage of its existence, is also very important. The use of an open ended rectangular waveguide sensor has proved to be a useful and capable approach for these purposes. The usefulness of this approach stems from the fact that two measurement parameters, the standoff distance and the frequency of operation, may be theoretically optimized and experimentally confirmed, rendering very sensitive dielectric sheet thickness variation and disbond detection. To further enhance the sensitivity of this microwave methodology, a third optimization parameter, a backgap distance, is artificially produced by placing a conducting plate behind the material under inspection. The presence of a backgap distance, properly located behind a dielectric sheet in concert with the proper choice of the operating frequency and the standoff distance, results in extremely sensitive measurements. Theoretical predictions, as well as experimental results in the frequency range of 8 to 40 GHz, indicating the utility of this approach are presented in this paper.s

  20. Weakly nonlinear Rayleigh-Taylor instability of a finite-thickness fluid layer

    SciTech Connect (OSTI)

    Wang, L. F. Ye, W. H. Liu, Jie; He, X. T.; Guo, H. Y.; Wu, J. F. Zhang, W. Y.

    2014-12-15

    A weakly nonlinear (WN) model has been developed for the Rayleigh-Taylor instability of a finite-thickness incompressible fluid layer (slab). We derive the coupling evolution equations for perturbations on the (upper) “linearly stable” and (lower) “linearly unstable” interfaces of the slab. Expressions of temporal evolutions of the amplitudes of the perturbation first three harmonics on the upper and lower interfaces are obtained. The classical feedthrough (interface coupling) solution obtained by Taylor [Proc. R. Soc. London A 201, 192 (1950)] is readily recovered by the first-order results. Our third-order model can depict the WN perturbation growth and the saturation of linear (exponential) growth of the perturbation fundamental mode on both interfaces. The dependence of the WN perturbation growth and the slab distortion on the normalized layer thickness (kd) is analytically investigated via the third-order solutions. Comparison is made with Jacobs-Catton's formula [J. W. Jacobs and I. Catton, J. Fluid Mech. 187, 329 (1988)] of the position of the “linearly unstable” interface. Using a reduced formula, the saturation amplitude of linear growth of the perturbation fundamental mode is studied. It is found that the finite-thickness effects play a dominant role in the WN evolution of the slab, especially when kd < 1. Thus, it should be included in applications where the interface coupling effects are important, such as inertial confinement fusion implosions and supernova explosions.

  1. Assessment of the single-pass thick-seam longwall mining method. Final report

    SciTech Connect (OSTI)

    Adam, R.F.J.; Douglas, W.J.

    1982-04-01

    The objectives of the project are a review of the foreign experiences in longwall mining of thick seams, an evaluation of the US thick seam reserves, a mine design, equipment specifications, and an economic study for longwall mining in a single pass up to 16 feet in US conditions. The review of foreign experience shows a steady increase in the maximum height of extraction with several examples in the range of 13 to 15 feet. Longwall face equipment is available up to an 18 feet height of extraction, based upon shields support and shearer loader. There are important reserves of thick coal seams which can be mined by a longwall in a single pass (125 billion tons). In US conditions, a retreating face with a 16 foot height of extraction and a double entry system, driven 10 feet high, are proposed. The face stability can be improved by using a two bench face cut in good geological conditions. The economic study compares longwall mining with the room-and-pillar method. Longwall mining 16 feet high coal in a single pass can compete advantageously with room-and-pillar mining. 74 figures, 14 tables.

  2. Effect of Substrate Thickness on Oxide Scale Spallation for Solid Oxide Fuel Cells

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Stephens, Elizabeth V.; Khaleel, Mohammad A.

    2011-07-01

    In this paper, the effect of the ferritic substrate's thickness on the delamination/spallation of the oxide scale was investigated experimentally and numerically. At the high-temperature oxidation environment of solid oxide fuel cells (SOFCs), a combination of growth stress with thermal stresses may lead to scale delamination/buckling and eventual spallation during SOFC stack cooling, even leading to serious degradation of cell performance. The growth stress is induced by the growth of the oxide scale on the scale/substrate interface, and thermal stress is induced by a mismatch of the coefficient of thermal expansion between the oxide scale and the substrate. The numerical results show that the interfacial shear stresses, which are the driving force of scale delamination between the oxide scale and the ferritic substrate, increase with the growth of the oxide scale and also with the thickness of the ferritic substrate; i.e., the thick ferritic substrate can easily lead to scale delamination and spallation. Experimental observation confirmed the predicted results of the delamination and spallation of the oxide scale on the ferritic substrate.

  3. The effect of mix on capsule yields as a function of shell thickness and gas fill

    SciTech Connect (OSTI)

    Bradley, P. A.

    2014-06-15

    An investigation of direct drive capsules with different shell thicknesses and gas fills was conducted to examine the amount of shock induced (Richtmyer-Meshkov) mix versus Rayleigh-Taylor mix from deceleration of the implosion. The RAGE (Eulerian) code with a turbulent mix model was used to model these capsules for neutron yields along with time-dependent mix amounts. The amount of Richtmyer-Meshkov induced mix from the shock breaking out of the shell is about 0.1??g (0.15??m of shell material), while the Rayleigh-Taylor mix is of order 1??g and determines the mixed simulation yield. The simulations were able to calculate a yield over mix (YOM) ratio (experiment/mix simulation) between 0.5 and 1.0 for capsules with shell thicknesses ranging from 7.5 to 20??m and with gas fills between 3.8 and 20?atm of D{sub 2} or DT. The simulated burn averaged T{sub ion} values typically lie with 0.5?keV of the data, which is within the measurement error. For capsules with shell thicknesses >25??m, the YOM values drop to 0.10??0.05, suggesting that some unmodeled effect needs to be accounted for in the thickest capsules.

  4. Electroplated L1{sub 0} CoPt thick-film permanent magnets

    SciTech Connect (OSTI)

    Oniku, Ololade D. Qi, Bin; Arnold, David P.

    2014-05-07

    The fabrication and magnetic characterization of 15-?m-thick electroplated L1{sub 0} CoPt hard magnets with good magnetic properties is reported in this paper. Experimental study of the dependence of the magnets' properties on annealing temperature reveals that an intrinsic coercivity H{sub ci}?=??800?kA/m (10 kOe), squareness >0.8, and energy product of >150?kJ/m{sup 3} are obtained for photolithographically patterned structures (250??m??2?mm stripes; 15??m thickness) electroplated on silicon substrates and annealed in hydrogen forming gas at 700?C. Scanning electron microscopy is used to inspect the morphology of both the as-deposited and annealed magnetic layers, and X-ray Diffractometer analysis on the magnets annealed at 700?C confirm a phase transformation to an ordered L1{sub 0} CoPt structure, with a minor phase of hcp Co. These thick films are intended for microsystems/MEMS applications.

  5. Wide-angle imaging LIDAR (WAIL): a ground-based instrument for monitoring the thickness and density of optically thick clouds.

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B.; Rohde, C. A.; Ho, Cheng,

    2001-01-01

    Traditional lidar provides little information on dense clouds beyond the range to their base (ceilometry), due to their extreme opacity. At most optical wavelengths, however, laser photons are not absorbed but merely scattered out of the beam, and thus eventually escape the cloud via multiple scattering, producing distinctive extended space- and time-dependent patterns which are, in essence, the cloud's radiative Green functions. These Green functions, essentially 'movies' of the time evolution of the spatial distribution of escaping light, are the primary data products of a new type of lidar: Wide Angle Imaging Lidar (WAIL). WAIL data can be used to infer both optical depth and physical thickness of clouds, and hence the cloud liquid water content. The instrumental challenge is to accommodate a radiance field varying over many orders of magnitude and changing over widely varying time-scales. Our implementation uses a high-speed microchannel plate/crossed delay line imaging detector system with a 60-degree full-angle field of view, and a 532 nm doubled Nd:YAG laser. Nighttime field experiments testing various solutions to this problem show excellent agreement with diffusion theory, and retrievals yield plausible values for the optical and geometrical parameters of the observed cloud decks.

  6. DETERMINATION OF LIQUID FILM THICKNESS FOLLOWING DRAINING OF CONTACTORS, VESSELS, AND PIPES IN THE MCU PROCESS

    SciTech Connect (OSTI)

    Poirier, M; Fernando Fondeur, F; Samuel Fink, S

    2006-06-06

    The Department of Energy (DOE) identified the caustic side solvent extraction (CSSX) process as the preferred technology to remove cesium from radioactive waste solutions at the Savannah River Site (SRS). As a result, Washington Savannah River Company (WSRC) began designing and building a Modular CSSX Unit (MCU) in the SRS tank farm to process liquid waste for an interim period until the Salt Waste Processing Facility (SWPF) begins operations. Both the solvent and the strip effluent streams could contain high concentrations of cesium which must be removed from the contactors, process tanks, and piping prior to performing contactor maintenance. When these vessels are drained, thin films or drops will remain on the equipment walls. Following draining, the vessels will be flushed with water and drained to remove the flush water. The draining reduces the cesium concentration in the vessels by reducing the volume of cesium-containing material. The flushing, and subsequent draining, reduces the cesium in the vessels by diluting the cesium that remains in the film or drops on the vessel walls. MCU personnel requested that Savannah River National Laboratory (SRNL) researchers conduct a literature search to identify models to calculate the thickness of the liquid films remaining in the contactors, process tanks, and piping following draining of salt solution, solvent, and strip solution. The conclusions from this work are: (1) The predicted film thickness of the strip effluent is 0.010 mm on vertical walls, 0.57 mm on horizontal walls and 0.081 mm in horizontal pipes. (2) The predicted film thickness of the salt solution is 0.015 mm on vertical walls, 0.74 mm on horizontal walls, and 0.106 mm in horizontal pipes. (3) The predicted film thickness of the solvent is 0.022 mm on vertical walls, 0.91 mm on horizontal walls, and 0.13 mm in horizontal pipes. (4) The calculated film volume following draining is: (a) Salt solution receipt tank--1.6 gallons; (b) Salt solution feed tank--1.6 gallons; (c) Decontaminated salt solution hold tank--1.6 gallons; (d) Contactor drain tank--0.40 gallons; (e) Strip effluent hold tank--0.33 gallons; (f) Decontaminated salt solution decanter--0.37 gallons; (g) Strip effluent decanter--0.14 gallons; (h) Solvent hold tank--0.30 gallon; and (i) Corrugated piping between contactors--16-21 mL. (5) After the initial vessel draining, flushing the vessels with 100 gallons of water using a spray nozzle that produces complete vessel coverage and draining the flush water reduces the source term by the following amounts: (i) Salt solution receipt tank--63X; (ii) Salt solution feed tank--63X; (iii) Decontaminated salt solution hold tank--63X; (iv) Contactor drain tank--250X; (v) Strip effluent hold tank--300X; (vi) Decontaminated salt solution decanter--270X; (vii) Strip effluent decanter--710X; (viii) Solvent hold tank--330X. Understand that these estimates of film thickness are based on laboratory testing and fluid mechanics theory. The calculations assume drainage occurs by film flow. Much of the data used to develop the models came from tests with very ''clean'' fluids. Impurities in the fluids and contaminants on the vessels walls could increase liquid holdup. The application of film thickness models and source term reduction calculations should be considered along with operational conditions and H-Tank Farm/Liquid Waste operating experience. These calculations exclude the PVV/HVAC duct work and piping, as well as other areas that area outside the scope of this report.

  7. IFE thick liquid wall chamber dynamics: Governing mechanisms andmodeling and experimental capabilities

    SciTech Connect (OSTI)

    Raffray, A.R.; Meier, W.; Abdel-Khalik, S.; Bonazza, R.; Calderoni, P.; Debonnel, C.S.; Dragojlovic, Z.; El-Guebaly, L.; Haynes,D.; Latkowski, J.; Olson, C.; Peterson, P.F.; Reyes, S.; Sharpe, P.; Tillack, M.S.; Zaghloul, M.

    2005-01-24

    For thick liquid wall concepts, it is important to understand the different mechanisms affecting the chamber dynamics and the state of the chamber prior to each shot a compared with requirements from the driver and target. These include ablation mechanisms, vapor transport and control, possible aerosol formation, as well as protective jet behavior. This paper was motivated by a town meeting on this subject which helped identify the major issues, assess the latest results, review the capabilities of existing modeling and experimental facilities with respect to addressing remaining issues, and helping guide future analysis and R&D efforts; the paper covers these exact points.

  8. Sensitivity of the electric dipole polarizability to the neutron skin thickness in {sup 208}Pb

    SciTech Connect (OSTI)

    Roca-Maza, X.; Agrawal, B. K.; Colo, G.; Nazarewicz, W.; Paar, N.; Piekarewicz, J.; Reinhard, P.-G.; Vretenar, D.

    2012-10-20

    The static dipole polarizability, {alpha}{sub D}, in {sup 208}Pb has been recently measured with highresolution via proton inelastic scattering at the Research Center for Nuclear Physics (RCNP) [1]. This observable is thought to be intimately connected with the neutron skin thickness, r{sub skin}, of the same nucleus and, more fundamentally, it is believed to be associated with the density dependence of the nuclear symmetry energy. The impact of r{sub skin} on {alpha}{sub D} in {sup 208}Pb is investigated and discussed on the basis of a large and representative set of relativistic and non-relativistic nuclear energy density functionals (EDF) [2].

  9. Asymptotic solution of light transport problems in optically thick luminescent media

    SciTech Connect (OSTI)

    ?ahin-Biryol, Derya Ilan, Boaz

    2014-06-15

    We study light transport in optically thick luminescent random media. Using radiative transport theory for luminescent media and applying asymptotic and computational methods, a corrected diffusion approximation is derived with the associated boundary conditions and boundary layer solution. The accuracy of this approach is verified for a plane-parallel slab problem. In particular, the reduced system models accurately the effect of reabsorption. The impacts of varying the Stokes shift and using experimentally measured luminescence data are explored in detail. The results of this study have application to the design of luminescent solar concentrators, fluorescence medical imaging, and optical cooling using anti-Stokes fluorescence.

  10. 1-nm-thick graphene tri-layer as the ultimate copper diffusion barrier

    SciTech Connect (OSTI)

    Nguyen, Ba-Son [Department of Mechanical Engineering, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Lin, Jen-Fin [Department of Mechanical Engineering, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Perng, Dung-Ching, E-mail: dcperng@ee.ncku.edu.tw [Institute of Microelectronics and Electrical Engineering Department, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China)

    2014-02-24

    We demonstrate the thinnest ever reported Cu diffusion barrier, a 1-nm-thick graphene tri-layer. X-ray diffraction patterns and Raman spectra show that the graphene is thermally stable at up to 750?C against Cu diffusion. Transmission electron microscopy images show that there was no inter-diffusion in the Cu/graphene/Si structure. Raman analyses indicate that the graphene may have degraded into a nanocrystalline structure at 750?C. At 800?C, the perfect carbon structure was damaged, and thus the barrier failed. The results of this study suggest that graphene could be the ultimate Cu interconnect diffusion barrier.

  11. Formation of Thick, Large-Area Nanoparticle Superlatices in Lithographically Defined Geometries

    SciTech Connect (OSTI)

    Akey, A.; Yang, L.; Lu, C.; Herman, I.P.

    2010-03-31

    Superlattices of colloidal nanocrystals hold the promise of new nanomaterials with tunable properties. The positioning and size of these structures are often poorly controlled after self-assembly from the solution phase, making studies of their properties difficult. We report the fabrication of {approx}100 layer thick, three-dimensional superlattices on a substrate with controlled lateral placement. This novel fabrication technique generates long-range order over the micrometer scale and controlled placement by employing lithographic patterning and microfluidic flow. Keywords: Nanoparticles; superlattice; self assembly; microfluidics; ordered array.

  12. Remote Spectroscopic Sounding of Liquid Water Path in Thick Clouds in Winter Conditions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Remote Spectroscopic Sounding of Liquid Water Path in Thick Clouds in Winter Conditions S. V. Dvoryashin and G. S. Golitsyn A. M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow, Russia The liquid water path (LWP) in mixed clouds is restored based on remote measurements of spectral brightness of a cloudy layer in the spectral range 2.15-2.35µm. The results of spectroscopic sounding of dense clouds sounding are presented. Introduction Since the 1980s, in A. M. Obukhov

  13. Layer thickness dependence of current induced effective fields in ferromagnetic multilayers

    SciTech Connect (OSTI)

    Kawaguchi, M. Moriyama, T.; Ono, T.; Koyama, T.; Chiba, D.

    2015-05-07

    We report the relation between current induced effective fields and ferromagnetic layer thickness. Hall measurements with rotating magnetic field show that the transverse and perpendicular effective fields have linear relations to the inverse of the magnetic moment m per area S. The results imply that both of these effective fields may originate from spin angular momentum transferring. However, the non-zero intercept of the transverse field at m/S = 0 implies that magnetization independent effects, such as Rashba effect, may contribute to transverse field.

  14. High-speed non-contact measuring apparatus for gauging the thickness of moving sheet material

    DOE Patents [OSTI]

    Grann, Eric B. (San Ramon, CA); Holcomb, David E. (Oak Ridge, TN)

    2000-01-01

    An optical measurement apparatus is provided for measuring the thickness of a moving sheet material (18). The apparatus has a pair of optical measurement systems (21, 31) attached to opposing surfaces (14, 16) of a rigid support structure (10). A pair of high-power laser diodes (20,30) and a pair of photodetector arrays (22,32) are attached to the opposing surfaces. Light emitted from the laser diodes is reflected off of the sheet material surfaces (17, 19) and received by the respective photodetector arrays. An associated method for implementing the apparatus is also provided.

  15. Liquid film thickness inside the high pressure swirl injectors: Real scale measurement and evaluation of analytical equations

    SciTech Connect (OSTI)

    Moon, Seoksu; Bae, Choongsik; Abo-Serie, Essam

    2010-02-15

    Liquid film thickness inside two swirl injectors for direct injection (DI) gasoline engines was measured at different injection pressure conditions ranging from 2.0 to 7.0 MPa and then previous analytical and empirical equations were examined from the experimental results. Based on the evaluation, a new equation for the liquid film thickness inside the swirl injectors was introduced. A direct photography using two real scale transparent nozzles and a pulsed light source was employed to measure the liquid film thickness inside the swirl injectors. The error in the liquid film thickness measurement, generated from different refractive indices among transparent nozzle, fuel and air, was estimated and corrected based on the geometric optics. Two injectors which have different nozzle diameter and nozzle length were applied to introduce a more general empirical equation for the liquid film thickness inside the pressure swirl injectors. The results showed that the liquid film thickness remains constant at the injection pressures for direct injection gasoline engines while the ratio of nozzle length to nozzle diameter (L/D) shows significant effect on the liquid film thickness. The previously introduced analytical and empirical equations for relatively low injection pressure swirl injectors overestimated the effect of injection pressure at the operating range of high pressure swirl injectors and, in addition, the effect of L/D ratio and swirler geometry was rarely considered. A new empirical equation was suggested based on the experimental results by taking into account the effects of fuel properties, nozzle diameter, nozzle length and swirler geometry. (author)

  16. Optical Reflection Spectroscopy of Thick Corrosion Layers on 304 Stainless Steel

    SciTech Connect (OSTI)

    R Castelli; P Persans; W Strohmayer; V Parkinson

    2006-03-23

    Corrosion resistant structural materials of both iron and nickel based alloys are used in the electric power industry for the construction of the coolant loops of both conventional and nuclear power generating stations. These materials, in the presence of high temperature (e.g. 287 C), high pH (e.g. 10.0 {at} 20 C) water with dissolved hydrogen will oxidize and form corrosion films that are double metal oxides (or spinels) of the form AB{sub 2}O{sub 4}. This work describes optical reflectivity techniques that have been developed to study the growth of these films in situ. The optical technique uses a dual-beam specular reflection spectrometer to measure the spectrum of reflected light in small angle (i.e. < 15{sup o}) scatter. The reflection spectra are then calibrated using a set of corrosion coupons with corrosion films that are well known. Results are compared with models based on multilayer reflection and Mie scattering from a particle size distribution. Surface roughness is found to be the dominant cause of reduced reflection as the films grow.

  17. OPTICALLY THICK H I DOMINANT IN THE LOCAL INTERSTELLAR MEDIUM: AN ALTERNATIVE INTERPRETATION TO ''DARK GAS''

    SciTech Connect (OSTI)

    Fukui, Y.; Torii, K.; Yamamoto, H.; Okamoto, R.; Hayakawa, T.; Tachihara, K.; Sano, H.; Onishi, T.

    2015-01-01

    Dark gas in the interstellar medium (ISM) is believed to not be detectable either in CO or H I radio emission, but it is detectable by other means including γ rays, dust emission, and extinction traced outside the Galactic plane at |b| > 5°. In these analyses, the 21 cm H I emission is usually assumed to be completely optically thin. We have reanalyzed the H I emission from the whole sky at |b| > 15° by considering temperature stratification in the ISM inferred from the Planck/IRAS analysis of the dust properties. The results indicate that the H I emission is saturated with an optical depth ranging from 0.5 to 3 for 85% of the local H I gas. This optically thick H I is characterized by spin temperature in the range 10 K-60 K, significantly lower than previously postulated in the literature, whereas such low temperature is consistent with emission/absorption measurements of the cool H I toward radio continuum sources. The distribution and the column density of the H I are consistent with those of the dark gas suggested by γ rays, and it is possible that the dark gas in the Galaxy is dominated by optically thick cold H I gas. This result implies that the average density of H I is 2-2.5 times higher than that derived on the optically thin assumption in the local ISM.

  18. A system for combined three-dimensional morphological and molecular analysis of thick tissue specimens

    SciTech Connect (OSTI)

    Fernandez-Gonzalez, Rodrigo; Jones, Arthur; Garcia-Rodriguez, Enrique; Yuan Chen, Ping; Idica, Adam; Lockett, Stephen J.; Barcellos-Hoff, Mary Helen; Ortiz-de-Solorzano, Carlos

    2002-04-25

    We present a new system for simultaneous morphological and molecular analysis of thick tissue samples. The system is composed of a computer assisted microscope and a JAVA-based image display, analysis and visualization program that allows acquisition, annotation, meaningful storage, three-dimensional reconstruction and analysis of structures of interest in thick sectioned tissue specimens. We describe the system in detail and illustrate its use by imaging, reconstructing and analyzing two complete tissue blocks which were differently processed and stained. One block was obtained from a ductal carcinoma in situ (DCIS) lumpectomy specimen and stained alternatively with Hematoxilyn and Eosin (H&E), and with a counterstain and fluorescence in situ hybridization (FISH) to the ERB-B2 gene. The second block contained a fully sectioned mammary gland of a mouse, stained for Histology with H&E. We show how the system greatly reduces the amount of interaction required for the acquisition and analysis and is therefore suitable for studies that require morphologically driven, wide scale (e.g., whole gland) analysis of complex tissue samples or cultures.

  19. Fluid Phase Lipid Areas and Bilayer Thicknesses of Commonly Used Phosphatidylcholines as a Function of Temperature

    SciTech Connect (OSTI)

    Kucerka, Norbert; Nieh, Mu-Ping; Katsaras, John

    2011-01-01

    The structural parameters of fluid phase bilayers composed of phosphatidylcholines with fully saturated, mixed, and branched fatty acid chains, at several temperatures, have been determined by simultaneously analyzing small-angle neutron and X-ray scattering data. Bilayer parameters, such as area per lipid and overall bilayer thickness have been obtained in conjunction with intrabilayer structural parameters (e.g. hydrocarbon region thickness). The results have allowed us to assess the effect of temperature and hydrocarbon chain composition on bilayer structure. For example, we found that for all lipids there is, not surprisingly, an increase in fatty acid chain trans-gauche isomerization with increasing temperature. Moreover, this increase in trans-gauche isomerization scales with fatty acid chain length in mixed chain lipids. However, in the case of lipids with saturated fatty acid chains, trans-gauche isomerization is increasingly tempered by attractive chain-chain van der Waals interactions with increasing chain length. Finally, our results confirm a strong dependence of lipid chain dynamics as a function of double bond position along fatty acid chains.

  20. Thickness-dependent electronlattice equilibration in laser-excited thin bismuth films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sokolowski-Tinten, K.; Li, R. K.; Reid, A. H.; Weathersby, S. P.; Quirin, F.; Chase, T.; Coffee, R.; Corbett, J.; Fry, A.; Hartmann, N.; et al

    2015-11-19

    Electronphonon coupling processes determine electronic transport properties of materials and are responsible for the transfer of electronic excess energy to the lattice. With decreasing device dimensions an understanding of these processes in nanoscale materials is becoming increasingly important. We use time-resolved electron diffraction to directly study energy relaxation in thin bismuth films after optical excitation. Precise measurements of the transient DebyeWaller-effect for various film thicknesses and over an extended range of excitation fluences allow to separate different contributions to the incoherent lattice response. While phonon softening in the electronically excited state is responsible for an immediate increase of the r.m.s.moreatomic displacement within a few hundred fs, 'ordinary' electronphonon coupling leads to subsequent heating of the material on a few ps time-scale. Moreover, the data reveal distinct changes in the energy transfer dynamics which becomes faster for stronger excitation and smaller film thickness, respectively. The latter effect is attributed to a cross-interfacial coupling of excited electrons to phonons in the substrate.less

  1. Spectrum and light curve of a supernova shock breakout through a thick Wolf-Rayet wind

    SciTech Connect (OSTI)

    Svirski, Gilad; Nakar, Ehud

    2014-06-20

    Wolf-Rayet stars are known to eject winds. Thus, when a Wolf-Rayet star explodes as a supernova, a fast (≳ 40, 000 km s{sup –1}) shock is expected to be driven through a wind. We study the signal expected from a fast supernova shock propagating through an optically thick wind and find that the electrons behind the shock driven into the wind are efficiently cooled by inverse Compton over soft photons that were deposited by the radiation-mediated shock that crossed the star. Therefore, the bolometric luminosity is comparable to the kinetic energy flux through the shock, and the spectrum is found to be a power law, whose slope and frequency range depend on the number flux of soft photons available for cooling. Wolf-Rayet supernovae that explode through a thick wind have a high flux of soft photons, producing a flat spectrum, νF {sub ν} = Const, in the X-ray range of 0.1 ≲ T ≲ 50 keV. As the shock expands into an optically thin wind, the soft photons are no longer able to cool the shock that plows through the wind, and the bulk of the emission takes the form of a standard core-collapse supernova (without a wind). However, a small fraction of the soft photons is upscattered by the shocked wind and produces a transient unique X-ray signature.

  2. Active probing of cloud thickness and optical depth using wide-angle imaging LIDAR.

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B.; Rohde, C. A.; Tellier, L. L.; Ho, Cheng,

    2002-01-01

    At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60{sup o} full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Section 2 covers the up-to-date evolution of the nighttime WAIL instrument at LANL. Section 3 reports our progress towards daytime capability for WAIL, an important extension to full diurnal cycle monitoring by means of an ultra-narrow magneto-optic atomic line filter. Section 4 describes briefly how the important cloud properties can be inferred from WAIL signals.

  3. Epitaxial patterning of nanometer-thick Y{sub 3}Fe{sub 5}O{sub...

    Office of Scientific and Technical Information (OSTI)

    Title: Epitaxial patterning of nanometer-thick Ysub 3Fesub 5Osub 12 films with low magnetic damping. Magnetic insulators such as yttrium iron garnet, Y3Fe5O12, with extremely ...

  4. Vehicle Technologies Office Merit Review 2015: Thick Low-Cost, High-Power Lithium-Ion Electrodes via Aqueous Processing

    Broader source: Energy.gov [DOE]

    Presentation given by Oak Ridge National Laboratory at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about thick low-cost,...

  5. a-Si{sub x}C{sub 1?x}:H thin films with subnanometer surface roughness for biological applications

    SciTech Connect (OSTI)

    Herrera-Celis, Jos Reyes-Betanzo, Claudia Itzmoyotl-Toxqui, Adrin; Ordua-Daz, Abdu Prez-Coyotl, Ana

    2015-09-15

    The characterization of a-Si{sub x}C{sub 1?x}:H thin films by plasma-enhanced chemical vapor deposition with high hydrogen dilution for biological applications is addressed. A root mean square roughness less than 1?nm was measured via atomic force microscopy for an area of 25??m{sup 2}. Structural analysis was done using Fourier transform infrared spectroscopy in the middle infrared region. It was found that under the deposition conditions, the formation of SiC bonds is promoted. Electrical dark conductivity measurements were performed to evaluate the effect of high hydrogen dilution and to find the relation between carrier transport properties and the structural arrangement. Conductivities of the order of 10{sup ?7} to 10{sup ?9} S/cm at room temperature for methanesilane gas flow ratio from 0.35 to 0.85 were achieved, respectively. UV-visible spectra were used to obtain the optical band gap and the Tauc parameter. Optical band gap as wide as 3.55?eV was achieved in the regime of high carbon incorporation. Accordingly, deposition under low power density and high hydrogen dilution reduces the roughness, improves the structure of the network, and stabilizes the film properties as a greater percentage of carbon is incorporated. The biofunctionalization of a-Si{sub x}C{sub 1?x}:H surfaces with NH{sub 2}-terminated self-assembled monolayers was obtained through silanization with 3-aminopropyltrimethoxysilane. This knowledge opens a window for the inclusion of these a-Si{sub x}C{sub 1?x}:H thin films in devices such as biosensors.

  6. Layer thickness and period as design parameters to tailor pyroelectric properties in ferroelectric superlattices

    SciTech Connect (OSTI)

    Misirlioglu, I. B.; Alpay, S. P.

    2014-10-27

    We theoretically examine the pyroelectric properties of ferroelectric-paraelectric superlattices as a function of layer thickness and configuration using non-linear thermodynamics coupled with electrostatic and electromechanical interactions between layers. We specifically study PbZr{sub 0.3}Ti{sub 0.7}O{sub 3}/SrTiO{sub 3} superlattices. The pyroelectric properties of such constructs consisting of relatively thin repeating units are shown to exceed the pyroelectric response of monolithic PbZr{sub 0.3}Ti{sub 0.7}O{sub 3} films. This is related to periodic internal electric fields generated due to the polarization mismatch between layers that allows tailoring of the shift in the transition temperature. Our results indicate that higher and electric field sensitive pyroresponse can be achieved from layer-by-layer engineered ferroelectric heterostructures.

  7. Spray shadowing for stress relief and mechanical locking in thick protective coatings

    DOE Patents [OSTI]

    Hollis, Kendall; Bartram, Brian

    2007-05-22

    A method for applying a protective coating on an article, comprising the following steps: selecting an article with a surface for applying a coating thickness; creating undercut grooves on the article, where the grooves depend beneath the surface to a bottom portion with the grooves having an upper width on the surface and a lower width on the bottom portion connected by side walls, where at least one of the side walls connects the upper width and the lower width to form an undercut angle with the surface less than 90.degree.; and, applying the protective coating onto the article to fill the undercut grooves and cover the surface, thereby forming weak paths within the protective coating.

  8. Method of controlling the side wall thickness of a turbine nozzle segment for improved cooling

    DOE Patents [OSTI]

    Burdgick, Steven Sebastian (Schenectady, NY)

    2002-01-01

    A gas turbine nozzle segment has outer and inner bands and a vane extending therebetween. Each band has a side wall, a cover and an impingement plate between the cover and nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through apertures of the impingement plate to cool the nozzle wall. The side wall of the band has an inturned flange defining with the nozzle wall an undercut region. The outer surface of the side wall is provided with a step prior to welding the cover to the side wall. A thermal barrier coating is applied in the step and, after the cover is welded to the side wall, the side wall is finally machined to a controlled thickness removing all, some or none of the coating.

  9. Fluorescence measurements for evaluating the application of multivariate analysis techniques to optically thick environments.

    SciTech Connect (OSTI)

    Reichardt, Thomas A.; Timlin, Jerilyn Ann; Jones, Howland D. T.; Sickafoose, Shane M.; Schmitt, Randal L.

    2010-09-01

    Laser-induced fluorescence measurements of cuvette-contained laser dye mixtures are made for evaluation of multivariate analysis techniques to optically thick environments. Nine mixtures of Coumarin 500 and Rhodamine 610 are analyzed, as well as the pure dyes. For each sample, the cuvette is positioned on a two-axis translation stage to allow the interrogation at different spatial locations, allowing the examination of both primary (absorption of the laser light) and secondary (absorption of the fluorescence) inner filter effects. In addition to these expected inner filter effects, we find evidence that a portion of the absorbed fluorescence is re-emitted. A total of 688 spectra are acquired for the evaluation of multivariate analysis approaches to account for nonlinear effects.

  10. Direct detection of x-rays for protein crystallography employing a thick, large area CCD

    DOE Patents [OSTI]

    Atac, Muzaffer; McKay, Timothy

    1999-01-01

    An apparatus and method for directly determining the crystalline structure of a protein crystal. The crystal is irradiated by a finely collimated x-ray beam. The interaction of the x-ray beam with the crystal produces scattered x-rays. These scattered x-rays are detected by means of a large area, thick CCD which is capable of measuring a significant number of scattered x-rays which impact its surface. The CCD is capable of detecting the position of impact of the scattered x-ray on the surface of the CCD and the quantity of scattered x-rays which impact the same cell or pixel. This data is then processed in real-time and the processed data is outputted to produce a image of the structure of the crystal. If this crystal is a protein the molecular structure of the protein can be determined from the data received.

  11. Method and apparatus for monitoring the thickness of a coal rib during rib formation

    DOE Patents [OSTI]

    Mowrey, Gary L.; Ganoe, Carl W.; Monaghan, William D.

    1996-01-01

    Apparatus for monitoring the position of a mining machine cutting a new entry in a coal seam relative to an adjacent, previously cut entry to determine the distance between a near face of the adjacent previously cut entry and a new face adjacent thereto of a new entry being cut by the mining machine which together define the thickness of a coal rib being formed between the new entry and the adjacent previously cut entry during the new entry-cutting operation. The monitoring apparatus; includes a transmit antenna mounted on the mining machine and spaced inwardly from the new face of the coal rib for transmitting radio energy towards the coal rib so that one portion of the radio energy is reflected by the new face which is defined at an air-coal interface between the new entry and the coal rib and another portion of the radio energy is reflected by the near face of the coal rib which is defined at an air-coal interface between the coal rib and the adjacent previously cut entry. A receive antenna mounted on the mining machine and spaced inwardly of the new face of the coal rib receives the one portion of the radio energy reflected by the new face and also receives the another portion of the radio energy reflected by the near face. A processor determines a first elapsed time period equal to the time required for the one portion of the radio energy reflected by the new face to travel between the transmit antenna and the receive antenna and also determines a second elapsed time period equal to the time required for the another portion of the radio energy reflected by the near face to travel between the transmit antenna and the receive antenna and thereafter calculates the thickness of the coal rib being formed as a function of the difference between the first and second elapsed time periods.

  12. Critical thickness and strain relaxation in molecular beam epitaxy-grown SrTiO{sub 3} films

    SciTech Connect (OSTI)

    Wang, Tianqi; Ganguly, Koustav; Marshall, Patrick; Xu, Peng; Jalan, Bharat

    2013-11-18

    We report on the study of the critical thickness and the strain relaxation in epitaxial SrTiO{sub 3} film grown on (La{sub 0.3}Sr{sub 0.7})(Al{sub 0.65}Ta{sub 0.35})O{sub 3} (001) (LSAT) substrate using the hybrid molecular beam epitaxy approach. No change in the film's lattice parameter (both the in-plane and the out-of-plane) was observed up to a film thickness of 180 nm, which is in sharp contrast to the theoretical critical thickness of ∼12 nm calculated using the equilibrium theory of strain relaxation. For film thicknesses greater than 180 nm, the out-of-plane lattice parameter was found to decrease hyperbolically in an excellent agreement with the relaxation via forming misfit dislocations. Possible mechanisms are discussed by which the elastic strain energy can be accommodated prior to forming misfit dislocations leading to such anomalously large critical thickness.

  13. Fabrication of TiO{sub 2} Thick Film for Photocatalyst from Commercial TiO{sub 2} Powder

    SciTech Connect (OSTI)

    Asteti, S. Fuji; Syarif, D. Gustaman

    2008-03-17

    Photocatalytic activity of TiO{sub 2} thick film ceramics made of commercial TiO{sub 2} powder has been studied. The TiO{sub 2} powder was nano sized one that was derived from dried TiO{sub 2} suspension. The TiO{sub 2} suspension was made by pouring some blended commercial TiO{sub 2} powder into some amount of water. The paste of TiO{sub 2} was made by mixing the nano sized TiO{sub 2} powder with organic vehicle and glass frit. The paste was spread on a glass substrate. The paste was dried at 100 deg. C and heated at different temperatures (400 deg. C and 500 deg. C) for 60 minutes to produce thick film ceramics. The photocatalytic activity of these films was evaluated by measuring the concentration of a solution of methylene blue where the thick films were inside after being illuminated by UV light at various periods of times. The initial concentration of the methylene blue solution was 5 ppm. Structural analyses were carried out by X-ray diffraction (XRD). The XRD analyses showed that the produced thick film ceramic had mainly crystal structure of anatase. According to the photocatalytical data, it was known that the produced thick film ceramics were photocatalyst which were capable of decomposing an organic compound such as the methylene blue.

  14. Temperature effects on nanostructure and mechanical properties of single-nanoparticle thick membranes.

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Salerno, Kenneth Michael; Grest, Gary S.

    2015-04-30

    In this study, the properties of mechanically stable single-nanoparticle (NP)-thick membranes have largely been studied at room temperature. How these membranes soften as nanoparticle ligands disorder with increasing temperature is unknown. Molecular dynamics simulations are used to probe the temperature dependence of the mechanical and nanostructural properties of nanoparticle membranes made of 6 nm diameter Au nanoparticles coated with dodecanethiol ligands and terminated with either methyl (CH3) or carboxyl (COOH) terminal groups. For methyl-terminated ligands, interactions along the alkane chain provide mechanical stiffness, with a Young's modulus of 1.7 GPa at 300 K. For carboxyl-terminated chains, end-group interactions are significant,more » producing stiffer membranes at all temperatures, with a Young's modulus of 3.8 GPa at 300 K. For both end-group types, membrane stiffness is reduced to zero at about 400 K. Ligand structure and mechanical properties of membranes at 300 K that have been annealed at 400 K are comparable to samples that do not undergo thermal annealing.« less

  15. Exploration Of Activity Measurements And Equilibrium Checks For Sediment Dating Using Thick-Window Germanium Detectors

    SciTech Connect (OSTI)

    Warner, Jacob A.; Gladkis, Laura G.; Timmers, Heiko; Fitzsimmons, Kathryn E.; Reynolds, Eva M.

