National Library of Energy BETA

Sample records for thick plywood roughly

  1. Effect of surface roughness on magnetic domain wall thickness, domain size, and coercivity

    E-Print Network [OSTI]

    Wang, Gwo-Ching

    , Rensselaer Polytechnic Institute, Troy, New York 12180-3590 G. Palasantzas and J. Th. M. De Hosson Department nm thick deposited on plasma etched Si 100 substrates showed that, by increasing surface rough- ness nearly linearly with film thickness. Such an increase of the thickness fluctuations5 was attributed

  2. Estimated Demand for Lumber and Plywood in Hawaii

    E-Print Network [OSTI]

    Estimated Demand for Lumber and Plywood in Hawaii by the Year 2000 George D. Frazier U S. FOREST for lumber and plywood in Hawaii by the year 2000. Berkeley, Calif., Pacific SW. Forest & Range Expt. Sta. 9 in Hawaii is expected to be between 78 and 128 million board feet. Hardwood lumber consumption is expected

  3. Wetting, Spreading, and Adsorption on Randomly Rough Surfaces

    E-Print Network [OSTI]

    S. Herminghaus

    2011-11-17

    The wetting properties of solid substrates with customary (i.e., macroscopic) random roughness are considered as a function of the microscopic contact angle of the wetting liquid and its partial pressure in the surrounding gas phase. Analytic expressions are derived which allow for any given lateral correlation function and height distribution of the roughness to calculate the wetting phase diagram, the adsorption isotherms, and to locate the percolation transition in the adsorbed liquid film. Most features turn out to depend only on a few key parameters of the roughness, which can be clearly identified. It is shown that a first order transition in the adsorbed film thickness, which we term 'Wenzel prewetting', occurs generically on typical roughness topographies, but is absent on purely Gaussian roughness. It is thereby shown that even subtle deviations from Gaussian roughness characteristics may be essential for correctly predicting even qualitative aspects of wetting.

  4. An Exploratory Study of the Use of Lumber, OSB, Plywood, LVL, PSL AND LSL As Raw Materials in the Furniture and Cabinet

    E-Print Network [OSTI]

    Wu, Qinglin

    An Exploratory Study of the Use of Lumber, OSB, Plywood, LVL, PSL AND LSL As Raw Materials in the manufacture of value-added wood products such as furniture, cabinets and millwork, other raw material inputs of the total value of raw materials used by respondents in 1999 was comprised of hardwood lumber followed

  5. Combinatorial Block Copolymer Ordering on Tunable Rough

    SciTech Connect (OSTI)

    Kulkarni M. M.; Yager K.; Sharma, A.; Karim, A.

    2012-05-01

    Morphology control of block copolymer (BCP) thin films through substrate interaction via controlled roughness parameters is of significant interest for numerous high-tech applications ranging from solar cells to high-density storage media. While effects of substrate surface energy (SE) and roughness (R) on BCP morphology have been individually investigated, their synergistic effects have not been explored in any systematic manner. Interestingly, orientation response of BCP to changes in SE can be similar to what can be accomplished with variations in R. Here we present a novel approach for orienting lamellar BCP films of poly(styrene)-block-poly(methyl methacrylate) (PS-PMMA) on spin-coated xerogel (a dried gel of silica nanoparticle network) substrate with simultaneously tunable surface energy, {gamma}{sub s} {approx} 29-53 mJ/m{sup 2}, by UVO exposure and roughness, R{sub rms} {approx} 0.5-30 nm, by sol-gel processing steps of regulating the catalyst concentration and sol aging time. As in previous BCP orientation studies on 20 nm diameter monodisperse silica nanoparticle coated surface, we find a similar but broadened oscillatory BCP orientation behavior with film thickness due to the random rather than periodic rough surfaces. We also find that higher random roughness amplitude is not the necessary criteria for obtaining a vertical orientation of BCP lamellae. Rather, a high surface fractal dimension (D{sub f} > 2.4) of the rough substrate in conjunction with an optimal substrate surface energy {gamma}{sub s} 29 mJ/m{sup 2} results in 100% vertically oriented lamellar microdomains. The AFM measured film surface microstructure correlates well with the internal 3D BCP film structure probed by grazing incidence small-angle X-ray scattering (GISAXS) and rotational small-angle neutron scattering (SANS). In contrast to tunable self-assembled monolayer (SAM)-coated substrates, the xerogel films are very durable and retain their chemical properties over period of several months. These results also highlight importantly that BCP orientation control for nanotechnology is possible not only on specially prepared patterned substrates but also on industrially viable sol-gel substrates.

  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. 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.

  9. Concentration of Eigenfunctions in Rough Media

    E-Print Network [OSTI]

    Smith, Hart F.

    Concentration of Eigenfunctions in Rough Media Hart F. Smith Department of Mathematics University of Washington, Seattle UC Irvine - June 18, 2012 Hart F. Smith Eigenfunctions in Rough Media #12;M = compact L2(M) (p) ( p 2 ) Hart F. Smith Eigenfunctions in Rough Media #12;M = compact manifold with volume

  10. 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.

  11. Water Dynamics at Rough Interfaces

    E-Print Network [OSTI]

    Markus Rosenstihl; Kerstin Kämpf; Felix Klameth; Matthias Sattig; Michael Vogel

    2014-07-21

    We use molecular dynamics computer simulations and nuclear magnetic resonance experiments to investigate the dynamics of water at interfaces of molecular roughness and low mobility. We find that, when approaching such interfaces, the structural relaxation of water, i.e., the $\\alpha$ process, slows down even when specific attractive interactions are absent. This prominent effect is accompanied by a smooth transition from Vogel to Arrhenius temperature dependence and by a growing importance of jump events. Consistently, at protein surfaces, deviations from Arrhenius behavior are weak when free water does not exist. Furthermore, in nanoporous silica, a dynamic crossover of liquid water occurs when a fraction of solid water forms near 225 K and, hence, the liquid dynamics changes from bulk-like to interface-dominated. At sufficiently low temperatures, water exhibits a quasi-universal $\\beta$ process, which is characterized by an activation energy of $E_a\\!=\\!0.5$ eV and involves anisotropic reorientation about large angles. As a consequence of its large amplitude, the faster $\\beta$ process destroys essentially all orientational correlation, rendering observation of a possible slower $\\alpha$ process difficult in standard experiments. Nevertheless, we find indications for the existence of structural relaxation down to a glass transition of interfacial water near 185 K. Hydrated proteins show a highly restricted backbone motion with an amplitude, which decreases upon cooling and vanishes at comparable temperatures, providing evidence for a high relevance of water rearrangements in the hydration shell for secondary protein relaxations.

  12. Interfacial Friction in Gas-Liquid Annular Flow: Analogies to Full and Transition Roughness

    SciTech Connect (OSTI)

    Bauer, R.C.; Beus, S.G.; Fore, L.B.

    1999-03-01

    New film thickness and pressure gradient data were obtained in a 5.08 by 101.6 mm duct for nitrogen and water in annular flow. Pressures of 3.4 and 17 atm and temperatures of 38 and 93 C were used to vary the gas density and liquid viscosity. These data are used to compute interfacial shear stresses and interfacial friction factors for comparison with several accepted literature correlations. These comparisons are reasonable for small values of the relative film thickness. However, the new data cover conditions not approached by the data used to construct those correlations. By combining the current data with the results of two other comprehensive modern experimental studies, a new correlation for the interfacial friction factor has been developed. This correlation adds elements of transition roughness to Wallis' fully-rough analogy to better predict interfacial friction factors over a wide range of gas Reynolds numbers and liquid film thicknesses.

  13. Combinatorial Block Copolymer Ordering on Tunable Rough Substrates

    SciTech Connect (OSTI)

    Kulkarni, Manish M.; Yager, Kevin G.; Sharma, Ashutosh; Karim, Alamgir (IIT-India); (Akron); (BNL)

    2012-10-25

    Morphology control of block copolymer (BCP) thin films through substrate interaction via controlled roughness parameters is of significant interest for numerous high-tech applications ranging from solar cells to high-density storage media. While effects of substrate surface energy (SE) and roughness (R) on BCP morphology have been individually investigated, their synergistic effects have not been explored in any systematic manner. Interestingly, orientation response of BCP to changes in SE can be similar to what can be accomplished with variations in R. Here we present a novel approach for orienting lamellar BCP films of poly(styrene)-block-poly(methyl methacrylate) (PS-PMMA) on spin-coated xerogel (a dried gel of silica nanoparticle network) substrate with simultaneously tunable surface energy, {gamma}{sub s} {approx} 29-53 mJ/m{sup 2}, by UVO exposure and roughness, R{sub rms} {approx} 0.5-30 nm, by sol-gel processing steps of regulating the catalyst concentration and sol aging time. As in previous BCP orientation studies on 20 nm diameter monodisperse silica nanoparticle coated surface, we find a similar but broadened oscillatory BCP orientation behavior with film thickness due to the random rather than periodic rough surfaces. We also find that higher random roughness amplitude is not the necessary criteria for obtaining a vertical orientation of BCP lamellae. Rather, a high surface fractal dimension (D{sub f} > 2.4) of the rough substrate in conjunction with an optimal substrate surface energy {gamma}{sub s} {approx} 29 mJ/m{sup 2} results in 100% vertically oriented lamellar microdomains. The AFM measured film surface microstructure correlates well with the internal 3D BCP film structure probed by grazing incidence small-angle X-ray scattering (GISAXS) and rotational small-angle neutron scattering (SANS). In contrast to tunable self-assembled monolayer (SAM)-coated substrates, the xerogel films are very durable and retain their chemical properties over period of several months. These results also highlight importantly that BCP orientation control for nanotechnology is possible not only on specially prepared patterned substrates but also on industrially viable sol-gel substrates.

  14. 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.

  15. Critical thickness in silicone thermosets

    E-Print Network [OSTI]

    Deopura, Manish, 1975-

    2005-01-01

    Critical thickness effects are utilized to achieve high fracture toughness in brittle polymers. The postulate of critical thickness, which is: "Macroscopically brittle polymers deform in a ductile fashion below a critical ...

  16. A CONSTRUCTION OF THE ROUGH PATH ABOVE FRACTIONAL ...

    E-Print Network [OSTI]

    2013-03-05

    Appl. 120 (2010) 1444–1472], where the construction of a rough path over B was first introduced. 1. Introduction. Rough paths analysis is a theory introduced by ...

  17. Flow rule of dense granular flows down a rough incline

    E-Print Network [OSTI]

    Tamas Borzsonyi; Robert E. Ecke

    2007-07-09

    We present experimental findings on the flow rule for granular flows on a rough inclined plane using various materials including sand and glass beads of various sizes and four types of copper particles with different shapes. We characterize the materials by measuring $h_s$ (the thickness at which the flow subsides) as a function of the plane inclination $\\theta$ on various surfaces. Measuring the surface velocity $u$ of the flow as a function of flow thickness $h$, we find that for sand and glass beads the Pouliquen flow rule $u/\\sqrt{gh} \\sim \\beta h/h_s$ provides reasonable but not perfect collapse of the $u(h)$ curves measured for various $\\theta$ and mean particle diameter $d$. Improved collapse is obtained for sand and glass beads by using a recently proposed scaling of the form $u/\\sqrt{gh} =\\beta \\cdot h \\tan^2\\theta /h_s\\ \\tan^2\\theta_1$ where $\\theta_1$ is the angle at which the $h_s(\\theta)$ curves diverge. Measuring the slope $\\beta$ for ten different sizes of sand and glass beads, we find a systematic, strong increase of $\\beta$ with the divergence angle $\\theta_1$ of $h_s$. The copper materials with different shapes are not well described by either flow rule with $u \\sim h^{3/2}$.

  18. Measuring Thickness Changes in Thin Films Due to Chemical Reaction by Monitoring the Surface

    E-Print Network [OSTI]

    Rutenberg, Andrew

    to the study of lithium-ion batteries. Recently metallic alloys M ~M Si, Sn, Al, etc.! have been proposed force microscope, expansion and contraction, Li-ion battery, surface roughness, thin film thickness as possible negative electrode materials for lithium-ion bat- teries ~Yang et al., 1996; Idota et al., 1997

  19. Correlating toughness and roughness in ductile fracture

    E-Print Network [OSTI]

    Ponson, Laurent; Osovski, Shmulik; Bouchaud, Elisabeth; Tvergaard, Viggo; Needleman, Alan

    2013-01-01

    Three dimensional calculations of ductile crack growth under mode I plane strain, small scale yielding conditions are carried out using an elastic-viscoplastic constitutive relation for a progres- sively cavitating plastic solid with two populations of void nucleating second phase particles. Full field solutions are obtained for three dimensional material microstructures characterized by ran- dom distributions of void nucleating particles. Crack growth resistance curves and fracture surface roughness statistics are calculated using standard procedures. The range of void nucleating particle volume fractions considered give rise to values of toughness, JIC, that vary by a factor of four. For all volume fractions considered, the computed fracture surfaces are self-affine over a size range of about two orders of magnitude with a roughness exponent of 0.54 $\\pm$ 0.03. For small void nucleating particle volume fractions, the mean large particle spacing serves as a single dominant length scale. In this regime, the c...

  20. 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.

  1. Correlating toughness and roughness in ductile fracture

    E-Print Network [OSTI]

    Laurent Ponson; Ankit Srivastava; Shmulik Osovski; Elisabeth Bouchaud; Viggo Tvergaard; Alan Needleman

    2013-07-16

    Three dimensional calculations of ductile crack growth under mode I plane strain, small scale yielding conditions are carried out using an elastic-viscoplastic constitutive relation for a progres- sively cavitating plastic solid with two populations of void nucleating second phase particles. Full field solutions are obtained for three dimensional material microstructures characterized by ran- dom distributions of void nucleating particles. Crack growth resistance curves and fracture surface roughness statistics are calculated using standard procedures. The range of void nucleating particle volume fractions considered give rise to values of toughness, JIC, that vary by a factor of four. For all volume fractions considered, the computed fracture surfaces are self-affine over a size range of about two orders of magnitude with a roughness exponent of 0.54 $\\pm$ 0.03. For small void nucleating particle volume fractions, the mean large particle spacing serves as a single dominant length scale. In this regime, the correlation length of the fracture surface corresponding to the cut-off of the self-affine behavior is found to be linearly related to JIC thus quantitatively correlating toughness and fracture surface roughness.

  2. Distributed Roughness Receptivity in a Flat Plate Boundary Layer 

    E-Print Network [OSTI]

    Kuester, Matthew Scott

    2014-04-18

    the incoming boundary layer. This dissertation describes an experiment specifically designed to study the shielding effect. Three roughness configurations, a deterministic distributed roughness patch, a slanted rectangle, and the combination of the two, were...

  3. A fast direct numerical simulation method for characterising hydraulic roughness

    E-Print Network [OSTI]

    Chung, Daniel; MacDonald, Michael; Hutchins, Nicholas; Ooi, Andrew

    2015-01-01

    We describe a fast direct numerical simulation (DNS) method that promises to directly characterise the hydraulic roughness of any given rough surface, from the hydraulically smooth to the fully rough regime. The method circumvents the unfavourable computational cost associated with simulating high-Reynolds-number flows by employing minimal-span channels (Jimenez & Moin 1991). Proof-of-concept simulations demonstrate that flows in minimal-span channels are sufficient for capturing the downward velocity shift, that is, the Hama roughness function, predicted by flows in full-span channels. We consider two sets of simulations, first with modelled roughness imposed by body forces, and second with explicit roughness described by roughness-conforming grids. Owing to the minimal cost, we are able to conduct DNSs with increasing roughness Reynolds numbers while maintaining a fixed blockage ratio, as is typical in full-scale applications. The present method promises a practical, fast and accurate tool for character...

  4. Adhesive rough contacts near complete contact

    E-Print Network [OSTI]

    M. Ciavarella

    2015-05-01

    Recently, there has been some debate over the effect of adhesion on the contact of rough surfaces. Classical asperity theories predict, in agreement with experimental observations, that adhesion is always destroyed by roughness except if the amplitude of the same is extremely small, and the materials are particularly soft. This happens for all fractal dimensions. However, these theories are limited due to the geometrical simplification, which may be particularly strong in conditions near full contact. We introduce therefore a simple model for adhesion, which aims at being rigorous near full contact, where we postulate there are only small isolated gaps between the two bodies. The gaps can be considered as "pressurized cracks" by using Ken Johnson's idea of searching a corrective solution to the full contact solution. The solution is an extension of the adhesive-less solution proposed recently by Xu, Jackson, and Marghitu (XJM model) (2014). This process seems to confirm recent theories using the JKR theory, namely that the effect of adhesion depends critically on the fractal dimension. For D2.5, seems for large enough magnifications that a full fractal roughness completely destroys adhesion. These results are partly paradoxical since strong adhesion is not observed in nature except in special cases. A possible way out of the paradox may be that the conclusion is relevant for the near full contact regime, where the strong role of flaws at the interfaces, and of gaps full of contaminant, trapped air or liquid in pressure, needs to be further explored. If conditions near full contact are not achieved on loading, probably the conclusions of classical asperity theories may be confirmed.

  5. System for measuring film thickness

    DOE Patents [OSTI]

    Batishko, Charles R. (West Richland, WA); Kirihara, Leslie J. (Richland, WA); Peters, Timothy J. (Richland, WA); Rasmussen, Donald E. (Richland, WA)

    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.

  6. Hydrothermal coupling in a rough fracture

    E-Print Network [OSTI]

    Neuville, A; Schmittbuhl, J; Neuville, Am\\'{e}lie; Toussaint, Renaud; Schmittbuhl, Jean

    2006-01-01

    Heat exchange during laminar flow is studied at the fracture scale on the basis of the Stokes equation. We used a synthetic aperture model (a self-affine model) that has been shown to be a realistic geometrical description of the fracture morphology. We developed a numerical modelling using a finite difference scheme of the hydrodynamic flow and its coupling with an advection/conduction description of the fluid heat. As a first step, temperature within the surrounding rock is supposed to be constant. Influence of the fracture roughness on the heat flux through the wall, is estimated and a thermalization length is shown to emerge. Implications for the Soultz-sous-For\\^{e}ts geothermal project are discussed.

  7. 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 [S.A. Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation)

    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)

  8. Lamellar Diblock Copolymers on Rough Substrates: Self-consistent Field Theory Studies

    E-Print Network [OSTI]

    Xingkun Man; Jiuzhou Tang; Pan Zhou; Dadong Yan; David Andelman

    2015-08-18

    We present numerical calculations of lamellar phases of di-block copolymers (BCP) confined between two surfaces, where the top surface is flat and the bottom one is corrugated. The corrugated substrate is assumed to have a single $q$-mode of lateral undulations with a wavenumber q_s and amplitude R. We focus on the effects of substrate roughness, parameterized by the dimensionless quantity, q_sR, on the relative stability between parallel and perpendicular orientations of the lamellar phase. The competition between film confinement, energy cost of elastic deformation and gain in surface energy induces a parallel-to-perpendicular transition of the BCP lamellae. Employing self-consistent field theory (SCFT), we study the critical substrate roughness value corresponding to this transition. The critical value increases as function of the surface preference towards one of the two BCP components, and as function of film thickness. But, it decreases with increasing values of the Flory-Huggins parameter. Our findings are equivalent to stating that the critical value decreases as the BCP molecular weight or the natural BCP periodicity increases. We further show that the rough substrate can overcome the formation of parallel lamellae in cases where the top surface has a preference towards one of the two BCP components. Our results are in good agreement with previous experiments, and highlight the physical conditions behind the perpendicular orientation of lamellar phases, as is desired in nanolithography and other industrial applications.

  9. Enhanced Tissue Adhesion by Increased Porosity and Surface Roughness...

    Office of Scientific and Technical Information (OSTI)

    Enhanced Tissue Adhesion by Increased Porosity and Surface Roughness of Carbon Based Biomaterials Citation Details In-Document Search Title: Enhanced Tissue Adhesion by Increased...

  10. CHARACTERIZATION OF SURFACE ROUGHNESS AND INITIAL CONDITIONS FOR CYLINDRICAL HYDRODYNAMIC

    E-Print Network [OSTI]

    Barnes, Cris W.

    CHARACTERIZATION OF SURFACE ROUGHNESS AND INITIAL CONDITIONS FOR CYLINDRICAL HYDRODYNAMIC AND MIX across a variable density interface, that interface must be well characterized. There exist a number, characterizing, and affecting the surface roughness was driven by Ablative Rayleigh-Taylor work5

  11. 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.

  12. Gravitational quantum states of neutrons in a rough waveguide

    E-Print Network [OSTI]

    A. E. Meyerovich; V. V. Nesvizhevsky

    2006-03-22

    A theory of gravitational quantum states of ultracold neutrons in waveguides with absorbing/scattering walls is presented. The theory covers recent experiments in which the ultracold neutrons were beamed between a mirror and a rough scatterer/absorber. The analysis is based on a recently developed theory of quantum transport along random rough walls which is modified in order to include leaky (absorbing) interfaces and, more importantly, the low-amplitude high-aperture roughness. The calculations are focused on a regime when the direct transitions into the continuous spectrum above the absorption threshold dominate the depletion of neutrons from the gravitational states and are more efficient than the processes involving the intermediate states. The theoretical results for the neutron count are sensitive to the correlation radius (lateral size) of surface inhomogeneities and to the ratio of the particle energy to the absorption threshold in a weak roughness limit. The main impediment for observation of the higher gravitational states is the "overhang" of the particle wave functions which can be overcome only by use scatterers with strong roughness. In general, the strong roughness with high amplitude is preferable if one wants just to detect the individual gravitational states, while the strong roughness experiments with small amplitude and high aperture are preferable for the quantitative analysis of the data. We also discuss the ways to further improve the accuracy of calculations and to optimize the experimental regime.

  13. Wetting on Random Roughness: the Ubiquity of Wenzel Prewetting

    E-Print Network [OSTI]

    Stephan Herminghaus

    2012-03-23

    The wetting properties of solid substrates with macroscopic random roughness are considered as a function of the microscopic contact angle of the wetting liquid and its partial pressure in the surrounding gas phase. It is shown that Wenzel prewetting, which has been recently predicted for a rather wide class of roughness pro?les derived from Gaussian random processes by a general distortion procedure, should in fact be ubiquitous and prevail under even much milder conditions. The well-known transition occurring at Wenzel's angle is accompanied by a prewetting transition, at which a jump in the adsorbed liquid volume occurs. This should be present on most surfaces bearing homogeneous, isotropic random roughness.

  14. 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 2–27 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.

  15. Influence of surface roughness and waviness upon thermal contact resistance

    E-Print Network [OSTI]

    Yovanovich, M. Michael

    1967-01-01

    This work deals with the phenomenon of thermal resistance between contacting solids. Attention is directed towards contiguous solids possessing both surface roughness and waviness. When two such surfaces are brought together ...

  16. Effect of Surface Roughness on Wind Turbine Performance 

    E-Print Network [OSTI]

    Ehrmann, Robert Schaefer

    2014-06-25

    Wind farm operators observe production deficits as machines age. Quantifying deterioration on individual components is difficult, but one potential explanation is accumulation of blade surface roughness. Historically, wind turbine airfoils were...

  17. PROPAGATION OF SINGULARITIES FOR ROUGH METRICS HART F. SMITH

    E-Print Network [OSTI]

    Smith, Hart F.

    PROPAGATION OF SINGULARITIES FOR ROUGH METRICS HART F. SMITH Abstract. We use a wave packet the Simons Foundation (# 266371 to Hart Smith). 1 #12;2 HART F. SMITH H¨ormander's theorem [9] on propagation

  18. Hypersonic Measurements of Roughness-Induced Transient Growth 

    E-Print Network [OSTI]

    Sharp, Nicole Susanne

    2014-04-17

    The effects of surface roughness on boundary-layer disturbance growth and laminar-to-turbulent transition are not well understood, especially in hypersonic boundary layers. The transient growth mechanism that produces algebraic growth of stream wise...

  19. The apparent roughness of a sand surface blown by wind from an analytical model of saltation

    E-Print Network [OSTI]

    Thomas Pähtz; Jasper F. Kok; Hans J. Herrmann

    2015-03-16

    We present an analytical model of aeolian sand transport. The model quantifies the momentum transfer from the wind to the transported sand by providing expressions for the thickness of the saltation layer and the apparent surface roughness. These expressions are derived from basic physical principles and a small number of assumptions. The model further predicts the sand transport rate (mass flux) and the impact threshold (the smallest value of the wind shear velocity at which saltation can be sustained). We show that, in contrast to previous studies, the present model's predictions are in very good agreement with a range of experiments, as well as with numerical simulations of aeolian saltation. Because of its physical basis, we anticipate that our model will find application in studies of aeolian sand transport on both Earth and Mars.

  20. Sept 2001 Rough Draft OFFM Policy Letter 02-1.doc | Department...

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

    Sept 2001 Rough Draft OFFM Policy Letter 02-1.doc Sept 2001 Rough Draft OFFM Policy Letter 02-1.doc Sept 2001 Rough Draft OFFM Policy Letter 02-1.doc More Documents & Publications...

  1. Ice thickness measurements by Raman scattering

    E-Print Network [OSTI]

    Pershin, Sergey M; Klinkov, Vladimir K; Yulmetov, Renat N; Bunkin, Alexey F

    2014-01-01

    A compact Raman LIDAR system with a spectrograph was used for express ice thickness measurements. The difference between the Raman spectra of ice and liquid water is employed to locate the ice-water interface while elastic scattering was used for air-ice surface detection. This approach yields an error of only 2 mm for an 80-mm-thick ice sample, indicating that it is promising express noncontact thickness measurements technique in field experiments.

  2. Surface and Interface Properties of 10–12 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 (?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 phasemore »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. 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

    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 ( ? 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, latticemore »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

  4. Application of Rough Set Theory to Analysis of Hydrocyclone Operation

    E-Print Network [OSTI]

    Owladeghaffari, H; Irannajad, M

    2008-01-01

    This paper describes application of rough set theory, on the analysis of hydrocyclone operation. In this manner, using Self Organizing Map (SOM) as preprocessing step, best crisp granules of data are obtained. Then, using a combining of SOM and rough set theory (RST)-called SORST-, the dominant rules on the information table, obtained from laboratory tests, are extracted. Based on these rules, an approximate estimation on decision attribute is fulfilled. Finally, a brief comparison of this method with the SOM-NFIS system (briefly SONFIS) is highlighted.

  5. E ective boundary conditions for laminar ows over periodic rough boundaries

    E-Print Network [OSTI]

    Achdou, Yves

    E#27;ective boundary conditions for laminar #29;ows over periodic rough boundaries Yves Achdou #3 are proposed for a laminar #29;ow over a rough wall with periodic roughness elements. These e#27;ective is such an approach ? In this paper, we wish to answer these questions for laminar #29;ows over periodic rough walls

  6. 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.

  7. ORIGINAL PAPER Transient Heat Conduction Between Rough Sliding Surfaces

    E-Print Network [OSTI]

    Awtar, Shorya

    , and the results are combined with the height distributions to determine the mean heat flux and the mean normal increases with the square root of the sliding speed and decreases with the 3/4 power of the combined RMSORIGINAL PAPER Transient Heat Conduction Between Rough Sliding Surfaces Yuwei Liu · J. R. Barber

  8. Analysis of the Scattering by an Unbounded Rough Surface

    E-Print Network [OSTI]

    2011-11-12

    eling acoustic and electromagnetic wave propagation over outdoor ground and sea surfaces, optical scattering from the ... been intensively examined by researchers in the engineering community. ..... explicit characterization of the norm in H1(?) via Fourier coefficient: ...... rough surfaces, Wave Motion, 24 (1996)

  9. LARGE EDDY SIMULATION OF TURBULENT BOUNDARY LAYERS OVER ROUGH BEDS

    E-Print Network [OSTI]

    Pawlak, Geno

    that determines the response of the boundary layer is not clear. One method to characterize the irregular nature with different spectral slopes using 2D 10 % loading square waves as basis functions. These square waves can) is then used to simulate the turbulent boundary layer over the rough beds. The LES solver is first validated

  10. Ultrasonic thickness testing of aging offshore structures 

    E-Print Network [OSTI]

    Ellison, Brian Kirk

    1999-01-01

    The objectives of this thesis concern the use of ultrasonic thickness (UT) testing for use in the offshore industry. Evidence from prior studies conducted at Texas A&M University suggests that the corrosion on the surface ...

  11. MonolayerThickness of Block Copolymer Films

    E-Print Network [OSTI]

    Petta, Jason

    .47 · Index of ref. for PS-PEHMA 1.51 #12;Annealing the films · Tg 22nm 24nm Height Images #12;AFM 12-33 26nm 28nm 30nm Bi-continuous #12;12-33Area% 13.08 31.55 41 Area % Thickness (nm) Monolayer: 18.86nm Bilayer: 37.72nm #12;Monolayer thickness 12

  12. 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.

  13. Heat transfer between elastic solids with randomly rough surfaces

    E-Print Network [OSTI]

    B. N. J. Persson; B. Lorenz; A. I. Volokitin

    2009-08-27

    We study the heat transfer between elastic solids with randomly rough surfaces. We include both the heat transfer from the area of real contact, and the heat transfer between the surfaces in the noncontact regions. We apply a recently developed contact mechanics theory, which accounts for the hierarchical nature of the contact between solids with roughness on many different length scales. For elastic contact, at the highest (atomic) resolution the area of real contact typically consists of atomic (nanometer) sized regions, and we discuss the implications of this for the heat transfer. For solids with very smooth surfaces, as is typical in many modern engineering applications, the interfacial separation in the non-contact regions will be very small, and for this case we show the importance of the radiative heat transfer associated with the evanescent electromagnetic waves which exist outside of all bodies.

  14. Capillary adhesion between elastic solids with randomly rough surfaces

    E-Print Network [OSTI]

    B. N. J. Persson

    2008-05-06

    I study how the contact area and the work of adhesion, between two elastic solids with randomly rough surfaces, depend on the relative humidity. The surfaces are assumed to be hydrophilic, and capillary bridges form at the interface between the solids. For elastically hard solids with relative smooth surfaces, the area of real contact and therefore also the sliding friction, are maximal when there is just enough liquid to fill out the interfacial space between the solids, which typically occurs for $d_{\\rm K} \\approx 3 h_{\\rm rms}$, where $d_{\\rm K}$ is the height of the capillary bridge and $h_{\\rm rms}$ the root-mean-square roughness of the (combined) surface roughness profile. For elastically soft solids, the area of real contact is maximal for very low humidity (i.e., small $d_{\\rm K}$), where the capillary bridges are able to pull the solids into nearly complete contact. In both case, the work of adhesion is maximal (and equal to $2\\gamma {\\rm cos}\\theta$, where $\\gamma$ is the liquid surface tension and $\\theta$ the liquid-solid contact angle) when $d_{\\rm K} >> h_{\\rm rms}$, corresponding to high relative humidity.

  15. Pd conductor for thick film hydrogen sensor

    SciTech Connect (OSTI)

    Felten, J.J. [DuPont Electronics, Research Triangle Park, NC (United States); Hoffheins, B.S.; Lauf, R.J. [Oak Ridge National Lab., TN (United States)

    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.

  16. 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.

  17. Gas turbine bucket wall thickness control

    DOE Patents [OSTI]

    Stathopoulos, Dimitrios (Glenmont, NY); Xu, Liming (Greenville, SC); Lewis, Doyle C. (Greer, SC)

    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.

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

    Office of Scientific and Technical Information (OSTI)

    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...

  19. Free Energy of thick Center Vortices

    E-Print Network [OSTI]

    Ch. Korn; H. Reinhardt; T. Tok

    2005-08-05

    The free energy of thick center vortices is calculated in continuum Yang-Mills theory in one-loop approximation using the proper time regularization. The vortices are represented by Abelian gauge field configurations on the torus which satisfy twisted boundary conditions.