    2011-06-01

    Activity measurements on sediment samples for trapped-charge geological dating using gamma-ray spectroscopy are an important verification of the field-site dose rate determination. Furthermore gamma-ray spectroscopy can check if the natural decay series are in secular equilibrium which is a crucial assumption in such dating. Typically the activities of leading members of the Thorium and Uranium decay series are measured, which requires Germanium detectors with thin windows and good energy resolution in order to effectively detect the associated low energy gamma-rays. Such equipment is not always readily available. The potential of conventional Germanium detectors with thick entrance window has been explored towards routine gamma-ray spectroscopy of sediment samples using higher energy gamma-rays. Alternative isotopes, such as Ac-228 and Pb-212 for the Thorium series, and Pa-234m, Ra-226 and Bi-214 for the Uranium series, have been measured in order to determine the mass-specific activity for the respective series and possibly provide a check of secular equilibrium. In addition to measurements of the K-40 activity, with the alternative approach, the activities of both decay series can be accurately determined. The secular equilibrium condition may be tested for the Thorium series. Measurement accuracy for Pa-234m is, however, not sufficient to permit also a reliable check of equilibrium for the Uranium series.

  16. SN 2008D: A WOLF-RAYET EXPLOSION THROUGH A THICK WIND

    SciTech Connect (OSTI)

    Svirski, Gilad; Nakar, Ehud

    2014-06-10

    Supernova (SN) 2008D/XRT 080109 is considered to be the only direct detection of a shock breakout from a regular SN to date. While a breakout interpretation was favored by several papers, inconsistencies remain between the observations and current SN shock breakout theory. Most notably, the duration of the luminous X-ray pulse is considerably longer than expected for a spherical breakout through the surface of a type Ibc SN progenitor, and the X-ray radiation features, mainly its flat spectrum and its luminosity evolution, are enigmatic. We apply a recently developed theoretical model for the observed radiation from a Wolf-Rayet SN exploding through a thick wind and show that it naturally explains all of the observed features of SN 2008D X-ray emission, including the energetics, the spectrum, and the detailed luminosity evolution. We find that the inferred progenitor and SN parameters are typical for an exploding Wolf-Rayet. A comparison of the wind density found at the breakout radius and the density at much larger radii, as inferred by late radio observations, suggests an enhanced mass-loss rate taking effect about 10days prior to the SN explosion. This finding joins accumulating evidence for a possible late phase in the stellar evolution of massive stars, involving vigorous mass loss a short time before the SN explosion.

  17. Temperature effects on nanostructure and mechanical properties of single-nanoparticle thick membranes.

    SciTech Connect (OSTI)

    Salerno, Kenneth Michael; Grest, Gary S.

    2015-04-30

    In this study, the properties of mechanically stable single-nanoparticle (NP)-thick membranes have largely been studied at room temperature. How these membranes soften as nanoparticle ligands disorder with increasing temperature is unknown. Molecular dynamics simulations are used to probe the temperature dependence of the mechanical and nanostructural properties of nanoparticle membranes made of 6 nm diameter Au nanoparticles coated with dodecanethiol ligands and terminated with either methyl (CH3) or carboxyl (COOH) terminal groups. For methyl-terminated ligands, interactions along the alkane chain provide mechanical stiffness, with a Young's modulus of 1.7 GPa at 300 K. For carboxyl-terminated chains, end-group interactions are significant, producing stiffer membranes at all temperatures, with a Young's modulus of 3.8 GPa at 300 K. For both end-group types, membrane stiffness is reduced to zero at about 400 K. Ligand structure and mechanical properties of membranes at 300 K that have been annealed at 400 K are comparable to samples that do not undergo thermal annealing.

  18. Dynamic Response of a Pulse-Heated, Thick-Walled, Hollow Sphere: Validation of Code Numerics

    SciTech Connect (OSTI)

    Canaan, R.E.

    2000-01-19

    Volumetric pulse heating of a thick-walled hollow sphere is numerically investigated. The primary objective is to validate a variety of LLNL 30 hydrocodes for modeling the dynamic behavior of fissile/fissionable metals subject to rapid ''fission-heating'' transients. The 30 codes tested include both DYNA3D and NIKE3D, as well as the ''ASCI'' code, ALE3D. The codes are compared ''head-to-head'' and are benchmarked against a 1D finite difference solution to the problem that is derived from basic principles. Three pulse-heating transients are examined with full-width-half-maximum pulse durations of 41{micro}s, 85{micro}s, and 140{micro}s, respectively. These three transients produce a significant range of dynamic responses in the thermo-elastic regime. We present results for dynamic radial displacements and stresses for each pulse, and also discuss which code features/options worked best for these types of calculations. In general, the code results are in excellent agreement for the simple system considered. Validation of code numerics in simple systems is a key first step toward future application of the codes in more complicated geometries (U).

  19. More pieces of the puzzle: chemistry and substructures in the galactic thick disk

    SciTech Connect (OSTI)

    Helmi, Amina; Williams, Mary; Freeman, K. C.; Bland-Hawthorn, J.; De Silva, G. E-mail: mary@aip.de

    2014-08-20

    We present a study of the chemical abundances of solar neighborhood stars associated with dynamical structures in the Milky Way's (thick) disk. These stars were identified as an overdensity in the eccentricity range 0.3 < ε < 0.5 in the Copenhagen-Geneva Survey by Helmi et al. We find that stars with these dynamical characteristics do not constitute a homogeneous population. A relatively sharp transition in dynamical and chemical properties appears to occur at a metallicity of [Fe/H] ∼ –0.4. Stars with [Fe/H] > –0.4 have mostly lower eccentricities, smaller vertical velocity dispersions, are α-enhanced, and define a rather narrow sequence in [α/Fe] versus [Fe/H], clearly distinct from that of the thin disk. Stars with [Fe/H] < –0.4 have a range of eccentricities, are hotter vertically, and depict a larger spread in [α/Fe]. We also found tentative evidence of a substructure possibly associated with the disruption of a metal-rich star cluster. The differences between these populations of stars is also present in, e.g., [Zn/Fe], [Ni/Fe], and [SmII/Fe], suggesting a real physical distinction.

  20. Current longwall ventilation problems and implications for thick seam longwalls. Final technical report. [133 references

    SciTech Connect (OSTI)

    Not Available

    1980-06-01

    The objective of this investigation was to identify, analyze and suggest solutions to ventilation problems of the following mining systems proposed for use in western thick seams; multiple lift longwall; single pass longwall with face height in the range of 12 to 19 feet; longwall sublevel caving. To reach this objective, background information on the regulations and ventilation practices relevant to the three methods was reviewed. This was followed by an identification of ventilation problems including the sources and quantities of methane emissions, respirable coal dust, self ignition and self heating. The problems were then analyzed to determine the probability of occurrence, the cause of the problem, and its consequences. Having analyzed these problems, solutions were described to the problems. The major finding of this effort was that, while certain ventilation difficulties can be isolated peculiar to these three moethods, in general, seam specific conditions have a larger role in determining the success of ventilation than does the method used. The major difficulties to be faced by these novel methods are the same as those to be faced by conventional longwalls. Research efforts should proceed on that basis.

  1. Thickness determination of few-layer hexagonal boron nitride films by scanning electron microscopy and Auger electron spectroscopy

    SciTech Connect (OSTI)

    Sutter, P. Sutter, E.

    2014-09-01

    We assess scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) for thickness measurements on few-layer hexagonal boron nitride (h-BN), the layered dielectric of choice for integration with graphene and other two-dimensional materials. Observations on h-BN islands with large, atomically flat terraces show that the secondary electron intensity in SEM reflects monolayer height changes in films up to least 10 atomic layers thickness. From a quantitative analysis of AES data, the energy-dependent electron escape depth in h-BN films is deduced. The results show that AES is suitable for absolute thickness measurements of few-layer h-BN of 1 to 6 layers.

  2. Thickness-dependent metal-insulator transition in epitaxial SrRuO3 ultrathin films

    SciTech Connect (OSTI)

    Shen, Xuan; Qiu, Xiangbiao; Su, Dong; Zhou, Shengqiang; Li, Aidong; Wu, Di

    2015-01-06

    Transport characteristics of ultrathin SrRuO? films, deposited epitaxially on TiO?-terminated SrTiO? (001) single-crystal substrates, were studied as a function of film thickness. Evolution from a metallic to an insulating behavior is observed as the film thickness decreases from 20 to 4 unit cells. In films thicker than 4 unit cells, the transport behavior obeys the Drude low temperature conductivity with quantum corrections, which can be attributed to weak localization. Fitting the data with 2-dimensional localization model indicates that electron-phonon collisions are the main inelastic relaxation mechanism. In the film of 4 unit cells in thickness, the transport behavior follows variable range hopping model, indicating a strongly localized state. As a result, magnetoresistance measurements reveal a likely magnetic anisotropy with the magnetic easy axis along the out-of-plane direction.

  3. Energy-loss- and thickness-dependent contrast in atomic-scale electron energy-loss spectroscopy

    SciTech Connect (OSTI)

    Tan, Haiyan; Zhu, Ye; Dwyer, Christian; Xin, Huolin L.

    2014-12-31

    Atomic-scale elemental maps of materials acquired by core-loss inelastic electron scattering often exhibit an undesirable sensitivity to the unavoidable elastic scattering, making the maps counter-intuitive to interpret. Here, we present a systematic study that scrutinizes the energy-loss and sample-thickness dependence of atomic-scale elemental maps acquired using 100 keV incident electrons in a scanning transmission electron microscope. For single-crystal silicon, the balance between elastic and inelastic scattering means that maps generated from the near-threshold Si-L signal (energy loss of 99 eV) show no discernible contrast for a thickness of 0.5? (? is the electron mean-free path, here approximately 110 nm). At greater thicknesses we observe a counter-intuitive negative contrast. Only at much higher energy losses is an intuitive positive contrast gradually restored. Our quantitative analysis shows that the energy-loss at which a positive contrast is restored depends linearly on the sample thickness. This behavior is in very good agreement with our double-channeling inelastic scattering calculations. We test a recently-proposed experimental method to correct the core-loss inelastic scattering and restore an intuitive positive chemical contrast. The method is demonstrated to be reliable over a large range of energy losses and sample thicknesses. The corrected contrast for near-threshold maps is demonstrated to be (desirably) inversely proportional to sample thickness. As a result, implications for the interpretation of atomic-scale elemental maps are discussed.

  4. Energy-loss- and thickness-dependent contrast in atomic-scale electron energy-loss spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tan, Haiyan; Zhu, Ye; Dwyer, Christian; Xin, Huolin L.

    2014-12-31

    Atomic-scale elemental maps of materials acquired by core-loss inelastic electron scattering often exhibit an undesirable sensitivity to the unavoidable elastic scattering, making the maps counter-intuitive to interpret. Here, we present a systematic study that scrutinizes the energy-loss and sample-thickness dependence of atomic-scale elemental maps acquired using 100 keV incident electrons in a scanning transmission electron microscope. For single-crystal silicon, the balance between elastic and inelastic scattering means that maps generated from the near-threshold Si-L signal (energy loss of 99 eV) show no discernible contrast for a thickness of 0.5λ (λ is the electron mean-free path, here approximately 110 nm). Atmore » greater thicknesses we observe a counter-intuitive “negative” contrast. Only at much higher energy losses is an intuitive “positive” contrast gradually restored. Our quantitative analysis shows that the energy-loss at which a positive contrast is restored depends linearly on the sample thickness. This behavior is in very good agreement with our double-channeling inelastic scattering calculations. We test a recently-proposed experimental method to correct the core-loss inelastic scattering and restore an intuitive “positive” chemical contrast. The method is demonstrated to be reliable over a large range of energy losses and sample thicknesses. The corrected contrast for near-threshold maps is demonstrated to be (desirably) inversely proportional to sample thickness. As a result, implications for the interpretation of atomic-scale elemental maps are discussed.« less

  5. In situ measurement of the bonded film thickness of Z-Tetraol lubricant on magnetic recording media

    SciTech Connect (OSTI)

    Zhu Lei; Li Feng

    2010-10-15

    Currently, the bonded film thickness of perfluoropolyether lubricant on top of magnetic recording media is measured by a two-step process. First, the media disk has to be rinsed thoroughly using a fluorocarbon solvent (for instance, Vetrel) to remove the mobile lubricant. Second, the thickness of the remaining lubricant on the media surface which is regarded as the bonded lubricant thickness is then measured either by Fourier transform infrared spectroscopy (FTIR) or electron spectroscopy for chemical analysis. As the total lubricant thickness approaches single molecular dimension ({approx}10 A), current methods face tremendous challenge on the accuracy and sensitivity of the measurement. We studied the spectral characteristics responding to the lubricant bonding with the carbon overcoat by the time-of-flight secondary ion mass spectra and proposed to use the peak area ratio (C{sub 3}H{sub 2}F/C{sub 3}H{sub 5}O and C{sub 4}H{sub 10}O/C{sub 3}H{sub 6}O{sub 2}) to characterize the bonded Z-Tetraol lubricant that produces a direct bonded lubricant thickness measurement without the need to remove the mobile lubricant with a solvent. After taking the background signal of disks prior to bonding by UV irradiation into account, this method becomes independent of the total lubricant thickness as well as shows good correlation linearity (R{sup 2{approx}}87%) with the current FTIR method for the ratio of C{sub 4}H{sub 10}O/C{sub 3}H{sub 6}O{sub 2}.

  6. Epitaxial patterning of nanometer-thick Y{sub 3}Fe{sub 5}O{sub 12} films

    Office of Scientific and Technical Information (OSTI)

    with low magnetic damping. (Journal Article) | SciTech Connect Epitaxial patterning of nanometer-thick Y{sub 3}Fe{sub 5}O{sub 12} films with low magnetic damping. Citation Details In-Document Search Title: Epitaxial patterning of nanometer-thick Y{sub 3}Fe{sub 5}O{sub 12} films with low magnetic damping. Magnetic insulators such as yttrium iron garnet, Y3Fe5O12, with extremely low magnetic damping have opened the door for low power spin-orbitronics due to their low energy dissipation and

  7. Ligand-Thickness Effect Leads to Enhanced Preference for Large Anions in Alkali Metal Extraction by Crown Ethers

    SciTech Connect (OSTI)

    Haverlock, T.J.; Moyer, B.A.; Sachleben, R.A.

    1999-07-11

    Jean-Marie Lehn (Nobel laureate, 1987) suggested ligand thickness to be an important consideration in the design of host molecules for cation recognition. We have recently expanded the role of this simple ligand property by demonstrating a case in which ligand thickness contributes significantly to anion discrimination. It was found that in the extraction of sodium nitrate and perchlorate by a simple crown ether, bis(t-octylbenzo)-14-crown-4 (BOB 14C4), the normal preference for perchlorate is almost completely lost when the complex cation has the open-face sandwich vs. the sandwich structure.

  8. Influence of the thickness of a crystal on the electrical characteristics of Cd(Zn)Te detectors

    SciTech Connect (OSTI)

    Sklyarchuk, V.; Fochuk, p.; Rarenko, I.; Zakharuk, Z.; Sklyarchuk, O. F.; Bolotnikov, A. E.; James, R. B.

    2015-08-01

    We studied the electrical characteristics of Cd(Zn)Te detectors with rectifying contacts and varying thicknesses, and established that their geometrical dimensions affect the measured electrical properties. We found that the maximum value of the operating-bias voltage and the electric field in the detector for acceptable values of the dark current can be achieved when the crystal has an optimum thickness. This finding is due to the combined effect of generation-recombination in the space-charge region and space-charge limited currents (SCLC).

  9. Laser-Arc Hybrid Welding of Thick Section Ni-base Alloys Advanced Modeling and Experiments

    SciTech Connect (OSTI)

    Debroy, Tarasankar; Palmer, Todd; Zhang, Wei

    2015-05-21

    Hybrid laser-arc welding of nickel-base alloys can increase productivity and decrease costs during construction and repair of critical components in nuclear power plants. However, laser and hybrid welding of nickel-base alloys is not well understood. This project sought to understand the physical processes during hybrid welding necessary to fabricate quality joints in Alloy 690, a Ni- Cr-Fe alloy. This document presents a summary of the data and results collected over the course of the project. The supporting documents are a collection of the research that has been or will be published in peer-reviewed journals along with a report from the partner at the national lab. Understanding the solidification behavior of Alloy 690 is important for knowing the final properties of the weldment. A study was undertaken to calculate the solidification parameters, such as temperature gradient, solidification rate, and cooling rate in Alloy 690 welds. With this information and measured cell and dendrite arm spacings, an Alloy 690 map was constructed to guide process parameter development and interpret fusion zones in later hybrid welds. This research is contained in Solidification Map of a Nickel Base Alloy. The keyhole formed under high laser intensity gives the hybrid welding technique the greater penetration depths compared to arc welding. However, keyhole behavior can form defects in the material, so knowing transient keyhole characteristics is important. With international collaborators, a study was undertaken to validate a new process monitoring tool known as inline coherent imaging (ICI), which is able to measure the keyhole depth with spatial and temporal resolutions on the order of 10 microns and 10 microseconds. ICI was validated for five alloy systems, including Alloy 690. Additionally, the keyhole growth rates at the start of welding were measured with unprecedented accuracy. This research is contained in Real Time Monitoring of Laser Beam Welding Keyhole Depth by Laser Interferometry. During full penetration welding of thick sections, root defects can form, which result in unacceptable weld quality. A study was undertaken to determine the competing forces in root defect formation by independently changing the weight forces and surface tension forces. The weight force was altered by changing the plate thickness, and the surface tension force was altered by changing the surface condition at the bottom surface. Root defects do depend on these two forces. This research is contained in Mitigation of Root Defect in Laser and Hybrid Laser-Arc Welding. Validation of the hybrid laser-arc model is necessary to properly model heat and mass transfer and fluid flow in Alloy 690 hybrid welds. Therefore, the developed model was validated for low carbon steel. Temperatures calculated by the model were included into a microstructural model in order to calculate the phase fractions. Process maps were developed for the selection of welding parameters to avoid martensite formation. This research is contained in Fusion Zone Microstructure in Full Penetration Laser-Arc Hybrid Welding of Low Alloy Steel. Alloy 690 suffers from ductility dip cracking, a form of hot cracking. This type of cracking inhibits the use of multipass welding to join Alloy 690. Our partners at ORNL performed some hot ductility testing with Alloy 690 samples using digital image correlation. The results of this work is contained in the report Summary of 690 ductility dip cracking testing using Gleeble and digital image correlation. Macro-porosity is a limiting factor in the widespread deployment of laser and hybrid laser-arc welding for construction and repair of nuclear power plant components. Keyhole instability and fluctuation results in the formation of large bubbles, which become trapped at the advancing solid- liquid interface as pores. Laser and hybrid laser-arc welds were fabricated for a range of conditions. Porosity levels in the welds were measured in X-ray computed tomography (CT), which provides very detailed data on the size and lo

  10. Study of a prototype high quantum efficiency thick scintillation crystal video-electronic portal imaging device

    SciTech Connect (OSTI)

    Samant, Sanjiv S.; Gopal, Arun

    2006-08-15

    Image quality in portal imaging suffers significantly from the loss in contrast and spatial resolution that results from the excessive Compton scatter associated with megavoltage x rays. In addition, portal image quality is further reduced due to the poor quantum efficiency (QE) of current electronic portal imaging devices (EPIDs). Commercial video-camera-based EPIDs or VEPIDs that utilize a thin phosphor screen in conjunction with a metal buildup plate to convert the incident x rays to light suffer from reduced light production due to low QE (<2% for Eastman Kodak Lanex Fast-B). Flat-panel EPIDs that utilize the same luminescent screen along with an a-Si:H photodiode array provide improved image quality compared to VEPIDs, but they are expensive and can be susceptible to radiation damage to the peripheral electronics. In this article, we present a prototype VEPID system for high quality portal imaging at sub-monitor-unit (subMU) exposures based on a thick scintillation crystal (TSC) that acts as a high QE luminescent screen. The prototype TSC system utilizes a 12 mm thick transparent CsI(Tl) (thallium-activated cesium iodide) scintillator for QE=0.24, resulting in significantly higher light production compared to commercial phosphor screens. The 25x25 cm{sup 2} CsI(Tl) screen is coupled to a high spatial and contrast resolution Video-Optics plumbicon-tube camera system (1240x1024 pixels, 250 {mu}m pixel width at isocenter, 12-bit ADC). As a proof-of-principle prototype, the TSC system with user-controlled camera target integration was adapted for use in an existing clinical gantry (Siemens BEAMVIEW{sup PLUS}) with the capability for online intratreatment fluoroscopy. Measurements of modulation transfer function (MTF) were conducted to characterize the TSC spatial resolution. The measured MTF along with measurements of the TSC noise power spectrum (NPS) were used to determine the system detective quantum efficiency (DQE). A theoretical expression of DQE(0) was developed to be used as a predictive model to propose improvements in the optics associated with the light detection. The prototype TSC provides DQE(0)=0.02 with its current imaging geometry, which is an order of magnitude greater than that for commercial VEPID systems and comparable to flat-panel imaging systems. Following optimization in the imaging geometry and the use of a high-end, cooled charge-coupled-device (CCD) camera system, the performance of the TSC is expected to improve even further. Based on our theoretical model, the expected DQE(0)=0.12 for the TSC system with the proposed improvements, which exceeds the performance of current flat-panel EPIDs. The prototype TSC provides high quality imaging even at subMU exposures (typical imaging dose is 0.2 MU per image), which offers the potential for daily patient localization imaging without increasing the weekly dose to the patient. Currently, the TSC is capable of limited frame-rate fluoroscopy for intratreatment visualization of patient motion at {approx}3 frames/second, since the achievable frame rate is significantly reduced by the limitations of the camera-control processor. With optimized processor control, the TSC is expected to be capable of intratreatment imaging exceeding 10 frames/second to monitor patient motion.

  11. Ligand structure and mechanical properties of single-nanoparticle thick membranes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Salerno, Kenneth Michael; Bolintineanu, Dan; Lane, J. Matthew; Grest, Gary S.

    2015-06-16

    We believe that the high mechanical stiffness of single-nanoparticle-thick membranes is the result of the local structure of ligand coatings that mediate interactions between nanoparticles. These ligand structures are not directly observable experimentally. We use molecular dynamics simulations to observe variations in ligand structure and simultaneously measure variations in membrane mechanical properties. We have shown previously that ligand end group has a large impact on ligand structure and membrane mechanical properties. Here we introduce and apply quantitative molecular structure measures to these membranes and extend analysis to multiple nanoparticle core sizes and ligand lengths. Simulations of nanoparticle membranes with amore » nanoparticle core diameter of 4 or 6 nm, a ligand length of 11 or 17 methylenes, and either carboxyl (COOH) or methyl (CH3) ligand end groups are presented. In carboxyl-terminated ligand systems, structure and interactions are dominated by an end-to-end orientation of ligands. In methyl-terminated ligand systems large ordered ligand structures form, but nanoparticle interactions are dominated by disordered, partially interdigitated ligands. Core size and ligand length also affect both ligand arrangement within the membrane and the membrane's macroscopic mechanical response, but are secondary to the role of the ligand end group. Additionally, the particular end group (COOH or CH3) alters the nature of how ligand length, in turn, affects the membrane properties. The effect of core size does not depend on the ligand end group, with larger cores always leading to stiffer membranes. Asymmetry in the stress and ligand density is observed in membranes during preparation at a water-vapor interface, with the stress asymmetry persisting in all membranes after drying.« less

  12. CORONAL THICK TARGET HARD X-RAY EMISSIONS AND RADIO EMISSIONS

    SciTech Connect (OSTI)

    Lee, Jeongwoo; Lim, Daye; Choe, G. S.; Kim, Kap-Sung; Jang, Minhwan

    2013-05-20

    A distinctive class of hard X-ray (HXR) sources located in the corona was recently found, which implies that the collisionally thick target model (CTTM) applies even to the corona. We investigated whether this idea can be independently verified by microwave radiations which have been known as the best companion to HXRs. This study is conducted on the GOES M2.3 class flare which occurred on 2002 September 9 and was observed by the Reuven Ramaty High-Energy Solar Spectroscopic Imager and the Owens Valley Solar Array. Interpreting the observed energy-dependent variation of HXR source size under the CTTM, the coronal density should be as high as 5 Multiplication-Sign 10{sup 11} cm{sup -3} over a distance of up to 12''. To explain the cutoff feature of the microwave spectrum at 3 GHz, however, we require a density no higher than 1 Multiplication-Sign 10{sup 11} cm{sup -3}. Additional constraints must be placed on the temperature and magnetic field of the coronal source in order to reproduce the microwave spectrum as a whole. First, a spectral feature called the Razin suppression requires a magnetic field in a range of 250-350 G along with high viewing angles around 75 Degree-Sign . Second, to avoid excess fluxes at high frequencies due to the free-free emission that was not observed, we need a high temperature {>=}2 Multiplication-Sign 10{sup 7} K. These two microwave spectral features, Razin suppression and free-free emissions, become more significant at regions of high thermal plasma density and are essential for validating and determining additional parameters of the coronal HXR sources.

  13. The effect of continuous H2S exposure on the performance of thick palladium-copper alloy membranes (book chapter)

    SciTech Connect (OSTI)

    Howard, B.H.; Cugini, A.V.; Killmeyer, R.P.; Morreale, B.D.; Enick, R.M.

    2007-03-01

    Membranes fabricated from Pd-Cu alloys containing 80, 60, and 53wt%Pd, as well as pure Pd, were exposed to flowing 1000 ppm H2S in H2 over the temperature range of 350 to 900C using three approaches to verify NETL's previously reported transient H2S exposure results. 100 um thick braze-mounted foils failed prior to 600C due to apparent sulfur attack at the braze. 1000 um thick welded membranes demonstrated similar trends as found using the transient method in that hydrogen flux through the Pd-Cu alloys with fcc structure was not significantly degraded by H2S exposure. However, both of these experimental methods suffered from possible disadvantages. The transient method had limited H2S availability and limited exposure duration, and in the 1000 um steady-state test, bulk diffusion limitations could mask effects resulting from H2S exposure. Preliminary results obtained using an alternative membrane mounting method and test protocol for steady-state testing of 100 um thick Pd and 80wt%Pd-Cu foils at 350C showed that significant flux losses occurred on exposure to flowing 1000 ppm H2S in H2, contrary to the earlier studies. Characterization showed that relatively thick sulfide layers had developed on the membrane surfaces during the 120 hours of exposure.

  14. Impact of polymer film thickness and cavity size on polymer flow during embossing : towards process design rules for nanoimprint lithography.

    SciTech Connect (OSTI)

    Schunk, Peter Randall; King, William P. (Georgia Institute of Technology, Atlanta, GA); Sun, Amy Cha-Tien; Rowland, Harry D.

    2006-08-01

    This paper presents continuum simulations of polymer flow during nanoimprint lithography (NIL). The simulations capture the underlying physics of polymer flow from the nanometer to millimeter length scale and examine geometry and thermophysical process quantities affecting cavity filling. Variations in embossing tool geometry and polymer film thickness during viscous flow distinguish different flow driving mechanisms. Three parameters can predict polymer deformation mode: cavity width to polymer thickness ratio, polymer supply ratio, and Capillary number. The ratio of cavity width to initial polymer film thickness determines vertically or laterally dominant deformation. The ratio of indenter width to residual film thickness measures polymer supply beneath the indenter which determines Stokes or squeeze flow. The local geometry ratios can predict a fill time based on laminar flow between plates, Stokes flow, or squeeze flow. Characteristic NIL capillary number based on geometry-dependent fill time distinguishes between capillary or viscous driven flows. The three parameters predict filling modes observed in published studies of NIL deformation over nanometer to millimeter length scales. The work seeks to establish process design rules for NIL and to provide tools for the rational design of NIL master templates, resist polymers, and process parameters.

  15. Thick Thermal Barrier Coatings (TTBCs) for Low Emission, High Efficiency Diesel Engine Components

    SciTech Connect (OSTI)

    M. Brad Beardsley, Caterpillar Inc.; Dr. Darrell Socie, University of Illinois; Dr. Ed Redja, University of Illinois; Dr. Christopher Berndt, State University of New York at Stony Brook

    2006-03-02

    The objective of this program was to advance the fundamental understanding of thick thermal barrier coating (TTBC) systems for application to low heat rejection diesel engine combustion chambers. Previous reviews of thermal barrier coating technology concluded that the current level of understanding of coating system behavior is inadequate and the lack of fundamental understanding may impede the application of thermal barrier coating to diesel engines.(1) Areas of TTBC technology examined in this program include powder characteristics and chemistry; bond coating composition, coating design, microstructure and thickness as they affect properties, durability, and reliability; and TTBC "aging" effects (microstructural and property changes) under diesel engine operating conditions. Fifteen TTBC ceramic powders were evaluated. These powders were selected to investigate the effects of different chemistries, different manufacturing methods, lot-to-lot variations, different suppliers and varying impurity levels. Each of the fifteen materials has been sprayed using 36 parameters selected by a design of experiments (DOE) to determine the effects of primary gas (Ar and N2), primary gas flow rate, voltage, arc current, powder feed rate, carrier gas flow rate, and spraying distance. The deposition efficiency, density, and thermal conductivity of the resulting coatings were measured. A coating with a high deposition efficiency and low thermal conductivity is desired from an economic standpoint. An optimum combination of thermal conductivity and disposition efficiency was found for each lot of powder in follow-on experiments and disposition parameters were chosen for full characterization.(2) Strengths of the optimized coatings were determined using 4-point bending specimens. The tensile strength was determined using free-standing coatings made by spraying onto mild steel substrates which were subsequently removed by chemical etching. The compressive strengths of the coatings were determined using composite specimens of ceramic coated onto stainless steel substrates, tested with the coating in compression and the steel in tension. The strength of the coating was determined from an elastic bi-material analysis of the resulting failure of the coating in compression.(3) Altough initial comparisons of the materials would appear to be straight forward from these results, the results of the aging tests of the materials are necessary to insure that trends in properties remain after long term exposure to a diesel environment. Some comparisons can be made, such as the comparison between for lot-to-lot variation. An axial fatigue test to determine the high cycle fatigue behavior of TTBCs was developed at the University of Illinois under funding from this program.(4) A fatigue test apparatus has been designed and initial work performed which demonstrates the ability to provide a routine method of axial testing of coating. The test fixture replaces the normal load frame and fixtures used to transmit the hydraulic oil loading to the sample with the TTBC specimen itself. The TTBC specimen is a composite metal/coating with stainless steel ends. The coating is sprayed onto a mild steel center tube section onto which the stainless steel ends are press fit. The specimen is then machined. After machining, the specimen is placed in an acid bath which etches the mild steel away leaving the TTBC attached to the the stainless steel ends. Plugs are then installed in the ends and the composite specimen loaded in the test fixture where the hydraulic oil pressurizes each end to apply the load. Since oil transmits the load, bending loads are minimized. This test fixture has been modified to allow piston ends to be attached to the specimen which allows tensile loading as well as compressive loading of the specimen. In addition to the room temperature data, specimens have been tested at 800 Degrees C with the surprising result that at high temperature, the TTBC exhibits much higher fatigue strength. Testing of the TTBC using tension/compression cycling has been conducted using the modified test fixture. The goal of this work was to investigate the failure mechanisms of the coating and to determine if tensile and compressive fatigue damage would interact to influence the resulting life of the coating. Coating samples were run with various mean compressive loads and constant tensile loading approximately equal to 90% of the tensile strength of the coating. The results of this testing shows no interaction of failure resulting from the tensile and compressive load. The material fails in tension at the life predicted by the maximum tensile stress or in compression at the life predicted by the compressive stress. This indicates that there are two differing failure mechanisms for the TTBC in tension and compression.

  16. 3-D Deep Penetration Neutron Imaging of Thick Absorgin and Diffusive Objects Using Transport Theory

    SciTech Connect (OSTI)

    Ragusa, Jean; Bangerth, Wolfgang

    2011-08-01

    A current area of research interest in national security is to effectively and efficiently determine the contents of the many shipping containers that enter ports in the United States. This interest comes as a result of the 9/11 Commission Act passed by Congress in 2007 that requires 100% of inbound cargo to be scanned by 2012. It appears that this requirement will be achieved by 2012, but as of February of 2009 eighty percent of the 11.5 million inbound cargo containers were being scanned. The systems used today in all major U.S. ports to determine the presence of radioactive material within cargo containers are Radiation Portal Monitors (RPM). These devices generally exist in the form of a gate or series of gates that the containers can be driven through and scanned. The monitors are effective for determining the presence of radiation, but offer little more information about the particular source. This simple pass-fail system leads to many false alarms as many everyday items emit radiation including smoke detectors due to the Americium-241 source contained inside, bananas, milk, cocoa powder and lean beef due to the trace amounts of Potassium-40, and fire brick and kitty litter due to their high clay content which often contains traces of uranium and thorium. In addition, if an illuminating source is imposed on the boundary of the container, the contents of the container may become activated. These materials include steel, aluminum and many agricultural products. Current portal monitors also have not proven to be that effective at identifying natural or highly enriched uranium (HEU). In fact, the best available Advanced Spectroscopic Portal Monitors (ASP) are only capable of identifying bare HEU 70-88% of the time and masked HEU and depleted uranium (DU) only 53 percent of the time. Therefore, a better algorithm that uses more information collected from better detectors about the specific material distribution within the container is desired. The work reported here explores the inverse problem of optical tomography applied to heterogeneous domains. The neutral particle transport equation was used as the forward model for how neutral particles stream through and interact within these heterogeneous domains. A constrained optimization technique that uses Newtons method served as the basis of the inverse problem. Optical tomography aims at reconstructing the material properties using (a) illuminating sources and (b) detector readings. However, accurate simulations for radiation transport require that the particle (gamma and/or neutron) energy be appropriate discretize in the multigroup approximation. This, in turns, yields optical tomography problems where the number of unknowns grows (1) about quadratically with respect to the number of energy groups, G, (notably to reconstruct the scattering matrix) and (2) linearly with respect to the number of unknown material regions. As pointed out, a promising approach could rely on algorithms to appropriately select a material type per material zone rather than G2 values. This approach, though promising, still requires further investigation: (a) when switching from cross-section values unknowns to material type indices (discrete integer unknowns), integer programming techniques are needed since derivative information is no longer available; and (b) the issue of selecting the initial material zoning remains. The work reported here proposes an approach to solve the latter item, whereby a material zoning is proposed using one-group or few-groups transport approximations. The capabilities and limitations of the presented method were explored; they are briefly summarized next and later described in fuller details in the Appendices. The major factors that influenced the ability of the optimization method to reconstruct the cross sections of these domains included the locations of the sources used to illuminate the domains, the number of separate experiments used in the reconstruction, the locations where measurements were collected, the optical thickness of the domain, the amount of sign

  17. The Dependence of the Strength and Thickness of Field-Aligned Currents on Solar Wind and Ionospheric Parameters

    SciTech Connect (OSTI)

    Johnson, Jay R.; Wing, Simon

    2014-08-01

    Sheared plasma flows at the low-latitude boundary layer correlate well with early afternoon auroral arcs and #12;eld-aligned currents [Sonnerup, 1980; Lundin and Evans, 1985]. We present a simple analytic model that relates solar wind and ionospheric parameters to the strength and thickness of field-aligned currents in a region of sheared velocity, such as the low latitude boundary layer. We compare the predictions of the model with DMSP observations and #12;nd remarkably good scaling of the currents with solar wind and ionospheric parameters. The sheared boundary layer thickness is inferred to be around 3000km consistent with observational studies. The analytic model provides a simple way to organize data and to infer boundary layer structures from ionospheric data.

  18. Rotational Augmentation on a 2.3 MW Rotor Blade with Thick Flatback Airfoil Cross-Sections: Preprint

    SciTech Connect (OSTI)

    Schreck, S.; Fingersh, L.; Siegel, K.; Singh, M.; Medina, P.

    2013-01-01

    Rotational augmentation was analyzed for a 2.3 MW wind turbine, which was equipped with thick flatback airfoils at inboard radial locations and extensively instrumented for acquisition of time varying surface pressures. Mean aerodynamic force and surface pressure data were extracted from an extensive field test database, subject to stringent criteria for wind inflow and turbine operating conditions. Analyses of these data showed pronounced amplification of aerodynamic forces and significant enhancements to surface pressures in response to rotational influences, relative to two-dimensional, stationary conditions. Rotational augmentation occurrence and intensity in the current effort was found to be consistent with that observed in previous research. Notably, elevated airfoil thickness and flatback design did not impede rotational augmentation.

  19. Optical monitor for real time thickness change measurements via lateral-translation induced phase-stepping interferometry

    DOE Patents [OSTI]

    Rushford, Michael C. (Livermore, CA)

    2002-01-01

    An optical monitoring instrument monitors etch depth and etch rate for controlling a wet-etching process. The instrument provides means for viewing through the back side of a thick optic onto a nearly index-matched interface. Optical baffling and the application of a photoresist mask minimize spurious reflections to allow for monitoring with extremely weak signals. A Wollaston prism enables linear translation for phase stepping.

  20. CONSTRAINTS ON COMPTON-THICK WINDS FROM BLACK HOLE ACCRETION DISKS: CAN WE SEE THE INNER DISK?

    SciTech Connect (OSTI)

    Reynolds, Christopher S.

    2012-11-01

    Strong evidence is emerging that winds can be driven from the central regions of accretion disks in both active galactic nuclei and Galactic black hole binaries. Direct evidence for highly ionized, Compton-thin inner-disk winds comes from observations of blueshifted (v {approx} 0.05-0.1c) iron-K X-ray absorption lines. However, it has been suggested that the inner regions of black hole accretion disks can also drive Compton-thick winds-such winds would enshroud the inner disk, preventing us from seeing direct signatures of the accretion disk (i.e., the photospheric thermal emission, or the Doppler/gravitationally broadened iron K{alpha} line). Here, we show that, provided the source is sub-Eddington, the well-established wind-driving mechanisms fail to launch a Compton-thick wind from the inner disk. For the accelerated region of the wind to be Compton-thick, the momentum carried in the wind must exceed the available photon momentum by a factor of at least 2/{lambda}, where {lambda} is the Eddington ratio of the source, ruling out radiative acceleration unless the source is very close to the Eddington limit. Compton-thick winds also carry large mass fluxes, and a consideration of the connections between the wind and the disk shows this to be incompatible with magneto-centrifugal driving. Finally, thermal driving of the wind is ruled out on the basis of the large Compton radii that typify black hole systems. In the absence of some new acceleration mechanisms, we conclude that the inner regions of sub-Eddington accretion disks around black holes are indeed naked.