  20. Thick beryllium coatings by magnetron sputtering

    SciTech Connect (OSTI)

    Wu, H; Nikroo, A; Youngblood, K; Moreno, K; Wu, D; Fuller, T; Alford, C; Hayes, J; Detor, A; Wong, M; Hamza, A; van Buuren, T; Chason, E

    2011-04-14

    Thick (>150 {micro}m) beryllium coatings are studied as an ablator material of interest for fusion fuel capsules for the National Ignition Facility (NIF). As an added complication, the coatings are deposited on mm-scale spherical substrates, as opposed to flats. DC magnetron sputtering is used because of the relative controllability of the processing temperature and energy of the deposits. We used ultra small angle x-ray spectroscopy (USAXS) to characterize the void fraction and distribution along the spherical surface. We investigated the void structure using a combination focused ion beam (FIB) and scanning electron microscope (SEM), along with transmission electron microscopy (TEM). Our results show a few volume percent of voids and a typical void diameter of less than two hundred nanometers. Understanding how the stresses in the deposited material develop with thickness is important so that we can minimize film cracking and delamination. To that end, an in-situ multiple optical beam stress sensor (MOSS) was used to measure the stress behavior of thick Beryllium coatings on flat substrates as the material was being deposited. We will show how the film stress saturates with thickness and changes with pressure.

  1. Effects of hydraulic roughness on surface textures of gravel-bed rivers

    E-Print Network [OSTI]

    Montgomery, David R.

    Effects of hydraulic roughness on surface textures of gravel-bed rivers John M. Buffington1 that bed-surface grain size is responsive to hydraulic roughness caused by bank irregularities, bars condition of low hydraulic roughness. For a given 0bf , channels with progressively greater hydraulic

  2. Independent External Peer Review Report Rough River Dam 18 August 2011 ii

    E-Print Network [OSTI]

    US Army Corps of Engineers

    #12;Independent External Peer Review Report ­ Rough River Dam 18 August 2011 ii This page intentionally blank. #12;Independent External Peer Review Report ­ Rough River Dam 18 August 2011 iii Table Panel Members B-1 Appendix C ­ Charge for IEPR Panel C-1 List of Figures Figure 1. Rough River Dam 4

  3. Scaling laws governing the roughness of the swash edge line

    E-Print Network [OSTI]

    Ed. Bormashenko; A. Musin; R. Grynuov

    2014-02-23

    The physics of swash i.e. a layer of water that washes up on the beach after an incoming wave has broken is complicated and intriguing. It includes perplexed hydrodynamic and sediment transport events. In our paper we address to the roughness of the moving swash boundary at which a beach, water and air meet. We treat the behavior of this boundary as an interfacial phenomenon, without going into details of formation of edge waves and beach cusps, covered broadly in literature. This "crude" approach turns out to be productive and revealing the resemblance of the swash line with a broad diversity of effects arising from the random pinning of moving boundaries.

  4. Scaling laws governing the roughness of the swash edge line

    E-Print Network [OSTI]

    Bormashenko, Ed; Grynuov, R

    2014-01-01

    The physics of swash i.e. a layer of water that washes up on the beach after an incoming wave has broken is complicated and intriguing. It includes perplexed hydrodynamic and sediment transport events. In our paper we address to the roughness of the moving swash boundary at which a beach, water and air meet. We treat the behavior of this boundary as an interfacial phenomenon, without going into details of formation of edge waves and beach cusps, covered broadly in literature. This "crude" approach turns out to be productive and revealing the resemblance of the swash line with a broad diversity of effects arising from the random pinning of moving boundaries.

  5. File:Wind rough example.pdf | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoopButtePowerEdistoWhiskey flats 100k.pdf Jump to: navigation, searchWind rough

  6. Strain relaxation of thick (11–22) semipolar InGaN layer for long wavelength nitride-based device

    SciTech Connect (OSTI)

    Kim, Jaehwan; Min, Daehong; Jang, Jongjin; Lee, Kyuseung; Chae, Sooryong; Nam, Okhyun, E-mail: ohnam@kpu.ac.kr [Advanced Photonics Research Center/LED Technology Center, Department of Nano-Optical Engineering, Korea Polytechnic University, 237, Sangidaehak-ro, Siheung-si, Gyeonggi-do 429-793 (Korea, Republic of)

    2014-10-28

    In this study, the properties of thick stress-relaxed (11–22) semipolar InGaN layers were investigated. Owing to the inclination of growth orientation, misfit dislocations (MDs) occurred at the heterointerface when the strain state of the (11–22) semipolar InGaN layers reached the critical point. We found that unlike InGaN layers based on polar and nonpolar growth orientations, the surface morphologies of the stress-relaxed (11–22) semipolar InGaN layers did not differ from each other and were similar to the morphology of the underlying GaN layer. In addition, misfit strain across the whole InGaN layer was gradually relaxed by MD formation at the heterointerface. To minimize the effect of surface roughness and defects in GaN layers on the InGaN layer, we conducted further investigation on a thick (11–22) semipolar InGaN layer grown on an epitaxial lateral overgrown GaN template. We found that the lateral indium composition across the whole stress-relaxed InGaN layer was almost uniform. Therefore, thick stress-relaxed (11–22) semipolar InGaN layers are suitable candidates for use as underlying layers in long-wavelength devices, as they can be used to control strain accumulation in the heterostructure active region without additional influence of surface roughness.

  7. Thickness-dependent secondary structure formation of tubelike polymers

    E-Print Network [OSTI]

    Janke, Wolfhard

    OFFPRINT Thickness-dependent secondary structure formation of tubelike polymers T. Vogel, T.epljournal.org doi: 10.1209/0295-5075/85/10003 Thickness-dependent secondary structure formation of tubelike polymers the conformational phase diagram of a simple model for flexible polymers with explicit thickness. The thickness

  8. Semiclassical Theory of Integrable and Rough Andreev Billiards

    E-Print Network [OSTI]

    W. Ihra; M. Leadbeater; J. L. Vega; K. Richter

    1999-09-08

    We study the effect on the density of states in mesoscopic ballistic billiards to which a superconducting lead is attached. The expression for the density of states is derived in the semiclassical S-matrix formalism shedding insight into the origin of the differences between the semiclassical theory and the corresponding result derived from random matrix models. Applications to a square billiard geometry and billiards with boundary roughness are discussed. The saturation of the quasiparticle excitation spectrum is related to the classical dynamics of the billiard. The influence of weak magnetic fields on the proximity effect in rough Andreev billiards is discussed and an analytical formula is derived. The semiclassical theory provides an interpretation for the suppression of the proximity effect in the presence of magnetic fields as a coherence effect of time reversed trajectories, similar to the weak localisation correction of the magneto-resistance in chaotic mesoscopic systems. The semiclassical theory is shown to be in good agreement with quantum mechanical calculations.

  9. Local contact stress measurements at a rough interface

    E-Print Network [OSTI]

    J. Scheibert; A. Prevost; J. Frelat; P. Rey; G. Debrégeas

    2007-11-07

    An original MEMS-based force sensing device is designed which allows to measure spatially resolved normal and tangential stress fields at the base of an elastomeric film. This device is used for the study of the contact stress between a rough film and a smooth glass sphere under normal load. The measured profiles are compared to Finite Elements Method calculations for a smooth contact with boundary conditions obeying Amontons-Coulomb's friction law. The accuracy of the measurements allows to discriminate between dry and lubricated contact conditions and to evidence load-dependent deviations from Amontons-Coulomb's profiles. These deviations are qualitatively interpreted by taking into account the finite compliance of the micro-contact population.

  10. A rough analytic relation on partial differential equations

    E-Print Network [OSTI]

    Kato, Tsuyoshi

    2010-01-01

    We introduce some analytic relations on the set of partial differential equations of two variables. It relies on a new comparison method to give rough asymptotic estimates for solutions which obey different partial differential equations. It uses a kind of scale transform called tropical geometry which connects automata with real rational dynamics. Two different solutions can be considered when their defining equations are transformed to the same automata at infinity. We have a systematic way to construct related pairs of different partial differential equations, and also construct some unrelated pairs concretely. These verify that the new relations are non trivial. We also make numerical calculations and compare the results for both related and unrelated pairs of PDEs.

  11. 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.

  12. Thermodynamics of sustaining gases in the roughness of submerged superhydrophobic surfaces

    E-Print Network [OSTI]

    Neelesh A. Patankar

    2015-05-22

    Rough surfaces submerged in a liquid can remain almost dry if the liquid does not fully wet the roughness and gases are sustained in roughness grooves. Such partially dry surfaces can help reduce drag or enhance boiling. Gases sustained in roughness grooves would be composed of air and the vapor phase of the liquid itself. The thermodynamics of sustaining vapor was considered in a prior work [Patankar, Soft Matter, 2010, 6:1613]. Here, the thermodynamics of sustaining gases (e.g. air) is considered. Governing equations are presented along with a solution methodology to determine a critical condition to sustain gases. The critical roughness scale to sustain gases is estimated for different degrees of saturation of gases dissolved in the liquid. It is shown that roughness spacings of less than a micron are essential to sustain gases on surfaces submerged in water at atmospheric pressure. This is consistent with prior empirical data.

  13. 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.

  14. Radiation phantom with humanoid shape and adjustable thickness

    DOE Patents [OSTI]

    Lehmann, Joerg (Pleasanton, CA); Levy, Joshua (Salem, NY); Stern, Robin L. (Lodi, CA); Siantar, Christine Hartmann (Livermore, CA); Goldberg, Zelanna (Carmichael, CA)

    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.

  15. Surface Roughness of Stainless Steel Bender Mirrors for Focusing Soft X-rays

    E-Print Network [OSTI]

    2005-01-01

    Surface Roughness of Stainless Steel Bender Mirrors forWe have used polished stainless steel as a mirror substratefor smooth polishing. Stainless steel is stronger and can be

  16. A Heat Kernel based Cortical Thickness Estimation Algorithm

    E-Print Network [OSTI]

    Wang, Yalin

    thickness, Heat Kernel, Tetrahedral Mesh, Streamline, False Discovery Rate 1 Introduction AlzheimerA Heat Kernel based Cortical Thickness Estimation Algorithm Gang Wang1,2 , Xiaofeng Zhang1.R.China Abstract. Cortical thickness estimation in magnetic resonance imag- ing (MRI) is an important technique

  17. Global Sediment Thickness Dataset updated for the Australian-Antarctic

    E-Print Network [OSTI]

    Müller, Dietmar

    Global Sediment Thickness Dataset updated for the Australian-Antarctic Southern Ocean Joanne author: jo.whittaker@utas.edu.au Key Points - Global minimum sediment thickness compilation updated for Australia Antarctica - Sediment thicknesses computed from seismic reflection and refraction data - Sediment

  18. Lyapunov instability of rough hard-disk fluids

    E-Print Network [OSTI]

    Jacobus A. van Meel; Harald A. Posch

    2009-04-02

    The dynamical instability of rough hard-disk fluids in two dimensions is characterized through the Lyapunov spectrum and the Kolmogorov-Sinai entropy, $h_{KS}$, for a wide range of densities and moments of inertia $I$. For small $I$ the spectrum separates into translation-dominated and rotation-dominated parts. With increasing $I$ the rotation-dominated part is gradually filled in at the expense of translation, until such a separation becomes meaningless. At any density, the rate of phase-space mixing, given by $h_{KS}$, becomes less and less effective the more the rotation affects the dynamics. However, the degree of dynamical chaos, measured by the maximum Lyapunov exponent, is only enhanced by the rotational degrees of freedom for high-density gases, but is diminished for lower densities. Surprisingly, no traces of Lyapunov modes were found in the spectrum for larger moments of inertia. The spatial localization of the perturbation vector associated with the maximum exponent however persists for any $I$.

  19. Ultrasonic thickness measuring and imaging system and method

    DOE Patents [OSTI]

    Bylenok, Paul J. (Clifton Park, NY); Patmos, William M. (Schenectady, NY); Wagner, Thomas A. (Bronswick, NY); Martin, Francis H. (Melrose, NY)

    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.

  20. Surface roughness and geological mapping at sub-hectometer scale from the High

    E-Print Network [OSTI]

    Cord, Aurélien

    and characterized in terms of roughness. Key words: Geological Processes, Impact Processes, Image Processing, Mars valuable insights into the characterization of and discrimination between these geological processesSurface roughness and geological mapping at sub-hectometer scale from the High Resolution Stereo

  1. Evolution of swelling pressure of cohesive-frictional, rough and elasto-plastic granulates

    E-Print Network [OSTI]

    Luding, Stefan

    with cohesive-frictional, rough and elasto-plastic "mi- croscopic" contact properties. The spherical particlesEvolution of swelling pressure of cohesive- frictional, rough and elasto-plastic granulates Stefan as function of pressure for different micro- scopic contact properties. Keywords: granular materials, discrete

  2. Computation of the drag force on a rough sphere close to a wall

    E-Print Network [OSTI]

    Gérard-Varet, David

    2011-01-01

    We consider the effect of surface roughness on solid-solid contact in a Stokes flow. Various models for the roughness are considered, and a unified methodology is given to derive the corresponding asymptotics of the drag force. In this way, we recover and clarify the various expressions that can be found in the litterature.

  3. American Institute of Aeronautics and Astronautics Effects of Surface Roughness on Laminar Separation Bubble over a

    E-Print Network [OSTI]

    Wang, Zhi Jian "ZJ"

    1 American Institute of Aeronautics and Astronautics Effects of Surface Roughness on Laminar Engineering and CFD Center, Iowa State University, Ames, IA 50011 Laminar separation bubbles (LSBs) are often of surface roughness on laminar separation and turbulent transition can provide insights into the design

  4. A FETCH DEPENDENT MODEL OF SEA SURFACE ROUGHNESS FOR OFFSHORE WIND POWER UTILISATION

    E-Print Network [OSTI]

    Heinemann, Detlev

    A FETCH DEPENDENT MODEL OF SEA SURFACE ROUGHNESS FOR OFFSHORE WIND POWER UTILISATION Bernhard Lange, Resources, Roughness, Coastal Sea Areas, Waves, Rødsand 1 INTRODUCTION Large offshore wind farms are being wind conditions of offshore sites, since the higher energy yield has to compensate the additional

  5. Roughness Tolerance Studies for the Undulator Beam Pipe Chamber of LCLS-II

    E-Print Network [OSTI]

    Bane, K

    2014-01-01

    We investigate the effect of wall roughness on the wakefield-induced energy variation in the undulator beam pipe of LCLS-II. We find that a wall roughness equivalent to an rms surface slope of 30 mr increases the total induced energy variation within the bunch (due to the resistive wall wake) by a modest 20%.

  6. Internal wave generation from rough topography D. A. Aguilar and B. R. Sutherlanda

    E-Print Network [OSTI]

    Sutherland, Bruce

    Internal wave generation from rough topography D. A. Aguilar and B. R. Sutherlanda Department examine internal wave generation above and in the lee of finite-amplitude periodic topography having various degrees of roughness. We show that internal waves are generated not only by flow over the hills

  7. High-order solutions of three-dimensional rough-surface scattering problems at high frequencies.

    E-Print Network [OSTI]

    Turc, Catalin

    High-order solutions of three-dimensional rough-surface scattering problems at high frequencies. I-order numerical method for the solution of high- frequency scattering problems from rough surfaces in three dimensions. The method is based on the asymptotic solution of appropriate integral equations in the high-frequency

  8. Lyapunov instability of rough hard-disk fluids Jacobus A. van Meel*

    E-Print Network [OSTI]

    Posch, Harald A.

    Lyapunov instability of rough hard-disk fluids Jacobus A. van Meel* FOM Institute for Atomic The dynamical instability of rough hard-disk fluids in two dimensions is characterized through the Lyapunov, measured by the maximum Lyapunov exponent, is only enhanced by the rotational degrees of freedom for high

  9. Rough Algebras and Automated Deduction Anita Wasilewska 1 and Laurent Vigneron 2

    E-Print Network [OSTI]

    Rusinowitch, Michaël

    of Boole himself led to the notion which we now call Boolean algebra, but one of the turning pointsRough Algebras and Automated Deduction Anita Wasilewska 1 and Laurent Vigneron 2 1 Department algebras investigated here are particular cases of topological rough algebras introduced in [26]. We

  10. Engineering Gaussian disorder at rough interfaces for light trapping in thin-film solar cells

    E-Print Network [OSTI]

    Engineering Gaussian disorder at rough interfaces for light trapping in thin-film solar cells Piotr A theoretical study of randomly rough interfaces to obtain light trapping in thin-film silicon solar cells of thin-film solar cells. © 2012 Optical Society of America OCIS codes: 040.5350, 050.1950. Reducing

  11. An approximate model for the adhesive contact of rough viscoelastic surfaces

    E-Print Network [OSTI]

    Guillaume Haiat; Etienne Barthel

    2007-09-05

    Surface roughness is known to easily suppress the adhesion of elastic surfaces. Here a simple model for the contact of \\emph{viscoelastic} rough surfaces with significant levels of adhesion is presented. This approach is derived from our previous model [E. Barthel and G. Haiat {\\em Langmuir}, 18 9362 2002] for the adhesive contact of viscoelastic spheres. For simplicity a simple loading/unloading history (infinitely fast loading and constant pull-out velocity) is assumed. The model provides approximate analytical expressions for the asperity response and exhibits the full viscoelastic adhesive contact phenomenology such as stress relaxation inside the contact zone and creep at the contact edges. Combining this model with a Greenwood-Williamson statistical modeling of rough surfaces, we propose a quantitative assessment of the adhesion to rough viscoelastic surfaces. We show that moderate viscoelasticity efficiently restores adhesion on rough surfaces over a wide dynamic range.

  12. Near-field heat transfer between a nanoparticle and a rough surface

    E-Print Network [OSTI]

    Svend-Age Biehs; Jean-Jacques Greffet

    2011-03-11

    In this work we focus on the surface roughness correction to the near-field radiative heat transfer between a nanoparticle and a material with a rough surface utilizing a direct perturbation theory up to second order in the surface profile. We discuss the different distance regimes for the local density of states above the rough material and the heat flux analytically and numerically. We show that the heat transfer rate is larger than that corresponding to a flat surface at short distances. At larger distances it can become smaller due to surface polariton scattering by the rough surface. For distances much smaller than the correlation length of the surface profile, we show that the results converge to a proximity approximation, whereas in the opposite limit the rough surface can be replaced by an equivalent surface layer.

  13. 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?

  14. 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?

  15. The Galactic thick and thin disks: differences in evolution

    E-Print Network [OSTI]

    T. V. Nykytyuk; T. V. Mishenina

    2006-05-26

    Recent observations demonstrate that the thin and thick disks of the Galaxy have different chemical abundance trends and evolution timescales. The relative abundances of $\\alpha$-elements in the thick Galactic disk are increased relative to the thin disk. Our goal is to investigate the cause of such differences in thick and thin disk abundances. We investigate the chemical evolution of the Galactic disk in the framework of the open two-zone model with gas inflow. The Galactic abundance trends for $\\alpha$-elements (Mg, Si, O) and Fe are predicted for the thin and thick Galactic disks. The star formation histories of the thin and thick disks must have been different and the gas infall must have been more intense during the thick disk evolution that the thin disk evolution.

  16. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica

    E-Print Network [OSTI]

    2013-01-01

    Surface configuration, ice thick- ness, volume and bedrockconstruction of the ice thick- ness grids. between flightof the physical ice thick- ness, rather than an “ice-

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

    Open Energy Info (EERE)

    php?titleVariableCrustalThicknessInTheWesternGreatBasin-ACompilationOfOldAndNewRefractionData&oldid793047" Categories: Missing Required Information Reference...

  18. 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,...

  19. Dictyostelium Myosin Bipolar Thick Filament Formation: Importance of Charge

    E-Print Network [OSTI]

    Spudich, James A.

    Dictyostelium Myosin Bipolar Thick Filament Formation: Importance of Charge and Specific Domains and Molecular Biology, Northwestern University, Chicago, Illinois, United States of America, 3 UNC of America Myosin-II thick filament formation in Dictyostelium is an excellent system for investigating

  20. Measurement of Paint Layer Thickness with Photothermal Infrared Radiometry

    E-Print Network [OSTI]

    Louis, Alfred K.

    Measurement of Paint Layer Thickness with Photothermal Infrared Radiometry P. Dorr, A. K. Louis-physical, optical and geometrical properties of multi-layered samples of paint on a metalic substrate. A special infrared radiometry, paint-#12;lm-thickness is measured using lock-in ampli#12;ers. The phase-di#11;erence

  1. Hazard avoidance for high-speed rough-terrain unmanned ground vehicles

    E-Print Network [OSTI]

    Spenko, Matthew J. (Matthew Julius), 1976-

    2005-01-01

    High-speed unmanned ground vehicles have important applications in rough-terrain. In these applications unexpected and dangerous situations can occur that require rapid hazard avoidance maneuvers. At high speeds, there is ...

  2. Very high efficiency phosphorescent organic light-emitting devices by using rough indium tin oxide

    SciTech Connect (OSTI)

    Zhang, Yingjie; Aziz, Hany, E-mail: h2aziz@uwaterloo.ca [Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada)

    2014-07-07

    The efficiency of organic light-emitting devices (OLEDs) is shown to significantly depend on the roughness of the indium tin oxide (ITO) anode. By using rougher ITO, light trapped in the ITO/organic wave-guided mode can be efficiently extracted, and a light outcoupling enhancement as high as 40% is achieved. Moreover, contrary to expectations, the lifetime of OLEDs is not affected by ITO roughness. Finally, an OLED employing rough ITO anode that exhibits a current efficiency of 56?cd/A at the remarkably high brightness of 10{sup 5}?cd/m{sup 2} is obtained. This represents the highest current efficiency at such high brightness to date for an OLED utilizing an ITO anode, without any external light outcoupling techniques. The results demonstrate the significant efficiency benefits of using ITO with higher roughness in OLEDs.

  3. Comprehensive Evaluation Model of Building Energy Efficiency Based on Rough Sets Theory 

    E-Print Network [OSTI]

    Ding, L.; Ruan, X.; Huang, J.; Li, Y.

    2006-01-01

    In order to improve the objectivity of building energy efficiency evaluation, this paper uses a new method to evaluate building energy efficiency on the basis of rough sets theory. The contribution of different subentry evaluation indicators...

  4. Significance of the Casimir force and surface roughness for actuation dynamics of MEMS

    E-Print Network [OSTI]

    Wijnand Broer; George Palasantzas; Jasper Knoester; Vitaly B. Svetovoy

    2013-03-14

    Using the measured optical response and surface roughness topography as inputs, we perform realistic calculations of the combined effect of Casimir and electrostatic forces on the actuation dynamics of micro-electromechanical systems (MEMS). In contrast with the expectations, roughness can influence MEMS dynamics even at distances between bodies significantly larger than the root-mean-square roughness. This effect is associated with statistically rare high asperities that can be locally close to the point of contact. It is found that, even though surface roughness appears to have a detrimental effect on the availability of stable equilibria, it ensures that those equilibria can be reached more easily than in the case of flat surfaces. Hence our findings play a principal role for the stability of microdevices such as vibration sensors, switches, and other related MEM architectures operating at distances below 100 nm.

  5. 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.

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

    DOE Patents [OSTI]

    Bernitsas, Michael M. (Saline, MI); Raghavan, Kamaldev (Houston, TX)

    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).

  7. 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.

  8. hp-finite-elements for simulating electromagnetic fields in optical devices with rough textures

    E-Print Network [OSTI]

    Burger, S; Hammerschmidt, M; Herrmann, S; Pomplun, J; Schmidt, F; Wohlfeil, B; Zschiedrich, L

    2015-01-01

    The finite-element method is a preferred numerical method when electromagnetic fields at high accuracy are to be computed in nano-optics design. Here, we demonstrate a finite-element method using hp-adaptivity on tetrahedral meshes for computation of electromagnetic fields in a device with rough textures. The method allows for efficient computations on meshes with strong variations in element sizes. This enables to use precise geometry resolution of the rough textures. Convergence to highly accurate results is observed.

  9. Optorheological Studies of Sheared Confined Fluids with Mesoscopic Thickness

    E-Print Network [OSTI]

    Granick, Steve

    limit apart from surface roughness. Capacitance sensors or optical interferometry is used to monitor-resolved infrared spectroscopy. To demonstrate capabilities of this new instrument, we describe an experiment methods to study molecular orientation. For example, the evaluation of dichroism is often used

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

    DOE Patents [OSTI]

    Carlson, Nancy M. (Idaho Falls, ID); Johnson, John A. (Idaho Falls, ID); Tow, David M. (Idaho Falls, ID); Walter, John B (Idaho Falls, ID)

    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.

  11. 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.

  12. 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.

  13. 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

  14. Crustal thickness and support of topography on Venus

    E-Print Network [OSTI]

    James, Peter Benjamin

    The topography of a terrestrial planet can be supported by several mechanisms: (1) crustal thickness variations, (2) density variations in the crust and mantle, (3) dynamic support, and (4) lithospheric stresses. Each of ...

  15. Reactor physics assessment of thick silicon carbide clad PWR fuels

    E-Print Network [OSTI]

    Bloore, David A. (David Allan)

    2013-01-01

    High temperature tolerance, chemical stability and low neutron affinity make silicon carbide (SiC) a potential fuel cladding material that may improve the economics and safety of light water reactors (LWRs). "Thick" SiC ...

  16. Gender Effects on Cortical Thickness , Thompson PM1

    E-Print Network [OSTI]

    Thompson, Paul

    thickness was estimated voxel by voxel and projected as a local value (mm) onto the cortical surface, where brains that appears to involve the architecture of the cortical mantle. We detected significantly greater

  17. Thickness trends and sequence stratigraphy of the Middle

    E-Print Network [OSTI]

    Engelder, Terry

    Thickness trends and sequence stratigraphy of the Middle Devonian Marcellus Formation, Appalachian to the lithostratigraphy and sequence stratigraphy of the Middle and Upper Devonian shale succession of the Appalachian

  18. 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

  19. A comparison of thick film and thin film traffic stripes 

    E-Print Network [OSTI]

    Keese, Charles J

    1952-01-01

    of this thesis. CONTESTS Introduction ~ ~ ~ ~ ~ 1 Scope and Obfectives Method of Conducting Road Service Tests ~ ~ ~ ~ ~ ~ ~ ~ 7 ~ ~ ~ ~ ~ ~ ~ ~ ~ 8 PART I A Comparison of Paint Films of Various Thicknesses . . . . . . . . ~ ~, ~, ~ 72 App1ioation... of Test Stripes . Results of Thiokness Tests . 13 19 Conclusions 2$ PART II A Comparison of Various Thick Film and Thin Film Traffic Stripes. 26 Paint Stripes Over Adhesive Films Rosin Striping Compounds. . . + ~ . , ~ 29 ~ ~ ~ Preforsmd Plastic...

  20. 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.

  1. Ionospheric slab thickness in middle and low latitudes

    SciTech Connect (OSTI)

    Davies, K.; Liu, X.M. (NOAA, Space Environment Laboratory, Boulder, CO (United States))

    1991-08-01

    The equivalent slab thickness of the ionosphere at 15 stations in middle and low latitudes was studied to determine its dependence on solar cycle and location. The data were grouped by season. The following are the major conclusions. There appears to be little or no geographical, or geomagnetic, dependence. The slab thickness varies approximately linearly with the 12-month smoothed values of the 10.7-cm solar radio flux. In middle latitudes the winter midnight thickness is essentially independent of the flux, whereas in summer and equinox the midnight thickness increases with increase of solar flux. The noon thickness increases with increase of solar flux in all seasons. The zero-order Fourier coeffficients for the diurnal curves at all 15 stations were expressed as linear functions of the 10.7-cm flux. The higher harmonic coefficients showed no appreciable dependence on solar flux. The pronounced predawn increase in slab thickness is caused by low values of the maximum electron density, not by increase of total electron content. 10 refs.

  2. A Unifying Framework to Quantify the Effects of Substrate Interactions, Stiffness, and Roughness on the Dynamics of Thin Supported Polymer Films

    E-Print Network [OSTI]

    Paul Z. Hanakata; Beatriz A. Pazmiño Betancourt; Jack F. Douglas; Francis W. Starr

    2015-02-10

    Changes in the dynamics of supported polymer films in comparison to bulk materials involve a complex convolution of effects, such as substrate interactions, roughness and compliance, in addition to film thickness. We consider molecular dynamics simulations of substrate-supported, coarse-grained polymer films where these parameters are tuned separately to determine how each of these variables influence the molecular dynamics of thin polymer films. We find that all these variables significantly influence the film dynamics, leading to a seemingly intractable degree of complexity in describing these changes. However, by considering how these constraining variables influence string-like collective motion within the film, we show that all our observations can be understood in a unified and quantitative way. More specifically, the string model for glass-forming liquids implies that the changes in the structural relaxation of these films are governed by the changes in the average length of string-like cooperative motions and this model is confirmed under all conditions considered in our simulations. Ultimately, these changes are parameterized in terms of just the activation enthalpy and entropy for molecular organization, which have predictable dependences on substrate properties and film thickness, offering a promising approach for the rational design of film properties.

  3. The friction factor of two-dimensional rough-boundary turbulent soap film flows

    E-Print Network [OSTI]

    Nicholas Guttenberg; Nigel Goldenfeld

    2009-03-25

    We use momentum transfer arguments to predict the friction factor $f$ in two-dimensional turbulent soap-film flows with rough boundaries (an analogue of three-dimensional pipe flow) as a function of Reynolds number Re and roughness $r$, considering separately the inverse energy cascade and the forward enstrophy cascade. At intermediate Re, we predict a Blasius-like friction factor scaling of $f\\propto\\textrm{Re}^{-1/2}$ in flows dominated by the enstrophy cascade, distinct from the energy cascade scaling of $\\textrm{Re}^{-1/4}$. For large Re, $f \\sim r$ in the enstrophy-dominated case. We use conformal map techniques to perform direct numerical simulations that are in satisfactory agreement with theory, and exhibit data collapse scaling of roughness-induced criticality, previously shown to arise in the 3D pipe data of Nikuradse.

  4. 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.

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

    DOE Patents [OSTI]

    Folta, James A. (2262 Hampton Rd., Livermore, CA 94550); Montcalm, Claude (14 Jami St., Livermore, CA 94550); Walton, Christopher (2927 Lorina St., #2, Berkeley, CA 94705-1852)

    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.

  6. General contact mechanics theory for randomly rough surfaces with application to rubber friction

    E-Print Network [OSTI]

    Michele Scaraggi; Bo N. J. Persson

    2015-06-23

    We generalize the Persson contact mechanics and rubber friction theory to the case where both surfaces have surface roughness. The solids can be rigid, elastic or viscoelastic, and can be homogeneous or layered. We calculate the contact area, the viscoelastic contribution to the friction force, and the average interfacial separation as a function of the sliding speed and the nominal contact pressure. We illustrate the theory with numerical results for a rubber block sliding on a road surface. We find that with increasing sliding speed, the influence of the roughness on the rubber block decreases, and for typical sliding speeds involved in tire dynamics it can be neglected.

  7. 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.

  8. Atmospheric Momentum Roughness Applied to Stage-Discharge Relationships in Flood Plains

    E-Print Network [OSTI]

    Atmospheric Momentum Roughness Applied to Stage-Discharge Relationships in Flood Plains Jennifer M and discharge relationship for turbulent flows over vegetated flood plains. The model is based on the turbulent sites. The model estimates of the flood flow discharges from a natural site are compared to observed

  9. Numerical method for calculating the apparent eddy current conductivity loss on randomly rough surfaces

    E-Print Network [OSTI]

    Nagy, Peter B.

    Numerical method for calculating the apparent eddy current conductivity loss on randomly rough Because of their frequency-dependent penetration depth, eddy current measurements are capable of mapping of eddy current conductivity, thereby decreasing the accuracy of the measurements, especially in thermally

  10. A simple numerical model of the apparent loss of eddy current conductivity due to surface roughness

    E-Print Network [OSTI]

    Nagy, Peter B.