  1. MODELING THE Fe K LINE PROFILES IN TYPE I ACTIVE GALACTIC NUCLEI WITH A COMPTON-THICK DISK WIND

    SciTech Connect (OSTI)

    Tatum, M. M.; Turner, T. J.; Sim, S. A.; Miller, L.; Reeves, J. N.; Patrick, A. R.; Long, K. S.

    2012-06-20

    We have modeled a small sample of Seyfert galaxies that were previously identified as having simple X-ray spectra with little intrinsic absorption. The sources in this sample all contain moderately broad components of Fe K-shell emission and are ideal candidates for testing the applicability of a Compton-thick accretion disk wind model to active galactic nucleus (AGN) emission components. Viewing angles through the wind allow the observer to see the absorption signature of the gas, whereas face-on viewing angles allow the observer to see the scattered light from the wind. We find that the Fe K emission line profiles are well described with a model of a Compton-thick accretion disk wind of solar abundances, arising tens to hundreds of gravitational radii from the central black hole. Further, the fits require a neutral component of Fe K{alpha} emission that is too narrow to arise from the inner part of the wind, and likely comes from a more distant reprocessing region. Our study demonstrates that a Compton-thick wind can have a profound effect on the observed X-ray spectrum of an AGN, even when the system is not viewed through the flow.

  2. Unit-cell thick BaTiO{sub 3} blocks octahedral tilt propagation across oxide heterointerface

    SciTech Connect (OSTI)

    Kan, Daisuke Aso, Ryotaro; Kurata, Hiroki; Shimakawa, Yuichi

    2014-05-14

    We fabricated SrRuO{sub 3}/BaTiO{sub 3}/GdScO{sub 3} heterostructures in which the BaTiO{sub 3} layer is one unit cell thick by pulsed laser deposition and elucidated how the BaTiO{sub 3} layer influences structural and magneto-transport properties of the SrRuO{sub 3} layer through octahedral connections across the heterointerface. Our X-ray-diffraction-based structural characterizations show that while an epitaxial SrRuO{sub 3} layer grown directly on a GdScO{sub 3} substrate is in the monoclinic phase with RuO{sub 6} octahedral tilts, a one-unit-cell-thick BaTiO{sub 3} layer inserted between SrRuO{sub 3} and GdScO{sub 3} stabilizes the tetragonal SrRuO{sub 3} layer with largely reduced RuO{sub 6} tilts. Our high-angle annular dark-field and annular bright-field scanning transmission electron microscopy observations provide an atomic-level view of the octahedral connections across the heterostructure and reveal that the BaTiO{sub 3} layer only one unit cell thick is thick enough to stabilize the RuO{sub 6}-TiO{sub 6} octahedral connections with negligible in-plane oxygen atomic displacements. This results in no octahedral tilts propagating into the SrRuO{sub 3} layer and leads to the formation of a tetragonal SrRuO{sub 3} layer. The magneto-transport property characterizations also reveal a strong impact of the octahedral connections modified by the inserted BaTiO{sub 3} layer on the spin-orbit interaction of the SrRuO{sub 3} layer. The SrRuO{sub 3} layer on BaTiO{sub 3}/ GdScO{sub 3} has in-plane magnetic anisotropy. This is in contrast to the magnetic anisotropy of the monoclinic SrRuO{sub 3} films on the GdScO{sub 3} substrate, in which the easy axis is ?45 to the film surface normal. Our results demonstrate that the one-unit-cell-thick layer of BaTiO{sub 3} can control and manipulate the interfacial octahedral connection closely linked to the structure-property relationship of heterostructures.

  3. Laser-ultrasound spectroscopy apparatus and method with detection of shear resonances for measuring anisotropy, thickness, and other properties

    DOE Patents [OSTI]

    Levesque, Daniel; Moreau, Andre; Dubois, Marc; Monchalin, Jean-Pierre; Bussiere, Jean; Lord, Martin; Padioleau, Christian

    2000-01-01

    Apparatus and method for detecting shear resonances includes structure and steps for applying a radiation pulse from a pulsed source of radiation to an object to generate elastic waves therein, optically detecting the elastic waves generated in the object, and analyzing the elastic waves optically detected in the object. These shear resonances, alone or in combination with other information, may be used in the present invention to improve thickness measurement accuracy and to determine geometrical, microstructural, and physical properties of the object. At least one shear resonance in the object is detected with the elastic waves optically detected in the object. Preferably, laser-ultrasound spectroscopy is utilized to detect the shear resonances.

  4. Focusing of dipole radiation by a negative index chiral layer. 1. A thick layer as compared with the wavelength

    SciTech Connect (OSTI)

    Guzatov, D V; Klimov, V V

    2014-09-30

    We have derived and investigated the analytical expressions for the fields of scattered radiation of an electric dipole source by a chiral (bi-isotropic) layer with arbitrary permittivity and permeability and arbitrary thickness. It is shown that in the negativeindex chiral layer the focus spot of dipole radiation is split due to excitation of right- and left-hand circularly polarised waves. The conditions are found under which the waves with one of the polarisations can be suppressed, which leads to a substantial improvement of the focusing properties of the chiral layer. (metamaterials)

  5. Annealing temperature and barrier thickness effect on the structural and optical properties of silicon nanocrystals/SiO₂ superlattices

    SciTech Connect (OSTI)

    López-Vidrier, J. Hernández, S.; López-Conesa, L.; Peiró, F.; Garrido, B.; Hiller, D.; Gutsch, S.; Zacharias, M.; Estradé, S.

    2014-10-07

    The effect of the annealing temperature and the SiO₂ barrier thickness of silicon nanocrystal (NC)/SiO₂ superlattices (SLs) on their structural and optical properties is investigated. Energy-filtered transmission electron microscopy (TEM) revealed that the SL structure is maintained for annealing temperatures up to 1150 °C, with no variation on the nanostructure morphology for different SiO₂ barrier thicknesses. Nevertheless, annealing temperatures as high as 1250 °C promote diffusion of Si atoms into the SiO₂ barrier layers, which produces larger Si NCs and the loss of the NC size control expected from the SL approach. Complementary Raman scattering measurements corroborated these results for all the SiO₂ and Si-rich oxynitride layer thicknesses. In addition, we observed an increasing crystalline fraction up to 1250 °C, which is related to a decreasing contribution of the suboxide transition layer between Si NCs and the SiO₂ matrix due to the formation of larger NCs. Finally, photoluminescence measurements revealed that the emission of the superlattices exhibits a Gaussian-like lineshape with a maximum intensity after annealing at 1150 °C, indicating a high crystalline degree in good agreement with Raman results. Samples submitted to higher annealing temperatures display a progressive emission broadening, together with an increase in the central emission wavelength. Both effects are related to a progressive broadening of the size distribution with a larger mean size, in agreement with TEM observations. On the other hand, whereas the morphology of the Si NCs is unaffected by the SiO₂ barrier thickness, the emission properties are slightly modified. These observed modifications in the emission lineshape allow monitoring the precipitation process of Si NCs in a direct non-destructive way. All these experimental results evidence that an annealing temperature of 1150 °C and 1-nm SiO₂ barrier can be reached whilst preserving the SL structure, being thus the optimal structural SL parameters for their use in optoelectronics.

  6. Photochemistry in terrestrial exoplanet atmospheres. III. Photochemistry and thermochemistry in thick atmospheres on super Earths and mini Neptunes

    SciTech Connect (OSTI)

    Hu, Renyu; Seager, Sara

    2014-03-20

    Some super Earths and mini Neptunes will likely have thick atmospheres that are not H{sub 2}-dominated. We have developed a photochemistry-thermochemistry kinetic-transport model for exploring the compositions of thick atmospheres on super Earths and mini Neptunes, applicable for both H{sub 2}-dominated atmospheres and non-H{sub 2}-dominated atmospheres. Using this model to study thick atmospheres for wide ranges of temperatures and elemental abundances, we classify them into hydrogen-rich atmospheres, water-rich atmospheres, oxygen-rich atmospheres, and hydrocarbon-rich atmospheres. We find that carbon has to be in the form of CO{sub 2} rather than CH{sub 4} or CO in a H{sub 2}-depleted water-dominated thick atmosphere and that the preferred loss of light elements from an oxygen-poor carbon-rich atmosphere leads to the formation of unsaturated hydrocarbons (C{sub 2}H{sub 2} and C{sub 2}H{sub 4}). We apply our self-consistent atmosphere models to compute spectra and diagnostic features for known transiting low-mass exoplanets GJ 1214 b, HD 97658 b, and 55 Cnc e. For GJ 1214 b, we find that (1) C{sub 2}H{sub 2} features at 1.0 and 1.5 ?m in transmission and C{sub 2}H{sub 2} and C{sub 2}H{sub 4} features at 9-14 ?m in thermal emission are diagnostic for hydrocarbon-rich atmospheres; (2) a detection of water-vapor features and a confirmation of the nonexistence of methane features would provide sufficient evidence for a water-dominated atmosphere. In general, our simulations show that chemical stability has to be taken into account when interpreting the spectrum of a super Earth/mini Neptune. Water-dominated atmospheres only exist for carbon to oxygen ratios much lower than the solar ratio, suggesting that this kind of atmospheres could be rare.

  7. Strain-relaxation and critical thickness of epitaxial La1.85Sr0.15CuO4 films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Meyer, Tricia L; Jiang, Lu; Park, Sungkyun; Egami, Takeshi; Lee, Ho Nyung

    2015-12-08

    We report the thickness-dependent strain-relaxation behavior and the associated impacts upon the superconductivity in epitaxial La1.85Sr0.15CuO4 films grown on different substrates, which provide a range of strain. We have found that the critical thickness for the onset of superconductivity in La1.85Sr0.15CuO4 films is associated with the finite thickness effect and epitaxial strain. In particular, thin films with tensile strain greater than ~0.25% revealed no superconductivity. We attribute this phenomenon to the inherent formation of oxygen vacancies that can be minimized via strain relaxation.

  8. Enhanced off-resonance magnetoelectric response in laser annealed PZT thick film grown on magnetostrictive amorphous metal substrate

    SciTech Connect (OSTI)

    Palneedi, Haribabu; Maurya, Deepam; Priya, Shashank; Kim, Gi-Yeop; Choi, Si-Young; Kang, Suk-Joong L.; Kim, Kwang-Ho; Ryu, Jungho

    2015-07-06

    A highly dense, 4 μm-thick Pb(Zr,Ti)O{sub 3} (PZT) film is deposited on amorphous magnetostrictive Metglas foil (FeBSi) by granule spray in vacuum process at room temperature, followed by its localized annealing with a continuous-wave 560 nm ytterbium fiber laser radiation. This longer-wavelength laser radiation is able to anneal the whole of thick PZT film layer without any deteriorative effects, such as chemical reaction and/or atomic diffusion, at the interface and crystallization of amorphous Metglas substrate. Greatly enhanced dielectric and ferroelectric properties of the annealed PZT are attributed to its better crystallinity and grain growth induced by laser irradiation. As a result, a colossal off-resonance magnetoelectric (ME) voltage coefficient that is two orders of magnitude larger than previously reported output from PZT/Metglas film-composites is achieved. The present work addresses the problems involved in the fabrication of PZT/Metglas film-composites and opens up emerging possibilities in employing piezoelectric materials with low thermal budget substrates (suitable for integrated electronics) and designing laminate composites for ME based devices.

  9. Bell-Plesset effects in Rayleigh-Taylor instability of finite-thickness spherical and cylindrical shells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Velikovich, A. L.; Schmit, P. F.

    2015-12-28

    Bell-Plesset (BP) effects account for the influence of global convergence or divergence of the fluid flow on the evolution of the interfacial perturbations embedded in the flow. The development of the Rayleigh-Taylor instability in radiation-driven spherical capsules and magnetically-driven cylindrical liners necessarily includes a significant contribution from BP effects due to the time dependence of the radius, velocity, and acceleration of the unstable surfaces or interfaces. An analytical model is presented that, for an ideal incompressible fluid and small perturbation amplitudes, exactly evaluates the BP effects in finite-thickness shells through acceleration and deceleration phases. The time-dependent dispersion equations determining themore » “instantaneous growth rate” are derived. It is demonstrated that by integrating this approximate growth rate over time, one can accurately evaluate the number of perturbation e-foldings during the inward acceleration phase of the implosion. As a result, in the limit of small shell thickness, exact thin-shell perturbationequations and approximate thin-shell dispersion equations are obtained, generalizing the earlier results [E. G. Harris, Phys. Fluids 5, 1057 (1962); E. Ott, Phys. Rev. Lett. 29, 1429 (1972); A. B. Bud'ko et al., Phys. Fluids B 2, 1159 (1990)].« less

  10. Bell-Plesset effects in Rayleigh-Taylor instability of finite-thickness spherical and cylindrical shells

    SciTech Connect (OSTI)

    Velikovich, A. L.; Schmit, P. F.

    2015-12-28

    Bell-Plesset (BP) effects account for the influence of global convergence or divergence of the fluid flow on the evolution of the interfacial perturbations embedded in the flow. The development of the Rayleigh-Taylor instability in radiation-driven spherical capsules and magnetically-driven cylindrical liners necessarily includes a significant contribution from BP effects due to the time dependence of the radius, velocity, and acceleration of the unstable surfaces or interfaces. An analytical model is presented that, for an ideal incompressible fluid and small perturbation amplitudes, exactly evaluates the BP effects in finite-thickness shells through acceleration and deceleration phases. The time-dependent dispersion equations determining the “instantaneous growth rate” are derived. It is demonstrated that by integrating this approximate growth rate over time, one can accurately evaluate the number of perturbation e-foldings during the inward acceleration phase of the implosion. As a result, in the limit of small shell thickness, exact thin-shell perturbationequations and approximate thin-shell dispersion equations are obtained, generalizing the earlier results [E. G. Harris, Phys. Fluids 5, 1057 (1962); E. Ott, Phys. Rev. Lett. 29, 1429 (1972); A. B. Bud'ko et al., Phys. Fluids B 2, 1159 (1990)].

  11. THE RADIAL METALLICITY GRADIENTS IN THE MILKY WAY THICK DISK AS FOSSIL SIGNATURES OF A PRIMORDIAL CHEMICAL DISTRIBUTION

    SciTech Connect (OSTI)

    Curir, A.; Serra, A. L.; Spagna, A.; Lattanzi, M. G.; Re Fiorentin, P.; Diaferio, A.

    2014-04-01

    In this Letter we examine the evolution of the radial metallicity gradient induced by secular processes, in the disk of an N-body Milky Way-like galaxy. We assign a [Fe/H] value to each particle of the simulation according to an initial, cosmologically motivated, radial chemical distribution and let the disk dynamically evolve for ∼6 Gyr. This direct approach allows us to take into account only the effects of dynamical evolution and to gauge how and to what extent they affect the initial chemical conditions. The initial [Fe/H] distribution increases with R in the inner disk up to R ≈ 10 kpc and decreases for larger R. We find that the initial chemical profile does not undergo major transformations after ∼6 Gyr of dynamical evolution. The final radial chemical gradients predicted by the model in the solar neighborhood are positive and of the same order as those recently observed in the Milky Way thick disk. We conclude that (1) the spatial chemical imprint at the time of disk formation is not washed out by secular dynamical processes and (2) the observed radial gradient may be the dynamical relic of a thick disk originated from a stellar population showing a positive chemical radial gradient in the inner regions.

  12. Outdoor Testing of GaInP2/GaAs Tandem Cells with Top Cell Thickness Varied

    SciTech Connect (OSTI)

    McMahon, W. E.; Emergy, K. E.; Friedman, D. J.; Ottoson, L.; Young, M. S.; Ward, J. S.; Kramer, C. M.; Duda, A.; Kurtz, S.

    2005-08-01

    In this study, we measure the performance of GaInP2/GaAs tandem cells under direct beam sunlight outdoors in order to quantify their sensitivity to both spectral variation and GaInP2 top-cell thickness. A set of cells with five different top-cell thicknesses was mounted on a two-axis tracker with the incident sunlight collimated to exclude all except the direct beam. Current-voltage (I-V) curves were taken throughout the course of several days, along with measurements of the direct solar spectrum. Our two major conclusions are: (1) GaInP2/GaAs tandem cells designed for either the ASTM G-173 direct (G-173D) spectrum or the "air mass 1.5 global" (AM1.5G) spectrum perform the best, and (2) cells can be characterized indoors and modeled using outdoor spectra with the same result. These results are equally valid for GaInP2/GaAs/Ge triple-junction cells.

  13. Active probing of cloud multiple scattering, optical depth, vertical thickness, and liquid water content using wide-angle imaging LIDAR.

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B.; Rohde, C. A.; Tellier, L. L.; Ho, Cheng,

    2002-01-01

    At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60-degree full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer, and, from there, estimate the volume-averaged liquid water content. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Here we present recent WAIL data oti various clouds and discuss the extension of WAIL to full diurnal monitoring by means of an ultra-narrow magneto-optic atomic line filter for daytime measurements.

  14. Reduced Cu(InGa)Se2 Thickness in Solar Cells Using a Superstrate Configuration

    SciTech Connect (OSTI)

    Shafarman, William N.

    2015-03-30

    This project by the Institute of Energy Conversion (IEC) and the Department of Electrical and Computer Engineering at the University of Delaware sought to develop the technology and underlying science to enable reduced cost of Cu(InGa)Se2 manufacturing by reducing the thickness of the Cu(InGa)Se2 absorber layer by half compared to typical production. The approach to achieve this was to use the superstrate cell configuration in which light is incident on the cell through the glass. This structure facilitates optical enhancement approaches needed to achieve high efficiency with Cu(InGa)Se2 thicknesses less than 1 µm. The primary objective was to demonstrate a Cu(InGa)Se2 cell with absorber thickness 0.5 - 0.7 µm and 17% efficiency, along with a quantitative loss analysis to define a pathway to 20% efficiency. Additional objectives were the development of stable TCO and buffer layers or contact layers to withstand the Cu(InGa)Se2 deposition temperature and of advanced optical enhancement methods. The underlying fundamental science needed to effectively transition these outcomes to large scale was addressed by extensive materials and device characterization and by development of comprehensive optical models. Two different superstrate configurations have been investigated. A frontwall cell is illuminated through the glass to the primary front junction of the device. This configuration has been used for previous efforts on superstrate Cu(InGa)Se2 but performance has been limited by interdiffusion or reaction with CdS or other buffer layers. In this project, several approaches to overcome these limitations were explored using CdS, ZnO and ZnSe buffer layers. In each case, mechanisms that limit device performance were identified using detailed characterization of the materials and junctions. Due to the junction formation difficulties, efforts were concentrated on a new backwall configuration in which light is incident through the substrate into the back of the absorber layer. The primary junction is then formed after Cu(InGa)Se2 deposition. This allows the potential benefits of superstrate cells for optical enhancement while maintaining processing advantages of the substrate configuration and avoiding the harmful effects of high temperature deposition on p-n junction formation. Backwall devices have outperformed substrate cells at absorber thicknesses of 0.1-0.5 µm through enhanced JSC due to easy incorporation of a Ag reflector and, with light incident on the absorber, the elimination of parasitic absorption in the CdS buffer. An efficiency of 9.7% has been achieved for a backwall Cu(InGa)Se2 device with absorber thickness ~0.4 μm. A critical achievement that enabled implementation of the backwall cell was the development of a transparent back contact using MoO3 or WO3. Processes for controlled deposition of each material by reactive rf sputtering from metal targets were developed. These contacts have wide bandgaps making them well-suited for application as contacts for backwall devices as well as potential use in bifacial cells and as the top cell of tandem CuInSe2-based devices. Optical enhancement will be critical for further improvements. Wet chemical texturing of ZnO films has been developed for a simple, low cost light-trapping scheme for backwall superstrate devices to enhance long wavelength quantum efficiency. An aqueous oxalic acid etch was developed and found to strongly texture sputtered ZnO with high haze ≈ 0.9 observed across the whole spectrum. And finally, advanced optical models have been developed to assist the characterization and optimization of Cu(InGa)Se2 cells with thin absorbers

  15. Influence of compensator thickness, field size, and off-axis distance on the effective attenuation coefficient of a cerrobend compensator for intensity-modulated radiation therapy

    SciTech Connect (OSTI)

    Haghparast, Abbas; Hashemi, Bijan; Eivazi, Mohammad Taghi

    2013-04-01

    Intensity-modulated radiation therapy (IMRT) can be performed by using compensators. To make a compensator for an IMRT practice, it is required to calculate the effective attenuation coefficient (?{sub eff}) of its material, which is affected by various factors. We studied the effect of the variation of the most important factors on the calculation of the ?{sub eff} of the cerrobend compensator for 6-MV photon beams, including the field size, compensator thickness, and off-axis distance. Experimental measurements were carried out at 100 cm source-to-surface distance and 10 cm depth for the 6-MV photon beams of an Elekta linac using various field size, compensator thickness, and off-axis settings. The field sizes investigated ranged from 4 4 to 25 25 cm{sup 2} and the cerrobend compensator thicknesses from 0.56 cm. For a fixed compensator thickness, variation of the ?{sub eff} with the field size ranged from 3.76.8%, with the highest value attributed to the largest compensator thickness. At the reference field size of 10 10 cm{sup 2}, the ?{sub eff} varied by 16.5% when the compensator thickness was increased from 0.56 cm. However, the variation of the ?{sub eff} with the off-axis distance was only 0.99% at this field size, whereas for the largest field size, it was more significant. Our results indicated that the compensator thickness and field size have the most significant effect on the calculation of the compensator ?{sub eff} for the 6-MV photon beam. Therefore, it is recommended to consider these parameters when calculating the compensator thickness for an IMRT practice designed for these beams. The off-axis distance had a significant effect on the calculation of the ?{sub eff} only for the largest field size. Hence, it is recommended to consider the effect of this parameter only for field sizes larger than 25 25 cm{sup 2}.

  16. FRAM isotopic analysis of uranium in thick-walled containers using high energy gamma rays and planar HPGe detectors.

    SciTech Connect (OSTI)

    Sampson, Thomas E.; Hypes, P. A.; Vo, Duc T.

    2002-01-01

    We describe the use of the Los Alamos FRAM isotopic analysis software to make the first reported measurements on thick-walled UF{sub 6} cylinders using small planar HPGe detectors of the type in common use at the IAEA. Heretofore, planar detector isotopic analysis measurements on uranium have used the 100-keV region and can be defeated by 10 mm of steel absorber. The analysis of planar detector measurements through 13-16 mm of steel shows that FRAM can successfully carry out these measurements and analysis in the 120-1024 keV energy range, a range previously thought to be the sole province of more efficient coaxial detectors. This paper describes the measurement conditions and results and also compares the results to other FRAM measurements with coaxial HPGe detectors. The technique of gamma-ray isotopic analysis of arbitrary samples is desirable for measuring the isotopic composition of uranium in UF{sub 6} cylinders because it does not require calibration with standards or knowledge of the cylinder wall thickness. The International Atomic Energy Agency (IAEA) uses the MGAU (Multi Group Analysis Uranium) uranium isotopic analysis software with planar high purity germanium (HPGe) detectors to measure the isotopic composition of uranium. Measurements on UF{sub 6} cylinders with 13-16-mm thick steel walls are usually unsuccessful because of the strong absorption of the 89-100 keV gamma rays and x-rays that MGAU requires for the measurement. This paper describes the use of the Los Alamos FRAM isotopic analysis software to make these measurements on UF{sub 6} cylinders. Uranium measurements with FRAM typically cover the energy range from 120-1001 keV and can easily be made through the walls of UF{sub 6} cylinders. While these measurements are usually performed with efficient coaxial HPGe detectors, this paper reports the first successful measurements using small planar HPGe detectors of the type in common use at the IAEA.

  17. In-situ Measurement of Low-Z Material Coating Thickness on High Z Substrate for Tokamaks

    Office of Scientific and Technical Information (OSTI)

    2 PPPL- 5042 In-situ Measurement of Low-Z Material Coating Thickness on High Z Substrate for Tokamaks D. Mueller, A.L. Roquemore, M. Jaworski, C.H. Skinner, J. Miller, A. Creely, P. Raman and D. Ruzic JULY 2014 p r i n c e t o n ■ ) PLASM A PHYSICS Y # | | I LABORATORY Prepared for the U.S. Department of Energy under Contract DE-AC02-09CH11466. P r in c e t o n P la s m a P h y s ic s L a b o r a to r y R e p o r t D is c la i m e r s F u ll L egal D iscla im er This report was p repared as an

  18. Temperature dependent DC electrical conductivity studies of ZnO nanoparticle thick films prepared by simple solution combustion method

    SciTech Connect (OSTI)

    Naveen, C. S. Jayanna, H. S. Lamani, Ashok R. Rajeeva, M. P.

    2014-04-24

    ZnO nanoparticles of different size were prepared by varying the molar ratio of glycine and zinc nitrate hexahydrate as fuel and oxidizer (F/O = 0.8, 1.11, 1.7) by simple solution combustion method. Powder samples were characterized by UV-Visible spectrophotometer, X-ray diffractometer, Scanning electron microscope (SEM). DC electrical conductivity measurements at room temperature and in the temperature range of 313-673K were carried out for the prepared thick films and it was found to increase with increase of temperature which confirms the semiconducting nature of the samples. Activation energies were calculated and it was found that, F/O molar ratio 1.7 has low E{sub AL} (Low temperature activation energy) and high E{sub AH} (High temperature activation energy) compared to other samples.

  19. Determination of filter-cake thicknesses from on-line flow measurements and gas/particle transport modeling

    SciTech Connect (OSTI)

    Smith, D.H.; Powell, V.; Ibrahim, E.; Ferer, M.; Ahmadi, G.

    1996-12-31

    The use of cylindrical candle filters to remove fine ({approx}0.005 mm) particles from hot ({approx}500- 900{degrees}C) gas streams currently is being developed for applications in advanced pressurized fluidized bed combustion (PFBC) and integrated gasification combined cycle (IGCC) technologies. Successfully deployed with hot-gas filtration, PFBC and IGCC technologies will allow the conversion of coal to electrical energy by direct passage of the filtered gases into non-ruggedized turbines and thus provide substantially greater conversion efficiencies with reduced environmental impacts. In the usual approach, one or more clusters of candle filters are suspended from a tubesheet in a pressurized (P {approx_lt}1 MPa) vessel into which hot gases and suspended particles enter, the gases pass through the walls of the cylindrical filters, and the filtered particles form a cake on the outside of each filter. The cake is then removed periodically by a backpulse of compressed air from inside the filter, which passes through the filter wall and filter cake. In various development or demonstration systems the thickness of the filter cake has proved to be an important, but unknown, process parameter. This paper describes a physical model for cake and pressure buildups between cleaning backpulses, and for longer term buildups of the ``baseline`` pressure drop, as caused by incomplete filter cleaning and/or re-entrainment. When combined with operating data and laboratory measurements of the cake porosity, the model may be used to calculate the (average) filter permeability, the filter-cake thickness and permeability, and the fraction of filter-cake left on the filter by the cleaning backpulse or re-entrained after the backpulse. When used for a variety of operating conditions (e.g., different coals, sorbents, temperatures, etc.), the model eventually may provide useful information on how the filter-cake properties depend on the various operating parameters.

  20. Electrochemical characteristics of samaria-doped ceria infiltrated strontium-doped LaMnO3 cathodes with varied thickness for yttria-stabilized zirconia electrolytes

    SciTech Connect (OSTI)

    Dong Ding; Mingyang Gonga; Chunchuan Xu; Nicholas Baxter; Yihong Li; John Zondlo; Kirk Gerdes; Xingbo Liu

    2010-11-09

    Samaria-doped ceria (SDC) infiltrated into strontium-doped LaMnO3 (LSM) cathodes with varied cathode thickness on yttria-stabilized zirconia (YSZ) were investigated via symmetrical cell, half cell, and full cell configurations. The results of the symmetrical cells showed that the interfacial polarization resistance (RP) decreased with increasing electrode thickness up to?30#2;m, and further increases in the thickness of the cathode did not cause significant variation of electrode performance. At 800 ?C, the minimum RP was around 0.05#2;cm2. The impedance spectra indicated that three main electrochemical processes existed, possibly corresponding to the oxygen ion incorporation, surface diffusion of oxygen species and oxygen adsorption and dissociation. The DC polarization on the half cells and characterization of the full cells also demonstrated a similar correlation between the electrode performance and the electrode thickness. The peak power densities of the single cells with the 10, 30, and 50-#2;m thick electrodes were 0.63, 1.16 and 1.11Wcm?2, respectively. The exchange current densities under moderate polarization are calculated and possible rate-determining steps are discussed.

  1. Welding for testability: An approach aimed at improving the ultrasonic testing of thick-walled austenitic and dissimilar metal welds

    SciTech Connect (OSTI)

    Wagner, Sabine; Dugan, Sandra [Materials Testing Institute University of Stuttgart (MPA), Pfaffenwaldring 32, 70569 Stuttgart (Germany); Barth, Martin; Schubert, Frank; Khler, Bernd [Fraunhofer Institute for Nondestructive Testing, Dresden Branch (IZFP-D), Maria-Reiche-Str. 2, 01109 Dresden (Germany)

    2014-02-18

    Austenitic and dissimilar welds in thick walled components show a coarse grained, dendritic microstructure. Therefore, ultrasonic testing has to deal with beam refraction, scattering and mode conversion effects. As a result, the testing techniques typically applied for isotropic materials yield dissatisfying results. Most approaches for improvement of ultrasonic testing have been based on modeling and improved knowledge of the complex wave propagation phenomena. In this paper, we discuss an alternative approach: is it possible to use a modified welding technology which eliminates the cause of the UT complications, i.e. the large-grained structure of the weld seams? Various modification parameters were tested, including: TIG current pulsing, additional DC and AC magnetic fields, and also additional external vibrations during welding. For all welds produced under different conditions, the grain structure of the weld seam was characterized by optical and GIUM microstructure visualizations on cross sections, wave field propagation measurements, and ultrasonic tests of correct detectability of flaws. The mechanical properties of the welds were also tested.

  2. Response of flame thickness and propagation speed under intense turbulence in spatially developing lean premixed methane–air jet flames

    SciTech Connect (OSTI)

    Sankaran, Ramanan; Hawkes, Evatt R.; Yoo, Chun Sang; Chen, Jacqueline H.

    2015-06-22

    Direct numerical simulations of three-dimensional spatially-developing turbulent Bunsen flames were performed at three different turbulence intensities. We performed these simulations using a reduced methane–air chemical mechanism which was specifically tailored for the lean premixed conditions simulated here. A planar-jet turbulent Bunsen flame configuration was used in which turbulent preheated methane–air mixture at 0.7 equivalence ratio issued through a central jet and was surrounded by a hot laminar coflow of burned products. The turbulence characteristics at the jet inflow were selected such that combustion occured in the thin reaction zones (TRZ) regime. At the lowest turbulence intensity, the conditions fall on the boundary between the TRZ regime and the corrugated flamelet regime, and progressively moved further into the TRZ regime by increasing the turbulent intensity. The data from the three simulations was analyzed to understand the effect of turbulent stirring on the flame structure and thickness. Furthermore, statistical analysis of the data showed that the thermal preheat layer of the flame was thickened due to the action of turbulence, but the reaction zone was not significantly affected. A global and local analysis of the burning velocity of the flame was performed to compare the different flames. Detailed statistical averages of the flame speed were also obtained to study the spatial dependence of displacement speed and its correlation to strain rate and curvature.

  3. Response of flame thickness and propagation speed under intense turbulence in spatially developing lean premixed methane–air jet flames

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sankaran, Ramanan; Hawkes, Evatt R.; Yoo, Chun Sang; Chen, Jacqueline H.

    2015-06-22

    Direct numerical simulations of three-dimensional spatially-developing turbulent Bunsen flames were performed at three different turbulence intensities. We performed these simulations using a reduced methane–air chemical mechanism which was specifically tailored for the lean premixed conditions simulated here. A planar-jet turbulent Bunsen flame configuration was used in which turbulent preheated methane–air mixture at 0.7 equivalence ratio issued through a central jet and was surrounded by a hot laminar coflow of burned products. The turbulence characteristics at the jet inflow were selected such that combustion occured in the thin reaction zones (TRZ) regime. At the lowest turbulence intensity, the conditions fall onmore » the boundary between the TRZ regime and the corrugated flamelet regime, and progressively moved further into the TRZ regime by increasing the turbulent intensity. The data from the three simulations was analyzed to understand the effect of turbulent stirring on the flame structure and thickness. Furthermore, statistical analysis of the data showed that the thermal preheat layer of the flame was thickened due to the action of turbulence, but the reaction zone was not significantly affected. A global and local analysis of the burning velocity of the flame was performed to compare the different flames. Detailed statistical averages of the flame speed were also obtained to study the spatial dependence of displacement speed and its correlation to strain rate and curvature.« less

  4. Response of flame thickness and propagation speed under intense turbulence in spatially developing lean premixed methane air jet flames

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sankaran, Ramanan; Hawkes, Evatt R.; Yoo, Chun Sang; Chen, Jacqueline H.

    2015-06-22

    Direct numerical simulations of three-dimensional spatially-developing turbulent Bunsen flames were performed at three different turbulence intensities. We performed these simulations using a reduced methaneair chemical mechanism which was specifically tailored for the lean premixed conditions simulated here. A planar-jet turbulent Bunsen flame configuration was used in which turbulent preheated methaneair mixture at 0.7 equivalence ratio issued through a central jet and was surrounded by a hot laminar coflow of burned products. The turbulence characteristics at the jet inflow were selected such that combustion occured in the thin reaction zones (TRZ) regime. At the lowest turbulence intensity, the conditions fall onmorethe boundary between the TRZ regime and the corrugated flamelet regime, and progressively moved further into the TRZ regime by increasing the turbulent intensity. The data from the three simulations was analyzed to understand the effect of turbulent stirring on the flame structure and thickness. Furthermore, statistical analysis of the data showed that the thermal preheat layer of the flame was thickened due to the action of turbulence, but the reaction zone was not significantly affected. A global and local analysis of the burning velocity of the flame was performed to compare the different flames. Detailed statistical averages of the flame speed were also obtained to study the spatial dependence of displacement speed and its correlation to strain rate and curvature.less

  5. In situ determination of lithium ion cathode/electrolyte thickness and composition as a function of charge

    SciTech Connect (OSTI)

    Baggetto, Loic; Browning, Jim; Tenhaeff, Wyatt E; Keum, Jong Kahk; Wood III, David L; Veith, Gabriel M

    2014-01-01

    In this work we report the first experimental in situ determination of the thickness and estimated composition of a condensed electrode/electrolyte interface at various states of charge for the high voltage Li-ion cathode LiMn1.5Ni0.5O4 by exploiting the power of neutron reflectometry.1 Understanding the electrode/electrolyte interface is critical to developing an understanding of interfacial reactions needed to model transport phenomena and predict more stable electrolytes for electrochemical cells.2,3 However, developing the ability to control interfacial reactions in electrochemical cells is arguably one of the most critical challenges confronting researchers focused on energy storage and conversion reactions as well as liquid phase reactions such as photocatalysts and biomass conversion.2 For example, in electrochemical energy storage systems, such as batteries, the reactions between a solid electrode and a liquid electrolyte can lead to the formation of the solid electrolyte interphase (SEI), which directly mediates the stability, durability and safety of the cell. Controlling these interfacial reactions is essential to developing new, durable, and higher energy storage systems needed in the future.

  6. Direct determination of solid-electrolyte interphase thickness and composition as a function of state of charge on a silicon anode

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Veith, Gabriel M.; Doucet, Mathieu; Baldwin, J. K.; Sacci, Robert L.; Fears, Tyler M.; Wang, Yongqiang; Browning, Jim

    2015-01-01

    Using neutron reflectometry we have determined the thickness and chemistry of the solid-electrolyte interphase (SEI) layer grown on a silicon anode as a function of state of charge and during cycling. We show the chemistry of this SEI layer becomes more LiF like with increasing lithiation and more Li-C-O-F like with delithiation. More importantly the SEI layer thickness appears to increase (about 250 ) as the electrode becomes less lithiated and thins to 180 with increasing Li content (Li3.7Si). We attribute this breathing to the continual consumption of electrolyte with cycling.

  7. Direct determination of solid-electrolyte interphase thickness and composition as a function of state of charge on a silicon anode

    SciTech Connect (OSTI)

    Veith, Gabriel M.; Doucet, Mathieu; Baldwin, J. K.; Sacci, Robert L.; Fears, Tyler M.; Wang, Yongqiang; Browning, Jim

    2015-08-17

    Using neutron reflectometry we have determined the thickness and chemistry of the solid-electrolyte interphase (SEI) layer grown on a silicon anode as a function of state of charge and during cycling. We show the chemistry of this SEI layer becomes more LiF like with increasing lithiation and more Li-C-O-F like with delithiation. More importantly the SEI layer thickness appears to increase (about 250 ) as the electrode becomes less lithiated and thins to 180 with increasing Li content (Li3.7Si). We attribute this breathing to the continual consumption of electrolyte with cycling.

  8. Temperature and epi thickness dependence of the heavy ion induced latchup threshold for a CMOS/epi 16K static RAM

    SciTech Connect (OSTI)

    Smith, L.S.; Nichols, D.K.; Coss, J.R.; Price, W.E.; Binder, D.

    1987-12-01

    Data have been obtained with krypton and xenon ions for the latchup threshold vs. temperature of four different versions of a Harris CMOS/epi 16K static RAM. These special versions of the HM6516 RAM have 12-micron, 9-micron, 7-micron and 5-micron epi thicknesses, as grown. The test data showed a marked improvement in latchup resistance with decreasing epi thickness and with decreasing temperature over the range of 25/sup 0/C (operating chip ambient) to 100/sup 0/C.s.