    A simple numerical model of the apparent loss of eddy current conductivity due to surface roughness of eddy current conductivity has been suggested as a possible means to allow the nondestructive evaluation, the path of the eddy current must follow a more tortuous route in the material, which produces a reduction

  11. Importance of thermal effects and sea surface roughness for offshore wind resource assessment

    E-Print Network [OSTI]

    Heinemann, Detlev

    Importance of thermal effects and sea surface roughness for offshore wind resource assessment National Laboratory, Roskilde, Denmark Abstract The economic feasibility of offshore wind power utilisation depends on the favourable wind conditions offshore compared to sites on land, which have to compensate

  12. FRICTION FACTOR IN HIGH PRESSURE NATURAL GAS PIPELINES FROM ROUGHNESS MEASUREMENTS

    E-Print Network [OSTI]

    Gudmundsson, Jon Steinar

    FRICTION FACTOR IN HIGH PRESSURE NATURAL GAS PIPELINES FROM ROUGHNESS MEASUREMENTS DETERMINATION DU and Technology, Norway ABSTRACT Pressure drop experiments on natural gas flow at 80 to 120 bar pressure and high of natural gas at typical operating pressures (100-180 bar). At such Reynolds numbers the classical Colebrook

  13. Flow over rough topography. A preliminary study with high resolution topography at Ormen Lange

    E-Print Network [OSTI]

    Avlesen, Helge

    Flow over rough topography. A preliminary study with high resolution topography at Ormen Lange not able to march as long in time as desired, due to stability issues. On the given topography for selected horizontal sections, after im- posing a constant velocity flow over the given topography

  14. Under consideration for publication in J. Fluid Mech. 1 Nonlinear dynamics over rough topography

    E-Print Network [OSTI]

    Vanneste, Jacques

    Under consideration for publication in J. Fluid Mech. 1 Nonlinear dynamics over rough topography-dimensional, pe- riodic or random, small-scale topography is investigated using an asymptotic approach. Averaged (or homogenised) evolution equations which account for the flow-topography in- teraction are derived

  15. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 1 A Simplified Formulation for Rough Surface

    E-Print Network [OSTI]

    IEEEProof IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 1 A Simplified Formulation for Rough paper. To download the IEEE Taxonomy, go to http://www.30 ieee.org/documents/taxonomy_v101.pdf.31 I, OH 43210 USA. Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee

  16. Effect of Substrate Roughness on D Spacing Supports Theoretical Resolution of Vapor Pressure Paradox

    E-Print Network [OSTI]

    Nagle, John F.

    Effect of Substrate Roughness on D Spacing Supports Theoretical Resolution of Vapor Pressure with and provides experimental support for a recently proposed theoretical resolution of the vapor pressure paradox has been called the vapor pressure paradox (Rand and Parsegian, 1989). Resolving this paradox

  17. Stress Drop during Earthquakes: Effect of Fault Roughness Scaling by Thibault Candela, Franois Renard,*

    E-Print Network [OSTI]

    Schmittbuhl, Jean

    Stress Drop during Earthquakes: Effect of Fault Roughness Scaling by Thibault Candela, François parameter of static stress drop during an earthquake is related to the scaling properties of the fault and focusing on elastic deformation of the topography, which is the dominant mode at large scales, the stress

  18. Hydrothermal coupling in a self-affine rough fracture A. Neuville,* R. Toussaint, and J. Schmittbuhl

    E-Print Network [OSTI]

    Schmittbuhl, Jean

    - thermics is an intensively developing field. Deep enhanced geothermal systems EGSs are based on the energy the hydraulic flow and subse- quently to enhance the thermal exchange. Fracture roughness might, in the opposite as an ellipse or a poly- hedron. This is the case in most fracture network models used for geothermal 10

  19. Roughly 120 years ago, an incon-spicuous pest took a ride on a

    E-Print Network [OSTI]

    Latchininsky, Alexandre

    Roughly 120 years ago, an incon- spicuous pest took a ride on a ship from Europe bound discussed the projects he had avail- able, the horn fly project fit best with my background. Horn Fly First, the cattle use costly energy meant for growth to rid themselves of the flies. Some of the behavioral changes

  20. Hydro-thermal flow in a rough fracture EC Contract SES6-CT-2003-502706

    E-Print Network [OSTI]

    Toussaint, Renaud

    Hydro-thermal flow in a rough fracture EC Contract SES6-CT-2003-502706 PARTICIPANT ORGANIZATION NAME: CNRS Synthetic 2nd year report Related with Work Package............ HYDRO-THERMAL FLOW in the influence of a realistic geometry of the fracture on its hydro-thermal response. Several studies have

  1. Relations in Mathematical Morphology with applications to Graphs and Rough Sets

    E-Print Network [OSTI]

    Stell, John

    School of Computing, University of Leeds Leeds, LS2 9JT, U.K. jgs@comp.leeds.ac.uk Abstract. Rough sets of morphology for graphs. The structure of the paper is as follows. I begin in Section 2 with a brief review

  2. Light trapping in thin-film solar cells with randomly rough and hybrid

    E-Print Network [OSTI]

    Light trapping in thin-film solar cells with randomly rough and hybrid textures Piotr Kowalczewski. M. Smets, and M. Zeman, "Plasmonic light trapping in thin-film silicon solar cells with improved Lambertian limits in thin film silicon solar cells with 1D and 2D periodic patterns," Opt. Express 20, A224­A

  3. ENGINEERED SUBSTRATES FOR THIN-FILM SOLAR CELLS: SCATTERING PROPERTIES OF 1D ROUGHNESS

    E-Print Network [OSTI]

    ENGINEERED SUBSTRATES FOR THIN-FILM SOLAR CELLS: SCATTERING PROPERTIES OF 1D ROUGHNESS S. Del Sorbo, Optical Properties, Substrates, Texturisation, Thin Film Solar Cells 1 MOTIVATION OF THIS WORK The aim of thin film technology is to reduce both the electrical transport losses in the bulk region of a solar

  4. Molecular Dynamics Simulation of Thin Films with Rough and Asymmetric Interfaces

    E-Print Network [OSTI]

    Walker, D. Greg

    Molecular Dynamics Simulation of Thin Films with Rough and Asymmetric Interfaces N.A. Roberts with the use of interfaces and shows that pristine, imperfect and asymmetric interfaces in thin films can interface whose features are of the order of the phonon wavelength. At a constant temperature difference

  5. Gravitational quantum states of neutrons in a rough waveguide A. E. Meyerovich

    E-Print Network [OSTI]

    Meyerovich, Alex

    of such states is indeed a major experimental challenge. What is more, the measure- ments in this energy range/absorber. The analysis is based on a recently developed theory of quantum transport along random rough walls which and are more efficient than the processes involving the intermediate states. The theoretical results

  6. Measurement of sheath thickness at a floating potential

    SciTech Connect (OSTI)

    Han, Hyung-Sik; Lee, Hyo-Chang; Oh, Se-Jin; Chung, Chin-Wook, E-mail: joykang@hanyang.ac.kr [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)] [Department of Electrical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of)

    2014-02-15

    In a cylindrical Langmuir probe measurement, ion current is collected from the surface of the sheath surrounded at probe tip, not at the surface of the probe tip. By using this, the sheath thickness can be obtained, if we know some unknown parameters, such as ion current, plasma density, and electron temperature. In this paper, we present a method to measure sheath thickness by using a wave cutoff method and a floating harmonic method. The measured result is in a good agreement with Allen-Boyd-Reynolds theory.

  7. Method and apparatus for thickness measurement using microwaves

    DOE Patents [OSTI]

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

  8. Process for manufacture of thick film hydrogen sensors

    DOE Patents [OSTI]

    Perdieu, Louisa H. (Overland Park, KS)

    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.

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

    SciTech Connect (OSTI)

    Rodríguez-Prada, F. A.; García, 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.

  10. 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

  11. 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.

  12. Very thick holographic nonspatial filtering of laser beams

    E-Print Network [OSTI]

    Shahriar, Selim

    of a thick photo- polymer with diffusion amplification (PDA). We report results of holo- graphic nonspatial Society of Photo-Optical In- strumentation Engineers. [S0091-3286(97)01606-1] Subject terms: holography information if the input laser beam has an intensity minimum at a critical feature location. It is also

  13. Wind assessment in complex terrain with the numeric model Aiolos implementation of the influence of roughness changes and stability

    E-Print Network [OSTI]

    Heinemann, Detlev

    to the influence of roughness changes and the thermal stratification. Wind potential assessments of two sites of roughness changes on the terrain surface and thermal stratification of the at- mosphere are taken a neutral thermal stratification situation is assumed. But for a north eu- ropean situation a light stable

  14. Wetting Transitions of Condensed Droplets on Superhydrophobic Surfaces with Two-Tier Roughness

    E-Print Network [OSTI]

    Lv, Cunjing; Zhang, Xiwen; He, Feng

    2015-01-01

    Although realizing wetting transitions of droplets spontaneously on solid rough surfaces is quite challenging, it is becoming a key research topic in many practical applications which require highly efficient removal of liquid. We report wetting transitions of condensed droplets occurring spontaneously on pillared surfaces with two-tier roughness owing to excellent superhydrophobicity. The phenomenon results from further decreased Laplace pressure on the top side of the individual droplet when its size becomes comparable to the scale of the micropillars, which leads to a surprising robust spontaneous wetting transition, from valleys to tops of the pillars. A simple scaling law is derived theoretically, which demonstrates that the critical size of the droplet is determined by the space of the micropillars. For this reason, highly efficient removal of water benefits greatly from smaller micropillar space. Furthermore, three wetting transition modes exist, in which the in situ wetting behaviors are in good agree...

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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

  20. Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

    E-Print Network [OSTI]

    Carmignani, B

    2005-01-01

    Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

  1. Energy production rates in fluid mixtures of inelastic rough hard spheres

    E-Print Network [OSTI]

    Andrés Santos; Gilberto M. Kremer; Vicente Garzó

    2010-07-16

    The aim of this work is to explore the combined effect of polydispersity and roughness on the partial energy production rates and on the total cooling rate of a granular fluid mixture. We consider a mixture of inelastic rough hard spheres of different number densities, masses, diameters, moments of inertia, and mutual coefficients of normal and tangential restitution. Starting from the first equation of the BBGKY hierarchy, the collisional energy production rates associated with the translational and rotational temperatures ($T_i^\\text{tr}$ and $T_i^\\text{rot}$) are expressed in terms of two-body average values. Next, those average values are estimated by assuming a velocity distribution function based on maximum-entropy arguments, allowing us to express the energy production rates and the total cooling rate in terms of the partial temperatures and the parameters of the mixture. Finally, the results are applied to the homogeneous cooling state of a binary mixture and the influence of inelasticity and roughness on the temperature ratios $T_1^\\text{tr}/T_1^\\text{rot}$, $T_2^\\text{tr}/T_1^\\text{tr}$, and $T_2^\\text{rot}/T_1^\\text{rot}$ is analyzed.

  2. Molecular Dynamics Simulation Study of Interaction between Model Rough Hydrophobic Surfaces

    E-Print Network [OSTI]

    Changsun Eun; Max L. Berkowitz

    2011-06-01

    We study some aspects of hydrophobic interaction between molecular rough and flexible model surfaces. The model we use in this work is based on a model we used previously (Eun, C.; Berkowitz, M. L. J. Phys. Chem. B 2009, 113, 13222-13228), when we studied the interaction between model patches of lipid membranes. Our original model consisted of two graphene plates with attached polar headgroups; the plates were immersed in a water bath. The interaction between such plates can be considered as an example of a hydrophilic interaction. In the present work we modify our previous model by removing the charge from the zwitterionic headgroups. As a result of this procedure, the plate character changes; it becomes hydrophobic. By separating the total interaction (or potential of mean force, PMF) between plates into the direct and the water-mediated interactions we observe that the latter changes from repulsive to attractive, clearly emphasizing the important role of water as a medium. We also investigate the effect of roughness and flexibility of the headgroups on the interaction between plates and observe that roughness enhances the character of the hydrophobic interaction. The presence of a dewetting transition in a confined space between charge-removed plates confirms that the interaction between plates is strongly hydrophobic. In addition, we notice that there is a shallow local minimum in the PMF in case of charge-removed plates. We find that this minimum is associated with the configurational changes that flexible headgroups undergo, as the two plates are brought together.

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

    DOE Patents [OSTI]

    Henager, Jr., Charles H. (Kennewick, WA); Knoll, Robert W. (Menomonee Falls, WI)

    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.

  5. Probing the neutron skin thickness in collective modes of excitation

    E-Print Network [OSTI]

    Nils Paar; Andrea Horvat

    2014-01-13

    Nuclear collective motion provides valuable constraint on the size of neutron-skin thickness and the properties of nuclear matter symmetry energy. By employing relativistic nuclear energy density functional (RNEDF) and covariance analysis related to $\\chi^2$ fitting of the model parameters, relevant observables are identified for dipole excitations, which strongly correlate with the neutron-skin thickness $(r_{np})$, symmetry energy at saturation density $(J)$ and slope of the symmetry energy $(L)$. Using the RNEDF framework and experimental data on pygmy dipole strength ($^{68}$Ni, $^{132}$Sn, $^{208}$Pb) and dipole polarizability ($^{208}$Pb), it is shown how the values of $J$, and $L$, and $r_{np}$ are constrained. The isotopic dependence of moments associated to dipole excitations in $^{116-136}$Sn shows that the low-energy dipole strength and polarizability in neutron-rich nuclei display strong sensitivity to the symmetry energy parameter $J$, more pronounced than in isotopes with moderate neutron-to-proton number ratios.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Structural connections in plywood friction-fit construction

    E-Print Network [OSTI]

    Wagner, Mali E. (Mali Esther)

    2014-01-01

    CNC mills allow precise fabrication of planar parts with embedded joinery which can be assembled into complex 3D geometries without the use of foreign mechanical fasteners. This thesis studies the behavior of the friction-fit ...

  12. Effect of the porosity on the fracture surface roughness of sintered materials: From anisotropic to isotropic self-affine scaling

    E-Print Network [OSTI]

    Tristan Cambonie; Jonathan Bares; Lamine Hattali; Daniel Bonamy; Véronique Lazarus; Harold Auradou

    2015-01-16

    To unravel how the microstructure affects the fracture surface roughness in heterogeneous brittle solids like rocks or ceramics, we characterized the roughness statistics of post-mortem fracture surfaces in home-made materials of adjustable microstructure length-scale and porosity, obtained by sintering monodisperse polystyrene beads. Beyond the characteristic size of disorder, the roughness profiles are found to exhibit self-affine scaling features evolving with porosity. Starting from a null value and increasing the porosity, we quantitatively modify the self-affine scaling properties from anisotropic (at low porosity) to isotropic (for porosity larger than 10 %).

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

    SciTech Connect (OSTI)

    Quereda, J.; Castellanos-Gomez, A.; Agraït, 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.

  14. Rough contact mechanics for graded bulk rheology: The role of small-scale wavelengths on rubber friction

    E-Print Network [OSTI]

    Michele Scaraggi; Davide Comingio

    2015-10-13

    We present a numerical model for the prediction of the rough contact mechanics of a viscoelastic block, with graded rheology, in steady sliding contact with a randomly rough rigid surface. In particular, we derive the effective surface response of a stepwise or continuously-graded block in the Fourier domain, which is then embedded in a Fourier-based residuals molecular dynamic formulation of the contact mechanics. Finally we discuss on the role of small-scale wavelengths on rubber friction and contact area, and we demonstrate that the rough contact mechanics exhibits effective interface properties which converge to asymptotes upon increase of the small-scale roughness content, when a realistic rheology of the confinement is taken into account.

  15. MEMS-based contact stress field measurements at a rough elastomeric layer: local test of Amontons' friction law in static

    E-Print Network [OSTI]

    Adda-Bedia, Mokhtar

    MEMS-based contact stress field measurements at a rough elastomeric layer: local test of Amontons/Universit´e Paris 6, Paris, France Abstract. We present the results of recent friction experiments in which a MEMS

  16. Lyman alpha Transfer in a thick, dusty, and static medium

    E-Print Network [OSTI]

    Sang-Hyeon Ahn; Hee-Won Lee; Hyung-Mok Lee

    2000-06-13

    We developed a Monte Carlo code that describes the resonant Lyman alpha line transfer in an optically thick, dusty, and static medium. The code was tested against the analytic formula derived by Neufeld (1990). We explain the line transfer mechanism for a wide range of line center optical depths by tracing histories of photons in the medium. We find that photons escape from the medium by a series of wing scatterings, during which polarization may develop. We applied our code to examine the amount of dust extinction around the Lyman alpha in primeval galaxies. Brief discussions on the astrophysical application of our work are presented.

  17. 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.

  18. 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.

  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. 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.

  1. 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.

  2. 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.

  3. Force and torque acting on particles in a transitionally rough open channel flow

    E-Print Network [OSTI]

    Chan-Braun, Clemens; Uhlmann, Markus

    2011-01-01

    Direct numerical simulation of open channel flow over a geometrically rough wall has been performed at a bulk Reynolds number of approximately 2900. The wall consisted of a layer of spheres in a square arrangement. Two cases have been considered. In the first case the spheres are small (with diameter equivalent to 10.7 wall units) and the limit of the hydraulically smooth flow regime is approached. In the second case the spheres are more than three times larger (49.3 wall units) and the flow is in the transitionally rough flow regime. Special emphasis is given on the characterisation of the force and torque acting on a particle due to the turbulent flow. It is found that in both cases the mean drag, lift and spanwise torque are to a large extent produced at the top region of the particle surface. The intensity of the particle force fluctuations is significantly larger in the large-sphere case, while the trend differs for the fluctuations of the individual components of the torque. A simplified model is used t...

  4. Steady state in a gas of inelastic rough spheres heated by a uniform stochastic force

    E-Print Network [OSTI]

    Francisco Vega Reyes; Andrés Santos

    2015-11-04

    We study here the steady state attained in a granular gas of inelastic rough spheres that is subject to a spatially uniform random volume force. The stochastic force has the form of the so-called white noise and acts by adding impulse to the particle translational velocities. We work out an analytical solution of the corresponding velocity distribution function from a Sonine polynomial expansion that displays energy non-equipartition between the translational and rotational modes, translational and rotational kurtoses, and translational-rotational velocity correlations. By comparison with a numerical solution of the Boltzmann kinetic equation (by means of the Direct Simulation Monte Carlo method) we show that our analytical solution provides a good description that is quantitatively very accurate in certain ranges of inelasticity and roughness. We also find three important features that make the forced granular gas steady state very different from the homogeneous cooling state (attained by an unforced granular gas). First, the marginal velocity distributions are always close to a Maxwellian. Second, there is a continuous transition to the purely smooth limit (where the effects of particle rotations are ignored). And third, the angular translational-rotational velocity correlations show a preference for a quasiperpendicular mutual orientation (which is called "lifted-tennis-ball" behavior).

  5. Effects of Membrane- and Catalyst-layer-thickness Nonuniformities in Polymer-electrolyte Fuel Cells

    E-Print Network [OSTI]

    Weber, Adam Z.; Newman, John

    2006-01-01

    from various parts of a PEFC, thickness distributions can beour previously developed PEFC models. 4,5 The simulations

  6. The effect of film thickness on the failure strain of polymer-supported metal films

    E-Print Network [OSTI]

    Suo, Zhigang

    The effect of film thickness on the failure strain of polymer-supported metal films Nanshu Lu-supported copper films with a strong (1 1 1) fiber texture and with thicknesses varying from 50 nm to 1 lm. Films with thicknesses below 200 nm fail by intergranular fracture at elongations of only a few percent. Thicker films

  7. Thick Filament Length and Isoform Composition Determine Self-Organized Contractile Units in Actomyosin Bundles

    E-Print Network [OSTI]

    Gardel, Margaret

    Thick Filament Length and Isoform Composition Determine Self-Organized Contractile Units motors are clustered into thick filaments. Although the role of mechanochemistry is well appreciated, the extent to which thick filament length regulates actomyosin contractility is unknown. Here, we study

  8. Bilayer thickness effects on nanoindentation behavior of Ag/Ni multilayers

    E-Print Network [OSTI]

    Hong, Soon Hyung

    by nanoindentation hardness and creep tests. The hardness increased with decreasing bilayer thickness, although of nanoindentation creep tests on Ag/Ni nanomultilayers with various bilayer thicknesses. Multilayered Ag/Ni films thickness. A nanoindentation creep test was used to study the creep behavior of nano- scale multilayers

  9. Test of CZT Detectors with Different Pixel Pitches and Thicknesses

    E-Print Network [OSTI]

    Qiang Li; Alfred III Garson; Ira Jung; Michael Groza; Paul Dowkontt; Richard Bose; Garry Simburger; Arnold Burger; Henric Krawczynski

    2007-12-08

    The Modified Horizontal Bridgman (MHB) process produces Cadmium Zinc Telluride (CZT) crystals with high yield and excellent homogeneity. Various groups,including our own, previously reported on the test of 2x2x0.5 cm3 MHB CZT detectors grown by the company Orbotech and read out with 8x8 pixels. In this contribution, we describe the optimization of the photolithographic process used for contacting the CZT detector with pixel contacts. The optimized process gives a high yield of good pixels down to pixel diameters/pitches of 50 microns. Furthermore, we discuss the performance of 0.5 cm and 0.75 cm thick detectors contacted with 64 and 225 pixel read out with the RENA-3 ASICs from the company NOVA R&D.

  10. Thickness dependent structural, optical and electrical properties of CuIn{sub 0.8}Ga{sub 0.2}Se{sub 2} thin films deposited by pulsed laser deposition

    SciTech Connect (OSTI)

    Mishra, Pradeep K.; Prasad, J. N. [University Department of Physics, Ranchi University, Ranchi-834008 (India); Gautam, Yogendra K.; Jain, Ravish K.; Choudhary, A. K.; Chandra, Ramesh [Institute Instrumentation Centre, Indian Institute of Technology, Roorkee-247667 (India); Kumar, Ashwani [Institute Instrumentation Centre, Indian Institute of Technology, Roorkee-247667, India and Centre for Nanotechnology, Indian Institute of Technology, Roorkee-247667 (India)

    2014-01-28

    CuIn{sub 0.8}Ga{sub 0.2}Se{sub 2} (CIGS) polycrystalline thin films have been deposited on soda lime glass substrate at different deposition time by pulsed laser deposition. The effect of thickness on structural, surface morphological, optical and electrical properties of thin films were investigated by X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM), atomic force microscopy (AFM), UV-Vis-NIR spectrophotometer and electrical measurement unit. XRD study reveals that all deposited films are polycrystalline in nature and have tetragonal phase of CIGS. Crystallinity of CIGS films has been found to improve with increase in thickness of CIGS films as evidenced by sharp XRD peaks for (112) orientation. Grain size and rms surface roughness of CIGS films have been found to be increased with increase in thickness. All the deposited CIGS films exhibit direct band gap semiconducting behaviour with ?10{sup 6} cm{sup ?1} absorption co-efficient. Optical band gap and resistivity of CIGS films have been found to decrease with increase in thickness.

  11. Thick Pixelated CZT Detectors With Isolated Steering Grids

    E-Print Network [OSTI]

    I. Jung; A. B. Garson; J. S. Perkins; H. Krawczynski; J. Matteson; R. T. Skelton; A. Burger; M. Groza

    2005-11-18

    We explore the possibility to improve the performance of 0.5 cm thick Cadmium Zinc Telluride (CZT) detectors with the help of steering grids on the anode side of the detectors. Steering grids can improve the energy resolution of CZT detectors by enhancing the small pixel effect; furthermore, they can increase their detection efficiency by steering electrons to the anode pixels which otherwise would drift to the area between pixels. Previously, the benefit of steering grids had been compromised by additional noise associated with currents between the steering grids and the anode pixels. We use thin film deposition techniques to isolate the steering grid from the CZT substrate by a 150 nm thick layer of the isolator Aluminiumoxide. While the thin layer does not affect the beneficial effect of the steering grid on the weighting potentials and the electric field inside the detector, it suppresses the currents between the steering grid and the anode pixels. In this contribution, we present first results from a 2 x 2 x 0.5 cm CZT detector with 8 x 8 pixels that we tested before and after deposition of an isolated steering grid. The steering grid improves the 662 keV energy resolution of the detector by a factor of 1.3 (from about 2% to about 1.5%), while not reducing the detection efficiency. To gain further insights into the detector response in the region between pixels, we measured energy spectra with a collimated Cs137 source. The collimator measurements can be used to enhance our understanding of energy spectra measured under flood illumination of the detectors.

  12. 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)

  13. Improved detection of rough defects for ultrasonic NDE inspections based on finite element modeling of elastic wave scattering

    SciTech Connect (OSTI)

    Pettit, J. R. [Rolls-Royce Nuclear, PO BOX 2000, Derby, UK, DE21 7XX and Research Centre for NDE, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Walker, A. [Rolls-Royce Nuclear, PO BOX 2000, Derby DE21 7XX (United Kingdom); Lowe, M. J. S. [Research Centre for NDE, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom)

    2014-02-18

    Defects which posses rough surfaces greatly affect ultrasonic wave scattering behaviour, often reducing the magnitude of reflected signals. Ultrasonic inspections rely upon this response for detecting and sizing flaws. For safety critical components reliable characterisation is crucial. Therefore, providing an accurate means to predict reductions in signal amplitude is essential. An extension of Kirchhoff theory has formed the basis for the UK power industry inspection justifications. However, it is widely recognised that these predictions are pessimistic owing to analytical approximations. A numerical full field modelling approach does not fall victim to such limitations. Here, a Finite Element model is used to aid in setting a non-conservative reporting threshold during the inspection of a large pressure vessel forging that might contain embedded rough defects. The ultrasonic response from multiple rough surfaces defined by the same statistical class is calculated for normal incident compression waves. The approach is validated by comparing coherent scattering with predictions made by Kirchhoff theory. At lower levels of roughness excellent agreement is observed, whilst higher values confirm the pessimism of Kirchhoff theory. Furthermore, the mean amplitude in the specular direction is calculated. This represents the information obtained during an inspection, indicating that reductions due to increasing roughness are significantly less than the coherent component currently being used.

  14. 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 (Livermore, CA); Folta, James Allen (Livermore, CA); Walton, Christopher Charles (Berkeley, CA)

    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.

  15. Water-waves modes trapped in a canal by a body with the rough surface

    E-Print Network [OSTI]

    G. Cardone; T. Durante; S. A. Nazarov

    2009-10-06

    The problem about a body in a three dimensional infinite channel is considered in the framework of the theory of linear water-waves. The body has a rough surface characterized by a small parameter $\\epsilon>0$ while the distance of the body to the water surface is also of order $\\epsilon$. Under a certain symmetry assumption, the accumulation effect for trapped mode frequencies is established, namely, it is proved that, for any given $d>0$ and integer $N>0$, there exists $\\epsilon(d,N)>0$ such that the problem has at least $N$ eigenvalues in the interval $(0,d)$ of the continuous spectrum in the case $\\epsilon\\in(0,\\epsilon(d,N)) $. The corresponding eigenfunctions decay exponentially at infinity, have finite energy, and imply trapped modes.

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

    SciTech Connect (OSTI)

    Li, Ting (Ventura, CA)

    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.

  17. 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.

  18. Adhesion between elastic solids with randomly rough surfaces: comparison of analytical theory with molecular dynamics simulations

    E-Print Network [OSTI]

    N. Mulakaluri; B. N. J. Persson

    2011-12-22

    The adhesive contact between elastic solids with randomly rough, self affine fractal surfaces is studied by molecular dynamics (MD) simulations. The interfacial binding energy obtained from the simulations of nominally flat and curved surfaces is compared with the predictions of the contact mechanics theory by Persson. Theoretical and simulation results agree rather well, and most of the differences observed can be attributed to finite size effects and to the long-range nature of the interaction between the atoms in the block and the substrate in the MD model, as compared to the analytical theory which is for an infinite system with interfacial contact interaction. For curved surfaces (JKR-type of problem) the effective interfacial energy exhibit a weak hysteresis which may be due to the influence of local irreversible detachment processes in the vicinity of the opening crack tip during pull-off.

  19. 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.

  20. Detailed comparative study and a mechanistic model of resuspension of spherical particles from rough and smooth surfaces

    E-Print Network [OSTI]

    Shnapp, Ron

    2014-01-01

    Resuspension of solid particles by a tornado-like vortex from surfaces of different roughness is studied using a three-dimensional particle tracking velocimetry (3D-PTV) method. By utilizing the three-dimensional information on particle positions, velocities and accelerations before, during and after the resuspension (lift-off) event, we demonstrate that the resuspension efficiency is significantly higher from the rough surface, and propose a mechanistic model of this peculiar effect. The results indicate that for all Reynolds numbers tested, the resuspension rate, as well as particle velocities and accelerations, are higher over the rough surface, as compared to the smooth counterpart. The results and the model can help to improve modeling and analysis of resuspension rates in engineering and environmental applications.

  1. Roughness of the SiC/SiO{sub 2} vicinal interface and atomic structure of the transition layers

    SciTech Connect (OSTI)

    Liu, Peizhi; Li, Guoliang; Duscher, Gerd, E-mail: gduscher@utk.edu [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Tennessee 37996 (United States); Sharma, Yogesh K.; Ahyi, Ayayi C.; Isaacs-Smith, Tamara; Williams, John R.; Dhar, Sarit [Department of Physics, Auburn University, Auburn, Alabama 36849 (United States)

    2014-11-01

    The SiC/SiO{sub 2} interface is generally considered to be the cause for the reduced electron mobility of SiC power devices. Previous studies have shown a correlation between the mobility and the transition layer width at the SiC/SiO{sub 2} interface. The authors investigated this interface with atomic resolution Z-contrast imaging and electron energy-loss spectroscopy, and discovered that this transition region was due to the roughness of the vicinal interface. The roughness of a vicinal interface consisted of atomic steps and facets deviating from the ideal off-axis cut plane. The authors conclude that this roughness is limiting the mobility in the channels of SiC MOSFETs.

  2. 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.

  3. 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.

  4. Rotary union for use with ultrasonic thickness measuring probe

    DOE Patents [OSTI]

    Nachbar, Henry D. (Schenectady, NY)

    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.

  5. 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.

  6. Super-spinning compact objects generated by thick accretion disks

    SciTech Connect (OSTI)

    Li, Zilong; Bambi, Cosimo, E-mail: zilongli@fudan.edu.cn, E-mail: bambi@fudan.edu.cn [Center for Field Theory and Particle Physics and Department of Physics, Fudan University, 220 Handan Road, 200433 Shanghai (China)

    2013-03-01

    If astrophysical black hole candidates are the Kerr black holes predicted by General Relativity, the value of their spin parameter must be subject to the theoretical bound |a{sub *}| ? 1. In this work, we consider the possibility that these objects are either non-Kerr black holes in an alternative theory of gravity or exotic compact objects in General Relativity. We study the accretion process when their accretion disk is geometrically thick with a simple version of the Polish doughnut model. The picture of the accretion process may be qualitatively different from the one around a Kerr black hole. The inner edge of the disk may not have the typical cusp on the equatorial plane any more, but there may be two cusps, respectively above and below the equatorial plane. We extend previous work on the evolution of the spin parameter and we estimate the maximum value of a{sub *} for the super-massive black hole candidates in galactic nuclei. Since measurements of the mean radiative efficiency of AGNs require ? > 0.15, we infer the ''observational'' bound |a{sub *}|?<1.3, which seems to be quite independent of the exact nature of these objects. Such a bound is only slightly weaker than |a{sub *}|?<1.2 found in previous work for thin disks.