  9. EVOLUTION OF SNOW LINE IN OPTICALLY THICK PROTOPLANETARY DISKS: EFFECTS OF WATER ICE OPACITY AND DUST GRAIN SIZE

    SciTech Connect (OSTI)

    Oka, Akinori; Nakamoto, Taishi; Ida, Shigeru, E-mail: akinorioka1@gmail.com, E-mail: nakamoto@geo.titech.ac.jp [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Tokyo (Japan)

    2011-09-10

    Evolution of a snow line in an optically thick protoplanetary disk is investigated with numerical simulations. The ice-condensing region in the disk is obtained by calculating the temperature and the density with the 1+1D approach. The snow line migrates as the mass accretion rate ( M-dot ) in the disk decreases with time. Calculations are carried out from an early phase with high disk accretion rates ( M-dot {approx}10{sup -7} M{sub sun} yr{sup -1}) to a later phase with low disk accretion rates ( M-dot {approx}10{sup -12} M{sub sun} yr{sup -1}) using the same numerical method. It is found that the snow line moves inward for M-dot {approx}>10{sup -10} M{sub sun} yr{sup -1}, while it gradually moves outward in the later evolution phase with M-dot {approx}<10{sup -10} M{sub sun} yr{sup -1}. In addition to the silicate opacity, the ice opacity is taken into consideration. In the inward migration phase, the additional ice opacity increases the distance of the snow line from the central star by a factor of 1.3 for dust grains {approx}< 10 {mu}m in size and of 1.6 for {approx}> 100 {mu}m. It is inevitable that the snow line comes inside Earth's orbit in the course of the disk evolution if the viscosity parameter {alpha} is in the range 0.001-0.1, the dust-to-gas mass ratio is higher than a tenth of the solar abundance value, and the dust grains are smaller than 1 mm. The formation of water-devoid planetesimals in the terrestrial planet region seems to be difficult throughout the disk evolution, which imposes a new challenge to planet formation theory.

  10. Thicknesses, densities, and calculated thermal resistances for loose-fill rock wool installed in two attic sections of a manufactured house

    SciTech Connect (OSTI)

    Graves, R.S.; Yarbrough, D.W.

    1986-02-01

    The effect of vibrations due to manufacturing and transport on the thickness, density, and calculated thermal resistance (R-value) of loose-fill rock wool insulation installed in two manufactured home units has been determined. Thickness and density measurements on blown attic insulation were made after installation, at the end of the manufacturing process, and after the units were towed 265 miles. These measurements were used to calculate R-values for the attic insulation. The end sections of the two units showed an overall insulation thickness decrease of about 16% and an average R-value change from 31.2 to 28.8 ft/sup 2/ x h x /sup 0/F/Btu. An estimated R-value greater than 30 ft/sup 2/ x h x /sup 0/F/Btu resulted from averaging the end and middle sections of the two units. The effect of reduced thickness along the edges of the attic space was not included in the estimate.

  11. Tunability of conduction at the LaAlO{sub 3}/SrTiO{sub 3} heterointerface: Thickness and compositional studies

    SciTech Connect (OSTI)

    Breckenfeld, E.; Bronn, N.; Mason, N.; Martin, L. W.

    2014-09-22

    The role of chemistry, film thickness, and oxygen pressure in influencing the electrical and thermal transport properties of LaAlO{sub 3}/SrTiO{sub 3} heterointerfaces is explored. Unit-cell precise growth was accomplished for films between 3 and 160 unit cells thick using reflection high-energy electron diffraction-assisted pulsed-laser deposition. Subsequent temperature-dependent studies of electrical resistivity reveal three important observations: (1) by tuning the laser fluence, we can systematically tune the interfacial conductance in a step-wise manner in this system, (2) all films exhibit a critical thickness of 34 unit cells for the onset of conduction, and (3) the nature of the conductance is highly influenced by the stoichiometry of the LaAlO{sub 3} film with La-deficient samples showing dramatic changes with thickness, while stoichiometric and La-excess films show little dependence. Time-domain thermoreflectance studies show a diminished interfacial thermal conductance for the La-deficient films when compared to La-excess and stoichiometric films, suggesting that the interfacial conductance is more influenced by extrinsic factors such as oxygen deficiency.

  12. Structural phase diagram for ultra-thin epitaxial Fe 3 O 4  / MgO(0 0 1) films: thickness and oxygen pressure dependence

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Alraddadi, S.; Hines, W.; Yilmaz, T.; Gu, G. D.; Sinkovic, B.

    2016-02-19

    A systematic investigation of the thickness and oxygen pressure dependence for the structural properties of ultra-thin epitaxial magnetite (Fe3O4) films has been carried out; for such films, the structural properties generally differ from those for the bulk when the thickness ≤10 nm. Iron oxide ultra-thin films with thicknesses varying from 3 nm to 20 nm were grown on MgO (001) substrates using molecular beam epitaxy under different oxygen pressures ranging from 1 × 10-7 torr to 1 × 10-5 torr. The crystallographic and electronic structures of the films were characterized using low energy electron diffraction (LEED) and x-ray photoemission spectroscopymore » (XPS), respectively. Moreover, the quality of the epitaxial Fe3O4 ultra-thin films was judged by magnetic measurements of the Verwey transition, along with complementary XPS spectra. We observed that under the same growth conditions the stoichiometry of ultra-thin films under 10 nm transforms from the Fe3O4 phase to the FeO phase. In this work, a phase diagram based on thickness and oxygen pressure has been constructed to explain the structural phase transformation. It was found that high-quality magnetite films with thicknesses ≤20 nm formed within a narrow range of oxygen pressure. An optimal and controlled growth process is a crucial requirement for the accurate study of the magnetic and electronic properties for ultra-thin Fe3O4 films. Furthermore, these results are significant because they may indicate a general trend in the growth of other oxide films, which has not been previously observed or considered.« less

  13. Interaction between arsenic exposure from drinking water and genetic susceptibility in carotid intima–media thickness in Bangladesh

    SciTech Connect (OSTI)

    Wu, Fen; Jasmine, Farzana; Kibriya, Muhammad G.; Liu, Mengling; Cheng, Xin; Parvez, Faruque; Paul-Brutus, Rachelle; Islam, Tariqul; Paul, Rina Rani; Sarwar, Golam; Ahmed, Alauddin; Jiang, Jieying; Islam, Tariqul; Slavkovich, Vesna; Rundek, Tatjana; Demmer, Ryan T.; Desvarieux, Moise; and others

    2014-05-01

    Epidemiologic studies that evaluated genetic susceptibility for the effects of arsenic exposure from drinking water on subclinical atherosclerosis are limited. We conducted a cross-sectional study of 1078 participants randomly selected from the Health Effects of Arsenic Longitudinal Study in Bangladesh to evaluate whether the association between arsenic exposure and carotid artery intima–media thickness (cIMT) differs by 207 single-nucleotide polymorphisms (SNPs) in 18 genes related to arsenic metabolism, oxidative stress, inflammation, and endothelial dysfunction. Although not statistically significant after correcting for multiple testing, nine SNPs in APOE, AS3MT, PNP, and TNF genes had a nominally statistically significant interaction with well-water arsenic in cIMT. For instance, the joint presence of a higher level of well-water arsenic (≥ 40.4 μg/L) and the GG genotype of AS3MT rs3740392 was associated with a difference of 40.9 μm (95% CI = 14.4, 67.5) in cIMT, much greater than the difference of cIMT associated with the genotype alone (β = − 5.1 μm, 95% CI = − 31.6, 21.3) or arsenic exposure alone (β = 7.2 μm, 95% CI = − 3.1, 17.5). The pattern and magnitude of the interactions were similar when urinary arsenic was used as the exposure variable. Additionally, the at-risk genotypes of the AS3MT SNPs were positively related to the proportion of monomethylarsonic acid (MMA) in urine, which is indicative of arsenic methylation capacity. The findings provide novel evidence that genetic variants related to arsenic metabolism may play an important role in arsenic-induced subclinical atherosclerosis. Future replication studies in diverse populations are needed to confirm the findings. - Highlights: • Nine SNPs had a nominally significant interaction with well-water arsenic in cIMT. • Three SNPs in AS3MT showed nominally significant interactions with urinary arsenic. • cIMT was much higher among subjects with higher arsenic exposure and AS3MT SNPs. • The at-risk genotypes of AS3MT SNPs were positively related to urinary MMA%.

  14. Surface Orbital 'Roughness' in Colossal Magnetoresistive Oxide...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    containing a mixed-valence of Mn3+ and Mn4+, known as manganites, represent an ideal system to address the role of the surface, because all the relevant degrees of freedom -...

  15. A Rough Road Leads To The Stars

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    then at 210 minutes before launch the flight unit was mounted into the spacecraft. The ground control unit was placed inside a temperature controlled cabinet, in which the...

  16. Thick-target neutron, gamma-ray, and radionuclide production for protons below 12 MeV on nickel and carbon beam-stops

    SciTech Connect (OSTI)

    Chadwick, M.B.; Young, P.G.; Wilson, W.B.

    1998-03-01

    Nuclear model calculations using the GNASH code are described for protons below 12 MeV incident on nickel and carbon isotopes, for beam stop design in the Los Alamos Accelerator Production of Tritium Low Energy Demonstration Accelerator (LEDA) project. The GNASH calculations apply Hauser-Feshbach and preequilibrium reaction theories and can make use of pre-calculated direct reaction cross sections to low-lying residual nucleus states. From calculated thin target cross sections, thick target 6.7 MeV and 12 MeV proton-induced production of neutrons, gamma rays, and radionuclides are determined. Emission spectra of the secondary neutrons and gamma rays are also determined. The model calculations are validated through comparisons with experimental thin- and thick-target measurements. The results of this work are being utilized as source terms in MCNP analyses for LEDA.

  17. Effects of substrate temperature and Cu underlayer thickness on the formation of SmCo{sub 5}(0001) epitaxial thin films

    SciTech Connect (OSTI)

    Ohtake, Mitsuru; Nukaga, Yuri; Futamoto, Masaaki; Kirino, Fumiyoshi

    2010-05-15

    SmCo{sub 5}(0001) epitaxial thin films were prepared on Cu(111) underlayers heteroepitaxially grown on Al{sub 2}O{sub 3}(0001) single-crystal substrates by molecular beam epitaxy. The effects of substrate temperature and Cu underlayer thickness on the crystallographic properties of SmCo{sub 5}(0001) epitaxial films were investigated. The Cu atoms of underlayer diffuse into the SmCo{sub 5} film and substitute the Co sites in SmCo{sub 5} structure forming an alloy compound of Sm(Co,Cu){sub 5}. The ordered phase formation is enhanced with increasing the substrate temperature and with increasing the Cu underlayer thickness. The Cu atom diffusion into the SmCo{sub 5} film is assisting the formation of Sm(Co,Cu){sub 5} ordered phase.

  18. Electric-Field Modulation of Curie Temperature in (Ga, Mn)As Field-Effect Transistor Structures with Varying Channel Thickness and Mn Compositions

    SciTech Connect (OSTI)

    Nishitani, Y.; Endo, M.; Chiba, D.; Matsukura, F.; Ohno, H.

    2010-01-04

    We have investigated the change of T{sub C} of ferromagnetic semiconductor (Ga, Mn)As by changing hole concentration p. The field effect transistor structure was utilized to change p. The relation T{sub C}propor top{sup 0.2} is obtained for three samples, despite the difference of their Mn composition and thickness, indicating that the relation holds over 2 decades of p.

  19. Co-electrospinning fabrication and photocatalytic performance of TiO{sub 2}/SiO{sub 2} core/sheath nanofibers with tunable sheath thickness

    SciTech Connect (OSTI)

    Cao, Houbao Du, Pingfan; Song, Lixin; Xiong, Jie Yang, Junjie; Xing, Tonghai; Liu, Xin; Wu, Rongrong; Wang, Minchao; Shao, Xiaoli

    2013-11-15

    Graphical abstract: - Highlights: The coresheath TiO{sub 2}/SiO{sub 2} nanofibers were fabricated by co-electrospinning technique. The catalytic property of nanofibers with different sheath thickness was studied. The potential methods of improving catalytic efficiency are suggested. - Abstract: In this paper, core/sheath TiO{sub 2}/SiO{sub 2} nanofibers with tunable sheath thickness were directly fabricated via a facile co-electrospinning technique with subsequent calcination at 500 C. The morphologies and structures of core/sheath TiO{sub 2}/SiO{sub 2} nanofibers were characterized by TGA, FESEM, TEM, FTIR, XPS and BET. It was found that the 1D core/sheath nanofibers are made up of anataserutile TiO{sub 2} core and amorphous SiO{sub 2} sheath. The influences of SiO{sub 2} sheath and its thickness on the photoreactivity were evaluated by observing photo-degradation of methylene blue aqueous solution under the irradiation of UV light. Compared with pure TiO{sub 2} nanofibers, the core/sheath TiO{sub 2}/SiO{sub 2} nanofibers performed a better catalytic performance. That was attributed to not only efficient separation of holeelectron pairs resulting from the formation of heterojunction but also larger surface area and surface silanol group which will be useful to provide higher capacity for oxygen adsorption to generate more hydroxyl radicals. And the optimized core/sheath TiO{sub 2}/SiO{sub 2} nanofibers with a sheath thickness of 37 nm exhibited the best photocatalytic performance.

  20. Thickness Effect of Al-Doped ZnO Window Layer on Damp Heat Stability of CuInGaSe2 Solar Cells: Preprint

    SciTech Connect (OSTI)

    Pern, F. J.; Mansfield, L.; DeHart, C.; Glick, S. H.; Yan, F.; Noufi, R.

    2011-07-01

    We investigated the damp heat (DH) stability of CuInGaSe2 (CIGS) solar cells as a function of thickness of the Al-doped ZnO (AZO) window layer from the 'standard' 0.12 μm to a modest 0.50 μm over an underlying 0.10-μm intrinsic ZnO buffer layer. The CIGS cells were prepared with external electrical contact using fine Au wire to the tiny 'standard' Ni/Al (0.05 μm/3 μm) metal grid contact pads. Bare cell coupons and sample sets encapsulated in a specially designed, Al-frame test structure with an opening for moisture ingress control using a TPT backsheet were exposed to DH at 85oC and 85% relative humidity, and characterized by current-voltage (I-V), quantum efficiency (QE), and (electrochemical) impedance spectroscopy (ECIS). The results show that bare cells exhibited rapid degradation within 50-100 h, accompanied by film wrinkling and delamination and corrosion of Mo and AlNi grid, regardless of AZO thickness. In contrast, the encapsulated cells did not show film wrinkling, delamination, and Mo corrosion after 168 h DH exposure; but the trend of efficiency degradation rate showed a weak correlation to the AZO thickness.

  1. Thickness Effect of Al-Doped ZnO Window Layer on Damp-Heat Stability of CuInGaSe2 Solar Cells

    SciTech Connect (OSTI)

    Pern, F. J.; Mansfield, L.; DeHart, C.; Glick, S. H.; Yan, F.; Noufi, R.

    2011-01-01

    We investigated the damp heat (DH) stability of CuInGaSe{sub 2} (CIGS) solar cells as a function of thickness of the Al-doped ZnO (AZO) window layer from the 'standard' 0.12 {micro}m to a modest 0.50 {micro}m over an underlying 0.10-{micro}m intrinsic ZnO buffer layer. The CIGS cells were prepared with external electrical contact using fine Au wire to the tiny 'standard' Ni/Al (0.05 {micro}m/3 {micro}m) metal grid contact pads. Bare cell coupons and sample sets encapsulated in a specially designed, Al-frame test structure with an opening for moisture ingress control using a TPT backsheet were exposed to DH at 85 C and 85% relative humidity, and characterized by current-voltage (I-V), quantum efficiency (QE), and (electrochemical) impedance spectroscopy (ECIS). The results show that bare cells exhibited rapid degradation within 50-100 h, accompanied by film wrinkling and delamination and corrosion of Mo and AlNi grid, regardless of AZO thickness. In contrast, the encapsulated cells did not show film wrinkling, delamination, and Mo corrosion after 168 h DH exposure; but the trend of efficiency degradation rate showed a weak correlation to the AZO thickness.

  2. Synthesis and characterization of 10?nm thick piezoelectric AlN films with high c-axis orientation for miniaturized nanoelectromechanical devices

    SciTech Connect (OSTI)

    Zaghloul, Usama; Piazza, Gianluca

    2014-06-23

    The scaling of piezoelectric nanoelectromechanical systems (NEMS) is challenged by the synthesis of ultrathin and high quality piezoelectric films on very thin electrodes. We report the synthesis and characterization of the thinnest piezoelectric aluminum nitride (AlN) films (10?nm) ever deposited on ultrathin platinum layers (25?nm) using reactive sputtering. X-ray diffraction, high-resolution transmission electron microscopy, and fast Fourier transform analyses confirmed the proper crystal orientation, fine columnar texture, and the continuous lattice structure within individual grains in the deposited AlN nanometer thick films. The average extracted d{sub 31} piezoelectric coefficient for the synthesized films is ?1.73 pC/N, which is comparable to the reported values for micron thick and highly c-axis oriented AlN films. The 10?nm AlN films were employed to demonstrate two different types of optimized piezoelectric nanoactuators. The unimorph actuators exhibit vertical displacements as large as 1.1??m at 0.7?V for 25??m long and 30?nm thick beams. These results have a great potential to realize miniaturized NEMS relays with extremely low voltage, high frequency resonators, and ultrasensitive sensors.

  3. TU-F-18C-02: Increasing Amorphous Selenium Thickness in Direct Conversion Flat-Panel Imagers for Contrast-Enhanced Dual-Energy Breast Imaging

    SciTech Connect (OSTI)

    Scaduto, DA; Hu, Y-H; Zhao, W

    2014-06-15

    Purpose: Contrast-enhanced (CE) breast imaging using iodinated contrast agents requires imaging with x-ray spectra at energies greater than those used in mammography. Optimizing amorphous selenium (a-Se) flat panel imagers (FPI) for this higher energy range may increase lesion conspicuity. Methods: We compare imaging performance of a conventional FPI with 200 μm a-Se conversion layer to a prototype FPI with 300 μm a-Se layer. Both detectors are evaluated in a Siemens MAMMOMAT Inspiration prototype digital breast tomosynthesis (DBT) system using low-energy (W/Rh 28 kVp) and high-energy (W/Cu 49 kVp) x-ray spectra. Detectability of iodinated lesions in dual-energy images is evaluated using an iodine contrast phantom. Effects of beam obliquity are investigated in projection and reconstructed images using different reconstruction methods. The ideal observer signal-to-noise ratio is used as a figure-of-merit to predict the optimal a-Se thickness for CE lesion detectability without compromising conventional full-field digital mammography (FFDM) and DBT performance. Results: Increasing a-Se thickness from 200 μm to 300 μm preserves imaging performance at typical mammographic energies (e.g. W/Rh 28 kVp), and improves the detective quantum efficiency (DQE) for high energy (W/Cu 49 kVp) by 30%. While the more penetrating high-energy x-ray photons increase geometric blur due to beam obliquity in the FPI with thicker a-Se layer, the effect on lesion detectability in FBP reconstructions is negligible due to the reconstruction filters employed. Ideal observer SNR for CE objects shows improvements in in-plane detectability with increasing a-Se thicknesses, though small lesion detectability begins to degrade in oblique projections for a-Se thickness above 500 μm. Conclusion: Increasing a-Se thickness in direct conversion FPI from 200 μm to 300 μm improves lesion detectability in CE breast imaging with virtually no cost to conventional FFDM and DBT. This work was partially supported by a research grant from Siemens Healthcare.

  4. Absorption enhancement through Fabry-Prot resonant modes in a 430?nm thick InGaAs/GaAsP multiple quantum wells solar cell

    SciTech Connect (OSTI)

    Behaghel, B.; Tamaki, R.; Watanabe, K.; Sodabanlu, H.; Vandamme, N.; Dupuis, C.; Bardou, N.; Cattoni, A.; Okada, Y.; Sugiyama, M.; Collin, S.; Guillemoles, J.-F.

    2015-02-23

    We study light management in a 430?nm-thick GaAs p-i-n single junction solar cell with 10 pairs of InGaAs/GaAsP multiple quantum wells (MQWs). The epitaxial layer transfer on a gold mirror improves light absorption and increases the external quantum efficiency below GaAs bandgap by a factor of four through the excitation of Fabry-Perot resonances. We show a good agreement with optical simulation and achieve around 10% conversion efficiency. We demonstrate numerically that this promising result can be further improved by anti-reflection layers. This study paves the way to very thin MQWs solar cells.

  5. STRUCTURE AND KINEMATICS OF THE STELLAR HALOS AND THICK DISKS OF THE MILKY WAY BASED ON CALIBRATION STARS FROM SLOAN DIGITAL SKY SURVEY DR7

    SciTech Connect (OSTI)

    Carollo, Daniela; Norris, John E.; Freeman, Ken C.; Beers, Timothy C.; Lee, Young Sun; Chiba, Masashi; Ivezic, Zeljko; Rockosi, Constance M.; Yanny, Brian E-mail: jen@mso.anu.edu.a E-mail: beers@pa.msu.ed E-mail: chiba@astr.tohoku.ac.j E-mail: crockosi@ucolick.or

    2010-03-20

    The structure and kinematics of the recognized stellar components of the Milky Way are explored, based on well-determined atmospheric parameters and kinematic quantities for 32360 'calibration stars' from the Sloan Digital Sky Survey (SDSS) and its first extension, SDSS-II, which included the sub-survey Sloan Extension for Galactic Understanding and Exploration (SEGUE). Full space motions for a sub-sample of 16,920 stars, exploring a local volume within 4 kpc of the Sun, are used to derive velocity ellipsoids for the inner- and outer-halo components of the Galaxy, as well as for the canonical thick-disk and proposed metal-weak thick-disk (MWTD) populations. This new sample of calibration stars represents an increase of 60% relative to the numbers used in a previous analysis. We first examine the question of whether the data require the presence of at least a two-component halo in order to account for the rotational behavior of likely halo stars in the local volume, and whether more than two components are needed. We also address the question of whether the proposed MWTD is kinematically and chemically distinct from the canonical thick disk, and point out that the Galactocentric rotational velocity inferred for the MWTD, as well as its mean metallicity, appear quite similar to the values derived previously for the Monoceros stream, suggesting a possible association between these structures. In addition, we consider the fractions of each component required to understand the nature of the observed kinematic behavior of the stellar populations of the Galaxy as a function of distance from the plane. Scale lengths and scale heights for the thick-disk and MWTD components are determined. Spatial density profiles for the inner- and outer-halo populations are inferred from a Jeans theorem analysis. The full set of calibration stars (including those outside the local volume) is used to test for the expected changes in the observed stellar metallicity distribution function with distance above the Galactic plane in situ, due to the changing contributions from the underlying stellar populations. The above issues are considered, in concert with theoretical and observational constraints from other Milky-Way-like galaxies, in light of modern cold dark matter galaxy formation models.

  6. Pull strength evaluation of Sn-Pb solder joints made to Au-Pt-Pd and Au thick film structures on low-temperature co-fired ceramic -final report for the MC4652 crypto-coded switch (W80).

    SciTech Connect (OSTI)

    Uribe, Fernando; Vianco, Paul Thomas; Zender, Gary L.

    2006-06-01

    A study was performed that examined the microstructure and mechanical properties of 63Sn-37Pb (wt.%, Sn-Pb) solder joints made to thick film layers on low-temperature co-fired (LTCC) substrates. The thick film layers were combinations of the Dupont{trademark} 4596 (Au-Pt-Pd) conductor and Dupont{trademark} 5742 (Au) conductor, the latter having been deposited between the 4596 layer and LTCC substrate. Single (1x) and triple (3x) thicknesses of the 4596 layer were evaluated. Three footprint sizes were evaluated of the 5742 thick film. The solder joints exhibited excellent solderability of both the copper (Cu) lead and thick film surface. In all test sample configurations, the 5742 thick film prevented side wall cracking of the vias. The pull strengths were in the range of 3.4-4.0 lbs, which were only slightly lower than historical values for alumina (Al{sub 2}O{sub 3}) substrates. General (qualitative) observations: (a) The pull strength was maximized when the total number of thick film layers was between two and three. Fewer that two layers did not develop as strong of a bond at the thick film/LTCC interface; more than three layers and of increased footprint area, developed higher residual stresses at the thick film/LTCC interface and in the underlying LTCC material that weakened the joint. (b) Minimizing the area of the weaker 4596/LTCC interface (e.g., larger 5742 area) improved pull strength. Specific observations: (a) In the presence of vias and the need for the 3x 4596 thick film, the preferred 4596:5742 ratio was 1.0:0.5. (b) For those LTCC components that require the 3x 4596 layer, but do not have vias, it is preferred to refrain from using the 5742 layer. (c) In the absence of vias, the highest strength was realized with a 1x thick 5742 layer, a 1x thick 4596 layer, and a footprint ratio of 1.0:1.0.

  7. Correlation between Pd metal thickness and thermally stable perpendicular magnetic anisotropy features in [Co/Pd]{sub n} multilayers at annealing temperatures up to 500 °C

    SciTech Connect (OSTI)

    An, Gwang Guk; Lee, Ja Bin; Yang, Seung Mo; Yoon, Kap Soo; Kim, Jae Hong; Chung, Woo Seong; Hong, Jin Pyo

    2015-02-15

    We examine highly stable perpendicular magnetic anisotropy (PMA) features of [Co/Pd]{sub 10} multilayers (MLs) versus Pd thickness at various ex-situ annealing temperatures. Thermally stable PMA characteristics were observed up to 500 °C, confirming the suitability of these systems for industrial applications at this temperature. Experimental observations suggest that the choice of equivalent Co and Pd layer thicknesses in a ML configuration ensures thermally stable PMA features, even at higher annealing temperatures. X-ray diffraction patterns and cross-sectional transmission electron microscopy images were obtained to determine thickness, post-annealing PMA behavior, and to explore the structural features that govern these findings.

  8. Analysis of gamma-ray spectra from foils activated in a range-thick lead target by 800-MeV protons. Final technical report

    SciTech Connect (OSTI)

    Laird, C.E.; Mullins, D.H.

    1995-06-12

    Approximately 400 gamma-ray spectra have been analyzed to obtain the types and quantities of radioisotopes produced when 800-MeV protons interact with a range-thick lead target. These spectra were obtained from the radioactive decay of product isotopes in lead disks placed at various depths and radial positions within the target. These spectra were analyzed with the computer code HYPERMET and the photopeak areas were reduced to nuclei produced per incident proton per cubic centimeter of material. Product nuclei ranged from atomic mass 160 to mass 206 and over a range of half lives from a few minutes to several weeks. The results of this analysis have been outlined in this report and transmitted on computer disk to Los Alamos National Laboratory. The consistency of these analyses have been confirmed by a comparison of photopeak areas obtained at LANL with the computer code GAMANAL with those from HYPERMET for two gamma-ray spectra. Also, the nuclear production per proton per cm{sub 3} obtained from these two spectra analyzed both at LANL and at EKU have been found to agree to within the statistical accuracy of the peak-fitting programs. This analysis of these 400 gamma-ray spectra has determined the nuclear production per incident proton per cm{sub 3} at five regularly-spaced radial positions and depths up to 40 cm into a range-thick lead target.

  9. Thickness dependent hierarchical meso/nano scale morphologies of a metal-containing block copolymer thin film induced by hybrid annealing and their pattern transfer abilities.

    SciTech Connect (OSTI)

    Ramanathan, M.; Darling, S. B.; Center for Nanoscale Materials

    2009-01-01

    In this paper we describe dewetting phenomena in organic (polystyrene, PS)/inorganic (polyferrocenyldimethylsilane, PFS) block copolymer thin films. Mesoscale dendritic structures are induced when the spin-cast thin film of this polymer is subjected to so-called hybrid annealing, which involves both thermal and solvent annealing. We show that the development and arrangement of these mesoscale dendritic structures depends on the initial film thickness in addition to the annealing time. Importantly, there are two criteria that must be fulfilled to achieve these mesoscale morphologies: (i) the film has to be subjected to hybrid annealing, i.e. either only thermal or only solvent annealing does not produce any notable mesostructures and (ii) both PS and PFS blocks must be present during the thermal and solvent annealing procedures; if one of the blocks, for instance PS, is removed before annealing then there is no mesostructure. Various possible mechanisms for the formation of these structures are discussed and results indicate that the PFS block dominates the structure formation. We also observe a ring- or worm-like nanostructure which develops only when the film is subjected to hybrid annealing at a particular film thickness. Apart from these results, here we demonstrate that mesoscale structures can be successfully transferred onto underlying substrates.

  10. Cone beam breast CT with a high pitch (75 μm), thick (500 μm) scintillator CMOS flat panel detector: Visibility of simulated microcalcifications

    SciTech Connect (OSTI)

    Shen, Youtao; Zhong, Yuncheng; Lai, Chao-Jen; Wang, Tianpeng; Shaw, Chris C.

    2013-10-15

    Purpose: To measure and investigate the improvement of microcalcification (MC) visibility in cone beam breast CT with a high pitch (75 μm), thick (500 μm) scintillator CMOS/CsI flat panel detector (Dexela 2923, Perkin Elmer).Methods: Aluminum wires and calcium carbonate grains of various sizes were embedded in a paraffin cylinder to simulate imaging of calcifications in a breast. Phantoms were imaged with a benchtop experimental cone beam CT system at various exposure levels. In addition to the Dexela detector, a high pitch (50 μm), thin (150 μm) scintillator CMOS/CsI flat panel detector (C7921CA-09, Hamamatsu Corporation, Hamamatsu City, Japan) and a widely used low pitch (194 μm), thick (600 μm) scintillator aSi/CsI flat panel detector (PaxScan 4030CB, Varian Medical Systems) were also used in scanning for comparison. The images were independently reviewed by six readers (imaging physicists). The MC visibility was quantified as the fraction of visible MCs and measured as a function of the estimated mean glandular dose (MGD) level for various MC sizes and detectors. The modulation transfer functions (MTFs) and detective quantum efficiencies (DQEs) were also measured and compared for the three detectors used.Results: The authors have demonstrated that the use of a high pitch (75 μm) CMOS detector coupled with a thick (500 μm) CsI scintillator helped make the smaller 150–160, 160–180, and 180–200 μm MC groups more visible at MGDs up to 10.8, 9, and 10.8 mGy, respectively. It also made the larger 200–212 and 212–224 μm MC groups more visible at MGDs up to 7.2 mGy. No performance improvement was observed for 224–250 μm or larger size groups. With the higher spatial resolution of the Dexela detector based system, the apparent dimensions and shapes of MCs were more accurately rendered. The results show that with the aforementioned detector, a 73% visibility could be achieved in imaging 160–180 μm MCs as compared to 28% visibility achieved by the low pitch (194 μm) aSi/CsI flat panel detector. The measurements confirm that the Hamamatsu detector has the highest MTF, followed by the Dexel detector, and then the Varian detector. However, the Dexela detector, with its thick (500 μm) CsI scintillator and low noise level, has the highest DQE at all frequencies, followed by the Varian detector, and then the Hamamatsu detector. The findings on the MC visibility correlated well with the differences in MTFs, noise power spectra, and DQEs measured for these three detectors.Conclusions: The authors have demonstrated that the use of the CMOS type Dexela detector with its high pitch (75 μm) and thick (500 μm) CsI scintillator could help improve the MC visibility. However, the improvement depended on the exposure level and the MC size. For imaging larger MCs or scanning at high exposure levels, there was little advantage in using the Dexela detector as compared to the aSi type Varian detector. These findings correlate well with the higher measured DQEs of the Dexela detector, especially at higher frequencies.

  11. Effect of thickness on the stress and magnetoelectric coupling in bilayered Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3}-CoFe{sub 2}O{sub 4} films

    SciTech Connect (OSTI)

    Wang, Jing E-mail: cwnan@tsinghua.edu.cn; Li, Zheng; Wang, Jianjun; Nan, Cewen E-mail: cwnan@tsinghua.edu.cn; He, Hongcai

    2015-01-28

    Magnetoelectric bilayered Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3}-CoFe{sub 2}O{sub 4}(PZT-CFO) films with different PZT thicknesses were grown on (111)Pt/Ti/SiO{sub 2}/Si substrates using chemical solution spin-coating. Structural characterization by X-ray diffraction and electron microscopy shows pure phases and well-defined interfaces between the PZT and CFO films. The CFO-PZT-substrate structure effectively alleviates the substrate clamping effect for the CFO layer, showing appreciable magnetoelectric responses in the composite films. Both the direct magnetoelectric effect and the magnetic field-induced Raman shifts in the A{sub 1}(TO{sub 1}) soft mode of PZT demonstrate the magnetic-mechanical-electric coupling in the films. The results also indicate that with a constant CFO layer thickness, the thickness of the PZT layer plays an important role in the stress relaxation and strong magnetoelectric coupling. The coupling could be further enhanced by increasing the CFO thickness, optimizing the volume (thickness) fraction of the PZT thickness, and releasing the clamping effect from the substrate.

  12. Plasma assisted molecular beam epitaxy growth and effect of varying buffer thickness on the formation of ultra-thin In{sub 0.17}Al{sub 0.83}N/GaN heterostructure on Si(111)

    SciTech Connect (OSTI)

    Chowdhury, Subhra; Biswas, Dhrubes

    2015-02-23

    This work reports on the detailed plasma-assisted molecular beam epitaxy (PAMBE) growth of ultra-thin In{sub 0.17}Al{sub 0.83}N/GaN heterostructures on Si(111) substrate with three different buffer thickness (600?nm, 400?nm, and 200?nm). Growth through critical optimization of growth conditions is followed by the investigation of impact of varying buffer thickness on the formation of ultra-thin 1.5?nm, In{sub 0.17}Al{sub 0.83}N1.25?nm, GaN1.5?nm, In{sub 0.17}Al{sub 0.83}N heterostructure, in terms of threading dislocation (TD) density. Analysis reveals a drastic reduction of TD density from the order 10{sup 10?}cm{sup ?2} to 10{sup 8?}cm{sup ?2} with increasing buffer thickness resulting smooth ultra-thin active region for thick buffer structure. Increasing strain with decreasing buffer thickness is studied through reciprocal space mapping analysis. Surface morphology through atomic force microscopy analysis also supports our study by observing an increase of pits and root mean square value (0.89?nm, 1.2?nm, and 1.45?nm) with decreasing buffer thickness which are resulted due to the internal strain and TDs.

  13. Method and apparatus to produce and maintain a thick, flowing, liquid lithium first wall for toroidal magnetic confinement DT fusion reactors

    DOE Patents [OSTI]

    Woolley, Robert D.

    2002-01-01

    A system for forming a thick flowing liquid metal, in this case lithium, layer on the inside wall of a toroid containing the plasma of a deuterium-tritium fusion reactor. The presence of the liquid metal layer or first wall serves to prevent neutron damage to the walls of the toroid. A poloidal current in the liquid metal layer is oriented so that it flows in the same direction as the current in a series of external magnets used to confine the plasma. This current alignment results in the liquid metal being forced against the wall of the toroid. After the liquid metal exits the toroid it is pumped to a heat extraction and power conversion device prior to being reentering the toroid.

  14. Recovery Act: Novel Kerf-Free PV Wafering that provides a low-cost approach to generate wafers from 150um to 50um in thickness

    SciTech Connect (OSTI)

    Fong, Theodore E.

    2013-05-06

    The technical paper summarizes the project work conducted in the development of Kerf-Free silicon wafering equipment for silicon solar wafering. This new PolyMax technology uses a two step process of implantation and cleaving to exfoliate 50um to 120um wafers with thicknesses ranging from 50um to 120um from a 125mm or 156mm pseudo-squared silicon ingot. No kerf is generated using this method of wafering. This method of wafering contrasts with the current method of making silicon solar wafers using the industry standard wire saw equipment. The report summarizes the activity conducted by Silicon Genesis Corporation in working to develop this technology further and to define the roadmap specifications for the first commercial proto-type equipment for high volume solar wafer manufacturing using the PolyMax technology.

  15. Elucidating hydrogen oxidation/evolution kinetics in base and acid by enhanced activities at the optimized Pt shell thickness on the Ru core

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Elbert, Katherine; Hu, Jue; Ma, Zhong; Zhang, Yu; Chen, Guangyu; An, Wei; Liu, Ping; Isaacs, Hugh S.; Adzic, Radoslav R.; Wang, Jia X.

    2015-10-05

    Hydrogen oxidation and evolution on Pt in acid are facile processes, while in alkaline electrolytes, they are 2 orders of magnitude slower. Thus, developing catalysts that are more active than Pt for these two reactions is important for advancing the performance of anion exchange membrane fuel cells and water electrolyzers. Herein, we detail a 4-fold enhancement of Pt mass activity that we achieved using single-crystalline Ru@Pt core–shell nanoparticles with two-monolayer-thick Pt shells, which doubles the activity on Pt–Ru alloy nanocatalysts. For Pt specific activity, the two- and one-monolayer-thick Pt shells exhibited enhancement factors of 3.1 and 2.3, respectively, compared tomore » the Pt nanocatalysts in base, differing considerably from the values of 1 and 0.4, respectively, in acid. To explain such behavior and the orders of magnitude difference in activity on going from acid to base, we performed kinetic analyses of polarization curves over a wide range of potential from –250 to 250 mV using the dual-pathway kinetic equation. From acid to base, the activation free energies increase the most for the Volmer reaction, resulting in a switch of the rate-determining step from the Tafel to the Volmer reaction, and a shift to a weaker optimal hydrogen binding energy. Furthermore, the much higher activation barrier for the Volmer reaction in base than in acid is ascribed to one or both of the two catalyst-insensitive factors: slower transport of OH– than H+ in water and a stronger O–H bond in water molecules (HO–H) than in hydrated protons (H2O–H+).« less

  16. Elucidating hydrogen oxidation/evolution kinetics in base and acid by enhanced activities at the optimized Pt shell thickness on the Ru core

    SciTech Connect (OSTI)

    Elbert, Katherine; Hu, Jue; Ma, Zhong; Zhang, Yu; Chen, Guangyu; An, Wei; Liu, Ping; Isaacs, Hugh S.; Adzic, Radoslav R.; Wang, Jia X.