  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. [CEA Saclay, Irfu/SACM, F-91191 Gif-Sur-Yvette cedex (France); Vinyar, I. [PELIN Limited Liability Company 27 A, Gzhatskaya Str, office 103 St. Petersbourg 195220 (Russian Federation); Relland, J. [CEA Saclay, Irfu/SIS, F-91191 Gif-Sur-Yvette cedex (France); Commeaux, C. [Institut de Physique Nucléaire, campus Universitaire-Bat 103, 91406 Orsay cedex (France)

    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. Bipedal Robotic Walking on Flat-Ground, Up-Slope and Rough Terrain with Human-Inspired Hybrid Zero Dynamics 

    E-Print Network [OSTI]

    Nadubettu Yadukumar, Shishir 1986-

    2012-12-10

    The thesis shows how to achieve bipedal robotic walking on flat-ground, up-slope and rough terrain by using Human-Inspired control. We begin by considering human walking data and find outputs (or virtual constraints) that, when calculated from...

  10. Lattice Boltzmann simulations in microfluidics: probing the no-slip boundary condition in hydrophobic, rough, and surface nanobubble laden microchannels

    E-Print Network [OSTI]

    Jens Harting; Christian Kunert; Jari Hyväluoma

    2009-10-19

    In this contribution we review recent efforts on investigations of the effect of (apparent) boundary slip by utilizing lattice Boltzmann simulations. We demonstrate the applicability of the method to treat fundamental questions in microfluidics by investigating fluid flow in hydrophobic and rough microchannels as well as over surfaces covered by nano- or microscale gas bubbles.

  11. 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.

  12. Effect of edge roughness on electronic transport in graphene nanoribbon channel metal-oxide-semiconductor field-effect transistors

    E-Print Network [OSTI]

    Gilbert, Matthew

    Effect of edge roughness on electronic transport in graphene nanoribbon channel metal-oxide-semiconductor on transport in graphene nanoribbon metal-oxide-semiconductor field-effect transistors MOSFETs are reported of Physics. DOI: 10.1063/1.2839330 Graphene has recently generated considerable interest as a semiconductor

  13. High-order solutions of three-dimensional rough-surface scattering problems at high-frequencies.

    E-Print Network [OSTI]

    Turc, Catalin

    High-order solutions of three-dimensional rough-surface scattering problems at high-frequencies. II with the capability of delivering very accurate results from low to high frequencies at a cost that is independent and polarizations. Submitted to: Waves Random Media #12;High-order high-frequency scattering solutions 2 1

  14. September 15, 2003 / Vol. 28, No. 18 / OPTICS LETTERS 1665 Heat treatment for reduction of surface roughness

    E-Print Network [OSTI]

    Avrutsky, Ivan

    September 15, 2003 / Vol. 28, No. 18 / OPTICS LETTERS 1665 Heat treatment for reduction of surface postdevelopment heat treatment of the photoresist polymer used in the preparation of holographic gratings has been the postdevelopment heat treatment to reduce the surface roughness, the setup shown in Fig. 1 was used. The diffracted

  15. GEOPHYSICAL RESEARCH LETTERS, VOL. 28, NO. 5, PAGES 811-814, MARCH 1, 2001 Parameterizing Tidal Dissipation over Rough

    E-Print Network [OSTI]

    Jayne, Steven

    of barotropic tidal energy. The first line of evidence comes from observations of mix- ing in the abyssal Brazil ocean, the energy flux carried by internal waves generated over rough topog- raphy dominates the energy issues. The first is whether including a parameterization for internal wave energy-flux in a model

  16. 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 1–100cm{sup 3}. The phantom was scanned with different slice thickness (1–10 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 (1–5 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 1–5 mm. The relative decrease in target volume receiving 95% of prescribed dose is ?5% slice thickness change from 1–5 mm. HI increases up to 163% and CI decreases by 4% between 1–5 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.

  17. Thick-Target Neutron Yield from the 19F(alpha,n) Reaction

    E-Print Network [OSTI]

    E. B. Norman; T. E. Chupp; K. T. Lesko; G. L. Woodruff; P. J. Grant

    2015-01-10

    Thick-target neutron yields from the 19F(alpha,n) reaction are reported for E(alpha) = 3.5 - 10.0 MeV.

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. Light trapping and electrical transport in thin-film solar cells with randomly rough Piotr Kowalczewski, Angelo Bozzola, Marco Liscidini, and Lucio Claudio Andreani

    E-Print Network [OSTI]

    Light trapping and electrical transport in thin-film solar cells with randomly rough textures Piotr solar cells J. Appl. Phys. 105, 094511 (2009); 10.1063/1.3108689 Local versus global absorption in thin-film in thin-film solar cells with randomly rough textures Piotr Kowalczewski,a) Angelo Bozzola, Marco

  3. Polyimide-Based Processes for the Fabrication of Thick Electroplated Microstructures

    E-Print Network [OSTI]

    Polyimide-Based Processes for the Fabrication of Thick Electroplated Microstructures Mark G. Allen of polyimide as an electroplating mold for thick electroplated microstructures is discussed. Polyimide of the polyimide material can be performed in a conventional manner, and since the polyimide when cured

  4. DC WRRC Report No. 178 AN EXPERIMENTAL STUDY OF THE OPTIMAL THICKNESS OF A SAND

    E-Print Network [OSTI]

    District of Columbia, University of the

    FILTER WATER QUALITY STRUCTURE July 1994 D.C. Water Resources Research Center University of the District OF THE OPTIMAL THICKNESS OF A SAND LAYER IN A SAND FILTER WATER QUALITY STRUCTURE Submitted by: Farshad Amini THICKNESS OF A SAND LAYER IN A SAND FILTER WATER QUALITY STRUCTURE July 1994 D.C. Water Resources Research

  5. 2009 ASME WIND ENERGY SYMPOSIUM Static and Fatigue Testing of Thick Adhesive Joints for

    E-Print Network [OSTI]

    1 2009 ASME WIND ENERGY SYMPOSIUM Static and Fatigue Testing of Thick Adhesive Joints for Wind as wind blade size has increased. Typical blade joints use paste adhesives several millimeters thick aircraft, which are also of relevance to wind blades in many instances. The strengths of lap-shear and many

  6. Parabolic equation solution of seismo-acoustics problems involving variations in bathymetry and sediment thickness

    E-Print Network [OSTI]

    and sediment thickness Jon M. Collisa and William L. Siegmann Rensselaer Polytechnic Institute110 8th Street within elastic sediment layers. When these methods are implemented together, the parabolic equation method can be applied to problems involving variations in bathymetry and the thickness of sediment layers

  7. Evaluation of Arctic sea ice thickness simulated by Arctic Ocean Model Intercomparison Project models

    E-Print Network [OSTI]

    Zhang, Jinlun

    Evaluation of Arctic sea ice thickness simulated by Arctic Ocean Model Intercomparison Project March 2012. [1] Six Arctic Ocean Model Intercomparison Project model simulations are compared and Assimilation System models. Citation: Johnson, M., et al. (2012), Evaluation of Arctic sea ice thickness

  8. Finite Ground Coplanar Lines on CMOS Grade Silicon with a Thick Embedded Silicon Oxide Layer Using

    E-Print Network [OSTI]

    Tentzeris, Manos

    Finite Ground Coplanar Lines on CMOS Grade Silicon with a Thick Embedded Silicon Oxide Layer Using grade silicon wafer (poxide layer have been developed using on a CMOS grade silicon substrate ( ~ 4 . 0 1Cl-cm) with an embedded thick silicon oxide layer using

  9. LIFE CYCLE ASSESSMENT OF A HEMP CONCRETE WALL: IMPACT OF THICKNESS AND COATING.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    to reduce climate change as photosynthesis-mediated carbon sequestration and carbonation serve to reduce sequestration and carbonation. Moreover the increase in the wall's thermal resistance with wall thickness atmospheric carbon dioxide. A sensitivity analysis is performed on three criteria: wall thickness, renewal

  10. PROCESS ANALYSIS AND SYNTHESIS OF LASER FORMING OF VARYING THICKNESS PLATE

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    of LF varying thickness plate are conducted in this paper. In this paper, the bending mechanism. An analytical model was proposed to predict the bending deformation. A strategy of LF process synthesis-aging the in-plane strain and bending strain. A thickness-dependent da- tabase is established to determine

  11. An Affordable Approach for Robust Design of Thick Laminated Composite Structure

    E-Print Network [OSTI]

    Chen, Wei

    An Affordable Approach for Robust Design of Thick Laminated Composite Structure Wei Chen* Assistant, composite structure design, hip implant #12;3 1. Introduction With a thick laminated composite structure design freedom and the heterogeneous anisotropic nature of structures, composite structures are much more

  12. A modular process for integrating thick polysilicon MEMS devices with sub-micron CMOS

    E-Print Network [OSTI]

    Afshari, Ehsan

    A modular process for integrating thick polysilicon MEMS devices with sub-micron CMOS John-1774 ABSTRACT A new MEMS process module, called Mod MEMS, has been developed to monolithically integrate thick (5-10um), multilayer polysilicon MEMS structures with sub-micron CMOS. This process is particularly

  13. Coating of a stainless steel tube-wall catalytic reactor with thermally treated polysiloxane thick films

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Coating of a stainless steel tube-wall catalytic reactor with thermally treated polysiloxane thick stainless steel by plasma assisted chemical vapour deposition process. Thicknesses up to 10µm were developed barrier. Key-words: PACVD, TDMS, stainless steel, surface passivity. 1. Introduction The use of tube

  14. 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.

  15. The effect of ice crystal surface roughness on the retrieval of ice cloud microphysical and optical properties 

    E-Print Network [OSTI]

    Xie, Yu

    2007-09-17

    ?µm). The discrete ordinates radiative transfer (DISORT) model is used to compute the radiances for a set of optical thicknesses, particle effective sizes, viewing and illumination angles, and cloud temperatures. A parameterization of cloud bi...

  16. 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.

  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, nám. T.G. Masaryka 5555, 760 01 Zlín, 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 Ovcírnou 3685, 760 01 Zlín (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. 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.

  19. Determining the covering factor of Compton-thick active galactic nuclei with NuSTAR

    E-Print Network [OSTI]

    Brightman, M; Stern, D; Arevalo, P; Ballantyne, D R; Bauer, F E; Boggs, S E; Craig, W W; Christensen, F E; Comastri, A; Fuerst, F; Gandhi, P; Hailey, C J; Harrison, F A; Hickox, R C; Koss, M; LaMassa, S; Puccetti, S; Rivers, E; Vasudevan, R; Walton, D J; Zhang, W W

    2015-01-01

    The covering factor of Compton-thick obscuring material associated with the torus in active galactic nuclei (AGN) is at present best understood through the fraction of sources exhibiting Compton-thick absorption along the line of sight ($N_{H}>1.5\\times10^{24}$ cm$^{-2}$) in the X-ray band, which reveals the average covering factor. Determining this Compton-thick fraction is difficult however, due to the extreme obscuration. With its spectral coverage at hard X-rays ($>$10 keV), NuSTAR is sensitive to the AGN covering factor since Compton scattering of X-rays off optically thick material dominates at these energies. We present a spectral analysis of 10 AGN observed with NuSTAR where the obscuring medium is optically thick to Compton scattering, so called Compton-thick (CT) AGN. We use the torus models of Brightman & Nandra which predict the X-ray spectrum from reprocessing in a torus and include the torus opening angle as a free parameter and aim to determine the covering factor of the Compton-thick gas i...

  20. PULSED EDDY CURRENT THICKNESS MEASUREMENT OF SELECTIVE PHASE CORROSION ON NICKEL ALUMINUM BRONZE VALVES

    SciTech Connect (OSTI)

    Krause, T. W.; Harlley, D.; Babbar, V. K.; Wannamaker, K. [Department of Physics, Royal Military College of Canada, Kingston, ON, K7K 7B4 (Canada)

    2010-02-22

    Nickel Aluminum Bronze (NAB) is a material with marine environment applications that under certain conditions can undergo selective phase corrosion (SPC). SPC involves the removal of minority elements while leaving behind a copper matrix. Pulsed eddy current (PEC) was evaluated for determination of SPC thickness on a NAB valve section with access from the surface corroded side. A primarily linear response of PEC amplitude, up to the maximum available SPC thickness of 4 mm was observed. The combination of reduced conductivity and permeability in the SPC phase relative to the base NAB was used to explain the observed sensitivity of PEC to SPC thickness variations.

  1. 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.

  2. 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.

  3. Effective zero-thickness model for a conductive membrane driven by an electric field

    E-Print Network [OSTI]

    Bazant, Martin Z.

    The behavior of a conductive membrane in a static (dc) electric field is investigated theoretically. An effective zero-thickness model is constructed based on a Robin-type boundary condition for the electric potential at ...

  4. 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.

  5. The effect of lubrication film thickness on thermoelastic instability under fluid lubricating condition

    E-Print Network [OSTI]

    Yi, Yun-Bo

    The effect of lubrication film thickness on thermoelastic instability under fluid lubricating online 14 March 2013 Keywords: Thermoelastic instability Wet clutches Fluid lubrication Critical speed by a thin layer of lubricating fluid is developed to investigate thermoelastic instability with fluid

  6. Thickness of the crust of Mercury from geoid-to-topography ratios

    E-Print Network [OSTI]

    Padovan, S; Wieczorek, MA; Margot, JL; Tosi, N; Solomon, SC

    2015-01-01

    the support of planetary topography, J. Geophys. Res. , 86,thickness and support of topography on Venus, J. Geophys.expansion for the topography of Mercury, GTMES_120V02_SHA,

  7. Oxide thickness measurement technique for duplex-layer Zircaloy-4 cladding

    SciTech Connect (OSTI)

    McClelland, R.G.; O'Leary, P.M. (Siemens Nuclear Power Corp., Richland, WA (United States))

    1992-01-01

    Siemens Nuclear Power Corporation (SNP) is investigating the use of duplex-layer Zircaloy-4 tubing to improve the waterside corrosion resistance of cladding for high-burnup pressurized water reactor (PWR) fuel designs. Standard SNP PWR cladding is typically 0.762-mm (0.030-in.)-thick Zircaloy-4. The SNP duplex cladding is nominally 0.660-mm (0.026-in.)-thick Zircalloy-4 with an [approximately]0.102-mm (0.004-in.) outer layer of another, more corrosion-resistant, zirconium-based alloy. It is common industry practice to monitor the in-reactor corrosion behavior of Zircaloy cladding by using an eddy-current lift-off' technique to measure the oxide thickness on the outer surface of the fuel cladding. The test program evaluated three different cladding samples, all with the same outer diameter and wall thickness: Zircaloy-4 and duplex clad types D2 and D4.

  8. A determination of the effective thickness of a liquid deuterium target for a quasielastic scattering experiment

    E-Print Network [OSTI]

    Turkewitz, Jared Ripley

    2010-01-01

    The effective thickness of a liquid deuterium target was determined by measuring the yield of the neutron-deuteron elastic scattering cross section. The flux of incident neutrons was determined by a fission ionization ...

  9. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica

    E-Print Network [OSTI]

    Fretwell, P.; Pritchard, H. D.; Vaughan, D. G.; Bamber, J. L.; Barrand, N. E.; Bell, R.; Bianchi, C.; Bingham, R. G.; Blankenship, D. D.; Casassa, G.; Catania, G.; Callens, D.; Conway, H.; Cook, A. J.; Corr, H. F. J.; Damaske, D.; Damm, V.; Ferraccioli, F.; Forsberg, R.; Fujita, S.; Gim, Y.; Gogineni, Sivaprasad; Griggs, J. A.; Hindmarsh, R.; Holmlund, P.; Holt, J. W.; Jacobel, R. W.; Jenkins, A.; Jokat, W.; Jordan, T.; King, E. C.; Kohler, J.; Krabill, W.; Riger-Kusk, M.; Langley, K. A.; Leitchenkov, G.; Leuschen, Carl; Lyendyk, B. P.; Matsuoka, K.; Mouginot, J.; Nitsche, F. O.; Nogi, Y.; Nost, O. A.; Popov, S. V.; Rignot, E.; Rippin, D. M.; Rivera, A.; Roberts, J.; Roberts, J.; Ross, N.; Siegert, M. J.; Smith, A. M.; Steinhage, D.; Studinger, M.; Sun, B.; Tinto, B. K.; Welch, B. C.; Wilson, D.; Young, D. A.; Xiangbin, C.; Zirizzotti, A.

    2013-02-28

    We present Bedmap2, a new suite of gridded products describing surface elevation, ice-thickness and the seafloor and subglacial bed elevation of the Antarctic south of 60° S. We derived these products using data from a ...

  10. Analysis of Antarctic Sea Ice Thickness: A Newly Created Database for 2000-2009 

    E-Print Network [OSTI]

    Morgan, Benjamin Patrick

    2012-10-19

    Observations of Antarctic sea ice thickness are sporadic in space and time, hindering knowledge of its variability. A proxy based on stage of development data from the National Ice Center (NIC) weekly operational charts is used to create a high...

  11. Thickness Measurement of Fracture Fluid Gel Filter Cake after Static Build Up and Shear Erosion 

    E-Print Network [OSTI]

    Xu, Ben

    2011-08-08

    . Despite proven economic benefit, the hydraulic fracture fluid damages the producing formation and the propped fracture. To analyze the gel damage effect quantitatively, the filter cake thickness is used as a parameter that has not been measured before...

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

    Office of Scientific and Technical Information (OSTI)

    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...

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

    Office of Scientific and Technical Information (OSTI)

    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...

  14. Searching for the metal-weak thick disc in the solar neighbourhood

    E-Print Network [OSTI]

    Bacham E. Reddy; David L. Lambert

    2008-09-05

    An abundance analysis is presented of 60 metal-poor stars drawn from catalogues of nearby stars provided by Ariyanto et al. (2005) and Schuster et al. (2006). In an attempt to isolate a sample of metal-weak thick disc stars, we applied the kinematic criteria $V_{\\rm rot} \\geq 100$ km s$^{-1}$, $|U_{LSR}| \\leq 140$ km s$^{-1}$, and $|W_{LSR}| \\leq 100$ km s$^{-1}$. Fourteen stars satisfying these criteria and having [Fe/H] $\\leq -1.0$ are included in the sample of 60 stars. Eight of the 14 have [Fe/H] $\\geq -1.3$ and may be simply thick disc stars of slightly lower than average [Fe/H]. The other six have [Fe/H] from -1.3 to -2.3 and are either metal-weak thick disc stars or halo stars with kinematics mimicking those of the thick disc. The sample of 60 stars is completed by eight thick disc stars, 20 stars of a hybrid nature (halo or thick disc stars), and 18 stars with kinematics distinctive of the halo.

  15. LOW ALLOY STEELS FOR THICK WALL PRESSURE VESSELS Yearly Report for Period Oct. 1, 1976 to Sept. 30, 1977.

    E-Print Network [OSTI]

    Horn, R.M.

    2011-01-01

    FOR THICK WALL PRESSURE VESSELS R. M, Horn, E. R. Parker,FOR THICK WALL PRESSURE VESSELS Yearly Report f o r PeriodManufacture Pressure Vessel Fabrication Under ASME Code

  16. Invertebrate muscles: Thin and thick filament structure; molecular basis of contraction and its regulation, catch and asynchronous muscle

    E-Print Network [OSTI]

    Hooper, Scott

    Invertebrate muscles: Thin and thick filament structure; molecular basis of contraction and its . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 2.1. Vertebrate thin and thick filament structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 2.2. Cross-bridge driven filament sliding underlies force production

  17. Experimental and Computational Study of the Effect of the System Size on Rough Surfaces Formed by Sedimenting Particles in Quasi-Two-Dimensions

    E-Print Network [OSTI]

    K. V. McCloud; U. Cardak; M. L. Kurnaz

    2004-08-22

    The roughness exponent of surfaces obtained by dispersing silica spheres into a quasi-two-dimensional cell is examined using experimental and computational methods. The cell consists of two glass plates separated by a gap, which is comparable in size to the diameter of the beads. We have studied the effect of changing the gap between the plates to a limit of about twice the diameter of the beads. If the conventional scaling analysis is performed, the roughness exponent is found to be robust against changes in the gap between the plates. The surfaces formed have two roughness exponents in two length scales, which have a crossover length about 1 cm.; however, the computational results do not show the same crossover behavior. The single exponent obtained from the simulations stays between the two roughness exponents obtained in the experiments.

  18. On the Emissivity of Silver Coated Panels, Effect of Long Term Stability and Effect of Coating Thickness

    E-Print Network [OSTI]

    On the Emissivity of Silver Coated Panels, Effect of Long Term Stability and Effect of Coating Thickness

  19. 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 (4?M{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.

  20. Uniqueness of RS2 type thick branes supported by a scalar field

    E-Print Network [OSTI]

    S. T. Abdyrakhmanov; K. A. Bronnikov; B. E. Meierovich

    2005-03-13

    We study thick brane world models as Z_2-symmetric domain walls supported by a scalar field with an arbitrary potential V(\\phi) in 5D general relativity. Under the global regularity requirement, such configurations (i) have always an AdS asymptotic far from the brane, (ii) are only possible if V(\\phi) has an alternating sign and (iii) V(\\phi) should satisfy a certain fine-tuning type equality. Thus a thick brane with any admissible V(\\phi) is a regularized version of the RS2 brane immersed in the AdS_5 bulk. The thin brane limit is realized in a universal manner by including an arbitrary thick brane model in a one-parameter family, where the parameter "a" is associated with brane thickness; the asymptotic value of V(\\phi) (related to \\Lambda_5, the effective cosmological constant) remains a-independent. The problem of ordinary matter confinement on the brane is discussed for a test scalar field. Its stress-energy tensor is found to diverge at the AdS horizon for both thin and thick branes, making a serious problem for this class of brane world models.

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

    DOE Patents [OSTI]

    Wickboldt, Paul (Walnut Creek, CA); Ellingboe, Albert R. (Fremont, CA); Theiss, Steven D. (Woodbury, MN); Smith, Patrick M. (San Ramon, CA)

    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.

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

    DOE Patents [OSTI]

    Jackson, Theodore (Atlanta, GA); Hall, Maclin S. (Marietta, GA)

    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.

  3. Origin of chemical and dynamical properties of the Galactic thick disk

    E-Print Network [OSTI]

    Bekki, Kenji

    2011-01-01

    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 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 ...

  4. Jeans analysis of the Galactic thick disk and the local dark matter density

    E-Print Network [OSTI]

    Sanchez-Salcedo, F J; de Diego, J A

    2015-01-01

    Dynamical estimates of the mass surface density at the solar radius can be made up to a height of 4 kpc using thick disk stars as tracers of the potential. We investigate why different Jeans estimators of the local surface density lead to puzzling and conflicting results. Using the Jeans equations, we compute the vertical (F_z) and radial (F_R) components of the gravitational force, as well as Gamma(z), defined as the radial derivative of V_c^2, with V_c^{2}= -RF_R. If we assume that the thick disk does not flare and that all the components of the velocity dispersion tensor of the thick disk have a uniform radial scalelength of 3.5 kpc, Gamma takes implausibly large negative values, when using the currently available kinematical data of the thick disk. This implies that the input parameters or the model assumptions must be revised. We have explored, using a simulated thick disk, the impact of the assumption that the scale lengths of the density and velocity dispersions do not depend on the vertical height z a...

  5. 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 variablemore »range 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

  6. Limits on thickness and efficiency of Polish Doughnuts in application to the ULX sources

    E-Print Network [OSTI]

    Wielgus, Maciek; Lasota, Jean-Pierre; Abramowicz, Marek

    2015-01-01

    Polish Doughnuts (PDs) are geometrically thick disks which rotate with super-Keplerian velocities in their innermost parts, and whose long and narrow funnels along rotation axes collimate the emerging radiation into beams. In this paper we construct extremal family of PDs that maximize both geometrical thickness and radiative efficiency. We then derive upper limits for these quantities and subsequently for the related ability to collimate radiation. PDs with such extreme properties may explain the observed properties of the ULX sources with no need for the black hole masses exceeding ~ 10 solar masses. However, we show that strong advective cooling, which is expected to be one of the dominant cooling mechanisms in accretion flows with super-Eddington accretion rates, tends to reduce geometrical thickness and luminosity of PDs substantially. We also show that the beamed radiation emerging from the PDs' funnels corresponds to "isotropic" luminosities that linearly scale with the mass accretion rate, and do not ...

  7. 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 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 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

  8. Thick Pb(Zr,Ti)O{sub 3} film without substrate

    SciTech Connect (OSTI)

    Lee, Jae-Wung; Park, Chee-Sung; Jo, Ji-Hoon; Kim, Hyoun-Ee [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2007-08-13

    In order to fabricate thick PbZr{sub x}Ti{sub 1-x}O{sub 3} (PZT) films for microelectromechanical system applications, the authors introduce a concept of freestanding film without a substrate. PZT films with a thickness of up to 20 {mu}m were deposited on a very thin Pt layer without a substrate by the rf-magnetron sputtering method using a single oxide target. The Pt layer (thickness <1 {mu}m) was obtained by sputtering the Pt on a Si substrate with a carbon layer between them, and subsequently removing the carbon layer by oxidation in air at 400 deg. C. Piezoelectric properties of the film were comparable to those of bulk PZT as a result of the removal of clamping effect of the substrate.

  9. 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.

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

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

    Shen, Xuan [Nanjing Univ. (China); Brookhaven National Lab. (BNL), Upton, NY (United States); Qiu, Xiangbiao [Nanjing Univ. (China); Su, Dong [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhou, Shengqiang [Inst. of Ion Beam Physics and Materials Research, Dresden (Germany); Li., Aidong [Nanjing Univ. (China); Wu, Di [Nanjing Univ. (China)

    2015-01-07

    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. Magnetoresistance measurements reveal a likely magnetic anisotropy with the magnetic easy axis along the out-of-plane direction.

  11. 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.

  12. Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

    E-Print Network [OSTI]

    R. Alba; M. Barbagallo; P. Boccaccio; A. Celentano; N. Colonna; G. Cosentino; A. Del Zoppo; A. Di Pietro; J. Esposito; P. Figuera; P. Finocchiaro; A. Kostyukov; C. Maiolino; M. Osipenko; G. Ricco; M. Ripani; C. M. Viberti; D. Santonocito; M. Schillaci

    2012-08-08

    In the framework of research on IVth generation reactors and high intensity neutron sources a low-power prototype neutron amplifier was recently proposed by INFN. It is based on a low-energy, high current proton cyclotron, whose beam, impinging on a thick Beryllium converter, produces a fast neutron spectrum. The world database on the neutron yield from thick Beryllium target in the 70 MeV proton energy domain is rather scarce. The new measurement was performed at LNS, covering a wide angular range from 0 to 150 degrees and an almost complete neutron energy interval. In this contribution the preliminary data are discussed together with the proposed ADS facility.

  13. 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.

  14. Influence of wall thickness on the stability of the resistive wall mode in tokamak Richard Fitzpatrick

    E-Print Network [OSTI]

    Fitzpatrick, Richard

    Influence of wall thickness on the stability of the resistive wall mode in tokamak plasmas Richard.1063/1.2446041 Nonlinear evolution of resistive wall mode in a cylindrical tokamak with poloidal rotation Phys. Plasmas 13); 10.1063/1.1943347 Control of resistive wall modes in a cylindrical tokamak with radial and poloidal

  15. Micro-fabrication of high-thickness spiral inductors for the remote powering of implantable biosensors

    E-Print Network [OSTI]

    De Micheli, Giovanni

    biosensors Jacopo Olivo , Sandro Carrara, Giovanni De Micheli Integrated Circuits Laboratory, EPFL ­ École Keywords: High-thickness inductors Inductive link Remote powering Implantable biosensors Ordyl a b s t r for the remote power- ing of implantable biosensors through inductive link. The process is suitable for different

  16. INFLUENCE OF HYDRIDE MICROSTRUCTURE ON THROUGH-THICKNESS CRACK GROWTH IN ZIRCALOY-4 SHEET

    E-Print Network [OSTI]

    Motta, Arthur T.

    1 INFLUENCE OF HYDRIDE MICROSTRUCTURE ON THROUGH-THICKNESS CRACK GROWTH IN ZIRCALOY-4 SHEET P. A and Engineering, The Pennsylvania State University, University Park, PA 16802 2 Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802 3 Southwest Research

  17. Estimation of the optical constants and the thickness of thin lms using unconstrained

    E-Print Network [OSTI]

    Martínez, José Mario

    Estimation of the optical constants and the thickness of thin #12;lms using unconstrained, spectral gradient method, optical constants, thin #12;lms. 1 #12; Proposed running head: Estimation of optical constants of thin #12;lms using SGM Corresponding author: Jos#19;e Mario Mart#19;#16;nez

  18. Created 12/8/05 Nanospec / AFT Film Thickness Measurement System

    E-Print Network [OSTI]

    objective and refocus. d. Critical Focus required for film thickness suspected to be Control knob until the Photo Intensity Meter reads between 65.0 and 67.0. a. Gain Control knob located in the open back of the cover. DO NOT ADJUST "ZERO", located to the left of GAIN. b. Photo Intensity Meter

  19. The imprints of the Galactic bar on the thick disk with RAVE

    E-Print Network [OSTI]

    Antoja, T; Helmi, A; Bienaymé, O; Bland-Hawthorn, J; Famaey, B; Gibson, B K; Grebel, E K; Kordopatis, G; Munari, U; Navarro, J; Parker, Q; Reid, W A; Seabroke, G; Steinmetz, M; Zwitter, T

    2015-01-01

    We study the kinematics of a local sample of stars, located within a cylinder of 500 pc radius centered on the Sun, in the RAVE dataset. We find clear asymmetries in the $v_R$-$v_\\phi$ velocity distributions of thin and thick disk stars: here are more stars moving radially outwards for low azimuthal velocities and more radially inwards for high azimuthal velocities. Such asymmetries have been previously reported for the thin disk as being due to the Galactic bar, but this is the first time that the same type of structures are seen in the thick disk. Our findings imply that the velocities of thick disk stars should no longer be described by Schwarzschild's, multivariate Gaussian or purely axisymmetric distributions. Furthermore, the nature of previously reported substructures in the thick disk needs to be revisited as these could be associated with dynamical resonances rather than to accretion events. It is clear that dynamical models of the Galaxy must fit the 3D velocity distributions of the disks, rather th...

  20. Static and fatigue bending behavior of pultruded GFRP sandwich panels with through-thickness fiber insertions

    E-Print Network [OSTI]

    Static and fatigue bending behavior of pultruded GFRP sandwich panels with through-thickness fiber testing a b s t r a c t This paper presents the findings of a research program that was undertaken to evaluate the effective elastic modulus, shear modulus and degree of composite interaction of the panels

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

    SciTech Connect (OSTI)

    Nelson, Andrew T. [Los Alamos National Laboratory

    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.

  2. Study of Dislocation Densities Through the Thickness of 7050 Aluminum Cory Parker, David Field

    E-Print Network [OSTI]

    Collins, Gary S.

    Study of Dislocation Densities Through the Thickness of 7050 Aluminum Cory Parker, David Field WSU number DMR-1062898. Introduction 7050 Aluminum is a lightweight, yet strong, alloy primarily used rather difficult due to the presence of a wide range of particles in the substrate. 7050 goes through

  3. 18 m THICK HIGH FREQUENCY CAPACITIVE HARPSS RESONATORS WITH REDUCED MOTIONAL RESISTANCE

    E-Print Network [OSTI]

    Ayazi, Farrokh

    thermal oxide layer is first grown on the low resistivity SOI substrate. The oxide is patterned and kept be as large as a few tens of microns. Trench sidewalls are coated with a thin sacrificial LPCVD oxide layer. The thickness of the deposited sacrificial oxide layer determines the capacitive gap size in between the SCS

  4. 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.

  5. 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.

  6. Altering Anode Thickness To Improve Power Production in Microbial Fuel Cells with Different Electrode Distances

    E-Print Network [OSTI]

    Altering Anode Thickness To Improve Power Production in Microbial Fuel Cells with Different ABSTRACT: A better understanding of how anode and separator physical properties affect power production is needed to improve energy and power production by microbial fuel cells (MFCs). Oxygen crossover from

  7. Embedding metal electrodes in thick active layers for ITO-free plasmonic organic solar cells

    E-Print Network [OSTI]

    Park, Namkyoo

    Embedding metal electrodes in thick active layers for ITO-free plasmonic organic solar cells%) in optical absorption over both a conventional ITO organic solar cell and a conventional plasmonic organic solar cell with top-loaded metallic grating is predicted in the proposed structure. Optimal positioning

  8. 15.7% Efficient 10-?m-Thick Crystalline Silicon Solar Cells Using Periodic Nanostructures

    E-Print Network [OSTI]

    Branham, Matthew Sanders

    Only ten micrometer thick crystalline silicon solar cells deliver a short-circuit current of 34.5 mA cm[superscript ?2] and power conversion efficiency of 15.7%. The record performance for a crystalline silicon solar cell ...

  9. Growth Termination of Carbon Nanotubes at Millimeter Thickness Due to Structural Change in Catalyst

    E-Print Network [OSTI]

    Maruyama, Shigeo

    Growth Termination of Carbon Nanotubes at Millimeter Thickness Due to Structural Change in Catalyst, it is reported that "supergrowth" rate decreases with reaction time and finally the growth terminates [2]. Our group recently reproduced "supergrowth" [3] and observed similar "supergrowth" termination within a few

  10. Optical Histology: A Method to Visualize Microvasculature in Thick Tissue Sections of Mouse Brain

    E-Print Network [OSTI]

    Rose, Michael R.

    Optical Histology: A Method to Visualize Microvasculature in Thick Tissue Sections of Mouse Brain% paraformaldehyde. The organ is then sliced into 1 mm sections and optically cleared, or made transparent, using FocusClear, a proprietary optical clearing agent. After optical clearing, the DiI-labeled tissue

  11. Aperture Synthesis Observations of the Nearby Spiral NGC 6503: Modeling the Thin and Thick HI Disks

    E-Print Network [OSTI]

    Greisen, Eric

    Aperture Synthesis Observations of the Nearby Spiral NGC 6503: Modeling the Thin and Thick HI Disks aperture synthesis observations of the nearby, late­type spiral galaxy NGC 6503, and produce HI maps field, while remarkably regular, contains clear evidence for irregularities. The HI is distributed over

  12. Aperture Synthesis Observations of the Nearby Spiral NGC 6503: Modeling the Thin and Thick HI Disks

    E-Print Network [OSTI]

    Greisen, Eric

    Aperture Synthesis Observations of the Nearby Spiral NGC 6503: Modeling the Thin and Thick HI Disks aperture synthesis observations of the nearby, late-type spiral galaxy NGC 6503, and produce HI maps field, while remarkably regular, contains clear evidence for irregularities. The HI is distributed over

  13. Finite Element Analysis of Nonlinear Thickness-shear Vibrations of AT-cut Quartz Crystal Plates

    E-Print Network [OSTI]

    Wang, Ji

    Finite Element Analysis of Nonlinear Thickness-shear Vibrations of AT-cut Quartz Crystal Plates Ji, dujianke}@nbu.edu.cn Abstract--The nonlinear finite element analysis is performed with the nonlinear a smaller size in comparison with the 3D approach. General procedure of nonlinear finite element analysis

  14. Reprocessed emission line profiles from dense clouds in geometrically thick accretion engines

    E-Print Network [OSTI]

    Sean A. Hartnoll; Eric G. Blackman

    2000-09-19

    The central engines of active galactic nuclei (AGN) contain cold, dense material as well as hot X-ray emitting gas. The standard paradigm for the engine geometry is a cold thin disc sandwiched between hot X-ray coronae. Strong support for this geometry in Seyferts comes from the study of fluorescent iron line profiles, although the evidence is not ubiquitously air tight. The thin disc model of line profiles in AGN and in X-ray binaries should be bench marked against other plausible possibilities. One proposed alternative is an engine consisting of dense clouds embedded in an optically thin, geometrically thick X-ray emitting engine. This model is further motivated by studies of geometrically thick engines such as advection dominated accretion flows (ADAFs). Here we compute the reprocessed iron line profiles from dense clouds embedded in geometrically thick, optically thin X-ray emitting discs near a Schwarzchild black hole. We consider a range of cloud distributions and disc solutions, including ADAFs, pure radial infall, and bipolar outflows. We find that such models can reproduce line profiles similar to those from geometrically thin, optically thick discs and might help alleviate some of the problems encountered from the latter.

  15. Light Trapping Textures Designed by Electromagnetic Optimization for Sub-Wavelength Thick Solar Cells

    E-Print Network [OSTI]

    California at Irvine, University of

    the surface of the solar cell, where n is the material refractive index. This ray-optics absorption enhancement limit only holds when the thickness of the solar cell is much greater than the optical wavelength limit of 4n2 50. Introduction Texturing of solar cell surfaces allows for absorption enhancement, owing

  16. Research Paper Quantitative Image Analysis for Evaluating the Coating Thickness and Pore

    E-Print Network [OSTI]

    van Vliet, Lucas J.

    Research Paper Quantitative Image Analysis for Evaluating the Coating Thickness and Pore Distribution in Coated Small Particles F. L. Laksmana,1,3,5 L. J. Van Vliet,2 P. J. A. Hartman Kok,3 H. Vromans method for coating structure based on image analysis, which is particularly promising for the rational

  17. A 3D Volumetric Laplace-Beltrami Operator based Cortical Thickness Estimation Method

    E-Print Network [OSTI]

    Wang, Yalin

    A 3D Volumetric Laplace-Beltrami Operator based Cortical Thickness Estimation Method Gang Wanga the cortical tetrahedral mesh, we adopt the heat kernel [1] based on volumetric Laplace-Beltrami operator can construct the discrete volumetric Laplace-Beltrami operator under the Dirichlet boundary condition

  18. Modelling volumetric growth in a thick walled fibre reinforced artery T.S.E. Erikssona,

    E-Print Network [OSTI]

    Luo, Xiaoyu

    Modelling volumetric growth in a thick walled fibre reinforced artery T.S.E. Erikssona, , P a combination of both AID and CID to simulate volumetric G&R for a tissue comprised of several different arterial biology. For simulating the volumetric changes that occur during aneurysm enlargement, we observe

  19. Density slope of the nuclear symmetry energy from the neutron skin thickness of heavy nuclei 

    E-Print Network [OSTI]

    Chen, Lie-Wen; Ko, Che Ming; Li, Bao-An; Xu, Jun.

    2010-01-01

    of finite nuclei and nuclear matter properties. We find that existing data on neutron skin thickness Delta r(np) of Sn isotopes give an important constraint on the symmetry energy E(sym)(rho(0)) and its density slope L at saturation density rho(0). Combining...

  20. Simulation studies of hadron energy resolution as a function of iron plate thickness at INO-ICAL

    E-Print Network [OSTI]

    Lakshmi S. Mohan; Anushree Ghosh; Moon Moon Devi; Daljeet Kaur; Sandhya Choubey; Amol Dighe; D. Indumathi; M. V. N. Murthy; Md. Naimuddin

    2015-03-11

    We report on a detailed simulation study of the hadron energy resolution as a function of the thickness of the absorber plates for the proposed Iron Calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO). We compare the hadron resolutions obtained with absorber thicknesses in the range 1.5--8 cm for neutrino interactions in the energy range 2--15 GeV, which is relevant to hadron production in atmospheric neutrino interactions. We find that at lower energies, the thickness dependence of energy resolution is steeper than at higher energies, however there is a thickness-independent contribution that dominates at the lower thicknesses discussed in this work. As a result, the gain in hadron energy resolution with decreasing plate thickness is marginal. We present the results in the form of fits to a function with energy-dependent exponent.

  1. 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.

  2. 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.

  3. 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.

  4. A Thickness of Stellar Disks of Edge-on Galaxies and Position of Their Truncation Radii

    E-Print Network [OSTI]

    A. V. Zasov; D. V. Bizyaev

    2002-12-13

    The relationship between the geometrical properties of stellar disks (a flatness and truncation radius) and the disk kinematics are considered for edge-on galaxies. It is shown that the observed thickness of the disks and the approximate constancy of their thickness along the radius well agrees with the condition of their marginal local gravitational stability. As a consequence, those galaxies whose disks are thinner should harbor more massive dark haloes. The correlation between the de-projeced central brightness of the disks and their flatness is found (the low surface brightness disks tend to be the thinniest ones). We also show that positions of observed photometrically determined truncation radii $R_{cut}$ for the stellar disks support the idea of marginal local gravitational stability of gaseous protodisks at $R =R_{cut}$, and hence the steepening of photometric profiles may be a result of too inefficient star formation beyond $R_{cut}$.

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

    DOE Patents [OSTI]

    Henager, Jr., Charles H. (Kennewick, WA); Knoll, Robert W. (Menomonee Falls, WI)

    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. Fabrication and Test of Pixelated CZT Detectors with Different Pixel Pitches and Thicknesses

    E-Print Network [OSTI]

    Q. Li; A. Garson; P. Dowkontt; J. Martin; M. Beilicke; I. Jung; M. Groza; A. Burger; G. De Geronimo; H. Krawczynski; .; .; .; .

    2008-11-19

    The main methods grown Cadmium Zinc Telluride (CZT) crystals with high yield and excellent homogeneity are Modified Horizontal Bridgman (MHB) and High Pressure Bridgman (HPB) processes, respectively. In this contribution, the readout system based on two 32-channel NCI-ASICs for pixellated CZT detector arrays has been developed and tested. The CZT detectors supplied by Orbotech (MHB) and eV products (HPB) are tested by NCI-ASIC readout system. The CZT detectors have an array of 8x8 or 11x11 pixel anodes fabricated on the anode surface with the area up to 2 cm x2 cm and the thickness of CZT detectors ranges from 0.5 cm to 1 cm. Energy spectra resolution and electron mobility-lifetime products of 8x8 pixels CZT detector with different thicknesses have been investigated.

  7. Standard guide for mutual inductance bridge applications for wall thickness determinations in boiler tubing

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This guide describes a procedure for obtaining relative wall thickness indications in ferromagnetic and non-ferromagnetic steels using the mutual inductance bridge method. The procedure is intended for use with instruments capable of inducing two substantially identical magnetic fields and noting the change in inductance resulting from differing amounts of steel. It is used to distinguish acceptable wall thickness conditions from those which could place tubular vessels or piping at risk of bursting under high temperature and pressure conditions. 1.2 This guide is intended to satisfy two general needs for users of industrial Mutual Inductance Bridge (MIB) equipment: (1) the need for a tutorial guide addressing the general principles of Mutual Inductance Bridges as they apply to industrial piping; and (2) the need for a consistent set of MIB performance parameter definitions, including how these performance parameters relate to MIB system specifications. Potential users and buyers, as well as experienced M...

  8. Thickness Measurements from Single X-ray Phase-contrast Speckle Projection

    E-Print Network [OSTI]

    Xi, Yan; Ma, Jingchen; Zhao, Jun

    2015-01-01

    We propose a one-shot thickness measurement method for sponge-like structures using a propagation-based X-ray phase-contrast imaging (P-PCI) method. In P-PCI, the air-material interface refracts the incident X-ray. Refracted many times along their paths by such a structure, incident X-rays propagate randomly within a small divergent angle range, resulting in a speckle pattern in the captured image. We found structure thickness and contrast of a phase-contrast projection are directly related in images. This relationship can be described by a natural logarithm equation. Thus, from the one phase-contrast view, depth information can be retrieved from its contrast. Our preliminary biological experiments indicate promise in its application to measurements requiring in vivo and ongoing assessment of lung tumor progression.

  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% 80–20, 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. Plasmonic finite-thickness metal-semiconductor-metal waveguide as ultra-compact modulator

    E-Print Network [OSTI]

    Babicheva, Viktoriia E; Lavrinenko, Andrei V

    2013-01-01

    We propose a plasmonic modulator with semiconductor gain material for optoelectronic integrated circuits. We analyze properties of a finite-thickness metal-semiconductor-metal (F-MSM) waveguide to be utilized as an ultra-compact and fast plasmonic modulator. The InP-based semiconductor core allows electrical control of signal propagation. By pumping the core we can vary the gain level and thus the transmittance of the whole system. The study of the device was made using both analytical approaches for planar two-dimensional case as well as numerical simulations for finite-width waveguides. We analyze the eigenmodes of the F-MSM waveguide, propagation constant, confinement factor, Purcell factor, absorption coefficient, and extinction ratio of the structure. We show that using thin metal layers instead of thick ones we can obtain higher extinction ratio of the device.

  11. 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.

  12. Development of low frequencies, insulating thick diaphragms for power MEMS applications

    E-Print Network [OSTI]

    Formosa, Fabien; Favrelière, Hugues; 10.1016/j.sna.2012.09.018

    2013-01-01

    Major challenges of micro thermal machines are the thermal insulation and mechanical tolerance in the case of sliding piston. Switching from piston to membrane in microengines can alleviate the latest and lead to planar architectures. However, the thermal isolation would call for very thick structures which are associated to too high resonant frequencies which are detrimental to the engine performances. A thermal and mechanical compromise is to be made. On the contrary, based on fluid structure interaction, using an incompressible fluid contained in a cavity sealed by deformable diaphragm it would be possible to design a thick, low frequency insulating diaphragm. The design involves a simple planar geometry that is easy to manufacture with standard microelectronics methods. An analytical fluid structure model is proposed and theoretically validated. Experimental structures are realized and tested. The model is in agreement with the experimental results. A dimensionless model is proposed to design hybrid fluid...

  13. Has a thick neutron skin in ${}^{208}$Pb been ruled out?

    E-Print Network [OSTI]

    Fattoyev, F J

    2013-01-01

    The Lead Radius Experiment (PREX) has provided the first model-independent evidence in favor of a neutron-rich skin in ${}^{208}$Pb. Although the error bars are large, the reported large central value of 0.33\\,fm is particularly intriguing. To test whether such a thick neutron-skin in ${}^{208}$Pb is already incompatible with laboratory experiments or astrophysical observations, we employ relativistic models with neutron-skin thickness in ${}^{208}$Pb ranging from 0.16 to 0.33 fm to compute ground state properties of finite nuclei, their collective monopole and dipole response, and mass-{\\sl vs}-radius relations for neutron stars. No compelling reason was found to rule out models with large neutron skins in ${}^{208}$Pb from the set of observables considered in this work.

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

    DOE Patents [OSTI]

    Wang, Qi (Littleton, CO); Stradins, Paul (Golden, CO); Teplin, Charles (Boulder, CO); Branz, Howard M. (Boulder, CO)

    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.

  15. 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.

  16. 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.

  17. 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.

  18. COMPARISON OF SEA SURFACE ROUGHNESS MODELS FOR OFFSHORE WIND POWER UTILISATION Bernhard Lange(1), Jrgen Hjstrup(2), Sren Larsen(2), Rebecca Barthelmie(2)

    E-Print Network [OSTI]

    Heinemann, Detlev

    COMPARISON OF SEA SURFACE ROUGHNESS MODELS FOR OFFSHORE WIND POWER UTILISATION Bernhard Lange(1 Large offshore wind farms are being built in several countries in Europe. The economic viability of such projects depends on the favourable wind conditions of offshore sites, since the higher energy yield has

  19. 44 IEEE TRANSACTIONS ON ELECTRONICS PACKAGING MANUFACTURING, VOL. 24, NO. 1, JANUARY 2001 Rough Set Theory: A Data Mining Tool for

    E-Print Network [OSTI]

    Kusiak, Andrew

    Theory: A Data Mining Tool for Semiconductor Manufacturing Andrew Kusiak, Member, IEEE Abstract of data. Data mining has emerged as a discipline that contributes tools for data analysis, discovery and other aspects of data mining are introduced. The rough set theory offers a viable approach

  20. Suppression of thermal conductivity in graphene nanoribbons with rough edges Alexander V. Savin,1,2 Yuri S. Kivshar,2 and Bambi Hu3,4

    E-Print Network [OSTI]

    , Moscow 119991, Russia 2Nonlinear Physics Center, Research School of Physics and Engineering, Australian, the thermal properties of graphene are also of both fundamental and practical im- portance. SeveralSuppression of thermal conductivity in graphene nanoribbons with rough edges Alexander V. Savin,1

  1. Using seismic refraction to assess geothermal potential: an updated view of crustal thickness in the Great Basin

    E-Print Network [OSTI]

    , heat flow can be higher, and the potential for geothermal energy may be greater. In addition, crustalUsing seismic refraction to assess geothermal potential: an updated view of crustal thickness, Great Basin, crustal thickness, geothermal potential, Battle Mountain, Walker Lane, Nevada, geophysics

  2. Thickness-dependent changes in the optical properties of PPV-and PF-based polymer light emitting diodes

    E-Print Network [OSTI]

    Carter, Sue

    the thickness-dependent optical properties of single layer polymer light emitting diodes for two materials, poly the electronic and optical properties of these materials in light emitting diode LED structures.2 OurThickness-dependent changes in the optical properties of PPV- and PF-based polymer light emitting

  3. Abstract--In this paper, the propagation characteristics of an enhanced-thickness magnetic nanoparticle thin film are

    E-Print Network [OSTI]

    Tentzeris, Manos

    nanoparticle thin film are investigated on high resistivity silicon substrate (10,000 ohm-cm) for the first time up to 60 GHz. Contrary to other thin films, this nanoparticle thin film can achieve a thickness up to several hundred nanometers, even to micron. The enhanced thickness of this thin film is achieved

  4. 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 [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)] [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

    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.

  5. 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.

  6. Improved gas sensing and dielectric properties of Fe doped hydroxyapatite thick films: Effect of molar concentrations

    SciTech Connect (OSTI)

    Mene, Ravindra U. [PDEA's, Annasaheb Waghire College of Science, Arts and Commerce, Otur 412409, M.S. (India); School of Physical Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606, M.S. (India); Mahabole, Megha P. [School of Physical Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606, M.S. (India); Mohite, K.C. [Haribhai. V. Desai College, Pune 411002, M.S. (India); Khairnar, Rajendra S., E-mail: rskhairnarsps@gmail.com [School of Physical Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606, M.S. (India)

    2014-02-01

    Highlights: • We report improved gas sensing and dielectric characteristics of Fe ion exchanged HAp films. • Fe doped HAp film shows maximum gas response at relatively lower temperature. • Response and gas uptake capacity of sensors is improved for appropriate amount of Fe ions in HAp matrix. • Fe-HAp films exhibit remarkable improvement in dielectric properties compared to pure HAp. • Fe doped HAp films show significant improvement in gas sensing as well as in dielectric properties. - Abstract: In the present work Fe doped hydroxyapatite (Fe-HAp) thick films has been successfully utilized to improve the gas sensing as well as its dielectric properties. Initially, HAp nano powder is synthesized by chemical precipitation process and later on Fe ions are doped in HAp by ion exchange process. Structural and morphological modifications are observed by means of X-ray diffraction and scanning electron microscopy analysis. The sensing parameters such as operating temperature, response/recovery time and gas uptake capacity are experimentally determined. The Fe-HAp (0.05 M) film shows improved CO and CO{sub 2} gas sensing capacity at lower operating temperature compared to pure HAp. Moreover, variation of dielectric constant and dielectric loss for pure and Fe-HAp thick films are studied as a function of frequency in the range of 10 Hz–1 MHz. The study reveals that Fe doped HAp thick films improve the sensing and dielectric characteristics as compared to pure HAp.

  7. The existence of warm and optically thick dissipative coronae above accretion disks

    E-Print Network [OSTI]

    Rozanska, A; Belmont, R; Czerny, B; Petrucci, P -O

    2015-01-01

    In the past years, several observations of AGN and X-ray binaries have suggested the existence of a warm T around 0.5-1 keV and optically thick, \\tau ~ 10-20, corona covering the inner parts of the accretion disk. These properties are directly derived from spectral fitting in UV to soft-X-rays using Comptonization models. However, whether such a medium can be both in radiative and hydrostatic equilibrium with an accretion disk is still uncertain. We investigate the properties of such warm, optically thick coronae and put constraints on their existence. We solve the radiative transfer equation for grey atmosphere analytically in a pure scattering medium, including local dissipation as an additional heating term in the warm corona. The temperature profile of the warm corona is calculated assuming it is cooled by Compton scattering, with the underlying dissipative disk providing photons to the corona. Our analytic calculations show that a dissipative thick, (\\tau_{cor} ~ 10-12) corona on the top of a standard ac...

  8. Thickness effect on the structural and electrical properties of poly-SiGe films

    SciTech Connect (OSTI)

    Asafa, T.B., E-mail: asafa@kfupm.edu.sa [KACST-Intel Consortium Center of Excellence in Nano-manufacturing Applications, Riyadh (Saudi Arabia); imec, Kapeldreef 75, 3001 Leuven (Belgium); King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Witvrouw, A. [imec, Kapeldreef 75, 3001 Leuven (Belgium); Schneider, D. [Fraunhofer-Institute for Material and Beam Technology, Winterbergstrasse 28, Dresden (Germany); Moussa, A. [imec, Kapeldreef 75, 3001 Leuven (Belgium); Tabet, N.; Said, S.A.M. [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia)

    2014-01-01

    Graphical abstract: - Highlights: • Stress and Young's modulus of poly-SiGe film are linked to the grain columnar structure. • The above properties remain unchanged for poly-SiGe films thicker than 40 nm. • The point of transition is close to the electron mean free path for SiGe. • Both the resistivity and Hall mobility follow a similar trend. - Abstract: As lateral dimensions of electromechanical devices are scaled down to length scales comparable to electron mean free paths, the influence of thickness effect on their properties becomes sine qua non. This paper presents a detailed study of thickness effect on the Young's modulus, residual stress, resistivity and Hall mobility of ultrathin poly-Si{sub 11}Ge{sub 89} films deposited by low pressure chemical vapour deposition. The Young's moduli for the films thicker than ?40 nm are close to the bulk value (135 GPa) while those of the thinner films are much lower. The reduction in resistivity and subsequent improved Hall mobility as thickness increases are discussed in light of surface morphology which is evident from atomic microscopy images. The near constant values of Young's modulus, resistivity and Hall mobility for the films thicker than ?40 nm are attributed to the columnar grain structure as confirmed by the transmission electron microscopy images.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Controlling rough paths

    E-Print Network [OSTI]

    2013-03-05

    and observe that all the terms are in OCd. 2?I; V. #2. ? so that QAZ d. 2?I; V. #2. ? is in the domain of L; then. jjLQjjd;I p. 1. 2d ? 2. ½jjRZjjZ;I jjWjjg;I jjZ0jjN;I jjXjjg;I ...

  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. 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. (Anthony B.); Rohde, C. A. (Charles 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.

  17. 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.

  18. Harmonic QPOs and Thick Accretion Disk Oscillations in BL Lac Object AO 0235+164

    E-Print Network [OSTI]

    F. K. Liu; G. Zhao; Xue-Bing Wu

    2006-06-27

    Periodic outbursts are observed in many AGNs and usually explained with a supermassive black hole binary (SMBHB) scenario. However, multiple periods are observed in some AGNs and cannot be explained with it. Here we analyze the periodicity of the radio light curves of AO 0235+164 at multi-frequencies and report the discovery of six QPOs in integer ratio 1:2:3:4:5:6 of QPO frequencies, of which the second with period $P_2 = (5.46 \\pm 0.47) {\\rm yr}$ is the strongest. We fit the radio light curves and show that the initial phases of six QPOs have zero or $\\pi$ differences relative to each other. We suggest a harmonic relationship of QPOs. The centroid frequency, relative strength, harmonic relationship and relative initial phases of QPOs are independent of radio frequency. The harmonic QPOs are likely due to the quasi-periodic injection of plasma from an oscillating accretion disk into the jet. We estimate the supermassive black hole mass $M_{\\rm BH} \\simeq (4.72\\pm 2.04) \\times 10^8 M_\\odot$ and the accretion rate $\\dot{m}\\simeq 0.007$. With the knowledge of accretion disk, it implies that the inner region of accretion disk of AO 0235+164 is a radiatively inefficient accretion flow. The oscillation accretion is due to the p-mode oscillation of the thick disk probably excited by a SMBHB. The theoretical predications of fundamental oscillation frequency and the harmonics are well consistent with the observations. Harmonic QPOs would be absent when the thick disk becomes geometrically thin due to the increase of accretion rate. We discuss the observations of AO 0235+164 basing on the SMBHB-thick disk oscillation scenario.

  19. Testing and analysis to determine the shell thickness required to prevent puncture

    SciTech Connect (OSTI)

    Ammerman, D.J.; Radloff, H.D.; Eifert, E.J.

    1998-05-01

    Type B radioactive material packages are required to withstand a hypothetical puncture accident of a free fall from a height of one meter onto a 15 cm diameter mild steel puncture probe. For many packages it is desirable to have this accident event not result in puncture or tearing of the outer shell of the package. The wall thickness necessary to prevent this has historically been determined by test or the use of empirical relations. This technique generally results in overly conservative designs, but the degree of conservatism is uncertain. The use of modem finite element codes to determine package response to puncture accidents can result in designs that are both safe and economical. The work reported in this paper is aimed at developing a method to analytically determine the wall thickness required to prevent puncture. For designers and regulators to have confidence in this analytical method, however, it must be benchmarked against test results. A series of tests has been conducted with differing shell thicknesses, shell materials of mild steel and stainless steel, and shell backing materials of lead, foam, and air. The results of these tests have been compared with pre-test analytical predictions of the response obtained from the nonlinear transient dynamic finite element program PRONTO-2D. From this comparison it can be seen that the finite element method can accurately predict the response of packages to puncture accidents. This implies that an analytical technique based on the finite element method can be used to design packages having known response and margin of safety against tearing of the outer shell. In addition, the analytical technique can accurately predict the deformed shape of the package following the test. This may be important for subsequent calculations, such as external dose and heat input during a thermal event.

  20. Critical Thickness for Itinerant Ferromagnetism in Ultrathin Films of SrRuO_3

    SciTech Connect (OSTI)

    Xia, Jing

    2010-04-05

    Ultrathin films of the itinerant ferromagnet SrRuO{sub 3} were studied using transport and magneto-optic polar Kerr effect. We find that below 4 monolayers the films become insulating and their magnetic character changes as they loose their simple ferromagnetic behavior. We observe a strong reduction in the magnetic moment which for 3 monolayers and below lies in the plane of the film. Exchange-bias behavior is observed below the critical thickness, and may point to induced antiferromagnetism in contact with ferromagnetic regions.

  1. Thick target measurement of the 40Ca(alpha,gamma)44Ti reaction rate

    SciTech Connect (OSTI)

    Sheets, S A; Burke, J T; Scielzo, N D; Phair, L; Bleuel, D; Norman, E B; Grant, P G; Hurst, A M; Tumey, S; Brown, T A; Stoyer, M

    2009-02-06

    The thick-target yield for the {sup 40}Ca({alpha},{gamma}){sup 44}Ti reaction has been measured for E{sub beam} = 4.13, 4.54, and 5.36 MeV using both an activation measurement and online {gamma}-ray spectroscopy. The results of the two measurements agree. From the measured yield a reaction rate is deduced that is smaller than statistical model calculations. This implies a smaller {sup 44}Ti production in supernova compared to recently measured {sup 40}Ca({alpha},{gamma}){sup 44}Ti reaction rates.

  2. Independent measurement of femoral cortical thickness and cortical bone density using clinical CT

    E-Print Network [OSTI]

    Treece, G. M.; Gee, A. H.

    2014-12-05

    for CBM v2 in eq. (4) by using eq. (1) to simulate the CT data variation c(x) through ideal cortices, i.e. with perfectly constant density and no pores, surrounded by material which is also at a constant (but lower) density. These cortices were blurred... are shown in Fig. 4. 3.2. Comparing HRpQCT and QCT data Moving on from simulations, we examined data from a study ethically approved by the Medical University of 5 0 1 2 3 4 5 0 500 1000 1500 thickness (mm) de ns ity (H U) yb y m raw data model fit...

  3. The Compton-thick AGN in the GPS radio source OQ+208

    E-Print Network [OSTI]

    M. Guainazzi; C. Stanghellini; P. Grandi

    2002-08-30

    We report in this paper the ASCA discovery of the first radio-loud Active Galactic Nucleus (AGN) covered by a Compton-thick X-ray absorber, in the GigaHertz Peaked Spectrum (GPS) radio source OQ+208. It represents one of the few available direct measurements of dense matter in the nuclear environment of this class of sources, which may provide the confining medium to the radio-emitting region if GPS sources are indeed "frustrated" classical radio doubles. The perspective of future studies with XEUS are discussed.

  4. 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.

  5. 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.

  6. Pure geometric thick $f(R)$-branes: stability and localization of gravity

    E-Print Network [OSTI]

    Zhong, Yuan

    2015-01-01

    We study two exactly solvable five-dimensional thick brane world models in pure metric $f(R)$ gravity. Working in the Einstein frame, we show that these solutions are stable against small linear perturbations, including the tensor, vector, and scalar modes. For both models, the corresponding gravitational zero mode is localized on the brane, which leads to the four-dimensional Newton's law; while the massive modes are nonlocalized and they only contribute a small correction to the Newton's law at a large distance.

  7. Apparatus and method for measuring the thickness of a semiconductor wafer

    DOE Patents [OSTI]

    Ciszek, T.F.

    1995-03-07

    Apparatus for measuring thicknesses of semiconductor wafers is discussed, comprising: housing means for supporting a wafer in a light-tight environment; a light source mounted to the housing at one side of the wafer to emit light of a predetermined wavelength to normally impinge the wafer; a light detector supported at a predetermined distance from a side of the wafer opposite the side on which a light source impinges and adapted to receive light transmitted through the wafer; and means for measuring the transmitted light. 4 figs.

  8. Cooperative emission of a pulse train in an optically thick scattering medium

    E-Print Network [OSTI]

    Kwong, C C; Delande, D; Pierrat, R; Wilkowski, D

    2015-01-01

    An optically thick cold atomic cloud emits a coherent flash of light in the forward direction when the phase of an incident probe field is abruptly changed. Due to cooperativity, the duration of this phenomena can be much shorter than the excited lifetime of a single atom and, surprisingly, it weakly depends on the temperature of the gas and on the probe frequency. Repeating periodically the abrupt change of the incident field phase, we generate a forward transmitted train of pulses with short repetition time. It is even possible to quench single atom fluorescence, transferring almost completely the incident power into the pulse train with a high intensity contrast.

  9. Effective Diffusion-Medium Thickness for Simplified Polymer-Electrolyte-Fuel-Cell Modeling

    SciTech Connect (OSTI)

    Weber, Adam; Weber, Adam Z.

    2008-07-30

    In this manuscript, conformal mapping is applied to a rib/channel domain of a polymer-electrolyte-fuel-cell diffusion medium. The analysis leads to the calculation of an effective diffusion-medium thickness, which can subsequently be used in 1-D simulations to account for the average rib/channel 2-D geometric effect. Extensions of the analysis to anisotropic and multilayer diffusion media are also given. Both equations and figures show the impact on a given variable at the catalyst layer of having a combined conducting/nonconducting boundary across from it.

  10. 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.

  11. 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.

  12. 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].

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

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and Pion decaysArticle) | SciTech ConnectPatent: Thick-shell

  14. Effects of ultrasound and sodium lauryl sulfate on the transdermal delivery of hydrophilic permeants: Comparative in vitro studies with full-thickness and split-thickness pig and human skin

    E-Print Network [OSTI]

    Seto, Jennifer E.

    The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness ...

  15. Modelling solar low-lying cool loops with optically thick radiative losses

    E-Print Network [OSTI]

    Sasso, C; Spadaro, D

    2015-01-01

    We investigate the increase of the DEM (differential emission measure) towards the chromosphere due to small and cool magnetic loops (height $\\lesssim8$~Mm, $T\\lesssim10^5$~K). In a previous paper we analysed the conditions of existence and stability of these loops through hydrodynamic simulations, focusing on their dependence on the details of the optically thin radiative loss function used. In this paper, we extend those hydrodynamic simulations to verify if this class of loops exists and it is stable when using an optically thick radiative loss function. We study two cases: constant background heating and a heating depending on the density. The contribution to the transition region EUV output of these loops is also calculated and presented. We find that stable, quasi-static cool loops can be obtained by using an optically thick radiative loss function and a background heating depending on the density. The DEMs of these loops, however, fail to reproduce the observed DEM for temperatures between $4.6<\\log...