    2015-10-05

    Hydrogen oxidation and evolution on Pt in acid are facile processes, while in alkaline electrolytes, they are 2 orders of magnitude slower. Thus, developing catalysts that are more active than Pt for these two reactions is important for advancing the performance of anion exchange membrane fuel cells and water electrolyzers. Herein, we detail a 4-fold enhancement of Pt mass activity that we achieved using single-crystalline Ru@Pt core–shell nanoparticles with two-monolayer-thick Pt shells, which doubles the activity on Pt–Ru alloy nanocatalysts. For Pt specific activity, the two- and one-monolayer-thick Pt shells exhibited enhancement factors of 3.1 and 2.3, respectively, compared to the Pt nanocatalysts in base, differing considerably from the values of 1 and 0.4, respectively, in acid. To explain such behavior and the orders of magnitude difference in activity on going from acid to base, we performed kinetic analyses of polarization curves over a wide range of potential from –250 to 250 mV using the dual-pathway kinetic equation. From acid to base, the activation free energies increase the most for the Volmer reaction, resulting in a switch of the rate-determining step from the Tafel to the Volmer reaction, and a shift to a weaker optimal hydrogen binding energy. Furthermore, the much higher activation barrier for the Volmer reaction in base than in acid is ascribed to one or both of the two catalyst-insensitive factors: slower transport of OH than H+ in water and a stronger O–H bond in water molecules (HO–H) than in hydrated protons (H2O–H+).

  17. Macro-to-microchannel transition in two-phase flow: Part 1 - Two-phase flow patterns and film thickness measurements

    SciTech Connect (OSTI)

    Ong, C.L.; Thome, J.R. [Ecole Polytechnique Federale de Lausanne, EPFL-STI-IGM-LTCM, Station 9, CH-1015 Lausanne (Switzerland)

    2011-01-15

    The classification of macroscale, mesoscale and microscale channels with respect to two-phase processes is still an open question. The main objective of this study focuses on investigating the macro-to-microscale transition during flow boiling in small scale channels of three different sizes with three different refrigerants over a range of saturation conditions to investigate the effects of channel confinement on two-phase flow patterns and liquid film stratification in a single circular horizontal channel (Part 2 covers the flow boiling heat transfer and critical heat flux). This paper presents the experimental two-phase flow pattern transition data together with a top/bottom liquid film thickness comparison for refrigerants R134a, R236fa and R245fa during flow boiling in small channels of 1.03, 2.20 and 3.04 mm diameter. Based on this work, an improved flow pattern map has been proposed by determining the flow patterns transitions existing under different conditions including the transition to macroscale slug/plug flow at a confinement number of Co {approx} 0.3-0.4. From the top/bottom liquid film thickness comparison results, it was observed that the gravity forces are fully suppressed and overcome by the surface tension and shear forces when the confinement number approaches 1, Co {approx} 1. Thus, as a new approximate rule, the lower threshold of macroscale flow is Co = 0.3-0.4 while the upper threshold of symmetric microscale flow is Co {approx} 1 with a transition (or mesoscale) region in-between. (author)

  18. EVIDENCE AGAINST AN EDGE-ON DISK AROUND THE EXTRASOLAR PLANET, 2MASS 1207 b AND A NEW THICK-CLOUD EXPLANATION FOR ITS UNDERLUMINOSITY

    SciTech Connect (OSTI)

    Skemer, Andrew J.; Close, Laird M.; Szucs, Laszlo; Apai, Daniel; Pascucci, Ilaria; Biller, Beth A.

    2011-05-10

    Since the discovery of the first directly imaged, planetary-mass object, 2MASS 1207 b, several works have sought to explain a disparity between its observed temperature and luminosity. Given its known age, distance, and spectral type, 2MASS 1207 b is underluminous by a factor of {approx}10 ({approx}2.5 mag) when compared to standard models of brown-dwarf/giant-planet evolution. In this paper, we study three possible sources of 2MASS 1207 b's underluminosity. First, we investigate Mohanty et al.'s hypothesis that a near edge-on disk, comprising large, gray-extincting grains, might be responsible for 2MASS 1207 b's underluminosity. After radiative transfer modeling, we conclude that the hypothesis is unlikely due to the lack of variability seen in multi-epoch photometry and unnecessary due to the increasing sample of underluminous brown dwarfs/giant exoplanets that cannot be explained by an edge-on disk. Next, we test the analogous possibility that a spherical shell of dust could explain 2MASS 1207 b's underluminosity. Models containing enough dust to create {approx}2.5 mag of extinction, placed at reasonable radii, are ruled out by our new Gemini/T-ReCS 8.7 {mu}m photometric upper limit for 2MASS 1207 b. Finally, we investigate the possibility that 2MASS 1207 b is intrinsically cooler than the commonly used AMES-DUSTY fits to its spectrum, and thus it is not, in fact, underluminous. New, thick-cloud model grids by Madhusudhan et al. fit 2MASS 1207 b's 1-10 {mu}m spectral energy distribution well, but they do not quite fit its near-infrared spectrum. However, we suggest that with some 'tuning', they might be capable of simultaneously reproducing 2MASS 1207 b's spectral shape and luminosity. In this case, the whole class of young, underluminous brown dwarfs/giant exoplanets might be explained by atmospheres that are able to suspend thick, dusty clouds in their photospheres at temperatures lower than field brown dwarfs.

  19. Influence of dosing sequence and film thickness on structure and resistivity of Al-ZnO films grown by atomic layer deposition

    SciTech Connect (OSTI)

    Pollock, Evan B. Lad, Robert J.

    2014-07-01

    Aluminum-doped zinc oxide (AZO) films were deposited onto amorphous silica substrates using an atomic layer deposition process with diethyl zinc (DEZ), trimethyl aluminum (TMA), and deionized water at 200?C. Three different Al doping sequences were used at a ZnO:Al ratio of 11:1 within the films. A minimum film resistivity of 1.6??10{sup ?3}?? cm was produced using sequential dosing of DEZ, TMA, DEZ, followed by H{sub 2}O for the Al doping step. This ZAZW sequence yielded an AZO film resistivity that is independent of film thickness, crystallographic texture, and grain size, as determined by high resolution x-ray diffraction (XRD). A pseudo-Voigt analysis method yields values for grain sizes that are smaller than those calculated using other XRD methods. Anisotropic grain sizes or variations in crystallographic texture have minimal influence on film resistivity, which suggests that factors other than film texture, such as intragrain scattering, may be important in influencing film resistivity.

  20. Methods and costs of thin-seam mining. Final report, 25 September 1977-24 January 1979. [Thin seam in association with a thick seam

    SciTech Connect (OSTI)

    Finch, T.E.; Fidler, E.L.

    1981-02-01

    This report defines the state of the art (circa 1978) in removing thin coal seams associated with vastly thicker seams found in the surface coal mines of the western United States. New techniques are evaluated and an innovative method and machine is proposed. Western states resource recovery regulations are addressed and representative mining operations are examined. Thin seam recovery is investigated through its effect on (1) overburden removal, (2) conventional seam extraction methods, and (3) innovative techniques. Equations and graphs are used to accommodate the variable stratigraphic positions in the mining sequence on which thin seams occur. Industrial concern and agency regulations provided the impetus for this study of total resource recovery. The results are a compendium of thin seam removal methods and costs. The work explains how the mining industry recovers thin coal seams in western surface mines where extremely thick seams naturally hold the most attention. It explains what new developments imply and where to look for new improvements and their probable adaptability.

  1. Reconstruction 3-dimensional image from 2-dimensional image of status optical coherence tomography (OCT) for analysis of changes in retinal thickness

    SciTech Connect (OSTI)

    Arinilhaq,; Widita, Rena [Department of Physics, Nuclear Physics and Biophysics Research Group, Institut Teknologi Bandung (Indonesia)

    2014-09-30

    Optical Coherence Tomography is often used in medical image acquisition to diagnose that change due easy to use and low price. Unfortunately, this type of examination produces a two-dimensional retinal image of the point of acquisition. Therefore, this study developed a method that combines and reconstruct 2-dimensional retinal images into three-dimensional images to display volumetric macular accurately. The system is built with three main stages: data acquisition, data extraction and 3-dimensional reconstruction. At data acquisition step, Optical Coherence Tomography produced six *.jpg images of each patient were further extracted with MATLAB 2010a software into six one-dimensional arrays. The six arrays are combined into a 3-dimensional matrix using a kriging interpolation method with SURFER9 resulting 3-dimensional graphics of macula. Finally, system provides three-dimensional color graphs based on the data distribution normal macula. The reconstruction system which has been designed produces three-dimensional images with size of 481 481 h (retinal thickness) pixels.

  2. Measurement of neutron spectra generated from bombardment of 4 to 24 MeV protons on a thick {sup 9}Be target and estimation of neutron yields

    SciTech Connect (OSTI)

    Paul, Sabyasachi; Sahoo, G. S.; Tripathy, S. P. E-mail: tripathy@barc.gov.in; Sunil, C.; Bandyopadhyay, T.; Sharma, S. C.; Ramjilal,; Ninawe, N. G.; Gupta, A. K.

    2014-06-15

    A systematic study on the measurement of neutron spectra emitted from the interaction of protons of various energies with a thick beryllium target has been carried out. The measurements were carried out in the forward direction (at 0 with respect to the direction of protons) using CR-39 detectors. The doses were estimated using the in-house image analyzing program autoTRAK-n, which works on the principle of luminosity variation in and around the track boundaries. A total of six different proton energies starting from 4 MeV to 24 MeV with an energy gap of 4 MeV were chosen for the study of the neutron yields and the estimation of doses. Nearly, 92% of the recoil tracks developed after chemical etching were circular in nature, but the size distributions of the recoil tracks were not found to be linearly dependent on the projectile energy. The neutron yield and dose values were found to be increasing linearly with increasing projectile energies. The response of CR-39 detector was also investigated at different beam currents at two different proton energies. A linear increase of neutron yield with beam current was observed.

  3. High quality HfO{sub 2}/p-GaSb(001) metal-oxide-semiconductor capacitors with 0.8?nm equivalent oxide thickness

    SciTech Connect (OSTI)

    Barth, Michael; Datta, Suman; Bruce Rayner, G.; McDonnell, Stephen; Wallace, Robert M.; Bennett, Brian R.; Engel-Herbert, Roman

    2014-12-01

    We investigate in-situ cleaning of GaSb surfaces and its effect on the electrical performance of p-type GaSb metal-oxide-semiconductor capacitor (MOSCAP) using a remote hydrogen plasma. Ultrathin HfO{sub 2} films grown by atomic layer deposition were used as a high permittivity gate dielectric. Compared to conventional ex-situ chemical cleaning methods, the in-situ GaSb surface treatment resulted in a drastic improvement in the impedance characteristics of the MOSCAPs, directly evidencing a much lower interface trap density and enhanced Fermi level movement efficiency. We demonstrate that by using a combination of ex-situ and in-situ surface cleaning steps, aggressively scaled HfO{sub 2}/p-GaSb MOSCAP structures with a low equivalent oxide thickness of 0.8?nm and efficient gate modulation of the surface potential are achieved, allowing to push the Fermi level far away from the valence band edge high up into the band gap of GaSb.

  4. Dependence of inverse-spin Hall effect and spin-rectified voltage on tantalum thickness in Ta/CoFeB bilayer structure

    SciTech Connect (OSTI)

    Kim, Sang-Il; Seo, Min-Su; Park, Seung-Young; Kim, Dong-Jun; Park, Byong-Guk

    2015-01-19

    Ta-layer thickness (t{sub Ta}) dependence of the measured DC voltage V from the inverse-spin Hall effect (ISHE) in Ta/CoFeB bilayer structure is experimentally investigated using the ferromagnetic resonance in the TE{sub 011} resonant cavity. The ISHE signals excluding the spin-rectified effect (SRE) were separated from the fitted curve of V against t{sub Ta}. For t{sub Ta} ≈ λ{sub Ta} (Ta-spin diffusion length = 2.7 nm), the deviation in ISHE voltage V{sub ISH} between the experimental and theoretical values is significantly increased because of the large SRE contribution, which also results in a large deviation in the spin Hall angle θ{sub SH} (from 10% to 40%). However, when t{sub Ta} ≫ λ{sub Ta}, the V{sub ISH} values are consistent with theoretical values because the SRE terms become negligible, which subsequently improves the accuracy of the obtained θ{sub SH} within 4% deviation. The results will provide an outline for an accurate estimation of the θ{sub SH} for materials with small λ value, which would be useful for utilizing the spin Hall effect in a 3-terminal spintronic devices in which magnetization can be controlled by in-plane current.

  5. Oxygen Reduction Reaction Measurements on Platinum Electrocatalysts Utilizing Rotating Disk Electrode Technique: II. Influence of Ink Formulation, Catalyst Layer Uniformity and Thickness

    SciTech Connect (OSTI)

    Shinozaki, Kazuma; Zack, Jason W.; Pylypenko, Svitlana; Pivovar, Bryan S.; Kocha, Shyam S.

    2015-09-17

    Platinum electrocatalysts supported on high surface area and Vulcan carbon blacks (Pt/HSC, Pt/V) were characterized in rotating disk electrode (RDE) setups for electrochemical area (ECA) and oxygen reduction reaction (ORR) area specific activity (SA) and mass specific activity (MA) at 0.9 V. Films fabricated using several ink formulations and film-drying techniques were characterized for a statistically significant number of independent samples. The highest quality Pt/HSC films exhibited MA 870 ± 91 mA/mgPt and SA 864 ± 56 μA/cm2 Pt while Pt/V had MA 706 ± 42 mA/mgPt and SA 1120 ± 70 μA/cm2 Pt when measured in 0.1 M HClO4, 20 mV/s, 100 kPa O2 and 23±2°C. An enhancement factor of 2.8 in themeasured SA was observable on eliminating Nafion ionomer and employing extremely thin, uniform films (~4.5 μg/cm2 Pt) of Pt/HSC. The ECA for Pt/HSC (99 ± 7 m2/gPt) and Pt/V (65 ± 5 m2/gPt) were statistically invariant and insensitive to film uniformity/thickness/fabrication technique; accordingly, enhancements in MA are wholly attributable to increases in SA. Impedance measurements coupled with scanning electron microscopy were used to de-convolute the losses within the catalyst layer and ascribed to the catalyst layer resistance, oxygen diffusion, and sulfonate anion adsorption/blocking. The ramifications of these results for proton exchange membrane fuel cells have also been examined.

  6. Oxygen Reduction Reaction Measurements on Platinum Electrocatalysts Utilizing Rotating Disk Electrode Technique: II. Influence of Ink Formulation, Catalyst Layer Uniformity and Thickness

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shinozaki, Kazuma; Zack, Jason W.; Pylypenko, Svitlana; Pivovar, Bryan S.; Kocha, Shyam S.

    2015-09-17

    Platinum electrocatalysts supported on high surface area and Vulcan carbon blacks (Pt/HSC, Pt/V) were characterized in rotating disk electrode (RDE) setups for electrochemical area (ECA) and oxygen reduction reaction (ORR) area specific activity (SA) and mass specific activity (MA) at 0.9 V. Films fabricated using several ink formulations and film-drying techniques were characterized for a statistically significant number of independent samples. The highest quality Pt/HSC films exhibited MA 870 ± 91 mA/mgPt and SA 864 ± 56 μA/cm2 Pt while Pt/V had MA 706 ± 42 mA/mgPt and SA 1120 ± 70 μA/cm2 Pt when measured in 0.1 M HClO4,more » 20 mV/s, 100 kPa O2 and 23±2°C. An enhancement factor of 2.8 in themeasured SA was observable on eliminating Nafion ionomer and employing extremely thin, uniform films (~4.5 μg/cm2 Pt) of Pt/HSC. The ECA for Pt/HSC (99 ± 7 m2/gPt) and Pt/V (65 ± 5 m2/gPt) were statistically invariant and insensitive to film uniformity/thickness/fabrication technique; accordingly, enhancements in MA are wholly attributable to increases in SA. Impedance measurements coupled with scanning electron microscopy were used to de-convolute the losses within the catalyst layer and ascribed to the catalyst layer resistance, oxygen diffusion, and sulfonate anion adsorption/blocking. The ramifications of these results for proton exchange membrane fuel cells have also been examined.« less

  7. Population studies. XIII. A new analysis of the Bidelman-Macconnell 'weak-metal' stars - confirmation of metal-poor stars in the thick disk of the galaxy

    SciTech Connect (OSTI)

    Beers, Timothy C.; Norris, John E.; Placco, Vinicius M.; Lee, Young Sun; Rossi, Silvia; Carollo, Daniela; Masseron, Thomas E-mail: jen@mso.anu.edu.au E-mail: youngsun@cnu.ac.kr E-mail: daniela.carollo@mq.edu.au

    2014-10-10

    A new set of very high signal-to-noise (S/N > 100/1), medium-resolution (R ∼ 3000) optical spectra have been obtained for 302 of the candidate 'weak-metal' stars selected by Bidelman and MacConnell. We use these data to calibrate the recently developed generalization of the Sloan Extension for Galactic Exploration and Understanding and Exploration (SEGUE) Stellar Parameter Pipeline, and obtain estimates of the atmospheric parameters (T {sub eff}, log g, and [Fe/H]) for these non-Sloan Digital Sky Survey/SEGUE data; we also obtain estimates of [C/Fe]. The new abundance measurements are shown to be consistent with available high-resolution spectroscopic determinations, and represent a substantial improvement over the accuracies obtained from the previous photometric estimates reported in Paper I of this series. The apparent offset in the photometric abundances of the giants in this sample noted by several authors is confirmed by our new spectroscopy; no such effect is found for the dwarfs. The presence of a metal-weak thick-disk (MWTD) population is clearly supported by these new abundance data. Some 25% of the stars with metallicities –1.8 < [Fe/H] ≤–0.8 exhibit orbital eccentricities e < 0.4, yet are clearly separated from members of the inner-halo population with similar metallicities by their location in a Lindblad energy versus angular momentum diagram. A comparison is made with recent results for a similar-size sample of Radial Velocity Experiment stars from Ruchti et al. We conclude, based on both of these samples, that the MWTD is real, and must be accounted for in discussions of the formation and evolution of the disk system of the Milky Way.

  8. Controlling the crystallite size and influence of the film thickness on the optical and electrical characteristics of nanocrystalline Cu{sub 2}S films

    SciTech Connect (OSTI)

    Rafea, M. Abdel; Farag, A.A.M.; Roushdy, N.

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Modification of the preparation technique in order to deposit nanostructure Cu{sub 2}S thin films. Black-Right-Pointing-Pointer Controlling the crystallite size of the prepared films. Black-Right-Pointing-Pointer Study the surface morphology, optical and electrical characteristics of Cu{sub 2}S films. -- Abstract: In this work, Cu{sub 2}S nanocrystalline films have been successfully prepared using dip-coating technique. The stoichiometry and the structural characteristics of the prepared films were characterized by energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD), respectively. The surface morphology of the deposited Cu{sub 2}S film was studied using both the scanning electron microscopy (SEM) and the atomic force microscopy (AFM). The SEM and AFM images indicate that the prepared Cu{sub 2}S films are characterized by a well-dispersed and highly dense with spherical like-shaped aggregates of size in the nano scale. The optical absorption measurements indicate that the Cu{sub 2}S nanoparticles have a direct band gap of 2.92 eV. The dispersion and absorption parameters such as the dispersion energy, oscillating energy, real and imaginary dielectric constants and dissipation factor were calculated within a wide wavelength range of the spectrum that indicates the suitability of the deposited films as solar absorber using this technique. The dark electrical resistivity ({rho}) measurements were carried out at different temperatures in the range 312-440 K. These results confirm the semiconducting characteristic of the prepared Cu{sub 2}S films. Moreover, two activation energies were obtained that indicate the presence of two dominating conduction mechanisms in these temperature ranges. The bulk electrical resistivity ({rho}{sub B}) and the mean free path (l{sub 0}) of charge carriers were estimated from the resistivity-thickness dependence. The heterojunction device of n-ZnCdS/p-Cu{sub 2}S behaves good rectifying property. The photovoltaic characteristic of the heterojunction device using the current-voltage characteristic under illumination of 100 mW/cm{sup 2} was also observed. Discussion of the obtained results and their comparison with the previous published data were also considered.

  9. Thickness dependence of magnetoelectric response for composites of Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} films on CoFe{sub 2}O{sub 4} ceramic substrates

    SciTech Connect (OSTI)

    Wang, Jing Zhu, Kongjun; Wu, Xia; Deng, Chaoyong; Peng, Renci; Wang, Jianjun

    2014-08-15

    Using chemical solution spin-coating we grew Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} films of different thicknesses on highly dense CoFe{sub 2}O{sub 4} ceramics. X-ray diffraction revealed no other phases except Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} and CoFe{sub 2}O{sub 4}. In many of these samples we observed typical ferroelectric hysteresis loops, butterfly-shaped piezoelectric strains, and the magnetic-field-dependent magnetostriction. These behaviors caused appreciable magnetoelectric responses based on magnetic-mechanical-electric coupling. Our results indicated that the thickness of the Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} film was important in obtaining strong magnetoelectric coupling.

  10. Effect of spacer layer thickness on multi-stacked InGaAs quantum dots grown on GaAs (311)B substrate for application to intermediate band solar cells

    SciTech Connect (OSTI)

    Shoji, Yasushi; Narahara, Kohei; Okada, Yoshitaka; Tanaka, Hideharu; Kita, Takashi; Akimoto, Katsuhiro

    2012-04-01

    We have investigated the properties of multi-stacked layers of self-organized In{sub 0.4}Ga{sub 0.6}As quantum dots (QDs) on GaAs (311)B grown by molecular beam epitaxy. We found that a high degree of in-plane ordering of QDs structure with a six-fold symmetry was maintained though the growth has been performed at a higher growth rate than the conventional conditions. The dependence of photoluminescence characteristics on spacer layer thickness showed an increasing degree of electronic coupling between the stacked QDs for thinner spacer layers. The external quantum efficiency for an InGaAs/GaAs quantum dot solar cell (QDSC) with a thin spacer layer thickness increased in the longer wavelength range due to additive contribution from QD layers inserted in the intrinsic region. Furthermore, a photocurrent production by 2-step photon absorption has been observed at room temperature for the InGaAs/GaAs QDSC with a spacer layer thickness of 15 nm.

  11. An analysis of the pull strength behaviors of fine-pitch, flip chip solder interconnections using a Au-Pt-Pd thick film conductor on Low-Temperature, Co-fired Ceramic (LTCC) substrates.

    SciTech Connect (OSTI)

    Uribe, Fernando R.; Kilgo, Alice C.; Grazier, John Mark; Vianco, Paul Thomas; Zender, Gary L.; Hlava, Paul Frank; Rejent, Jerome Andrew

    2008-09-01

    The assembly of the BDYE detector requires the attachment of sixteen silicon (Si) processor dice (eight on the top side; eight on the bottom side) onto a low-temperature, co-fired ceramic (LTCC) substrate using 63Sn-37Pb (wt.%, Sn-Pb) in a double-reflow soldering process (nitrogen). There are 132 solder joints per die. The bond pads were gold-platinum-palladium (71Au-26Pt-3Pd, wt.%) thick film layers fired onto the LTCC in a post-process sequence. The pull strength and failure modes provided the quality metrics for the Sn-Pb solder joints. Pull strengths were measured in both the as-fabricated condition and after exposure to thermal cycling (-55/125 C; 15 min hold times; 20 cycles). Extremely low pull strengths--referred to as the low pull strength phenomenon--were observed intermittently throughout the product build, resulting in added program costs, schedule delays, and a long-term reliability concern for the detector. There was no statistically significant correlation between the low pull strength phenomenon and (1) the LTCC 'sub-floor' lot; (2) grit blasting the LTCC surfaces prior to the post-process steps; (3) the post-process parameters; (4) the conductor pad height (thickness); (5) the dice soldering assembly sequence; or (5) the dice pull test sequence. Formation of an intermetallic compound (IMC)/LTCC interface caused by thick film consumption during either the soldering process or by solid-state IMC formation was not directly responsible for the low-strength phenomenon. Metallographic cross sections of solder joints from dice that exhibited the low pull strength behavior, revealed the presence of a reaction layer resulting from an interaction between Sn from the molten Sn-Pb and the glassy phase at the TKN/LTCC interface. The thick film porosity did not contribute, explicitly, to the occurrence of reaction layer. Rather, the process of printing the very thin conductor pads was too sensitive to minor thixotropic changes to ink, which resulted in inconsistent proportions of metal and glassy phase particles present during the subsequent firing process. The consequences were subtle, intermittent changes to the thick film microstructure that gave rise to the reaction layer and, thus, the low pull strength phenomenon. A mitigation strategy would be the use of physical vapor deposition (PVD) techniques to create thin film bond pads; this is multi-chip module, deposited (MCM-D) technology.

  12. ETA-NTP005 Electric Vehicle Rough Ride Course Test

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Electric Transportation Applications All Rights Reserved Procedure ETA-NTP005 Revision 2 ... Electric Transportation Applications All Rights Reserved Procedure ETA-NTP005 Revision 2 ...

  13. ETA-HITP05 - HICE Vehicle Rough Road Course Test

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Electric Transportation Applications All Rights Reserved i TABLE OF CONTENTS 1. ... Electric Transportation Applications All Rights Reserved 1 1. Objective The objective of ...

  14. File:Wind rough example.pdf | Open Energy Information

    Open Energy Info (EERE)

    this file. Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. If the file has been modified from...

  15. Impact of Ice Crystal Roughness on Satellite Retrieved Cloud...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    P. W. Heck 2 , R. F. Arduini 3 , R. Palikonda 3 , J. K. Ayers 3 , M. M. Khaiyer 3 , P. Yang 4 , Y. Xie 4 3 Science Systems & Applications, Inc. Hampton, VA 1 NASA Langley Research...

  16. Turbulent Flow Inside Pipes with Two-Dimensional Rib Roughness

    Energy Science and Technology Software Center (OSTI)

    1994-01-24

    A commonly used internal enhancement for single-phase forced-convective turbulent flow applications is tranverse and/or near tranverse ribs. These enhanced surfaces consist of a uniform inside diameter with periodic and discrete disruption of ribs. Enhanced tubes of this type are made by an extrusion process and are used in some condensers and evaporators in refrigeration systems. Tubes of this type fall into an enhancement category called separation and reattachment that has been identified as one ofmore » the most energy efficient. Lacking are prediction methods that are mechanistic based that can be used to calculate the heat-transfer coefficients and friction-factors for tubes with this enhancement type. This program calculates the Nusselt number and friction factor for enhanced tubes with tranverse, rectangular ribs with a spacing exceeding the reattachment length. The input quantities are the enhancement height, spacing, and the width. The Nusselt number and friction factor are calculated for a specific Reynolds number or for a range of Reynolds numbers. Users of the program are heat-exchanger designers, enhanced tubing suppliers, and research organizations or academia who are developing or validating prediction methods. The manufacturers of refrigeration heat exchangers and enhanced tube suppliers are potential users of this software.« less

  17. Enhanced Tissue Adhesion by Increased Porosity and Surface Roughness...

    Office of Scientific and Technical Information (OSTI)

    Research Org: Oak Ridge National Laboratory (ORNL) Sponsoring Org: SC USDOE - Office of Science (SC) Country of Publication: United States Language: English Word Cloud More Like ...

  18. Rough and Ready Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    National Map Retrieved from "http:en.openei.orgwindex.php?titleRoughandReadyBiomassFacility&oldid398020" Feedback Contact needs updating Image needs updating...

  19. Procedure for estimating fracture energy from fracture surface roughness

    DOE Patents [OSTI]

    Williford, Ralph E.

    1989-01-01

    The fracture energy of a material is determined by first measuring the length of a profile of a section through a fractured surface of the material taken on a plane perpendicular to the mean plane of that surface, then determining the fractal dimensionality of the surface. From this, the yield strength of the material, and the Young's Modulus of that material, the fracture energy is calculated.

  20. Hungry fungi seek rough diet, root out environmental pollutants

    SciTech Connect (OSTI)

    Bishop, J.

    1993-12-01

    The US Navy asked biochemist Stephen Aust to determine whether a common fungus could destroy 2,4,6-trinitrotoluene, a highly explosive compound popularly known as TNT. The reason white rot fungus apparently can be used to attack nearly any organic contaminant, lies in the organisms' evolution in response to a nearly infinite variety of trees and lignin. White rot fungus, evolved to degrade wood, and not every tree is the same. Environmental pollutants are very similar. Some environmental pollutants are very insoluble. Aust emphasizes that using white rot fungi in environmental treatment is not an off-the-shelf technology. Applications and remediation techniques in most cases will be site-specific success will require prior, accurate calculation of the fungi's nutrient demands, contaminant types and concentrations, local conditions, and economic considerations. Most work with white rot fungi to date has been at the laboratory scale. Experiments indicated that the fungus can indeed degrade TNT to carbon dioxide.

  1. Surface roughness effects on the solar reflectance of cool asphalt...

    Office of Scientific and Technical Information (OSTI)

    The model is then used to compute the reflectance of shingles with a mixture of different colored granules, when the reflectances of the corresponding mono-color shingles are ...

  2. The impact of monolayer coverage, barrier thickness and growth rate on the thermal stability of photoluminescence of coupled InAs/GaAs quantum dot hetero-structure with quaternary capping of InAlGaAs

    SciTech Connect (OSTI)

    Mandal, A.; Verma, U.; Halder, N.; Chakrabarti, S.

    2012-03-15

    Highlight: Black-Right-Pointing-Pointer Coupled InAs/GaAs MQDs with (In{sub 0.21}Al{sub 0.21}Ga{sub 0.58}As + GaAs) caps are considered. Black-Right-Pointing-Pointer Monolayer coverage, barrier thickness and growth rate of the dots are the factors. Black-Right-Pointing-Pointer PL peaks for the samples are within 1.1-1.3 {mu}m; significant for IBSCs and lasers. Black-Right-Pointing-Pointer NPTP (non-resonant multi-phonon assisted tunneling process) effect on FWHM of PL. -- Abstract: The self-assembled InAs/GaAs MQDs are widely investigated for their potential application in optoelectronic devices like lasers and photovoltaics. We have explored the effect of QD growth rate and structural parameters like capping layer thickness on the morphology and optical properties of the MQD heterostructures overgrown with a combination capping of InAlGaAs and GaAs. The growth rate of the seed layers in the MQD samples is also varied to investigate its effect in the vertical stacking of the islands. The change in the morphology and the optical properties of the samples due to variation in growth and structural parameters are explained by the presence of strain in the QD structures, which arises due to lattice mismatch.

  3. Cladding Attachment Over Thick Exterior Rigid Insulation

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Vertical Displacement of Furring Strip over 4" of PIC Insulation 4" Thermax- 24" OC 4" ... Vertical Displacement of Furring Strip over 4" PIC Insulation 4" Thermax- 24" OC 4" ...

  4. Thick-shell nanocrystal quantum dots

    DOE Patents [OSTI]

    Hollingsworth, Jennifer A.; Chen, Yongfen; Klimov, Victor I.; Htoon, Han; Vela, Javier

    2011-05-03

    Colloidal nanocrystal quantum dots comprising an inner core having an average diameter of at least 1.5 nm and an outer shell, where said outer shell comprises multiple monolayers, wherein at least 30% of the quantum dots have an on-time fraction of 0.80 or greater under continuous excitation conditions for a period of time of at least 10 minutes.

  5. Cladding Attachment Over Thick Exterior Sheathing

    Broader source: Energy.gov [DOE]

    This report by Building America team Building Science Corporation addresses technical questions about adding insulation to the exterior of buildings.

  6. Thick diffusion limit boundary layer test problems

    SciTech Connect (OSTI)

    Bailey, T. S.; Warsa, J. S.; Chang, J. H.; Adams, M. L.

    2013-07-01

    We develop two simple test problems that quantify the behavior of computational transport solutions in the presence of boundary layers that are not resolved by the spatial grid. In particular we study the quantitative effects of 'contamination' terms that, according to previous asymptotic analyses, may have a detrimental effect on the solutions obtained by both discontinuous finite element (DFEM) and characteristic-method (CM) spatial discretizations, at least for boundary layers caused by azimuthally asymmetric incident intensities. Few numerical results have illustrated the effects of this contamination, and none have quantified it to our knowledge. Our test problems use leading-order analytic solutions that should be equal to zero in the problem interior, which means the observed interior solution is the error introduced by the contamination terms. Results from DFEM solutions demonstrate that the contamination terms can cause error propagation into the problem interior for both orthogonal and non-orthogonal grids, and that this error is much worse for non-orthogonal grids. This behavior is consistent with the predictions of previous analyses. We conclude that these boundary layer test problems and their variants are useful tools for the study of errors that are introduced by unresolved boundary layers in diffusive transport problems. (authors)

  7. H I, CO, and Planck/IRAS dust properties in the high latitude cloud complex, MBM 53, 54, 55 and HLCG 92 – 35. Possible evidence for an optically thick H I envelope around the CO clouds

    SciTech Connect (OSTI)

    Fukui, Yasuo; Okamoto, Ryuji; Kaji, Ryohei; Yamamoto, Hiroaki; Torii, Kazufumi; Hayakawa, Takahiro; Tachihara, Kengo; Okuda, Takeshi; Ohama, Akio; Kuroda, Yutaka; Kuwahara, Toshihisa; Dickey, John M.

    2014-11-20

    We present an analysis of the H I and CO gas in conjunction with the Planck/IRAS submillimeter/far-infrared dust properties toward the most outstanding high latitude clouds MBM 53, 54, 55 and HLCG 92 – 35 at b = –30° to – 45°. The CO emission, dust opacity at 353 GHz (τ{sub 353}), and dust temperature (T {sub d}) show generally good spatial correspondence. On the other hand, the correspondence between the H I emission and the dust properties is less clear than in CO. The integrated H I intensity W{sub H} {sub I} and τ{sub 353} show a large scatter with a correlation coefficient of ∼0.6 for a T {sub d} range from 16 K to 22 K. We find, however, that W{sub H} {sub I} and τ{sub 353} show better correlation for smaller ranges of T {sub d} every 0.5 K, generally with a correlation coefficient of 0.7-0.9. We set up a hypothesis that the H I gas associated with the highest T {sub d} ≥ 21.5 K is optically thin, whereas the H I emission is generally optically thick for T {sub d} lower than 21.5 K. We have determined a relationship for the optically thin H I gas between atomic hydrogen column density and τ{sub 353}, N{sub H} {sub I} (cm{sup −2})=(1.5×10{sup 26})⋅τ{sub 353}, under the assumption that the dust properties are uniform and we have applied this to estimate N{sub H} {sub I} from τ{sub 353} for the whole cloud. N{sub H} {sub I} was then used to solve for T {sub s} and τ{sub H} {sub I} over the region. The result shows that the H I is dominated by optically thick gas having a low spin temperature of 20-40 K and a density of 40-160 cm{sup –3}. The H I envelope has a total mass of ∼1.2 × 10{sup 4} M {sub ☉}, an order of magnitude larger than that of the CO clouds. The H I envelope properties derived by this method do not rule out a mixture of H I and H{sub 2} in the dark gas, but we present indirect evidence that most of the gas mass is in the atomic state.

  8. Dependency of tunneling magneto-resistance on Fe insertion-layer thickness in Co{sub 2}Fe{sub 6}B{sub 2}/MgO-based magnetic tunneling junctions

    SciTech Connect (OSTI)

    Chae, Kyo-Suk; Park, Jea-Gun

    2015-04-21

    For Co{sub 2}Fe{sub 6}B{sub 2}/MgO-based perpendicular magnetic tunneling junctions spin valves with [Co/Pd]{sub n}-synthetic-antiferromagnetic (SyAF) layers, the tunneling-magneto-resistance (TMR) ratio strongly depends on the nanoscale Fe insertion-layer thickness (t{sub Fe}) between the Co{sub 2}Fe{sub 6}B{sub 2} pinned layer and MgO tunneling barrier. The TMR ratio rapidly increased as t{sub Fe} increased up to 0.4 nm by improving the crystalline linearity of a MgO tunneling barrier and by suppressing the diffusion of Pd atoms from a [Co/Pd]{sub n}-SyAF. However, it abruptly decreased by further increasing t{sub Fe} in transferring interfacial-perpendicular magnetic anisotropy into the IMA characteristic of the Co{sub 2}Fe{sub 6}B{sub 2} pinned layer. Thus, the TMR ratio peaked at t{sub Fe} = 0.4 nm: i.e., 120% at 29 Ωμm{sup 2}.

  9. Ground-state energy trends in single and multilayered coupled InAs/GaAs quantum dots capped with InGaAs layers: Effects of InGaAs layer thickness and annealing temperature

    SciTech Connect (OSTI)

    Shah, S.; Ghosh, K.; Jejurikar, S.; Mishra, A.; Chakrabarti, S.

    2013-08-01

    Graphical abstract: - Highlights: Investigation of ground state energy in single and multi-layered InAs/GaAs QD. Strain reducing layer (InGaAs) prevents the formation of non-radiative. Strain reducing layer (InGaAs) is responsible for high activation energy. Significant deviation from the Varshni model, E(T) = E ? ?T{sup 2}/T + ?. - Abstract: Vertically coupled, multilayered InAs/GaAs quantum dots (QDs) covered with thin InGaAs strain-reducing layers (SRLs) are in demand for various technological applications. We investigated low temperature photoluminescence of single and multilayered structures in which the SRL thickness was varied. The SRL layer was responsible for high activation energies. Deviation of experimental data from the Varshni (1967) model, E(T) = E ? ? T{sup 2}/T + ?, suggests that the InAs-layered QDs have properties different from those in bulk material. Anomalous ground-state peak linewidths (FWHM), especially for annealed multilayer structures, were observed. A ground-state peak blue-shift with a broadened linewidth was also observed. Loss of intensity was detected in samples annealed at 800 C. Presence of SRLs prevents formation of non-radiative centers under high temperature annealing. The results indicate the potential importance of such structures in optoelectronic applications.

  10. Toward the standard population synthesis model of the X-ray background: Evolution of X-ray luminosity and absorption functions of active galactic nuclei including Compton-thick populations

    SciTech Connect (OSTI)

    Ueda, Yoshihiro; Akiyama, Masayuki; Hasinger, Gnther; Miyaji, Takamitsu; Watson, Michael G.