  16. Vacuum densities for a thick brane in AdS spacetime

    E-Print Network [OSTI]

    A. A. Saharian; A. L. Mkhitaryan

    2007-10-18

    For a massive scalar field with general curvature coupling parameter we evaluate Wightman function, vacuum expectation values of the field square and the energy-momentum tensor induced by a $Z_{2}$-symmetric brane with finite thickness located on $(D+1)$-dimensional AdS bulk. For the general case of static plane symmetric interior structure the expectation values in the region outside the brane are presented as the sum of free AdS and brane induced parts. For a conformally coupled massless scalar the brane induced part in the vacuum energy-momentum tensor vanishes. In the limit of strong gravitational fields the brane induced parts are exponentially suppressed for points not too close to the brane boundary. As an application of general results a special model is considered in which the geometry inside the brane is a slice of the Minkowski spacetime orbifolded along the direction perpendicular to the brane. For this model the Wightman function, vacuum expectation values of the field square and the energy-momentum tensor inside the brane are evaluated. It is shown that for both minimally and conformally coupled scalar fields the interior vacuum forces acting on the brane boundaries tend to decrease the brane thickness.

  17. Constraints on neutron skin thickness in 208Pb and density-dependent symmetry energy

    E-Print Network [OSTI]

    Jianmin Dong; Wei Zuo; Jianzhong Gu

    2015-04-09

    Accurate knowledge about the neutron skin thickness $\\Delta R_{np}$ in $^{208}$Pb has far-reaching implications for different communities of nuclear physics and astrophysics. Yet, the novel Lead Radius Experiment (PREX) did not yield stringent constraint on the $\\Delta R_{np}$ recently. We employ a more practicable strategy currently to probe the neutron skin thickness of $^{208}$Pb based on a high linear correlation between the $\\Delta R_{np}$ and $J-a_{\\text{sym}}$, where $J$ and $a_{\\text{sym}}$ are the symmetry energy (coefficient) of nuclear matter at saturation density and of $^{208}$Pb. An accurate $J-a_{\\text{sym}}$ thus places a strong constraint on the $\\Delta R_{np}$. Compared with the parity-violating asymmetry $A_{\\text{PV}}$ in the PREX, the reliably experimental information on the $J-a_{\\text{sym}}$ is much more easily available attributed to a wealth of measured data on nuclear masses and on decay energies. The density dependence of the symmetry energy is also well constrained with the $J-a_{\\text{sym}}$. Finally, with a `tomoscan' method, we find that one just needs to measure the nucleon densities in $^{208}$Pb starting from $R_{m} = 7.61\\pm0.04$ fm to obtain the $\\Delta R_{np}$ in hadron scattering experiments, regardless of its interior profile that is hampered by the strong absorption.

  18. Constraints on neutron skin thickness in 208Pb and density-dependent symmetry energy

    E-Print Network [OSTI]

    Dong, Jianmin; Gu, Jianzhong

    2015-01-01

    Accurate knowledge about the neutron skin thickness $\\Delta R_{np}$ in $^{208}$Pb has far-reaching implications for different communities of nuclear physics and astrophysics. Yet, the novel Lead Radius Experiment (PREX) did not yield stringent constraint on the $\\Delta R_{np}$ recently. We employ a more practicable strategy currently to probe the neutron skin thickness of $^{208}$Pb based on a high linear correlation between the $\\Delta R_{np}$ and $J-a_{\\text{sym}}$, where $J$ and $a_{\\text{sym}}$ are the symmetry energy (coefficient) of nuclear matter at saturation density and of $^{208}$Pb. An accurate $J-a_{\\text{sym}}$ thus places a strong constraint on the $\\Delta R_{np}$. Compared with the parity-violating asymmetry $A_{\\text{PV}}$ in the PREX, the reliably experimental information on the $J-a_{\\text{sym}}$ is much more easily available attributed to a wealth of measured data on nuclear masses and on decay energies. The density dependence of the symmetry energy is also well constrained with the $J-a_{\\...

  19. 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, ?F {sub ?} = 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.

  20. Acceleration of wind in optically thin and thick black hole accretion disks simulated in general relativity

    E-Print Network [OSTI]

    Moller, Anton

    2015-01-01

    We study the force balance and resulting acceleration of gas in general relativity basing on simulations of accretion on a stellar-mass, non-rotating black hole. We compare properties of acceleration in an optically thin, radiatively inefficient disk, and in an optically thick, super-critical disk accreting at 10 times the Eddington rate. We study both the average forces acting at given location and forces acting on a gas along its individual trajectory. We show that the acceleration is not a continuous process -- in most gases gas is accelerated only in short-lasting episodes. We find that in the case of optically thin disks gas is pushed out by magnetic field in the polar region and by thermal pressure and centrifugal force below the disk surface. In case of optically thick, radiative accretion, it is the radiation pressure which accelerates the gas in the polar funnel and which compensates and sometimes prevails, together with the centrifugal force, the gravity deeper in the disk. We also show that the New...

  1. 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. [Department of Physics, Nagoya University, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Onishi, T., E-mail: fukui@a.phys.nagoya-u.ac.jp [Department of Astrophysics, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Nakaku, Sakai, Osaka 599-8531 (Japan)

    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 ? 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 ? 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.

  2. Propagation of ionizing radiation in HII regions: the effects of optically thick density fluctuations

    E-Print Network [OSTI]

    C. Giammanco; J. E. Beckman; A. Zurita; M. Relaño

    2004-05-24

    The accepted explanation of the observed dichotomy of two orders of magnitude between in situ measurements of electron density in HII regions, derived from emission line ratios, and average measurements based on integrated emission measure, is the inhomogeneity of the ionized medium. This is expressed as a "filling factor", the volume ratio of dense to tenuous gas, measured with values of order 10^-3. Implicit in the filling factor model as normally used, is the assumption that the clumps of dense gas are optically thin to ionizing radiation. Here we explore implications of assuming the contrary: that the clumps are optically thick. A first consequence is the presence within HII regions of a major fraction of neutral hydrogen. We estimate the mean H^o/H^+ ratio for a population of HII regions in the spiral galaxy NGC 1530 to be the order of 10, and support this inference using dynamical arguments. The optically thick clumpy models allow a significant fraction of the photons generated by the ionizing stars to escape from their HII region. We show, by comparing model predictions with observations, that these models give an account at least as good as, and probably better than that of conventional models, of the radial surface brightness distribution and of selected spectral line diagnostics for physical conditions within HII regions. These models explain how an HII region can appear, from its line ratios, to be ionization bounded, yet permit a major fraction of its ionizing photons to escape.

  3. Comparisons on thin and thick neutron target for low energy proton beam

    SciTech Connect (OSTI)

    Zhong, B.; Yu, G.; Wang, X.; Wang, K. [Dept. of Engineering Physics, Tsinghua Univ., Beijing 100084 (China)

    2012-07-01

    As the progress on accelerator physics and neutronics, the compact neutron sources driven by low energy and high intensity beam are becoming extensively developed and researched all around the world. The neutron target of an accelerator driven neutron source is one of the key components, and the stability of the neutron target affect the operation and performance of the neutron facility. When a low energy proton is projected to the beryllium target, the main reaction is the inelastic scattering between the proton and extra-nuclear electrons. As the decreasing of proton energy, the rate of elastic scattering between proton and target nucleus begins to increase. When the energy of proton is very low, the pickup charge reaction begins to appear. Focus on the problems brought by high intensity proton beam such as proton implantation, radiation damages, heat deposition and gas production, we performed sufficient numerical simulations for both thin and thick target determined by proton range. The results show that the critical problem for thick target is the proton implantation, causing the forming of bubbles and beryllium flaked in vacuum. The thin target sacrifices a little neutron yield, but avoid the proton stopped in target, and decrease the radiation damage and energy deposition. (authors)

  4. Cavity-Integrated Ultra-Narrow Superconducting Nanowire Single-Photon Detector Based on a Thick Niobium Nitride Film

    E-Print Network [OSTI]

    Marsili, Francesco

    We propose a design for cavity-integrated Superconducting Nanowire Single-Photon Detectors based on 20-nm-wide 10-nm-thick nanowires. Our simulations show that these detectors can potentially reach ~90% device detection ...

  5. The Effect of Braze Interlayer Thickness on the Mechanical Strength of Alumina Brazed with Ag-CuO Braze Alloys

    SciTech Connect (OSTI)

    Erskine, Kevin M.; Meier, Alan; Joshi, Vineet V.; Pilgrim, Steven M.

    2014-12-01

    The effect of braze interlayer thickness on the strength of alumina brazed with silver-copper oxide reactive air braze (RAB) alloys was evaluated using a four point bend test configuration. The brazed samples had an average fracture strength of 180 MPa or approximately 60 percent of the average monolithic alumina strength. The joint strength values obtained exceeded the yield strength and ultimate tensile strength of the silver interlayer indicating strong ceramic to metal adhesion and the development of a triaxial stress state in the braze interlayer. The average fracture strength was relatively constant (190 ± 60 MPa) in the thickness range of 0.030 mm to 0.230 mm for all test conditions. The braze fracture strength then decreased down to 100 ± 30 MPa as the braze thickness increased from 0.230 mm to 0.430 mm indicating a loss of triaxial constraint with increasing interlayer thickness. In addition, four different fracture modes were observed.

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

    Office of Energy Efficiency and Renewable Energy (EERE)

    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,...

  7. Thickness Dependence of Oxygen Reduction Reaction Kinetics on Strontium-Substituted Lanthanum Manganese Perovskite Thin-Film Microelectrodes

    E-Print Network [OSTI]

    la O’, G. J.

    Oxygen reduction reaction (ORR) kinetics was investigated on dense La?.?Sr?.?MnO? microelectrodes as a function of temperature and microelectrode thickness using electrochemical impedance spectroscopy. The surface oxygen ...

  8. A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory 

    E-Print Network [OSTI]

    Lo, Tzu-Wei

    2005-11-01

    -Acousto Photonic Non-Destructive Evaluation (TAP-NDE) is employed to remotely initiate and acquire interrogating ultrasonic waves. Parameters including pressure, temperature and plate thickness are determined through exploring the dispersion features...

  9. Multilayer graphene stacks grown by different methods-thickness measurements by X-ray diffraction, Raman spectroscopy and optical transmission

    SciTech Connect (OSTI)

    Tokarczyk, M., E-mail: mateusz.tokarczyk@fuw.edu.pl; Kowalski, G.; K?pa, H.; Grodecki, K.; Drabi?ska, A. [University of Warsaw, Institute of Experimental Physics, Faculty of Physics (Poland); Strupi?ski, W. [Institute of Electronic Materials Technology (Poland)

    2013-12-15

    X-ray diffraction, Raman spectroscopy and Optical absorption estimates of the thickness of graphene multi layer stacks (number of graphene layers) are presented for three different growth techniques. The objective of this work was focused on comparison and reconciliation of the two already widely used methods for thickness estimates (Raman and Absorption) with the calibration of the X-ray method as far as Scherer constant K is concerned and X-ray based Wagner-Aqua extrapolation method.

  10. Thickness effects on fracture toughness of ultra-high-molecular- weight polyethylene via the J-integral 

    E-Print Network [OSTI]

    Lehmann, Jarvis Craig

    1992-01-01

    in existence. Very little has been reported in the literature concerning fracture of UHMW-PE. This paper reports a study of thickness effects on mode I fracture toughness of a compression molded UHMW-PE plate material via the J-integral. Six sets... . . . 9 5 . . . . 1 2 2 . . . . 1 5 7 V DISCUSSION OF RESULTS. . . . . 1 8 1 UHMW-PE AS RECEIVED MATERIAL. MOLECULAR WEIGHT. DENSITY TENSILE PROPERTIES . . Rate Effects Plate Thru Thickness Effects. . FRACTURE TOUGHNESS . . . . . Plate Thru...

  11. 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.

  12. 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 [Universit_e de Toulouse, Toulouse, France (Europe); National Institute of Standards Technology, Gaithersburg, MD (United States); Xin, Huolin L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhu, Ye [Monash Univ., Melbourne, VIC (Australia); Dwyer, Christian [Peter Grunberg Institute, Julich, Germany (Europe)

    2014-12-01

    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. Implications for the interpretation of atomic-scale elemental maps are discussed.

  13. Embedding Inkjet-printed Antennas into Plywood Structures for Identification and Sensing

    E-Print Network [OSTI]

    Tentzeris, Manos

    University of Technology Tampere, Finland M. Tentzeris School of Electrical and Computer Engineering Georgia, J. Virtanen, L. Sydänheimo, L. Ukkonen Rauma Research Unit, Department of Electronics Tampere

  14. 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.

  15. 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.

  16. Lightweight plywood construction assembly : a lightweight approach to the elegant utilitarian form

    E-Print Network [OSTI]

    Kwong, Edmund Ming Yip

    2009-01-01

    What will be the fundamental aspect and concern of today's good design? As global energy reserves deplete over the coming decades, a strategy of reduced consumption will be essential to the production of furniture and ...

  17. 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.

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

    DOE Patents [OSTI]

    Hollis, Kendall (Los Alamos, NM); Bartram, Brian (Los Alamos, NM)

    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.

  19. 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.

  20. Thick-film technology for ultra high vacuum interfaces of micro-structured traps

    E-Print Network [OSTI]

    Delia Kaufmann; Thomas Collath; M. Tanveer Baig; Peter Kaufmann; Eman Asenwar; Michael Johanning; Christof Wunderlich

    2012-01-26

    We adopt thick-film technology to produce ultra high vacuum compatible interfaces for electrical signals. These interfaces permit voltages of hundreds of Volts and currents of several Amperes and allow for very compact vacuum setups, useful in quantum optics in general, and especially for quantum information and quantum simulations using miniaturized traps for ions or neutral atoms. Such printed circuits can also be useful as pure in-vacuum devices. We demonstrate a specific interface, which provides eleven current feedthroughs, more than 70 dc feedthroughs and a feedthrough for radio frequencies. We achieve a pressure in the low 1e-11mbar range and demonstrate the full functionality of the interface by trapping chains of cold ytterbium ions, which requires all of the signals mentioned above being present. In addition, a versatile multi-channel device for supplying precise time-dependent voltages has been developed.

  1. 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.

  2. 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.

  3. The Association of Jet Production with Geometrically Thick Accretion Flows and Black Hole Rotation

    E-Print Network [OSTI]

    David L. Meier

    2000-10-12

    A model is presented in which the strongest radio-emitting jet outflows are produced in black hole systems when the accretion is a geometrically thick ($H/R \\sim 1$) inflow ({\\it e.g.}, ADAF, CDAF) {\\em and} if the black hole is rotating. For galactic black hole candidates, the model naturally accounts for the observed correlation of jet outflow with the black hole hard emission state and predicts an association of strong jets with rapid black hole rotation. When extended to the supermassive case, the model accounts for the highest radio galaxy and quasar jet powers and provides additional theoretical support for the ``spin paradigm'', which asserts that radio loud quasars are produced by Kerr holes and radio quiet ones by Schwarzschild holes. In some cases, the angular momentum and energy outflow in the jet may be large enough to significantly alter the structure of the accretion flow from that predicted by current models.

  4. Test of Thick Pixelated Orbotech Detectors with and without Steering Grids

    E-Print Network [OSTI]

    I. Jung; A. Garson III; H. Krawczynski; A. Burger; M. Groza; J. Matteson; R. T. Skelton

    2006-08-30

    We report here on the optimization of 0.5 cm thick pixelated Orbotech CZT detectors with regards to the best contacting materials and the use of steering grids. We evaluated the performance of different contacting materials. Our study differs from earlier ones in that we investigated the performance of different anode and cathode materials separately. We obtain the best performance with Au cathodes. For different anode materials Ti and In give the best energy resolutions. The detector (2.0 x 2.0 x 0.5 cm, 8 x 8 pixels) shows excellent 59 keV, 122 keV and 662 keV energy resolutions of 1.4 keV, 1.9 keV, and 7.4 keV, respectively. Furthermore, we report on using steering grids to improve on the performance of the pixelated detectors. Previously, the benefit of steering grids had been limited by additional electronic noise associated with currents between the negatively biased steering grids and the anode pixels. We are currently exploring the possibility to isolate the steering grid from the CZT substrates by a thin layer of Al$_2$O$_3$. We performed a series of measurements to determine by how much the isolation layer reduces the grid-pixel currents. Comparing the currents between two Au contacts before and after isolating one of the two contacts from the CZT with a 700 nm thick layer of Al2O3, we measure that the isolation layer reduces the currents by a factor of about 10 at 500 V. We present some results from a detector before and after deposition of an isolated steering grid. The grid indeed improves on the detectors energy resolution and detection efficiency. We show that simulations can be used to model the anode to cathode charge correlation in excellent agreement with the experimental results.

  5. THE ANGULAR DISTRIBUTION OF Ly{alpha} RESONANT PHOTONS EMERGING FROM AN OPTICALLY THICK MEDIUM

    SciTech Connect (OSTI)

    Yang Yang; Shu Chiwang [Division of Applied Mathematics, Brown University, Providence, RI 02912 (United States); Roy, Ishani [Imaging Sciences and Biomedical Engineering Division, St Thomas Hospital, Kings College London, SE1 7EH (United Kingdom); Fang Lizhi [Department of Physics, University of Arizona, Tucson, AZ 85721 (United States)

    2013-07-20

    We investigate the angular distribution of Ly{alpha} photons scattering or emerging from an optically thick medium. Since the evolution of specific intensity I in frequency space and angular space are coupled with each other, we first develop the WENO numerical solver to find the time-dependent solutions of the integro-differential equation of I in frequency and angular space simultaneously. We first show that the solutions with the Eddington approximation, which assume that I is linearly dependent on the angular variable {mu}, yield similar frequency profiles of the photon flux as those without the Eddington approximation. However, the solutions of the {mu} distribution evolution are significantly different from those given by the Eddington approximation. First, the angular distribution of I is found to be substantially dependent on the frequency of the photons. For photons with the resonant frequency {nu}{sub 0}, I contains only a linear term of {mu}. For photons with frequencies at the double peaks of the flux, the {mu}-distribution is highly anisotropic; most photons are emitted radially forward. Moreover, either at {nu}{sub 0} or at the double peaks, the {mu} distributions actually are independent of the initial {mu} distribution of photons of the source. This is because the photons with frequencies either at {nu}{sub 0} or the double peaks undergo the process of forgetting their initial conditions due to resonant scattering. We also show that the optically thick medium is a collimator of photons at the double peaks. Photons from the double peaks form a forward beam with a very small opening angle.

  6. Performance characterization of a MVCT scanner using multislice thick, segmented cadmium tungstate-photodiode detectors

    SciTech Connect (OSTI)

    Kirvan, P. F.; Monajemi, T. T.; Fallone, B. G.; Rathee, S. [Department of Physics, University of Alberta, Edmonton, Alberta T6E 2E1 (Canada); Department of Medical Physics, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Physics, University of Alberta, Edmonton, Alberta T6E 2E1 (Canada); Department of Medical Physics, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

    2010-01-15

    Purpose: Megavoltage computed tomography (MVCT) and megavoltage cone beam computed tomography (MVCBCT) can be used for visualizing anatomical structures prior to radiation therapy treatments to assist in patient setup and target localization. These systems are less susceptible to metal artifacts and provide better CT number linearity than conventional CT scanners. However, their contrast is limited by the properties of the megavoltage photons and the low detective quantum efficiency (DQE) of flat panel detector systems currently available. By using higher DQE, thick, segmented cadmium tungstate detectors, the authors can improve the low contrast detectability of a MVCT system. This in turn would permit greater soft tissue visualization for a given radiation dose, allowing MVCT to be used in more clinical situations. Methods: This article describes the evaluation of our prototype system that uses thick, segmented detectors. In order to create images using a dose that would be acceptable for day to day patient imaging, the authors evaluated their system using the low intensity bremsstrahlung component of a 6 MeV electron beam. The system was evaluated for its uniformity, high contrast resolution, low contrast detectability, signal to noise ratio, contrast to noise ratio, and CT number linearity. Results: The prototype system was found to have a high contrast spatial resolution of about 5 line pairs per cm, and to be able to visualize a 15 mm 1.5% contrast target with 2 cGy of radiation dose delivered. SNR{sup 2} vs radiation dose and mean pixel value vs electron density curves were linear. Conclusions: This prototype system shows a large improvement in low contrast detectability over current MVCBCT systems.

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

    DOE Patents [OSTI]

    Mowrey, Gary L. (Jefferson Boro, PA); Ganoe, Carl W. (Pittsburgh, PA); Monaghan, William D. (Dravosburg, PA)

    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.

  8. Thick-to-Thin Filament Surface Distance Modulates Cross-Bridge Kinetics in Drosophila Flight Muscle

    SciTech Connect (OSTI)

    Tanner, Bertrand C.W.; Farman, Gerrie P.; Irving, Thomas C.; Maughan, David W.; Palmer, Bradley M.; Miller, Mark S. (IIT); (Vermont); (BU)

    2012-09-19

    The demembranated (skinned) muscle fiber preparation is widely used to investigate muscle contraction because the intracellular ionic conditions can be precisely controlled. However, plasma membrane removal results in a loss of osmotic regulation, causing abnormal hydration of the myofilament lattice and its proteins. We investigated the structural and functional consequences of varied myofilament lattice spacing and protein hydration on cross-bridge rates of force development and detachment in Drosophila melanogaster indirect flight muscle, using x-ray diffraction to compare the lattice spacing of dissected, osmotically compressed skinned fibers to native muscle fibers in living flies. Osmolytes of different sizes and exclusion properties (Dextran T-500 and T-10) were used to differentially alter lattice spacing and protein hydration. At in vivo lattice spacing, cross-bridge attachment time (t{sub on}) increased with higher osmotic pressures, consistent with a reduced cross-bridge detachment rate as myofilament protein hydration decreased. In contrast, in the swollen lattice, t{sub on} decreased with higher osmotic pressures. These divergent responses were reconciled using a structural model that predicts t{sub on} varies inversely with thick-to-thin filament surface distance, suggesting that cross-bridge rates of force development and detachment are modulated more by myofilament lattice geometry than protein hydration. Generalizing these findings, our results suggest that cross-bridge cycling rates slow as thick-to-thin filament surface distance decreases with sarcomere lengthening, and likewise, cross-bridge cycling rates increase during sarcomere shortening. Together, these structural changes may provide a mechanism for altering cross-bridge performance throughout a contraction-relaxation cycle.

  9. 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.

  10. 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 0.5? (? 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

  11. 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}.

  12. 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.

  13. Investigation of the effect of water content, thickness and optical properties on laser ablation of biological tissue 

    E-Print Network [OSTI]

    Vaidyanathan, Varadarajan

    1991-01-01

    studied as p. m/pulse showed an exponential decrease with increasing thickness as did the mass removed/pulse. The front diameter showed an increase with increasing thickness. The effect of increasing repetition rate on the energy output of the Er...:YAG laser was studied. The energy/pulse due to single pulse as well as multiple pulses was monitored. The energy/ pulse showed an increase with increasing repetition rate for both cases with a tendency to saturate. The effect of beamwidth on ablation rate...

  14. An iterative procedure to obtain inverse response functions for thick-target correction of measured charged-particle spectra

    E-Print Network [OSTI]

    S. Pomp; U. Tippawan

    2006-08-25

    A new method for correcting charged-particle spectra for thick target effects is described. Starting with a trial function, inverse response functions are found by an iterative procedure. The variances corresponding to the measured spectrum are treated similiarly and in parallel. Oscillations of the solution are avoided by rebinning the data to finer bins during a correction iteration and back to the original or wider binning after each iteration. This thick-target correction method has been used for data obtained with the MEDLEY facility at the The Svedberg Laboratory, Uppsala, Sweden, and is here presented in detail and demonstrated for two test cases.

  15. 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).

  16. 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.

  17. X-ray fluorescent lines from the Compton-thick AGN in M5

    E-Print Network [OSTI]

    Xu, Weiwei; Gou, Lijun; Liu, Jiren

    2015-01-01

    The cold disk/torus gas surrounding AGN emits fluorescent lines when irradiated by hard X-ray photons. The fluorescent lines of elements other than Fe and Ni are rarely detected due to their relative faintness. We report the detection of K$\\alpha$ lines of neutral Si, S, Ar, Ca, Cr, and Mn, along with the prominent Fe K$\\alpha$, Fe K$\\beta$, and Ni K$\\alpha$ lines, from the deep Chandra observation of the low-luminosity Compton-thick AGN in M51. The Si K$\\alpha$ line at 1.74 keV is detected at $\\sim3\\sigma$, the other fluorescent lines have a significance between 2 and 2.5 $\\sigma$, while the Cr line has a significance of $\\sim1.5\\sigma$. These faint fluorescent lines are made observable due to the heavy obscuration of the intrinsic spectrum of M51, which is revealed by Nustar observation above 10 keV. The hard X-ray continuum of M51 from Chandra and Nustar can be fitted with a power-law spectrum with an index of 1.8, reprocessed by a torus with an equatorial column density of $N_{\\rm H}\\sim7\\times10^{24}$ cm...

  18. Unstable mass-outflows in geometrically thick accretion flows around black holes

    E-Print Network [OSTI]

    Okuda, Toru

    2015-01-01

    Accretion flows around black holes generally result in mass-outflows that exhibit irregular behavior quite often. Using 2D time-dependent hydrodynamical calculations, we show that the mass-outflow is unstable in the cases of thick accretion flows such as the low angular momentum accretion flow and the advection-dominated accretion flow. For the low angular momentum flow, the inward accreting matter on the equatorial plane interacts with the outflowing gas along the rotational axis and the centrifugally supported oblique shock is formed at the interface of both the flows, when the viscosity parameter $\\alpha$ is as small as $\\alpha \\le 10^{-3}$. The hot and rarefied blobs, which result in the eruptive mass-outflow, are generated in the inner shocked region and grow up toward the outer boundary. The advection-dominated accretion flow attains finally in the form of a torus disc with the inner edge of the disc at $3R_{\\rm g} \\le r \\le 6R_{\\rm g}$ and the center at $6R_ {\\rm g} \\le r \\le 10R_{\\rm g}$, and a series...

  19. Toward Application of a Thick Gas Electron Multiplier (THGEM) Readout for a Dark Matter Detector

    E-Print Network [OSTI]

    Gai, M; Ni, K; Rubin, D A R; Wongjirad, T; Alon, R; Breskin, Amos; Cortesi, M; Miyamoto, J

    2007-01-01

    The Yale-Weizmann collaboration aims to develop a low-radioactivity (low-background) cryogenic noble liquid detector for Dark-Matter (DM) search in measurements to be performed deep underground as for example carried out by the XENON collaboration. A major issue is the background induced by natural radioactivity of present-detector components including the Photo Multiplier Tubes (PMT) made from glass with large U-Th content. We propose to use advanced Thick Gaseous Electron Multipliers (THGEM) recently developed at the Weizmann Institute of Science (WIS). These "hole-multipliers" will measure in a two-phase (liquid/gas) Xe detector electrons extracted into the gas phase from both ionization in the liquid as well as scintillation-induced photoelectrons from a CsI photocathode immersed in LXe. We report on initial tests (in gas) of THGEM made out of Cirlex (Kapton) which is well known to have low Ra-Th content instead of the usual G10 material with high Ra-Th content.

  20. Test results of a corrosion logging technique using electromagnetic thickness and pipe analysis logging tools

    SciTech Connect (OSTI)

    Iliyan, I.S.; Brown, G.A.; Cotton, W.J. Jr.

    1983-04-01

    Recent innovations in subsurface corrosion practices of the Arabian American Oil Co. (ARAMCO) have reduced logging and workover costs substantially and have permitted the detection of corrosion in the outer string of two concentric casing strings. At the request of ARAMCO, Schlumberger conducted test under both simulated and field conditions. Results showed that the data required to evaluate casing corrosion in a 7-in.X9 5/8-in. completion can be obtained during a single logging run using a 21.6-in. coil spacing electromagnetic thickness tool (ETT-A /SUP TM/ ) sonde (as opposed to two runs with 17.6-in. and 21.6-in. sondes previously used). In addition, corrosion of the outer string of 9 5/8-in. or 13 3/8-in. casing can be detected by using the results of the ETT-A logs and pipe-analysis tool (PAT) logs or caliper logs. To date, the application of this technique has been very successful in ARAMCO's operations.

  1. 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 10 days 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.

  2. Toward Application of a Thick Gas Electron Multiplier (THGEM) Readout for a Dark Matter Detector

    E-Print Network [OSTI]

    M. Gai; D. N. McKinsey; K. Ni; D. A. R. Rubin; T. Wongjirad; R. Alon; A. Breskin; M. Cortesi; J. Miyamoto

    2007-06-08

    The Yale-Weizmann collaboration aims to develop a low-radioactivity (low-background) cryogenic noble liquid detector for Dark-Matter (DM) search in measurements to be performed deep underground as for example carried out by the XENON collaboration. A major issue is the background induced by natural radioactivity of present-detector components including the Photo Multiplier Tubes (PMT) made from glass with large U-Th content. We propose to use advanced Thick Gaseous Electron Multipliers (THGEM) recently developed at the Weizmann Institute of Science (WIS). These "hole-multipliers" will measure in a two-phase (liquid/gas) Xe detector electrons extracted into the gas phase from both ionization in the liquid as well as scintillation-induced photoelectrons from a CsI photocathode immersed in LXe. We report on initial tests (in gas) of THGEM made out of Cirlex (Kapton) which is well known to have low Ra-Th content instead of the usual G10 material with high Ra-Th content.

  3. The Chandra/HETG view of NGC 1365 in a Compton-thick state

    E-Print Network [OSTI]

    Nardini, E; Reeves, J N; Braito, V; Risaliti, G; Costa, M

    2015-01-01

    We present the analysis of a Chandra High-Energy Transmission Grating (HETG) observation of the local Seyfert galaxy NGC 1365. The source, well known for its dramatic X-ray spectral variability, was caught in a reflection-dominated, Compton-thick state. The high spatial resolution afforded by Chandra allowed us to isolate the soft X-ray emission from the active nucleus, neglecting most of the contribution from the kpc-scale starburst ring. The HETG spectra thus revealed a wealth of He- and H-like lines from photoionized gas, whereas in larger aperture observations these are almost exclusively produced through collisional ionization in the circumnuclear environment. Once the residual thermal component is accounted for, the emission-line properties of the photoionized region close to the hard X-ray continuum source indicate that NGC 1365 has some similarities to the local population of obscured active galaxies. In spite of the limited overall data quality, several soft X-ray lines seem to have fairly broad prof...

  4. Box- and peanut-shaped bulges. III. A new class of bulges: Thick Boxy Bulges

    E-Print Network [OSTI]

    R. Luetticke; M. Pohlen; R. -J. Dettmar

    2004-01-06

    Inspecting all 1224 edge-on disk galaxies larger than 2' in the RC3 on DSS images we have found several galaxies with extraordinary bulges meeting two criteria: They are box shaped and large in respect to the diameters of their galaxies. These bulges are often disturbed, show frequently prominent irregularities and asymmetries, and some possess possible merger remnants or merging satellites. For these bulges we have introduced the term "Thick Boxy Bulges" (TBBs). About 2% of all disk galaxies (S0-Sd), respectively 4% of all galaxies with box- and peanut-shaped (b/p) bulges, belong to this class of galaxies. Using multicolour CCD and NIR data we have enlarged and followed up our sample of nearly 20 galaxies with a TBB. The disturbed morphology of a large fraction of these galaxies shows that many of the TBB galaxies are not dynamically settled. For the TBBs the extent of the box shape seems to be too large to result from a normal bar potential. Therefore we conclude that two classes of b/p bulges exist with different origins. While most (~96%) b/p bulges can be explained by bars alone, the extended boxy structures of TBBs result most likely from accreted material by infalling satellite companions (soft merging).