    2014-05-10

    We present the most up to date X-ray luminosity function (XLF) and absorption function of active galactic nuclei (AGNs) over the redshift range from 0 to 5, utilizing the largest, highly complete sample ever available obtained from surveys performed with Swift/BAT, MAXI, ASCA, XMM-Newton, Chandra, and ROSAT. The combined sample, including that of the Subaru/XMM-Newton Deep Survey, consists of 4039 detections in the soft (0.5-2 keV) and/or hard (>2 keV) band. We utilize a maximum likelihood method to reproduce the count rate versus redshift distribution for each survey, by taking into account the evolution of the absorbed fraction, the contribution from Compton-thick (CTK) AGNs, and broadband spectra of AGNs, including reflection components from tori based on the luminosity- and redshift-dependent unified scheme. We find that the shape of the XLF at z ? 1-3 is significantly different from that in the local universe, for which the luminosity-dependent density evolution model gives much better description than the luminosity and density evolution model. These results establish the standard population synthesis model of the X-ray background (XRB), which well reproduces the source counts, the observed fractions of CTK AGNs, and the spectrum of the hard XRB. The number ratio of CTK AGNs to the absorbed Compton-thin (CTN) AGNs is constrained to be ?0.5-1.6 to produce the 20-50 keV XRB intensity within present uncertainties, by assuming that they follow the same evolution as CTN AGNs. The growth history of supermassive black holes is discussed based on the new AGN bolometric luminosity function.

  11. Building America Technology Solutions for New and Existing Homes:

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet) | Department of Energy Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet) Building America Technology Solutions for New and Existing Homes: Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet) This case study describes Building Science Corporation's research into spray polyurethane foams in residential roofs, performing hygrothermal

  12. Effect of the spin-twist structure on the spin-wave dynamics in Fe{sub 55}Pt{sub 45}/Ni{sub 80}Fe{sub 20} exchange coupled bi-layers with varying Ni{sub 80}Fe{sub 20} thickness

    SciTech Connect (OSTI)

    Pal, Semanti; Barman, Saswati Barman, Anjan; Hellwig, Olav

    2014-05-07

    We have investigated optically induced ultrafast magnetization dynamics of a series of Fe{sub 55}Pt{sub 45}/Ni{sub 80}Fe{sub 20} exchange spring bi-layers with varying Ni{sub 80}Fe{sub 20} thickness. Rich spin-wave spectra are observed; whose frequency shows a strong dependence on the Ni{sub 80}Fe{sub 20} layer thickness. Micromagnetic simulations based on a simplified magnetic microstructure were able to reproduce the experimental data qualitatively. The spin twist structure introduced in the Ni{sub 80}Fe{sub 20} layer gives rise to new modes in the composite system as opposed to the bare Ni{sub 80}Fe{sub 20} films.

  13. DOE Tour of Zero: The Adaptation Home by Evolutionary Home Builders...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    certification, emerald level, and Passive House ... Proper site grading carries water away from the foundation, ... below the plywood that is installed under the roof rafters. ...

  14. Draft Environmental Assessment for Direct Final Rule, 10 CFR...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Various pressed-wood products can emit formaldehyde, including particle board, plywood, pressed wood, paneling, some carpeting and backing, some furniture and dyed materials, urea-...

  15. Smooth electrode and method of fabricating same

    DOE Patents [OSTI]

    Weaver, Stanton Earl (Northville, NY); Kennerly, Stacey Joy (Albany, NY); Aimi, Marco Francesco (Niskayuna, NY)

    2012-08-14

    A smooth electrode is provided. The smooth electrode includes at least one metal layer having thickness greater than about 1 micron; wherein an average surface roughness of the smooth electrode is less than about 10 nm.

  16. ETA-HTP05 - Hybrid Electric Vehicle Rough Road Course Test

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Electric Transportation Applications All Rights Reserved i TABLE OF CONTENTS 1. ... Electric Transportation Applications All Rights Reserved 1 1. Objective The objective of ...

  17. Strain-induced reduction of surface roughness dominated spin relaxation in MOSFETs

    SciTech Connect (OSTI)

    Osintsev, Dmitri; Stanojevic, Zlatan; Baumgartner, Oskar; Sverdlov, Viktor; Selberherr, Siegfried

    2013-12-04

    Semiconductor spintronics is a rapidly developing field with large impact on microelectronics. Using spin may help to reduce power consumption and increase computational speed. Silicon is perfectly suited for spin-based applications. It is characterized by a weak spin-orbit interaction which should result in a long spin lifetime. However, recent experiments indicate the lifetime is greatly reduced in gated structures. Thus, understanding the peculiarities of the spin-orbit effects on the subband structure and details of the spin propagation in surface layers and thin silicon films is urgently needed. We investigate the contribution of the spin-orbit interaction to the equivalent valley splitting and calculate the spin relaxation matrix elements by using a perturbative k ⋅p approach. We demonstrate that applying uniaxial stress along the [110] direction may considerably suppress electron spin relaxation in silicon surface layers and thin films.

  18. Y-12's rough roads smoothed over with recycled asphalt | Y-12 National

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Security Administration historian receives 2013 Muddy Boot Award Thursday, December 19, 2013 - 3:27pm Y-12 historian Ray Smith was among the recipients at the recent East Tennessee Economic Council annual Muddy Boot Award ceremony. The Muddy Boot Award was created in the 1970s to honor individuals who have gone above the call of duty - like those who served the nation during the Manhattan Project - to make the community, the state of Tennessee and the nation a better place to live and work.

  19. Y-12's rough roads smoothed over with 23,000 tons of recycled...

    National Nuclear Security Administration (NNSA)

    Read more about it. Dec 29, 2015 at 1:00 am Blog archive April 2016 (12) March 2016 (28) February 2016 (21) January 2016 (21) December 2015 (18) November 2015 (11) October 2015 ...

  20. ANALYSIS OF HIGH FIELD NON-LINEAR LOSSES ON SRF SURFACES DUE TO SPECIFIC TOPOGRAPHIC ROUGHNESS

    SciTech Connect (OSTI)

    Chen Xu,Charles Reece,Michael Kelley

    2012-07-01

    The high-field performance of SRF cavities will eventually be limited by the realization of fundamental material limits, whether it is Hc1 or Hsh, or some derivative thereof, at which the superconductivity is lost. Before reaching this fundamental field limit at the macro level, it must be encountered at localized, perhaps microscopic, sites of field enhancement due to local topography. If such sites are small enough, they may produce thermally stabilized normal-conducting regions which contribute non-linear losses when viewed from the macro resonant field perspective, and thus produce degradation in Q0. We have undertaken a calculation of local surface magnetic field enhancement from specific fine topographic structure by conformal mapping method and numerically. A solution of the resulting normal conducting volume has been derived and the corresponding RF Ohmic loss simulated.

  1. Automatic grinding apparatus to control uniform specimen thicknesses

    DOE Patents [OSTI]

    Bryner, Joseph S.

    1982-01-01

    This invention is directed to a new and improved grinding apparatus comprising (1) a movable grinding surface, (2) a specimen holder, (3) a displacing device for moving the holder and/or grinding surface toward one another, and (4) at least three devices for limiting displacement of the holder to the grinding surface.

  2. Model-Independent Characterization of Charge Diffusion in Thick...

    Office of Scientific and Technical Information (OSTI)

    the same order as the pixel size. The only assumptions are that the charge cloud width is a monotonically increasing function of distance from the conversion point to the buried ...

  3. Origin of thickness dependence of structural phase transition...

    Office of Scientific and Technical Information (OSTI)

    Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA Materials ... Oak Ridge, Tennessee 37831, USA X-Ray Science Division, Advanced Photon Source, ...

  4. Effect of Aerosol Humidification on the Column Aerosol Optical Thickness

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Metallic fuel contaminants such as sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) may be introduced into diesel fuel through a number of different sources. As one example, biodiesel production relies on sodium hydroxide or potassium hydroxide to catalyze the reaction of vegetable oils with methanol to form methyl esters. In this process, residual amounts of Na or K can be left behind. In addition, small amounts of Ca or Mg can be added to the fuel from the purifcation process [1,2].

  5. A framework for modeling the detailed optical response of thick...

    Office of Scientific and Technical Information (OSTI)

    ; Paris U., VI-VII ; Claver, Chuck ; NOAO, Tucson ; Doherty, Peter ; Harvard U., Phys. ... Part. Phys. ; Stubbs, Christopher ; Harvard U., Phys. Dept. less Publication Date: ...

  6. Extended, Continuous Pt Nanostructures in Thick, Dispersed Electrodes...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ...ivovarnrelkickoff.pdf More Documents & Publications DOE's Fuel Cell Catalyst R&D Activities Fuel Cell Projects Kickoff Meeting PEMFC R&D at the DOE Fuel Cell Technologies Program

  7. Automatic grinding apparatus to control uniform specimen thicknesses

    DOE Patents [OSTI]

    Bryner, J.S.

    1981-01-07

    This invention is directed to a new and improved grinding apparatus comprisng: (1) a movable grinding surface; (2) a specimen holder; (3) a dislacing means for moving the holder and/or grinding surface toward one another; and (4) at least three means for limiting displacement of the holder to the grinding surface.

  8. A framework for modeling the detailed optical response of thick...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: Astrophysics,ASTRO, INST, OPTICS Word Cloud More Like This Full Text preview image File size NAView Full Text View ...

  9. Utica play, thickness map of the Point Pleasant formation

    Gasoline and Diesel Fuel Update (EIA)

  10. Utica play, thickness map of the Utica formation

    Gasoline and Diesel Fuel Update (EIA)

  11. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, L.A.

    1995-11-14

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figs.

  12. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, Lee A.

    1995-01-01

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

  13. Waterflooding a thick, heterogeneous reservoir in the Los Angeles basin

    SciTech Connect (OSTI)

    Parsons, A.R.; Lucidi, N.A.; Maloney, T.R.; Patterson, D.E. )

    1988-11-01

    The history of waterflooding the Vickers East pool is presented. The role of clean injection water in improving oil recovery, the development of an effective waterflood pattern, and the techniques used to optimize vertical coverage of water-injection wells are discussed in terms of completion, downhole equipment, and stimulation. An extensive realignment project involving an active drilling program is currently under way in the Vickers East pool.

  14. Nondestructive Evaluation of Thick Concrete Using Advanced Signal Processing Techniques

    SciTech Connect (OSTI)

    Clayton, Dwight A; Barker, Alan M; Santos-Villalobos, Hector J; Albright, Austin P; Hoegh, Kyle; Khazanovich, Lev

    2015-09-01

    The purpose of the U.S. Department of Energy Office of Nuclear Energy’s Light Water Reactor Sustainability (LWRS) Program is to develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the operating lifetimes of nuclear power plants (NPPs) beyond 60 years [1]. Since many important safety structures in an NPP are constructed of concrete, inspection techniques must be developed and tested to evaluate the internal condition. In-service containment structures generally do not allow for the destructive measures necessary to validate the accuracy of these inspection techniques. This creates a need for comparative testing of the various nondestructive evaluation (NDE) measurement techniques on concrete specimens with known material properties, voids, internal microstructure flaws, and reinforcement locations.

  15. Root region airfoil for wind turbine

    DOE Patents [OSTI]

    Tangler, James L.; Somers, Dan M.

    1995-01-01

    A thick airfoil for the root region of the blade of a wind turbine. The airfoil has a thickness in a range from 24%-26% and a Reynolds number in a range from 1,000,000 to 1,800,000. The airfoil has a maximum lift coefficient of 1.4-1.6 that has minimum sensitivity to roughness effects.

  16. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1275,,,76,106400... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1275,,"I",76,10359900,0,0,...

  17. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1273,,,74,416000... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1273,,"I",74,12907400,0,0,...

  18. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1278,,,79,214700... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1278,,"I",79,9989200,0,0,9...

  19. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1271,,,72,319500... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1271,,"I",72,12701300,0,0,...

  20. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1274,,,75,321600... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1274,,"I",75,7586100,0,0,1...

  1. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1272,,,73,335000... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1272,,"I",73,12502400,0,0,...

  2. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1277,,,78,532700... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1277,,"I",78,9702800,0,0,1...

  3. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1276,,,77,550100... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1276,,"I",77,9489600,0,0,9...

  4. Radiant Barriers | Department of Energy

    Office of Environmental Management (EM)

    points to make at least a 1.0 inch (2.5 cm) air space between it and the bottom of the roof. Foil-faced plywood or oriented strand board sheathing is also available. Note that...

  5. DOE Tour of Zero: The Vista Palm Drive by Southeast Volusia Habitat...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    single-story structure, hip-roof design, and bottom course of asphalt shingles are tar glued as well as nailed to the CDX plywood sheathing to make for a wind- and...

  6. Building America Top Innovations Hall of Fame Profile … Attic...

    Energy Savers [EERE]

    Terminology Air Barrier Material (ABM) --- A does not allow air to pass throu plywoodOSB, foam board, duc lumber. Backing --- Any material that s be sprayed so as to provide an ...

  7. NREL: Measurements and Characterization - Reflectance Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Reflectance Spectroscopy In a fraction of a second, the photovoltaic (PV) Reflectometer measures the reflectance spectrum of a wafer or cell that is dimensionally within 6 in. × 6 in. The measured reflectance plots are deconvolved to derive physical parameters including surface roughness and texture, antireflective coating thickness, metallization area and height, and backside metallization properties. Pair of drawings showing how direct normal incident light reflects in a scatter from a rough

  8. Diamonds in the rough: a strong case for the inclusion of weak-intensity X-ray diffraction data

    SciTech Connect (OSTI)

    Wang, Jimin; Wing, Richard A.

    2014-05-01

    Here, new evidence is provided to show that the inclusion of weak-intensity, high-resolution X-ray diffraction data helps to improve the quality of experimental phases by imposing proper constraints on electron-density models during noncrystallographic symmetry averaging. Overwhelming evidence exists to show that the inclusion of weak-intensity, high-resolution X-ray diffraction data helps improve the refinement of atomic models by imposing strong constraints on individual and overall temperature B factors and thus the quality of crystal structures. Some researchers consider these data to be of little value and opt to discard them during data processing, particularly at medium and low resolution, at which individual B factors of atomic models cannot be refined. Here, new evidence is provided to show that the inclusion of these data helps to improve the quality of experimental phases by imposing proper constraints on electron-density models during noncrystallographic symmetry (NCS) averaging. Using electron-density correlation coefficients as criteria, the resolution of data has successfully been extended from 3.1 to 2.5 Å resolution with redundancy-independent merging R factors from below 100% to about 310%. It is further demonstrated that phase information can be fully extracted from observed amplitudes through de novo NCS averaging. Averaging starts with uniform density inside double-shelled spherical masks and NCS matrices that are derived from bound heavy-atom clusters at the vertices of cuboctahedrally symmetric protein particles.

  9. Growth mechanism and optical properties of Ti thin films deposited onto fluorine-doped tin oxide glass substrate

    SciTech Connect (OSTI)

    Einollahzadeh-Samadi, Motahareh; Dariani, Reza S.

    2015-03-15

    In this work, a detailed study of the influence of the thickness on the morphological and optical properties of titanium (Ti) thin films deposited onto rough fluorine-doped tin oxide glass by d.c. magnetron sputtering is carried out. The films were characterized by several methods for composition, crystallinity, morphology, and optical properties. Regardless of the deposition time, all the studied Ti films of 400, 1500, 2000, and 2500?nm in thickness were single crystalline in the ?-Ti phase and also very similar to each other with respect to composition. Using the atomic force microscopy (AFM) technique, the authors analyzed the roughness evolution of the Ti films characteristics as a function of the film thickness. By applying the dynamic scaling theory to the AFM images, a steady growth roughness exponent ??=?0.72??0.02 and a dynamic growth roughness exponent ??=?0.22??0.02 were determined. The value of ? and ? are consistent with nonlinear growth model incorporating random deposition with surface diffusion. Finally, measuring the reflection spectra of the samples by a spectrophotometer in the spectral range of 3001100?nm allowed us to investigate the optical properties. The authors observed the increments of the reflection of Ti films with thickness, which by employing the effective medium approximation theory showed an increase in thickness followed by an increase in the volume fraction of metal.

  10. Root region airfoil for wind turbine

    DOE Patents [OSTI]

    Tangler, J.L.; Somers, D.M.

    1995-05-23

    A thick airfoil is described for the root region of the blade of a wind turbine. The airfoil has a thickness in a range from 24%--26% and a Reynolds number in a range from 1,000,000 to 1,800,000. The airfoil has a maximum lift coefficient of 1.4--1.6 that has minimum sensitivity to roughness effects. 3 Figs.

  11. Microcutting characteristics on the single crystal diamond tool with edge radius using molecular dynamics

    SciTech Connect (OSTI)

    Kim, Jeong-Du; Moon, Chan-Hong

    1995-12-31

    Ultraprecision metal cutting (UPMC) technology which makes possible submicrometer form accuracy and manometer roughness is developed to reach the 1nm nominal (undeformed) thickness of cut. At this thickness level, a few of atom`s layers should be considered. In this paper using the Molecuar Dynamics simulation, the phenomena of microcutting with a subnanometer chip thickness, the cutting mechanism for tool edge configuration to consider the sharp edge and round edge tool, the cut material and cutting speed are evaluated. Cutting mechanism of subnanometer depth of cut is evaluated.

  12. Improved Spatial Resolution in Thick, Fully-Depleted CCDs withEnhanced...

    Office of Scientific and Technical Information (OSTI)

    DOE Contract Number: DE-AC02-05CH11231 Resource Type: Journal Article Resource Relation: Journal Name: IEEE Transactions on Nuclear Science; Journal Volume: 2; Related Information: ...

  13. The NuSTAR View of Nearby Compton-thick Active Galactic Nuclei...

    Office of Scientific and Technical Information (OSTI)

    ; Alexander, D.M. ; Durham U. ; Ballantyne, D.R. ; Georgia Tech., Atlanta ; Bauer, F.E. ; Chile U., Catolica Space Sci. Inst., Boulder ; Boggs, S.E. ; UC, Berkeley, Space Sci. ...

  14. Measure Guideline: Incorporating Thick Layers of Exterior Rigid Insulation on Walls

    SciTech Connect (OSTI)

    Lstiburek, Joseph; Baker, Peter

    2015-04-01

    This measure guideline provides information about the design and construction of wall assemblies that use layers of rigid exterior insulation thicker than 1-½ inches and that require a secondary cladding attachment location exterior to the insulation. The guideline is separated into several distinct sections that cover: fundamental building science principles relating to the use of exterior insulation on wall assemblies; design principles for tailoring this use to the specific project goals and requirements; and construction detailing to increase understanding about implementing the various design elements.

  15. and Chandra: a Fully Compton-Thick AGN Arevalo, P.; /Chile U...

    Office of Scientific and Technical Information (OSTI)

    College Park Caltech, JPL ESA, Madrid Concepcion U. Yale Ctr. Astron. Astrophys. NASA, Goddard Astrophysics,ASTRO, GRQC Astrophysics,ASTRO, GRQC Abstract Not Provided http:...

  16. In-situ Measurement of Low-Z Material Coating Thickness on High...

    Office of Scientific and Technical Information (OSTI)

    Authors: Mueller, D 1 ; Roquemore, A L 1 ; Jaworski, M 1 ; Skinner, C H 1 ; Miller, J 1 ; Creely, A 1 ; Raman, P 2 ; Ruzic, D 2 + Show Author Affiliations PPPL ...

  17. Compression of 1-mm-thick M9763 cellular silicone foam under...

    Office of Scientific and Technical Information (OSTI)

    OSTI Identifier: 1183540 Report Number(s): LLNL-TR--667442 DOE Contract Number: ... Full Text preview image File size NAView Full Text View Full Text DOI: 10.21721183540

  18. Pump-Intensity- and Shell-Thickness-Dependent Evolution ofPhotolumine...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE SC Office of Basic Energy Sciences (SC-22) Country of Publication: United States Language: English Subject: solar (photovoltaic), solar (fuels), solid state ...

  19. Plasma sputtering robotic device for in-situ thick coatings of long, small diameter vacuum tubes

    SciTech Connect (OSTI)

    Hershcovitch, A. Blaskiewicz, M.; Brennan, J. M.; Fischer, W.; Liaw, C.-J.; Meng, W.; Todd, R.; Custer, A.; Dingus, A.; Erickson, M.; Jamshidi, N.; Laping, R.; Poole, H. J.

    2015-05-15

    A novel robotic plasma magnetron mole with a 50?cm long cathode was designed, fabricated, and operated. The reason for this endeavor is to alleviate the problems of unacceptable resistive heating of stainless steel vacuum tubes in the BNL Relativistic Heavy Ion Collider (RHIC). The magnetron mole was successfully operated to copper coat an assembly containing a full-size, stainless steel, cold bore, RHIC magnet tubing connected to two types of RHIC bellows, to which two additional pipes made of RHIC tubing were connected. To increase the cathode lifetime, a movable magnet package was developed, and the thickest possible cathode was made, with a rather challenging target to substrate (de facto anode) distance of less than 1.5?cm. Achieving reliable steady state magnetron discharges at such a short cathode to anode gap was rather challenging, when compared to commercial coating equipment, where the target to substrate distance is 10's cm; 6.3?cm is the lowest experimental target to substrate distance found in the literature. Additionally, the magnetron developed during this project provides unique omni-directional uniform coating. The magnetron is mounted on a carriage with spring loaded wheels that successfully crossed bellows and adjusted for variations in vacuum tube diameter, while keeping the magnetron centered. Electrical power and cooling water were fed through a cable bundle. The umbilical cabling system is driven by a motorized spool. Excellent coating adhesion was achieved. Measurements indicated that well-scrubbed copper coating reduced secondary electron yield to 1, i.e., the problem of electron clouds can be eliminated. Room temperature RF resistivity measurement indicated that a 10??m copper coated stainless steel RHIC tube has a conductivity close to that of pure copper tubing. Excellent coating adhesion was achieved. The device details and experimental results are described.

  20. NuSTAR Unveils a Compton-thick Type 2 Quasar in Mrk 34 (Journal...

    Office of Scientific and Technical Information (OSTI)

    Org: US DOE Office of Science (DOE SC);National Aeronautics and Space Administration (NASA) Country of Publication: United States Language: English Subject: Astrophysics,ASTRO,...

  1. Measure Guideline. Incorporating Thick Layers of Exterior Rigid Insulation on Walls

    SciTech Connect (OSTI)

    Lstiburek, Joseph; Baker, Peter

    2015-04-09

    This measure guideline, written by the U.S. Department of Energy’s Building America team Building Science Corporation, provides information about the design and construction of wall assemblies that use layers of rigid exterior insulation thicker than 1-½ in. and that require a secondary cladding attachment location exterior to the insulation. The guideline is separated into several distinct sections that cover: (1) fundamental building science principles relating to the use of exterior insulation on wall assemblies; (2) design principles for tailoring this use to the specific project goals and requirements; and (3) construction detailing to increase understanding about implementing the various design elements.

  2. Numerical simulations of optically thick accretion onto a black hole. II. Rotating flow

    SciTech Connect (OSTI)

    Fragile, P. Chris; Olejar, Ally; Anninos, Peter

    2014-11-20

    In this paper, we report on recent upgrades to our general relativistic radiation magnetohydrodynamics code, Cosmos++, including the development of a new primitive inversion scheme and a hybrid implicit-explicit solver with a more general M {sub 1} closure relation for the radiation equations. The new hybrid solver helps stabilize the treatment of the radiation source terms, while the new closure allows for a much broader range of optical depths to be considered. These changes allow us to expand by orders of magnitude the range of temperatures, opacities, and mass accretion rates, and move a step closer toward our goal of performing global simulations of radiation-pressure-dominated black hole accretion disks. In this work, we test and validate the new method against an array of problems. We also demonstrate its ability to handle super-Eddington, quasi-spherical accretion. Even with just a single proof-of-principle simulation, we already see tantalizing hints of the interesting phenomenology associated with the coupling of radiation and gas in super-Eddington accretion flows.

  3. Generalized thickness and configuration of the top of the intermediate aquifer, West-Central Florida

    SciTech Connect (OSTI)

    Corral, M.A. Jr.; Wolansky, R.M.

    1984-01-01

    The water-bearing units of the intermediate aquifer consist of discontinuous sand, gravel, shell, and limestone and dolomite beds in the Tamiami Formation of late Miocene age and the Hawthorn Formation of middle Miocene age. Within parts of Polk, Manatee, Hardee, De Soto, Sarasota, and Charlotte Counties, sand and clay beds within the Tampa Limestone that are hydraulically connected to the Hawthorn Formation are also included in the intermediate aquifer. 15 refs.

  4. Thickness-dependent coherent phonon frequency in ultrathin FeSe...

    Office of Scientific and Technical Information (OSTI)

    DOE Contract Number: AC02-76SF00515 Resource Type: Journal Article Resource Relation: Journal Name: Nano Letters; Journal Volume: 15; Journal Issue: 6 Publisher: American Chemical ...

  5. The NuSTAR View of Nearby Compton-thick Active Galactic Nuclei...

    Office of Scientific and Technical Information (OSTI)

    Dept. ; Brandt, W.N. ; Pennsylvania U. Penn State U., University Park, IGC ; Brightman, M. ; Garching, Max Planck Inst., MPE Denmark, Tech. U. ; Christensen, F.E. ; Craig, W.W. ...

  6. Utica play, thickness map of the combined Utica - Point Pleasant interval

    Gasoline and Diesel Fuel Update (EIA)

  7. Compression of 1-mm-thick M9763 cellular silicone foam under...

    Office of Scientific and Technical Information (OSTI)

    Abstract not provided. Authors: Small, W. 1 + Show Author Affiliations Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States) Publication Date: 2014-11-13 OSTI ...

  8. Improved Spatial Resolution in Thick, Fully-Depleted CCDs withEnhanced...

    Office of Scientific and Technical Information (OSTI)

    region and diffusion is controlled through the application of an external bias voltage. ... The PSF was measured at substrate bias voltages between 3 V and 115 V. At a bias voltage ...

  9. Technology Solutions Case Study: Cladding Attachment Over Thick Exterior Insulating Sheathing

    SciTech Connect (OSTI)

    2013-11-01

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of wood-framed walls and mass masonry wall assemblies. Insulation on the exterior of the structure has many direct benefits, including better effective R-value from reduced thermal bridging, better condensation resistance, reduced thermal stress on the structure, as well as other commonly associated improvements such as increased airtightness and improved water management. Although the approach has proven effective, there is resistance to its widespread implementation due to a lack of research and understanding of the mechanisms involved in the development of the vertical displacement resistance capacity. In addition, the long-term in-service performance of the system has been questioned due to potential creep effects of the assembly under the sustained dead load of the cladding and effects of varying environmental conditions. In addition, the current International Building Code (IBC) and International Residential Code (IRC) do not have a provision that specifically allows this assembly. In this project, researchers from Building Science Corporation, a Building America team, investigated these issues to better understand the mechanics behind this method of cladding attachment

  10. Thickness-dependent charge transport in few-layer MoS 2 field...

    Office of Scientific and Technical Information (OSTI)

    Authors: Lin, Ming-Wei ; Kravchenko, Ivan I. ; Fowlkes, Jason ; Li, Xufan ; Puretzky, Alexander A. ; Rouleau, Christopher M. ; Geohegan, David B. ; Xiao, Kai Publication Date: ...

  11. Bandgap Engineering of InP QDs Through Shell Thickness and Composition...

    Office of Scientific and Technical Information (OSTI)

    Subject: 36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 77 NANOSCIENCE AND NANOTECHNOLOGY; COATINGS; INDIUM PHOSPHIDES; MICROSCOPY; OXIDATION; ...

  12. Method of the cementing of material

    SciTech Connect (OSTI)

    Konovalov, Y.G.; Shutov, G.M.; Khanenya, G.P.; Dyatko, E.K.; Buben, K.K.

    1990-10-30

    Invention relates to woodworking industry and concerns method of cementing of materials of foam plastic with duralumin, glued plywood, etc. Known methods of cementing of materials by effect of electromagnetic field of superhigh frequencies are unproductive and do not make it possible to cement parts on the plane. Target of invention - acceleration of process of cementing of planar, including of complex configuration, parts and assemblies from wood, foam plastic, duralumin, glued plywood and other materials. For this material is cemented under the effect of directed electromagnetic field of superhigh frequency in the range 01-50 GHz, the specific power of 0.5-15 W/cm3.

  13. (U) Analysis of shock-initiated PBX-9501 through porous CeO2

    SciTech Connect (OSTI)

    Fredenburg, David A.; Dattelbaum, Dana Mcgraw; Dennis-Koller, Darcie

    2015-07-24

    The attenuation properties of an impact initiated PBX-9501 explosive through several thicknesses of CeO2 powder is investigated. The CeO2 is at an initial porous density of 4.0 g/cm3 , roughly 55 % of theoretical maximum density. Measurements of the input (into the powder) and propagated (through the powder) wave profiles are measured using optical velocimetry. Results show a reduction of the average wave speed, CX, and peak steady-state material velocity, uP , with increasing powder thickness from 1.5 - 5.0 mm.

  14. Rugged calorimeter with a fast rise time

    SciTech Connect (OSTI)

    McMurtry, W.M.; Dolce, S.R.

    1980-01-01

    An intrinsic 1-mil-thick gold foil calorimeter has been developed which rises to 95% of the energy deposited in less than 2 microseconds. This calorimeter is very rugged, and can withstand rough handling without damage. The time constant is long, in the millisecond range, because of its unique construction. Use of this calorimeter has produced 100% data recovery, and agreement with true deposition to less than 10%.

  15. Airfoils for wind turbine

    DOE Patents [OSTI]

    Tangler, James L.; Somers, Dan M.

    1996-01-01

    Airfoils for the blade of a wind turbine wherein each airfoil is characterized by a thickness in a range from 16%-24% and a maximum lift coefficient designed to be largely insensitive to roughness effects. The airfoils include a family of airfoils for a blade 15 to 25 meters in length, a family of airfoils for a blade 1 to 5 meters in length, and a family of airfoils for a blade 5 to 10 meters in length.

  16. Airfoils for wind turbine

    DOE Patents [OSTI]

    Tangler, J.L.; Somers, D.M.

    1996-10-08

    Airfoils are disclosed for the blade of a wind turbine wherein each airfoil is characterized by a thickness in a range from 16%-24% and a maximum lift coefficient designed to be largely insensitive to roughness effects. The airfoils include a family of airfoils for a blade 15 to 25 meters in length, a family of airfoils for a blade 1 to 5 meters in length, and a family of airfoils for a blade 5 to 10 meters in length. 10 figs.

  17. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,8,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"FUEL OIL",0,0,0,1270,,,71,0,0,0,... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1270,,"I",71,12772200,0,0,...

  18. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1269,,"I",70,13120700,0,0,...539,1,52454,"BIT","ST" 31,39,5,1,,605,1,"HAMILTON (CITY OF)","HAMILTON",1500,,0,0,0,1269,,...

  19. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,2,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"LIGHT OIL",0,0,0,1281,,,82,69000... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1281,,"I",82,0,0,0,0,0,0,0...

  20. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,2,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"LIGHT OIL",0,0,0,1279,,,80,68200... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1279,,"I",80,0,0,0,0,0,0,0...

  1. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,2,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"LIGHT OIL",0,0,0,1280,,,81,66700... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1280,,"I",81,0,0,0,0,0,0,0...

  2. CENSUS","FIPST","OWNER","PMOVER","FUELTYP","COCODE","PLTCODE...

    U.S. Energy Information Administration (EIA) Indexed Site

    ...2,1,4,2,114,24,"METROPOLITAN EDISON CO","HAMILTON",19600,"LIGHT OIL",0,0,0,1282,,,83,42000... PLYWOOD CHAMP PAPERS","HAMILTON",24500,,0,0,0,1282,,"I",83,0,0,0,0,0,0,0...

  3. DOE Zero Energy Ready Home Case Study: Promethean Homes — Gross-Shepard Residence, Charlottesville, VA

    SciTech Connect (OSTI)

    none,

    2014-09-01

    This is the first DOE Zero Energy Ready Home for this builder, who earned a Custom Builder honor in the 2014 Housing Innovation Awards. The home included rigid mineral wool board insulation over house wrap and plywood on the 2x6 advanced framed walls, achieving HERS 33 without PV.

  4. Powder-in-tube and thick-film methods of fabricating high temperature superconductors having enhanced biaxial texture

    DOE Patents [OSTI]

    Goyal, Amit; Kroeger, Donald M.

    2003-11-11

    A method for forming an electronically active biaxially textured article includes the steps of providing a substrate having a single crystal metal or metal alloy surface, deforming the substrate to form an elongated substrate surface having biaxial texture and depositing an epitaxial electronically active layer on the biaxially textured surface. The method can include at least one annealing step after the deforming step to produce the biaxially textured substrate surface. The invention can be used to form improved biaxially textured articles, such as superconducting wire and tape articles having improved J.sub.c values.

  5. Electrostatic generator/motor having rotors of varying thickness and a central stator electrically connected together into two groups

    DOE Patents [OSTI]

    Post, Richard F.

    2010-11-16

    A sub-module consists of a set of two outer sets of stationary fan-blade-shaped sectors. These outer sectors include conductive material and are maintained at ground potential in several examples. Located midway between them is a set of stationary sector plates with each plate being electrically insulated from the others. An example provides that the inner sector plates are connected together alternately, forming two groups of parallel-connected condensers that are then separately connected, through high charging circuit resistances, to a source of DC potential with respect to ground, with an additional connecting lead being provided for each group to connect their output as an AC output to a load. These same leads can he used, when connected to a driver circuit, to produce motor action.

  6. Method and apparatus for detecting the presence and thickness of carbon and oxide layers on EUV reflective surfaces

    DOE Patents [OSTI]

    Malinowski, Michael E.

    2005-01-25

    The characteristics of radiation that is reflected from carbon deposits and oxidation formations on highly reflective surfaces such as Mo/Si mirrors can be quantified and employed to detect and measure the presence of such impurities on optics. Specifically, it has been shown that carbon deposits on a Mo/Si multilayer mirror decreases the intensity of reflected HeNe laser (632.8 nm) light. In contrast, oxide layers formed on the mirror should cause an increase in HeNe power reflection. Both static measurements and real-time monitoring of carbon and oxide surface impurities on optical elements in lithography tools should be achievable.

  7. Computed and measured responses of a thick-walled hollow cylinder of salt subjected to both homogeneous and inhomogeneous loading

    SciTech Connect (OSTI)

    Morgan, H.S.; Wawersik, W.R.

    1989-06-01

    The present evaluations are based on comparisons of measurements on the hollow cylinders with predictions from three different constitutive models for rock salt. The three models are (1) an elastic power-law secondary creep (ESC) model, (2) a revision of the ESC (RESC) model with greatly reduced elastic moduli but unchanged creep parameters, and (3) a unified creep plasticity (UCP) model. The ESC model produced the predictions that differed from the Waste Isolation Pilot Plant (WIPP) in situ measurements by the factor-of-three or more. The modulus reductions in the RESC model are empirical adjustments that produced matching closures and closure rates with the WIPP measurements collected over less than five years. The UCP model yielded closures that were substantially higher than the ESC predictions but still less than the in situ measurements. At the same time, the UCP model produced closure rates in good agreement with the data. 12 refs., 5 figs., 1 tab.

  8. Nonlinear electron dynamics of gold ultrathin films induced by intense terahertz waves

    SciTech Connect (OSTI)

    Minami, Yasuo Takeda, Jun; Katayama, Ikufumi; Dao, Thang Duy; Nagao, Tadaaki; Kitajima, Masahiro

    2014-12-15

    Linear and nonlinear electron dynamics of polycrystalline gold (Au) ultrathin films with thicknesses ranging from 1.4 to 5.8?nm were investigated via transmittance terahertz (THz) spectroscopy with intense electric field transients. We prepared ultrathin films with low surface roughness formed on a Si(7??7) reconstructed surface, leading to the observation of monotonic decrease in THz transmittance with respect to film thickness. Furthermore, at all tested thicknesses, the transmittance decreased nonlinearly by 10%30% with the application if high-intensity THz electric fields. Based on a Drude-model analysis, we found a significant decrease in the damping constant induced by the THz electric field, indicating that electrons are driven beyond the polycrystalline grain boundaries in Au thin films, and consequently leading to the suppression of the electronboundary scattering rate.

  9. Quiet airfoils for small and large wind turbines

    DOE Patents [OSTI]

    Tangler, James L.; Somers, Dan L.

    2012-06-12

    Thick airfoil families with desirable aerodynamic performance with minimal airfoil induced noise. The airfoil families are suitable for a variety of wind turbine designs and are particularly well-suited for use with horizontal axis wind turbines (HAWTs) with constant or variable speed using pitch and/or stall control. In exemplary embodiments, a first family of three thick airfoils is provided for use with small wind turbines and second family of three thick airfoils is provided for use with very large machines, e.g., an airfoil defined for each of three blade radial stations or blade portions defined along the length of a blade. Each of the families is designed to provide a high maximum lift coefficient or high lift, to exhibit docile stalls, to be relatively insensitive to roughness, and to achieve a low profile drag.

  10. Spin-filtering effect of thin Al{sub 2}O{sub 3} barrier on tunneling magnetoresistance

    SciTech Connect (OSTI)

    Joo, Sungjung; Jung, K. Y.; Jun, K. I.; Shin, K. H.; Kim, D. S.; Hong, J. K.; Rhie, K. E-mail: krhie@korea.ac.kr; Lee, B. C. E-mail: krhie@korea.ac.kr

    2014-04-14

    Tunneling magnetoresistance (TMR) dependence on the Al{sub 2}O{sub 3} barrier thickness was investigated for CoFe/Al{sub 2}O{sub 3}/CoFe magnetic tunnel junctions (MTJs). MTJs with very thin Al{sub 2}O{sub 3} layers were grown by inserting an amorphous FeZr buffer layer whose role is only to reduce the roughness of bottom electrode. The TMR decreased as the thickness of the Al{sub 2}O{sub 3} layer was reduced. The results are analyzed with the dependence of the spin-filtering effect on the Al{sub 2}O{sub 3} thickness. It was found that a simple model of separating sp- and d-like electrons does not work, and it may suggest that the tunneling electrons are in rather hybridized state.

  11. Modifying mixing and instability growth through the adjustment of initial conditions in a high-energy-density counter-propagating shear experiment on OMEGA

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Merritt, E. C.; Doss, F. W.; Loomis, E. N.; Flippo, K. A.; Kline, J. L.

    2015-06-24

    Counter-propagating shear experiments conducted at the OMEGA Laser Facility have been evaluating the effect of target initial conditions, specifically the characteristics of a tracer foil located at the shear boundary, on Kelvin-Helmholtz instability evolution and experiment transition toward nonlinearity and turbulence in the high-energy-density (HED) regime. Experiments are focused on both identifying and uncoupling the dependence of the model initial turbulent length scale in variable-density turbulence models of k-ϵ type on competing physical instability seed lengths as well as developing a path toward fully developed turbulent HED experiments. We present results from a series of experiments controllably and independently varyingmore » two initial types of scale lengths in the experiment: the thickness and surface roughness (surface perturbation scale spectrum) of a tracer layer at the shear interface. We show that decreasing the layer thickness and increasing the surface roughness both have the ability to increase the relative mixing in the system, and thus theoretically decrease the time required to begin transitioning to turbulence in the system. In addition, we also show that we can connect a change in observed mix width growth due to increased foil surface roughness to an analytically predicted change in model initial turbulent scale lengths.« less

  12. Surface Quality of Ti-6%Al-4%V ELI When Machined Using CVD-Carbide Tools at High Cutting Speed

    SciTech Connect (OSTI)

    Gusri, A. I.; Che Hassan, C. H.; Jaharah, A. G.; Yasir, A.; Zaid, Y.; Yanuar, B.

    2011-01-17

    Machining of Ti-6Al-4V ELI becomes more interested topic due to extremely weight-to-strength ratio and resistance to corrosion at elevated temperature. Quality of machined surface is presented by surface roughness, surface texture and damages of microstructure of titanium alloys. The turning parameters evaluated are cutting speed of 55-95 m/min, feed rate of 0.15-0.35 mm/rev, depth of cut of 0.10-0.20 mm and tool grade of CVD carbide tools. The results show the trend lines of surface roughness value are higher at the initial machining and the surface texture profile has a strong correlation with the feed rate. At the machining condition of cutting speed of 95 m/min, feed rate of 0.35 mm/rev and depth of cut of 0.10 mm produced the with layer with thickness of 2.0 {mu}m.

  13. Test plan/procedure for the SPM-1 shipping container system. Revision 0

    SciTech Connect (OSTI)

    Flanagan, B.D.

    1995-07-01

    The 49 CFR 173.465 Type A packaging tests will verify that SPM-1 will provide adequate protection and pass as a Type A package. Test will determine that the handle of the Pig will not penetrate through the plywood spacer and rupture the shipping container. Test plan/procedure provides planning, pre-test, setup, testing, and post-testing guidelines and procedures for conducting the {open_quotes}Free Drop Test{close_quotes} procedure for the SPM-1 package.

  14. Rough order of magnitude cost estimate for immobilization of 18.2 MT of plutonium using existing facilities at the Savannah River site: alternatives 3A/5A/6A/6B/7A/9A

    SciTech Connect (OSTI)

    DiSabatino, A., LLNL

    1998-06-01

    The purpose of this Cost Estimate Report is to identify preliminary capital and operating costs for a facility to immobilize 18.2 metric tons (nominal) of plutonium using ceramic in a new facility at Savannah River Site (SRS).

  15. Comment on A study of vertical and in-plane electron mobility due to interface roughness scattering at low temperature in InAs-GaSb superlattices [J. Appl. Phys. 114, 053712 (2013)

    SciTech Connect (OSTI)

    Szmulowicz, F.

    2014-04-14

    The purpose of this comment is to point out that the paper by Safa, Asgari, and Faraone [J. Appl. Phys. 114, 053712 (2013)] (SAF) on electronic transport in superlattices contains a number of errors in physics and execution. By dealing with a finite number of periods and forcing the wave function to be zero at the upper and lower boundaries of the superlattice stack, SAF have turned the system into a quantum well for which the momentum along the growth axis is not a good quantum number, so that the bands in the growth direction are flat and the corresponding carrier velocities and vertical mobilities are zero. A number of other errors allow the authors to get nonzero results and to reach conclusions that qualitatively mirror those of Szmulowicz, Haugan, Elhamri, and Brown [Phys. Rev. B 84, 155307 (2011)].

  16. THE DARK ENERGY SURVEY: PROSPECTS FOR RESOLVED STELLAR POPULATIONS

    SciTech Connect (OSTI)

    Rossetto, Bruno M.; Santiago, Baslio X.; Girardi, Lo; Camargo, Julio I. B.; Balbinot, Eduardo; da Costa, Luiz N.; Yanny, Brian; Maia, Marcio A. G.; Makler, Martin; Ogando, Ricardo L. C.; Pellegrini, Paulo S.; Ramos, Beatriz; de Simoni, Fernando; Armstrong, R.; Bertin, E.; Desai, S.; Kuropatkin, N.; Lin, H.; Mohr, J. J.; Tucker, D. L.

    2011-06-01

    Wide angle and deep surveys, regardless of their primary purpose, always sample a large number of stars in the Galaxy and in its satellite system. We here make a forecast of the expected stellar sample resulting from the Dark Energy Survey and the perspectives that it will open for studies of Galactic structure and resolved stellar populations in general. An estimated 1.2 x 108 stars will be sampled in DES grizY filters in the southern equatorial hemisphere. This roughly corresponds to 20% of all DES sources. Most of these stars belong to the stellar thick disk and halo of the Galaxy.

  17. THE DARK ENERGY SURVEY: PROSPECTS FOR RESOLVED STELLAR POPULATIONS

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rossetto, Bruno M.; Santiago, Baslio X.; Girardi, Lo; Camargo, Julio I. B.; Balbinot, Eduardo; da Costa, Luiz N.; Yanny, Brian; Maia, Marcio A. G.; Makler, Martin; Ogando, Ricardo L. C.; et al

    2011-06-01

    Wide angle and deep surveys, regardless of their primary purpose, always sample a large number of stars in the Galaxy and in its satellite system. We here make a forecast of the expected stellar sample resulting from the Dark Energy Survey and the perspectives that it will open for studies of Galactic structure and resolved stellar populations in general. An estimated 1.2 x 108 stars will be sampled in DES grizY filters in the southern equatorial hemisphere. This roughly corresponds to 20% of all DES sources. Most of these stars belong to the stellar thick disk and halo of themoreGalaxy.less

  18. Getting a better measure of spin with diamond | Jefferson Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Getting a better measure of spin with diamond Diamond detector The Hall C Compton Polarimeter uses a novel detector system built of thin slivers of diamond, seen here. The lab-grown slices of diamond, measuring roughly three-quarters of an inch square (2 cm) and a mere two hundredths of an inch thick, are outfitted like computer chips, with 96 tiny electrodes stuck to them. The electrodes send a signal when the diamond detector counts an electron. Getting a better measure of spin with diamond

  19. Light Trapping for Thin Silicon Solar Cells by Femtosecond Laser Texturing: Preprint

    SciTech Connect (OSTI)

    Lee, B. G.; Lin, Y. T.; Sher, M. J.; Mazur, E.; Branz, H. M.

    2012-06-01

    Femtosecond laser texturing is used to create nano- to micron-scale surface roughness that strongly enhances light-trapping in thin crystalline silicon solar cells. Light trapping is crucial for thin solar cells where a single light-pass through the absorber is insufficient to capture the weakly absorbed red and near-infrared photons, especially with an indirect-gap semiconductor absorber layer such as crystalline Si which is less than 20 um thick. We achieve enhancement of the optical absorption from light-trapping that approaches the Yablonovitch limit.

  20. Induced spin-polarization of EuS at room temperature in Ni/EuS multilayers

    SciTech Connect (OSTI)

    Poulopoulos, P.; Goschew, A.; Straub, A.; Fumagalli, P.; Kapaklis, V.; Wolff, M.; Delimitis, A.; Wilhelm, F.; Rogalev, A.; Pappas, S. D.

    2014-03-17

    Ni/EuS multilayers with excellent multilayer sequencing are deposited via e-beam evaporation on the native oxide of Si(100) wafers at 4 × 10{sup −9} millibars. The samples have very small surface and interface roughness and show sharp interfaces. Ni layers are nanocrystalline 4–8 nm thick and EuS layers are 2–4 nm thick and are either amorphous or nanocrystalline. Unlike for Co/EuS multilayers, all Eu ions are in divalent (ferromagnetic) state. We show a direct antiferromagnetic coupling between EuS and Ni layers. At room temperature, the EuS layers are spin-polarized due to the proximity of Ni. Therefore, Ni/EuS is a candidate for room-temperature spintronics applications.

  1. Design and experimental results for the S814 airfoil

    SciTech Connect (OSTI)

    Somers, D.M. [Airfoils, Inc., State College, PA (United States)

    1997-01-01

    A 24-percent-thick airfoil, the S814, for the root region of a horizontal-axis wind-turbine blade has been designed and analyzed theoretically and verified experimentally in the low-turbulence wind tunnel of the Delft University of Technology Low Speed Laboratory, The Netherlands. The two primary objectives of high maximum lift, insensitive to roughness, and low profile drag have been achieved. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results show good agreement with the exception of maximum lift which is overpredicted. Comparisons with other airfoils illustrate the higher maximum lift and the lower profile drag of the S814 airfoil, thus confirming the achievement of the objectives.

  2. Sputtering of cobalt film with perpendicular magnetic anisotropy on disorder-free graphene

    SciTech Connect (OSTI)

    Jamali, Mahdi; Lv, Yang; Zhao, Zhengyang; Wang, Jian-Ping

    2014-10-15

    Growth of thin cobalt film with perpendicular magnetic anisotropy has been investigated on pristine graphene for spin logic and memory applications. By reduction of the kinetic energy of the sputtered atoms using indirect sputtered deposition, deposition induced defects in the graphene layer have been controlled. Cobalt film on graphene with perpendicular magnetic anisotropy has been developed. Raman spectroscopy of the graphene surface shows very little disorder induced in the graphene by the sputtering process. In addition, upon increasing the cobalt film thickness, the disorder density increases on the graphene and saturates for thicknesses of Co layers above 1 nm. The AFM image indicates a surface roughness of about 0.86 nm. In addition, the deposited film forms a granular structure with a grain size of about 40 nm.

  3. Methodology for the neutron time of flight measurement of 120-GeV proton-induced reactions on a thick copper target

    SciTech Connect (OSTI)

    Sanami, T.; Iwamoto, Y.; Kajimoto, T.; Shigyo, N.; Hagiwara, M.; Lee, H. S.; Ramberg, E.; Coleman, R.; Soha, A.; Jensen, D.; Leveling, A.; Mokhov, N. V.; Boehnlein, D.; Vaziri, K.; Ishibashi, K.; Sakamoto, Y.; Nakashima, H.

    2011-12-06

    Our methodology for the time-of-flight measurement of the neutron energy spectrum for a high-energy proton-beam-induced reaction was established at the Fermilab Test Beam Facility of the Fermi National Accelerator Laboratory. The 120-GeV proton beam with 3 × 105 protons/spill was prepared for event-by-event counting of incident protons and emitted neutrons for time-of-flight energy determination. An NE213 organic liquid scintillator (12.7 cm in diameter by 12.7 cm in length) was employed with a veto plastic scintillator and a pulse-shape discrimination technique to identify neutrons. Raw waveforms of NE213, veto and beam detectors were recorded to discriminate the effects of multi-proton beam events by considering different time windows. The neutron energy spectrum ranging from 10 to 800 MeV was obtained for a 60-cm-long copper target at 90° with respect to the beam axis. Finally our obtained spectrum was consistent with that deduced employing the conventional unfolding technique as well as that obtained in a 40-GeV/c thin-target experiment.

  4. Development of automated welding process for field fabrication of thick walled pressure vessels. Technical progress report, second quarter, FY 1980, ending March 28, 1980

    SciTech Connect (OSTI)

    Schneider, U.A.

    1980-01-01

    Progress on a metallurgical contract is reported: (1) specifications of 2 1/4 chromium-1 molybdenum low alloy steel plate for a coal gasification project; (2) methods of welding and analyses of helium-argon mixtures for welding; and (3) tensile properties of welded joints. (LTN)

  5. EFFECT OF PHOTODESORPTION ON THE SNOW LINES AT THE SURFACE OF OPTICALLY THICK CIRCUMSTELLAR DISKS AROUND HERBIG Ae/Be STARS

    SciTech Connect (OSTI)

    Oka, Akinori; Nakamoto, Taishi [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Ookayama, Meguro, Tokyo 152-8551 (Japan); Inoue, Akio K. [College of General Education, Osaka Sangyo University, 3-1-1, Nakagaito, Daito, Osaka 574-8530 (Japan); Honda, Mitsuhiko, E-mail: akinoue@las.osaka-sandai.ac.jp [Department of Information Science, Kanagawa University, 2946, Tsuchiya, Hiratsuka, Kanagawa 259-1293 (Japan)

    2012-03-10

    We investigate the effect of photodesorption on the snow line position at the surface of a protoplanetary disk around a Herbig Ae/Be star, motivated by the detection of water ice particles at the surface of the disk around HD142527 by Honda et al. For this aim, we obtain the density and temperature structure in the disk with a 1+1D radiative transfer and determine the distribution of water ice particles in the disk by the balance between condensation, sublimation, and photodesorption. We find that photodesorption induced by far-ultraviolet radiation from the central star depresses the ice-condensation front toward the mid-plane and pushes the surface snow line significantly outward when the stellar effective temperature exceeds a certain critical value. This critical effective temperature depends on the stellar luminosity and mass, the water abundance in the disk, and the yield of photodesorption. We present an approximate analytic formula for the critical temperature. We separate Herbig Ae/Be stars into two groups on the HR diagram according to the critical temperature: one is the disks where photodesorption is effective and from which we may not find ice particles at the surface, and the other is the disks where photodesorption is not effective. We estimate the snow line position at the surface of the disk around HD142527 to be 100-300 AU, which is consistent with the water ice detection at >140 AU in the disk. All the results depend on the dust grain size in a complex way, and this point requires more work in the future.

  6. Improvements in 500-kHz Ultrasonic Phased-Array Probe Designs for Evaluation of Thick Section Cast Austenitic Stainless Steel Piping Welds

    SciTech Connect (OSTI)

    Crawford, Susan L.; Cinson, Anthony D.; Moran, Traci L.; Anderson, Michael T.; Diaz, Aaron A.

    2011-02-01

    PNNL has been studying and performing confirmatory research on the inspection of piping welds in coarse-grained steels for over 30 years. More recent efforts have been the application of low frequency phased array technology to this difficult to inspect material. The evolution of 500 kHz PA probes and the associated electronics and scanning protocol are documented in this report. The basis for the probe comparisons are responses from one mechanical fatigue crack and two thermal fatigue cracks in large-bore cast mockup specimens on loan from the Electric Power Research Institution. One of the most significant improvements was seen in the use of piezo-composite elements in the later two probes instead of the piezo-ceramic material used in the prototype array. This allowed a reduction in system gain of 30 dB and greatly reduced electronic noise. The latest probe had as much as a 5 dB increase in signal to noise, adding to its flaw discrimination capability. The system electronics for the latest probe were fully optimized for a 500 kHz center frequency, however significant improvements were not observed in the center frequency of the flaw responses. With improved scanner capabilities, smaller step sizes were used, allowing both line and raster data improvements to be made with the latest probe. The small step sizes produce high resolution images that improve flaw discrimination and, along with the increased signal-to-noise ratio inherent in the latest probe design, enhanced detection of the upper regions of the flaw make depth sizing more plausible. Finally, the physical sizes of the probes were progressively decreased allowing better access to the area of interest on specimens with weld crowns, and the latest probe was designed with non-integral wedges providing flexibility in focusing on different specimen geometries.

  7. Cladding Attachment Over Thick Exterior Insulating Sheathing (Fact Sheet), Building America Case Study: Technology Solutions for New and Existing Homes, Building Technologies Office (BTO)

    Energy Savers [EERE]

    Department of Energy Civilian Radioactive Waste Management System Requirements Document Civilian Radioactive Waste Management System Requirements Document This document specifies the top-level requirements for the Civilian Radioactive Waste Management System (CRWMS). The document is referred to herein as the CRD, for CRWMS Requirements Document. PDF icon Civilian Radioactive Waste Management System Requirements Document More Documents & Publications FY 2007 Total System Life Cycle Cost,

  8. Theoretical Analysis of Effects of Deep Level, Back Contact, and Absorber Thickness on Capacitance-Voltage Profiling of CdTe Thin-Film Solar Cells

    SciTech Connect (OSTI)

    Li, J. V.; Halverson, A. F.; Sulima, O. V.; Bansal, S.; Burst, J. M.; Barnes, T. M.; Gessert, T. A.; Levi, D. H.

    2012-05-01

    The apparent carrier density profile measured by the capacitance-voltage technique in CdTe thin-film solar cells frequently displays a distinctive U-shape. We show that, even assuming a uniform carrier density, such a U-shape may arise from deep levels, a non-ohmic back-contact, and a thin absorber, which are commonly present in practical CdTe thin-film solar cells. A thin CdTe absorber contributes to the right branch of the U-shape due to a punch-through effect at reverse or zero biases, when the CdTe absorber is nearly fully depleted. A rectifying back-contact contributes to both branches of the U-shape due to voltage sharing with the front junction under a forward bias and early punch-through under a reverse bias. Deep levels contribute to the right branch, but also raise the bottom of the U-shape, leading to an overestimate of carrier density.

  9. Methodology for the neutron time of flight measurement of 120-GeV proton-induced reactions on a thick copper target

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sanami, T.; Iwamoto, Y.; Kajimoto, T.; Shigyo, N.; Hagiwara, M.; Lee, H. S.; Ramberg, E.; Coleman, R.; Soha, A.; Jensen, D.; et al

    2011-12-06

    Our methodology for the time-of-flight measurement of the neutron energy spectrum for a high-energy proton-beam-induced reaction was established at the Fermilab Test Beam Facility of the Fermi National Accelerator Laboratory. The 120-GeV proton beam with 3 × 105 protons/spill was prepared for event-by-event counting of incident protons and emitted neutrons for time-of-flight energy determination. An NE213 organic liquid scintillator (12.7 cm in diameter by 12.7 cm in length) was employed with a veto plastic scintillator and a pulse-shape discrimination technique to identify neutrons. Raw waveforms of NE213, veto and beam detectors were recorded to discriminate the effects of multi-proton beammore » events by considering different time windows. The neutron energy spectrum ranging from 10 to 800 MeV was obtained for a 60-cm-long copper target at 90° with respect to the beam axis. Finally our obtained spectrum was consistent with that deduced employing the conventional unfolding technique as well as that obtained in a 40-GeV/c thin-target experiment.« less

  10. Electrodeposition, characterization and morphological investigations of NiFe/Cu multilayers prepared by pulsed galvanostatic, dual bath technique

    SciTech Connect (OSTI)

    Esmaili, S.; Bahrololoom, M.E.; Kavanagh, K.L.

    2011-02-15

    NiFe/Cu multilayers were grown sequentially by pulsed electrodeposition on copper (Cu) substrates. The layers were prepared in galvanostatic mode using a dual bath technique. The morphology, thickness, roughness and composition of the layers were studied using scanning electron microscopy, scanning transmission electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffraction and atomic force microscopy. Analysis showed that the resulting multilayers were continuous layers with a root mean square roughness of 30 nm and a grain size of 20-60 nm. The Cu substrate and the electrodeposited Cu layer were preferentially (200) oriented while the NiFe layers were polycrystalline but with a preferred (200) texture. The thinnest multilayers produced were 20/40, NiFe/Cu, respectively. - Research Highlights: {yields} Thin MLs of Cu and Py can be ED utilizing a pulsed-galvanostatic, DBT. {yields} The resulting multilayers were continuous layers with an rms of 30 nm. {yields} The smallest average thickness achieved by DBT was 40 nm/20 nm for Cu/NiFe.

  11. Microstructure, Processing, Performance Relationships for High Temperature Coatings

    SciTech Connect (OSTI)

    Thomas M. Lillo

    2011-04-01

    This work evaluates the suitability of iron aluminide coatings for use in high temperature fossil fuel combustion environments, such as boiler applications. The coatings are applied using High Velocity Oxy-Fuel (HVOF) thermal spray techniques. Iron aluminide coatings, with the nominal composition of Fe3Al, were applied to various high temperature structural materials (316 Stainless Steel, 9Cr-1Mo steel and Inconel 600) that typically lack inherent resistance to environmental degradation found in fossil fuel combustion atmospheres. Coating/substrate combinations were subjected to thermal cycling to evaluate the effect of HVOF parameters, coating thickness, substrate material and substrate surface roughness on the resistance to coating delamination and cracking. It was found that substrate surface roughness had a profound influence on the performance of a given substrate/coating system and that surface preparation techniques will need to be tailored to the specific substrate material. Also, higher particle velocity during HVOF thermal spray deposition of the iron aluminide coatings tended to result in better-performing coating/substrate systems with less delamination at the coating/substrate interface. Some combinations of HVOF parameters, coating thickness and substrate materials were found to perform extremely well even at temperatures up to 900oC. However, in some cases, substantial reactions at the interface were observed.

  12. Airfoils for wind turbine

    DOE Patents [OSTI]

    Tangler, James L.; Somers, Dan M.

    2000-01-01

    Airfoils for the tip and mid-span regions of a wind turbine blade have upper surface and lower surface shapes and contours between a leading edge and a trailing edge that minimize roughness effects of the airfoil and provide maximum lift coefficients that are largely insensitive to roughness effects. The airfoil in one embodiment is shaped and contoured to have a thickness in a range of about fourteen to seventeen percent, a Reynolds number in a range of about 1,500,000 to 2,000,000, and a maximum lift coefficient in a range of about 1.4 to 1.5. In another embodiment, the airfoil is shaped and contoured to have a thickness in a range of about fourteen percent to sixteen percent, a Reynolds number in a range of about 1,500,000 to 3,000,000, and a maximum lift coefficient in a range of about 0.7 to 1.5. Another embodiment of the airfoil is shaped and contoured to have a Reynolds in a range of about 1,500,000 to 4,000,000, and a maximum lift coefficient in a range of about 1.0 to 1.5.

  13. Exponentially decaying magnetic coupling in sputtered thin film FeNi/Cu/FeCo trilayers

    SciTech Connect (OSTI)

    Wei, Yajun Akansel, Serkan; Thersleff, Thomas; Brucas, Rimantas; Lansaker, Pia; Leifer, Klaus; Svedlindh, Peter; Harward, Ian; Celinski, Zbigniew; Ranjbar, Mojtaba; Dumas, Randy K.; Jana, Somnath; Pogoryelov, Yevgen; Karis, Olof; Åkerman, Johan

    2015-01-26

    Magnetic coupling in trilayer films of FeNi/Cu/FeCo deposited on Si/SiO{sub 2} substrates have been studied. While the thicknesses of the FeNi and FeCo layers were kept constant at 100 Å, the thickness of the Cu spacer was varied from 5 to 50 Å. Both hysteresis loop and ferromagnetic resonance results indicate that all films are ferromagnetically coupled. Micromagnetic simulations well reproduce the ferromagnetic resonance mode positions measured by experiments, enabling the extraction of the coupling constants. Films with a thin Cu spacer are found to be strongly coupled, with an effective coupling constant of 3 erg/cm{sup 2} for the sample with a 5 Å Cu spacer. The strong coupling strength is qualitatively understood within the framework of a combined effect of Ruderman-Kittel-Kasuya-Yosida and pinhole coupling, which is evidenced by transmission electron microscopy analysis. The magnetic coupling constant surprisingly decreases exponentially with increasing Cu spacer thickness, without showing an oscillatory thickness dependence. This is partially connected to the substantial interfacial roughness that washes away the oscillation. The results have implications on the design of multilayers for spintronic applications.

  14. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - PORTER-CABLE CIRCULAR SAW OENHP: 2001-04, VERSION A

    SciTech Connect (OSTI)

    Unknown

    2002-01-15

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Porter-Cable circular saw was assessed on August 15-16, 2001 (Porter-Cable No.1 and Porter-Cable No.2, respectively). During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Porter-Cable saw is a straightforward machine for cutting wood of varying thickness. The blade is fully guarded with a fixed upper and a lower retractable guard. The lower guard retracts as the blade engages the work piece. The unit is operated with an on/off guarded trigger switch and is supported with a handgrip mounted near the front of the saw. The saw is equipped with a directional nozzle, which aims sawdust away from the operator and the line of cut. An optional vacuum system, attached to the directional nozzle, is used to remove and collect dust. During the demonstration of Porter-Cable No.1, personal noise sampling indicated that one worker was under and one was at the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. During the demonstration of Porter-Cable No.2, however, both workers did exceed the Action Level with TWA's of 89.7 and 90.0 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for Porter-Cable No.1 was 3.53 milligrams per cubic meter (mg/m{sup 3}), which is lower than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Porter-Cable No.2's nuisance dust results yielded a value of 22.05 mg/m{sup 3}, which is over the PEL and TLV. The fiber analysis for the first demonstration yielded 12.9 fibers per cubic centimeter (f/cc), which is much higher than the PEL of 1 f/cc. Galson Laboratories considered the fiber analysis for the second demonstration void due to the overloading of dust on the filter. Kickback, the sudden reaction to a pinched blade, is possible with this saw and could cause the saw to lift up and out of the work piece and toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool.

  15. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - EVOLUTION 180 CIRCULAR SAW OENHP: 2001-03, VERSION A

    SciTech Connect (OSTI)

    Unknown

    2002-01-25

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated gloveboxes at the Department of Energy's (DOE) Los Alamos facility. The Evolution 180 circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Evolution 180 is a portable, metal cutting circular saw with a 7-inch diameter blade. The blade is contained within the main housing and has a retractable lower blade guard to prevent operator access to the blade during operation and shutdown. The saw is equipped with a chip collector. The maximum cutting thickness for metal is one-quarter inch and can cut steel tubing and pipe 2 inches in diameter. The unit is operated with an on/off guarded trigger switch and is supported with the hand guide mounted to the side of the saw. An adjustable lever sets the depth of the cut. The machine's circuitry will automatically shut the saw motor off if excessive overload is detected during operation. The one-half hour demonstration involved vertical and horizontal cuts and blade changes. During this process, operators experienced binding of the saw. This caused the blade to become hot, causing the sawdust collected in the chip collector to smoke. Care should be exercised to use the appropriate blade for the application, operator training, and personal protective equipment (PPE). Personal noise sampling indicated that neither worker was over the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 69.1 and 68.8 dBA. The personal noise sample taken during the special demonstration with the stainless steel plate had a TWA of 69.8 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for the Evolution 180 circular saw was 3.5 milligrams per cubic meter (mg/m{sup 3}), which is lower than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. The fiber analysis yielded 1.74 fibers per cubic centimeter (f/cc), which is above the PEL of 1 f/cc. Although the nuisance dust levels were low, fiberglass dust levels were higher than the PEL. Since fiberglass dust is known to be a strong skin irritant and a possible human carcinogen, the workers should continue to wear appropriate suits and gloves, as well as a full-face air-purifying respirator. The respirator should be equipped with a combination organic vapor and acid gas cartridge in combination with a High Particulate Air (HEPA) filter, since particulate filter, since during the demonstration, the workers complained of an odd smell, which may have been from the breakdown of the fiberglass.

  16. Impact of induced seismic events on seal integrity, Texas Gulf Coast

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Nicot, Jean-Philippe; Meckel, Timothy A.; Carr, David A.; Oldenburg, Curtis M.

    2014-12-31

    Recent publications have suggested that large-scale CO2 injection could trigger earthquakes and that even small- to moderate-sized earthquakes may threaten the seal integrity of the injection zone, and potentially damage buildings and other surface structures. In this study, we compared seal thickness to estimated fault displacement due to a single hypothetical seismic event in a selected area of the Texas Gulf Coast comprising an offshore strip of state waters along two Texas counties. To evaluate the slip generated by a single seismic event, we compiled well log information on shale/sand sequences and seismic information on fault geometric characteristics of amore » section of Lower Miocene age. The section is thousands of feet thick and is overlain and underlain by marine shales (Amph. B and Anahuac, respectively) that are relatively easy to correlate between wells. The Amph. B. shale is the secondary and ultimate seal for all injection intervals in the Lower Miocene. Given its thickness, no realistic seismic event or small series of seismic events will offset it significantly. However, this may not be true of smaller local primary seals. An analysis of geophysical logs of a total of 71 wells yielded a total of 2,871 sand / shale binary intervals. An analysis of the dedicated 3D seismic survey counted 723 fault traces at five roughly horizontal horizons within the Lower Miocene Fault displacement estimated using the product of the fault length times an uncertain multiplier coefficient assumed to follow a triangular distribution with a 10-3 to 10-5 range and a mode of 8 × 10-5. We then compared estimated single-event fault displacements to seal thicknesses by means of a Monte-Carlo analysis. Only 1.8% of thickness/displacement pairs display a displacement greater than 20% of the seal thickness. Only 0.26% of the pairs result in a displacement of half the seal thickness and only 0.05% of thickness/displacement pairs result in a clear seal rupture. The next step was to compare the magnitude of the event generated by such a displacement to documented magnitudes of “large” earthquakes generated by waterflooding and fluid disposal. Based on this analysis, we conclude that seismicity that may arise from CO2 injection appears not to be a serious complication for CO2 storage integrity, at least in the Gulf Coast area.« less

  17. Impact of induced seismic events on seal integrity, Texas Gulf Coast

    SciTech Connect (OSTI)

    Nicot, Jean-Philippe; Meckel, Timothy A.; Carr, David A.; Oldenburg, Curtis M.

    2014-12-31

    Recent publications have suggested that large-scale CO2 injection could trigger earthquakes and that even small- to moderate-sized earthquakes may threaten the seal integrity of the injection zone, and potentially damage buildings and other surface structures. In this study, we compared seal thickness to estimated fault displacement due to a single hypothetical seismic event in a selected area of the Texas Gulf Coast comprising an offshore strip of state waters along two Texas counties. To evaluate the slip generated by a single seismic event, we compiled well log information on shale/sand sequences and seismic information on fault geometric characteristics of a section of Lower Miocene age. The section is thousands of feet thick and is overlain and underlain by marine shales (Amph. B and Anahuac, respectively) that are relatively easy to correlate between wells. The Amph. B. shale is the secondary and ultimate seal for all injection intervals in the Lower Miocene. Given its thickness, no realistic seismic event or small series of seismic events will offset it significantly. However, this may not be true of smaller local primary seals. An analysis of geophysical logs of a total of 71 wells yielded a total of 2,871 sand / shale binary intervals. An analysis of the dedicated 3D seismic survey counted 723 fault traces at five roughly horizontal horizons within the Lower Miocene Fault displacement estimated using the product of the fault length times an uncertain multiplier coefficient assumed to follow a triangular distribution with a 10-3 to 10-5 range and a mode of 8 × 10-5. We then compared estimated single-event fault displacements to seal thicknesses by means of a Monte-Carlo analysis. Only 1.8% of thickness/displacement pairs display a displacement greater than 20% of the seal thickness. Only 0.26% of the pairs result in a displacement of half the seal thickness and only 0.05% of thickness/displacement pairs result in a clear seal rupture. The next step was to compare the magnitude of the event generated by such a displacement to documented magnitudes of “large” earthquakes generated by waterflooding and fluid disposal. Based on this analysis, we conclude that seismicity that may arise from CO2 injection appears not to be a serious complication for CO2 storage integrity, at least in the Gulf Coast area.

  18. Centerless-drive solar collector system

    SciTech Connect (OSTI)

    Butler, B. L.

    1985-12-24

    A parabolic-trough solar collector system is disclosed, with each collector driven to track the sun using a ring driven in centerless fashion. The parabolic troughs are made of laminated plywood or molded or formed of plastics or metals. The drive motor moves a flexible belt, i.e., chain or cable, which is routed about the drive ring on each collector. The motion of the cable moves all drive rings together to track the sun. A photodetector senses the position of the sun and provides the signal needed to drive the collectors in the correct direction.

  19. DOE Zero Energy Ready Home Case Study: Promethean Homes, Charlottesville,

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    VA | Department of Energy Promethean Homes, Charlottesville, VA DOE Zero Energy Ready Home Case Study: Promethean Homes, Charlottesville, VA DOE Zero Energy Ready Home Case Study: Promethean Homes, Charlottesville, VA Case study of a DOE Zero Energy Ready home in Charlottesville, VA, that achieves a HERS 33 without PV. The 2,572-ft2 custom home with daylight basement, has 2x6 advanced framed walls filled with R-21 cellulose plus 2-in. rigid mineral wool insulation over the plywood sheathing,

  20. DOE Zero Energy Ready Home Case Study: Mandalay Homes, Prescott Valley, AZ

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy Mandalay Homes, Prescott Valley, AZ DOE Zero Energy Ready Home Case Study: Mandalay Homes, Prescott Valley, AZ DOE Zero Energy Ready Home Case Study: Mandalay Homes, Prescott Valley, AZ Case study of a DOE Zero Energy Ready home in northern AZ that achieved a HERS score of 48 without PV or 25 if 3.5 kW PV were added. The two-story, 2,469-ft2 production home has 2x4 walls filled with R-13 open-cell spray foam plus 1-in. rigid foam over plywood sheathing, a sealed R-20

  1. Effects of ruthenium seed layer on the microstructure and spin dynamics of thin permalloy films

    SciTech Connect (OSTI)

    Jin Lichuan; Zhang Huaiwu; Tang Xiaoli; Bai Feiming; Zhong Zhiyong

    2013-02-07

    The spin dynamics and microstructure properties of a sputtered 12 nm Ni{sub 81}Fe{sub 19} thin film have been enhanced by the use of a ruthenium seed layer. Both the ferromagnetic resonance field and linewidth are enhanced dramatically as the thickness of ruthenium seed layer is increased. The surface anisotropy energy constant can also be largely tailored from 0.06 to 0.96 erg/cm{sup -2} by changing the seed layer thickness. The changes to the dynamics magnetization properties are caused by both ruthenium seed layer induced changes in the Ni{sub 81}Fe{sub 19} structure properties and surface topography properties. Roughness induced inhomogeneous linewidth broadening is also seen. The damping constant is highly tunable via the ruthenium thickness. This approach can be used to tailor both the structure and spin dynamic properties of thin Ni{sub 81}Fe{sub 19} films over a wide range. And it may benefit the applications of spin dynamics and spin current based devices.

  2. A novel solution to the gated x-ray detector gain droop problem

    SciTech Connect (OSTI)

    Oertel, J. A. Archuleta, T. N.

    2014-11-15

    Microchannel plate (MCP), microstrip transmission line based, gated x-ray detectors used at the premier ICF laser facilities have a drop in gain as a function of mircostrip length that can be greater than 50% over 40 mm. These losses are due to ohmic losses in a microstrip coating that is less than the optimum electrical skin depth. The electrical skin depth for a copper transmission line at 3 GHz is 1.2 μm while the standard microstrip coating thickness is roughly half a single skin depth. Simply increasing the copper coating thickness would begin filling the MCP pores and limit the number of secondary electrons created in the MCP. The current coating thickness represents a compromise between gain and ohmic loss. We suggest a novel solution to the loss problem by overcoating the copper transmission line with five electrical skin depths (∼6 μm) of Beryllium. Beryllium is reasonably transparent to x-rays above 800 eV and would improve the carrier current on the transmission line. The net result should be an optically flat photocathode response with almost no measurable loss in voltage along the transmission line.

  3. Efficiency of a multilayer-Laue-lens with a 102 μm aperture

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Macrander, Albert T.; Kubec, Adam; Conley, Raymond; Bouet, Nathalie; Zhou, Juan; Wojcik, Michael; Maser, Jorg

    2015-08-25

    A multilayer-Laue-lens (MLL) comprised of WSi2/Al layers stacked to a full thickness of 102 microns was characterized for its diffraction efficiency and dynamical diffraction properties by x-ray measurements made in the far field. The achieved aperture roughly doubles the previous maximum reported aperture for an MLL, thereby doubling the working distance. Negative and positive first orders were found to have 14.2 % and 13.0 % efficiencies, respectively. A section thickness of 9.6 μm was determined from Laue-case thickness fringes in the diffraction data. A background gas consisting of 90 % Ar and 10 % N2 was used for sputtering. Thismore » material system was chosen to reduce grown-in stress as the multilayer is deposited. Although some regions of the full MLL exhibited defects, the presently reported results were obtained for a region devoid of defects. The data compare well to dynamical diffraction calculations with Coupled Wave Theory (CWT) which provided confirmation of the optical constants and densities assumed for the CWT calculations.« less

  4. Air Gap Effects in LX-17

    SciTech Connect (OSTI)

    Souers, P C; Ault, S; Avara, R; Bahl, K L; Boat, R; Cunningham, B; Gidding, D; Janzen, J; Kuklo, D; Lee, R; Lauderbach, L; Weingart, W C; Wu, B; Winer, K

    2005-09-26

    Three experiments done over twenty years on gaps in LX-17 are reported. For the detonation front moving parallel to the gaps, jets of gas products were seen coming from the gaps at velocities greater than the detonation velocity. A case can be made that the jet velocity increased with gap thickness but the data is scattered. For the detonation front moving transverse to the gap, time delays were seen. The delays roughly increase with gap width, going from 0-70 ns at 'zero gap' to around 300 ns at 0.5-1 mm gap. Larger gaps of up to 6 mm width almost certainly stopped the detonation, but this was not proved. Real-time resolution of the parallel jets and determination of the actual re-detonation or failure in the transverse case needs to be done in future experiments.

  5. Optical stress generator and detector

    DOE Patents [OSTI]

    Maris, Humphrey J.; Stoner, Robert J

    1999-01-01

    Disclosed is a system for the characterization of thin films and interfaces between thin films through measurements of their mechanical and thermal properties. In the system light is absorbed in a thin film or in a structure made up of several thin films, and the change in optical transmission or reflection is measured and analyzed. The change in reflection or transmission is used to give information about the ultrasonic waves that are produced in the structure. The information that is obtained from the use of the measurement methods and apparatus of this invention can include: (a) a determination of the thickness of thin films with a speed and accuracy that is improved compared to earlier methods; (b) a determination of the thermal, elastic, and optical properties of thin films; (c) a determination of the stress in thin films; and (d) a characterization of the properties of interfaces, including the presence of roughness and defects.

  6. Optical stress generator and detector

    DOE Patents [OSTI]

    Maris, Humphrey J.; Stoner, Robert J

    2001-01-01

    Disclosed is a system for the characterization of thin films and interfaces between thin films through measurements of their mechanical and thermal properties. In the system light is absorbed in a thin film or in a structure made up of several thin films, and the change in optical transmission or reflection is measured and analyzed. The change in reflection or transmission is used to give information about the ultrasonic waves that are produced in the structure. The information that is obtained from the use of the measurement methods and apparatus of this invention can include: (a) a determination of the thickness of thin films with a speed and accuracy that is improved compared to earlier methods; (b) a determination of the thermal, elastic, and optical properties of thin films; (c) a determination of the stress in thin films; and (d) a characterization of the properties of interfaces, including the presence of roughness and defects.