  5. Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

    E-Print Network [OSTI]

    M. Osipenko; M. Ripani; R. Alba; G. Ricco; M. Barbagallo; P. Boccaccio; A. Celentano; N. Colonna; L. Cosentino; A. Del Zoppo; A. Di Pietro; J. Esposito; P. Figuera; P. Finocchiaro; A. Kostyukov; C. Maiolino; D. Santonocito; M. Schillaci; V. Scuderi; C. M. Viberti

    2013-06-28

    The design of a low-power prototype of neutron amplifier recently proposed within the INFN-E project indicated the need for more accurate called for detailed data on the neutron yield produced by a proton beam with energy of about 70 MeV impinging on a thick Beryllium target. Such measurement was performed at the LNS superconducting cyclotron, covering a wide angular range from 0 to 150 degrees and a complete neutron energy interval from thermal to beam energy. Neutrons with energy above 0.5 MeV were measured by liquid scintillators exploiting their Time of Flight to determine the kinetic energy. For lower energy neutrons, down to thermal energy, a $^3$He detector was used. The obtained data are in good agreement with previous measurements at 0 degree with 66 MeV proton beam, covering neutron energies >10 MeV, as well as with measurements at few selected angles with protons of 46, 55 and 113 MeV energy. The present results extend the neutron yield data in the 60-70 MeV beam energy range. A comparison of measured yields to MCNP and Geant4 Monte Carlo simulations was performed.

  6. Proceedings of the 19th Central Hardwood Forest Conference GTR-NRS-P-142 283 eSTIMATING bARk THICkNeSSeS oF CoMMoN

    E-Print Network [OSTI]

    , estimate the volume of solid wood available. Determining the volume or weight of bark for a log including mulch, charcoal filters, as a source of tannins for leather and textile processing, or as boiler fuel. Knowing the thickness of bark along the stem is critical in order to accurately estimate bark

  7. 5m, 10m and 20m post arrays in a 50m thick film. High aspect ratio imaging

    E-Print Network [OSTI]

    Zahn, Jeffrey

    walls Near UV (350-400nm) processing Improved coating properties Uniformity (lower surface tension for many years. By using a faster drying, more polar solvent system, improved coating properties and higher throughput are realized. .ilm thicknesses of 0.5 to >200mm can be achieved with a single coat process

  8. Improved hole distribution in InGaN/GaN light-emitting diodes with graded thickness quantum barriers

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    is 48.3%. Moreover, the light output power was enhanced from 770 mW for the ETQB LEDs to 870 m; accepted 3 June 2013; published online 19 June 2013) InGaN/GaN light-emitting diodes (LEDs) with graded , which is much smaller than that of the conventional equal-thickness quantum barriers (ETQB) LED, which

  9. 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.

  10. 06/27/2000 47th AVS International Symposium 1 W-CVD Film Thickness Metrology and Process

    E-Print Network [OSTI]

    Rubloff, Gary W.

    06/27/2000 47th AVS International Symposium 1 W-CVD Film Thickness Metrology and Process Control Engineering University of Maryland, College Park, MD 20742 #12;06/27/2000 47th AVS International Symposium 2 application for real-time control experiments #12;06/27/2000 47th AVS International Symposium 3 H2 Reduction W

  11. Observations of ice thickness and frazil ice in the St. Lawrence Island polynya from satellite imagery, upward looking sonar, and

    E-Print Network [OSTI]

    Washington at Seattle, University of

    with meteorological observations and a heat flux model. South of the island, we compare the ULS and thermalObservations of ice thickness and frazil ice in the St. Lawrence Island polynya from satellite, this paper examines the behavior of the Bering Sea St. Lawrence Island polynya using a combination

  12. Thickness monitoring of graphene on SiC using low-energy electron diffraction P. J. Fisher

    E-Print Network [OSTI]

    Feenstra, Randall

    more general method. A series of samples are prepared by vacuum annealing in a graphene production system (suitable for graphene preparation on semi- insulating SiC, and scalable to large wafer sizes1 Thickness monitoring of graphene on SiC using low-energy electron diffraction P. J. Fisher IBM T

  13. Analysis of optical response of long period fiber gratings to nm-thick thin-film coatings

    E-Print Network [OSTI]

    Heflin, Randy

    and experimentally demonstrated that the resonant wavelength of long period fiber gratings (LPG) can be shifted of the film and/or the variation of its refractive index. These results demonstrate the sensitivity of LPG devices and high-performance index/thickness-sensing LPG-based fiber sensors for detecting optical

  14. Measuring large topographic change with InSAR: Lava thicknesses, extrusion rate and subsidence rate at Santiaguito volcano, Guatemala

    E-Print Network [OSTI]

    Elliott, John

    at Santiaguito volcano, Guatemala S.K. Ebmeier a,n , J. Biggs b , T.A. Mather a , J.R. Elliott a , G. Wadge c , F. We apply this to Santiaguito volcano, Guatemala, and measure increases in lava thickness of up to 140

  15. TOWARDS CIGS SOLAR CELLS WITH REDUCED FILM THICKNESS: A STUDY OF OPTICAL PROPERTIES AND OF PHOTONIC STRUCTURES FOR LIGHT TRAPPING

    E-Print Network [OSTI]

    TOWARDS CIGS SOLAR CELLS WITH REDUCED FILM THICKNESS: A STUDY OF OPTICAL PROPERTIES AND OF PHOTONIC ABSTRACT: In view of large-scale exploitation of CuIn1-xGaxSe2 (CIGS) solar cells for photovoltaic energy. In this work we perform a full study of optical properties of CIGS solar cells grown by a hybrid sputtering

  16. Signicance of sample thickness and surface segregation on the electrical conductivity of Wesgo AL995 alumina under ITER

    E-Print Network [OSTI]

    Howlader, Matiar R

    are expected to be used in fusion reactors like international thermonuclear experimental reactor (ITER insulating material in fusion reactors [1] because of its high thermal conductivity [2], high resistance of alumina are to be used in fusion reactors, no studies have ever been done on the thickness dependence

  17. Investigation of annealing effects and film thickness dependence of polymer solar cells based on poly,,3-hexylthiophene...

    E-Print Network [OSTI]

    Investigation of annealing effects and film thickness dependence of polymer solar cells based shown the possibility of putting them into practical applica- tions. Polymeric solar cells based progress in improving pho- tovoltaic cell efficiency.6­9 Among these D/A systems, poly 3-hexylthiophene P3

  18. Skew light propagation in optically thick optical pumping cells B. Chann, E. Babcock, L. W. Anderson, and T. G. Walker

    E-Print Network [OSTI]

    Walker, Thad G.

    Skew light propagation in optically thick optical pumping cells B. Chann, E. Babcock, L. W Received 25 March 2002; published 27 September 2002 Circularly polarized light propagating at an angle-exchange optical pumping experiments. This causes excess absorption of the pumping light that can significantly

  19. Effect of shell thickness on small-molecule solar cells enhanced by dual plasmonic gold-silica nanorods

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    of a small-molecule organic solar cell. At optimal (1 wt. %) concentration, Au-silica nanorods with 5 nm. [http://dx.doi.org/10.1063/1.4896516] Plasmonic organic solar cells (OSCs) have been inten- sivelyEffect of shell thickness on small-molecule solar cells enhanced by dual plasmonic gold

  20. Nuclear matter symmetry energy and the neutron skin thickness of heavy nuclei RID A-2398-2009 

    E-Print Network [OSTI]

    Chen, LW; Ko, Che Ming; Li, Ba.

    2005-01-01

    Correlations between the thickness of the neutron skin in finite nuclei and the nuclear matter symmetry energy are studied in the Skyrme Hartree-Fock model. From the most recent analysis of the isospin diffusion data in heavy-ion collisions based...

  1. 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 900°C using three approaches to verify NETL's previously reported transient H2S exposure results. 100 um thick braze-mounted foils failed prior to 600°C 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 350°C 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.

  2. Masticatory biomechanics and its relevance to early hominid phylogeny: An examination of palatal thickness using finite-element analysis

    E-Print Network [OSTI]

    thickness using finite-element analysis David S. Strait a,*, Brian G. Richmond b , Mark A. Spencer c which early hominid features are functionally related to chewing. This paper uses finite-element Paranthropus synapomorphies putatively related to mastication. A finite-element model of 145,680 elements

  3. An amalgamated meter-thick sedimentary package enabled by the 2011 Tohoku tsunami in El Garrapatero, Galapagos Islands

    E-Print Network [OSTI]

    Lynett, Patrick

    An amalgamated meter-thick sedimentary package enabled by the 2011 Tohoku tsunami in El Garrapatero: Received 23 April 2012 Available online 21 May 2013 Keywords: Tsunami deposits Coastal morphology Natural hazards Tsunamis and storms instigate sedimentological and geomorphological changes to the coastal system

  4. Effects of thickness and cycle parameters on fretting wear behavior of CVD diamond coatings on steel substrates

    E-Print Network [OSTI]

    Bristol, University of

    , mechanical seals, cutting tools, and gears. Well-adhered diamond films deposited on steel surfaces can leadEffects of thickness and cycle parameters on fretting wear behavior of CVD diamond coatings) methods. A Co-containing tungsten-carbide coating prepared by high velocity oxy-fuel spraying was used

  5. Vapor deposition on doublet airfoil substrates: Coating thickness control Theron M. Rodgers, Hengbei Zhao, and Haydn N. G. Wadleya)

    E-Print Network [OSTI]

    Wadley, Haydn

    barrier coatings (TBCs) to gas turbine engine components,1­6 wear-resistant coatings to cutting tools,7Vapor deposition on doublet airfoil substrates: Coating thickness control Theron M. Rodgers to coatings on interior surfaces of the doublet airfoil geometry, which are only accessible through

  6. Hybrid glass coatings for optical fibers: effect of coating thickness on strength and dynamic fatigue characteristics of silica fibers

    E-Print Network [OSTI]

    Matthewson, M. John

    Hybrid glass coatings for optical fibers: effect of coating thickness on strength and dynamic coatings. Recently developed sol-gel derived inorganic- organic hybrid materials called hybrid glass offered improved protective performance as compared to standard dual polymer coated fibers [1

  7. Constraints on Moho depth and crustal thickness in the Liguro-Provencal basin from a 3D gravity inversion: geodynamic

    E-Print Network [OSTI]

    Nicolas, Chamot-Rooke

    Constraints on Moho depth and crustal thickness in the Liguro- Provencal basin from a 3D gravity~ologie, CNRS-URA 1316, Ecole Normale Sup&ieure, 24 rue Lhomond, 75231 Paris Cedex 05, France (e-mail: rooke and reflection data to constrain a new Moho depth map in the Liguro-Proven~al basin (Western Mediterranean Sea

  8. ULTRA-LIGHTWEIGHT AMORPHOUS SILICON SOLAR CELLS DEPOSITED OIN 7.5pn-1 THICK STAINLESS STEEL SUBSTRATES

    E-Print Network [OSTI]

    Deng, Xunming

    ULTRA-LIGHTWEIGHT AMORPHOUS SILICON SOLAR CELLS DEPOSITED OIN 7.5pn-1 THICK STAINLESS STEEL specific power for space application, we deposited a-Si thin film solar cells on ultra-thin stainless steel-thin stainless steel (SS) substrates (down to 7.5 pm) for space power applications. In this paper, we report our

  9. 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 con

  10. 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

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

    SciTech Connect (OSTI)

    Lee, Jeongwoo [Physics Department, New Jersey Institute of Technology, Newark, NJ 07102 (United States); Lim, Daye; Choe, G. S.; Kim, Kap-Sung [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Jang, Minhwan [Department of Astronomy and Space Science, Kyung Hee University, Yongin 446-701 (Korea, Republic of)

    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.

  12. Numerical relativity simulations of thick accretion disks around tilted Kerr black holes

    E-Print Network [OSTI]

    Vassilios Mewes; José A. Font; Filippo Galeazzi; Pedro J. Montero; Nikolaos Stergioulas

    2015-06-12

    In this work we present 3D numerical relativity simulations of thick accretion disks around {\\it tilted} Kerr black holes. We investigate the evolution of three different initial disk models with a range of initial black hole spin magnitudes and tilt angles. For all the disk-to-black hole mass ratios considered ($0.044-0.16$) we observe significant black hole precession and nutation during the evolution. This indicates that for such mass ratios, neglecting the self-gravity of the disks by evolving them in a fixed background black hole spacetime is not justified. We find that the two more massive models are unstable against the Papaloizou-Pringle (PP) instability and that those PP-unstable models remain unstable for all initial spins and tilt angles considered, showing that the development of the instability is a very robust feature of such PP-unstable disks. The tilt between the black hole spin and the disk is strongly modulated during the growth of the PP instability, causing a partial global realignment of black hole spin and disk angular momentum in the most massive model with constant specific angular momentum $l$. For the model with non-constant $l$-profile we observe a long-lived $m=1$ non-axisymmetric structure which shows strong oscillations of the tilt angle in the inner regions of the disk. We attribute this effect to the development of Kozai-Lidov oscillations. Our simulations also confirm earlier findings that the development of the PP instability causes the long-term emission of large amplitude gravitational waves, predominantly for the $l=m=2$ multipole mode. The imprint of the BH precession on the gravitational waves from tilted BH-torus systems remains an interesting open issue that would require significantly longer simulations than those presented in this work.

  13. Neutron energy spectrum from 120 GeV protons on a thick copper target

    E-Print Network [OSTI]

    Nobuhiro Shigyo; Toshiya Sanami; Tsuyoshi Kajimoto; Yosuke Iwamoto; Masayuki Hagiwara; Kiwamu Saito; Kenji Ishibashi; Hiroshi Nakashima; Yukio Sakamoto; Hee-Seock Lee; Erik Ramberg; Aria A. Meyhoefer; Rick Coleman; Doug Jensen; Anthony F. Leveling; David J. Boehnlein; Nikolai V. Mokhov

    2012-02-07

    Neutron energy spectrum from 120 GeV protons on a thick copper target was measured at the Meson Test Beam Facility (MTBF) at Fermi National Accelerator Laboratory. The data allows for evaluation of neutron production process implemented in theoretical simulation codes. It also helps exploring the reasons for some disagreement between calculation results and shielding benchmark data taken at high energy accelerator facilities, since it is evaluated separately from neutron transport. The experiment was carried out using a 120 GeV proton beam of 3E5 protons/spill. Since the spill duration was 4 seconds, proton-induced events were counted pulse by pulse. The intensity was maintained using diffusers and collimators installed in the beam line to MTBF. The protons hit a copper block target the size of which is 5cm x 5cm x 60 cm long. The neutrons produced in the target were measured using NE213 liquid scintillator detectors, placed about 5.5 m away from the target at 30^{\\circ} and 5 m 90^{\\circ} with respect to the proton beam axis. The neutron energy was determined by time-of-flight technique using timing difference between the NE213 and a plastic scintillator located just before the target. Neutron detection efficiency of NE213 was determined on basis of experimental data from the high energy neutron beam line at Los Alamos National Laboratory. The neutron spectrum was compared with the results of multi-particle transport codes to validate the implemented theoretical models. The apparatus would be applied to future measurements to obtain a systematic data set for secondary particle production on various target materials.

  14. 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.

  15. 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.

  16. 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.

  17. Influence of CdTe thickness on structural and electrical properties of CdTe/CdS solar cells

    E-Print Network [OSTI]

    Romeo, Alessandro

    Influence of CdTe thickness on structural and electrical properties of CdTe/CdS solar cells A a b s t r a c ta r t i c l e i n f o Available online xxxx Keywords: Solar cells CdCl2 CdTe Thin absorbers Due to its high scalability and low production cost, CdTe solar cells have shown a very strong

  18. Probing the neutron-skin thickness by photon production from reactions induced by intermediate-energy protons

    E-Print Network [OSTI]

    Wei, Gao-Feng

    2015-01-01

    Photon from neutron-proton bremsstrahlung in p+Pb reactions is examined as a potential probe of the neutron-skin thickness in different centralities and at different proton incident energies. It is shown that the best choice of reaction environment is about 140MeV for the incident proton and the 95\\%-100\\% centrality for the reaction system since the incident proton mainly interacts with neutrons inside the skin of the target and thus leads to different photon production to maximal extent. Moreover, considering two main uncertainties from both photon production probability and nucleon-nucleon cross section in the reaction, I propose to use the ratio of photon production from two reactions to measure the neutron-skin thickness because of its cancellation effects on these uncertainties simultaneously, but the preserved about 13\\%-15\\% sensitivities on the varied neutron-skin thickness from 0.1 to 0.3fm within the current experimental uncertainty range of the neutron-skin size in $^{208}$Pb.

  19. High quality Y-type hexaferrite thick films for microwave applications by an economical and environmentally benign crystal growth technique

    SciTech Connect (OSTI)

    Hu, Bolin; Chen, Yajie, E-mail: y.chen@neu.edu; Gillette, Scott; Su, Zhijuan; Harris, Vincent G. [Center for Microwave Magnetic Materials and Integrated Circuits and Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States); Wolf, Jason; McHenry, Michael E. [Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States)

    2014-02-17

    Thick barium hexaferrite Ba{sub 2}Zn{sub 2}Fe{sub 12}O{sub 22} (i.e., Zn{sub 2}Y) films having thicknesses of ?100??m were epitaxially grown on MgO (111) substrates using an environmentally benign ferrite-salt mixture by vaporizing the salt. X-ray diffraction pole figure analyses showed (00l) crystallographic alignment with little in plane dispersion confirming epitaxial growth. Saturation magnetization, 4?M{sub s}, was measured for as-grown films to be 2.51?±?0.1?kG with an out of plane magnetic anisotropy field H{sub A} of 8.9?±?0.1?kOe. Ferromagnetic resonance linewidth, as the peak-to-peak power absorption derivative at 9.6?GHz, was measured to be 62?Oe. These properties demonstrate a rapid, convenient, cost-effective, and nontoxic method of growing high quality thick crystalline ferrite films which could be used widely for microwave device applications.

  20. Epitaxial {tau} phase MnAl thin films on MgO (001) with thickness-dependent magnetic anisotropy

    SciTech Connect (OSTI)

    Cui Yishen; Chen Wei [Department of Physics, University of Virginia, Charlottesville, Virginia 22904 (United States); Yin Wenjing; Lu Jiwei [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Wolf, Stuart A. [Department of Physics, University of Virginia, Charlottesville, Virginia 22904 (United States); Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2011-11-15

    In this study, ferromagnetic MnAl films were prepared by alternating Al/Mn quasi-monolayer deposition using a novel biased target ion beam deposition (BTIBD) technique. XRD results showed that the magnetic {tau} phase was well formed in MnAl thin films ({approx}10 nm), which grew epitaxially on single crystal MgO (001) substrates. The optimized saturation magnetization was {approx}394 emu/cc. Furthermore, we observed a thickness-dependent uniaxial anisotropy in ferromagnetic MnAl films, which was attributed to the change of the tetragonal lattice distortion as a function of film thickness. The relationship between the film thicknesses and saturation magnetizations suggested the existence of a magnetically dead layer {approx}2.7 nm with an extrapolated saturation moment around 523 emu/cc ({approx}1.90 {mu}{sub B}/Mn). This value has exceeded the experimental value in bulk materials and is close to the theoretically predicted magnetization ({approx}1.975 {mu}{sub B}/Mn).

  1. 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

  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. Roughly 15,000 patents a month are issued by the US Patent and Trademark Office (PTO).1 By law, these are supposed to cover only "novel" and "nonobvious" inventions, but an average

    E-Print Network [OSTI]

    Sadoulet, Elisabeth

    1347 Roughly 15,000 patents a month are issued by the US Patent and Trademark Office (PTO).1 By law­20 hours of patent examiner time,2 and a substantial proportion of the few patents later fully evaluated the issuance of many ques- tionable patents. Responding to such concerns, the Supreme Court recently made

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

    DOE Patents [OSTI]

    Levesque, Daniel (Terrebonne, CA); Moreau, Andre (St-Bruno-de-Montarville, CA); Dubois, Marc (Montreal, CA); Monchalin, Jean-Pierre (Montreal, CA); Bussiere, Jean (St-Bruno, CA); Lord, Martin (Beloeil, CA); Padioleau, Christian (Montreal, CA)

    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.

  5. Geometric frequency shift for electric dipole searches with trapped spin-1/2 particles in general fields and measurement cells of arbitrary shape with smooth or rough walls

    E-Print Network [OSTI]

    A. Steyerl; C. Kaufman; G. Müller; R. Golub

    2015-05-13

    The important role of geometric phases in searches for a permanent electric dipole moment of the neutron, using Ramsey separated oscillatory field nuclear magnetic resonance, was first investigated by Pendlebury $\\textit{et al.}$ [Phys. Rev. A $\\mathbf{70}$, 032102 (2004)]. Their analysis was based on the Bloch equations. In subsequent work using the spin density matrix Lamoreaux and Golub [Phys. Rev. A $\\mathbf{71}$, 032104 (2005)] showed the usual relation between the frequency shifts and the correlation functions of the fields seen by trapped particles in general fields (Redfield theory). More recently we presented a solution of the Schr\\"odinger equation for spin-$1/2$ particles in circular cylindrical traps with smooth walls and exposed to arbitrary fields [Steyerl $\\textit{et al.}$, Phys.Rev. A $\\mathbf{89}$, 052129 (2014)]. Here we extend this work to show how the Redfield theory follows directly from the Schr\\"odinger equation solution and include wall roughness, cylindrical trap geometry with arbitrary cross section, and field perturbations that do not, in the frame of the moving particles, average to zero in time and which, therefore, do not satisfy the prerequisites of the statistical approach based on the spin-density matrix. We show by direct, detailed, calculation the agreement of the results from the Schr\\"odinger equation with the Redfield theory for the cases of a rectangular cell with specular walls and of a circular cell with diffuse reflecting walls.

  6. Pressure-dependent transition from atoms to nanoparticles in magnetron sputtering: Effect on WSi{sub 2} film roughness and stress

    SciTech Connect (OSTI)

    Zhou Lan; Wang Yiping; Zhou Hua; Li Minghao; Headrick, Randall L.; MacArthur, Kimberly; Shi Bing; Conley, Ray; Macrander, Albert T. [Department of Physics and Materials Science Program, University of Vermont, Burlington, Vermont 05405 (United States); Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2010-08-15

    We report on the transition between two regimes from several-atom clusters to much larger nanoparticles in Ar magnetron sputter deposition of WSi{sub 2}, and the effect of nanoparticles on the properties of amorphous thin films and multilayers. Sputter deposition of thin films is monitored by in situ x-ray scattering, including x-ray reflectivity and grazing incidence small-angle x-ray scattering. The results show an abrupt transition at an Ar background pressure P{sub c}; the transition is associated with the threshold for energetic particle thermalization, which is known to scale as the product of the Ar pressure and the working distance between the magnetron source and the substrate surface. Below P{sub c} smooth films are produced while above P{sub c} roughness increases abruptly, consistent with a model in which particles aggregate in the deposition flux before reaching the growth surface. The results from WSi{sub 2} films are correlated with in situ measurement of stress in WSi{sub 2}/Si multilayers, which exhibits a corresponding transition from compressive to tensile stress at P{sub c}. The tensile stress is attributed to coalescence of nanoparticles and the elimination of nanovoids.

  7. Diversities in the properties of neutron stars at a fixed neutron-skin thickness in $^{208}$Pb nucleus

    E-Print Network [OSTI]

    N. Alam; A. Sulaksono; B. K. Agrawal

    2015-07-03

    We study the diversities in the properties of the neutron stars arising due to the different choices for the cross-coupling between various mesons which governs the density dependence of the nuclear symmetry energy in the extended relativistic mean-field(RMF) model. For this purpose, we obtain two different families of the extended RMF model corresponding to different non-linear cross-coupling term in the isovector part of the effective Lagrangian density. The lowest order contributions for the $\\delta$ mesons are also included. The different models within the same family are so obtained that they yield wide variation in the value of neutron-skin thickness in the $^{208}$Pb nucleus. These models are employed to compute the neutron star properties such as, core-crust transition density, radius and red shift at canonical mass ($1.4M_{\\odot}$), tidal polarizability parameter, and threshold mass required for the enhanced cooling through direct Urca process. Most of the neutron star properties considered are significantly different(10\\%-40\\%) for the different families of models at a smaller neutron-skin thickness ($\\sim 0.15$ fm) in the $^{208}$Pb nucleus.

  8. Exploring the connection between coronal and footpoint sources in a thin-thick target solar flare model

    E-Print Network [OSTI]

    Marina Battaglia; Arnold O. Benz

    2007-02-12

    Context: Hard X-ray emission of coronal sources in solar flares has been observed and studied since its discovery in Yohkoh observations. Several models have been proposed to explain the physical mechanisms causing this emission and the relations between those sources and simultaneously observed footpoint sources. Aims: We investigate and test one of the models (intermediate thin-thick target model) developed on the basis of Yohkoh observations. The model makes precise predictions on the shape of coronal and footpoint spectra and the relations between them, that can be tested with new instruments such as RHESSI. Methods: RHESSI observations of well observed events are studied in imaging and spectroscopy and compared to the predictions from the intermediate thin-thick target model. Results: The results indicate that such a simple model cannot account for the observed relations between the non-thermal spectra of coronal and footpoint sources. Including non-collisional energy loss of the electrons in the flare loop due to an electric field can solve most of the inconsistencies.

  9. Pavement roughness on expansive clays 

    E-Print Network [OSTI]

    Velasco, Manuel O

    1980-01-01

    available weather station data over 20 years. b The roadway sections within this area are located in two different counties. IQ O'I CC O O 0 O CA O c I I- I/I I/I 0 0 0 0 0 /Q Ql 0 0 Z I/I C/I I/I IO 3: Z Z E tJJ Ql 0 O 0 I/I 0 CL m IQ QI... L Qt O V '?C Ct J N ~K 0 Vl ' /U 3 Ct I/I O Ct V E IU UD l- CU O V I CZI IU J O V N tV E Qt IJ- 0 3: C I/I O IU V E tll 5- N CU CJ X N tt- IL 0 Vl ' CU I/I O IU ' V E IU l- Cl N IU C J D N tt- U 0 I/I CJ I/I O...

  10. Controlled Rough Paths on Manifolds

    E-Print Network [OSTI]

    Semko, Jeremy

    2015-01-01

    23] L. C. Young, An inequality of H¨older type connectedI. An extension of an inequality of L. C. Young, Math. Res.now that p Inequality (see [23]) along with an

  11. Drying Rough Rice in Storage. 

    E-Print Network [OSTI]

    Sorenson, J. W. Jr.; Crane, L. E.

    1960-01-01

    feet columna erating schedule is drying at a rate fast enou 7.2 8 1.80 to prevent mold development. Another importa : 10 3.00 consideration is simplicity of operating instrr : 9.0 8 2.50 tions requiring a minimumjof supervision of i ( 10 4....25 drying operation. Other desirable features in : 10.8 6 1.80 fan operating schedule are maximum drying eE : 8 3.25 ciency and use of minimum air flow rates. . 'Based on data presented by C. K. Shedd (2). The direction of air movement through ri a...

  12. Fundamental Mechanisms of Interface Roughness

    SciTech Connect (OSTI)

    Randall L. Headrick

    2009-01-06

    Publication quality results were obtained for several experiments and materials systems including: (i) Patterning and smoothening of sapphire surfaces by energetic Ar+ ions. Grazing Incidence Small Angle X-ray Scattering (GISAXS) experiments were performed in the system at the National Synchrotron Light Source (NSLS) X21 beamline. Ar+ ions in the energy range from 300 eV to 1000 eV were used to produce ripples on the surfaces of single-crystal sapphire. It was found that the ripple wavelength varies strongly with the angle of incidence of the ions, which increase significantly as the angle from normal is varied from 55° to 35°. A smooth region was found for ion incidence less than 35° away from normal incidence. In this region a strong smoothening mechanism with strength proportional to the second derivative of the height of the surface was found to be responsible for the effect. The discovery of this phase transition between stable and unstable regimes as the angle of incidence is varied has also stimulated new work by other groups in the field. (ii) Growth of Ge quantum dots on Si(100) and (111). We discovered the formation of quantum wires on 4° misoriented Si(111) using real-time GISAXS during the deposition of Ge. The results represent the first time-resolved GISAXS study of Ge quantum dot formation. (iii) Sputter deposition of amorphous thin films and multilayers composed of WSi2 and Si. Our in-situ GISAXS experiments reveal fundamental roughening and smoothing phenomena on surfaces during film deposition. The main results of this work is that the WSi2 layers actually become smoother during deposition due to the smoothening effect of energetic particles in the sputter deposition process.

  13. Analysis of Chemical Storage and Transit Times to Characterize Water Movement Through a Thick Unsaturated Zone Overlying the High Plains Aquifer, Northwestern Kansas

    E-Print Network [OSTI]

    Katz, Britney S.

    2014-12-31

    not associated to precipitation or pumping. This indicated a previously unknown source of recharge to the aquifer and the need to further investigate water movement processes through the thick unsaturated zone above it. The roles of irrigation, land use...

  14. 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 0.5–6 cm. For a fixed compensator thickness, variation of the ?{sub eff} with the field size ranged from 3.7–6.8%, 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 0.5–6 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}.

  15. An effect of the networks of the subgrain boundaries on spectral responses of thick CdZnTe detectors

    SciTech Connect (OSTI)

    Bolotnikov, A.; Butcher, J.; Camarda, G.; Cui, Y.; Egarievwe, S.; Fochuk, P.; Gul,R.; Hamade, M.; Hossain, A.; Kim, K.; Kopach,O.; Petryk, M.; Raghothamachar, B.; Yang, G.; and James, R.B.

    2011-08-12

    CdZnTe (CZT) crystals used for nuclear-radiation detectors often contain high concentrations of subgrain boundaries and networks of poligonized dislocations that can significantly degrade the performance of semiconductor devices. These defects exist in all commercial CZT materials, regardless of their growth techniques and their vendor. We describe our new results from examining such detectors using IR transmission microscopy and white X-ray beam diffraction topography. We emphasize the roles on the devices performances of networks of subgrain boundaries with low dislocation densities, such as poligonized dislocations and mosaic structures. Specifically, we evaluated their effects on the gamma-ray responses of thick, >10 mm, CZT detectors. Our findings set the lower limit on the energy resolution of CZT detectors containing dense networks of subgrain boundaries, and walls of dislocations.

  16. Effect of antiferromagnetic layer thickness on exchange bias, training effect, and magnetotransport properties in ferromagnetic/antiferromagnetic antidot arrays

    SciTech Connect (OSTI)

    Gong, W. J.; Liu, W., E-mail: wliu@imr.ac.cn; Feng, J. N.; Zhang, Z. D. [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Kim, D. S.; Choi, C. J. [Functional Materials Division, Korea Institute of Materials Science, 531 Changwon- daero, Changwon 631-831 (Korea, Republic of)

    2014-04-07

    The effect of antiferromagnetic (AFM) layer on exchange bias (EB), training effect, and magnetotransport properties in ferromagnetic (FM) /AFM nanoscale antidot arrays and sheet films Ag(10?nm)/Co(8?nm)/NiO(t{sub NiO})/Ag(5?nm) at 10?K is studied. The AFM layer thickness dependence of the EB field shows a peak at t{sub NiO}?=?2?nm that is explained by using the random field model. The misalignment of magnetic moments in the three-dimensional antidot arrays causes smaller decrease of EB field compared with that in the sheet films for training effect. The anomalous magnetotransport properties, in particular positive magnetoresistance (MR) for antidot arrays but negative MR for sheet films are found. The training effect and magnetotransport properties are strongly affected by the three-dimensional spin-alignment effects in the antidot arrays.