  7. Optical stress generator and detector

    DOE Patents [OSTI]

    Maris, Humphrey J.; Stoner, Robert J.

    1998-01-01

    Disclosed is a system for the characterization of thin films and interfaces between thin films through measurements of their mechanical and thermal properties. In the system light is absorbed in a thin film or in a structure made up of several thin films, and the change in optical transmission or reflection is measured and analyzed. The change in reflection or transmission is used to give information about the ultrasonic waves that are produced in the structure. The information that is obtained from the use of the measurement methods and apparatus of this invention can include: (a) a determination of the thickness of thin films with a speed and accuracy that is improved compared to earlier methods; (b) a determination of the thermal, elastic, and optical properties of thin films; (c) a determination of the stress in thin films; and (d) a characterization of the properties of interfaces, including the presence of roughness and defects.

  8. Optical stress generator and detector

    DOE Patents [OSTI]

    Maris, H.J.; Stoner, R.J.

    1998-05-05

    Disclosed is a system for the characterization of thin films and interfaces between thin films through measurements of their mechanical and thermal properties. In the system light is absorbed in a thin film or in a structure made up of several thin films, and the change in optical transmission or reflection is measured and analyzed. The change in reflection or transmission is used to give information about the ultrasonic waves that are produced in the structure. The information that is obtained from the use of the measurement methods and apparatus of this invention can include: (a) a determination of the thickness of thin films with a speed and accuracy that is improved compared to earlier methods; (b) a determination of the thermal, elastic, and optical properties of thin films; (c) a determination of the stress in thin films; and (d) a characterization of the properties of interfaces, including the presence of roughness and defects. 32 figs.

  9. Optical stress generator and detector

    DOE Patents [OSTI]

    Maris, Humphrey J.; Stoner, Robert J

    2002-01-01

    Disclosed is a system for the characterization of thin films and interfaces between thin films through measurements of their mechanical and thermal properties. In the system light is absorbed in a thin film or in a structure made up of several thin films, and the change in optical transmission or reflection is measured and analyzed. The change in reflection or transmission is used to give information about the ultrasonic waves that are produced in the structure. The information that is obtained from the use of the measurement methods and apparatus of this invention can include: (a) a determination of the thickness of thin films with a speed and accuracy that is improved compared to earlier methods; (b) a determination of the thermal, elastic, and optical properties of thin films; (c) a determination of the stress in thin films; and (d) a characterization of the properties of interfaces, including the presence of roughness and defects.

  10. Highly conducting SrMoO{sub 3} thin films for microwave applications

    SciTech Connect (OSTI)

    Radetinac, Aldin Mani, Arzhang; Ziegler, Jrgen; Alff, Lambert; Komissinskiy, Philipp; Melnyk, Sergiy; Nikfalazar, Mohammad; Zheng, Yuliang; Jakoby, Rolf

    2014-09-15

    We have measured the microwave resistance of highly conducting perovskite oxide SrMoO{sub 3} thin film coplanar waveguides. The epitaxial SrMoO{sub 3} thin films were grown by pulsed laser deposition and showed low mosaicity and smooth surfaces with a root mean square roughness below 0.3?nm. Layer-by-layer growth could be achieved for film thicknesses up to 400?nm as monitored by reflection high-energy electron diffraction and confirmed by X-ray diffraction. We obtained a constant microwave resistivity of 29???cm between 0.1 and 20?GHz by refining the frequency dependence of the transmission coefficients. Our result shows that SrMoO{sub 3} is a viable candidate as a highly conducting electrode material for all-oxide microwave electronic devices.

  11. Ultrathin polycrystalline 6,13-Bis(triisopropylsilylethynyl)-pentacene films

    SciTech Connect (OSTI)

    Jung, Min-Cherl; Zhang, Dongrong; Nikiforov, Gueorgui O.; Lee, Michael V.; Qi, Yabing; Joo Shin, Tae; Ahn, Docheon; Lee, Han-Koo; Baik, Jaeyoon; Shin, Hyun-Joon

    2015-03-15

    Ultrathin (<6?nm) polycrystalline films of 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-P) are deposited with a two-step spin-coating process. The influence of spin-coating conditions on morphology of the resulting film was examined by atomic force microscopy. Film thickness and RMS surface roughness were in the range of 4.06.1 and 0.61.1?nm, respectively, except for small holes. Polycrystalline structure was confirmed by grazing incidence x-ray diffraction measurements. Near-edge x-ray absorption fine structure measurements suggested that the plane through aromatic rings of TIPS-P molecules was perpendicular to the substrate surface.

  12. Effect of Al-mole fraction in Al{sub x}Ga{sub 1−x}N grown by MOCVD

    SciTech Connect (OSTI)

    Jayasakthi, M. Ramesh, R. Prabakaran, K. Loganathan, R. Kuppulingam, B. Balaji, M. Arivazhagan, P. Sankaranarayanan, S. Singh, Shubra Baskar, K.

    2014-04-24

    AlGaN/AlN layers were grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrates. The Al{sub x}Ga{sub 1−x}N layer composition was varied from 15% to 25%. The crystalline quality, thickness and aluminum (Al) composition of AlGaN were determined using high resolution X-ray diffraction (HRXRD). The growth rate decreases on increasing Al composition. Reciprocal space mapping (RSM) was used to estimate the strain and relaxation between AlGaN and AlN. The optical properties of AlGaN layers were investigated by room temperature Photoluminescence (PL). The AlGaN peak shifts towards lower wavelength with Al composition. The surface morphology of AlGaN was studied by atomic force microscopy (AFM). Root mean square (RMS) roughness values were found to be increased in AlGaN layers with composition.

  13. Installation and commissioning of a large area coating system for neutron and X-ray optical devices

    SciTech Connect (OSTI)

    Biswas, A. Haque, Sk. Maidul Misal, J. Sampathkumar, R.; Ajaykumar,; Bhattacharyya, D.; Sahoo, N. K.; Lagoo, K. D.; Veerapur, R. D.; Padmanabhan, M.; Puri, R. K.; Bhattacharya, Debarati

    2014-04-24

    A 9 meter long DC/RF sputtering cylindrical coating system which is designed and built indigenously for coating of neutron supermirrors and grazing incidence hard X-ray mirrors on large area substrates has been installed and commissioned recently. The performance of the system has been tested by depositing Ti films on glass substrate of 1500mm X 150mm size. By depositing Ti films on several small area c-Si substrates placed over the length and breadth of the substrate holder, and by subsequent characterization by GIXR measurement, it has been observed that films with bulk-like density and very low surface roughness can be obtained in the above system. The thickness uniformity achieved in the deposited films is within 3.5% over the 1500mm length and within 4.8% over the 150mm width.

  14. Quartz resonator fluid density and viscosity monitor

    DOE Patents [OSTI]

    Martin, Stephen J.; Wiczer, James J.; Cernosek, Richard W.; Frye, Gregory C.; Gebert, Charles T.; Casaus, Leonard; Mitchell, Mary A.

    1998-01-01

    A pair of thickness-shear mode resonators, one smooth and one with a textured surface, allows fluid density and viscosity to be independently resolved. A textured surface, either randomly rough or regularly patterned, leads to trapping of liquid at the device surface. The synchronous motion of this trapped liquid with the oscillating device surface allows the device to weigh the liquid; this leads to an additional response that depends on liquid density. This additional response enables a pair of devices, one smooth and one textured, to independently resolve liquid density and viscosity; the difference in responses determines the density while the smooth device determines the density-viscosity product, and thus, the pair determines both density and viscosity.

  15. Textured-surface quartz resonator fluid density and viscosity monitor

    DOE Patents [OSTI]

    Martin, Stephen J.; Wiczer, James J.; Cernosek, Richard W.; Frye, Gregory C.; Gebert, Charles T.; Casaus, Leonard; Mitchell, Mary A.

    1998-08-25

    A pair of thickness-shear mode resonators, one smooth and one with a textured surface, allows fluid density and viscosity to be independently resolved. A textured surface, either randomly rough or regularly patterned, leads to trapping of liquid at the device surface. The synchronous motion of this trapped liquid with the oscillating device surface allows the device to weigh the liquid; this leads to an additional response that depends on liquid density. This additional response enables a pair of devices, one smooth and one textured, to independently resolve liquid density and viscosity; the difference in responses determines the density while the smooth device determines the density-viscosity product, and thus, the pair determines both density and viscosity.

  16. Optical, electrical and surface properties of annealed CdO:Mg thin films prepared by spray pyrolysis

    SciTech Connect (OSTI)

    Karakaya, Seniye E-mail: oozbas@ogu.edu.tr; Ozbas, Omer E-mail: oozbas@ogu.edu.tr

    2013-12-16

    The use of transparent conducting oxides in optoelectronic and photovoltaic devices has encouraged research on this field in recent years. Especially, cadmium oxide is a promising material for solar cell application but also for photodiodes and gas sensors. Mg doped CdO (CdO:Mg) films have been prepared on glass substrates by the ultrasonic spray pyrolysis (USP) technique. After the production, the films have been annealed in air atmosphere at 475C and half hour. Results on surface, optical and electrical properties of the films as a function of the thermal annealing have been reported. Thicknesses of the films have been determined by the filmetrics thin film measurement system. Transmission and absorbance spectra have been taken by UV-vis spectrophotometer. Atomic Force Microscopy (AFM) analysis indicates that the roughness of the surface decreases upon increasing Mg concentration. The minimum resistivity value of the films was 210{sup ?3} ? cm.

  17. Evidence of a rearrangement of the surface structure in titanium phthalocyanine sensors induced by the interaction with nitrogen oxides molecules

    SciTech Connect (OSTI)

    Generosi, A.; Paci, B.; Albertini, V. Rossi; Perfetti, P.; Paoletti, A.M.; Pennesi, G.; Rossi, G.; Caminiti, R.

    2005-10-31

    Thin-film samples of titanium phthalocyanine, a sensor of environmental pollutants, were studied by time resolved energy-dispersive x-ray reflectivity (EDXR). This original method demonstrated to be an ideal tool to follow the evolution of the films morphology upon gas exposure, in situ, also allowing an unexpected response of the sensors to be detected. Indeed, while the increase in thickness showed the characteristic feature of a 'breathing-like' expansion, already observed in other metal-Pc, the curve of roughness versus exposure time exhibited a peak. This effect, in some cases evident by observation with the naked eye the EDXR data, was attributed to a surface structure rearrangement process.

  18. Temperature sensitive surfaces and methods of making same

    DOE Patents [OSTI]

    Liang, Liang [Richland, WA; Rieke, Peter C [Pasco, WA; Alford, Kentin L [Pasco, WA

    2002-09-10

    Poly-n-isopropylacrylamide surface coatings demonstrate the useful property of being able to switch charateristics depending upon temperature. More specifically, these coatings switch from being hydrophilic at low temperature to hydrophobic at high temperature. Research has been conducted for many years to better characterize and control the properties of temperature sensitive coatings. The present invention provides novel temperature sensitive coatings on articles and novel methods of making temperature sensitive coatings that are disposed on the surfaces of various articles. These novel coatings contain the reaction products of n-isopropylacrylamide and are characterized by their properties such as advancing contact angles. Numerous other characteristics such as coating thickness, surface roughness, and hydrophilic-to-hydrophobic transition temperatures are also described. The present invention includes articles having temperature-sensitve coatings with improved properties as well as improved methods for forming temperature sensitive coatings.

  19. Dynamics of spintronic materials: Exploration in the time and frequency domain

    SciTech Connect (OSTI)

    Zabel, Hartmut

    2014-12-14

    X-ray and neutron reflectivity are mature experimental techniques for the exploration of film thicknesses and interface roughnesses on the nanoscale. Combining with photon and neutron polarization, these methods can be carried forward to the analysis of magnetic thin films and magnetic domain structures. New opportunities open up when these methods are used either in the time or in the frequency domain. Then dynamical processes can be studied such as domain oscillations, domain propagation, precession of spins, and damping effects. Two methods are discussed which have been developed recently: polarized neutron reflectivity from magnetic films in an alternating magnetic field and time resolved resonant magnetic x-ray reflectivity of the free precessional dynamics in films and multilayers.

  20. Low Speed Carbon Deposition Process for Hermetic Optical Fibers

    SciTech Connect (OSTI)

    ABRAMCZYK,JAROSLAW; ARTHUR,SARA E. TALLANT,DAVID R.; HIKANSSON,ADAM S.; LINDHOLM,ERIC A.; LO,JIE

    1999-09-29

    For optical fibers used in adverse environments, a carbon coating is frequently deposited on the fiber surface to prevent water and hydrogen ingression that lead respectively to strength degradation through fatigue and hydrogen-induced attenuation. The deposition of a hermetic carbon coating onto an optical fiber during the draw process holds a particular challenge when thermally-cured specialty coatings are subsequently applied because of the slower drawing rate. In this paper, we report on our efforts to improve the low-speed carbon deposition process by altering the composition and concentration of hydrocarbon precursor gases. The resulting carbon layers have been analyzed for electrical resistance, Raman spectra, coating thickness, and surface roughness, then compared to strength data and dynamic fatigue behavior.

  1. Thermally-induced transition of lamellae orientation in block-copolymer films on ‘neutral’ nanoparticle-coated substrates

    SciTech Connect (OSTI)

    Yager, Kevin G.; Forrey, Christopher; Singh, Gurpreet; Satija, Sushil K.; Page, Kirt A.; Patton, Derek L.; Jones, Ronald L.; Karin, Alamgir; Douglas, Jack F.

    2015-06-01

    Block-copolymer orientation in thin films is controlled by the complex balance between interfacial free energies, including the inter-block segregation strength, the surface tensions of the blocks, and the relative substrate interactions. While block-copolymer lamellae orient horizontally when there is any preferential affinity of one block for the substrate, we recently described how nanoparticle-roughened substrates can be used to modify substrate interactions. We demonstrate how such ‘neutral’ substrates can be combined with control of annealing temperature to generate vertical lamellae orientations throughout a sample, at all thicknesses. We observe an orientational transition from vertical to horizontal lamellae upon heating, as confirmed using a combination of atomic force microscopy (AFM), neutron reflectometry (NR) and rotational small-angle neutron scattering (RSANS). Using molecular dynamics (MD) simulations, we identify substrate-localized distortions to the lamellar morphology as the physical basis of the novel behavior. In particular, under strong segregation conditions, bending of horizontal lamellae induce a large energetic cost. At higher temperatures, the energetic cost of conformal deformations of lamellae over the rough substrate is reduced, returning lamellae to the typical horizontal orientation. Thus, we find that both surface interactions and temperature play a crucial role in dictating block-copolymer lamellae orientation. As a result, our combined experimental and simulation findings suggest that controlling substrate roughness should provide a useful and robust platform for controlling block-copolymer orientation in applications of these materials.

  2. Etching radical controlled gas chopped deep reactive ion etching

    DOE Patents [OSTI]

    Olynick, Deidre; Rangelow, Ivo; Chao, Weilun

    2013-10-01

    A method for silicon micromachining techniques based on high aspect ratio reactive ion etching with gas chopping has been developed capable of producing essentially scallop-free, smooth, sidewall surfaces. The method uses precisely controlled, alternated (or chopped) gas flow of the etching and deposition gas precursors to produce a controllable sidewall passivation capable of high anisotropy. The dynamic control of sidewall passivation is achieved by carefully controlling fluorine radical presence with moderator gasses, such as CH.sub.4 and controlling the passivation rate and stoichiometry using a CF.sub.2 source. In this manner, sidewall polymer deposition thicknesses are very well controlled, reducing sidewall ripples to very small levels. By combining inductively coupled plasmas with controlled fluorocarbon chemistry, good control of vertical structures with very low sidewall roughness may be produced. Results show silicon features with an aspect ratio of 20:1 for 10 nm features with applicability to nano-applications in the sub-50 nm regime. By comparison, previous traditional gas chopping techniques have produced rippled or scalloped sidewalls in a range of 50 to 100 nm roughness.

  3. Thermally-induced transition of lamellae orientation in block-copolymer films on ‘neutral’ nanoparticle-coated substrates

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yager, Kevin G.; Forrey, Christopher; Singh, Gurpreet; Satija, Sushil K.; Page, Kirt A.; Patton, Derek L.; Jones, Ronald L.; Karin, Alamgir; Douglas, Jack F.

    2015-06-01

    Block-copolymer orientation in thin films is controlled by the complex balance between interfacial free energies, including the inter-block segregation strength, the surface tensions of the blocks, and the relative substrate interactions. While block-copolymer lamellae orient horizontally when there is any preferential affinity of one block for the substrate, we recently described how nanoparticle-roughened substrates can be used to modify substrate interactions. We demonstrate how such ‘neutral’ substrates can be combined with control of annealing temperature to generate vertical lamellae orientations throughout a sample, at all thicknesses. We observe an orientational transition from vertical to horizontal lamellae upon heating, as confirmedmore » using a combination of atomic force microscopy (AFM), neutron reflectometry (NR) and rotational small-angle neutron scattering (RSANS). Using molecular dynamics (MD) simulations, we identify substrate-localized distortions to the lamellar morphology as the physical basis of the novel behavior. In particular, under strong segregation conditions, bending of horizontal lamellae induce a large energetic cost. At higher temperatures, the energetic cost of conformal deformations of lamellae over the rough substrate is reduced, returning lamellae to the typical horizontal orientation. Thus, we find that both surface interactions and temperature play a crucial role in dictating block-copolymer lamellae orientation. As a result, our combined experimental and simulation findings suggest that controlling substrate roughness should provide a useful and robust platform for controlling block-copolymer orientation in applications of these materials.« less

  4. Thin silicon foils produced by epoxy-induced spalling of silicon for high efficiency solar cells

    SciTech Connect (OSTI)

    Martini, R.; Kepa, J.; Stesmans, A.; Debucquoy, M.; Depauw, V.; Gonzalez, M.; Gordon, I.; Poortmans, J.

    2014-10-27

    We report on the drastic improvement of the quality of thin silicon foils produced by epoxy-induced spalling. In the past, researchers have proposed to fabricate silicon foils by spalling silicon substrates with different stress-inducing materials to manufacture thin silicon solar cells. However, the reported values of effective minority carrier lifetime of the fabricated foils remained always limited to ∼100 μs or below. In this work, we investigate epoxy-induced exfoliated foils by electron spin resonance to analyze the limiting factors of the minority carrier lifetime. These measurements highlight the presence of disordered dangling bonds and dislocation-like defects generated by the exfoliation process. A solution to remove these defects compatible with the process flow to fabricate solar cells is proposed. After etching off less than 1 μm of material, the lifetime of the foil increases by more than a factor of 4.5, reaching a value of 461 μs. This corresponds to a lower limit of the diffusion length of more than 7 times the foil thickness. Regions with different lifetime correlate well with the roughness of the crack surface which suggests that the lifetime is now limited by the quality of the passivation of rough surfaces. The reported values of the minority carrier lifetime show a potential for high efficiency (>22%) thin silicon solar cells.

  5. DYNA3D analysis of the DT-20 shipping container

    SciTech Connect (OSTI)

    Logan, R.W.; Lovejoy, S.C.

    1991-08-22

    A DYNA3D model of the DT-20 shipping container was constructed. Impact onto a rigid steel surface at a velocity of 44 ft/sec (30 foot gravity drop) was studied. The orientation of most interest was a side-drop, but end and corner drops were also studied briefly. The assembly for the baseline side impact contained a 150 lb. payload. During this drop, the outer drum sustains plastic strains of up to 0.15, with most the deformation near the rim. The plywood/Celotex packing is crushed about 3 inches. The inner sealed can sees significant stresses, but barely reaches the onset of yielding in some local areas. Based on hand calculations, the bolts joining the can halves could see stresses near 50 ksi. It is felt that overall, the container should survive this drop. However, detailed modeling of the rim closure and the center bolted joint was not possible due to time constraints. Furthermore, better material models and properties are needed for the Celotex, plywood, and honeycomb in particular. 39 figs., 1 tab.

  6. Assessment of underground coal gasification in bituminous coals: catalog of bituminous coals and site selection. Appendix A. National coal resource data system: Ecoal, Wcoal, and Bmalyt. Final report, Phase I. [Bituminous coal; by state; coal seam depth and thickness; identification

    SciTech Connect (OSTI)

    1982-01-31

    Appendix A is a catalog of the bituminous coal in 29 states of the contiguous United States which contain identified bituminous coal resources.

  7. Technical Comparative Analysis of "Best of Breed" Turnkey Si-Based Processes and Equipment, to be Used to Produce a Combined Multi-entity Research and Development Technology Roadmap for Thick and Thin Silicon PV

    SciTech Connect (OSTI)

    Hovel, Harold; Prettyman, Kevin

    2015-03-27

    A side-by-side analysis was done on then currently available technology, along with roadmaps to push each particular option forward. Variations in turnkey line processes can and do result in finished solar device performance. Together with variations in starting material quality, the result is a distribution of effciencies. Forensic analysis and characterization of each crystalline Si based technology will determine the most promising approach with respect to cost, efficiency and reliability. Forensic analysis will also shed light on the causes of binning variations. Si solar cells were forensically analyzed from each turn key supplier using a host of techniques

  8. Total reflection inelastic x-ray scattering from a 10 nm thick La{sub 0.6}Sr{sub 0.2}CoO{sub 3} thin film.

    SciTech Connect (OSTI)

    Fister, T. T.; Fong, D. D.; Eastman, J. A.; Iddir, H.; Zapol, P.; Fuoss, P. H.; Balasubramanian, M.; Gordon, R. A.; Balasubramaniam, K. R.; Salvador, P. A.; Simon Fraser Univ.; Carnegie Mellon Univ.

    2011-01-18

    To study equilibrium changes in composition, valence, and electronic structure near the surface and into the bulk, we demonstrate the use of a new approach, total-reflection inelastic x-ray scattering, as a sub-keV spectroscopy capable of depth profiling chemical changes in thin films with nanometer resolution. By comparing data acquired under total x-ray reflection and penetrating conditions, we are able to separate the O K-edge spectra from a 10 nm La{sub 0.6}Sr{sub 0.4}CoO{sub 3} thin film from that of the underlying SrTiO{sub 3} substrate. With a smaller wavelength probe than comparable soft x-ray absorption measurements, we also describe the ability to easily access dipole-forbidden final states, using the dramatic evolution of the La N{sub 4,5} edge with momentum transfer as an example.

  9. Developing regionalized models of lithospheric thickness and velocity structure across Eurasia and the Middle East from jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities

    SciTech Connect (OSTI)

    Julia, J; Nyblade, A; Hansen, S; Rodgers, A; Matzel, E

    2009-07-06

    In this project, we are developing models of lithospheric structure for a wide variety of tectonic regions throughout Eurasia and the Middle East by regionalizing 1D velocity models obtained by jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities. We expect the regionalized velocity models will improve our ability to predict travel-times for local and regional phases, such as Pg, Pn, Sn and Lg, as well as travel-times for body-waves at upper mantle triplication distances in both seismic and aseismic regions of Eurasia and the Middle East. We anticipate the models will help inform and strengthen ongoing and future efforts within the NNSA labs to develop 3D velocity models for Eurasia and the Middle East, and will assist in obtaining model-based predictions where no empirical data are available and for improving locations from sparse networks using kriging. The codes needed to conduct the joint inversion of P-wave receiver functions (PRFs), S-wave receiver functions (SRFs), and dispersion velocities have already been assembled as part of ongoing research on lithospheric structure in Africa. The methodology has been tested with synthetic 'data' and case studies have been investigated with data collected at an open broadband stations in South Africa. PRFs constrain the size and S-P travel-time of seismic discontinuities in the crust and uppermost mantle, SRFs constrain the size and P-S travel-time of the lithosphere-asthenosphere boundary, and dispersion velocities constrain average S-wave velocity within frequency-dependent depth-ranges. Preliminary results show that the combination yields integrated 1D velocity models local to the recording station, where the discontinuities constrained by the receiver functions are superimposed to a background velocity model constrained by the dispersion velocities. In our first year of this project we will (i) generate 1D velocity models for open broadband seismic stations in the western half of the study area (Eurasia and the Middle East) and (ii) identify well located seismic events with event-station paths isolated to individual tectonic provinces within the study area and collect broadband waveforms and source parameters for the selected events. The 1D models obtained from the joint inversion will then be combined with published geologic terrain maps to produce regionalized models for distinctive tectonic areas within the study area, and the models will be validated through full waveform modeling of well-located seismic events recorded at local and regional distances.

  10. Pulsed laser deposition of AlMgB14 thin films

    SciTech Connect (OSTI)

    Russell, Alan; Bastawros, Ashraf; Tan, Xiaoli

    2008-11-18

    Hard, wear-resistant coatings of thin film borides based on AlMgB{sub 14} have the potential to be applied industrially to improve the tool life of cutting tools and pump vanes and may account for several million dollars in savings as a result of reduced wear on these parts. Past work with this material has shown that it can have a hardness of up to 45GPa and be fabricated into thin films with a similar hardness using pulsed laser deposition. These films have already been shown to be promising for industrial applications. Cutting tools coated with AlMgB{sub 14} used to mill titanium alloys have been shown to substantially reduce the wear on the cutting tool and extend its cutting life. However, little research into the thin film fabrication process using pulsed laser deposition to make AlMgB{sub 14} has been conducted. In this work, research was conducted into methods to optimize the deposition parameters for the AlMgB{sub 14} films. Processing methods to eliminate large particles on the surface of the AlMgB{sub 14} films, produce films that were at least 1m thick, reduce the surface roughness of the films, and improve the adhesion of the thin films were investigated. Use of a femtosecond laser source rather than a nanosecond laser source was found to be effective in eliminating large particles considered detrimental to wear reduction properties from the films. Films produced with the femtosecond laser were also found to be deposited at a rate 100 times faster than those produced with the nanosecond laser. However, films produced with the femtosecond laser developed a relatively high RMS surface roughness around 55nm. Attempts to decrease the surface roughness were largely unsuccessful. Neither increasing the surface temperature of the substrate during deposition nor using a double pulse to ablate the material was found to be extremely successful to reduce the surface roughness. Finally, the adhesion of the thin films to M2 tool steel substrates, assessed using the Rockwell C indentation adhesion test, was found to be substantially improved by the deposition of a titanium interlayer, but unaffected by increasing the temperature of the substrates. The titanium was found to improve the adhesion strength of the films because it reacted with both the steel and the AlMgB{sub 14} compound to form new compounds. Ultimately, it was concluded that the films with the best properties were produced with a femtosecond pulsed laser and were deposited on top of a titanium interlayer to improve the thin film adhesion.

  11. The interstellar medium and star formation in edge-on galaxies. II. NGC 4157, 4565, and 5907

    SciTech Connect (OSTI)

    Yim, Kijeong; Wong, Tony; Xue, Rui; Rand, Richard J.; Rosolowsky, Erik; Hulst, J. M. van der; Benjamin, Robert; Murphy, Eric J.

    2014-12-01

    We present a study of the vertical structure of the gaseous and stellar disks in a sample of edge-on galaxies (NGC 4157, 4565, and 5907) using BIMA/CARMA {sup 12}COJ=1→0, VLA Hi, and Spitzer 3.6 μm data. In order to take into account projection effects when we measure the disk thickness as a function of radius, we first obtain the inclination by modeling the radio data. Using the measurement of the disk thicknesses and the derived radial profiles of gas and stars, we estimate the corresponding volume densities and vertical velocity dispersions. Both stellar and gas disks have smoothly varying scale heights and velocity dispersions, contrary to assumptions of previous studies. Using the velocity dispersions, we find that the gravitational instability parameter Q follows a fairly uniform profile with radius and is ⩾1 across the star-forming disk. The star formation law has a slope that is significantly different from those found in more face-on galaxy studies, both in deprojected and pixel-by-pixel plots. Midplane gas pressure based on the varying scale heights and velocity dispersions appears to roughly hold a power-law correlation with the midplane volume density ratio.

  12. Influence of strain induced by AlN nucleation layer on the electrical properties of AlGaN/GaN heterostructures on Si(111) substrate

    SciTech Connect (OSTI)

    Christy, Dennis; Watanabe, Arata; Egawa, Takashi

    2014-10-15

    The crack-free metal-organic chemical vapor deposition (MOCVD) grown AlGaN/GaN heterostructures on Si substrate with modified growth conditions of AlN nucleation layer (NL) and its influence on the electrical and structural properties of conductive GaN layer are presented. From the Hall electrical measurements, a gradual decrease of two-dimensional electron gas (2DEG) concentration near heterointerface as the function of NL thickness is observed possibly due to the reduction in difference of piezoelectric polarization charge densities between AlGaN and GaN layers. It also indicates that the minimum tensile stress and a relatively less total dislocation density for high pressure grown NL can ensure a 20 % increment in mobility at room temperature irrespective of the interface roughness. The thickness and pressure variations in NL and the subsequent changes in growth mode of AlN contributing to the post growth residual tensile stress are investigated using X-ray diffraction and Raman scattering experiments, respectively. The post growth intrinsic residual stress in top layers of heterostructures arises from lattice mismatches, NL parameters and defect densities in GaN. Hence, efforts to reduce the intrinsic residual stress in current conducting GaN layer give an opportunity to further improve the electrical characteristics of AlGaN/GaN device structures on Si.

  13. Modelling Sawing of Metal Tubes Through FEM Simulation

    SciTech Connect (OSTI)

    Bort, C. M. Giorgio; Bosetti, P.; Bruschi, S.

    2011-05-04

    The paper presents the development of a numerical model of the sawing process of AISI 304 thin tubes, which is cut through a circular blade with alternating roughing and finishing teeth. The numerical simulation environment is the three-dimensional FEM software Deform v.10.1. The teeth actual trajectories were determined by a blade kinematics analysis developed in Matlab. Due to the manufacturing rolling steps and subsequent welding stage, the tube material is characterized by a gradient of properties along its thickness. Consequently, a simplified cutting test was set up and carried out in order to identify the values of relevant material parameters to be used in the numerical model. The dedicated test was the Orthogonal Tube Cutting test (OTC), which was performed on an instrumented lathe. The proposed numerical model was validated by comparing numerical results and experimental data obtained from sawing tests carried out on an industrial machine. The following outputs were compared: the cutting force, the chip thickness, and the chip contact area.

  14. Ellipsometry characterization of polycrystalline ZnO layers with the modeling of carrier concentration gradient: Effects of grain boundary, humidity, and surface texture

    SciTech Connect (OSTI)

    Sago, Keisuke; Fujiwara, Hiroyuki; Kuramochi, Hideto; Iigusa, Hitoshi; Utsumi, Kentaro

    2014-04-07

    Spectroscopic ellipsometry (SE) has been applied to study the effects of grain boundary, humidity, and surface texture on the carrier transport properties of Al-doped ZnO layers fabricated by dc and rf magnetron sputtering. In the SE analysis, the variation in the free carrier absorption toward the growth direction, induced by the ZnO grain growth on foreign substrates, has been modeled explicitly by adopting a multilayer model in which the optical carrier concentration (N{sub opt}) varies continuously with a constant optical mobility (?{sub opt}). The effect of the grain boundary has been studied by comparing ?{sub opt} with Hall mobility (?{sub Hall}). The change in ?{sub Hall}/?{sub opt} indicates a sharp structural transition of the ZnO polycrystalline layer at a thickness of d???500?nm, which correlates very well with the structure confirmed by transmission electron microscopy. In particular, below the transition thickness, the formation of the high density grain boundary leads to the reduction in the ?{sub Hall}/?{sub opt} ratio as well as N{sub opt}. As a result, we find that the thickness dependence of the carrier transport properties is almost completely governed by the grain boundary formation. On the other hand, when the ZnO layer is exposed to wet air at 85?C, ?{sub Hall} reduces drastically with a minor variation of ?{sub opt} due to the enhanced grain boundary scattering. We have also characterized textured ZnO:Al layers prepared by HCl wet etching by SE. The analysis revealed that the near-surface carrier concentration increases slightly after the etching. We demonstrate that the SE technique can be applied to distinguish various rough textured structures (size???1??m) of the ZnO layers prepared by the HCl etching.

  15. NEAR-INFRARED DETECTION OF A SUPER-THIN DISK IN NGC 891

    SciTech Connect (OSTI)

    Schechtman-Rook, Andrew; Bershady, Matthew A.

    2013-08-10

    We probe the disk structure of the nearby, massive, edge-on spiral galaxy NGC 891 with subarcsecond resolution JHK{sub s}-band images covering {approx} {+-}10 kpc in radius and {+-}5 kpc in height. We measure intrinsic surface brightness (SB) profiles using realistic attenuation corrections constrained from near- and mid-infrared (Spitzer) color maps and three-dimensional Monte Carlo radiative-transfer models. In addition to the well-known thin and thick disks, a super-thin disk with 60-80 pc scale-height-comparable to the star-forming disk of the Milky Way-is visibly evident and required to fit the attenuation-corrected light distribution. Asymmetries in the super-thin disk light profile are indicative of young, hot stars producing regions of excess luminosity and bluer (attenuation-corrected) near-infrared color. To fit the inner regions of NGC 891, these disks must be truncated within {approx}3 kpc, with almost all their luminosity redistributed in a bar-like structure 50% thicker than the thin disk. There appears to be no classical bulge but rather a nuclear continuation of the super-thin disk. The super-thin, thin, thick, and bar components contribute roughly 30%, 42%, 13%, and 15% (respectively) to the total K{sub s}-band luminosity. Disk axial ratios (length/height) decrease from 30 to 3 from super-thin to thick components. Both exponential and sech{sup 2} vertical SB profiles fit the data equally well. We find that the super-thin disk is significantly brighter in the K{sub s}-band than typically assumed in integrated spectral energy distribution models of NGC 891: it appears that in these models the excess flux, likely produced by young stars in the super-thin disk, has been mistakenly attributed to the thin disk.

  16. Buildings Energy Data Book: 1.6 Embodied Energy of Building Assemblies

    Buildings Energy Data Book [EERE]

    7 Embodied Energy of Floor Structures in the U.S. Floor Structure with Interior Ceiling Finish of Gypsum Board, Latex Paint Embodied Energy CO2 Equivalent (MMBtu/SF) (1) Emissions (lbs/SF) Glulam joist and plank decking 0.04 3.06 Precast Hollowcore 0.05 13.43 Wood I-joist 0.02 2.03 Open-web Steel Joist 0.06 7.94 Open-web Steel Joist with concrete topping 0.07 12.30 Precast Double-T 0.04 11.38 Precast Double-T with concrete topping 0.06 16.45 Steel Joist 0.06 8.82 Steel Joist with plywood decking

  17. Transuranic waste characterization sampling and analysis plan

    SciTech Connect (OSTI)

    NONE

    1994-12-31

    Los Alamos National Laboratory (the Laboratory) is located approximately 25 miles northwest of Santa Fe, New Mexico, situated on the Pajarito Plateau. Technical Area 54 (TA-54), one of the Laboratory`s many technical areas, is a radioactive and hazardous waste management and disposal area located within the Laboratory`s boundaries. The purpose of this transuranic waste characterization, sampling, and analysis plan (CSAP) is to provide a methodology for identifying, characterizing, and sampling approximately 25,000 containers of transuranic waste stored at Pads 1, 2, and 4, Dome 48, and the Fiberglass Reinforced Plywood Box Dome at TA-54, Area G, of the Laboratory. Transuranic waste currently stored at Area G was generated primarily from research and development activities, processing and recovery operations, and decontamination and decommissioning projects. This document was created to facilitate compliance with several regulatory requirements and program drivers that are relevant to waste management at the Laboratory, including concerns of the New Mexico Environment Department.

  18. Final evaluation report for Lockheed Idaho Technologies Company, ARROW-PAK packaging, Docket 95-40-7A, Type A container

    SciTech Connect (OSTI)

    Kelly, D.L.

    1995-11-01

    The report documents the U.S. Department of Transportation Specification 7A Type A (DOT-7A) compliance test results of the ARROW-PAK packaging. The ARROW-PAK packaging system consists of Marlex M-8000 Driscopipe (Series 8000 [gas] or Series 8600 [industrial]) resin pipe, manufactured by Phillips-Driscopipe, Inc., and is sealed with two dome-shaped end caps manufactured from the same materials. The patented sealing process involves the use of electrical energy to heat opposing faces of the pipe and end caps, and hydraulic rams to press the heated surfaces together. This fusion process produces a homogeneous bonding of the end cap to the pipe. The packaging may be used with or without the two internal plywood spacers. This packaging was evaluated and tested in October 1995. The packaging configuration described in this report is designed to ship Type A quantities of solid radioactive materials, Form No. 1, Form No. 2, and Form No. 3.

  19. Test and evaluation report for Lockheed Idaho Technologies Company, arrow-pak packaging, docket 95-40-7A, type A container

    SciTech Connect (OSTI)

    Kelly, D.L.

    1996-03-14

    This report incorporates the U.S. Department of Energy, Office of Facility Safety Analysis (DOE/EH-32) approval letter for packaging use. This report documents the U.S. Department of Transportation Specification 7A Type A (DOT-7A) compliance test results of the Arrow-Pak packaging. The Arrow-Pak packaging system consists of Marlex M-8000 Driscopipe, manufactured by Phillips-Driscopipe, Inc., and is sealed with two dome-shaped end caps manufactured from the same materials. The patented sealing process involves the use of electrical energy to heat opposing faces of the pipe and end caps, and hydraulic rams to press the heated surfaces together. This fusion process produces a homogeneous bonding of the end cap to the pipe. The packaging may be used with or without the two internal plywood spacers. This packaging configuration described in this report is designed to ship Type A quantities of solid radioactive materials.

  20. Method for recovering and using lignin in adhesive resins by extracting demethylated lignin

    DOE Patents [OSTI]

    Schroeder, Herbert A.

    1991-01-01

    Lignin, or a lignin derived material, which has been significantly demethylated (e.g., the demethylated lignin found in the raffinate produced as a by-product of dimethyl sulfide production which can be carried out using the spent liquor from wood pulping operations) can be isolated by a process wherein an organic solvent is added to a lignin-containing aqueous solution. The organic solvent is typically a polar, and at least a partially water-immiscible substance such as, for example, ethyl acetate. The resulting lignin-containing aqueous solution/organic solvent mixture is acidified to produce a water layer which is discarded and an organic solvent layer which contains the demethylated lignin. Upon its recovery, the demethylated lignin is preferably dried and stored until it is used (along with an alkali, an aldehyde and an adhesive filler) in compounding an adhesive of the type generally used in the manufacture of plywood.