  17. Electric dipole response of 208Pb from proton inelastic scattering: constraints on neutron skin thickness and symmetry energy

    E-Print Network [OSTI]

    A. Tamii; P. von Neumann-Cosel; I. Poltoratska

    2013-10-02

    The electric dipole (E1) response of 208Pb has been precisely determined by measuring Coulomb excitation induced by proton scattering at very forward angles. The electric dipole polarizability, defined as inverse energy-weighted sum rule of the E1 strength, has been extracted as 20.1+-0.6 fm^3. The data can be used to constrain the neutron skin thickness of 208Pb to 0.168(+-0.009)_expt(+-0.013)_theo(+-0.021)_est fm, where the subscript "expt" refers to the experimental uncertainty, "theor" to the theoretical confidence band and "est" to the uncertainty associated with the estimation of the symmetry energy at the saturation density. In addition, a constraint band has been extracted in the plane of the symmetry energy (J) and its slope parameter (L) at the saturation density.

  18. Structure and properties of nanocrystalline ZrN{sub x}O{sub y} thin films: Effect of the oxygen content and film thickness

    SciTech Connect (OSTI)

    Lan, Kuan-Che; Hunag, Jia-Hong; Ai, Chi-Fong; Yu, Ge-Ping [Department of Engineering and System Science, National Tsing Hua University, 101 Kuang Fu Rd., Sec. 2, Hsinchu, 300 Taiwan (China); Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, 325 Taiwan (China); Department of Engineering and System Science, National Tsing Hua University, 101 Kuang Fu Rd., Sec. 2, Hsinchu, 300 Taiwan (China) and Institute of Nuclear Engineering and Science, 101 Kuang Fu Rd., Sec. 2, Hsinchu, 300 Taiwan (China)

    2011-05-15

    The main objective of this study was to investigate the structure and properties of ZrN{sub x}O{sub y} thin films associated with oxygen content and film thickness. ZrN{sub x}O{sub y} thin films were deposited using hollow cathode discharge ion plating on Si (100) substrate. The thickness of ZrN{sub x}O{sub y} films increased with increasing oxygen flow rate, ranging from 143 to 894 nm. Phase separation from ZrN{sub x}O{sub y} to ZrN and monoclinic ZrO{sub 2} (m-ZrO{sub 2}) was observed by x-ray diffraction (XRD). The electrical and mechanical properties were influenced by the film thickness and the amount of separated phase, m-ZrO{sub 2}. ZrN{sub x}O{sub y} thin films with smaller thickness or deposited at higher O{sub 2} flow rate were found to have higher electrical resistivity. Hardness of the ZrN{sub x}O{sub y} thin films increased with increasing thickness, which could be related to microstructure change of the thin films. Residual stress of the ZrN phase in the ZrN{sub x}O{sub y} thin films, measured using the modified sin{sup 2} {psi} XRD method, decreased with increasing oxygen flow rate. The thickness dependence of the residual stress in ZrN was different with different oxygen flow rates. The average residual stress of the ZrN{sub x}O{sub y} thin films also decreased with increasing oxygen flow rate and the stress did not showed significant dependence on the film thickness.

  19. Wind tunnel simulation of wind effects and associated displacement hazards on flat surface construction materials such as plywood 

    E-Print Network [OSTI]

    Madeley, Jack T.

    1996-01-01

    decking material with the air stream flowing over the stack until top sheet separated or lifted from the stack. Next, a half-scale model was placed in the test section of the tunnel with pressure ports attached to a high speed sampling transducer...

  20. Reliable Identification of Compton-thick Quasars at z~2: Spitzer Mid-IR spectroscopy of HDF-oMD49

    E-Print Network [OSTI]

    D. M. Alexander; R. R. Chary; A. Pope; F. E. Bauer; W. N. Brandt; E. Daddi; M. Dickinson; D. Elbaz; N. A. Reddy

    2008-07-15

    Many models that seek to explain the origin of the unresolved X-ray background predict that Compton-thick Active Galactic Nuclei (AGNs) are ubiquitious at high redshift. However, few distant Compton-thick AGNs have been reliably identified to date. Here we present Spitzer-IRS spectroscopy and 3.6-70um photometry of a z=2.2 optically identified AGN (HDF-oMD49) that is formally undetected in the 2Ms Chandra Deep Field-North (CDF-N) survey. The Spitzer-IRS spectrum and spectral energy distribution of this object is AGN dominated, and a comparison of the energetics at X-ray wavelengths to those derived from mid-infrared (mid-IR) and optical spectroscopy shows that the AGN is intrinsically luminous (L_X~3x10^44 erg/s) but heavily absorbed by Compton-thick material (N_H>>10^24 cm^{-2}); i.e., this object is a Compton-thick quasar. Adopting the same approach that we applied to HDF-oMD49, we found a further six objects at z~2-2.5 in the literature that are also X-ray weak/undetected but have evidence for AGN activity from optical and/or mid-IR spectroscopy, and show that all of these sources are also Compton-thick quasars with L_X>10^44 erg/s. On the basis of the definition of Daddi etal. (2007), these Compton-thick quasars would be classified as mid-IR excess galaxies, and our study provides the first spectroscopic confirmation of Compton-thick AGN activity in a subsample of these z~2 mid-IR bright galaxies. Using the four objects that lie in the CDF-N field, we estimate the space-density of Compton-thick quasars [Phi~(0.7-2.5)x10^-5 Mpc^-3 for L_X>10^44 erg/s objects at z~2-2.5] and show that Compton-thick accretion is as ubiquitious as unobscured accretion in the distant Universe.

  1. 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.

  2. 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

    2015-08-17

    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.

  3. Simultaneous determination of the elastic modulus and density/thickness of ultrathin films utilizing micro-/nanoresonators under applied axial force

    SciTech Connect (OSTI)

    Stachiv, I., E-mail: stachiv@fzu.cz [Institute of Physics, Czech Academy of Sciences, Prague (Czech Republic); Advanced Manufacturing Institute with High-Tech Innovations, National Chung Cheng University, Chiayi County, Taiwan (China); Zapomel, J. [Institute of Thermomechanics, Czech Academy of Sciences, Prague (Czech Republic); Chen, Y.-L. [Institute of Physics, Academia Sinica, Taipei, Taiwan (China); Department of Physics, National Taiwan University, Taipei, Taiwan (China); Department of Chemical Engineering, National Tsing-Hua University, Hsinchu, Taiwan (China)

    2014-03-28

    Thin films are widely used in microelectronics, optics, filters, and various sensing devices. We propose a method to simultaneously determine the elastic modulus and density or thickness of ultrathin films deposited on various substrate materials. This methodology utilizes measurement of the resonant frequencies of the micro-/nanoresonator under intentionally applied axial tension and, consequently, the beam to string transition. Elastic modulus and density/thickness of thin film are obtained from the ratio between the resonant frequencies of the nanoresonator with and without applied axial force.

  4. 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.

  5. 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; Köhler, 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.

  6. Diversities in the properties of neutron stars at a fixed neutron-skin thickness in $^{208}$Pb nucleus

    E-Print Network [OSTI]

    Alam, N; Agrawal, B K

    2015-01-01

    We study the diversities in the properties of the neutron stars arising due to the different choices for the cross-coupling between various mesons which governs the density dependence of the nuclear symmetry energy in the extended relativistic mean-field(RMF) model. For this purpose, we obtain two different families of the extended RMF model corresponding to different non-linear cross-coupling term in the isovector part of the effective Lagrangian density. The lowest order contributions for the $\\delta$ mesons are also included. The different models within the same family are so obtained that they yield wide variation in the value of neutron-skin thickness in the $^{208}$Pb nucleus. These models are employed to compute the neutron star properties such as, core-crust transition density, radius and red shift at canonical mass ($1.4M_{\\odot}$), tidal polarizability parameter, and threshold mass required for the enhanced cooling through direct Urca process. Most of the neutron star properties considered are signi...

  7. 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

  8. 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

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

    SciTech Connect (OSTI)

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

    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.

  10. Measurement of thermal noise in multilayer coatings with optimized layer thickness Akira E. Villar, Eric D. Black, Riccardo DeSalvo, and Kenneth G. Libbrecht

    E-Print Network [OSTI]

    Libbrecht, Kenneth G.

    Measurement of thermal noise in multilayer coatings with optimized layer thickness Akira E. Villar; published 3 June 2010) A standard quarter-wavelength multilayer optical coating will produce the highest reflectivity for a given number of coating layers, but in general it will not yield the lowest thermal noise

  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 3–4 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. In situ thin film thickness measurement with acoustic Lamb waves Jun Pei, F. Levent Degertekin, Butrus T. KhuriYakub, and Krishna C. Saraswat

    E-Print Network [OSTI]

    Khuri-Yakub, Butrus T. "Pierre"

    In situ thin film thickness measurement with acoustic Lamb waves Jun Pei, F. Levent Degertekin-standing highly conducting ultrananocrystalline diamond films with enhanced electron field emission properties gold films Appl. Phys. Lett. 101, 201102 (2012) Effect of N2 dielectric barrier discharge treatment

  13. Spitzer Mid-Infrared Spectroscopy of HDF-oMD49: Reliable Identification of Compton-thick Quasars at z~2

    E-Print Network [OSTI]

    Alexander, D M; Pope, A; Bauer, F E; Brandt, W N; Daddi, E; Dickinson, M; Elbaz, D; Reddy, N A

    2008-01-01

    Many models that seek to explain the origin of the unresolved X-ray background predict that Compton-thick Active Galactic Nuclei (AGNs) are ubiquitious at high redshift. However, few distant Compton-thick AGNs have been reliably identified to date. Here we present Spitzer-IRS spectroscopy and 3.6-70um photometry of a z=2.2 optically identified AGN (HDF-oMD49) that is formally undetected in the 2Ms Chandra Deep Field-North (CDF-N) survey. The Spitzer-IRS spectrum and spectral energy distribution of this object is AGN dominated, and a comparison of the energetics at X-ray wavelengths to those derived from mid-infrared (mid-IR) and optical spectroscopy shows that the AGN is intrinsically luminous (L_X~3x10^44 erg/s) but heavily absorbed by Compton-thick material (N_H>>10^24 cm^{-2}); i.e., this object is a Compton-thick quasar. Adopting the same approach that we applied to HDF-oMD49, we searched the literature and found a further six objects at z~2-2.5 that are also X-ray weak/undetected but have evidence for AG...

  14. Experimental Investigation of the Effect Of Zeolite Coating Thickness on the Performance of a Novel Zeolite-Water Adsorption Heat Pump Module 

    E-Print Network [OSTI]

    Dawoud, B.; Hofle, P.; Chmielewski, S.

    2010-01-01

    is an extruded aluminum finned-tube heat exchanger coated with AQSOA-Z02 zeolite of Mitsubishi Plastics Incorporation (MPI). The effect of the Zeolite layer thickness (300 and 500 micrometers) on the performance of the heat pump module has been experimentally...

  15. 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.

  16. 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.

  17. Intramolecular vibrational energy redistribution from a high frequency mode in the presence of an internal rotor: Classical thick-layer diffusion and quantum localization

    E-Print Network [OSTI]

    Paranjothy Manikandan; Srihari Keshavamurthy

    2007-07-31

    We study the effect of an internal rotor on the classical and quantum intramolecular vibrational energy redistribution (IVR) dynamics of a model system with three degrees of freedom. The system is based on a Hamiltonian proposed by Martens and Reinhardt (J. Chem. Phys. {\\bf 93}, 5621 (1990).) to study IVR in the excited electronic state of para-fluorotoluene. We explicitly construct the state space and show, confirming the mechanism proposed by Martens and Reinhardt, that an excited high frequency mode relaxes via diffusion along a thick layer of chaos created by the low frequency-rotor interactions. However, the corresponding quantum dynamics exhibits no appreciable relaxation of the high frequency mode. We attribute the quantum suppression of the classical thick-layer diffusion to the rotor selection rules and, possibly, dynamical localization effects.

  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 core–sheath 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 anatase–rutile 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 hole–electron 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. Estimations and integral measurements for the spectral yield of neutrons from thick beryllium target bombarded with 16 MeV protons

    E-Print Network [OSTI]

    Fenyvesi, A

    2015-01-01

    Spectral yield of p+Be neutrons emitted by thick (stopping) beryllium target bombarded by 16 MeV protons was estimated via extrapolation of literature data. The spectrum was validated via multi-foil activation method and irradiation of 2N2222 transistors. The hardness parameter (NIEL scaling factor) for displacement damage in bulk silicon was calculated and measured and kappa = 1.26 +- 0.1 was obtained.

  1. Estimations and integral measurements for the spectral yield of neutrons from thick beryllium target bombarded with 16 MeV protons

    E-Print Network [OSTI]

    A. Fenyvesi

    2015-04-28

    Spectral yield of p+Be neutrons emitted by thick (stopping) beryllium target bombarded by 16 MeV protons was estimated via extrapolation of literature data. The spectrum was validated via multi-foil activation method and irradiation of 2N2222 transistors. The hardness parameter (NIEL scaling factor) for displacement damage in bulk silicon was calculated and measured and kappa = 1.26 +- 0.1 was obtained.

  2. The Century Survey Galactic Halo Project III: A Complete 4300 deg^2 Survey of Blue Horizontal Branch Stars in the Metal-Weak Thick Disk and Inner Halo

    E-Print Network [OSTI]

    Warren R. Brown; Timothy C. Beers; Ronald Wilhelm; Carlos Allende Prieto; Margaret J. Geller; Scott J. Kenyon; Michael J. Kurtz

    2007-11-19

    We present a complete spectroscopic survey of 2414 2MASS-selected blue horizontal branch (BHB) candidates selected over 4300 deg^2 of the sky. We identify 655 BHB stars in this non-kinematically selected sample. We calculate the luminosity function of field BHB stars and find evidence for very few hot BHB stars in the field. The BHB stars located at a distance from the Galactic plane |Z|<4 kpc trace what is clearly a metal-weak thick disk population, with a mean metallicity of [Fe/H]= -1.7, a rotation velocity gradient of dv_{rot}/d|Z|= -28+-3.4 km/s in the region |Z|<6 kpc, and a density scale height of h_Z= 1.26+-0.1 kpc. The BHB stars located at 5<|Z|<9 kpc are a predominantly inner-halo population, with a mean metallicity of [Fe/H]= -2.0 and a mean Galactic rotation of -4+-31 km/s. We infer the density of halo and thick disk BHB stars is 104+-37 kpc^-3 near the Sun, and the relative normalization of halo to thick-disk BHB stars is 4+-1% near the Sun.

  3. Physically Gelled Room-Temperature Ionic Liquid-Based Composite Membranes for CO2/N-2 Separation: Effect of Composition and Thickness on Membrane Properties and Performance

    SciTech Connect (OSTI)

    Nguyen, PT; Voss, BA; Wiesenauer, EF; Gin, DL; Nobe, RD

    2013-07-03

    An aspartame-based, low molecular-weight organic gelator (LMOG) was used to form melt-infused and composite membranes with two different imidazolium-based room-temperature ionic liquids (RTILs) for CO2 separation from N-2. Previous work demonstrated that LMOGs can gel RTILs at low, loading levels, and this aspartame-based LMOG was selected because it has been reported to gel a large number of RTILs. The imidazolium-based RTILs were used because of their inherent good properties for CO2/light gas separations. Analysis of the resulting bulk RTIL/LMOG physical gels showed that these materials have high sol-gel transition temperatures (ca. 135 degrees C) suitable for flue gas applications. Gas permeabilities and burst pressure measurements of thick, melt infused membranes revealed a trade-off between high CO2 permeabilities and good mechanical stability as a function of the LMOG loading. Defect-free, composite membranes of the gelled RTILs were successfully fabricated by choosing an appropriate porous membrane support (hydrophobic PTFE) using a suitable coating technique (roller coating). The thicknesses of the applied composite gel layers ranged from 10.3 to 20.7 mu m, which represents an order of magnitude decrease in active layer thickness, compared to the original melt-infused gel RTIL membranes.

  4. Nanoscale selective area growth of thick, dense, uniform, In-rich, InGaN nanostructure arrays on GaN/sapphire template

    SciTech Connect (OSTI)

    Sundaram, S.; El Gmili, Y.; Bonanno, P. L. [CNRS, UMI 2958 Georgia Tech - CNRS, 57070 Metz (France); Puybaret, R.; Li, X.; Voss, P. L.; Ougazzaden, A. [Georgia Institute of Technology, UMI 2958 Georgia Tech - CNRS, 57070 Metz (France); Pantzas, K.; Patriarche, G. [CNRS, UPR LPN, Route de Nozay, 91460 Marcoussis (France); Orsal, G.; Salvestrini, J. P., E-mail: salvestr@metz.supelec.fr [Université de Lorraine, Supélec, LMOPS, EA4423, 57070 Metz (France); Troadec, D. [Université des Sciences et Technologies de Lille, CNRS, UMR 8520 IEMN, 59000 Lille (France); Cai, Z.-H. [Advanced Photon Source, 9700 S. Cass Avenue, Argonne, Illinois 60439 (United States)

    2014-10-28

    Uniform, dense, single-phase, 150?nm thick indium gallium nitride (InGaN) nanostructure (nanorods and nanostripes) arrays have been obtained on gallium nitride templates, by metal organic chemical vapor deposition and nanoscale selective area growth on silicon dioxide patterned masks. The 150?nm thick InGaN nanorods have a perfect hexagonal pyramid shape with relatively homogenous indium concentration up to 22%, which is almost twice as high as in planar InGaN grown in the same condition, and luminesce at 535?nm. InGaN nanostripes feature c-axis oriented InGaN in the core which is covered by InGaN grown along semi-polar facets with higher In content. Transmission electron microscope and sub micron beam X-rays diffraction investigations confirm that both InGaN nanostructures are mostly defect free and monocrystalline. The ability to grow defect-free thick InGaN nanostructures with reduced polarization and high indium incorporation offers a solution to develop high efficiency InGaN-based solar cells.

  5. Epitaxial growth of 100-?m thick M-type hexaferrite crystals on wide bandgap semiconductor GaN/Al{sub 2}O{sub 3} substrates

    SciTech Connect (OSTI)

    Hu, Bolin; Su, Zhijuan; Bennett, Steve; Chen, Yajie, E-mail: y.chen@neu.edu; Harris, Vincent G. [Center for Microwave Magnetic Materials and Integrated Circuits and Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States)

    2014-05-07

    Thick barium hexaferrite BaFe{sub 12}O{sub 19} (BaM) films having thicknesses of ?100??m were epitaxially grown on GaN/Al{sub 2}O{sub 3} substrates from a molten-salt solution by vaporizing the solvent. X-ray diffraction measurement verified the growth of BaM (001) textured growth of thick films. Saturation magnetization, 4?M{sub s}, was measured for as-grown films to be 4.6 ± 0.2 kG and ferromagnetic resonance measurements revealed a microwave linewidth of ?100?Oe at X-band. Scanning electron microscopy indicated clear hexagonal crystals distributed on the semiconductor substrate. These results demonstrate feasibility of growing M-type hexaferrite crystal films on wide bandgap semiconductor substrates by using a simple powder melting method. It also presents a potential pathway for the integration of ferrite microwave passive devices with active semiconductor circuit elements creating system-on-a-wafer architectures.

  6. 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 ?m to a modest 0.50 ?m over an underlying 0.10-?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 ?m/3 ?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 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.

  7. Modeling the effects of fire severity and climate warming on active layer thickness and soil carbon storage of black spruce forests across the landscape in interior Alaska

    SciTech Connect (OSTI)

    Genet, Helene [Institute of Arctic Biology (IAB), University of Alaska, Fairbanks (UAF)] [Institute of Arctic Biology (IAB), University of Alaska, Fairbanks (UAF); McGuire, A. David [University of Alaska] [University of Alaska; Barrett, K. [USGS Alaska Science Center] [USGS Alaska Science Center; Breen, Amy [International Arctic Research Center, SNAP, University of Alaska, Fairbanks (UAF)] [International Arctic Research Center, SNAP, University of Alaska, Fairbanks (UAF); Euskirchen, Eugenie S [University of Alaska] [University of Alaska; Johnstone, J. F. [University of Saskatchewan] [University of Saskatchewan; Kasischke, Eric S. [University of Maryland, College Park] [University of Maryland, College Park; Melvin, A. M. [University of Florida, Gainesville] [University of Florida, Gainesville; Bennett, A. [International Arctic Research Center, SNAP, University of Alaska, Fairbanks (UAF)] [International Arctic Research Center, SNAP, University of Alaska, Fairbanks (UAF); Mack, M. C. [University of Florida, Gainesville] [University of Florida, Gainesville; Rupp, Scott T. [International Arctic Research Center, SNAP, University of Alaska, Fairbanks (UAF)] [International Arctic Research Center, SNAP, University of Alaska, Fairbanks (UAF); Schuur, Edward [University of Florida] [University of Florida; Turetsky, M. R. [University of Guelph, Canada] [University of Guelph, Canada; Yuan, Fengming [ORNL] [ORNL

    2013-01-01

    There is a substantial amount of carbon stored in the permafrost soils of boreal forest ecosystems, where it is currently protected from decomposition. The surface organic horizons insulate the deeper soil from variations in atmospheric temperature. The removal of these insulating horizons through consumption by fire increases the vulnerability of permafrost to thaw, and the carbon stored in permafrost to decomposition. In this study we ask how warming and fire regime may influence spatial and temporal changes in active layer and carbon dynamics across a boreal forest landscape in interior Alaska. To address this question, we (1) developed and tested a predictive model of the effect of fire severity on soil organic horizons that depends on landscape-level conditions and (2) used this model to evaluate the long-term consequences of warming and changes in fire regime on active layer and soil carbon dynamics of black spruce forests across interior Alaska. The predictive model of fire severity, designed from the analysis of field observations, reproduces the effect of local topography (landform category, the slope angle and aspect and flow accumulation), weather conditions (drought index, soil moisture) and fire characteristics (day of year and size of the fire) on the reduction of the organic layercaused by fire. The integration of the fire severity model into an ecosystem process-based model allowed us to document the relative importance and interactions among local topography, fire regime and climate warming on active layer and soil carbon dynamics. Lowlands were more resistant to severe fires and climate warming, showing smaller increases in active layer thickness and soil carbon loss compared to drier flat uplands and slopes. In simulations that included the effects of both warming and fire at the regional scale, fire was primarily responsible for a reduction in organic layer thickness of 0.06 m on average by 2100 that led to an increase in active layer thickness of 1.1 m on average by 2100. The combination of warming and fire led to a simulated cumulative loss of 9.6 kgC m 2 on average by 2100. Our analysis suggests that ecosystem carbon storage in boreal forests in interior Alaska is particularly vulnerable, primarily due to the combustion of organic layer thickness in fire and the related increase in active layer thickness that exposes previously protected permafrost soil carbon to decomposition.

  8. In Situ Evaluation of Density, Viscosity and Thickness of Adsorbed Soft Layers by Combined Surface Acoustic Wave and Surface Plasmon Resonance

    E-Print Network [OSTI]

    L. Francis; J. -M. Friedt; C. Zhou; P. Bertrand

    2006-04-28

    We show the theoretical and experimental combination of acoustic and optical methods for the in situ quantitative evaluation of the density, the viscosity and the thickness of soft layers adsorbed on chemically tailored metal surfaces. For the highest sensitivity and an operation in liquids, a Love mode surface acoustic wave (SAW) sensor with a hydrophobized gold coated sensing area is the acoustic method, while surface plasmon resonance (SPR) on the same gold surface as the optical method is monitored simultaneously in a single set-up for the real-time and label-free measurement of the parameters of adsorbed soft layers, which means for layers with a predominant viscous behavior. A general mathematical modeling in equivalent viscoelastic transmission lines is presented to determine the correlation between experimental SAW signal shifts and the waveguide structure including the presence of the adsorbed layer and the supporting liquid from which it segregates. A methodology is presented to identify from SAW and SPR simulations the parameters representatives of the soft layer. During the absorption of a soft layer, thickness or viscosity changes are observed in the experimental ratio of the SAW signal attenuation to the SAW signal phase and are correlated with the theoretical model. As application example, the simulation method is applied to study the thermal behavior of physisorbed PNIPAAm, a polymer whose conformation is sensitive to temperature, under a cycling variation of temperature between 20 and 40 oC. Under the assumption of the bulk density and the bulk refractive index of PNIPAAm, thickness and viscosity of the film are obtained from simulations; the viscosity is correlated to the solvent content of the physisorbed layer.

  9. Boxy/peanut/X bulges, barlenses and the thick part of galactic bars: What are they and how did they form?

    E-Print Network [OSTI]

    Athanassoula, E

    2015-01-01

    Bars have a complex three-dimensional shape. In particular their inner part is vertically much thicker than the parts further out. Viewed edge-on, the thick part of the bar is what is commonly known as a boxy-, peanut- or X- bulge and viewed face-on it is referred to as a barlens. These components are due to disc and bar instabilities and are composed of disc material. I review here their formation, evolution and dynamics, using simulations, orbital structure theory and comparisons to observations.

  10. Reaction rate sensitivity of 44Ti production in massive stars and implications of a thick target yield measurement of 40Ca(alpha,gamma)44Ti

    SciTech Connect (OSTI)

    Hoffman, R D; Sheets, S A; Burke, J T; Scielzo, N D; Rauscher, T; Norman, E B; Tumey, S; Brown, T A; Grant, P G; Hurst, A M; Phair, L; Stoyer, M A; Wooddy, T; Fisker, J L; Bleuel, D

    2010-02-16

    We evaluate two dominant nuclear reaction rates and their uncertainties that affect {sup 44}Ti production in explosive nucleosynthesis. Experimentally we develop thick-target yields for the {sup 40}Ca({alpha},{gamma}){sup 44}Ti reaction at E{sub {alpha}} = 4.13, 4.54, and 5.36 MeV using {gamma}-ray spectroscopy. At the highest beam energy, we also performed an activation measurement which agrees with the thick target result. From the measured yields a stellar reaction rate was developed that is smaller than current statistical-model calculations and recent experimental results, which would suggest lower {sup 44}Ti production in scenarios for the {alpha}-rich freeze out. Special attention has been paid to assessing realistic uncertainties of stellar reaction rates produced from a combination of experimental and theoretical cross sections. With such methods, we also develop a re-evaluation of the {sup 44}Ti({alpha},p){sup 47}V reaction rate. Using these two rates we carry out a sensitivity survey of {sup 44}Ti synthesis in eight expansions representing peak temperature and density conditions drawn from a suite of recent supernova explosion models. Our results suggest that the current uncertainty in these two reaction rates could lead to as large an uncertainty in {sup 44}Ti synthesis as that produced by different treatments of stellar physics.

  11. 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.

  12. 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.

  13. Demonstrating 1 nm-oxide-equivalent-thickness HfO{sub 2}/InSb structure with unpinning Fermi level and low gate leakage current density

    SciTech Connect (OSTI)

    Trinh, Hai-Dang [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China) [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Lin, Yueh-Chin; Nguyen, Hong-Quan; Luc, Quang-Ho [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China)] [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Nguyen, Minh-Thuy; Duong, Quoc-Van; Nguyen, Manh-Nghia [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam)] [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Wang, Shin-Yuan [Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China)] [Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China); Yi Chang, Edward [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China) [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China)

    2013-09-30

    In this work, the band alignment, interface, and electrical characteristics of HfO{sub 2}/InSb metal-oxide-semiconductor structure have been investigated. By using x-ray photoelectron spectroscopy analysis, the conduction band offset of 1.78 ± 0.1 eV and valence band offset of 3.35 ± 0.1 eV have been extracted. The transmission electron microscopy analysis has shown that HfO{sub 2} layer would be a good diffusion barrier for InSb. As a result, 1 nm equivalent-oxide-thickness in the 4 nm HfO{sub 2}/InSb structure has been demonstrated with unpinning Fermi level and low leakage current of 10{sup ?4} A/cm{sup ?2}. The D{sub it} value of smaller than 10{sup 12} eV{sup ?1}cm{sup ?2} has been obtained using conduction method.

  14. Structural, magnetic, and mechanical properties of 5 {mu}m thick SmCo films suitable for use in microelectromechanical systems

    SciTech Connect (OSTI)

    Walther, A. [Institut Neel, CNRS-UJF, 25 rue des Martyrs, 38042 Grenoble (France); CEA Leti-MINATEC, 17 rue des Martyrs, 38054 Grenoble (France); Givord, D.; Dempsey, N. M. [Institut Neel, CNRS-UJF, 25 rue des Martyrs, 38042 Grenoble (France); Khlopkov, K.; Gutfleisch, O. [IFW Dresden, Institute of Metallic Materials, Helmholtzstr. 20, 01069 Dresden (Germany)

    2008-02-15

    5 {mu}m thick SmCo films were deposited onto Si substrates using triode sputtering. A study of the influence of deposition temperature (T{sub dep}{<=}600 deg. C) on the structural, magnetic, and mechanical properties has shown that optimum properties [highest degree of in-plane texture, maximum in-plane coercivity and remanence (1.3 and 0.8 T, respectively), and no film peel-off] are achieved for films deposited at the relatively low temperature of 350 deg. C. This temperature is compatible with film integration into microelectromechanical systems. The deposition rate was increased from 3.6 to 18 {mu}m/h by increasing the surface area of the target from 7 to 81 cm{sup 2} while keeping the target potential fixed. Mechanically intact films could be prepared by deposition onto prepatterned films or deposition through a mask.

  15. 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. (Hillsborough, NJ)

    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.

  16. 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.

  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. Tin oxide thick film by doping rare earth for detecting traces of CO{sub 2}: Operating in oxygen-free atmosphere

    SciTech Connect (OSTI)

    Xiong, Ya; Zhang, Guozhu; Zhang, Shunping; Zeng, Dawen; Xie, Changsheng, E-mail: csxie@mail.hust.edu.cn

    2014-04-01

    Highlights: • La, Gd, and Lu doped SnO{sub 2} with their sensing properties toward CO{sub 2} were compared. • The microstructures of SnO{sub 2}-based nanoparticles were elaborately characterized. • La-SnO{sub 2} thick film shows superior response toward trace ppm CO{sub 2}. • Our sensing material can be recommended to employ in oxygen-free environment. - Abstract: SnO{sub 2} thick films doped with atomic ratios ranging from 0 up to 8 at.% La, 8 at.% Gd, 8 at.% Lu were fabricated, respectively, via hydrothermal and impregnation methods. The crystal phase, morphology, and chemical composition of the SnO{sub 2}-based nanoparticles were characterized by XRD, FE-SEM, EDX, HRTEM and XPS. Sensing properties of La-SnO{sub 2}, Gd-SnO{sub 2}, Lu-SnO{sub 2} films, as well as the pure SnO{sub 2} film, were analyzed toward CO{sub 2} in the absence of O{sub 2}. It was found that the optimal doping element was La and the best doping ratio was 4 at.%. The maximum response appeared at an operating temperature of 250 °C, on which condition the 4 at.% La-SnO{sub 2} exhibited a remarkable improvement of response from 5.12 to 29.8 when increasing CO{sub 2} concentration from 50 to 500 ppm. Furthermore, the working mechanism underlying such enhancement in CO{sub 2}-sensing functions by La additive in the absence of O{sub 2} was proposed and discussed.

  19. Leachability of Cu and Ni in wood ash-amended soil as impacted by humic and fulvic acid

    E-Print Network [OSTI]

    Ma, Lena

    , and shavings in boilers to produce energy at paper mills, plywood plants, and other electrical generating

  20. Mask Roughness Induced LER in EUV Lithography

    E-Print Network [OSTI]

    McClinton, Brittany

    2011-01-01

    focus…………………………………… Alt-PSM……………………………………………………………… 5.2.122-nm……………………….. 5.2.2 Alt-PSM vs. Lines and Spaces at 22-Simplified LER, alt-psm……………………………… Simulated LER, 22nm alt-