Sample records for thick plywood roughly

  1. ROUGH THIN PAVEMENT THICKNESS ESTIMATION BY GPR N. Pinel, L. Liu, C. Bourlier, Y. Wang

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ROUGH THIN PAVEMENT THICKNESS ESTIMATION BY GPR N. Pinel, L. Liu, C. Bourlier, Y. Wang IREENA pavements consider flat interfaces for simpli- fication. In this paper, the roughness of the surfaces is taken into account. First, the amplitudes of the first two echoes from the rough thin pavement

  2. Graphene thickness dependent adhesion force and its correlation to surface roughness

    SciTech Connect (OSTI)

    Pourzand, Hoorad [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Tabib-Azar, Massood, E-mail: azar.m@utah.edu [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Biomedical Engineering, University of Utah, Salt Lake City, Utah 84112 (United States)

    2014-04-28T23:59:59.000Z

    In this paper, adhesion force of graphene layers on 300?nm silicon oxide is studied. A simple model for measuring adhesion force for a flat surface with sub-nanometer roughness was developed and is shown that small surface roughness decreases adhesion force while large roughness results in an effectively larger adhesion forces. We also show that surface roughness over scales comparable to the tip radius increase by nearly a factor of two, the effective adhesion force measured by the atomic force microscopy. Thus, we demonstrate that surface roughness is an important parameter that should be taken into account in analyzing the adhesion force measurement results.

  3. Economic impact of log grade on the production of plywood and lumber

    E-Print Network [OSTI]

    Ledford, Donald Wayne

    1986-01-01T23:59:59.000Z

    and lumber. Product recovery studies were conducted for a band headsaw, a chip-n-saw, a chip-n-saw stud mill, a plywood mill peeling I/8" veneer, and a plywood mill peeling I/6" veneer. The relationship of volume and grade of product recovery... samples at the stud mill, expressed in percent of total lumber production from the log sample 66 18. Log samples peeled to 1/8" veneer with recoveries of dry veneer 69 Plywood production (1/8" veneer) per ton of log input 71 19b Plywood production...

  4. The impact of sheared vs. sawn timber in the typical southern pine plywood mill

    E-Print Network [OSTI]

    Swinney, Russell Garrett

    1989-01-01T23:59:59.000Z

    . Areas of impact from sheared logs within the plywood manufacturing process. 20 5. BP grade veneer peeled from the butt end of a sawn log 25 6. BP grade veneer peeled from the butt end of a sheared log. 26 7. Visible defects in veneer resulting from... two block log is trimmed four to six inches to eliminate obvious shear damage, then the log will be too short to get two 103-inch blocks. The result is that one block will be chipped for sale to a pulp mill rather than peeled for veneer for use...

  5. Controlling rough paths

    E-Print Network [OSTI]

    2013-03-05T23:59:59.000Z

    original work of Lyons [7] roughness is measured in p-variation norm, instead here we prefer to .... e.g. for cochains A; B of degree 1 and 2 respectively, we have.

  6. Drying Rough Rice in Storage.

    E-Print Network [OSTI]

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

    1960-01-01T23:59:59.000Z

    Drying. Rough Rice in Storage Ih AGRf""' TURP YPERIMENT STAT10 I. TEXAS SUMMARY Research was conducted at the Rice-Pasture Experiment Station near Beaumont during 7 crop years (1952-53 through 1958-59) to determine the engineering problems... and the practicability of dry- ing rough rice in storage in Texas. Drying rice in storage means drying rice in the same bin in which it is to be stored. Rough rice, with initial moisture contents of 15.0 to 23.0 percent, was dried at depths of 4 to 10 feet...

  7. Pavement Thickness Design Parameter

    E-Print Network [OSTI]

    Pavement Thickness Design Parameter Impacts 2012 Municipal Streets Seminar November 14, 2012 Paul D. Wiegand, P.E. #12;Pavement Thickness Design · How do cities decide how thick to build their pavements;Pavement Thickness Design · Correct answer ­ A data-based analysis! · Doesn't have to be difficult and time

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

    E-Print Network [OSTI]

    Xie, Yu

    2007-09-17T23:59:59.000Z

    on the retrieval of ice cloud effective particle size, optical thickness and cloud-top temperature. Three particle surface conditions, smooth, moderately rough and deeply rough, are considered in the visible and near-infrared channels (0.65 and 3.75 Ã...

  9. Electrokinetic transport in microchannels with random roughness

    SciTech Connect (OSTI)

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

    2008-01-01T23:59:59.000Z

    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.

  10. 1216 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 5, MAY 2009 Wave Propagation in a Randomly Rough

    E-Print Network [OSTI]

    Tsang, Leung

    and the power loss. The derived result is expressed in terms of a double Sommerfeld integral. The double propagation and power loss are illustrated as a function of roughness characteristics and waveguide thickness thickness, the waveguide model shows signif- icantly different power loss as compared to the plane

  11. Thick film hydrogen sensor

    DOE Patents [OSTI]

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

    1995-01-01T23:59:59.000Z

    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.

  12. Friction of a slider on a granular layer: Nonmonotonic thickness dependence and effect of boundary conditions

    E-Print Network [OSTI]

    Kudrolli, Arshad

    Friction of a slider on a granular layer: Nonmonotonic thickness dependence and effect of boundary the effective friction encountered by a mass sliding on a granular layer as a function of bed thickness and boundary roughness conditions. The observed friction has minima for a small number of layers before

  13. Water Dynamics at Rough Interfaces

    E-Print Network [OSTI]

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

    2014-07-21T23:59:59.000Z

    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.

  14. Enhanced thermoelectric performance of rough silicon nanowires

    E-Print Network [OSTI]

    Yang, Peidong

    LETTERS Enhanced thermoelectric performance of rough silicon nanowires Allon I. Hochbaum1 *, Renkun, such that roughly 15 terawatts of heat is lost to the environment. Thermoelectric modules could potentially convert part of this low-grade waste heat to electricity. Their efficiency depends on the thermoelectric figure

  15. Simplified models for mask roughness induced LER

    SciTech Connect (OSTI)

    McClinton, Brittany; Naulleau, Patrick

    2011-02-21T23:59:59.000Z

    The ITRS requires < 1.2nm line-edge roughness (LER) for the 22nm half-pitch node. Currently, we can consistently achieve only about 3nm LER. Further progress requires understanding the principle causes of LER. Much work has already been done on how both the resist and LER on the mask effect the final printed LER. What is poorly understood, however, is the extent to which system-level effects such as mask surface roughness, illumination conditions, and defocus couple to speckle at the image plane, and factor into LER limits. Presently, mask-roughness induced LER is studied via full 2D aerial image modeling and subsequent analysis of the resulting image. This method is time consuming and cumbersome. It is, therefore, the goal of this research to develop a useful 'rule-of-thumb' analytic model for mask roughness induced LER to expedite learning and understanding.

  16. Computer Simulation of Uranyl Uptake by the Rough Lipopolysaccharide...

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

    Computer Simulation of Uranyl Uptake by the Rough Lipopolysaccharide Membrane of Pseudomonas aeruginosa. Computer Simulation of Uranyl Uptake by the Rough Lipopolysaccharide...

  17. Critical thickness in silicone thermosets

    E-Print Network [OSTI]

    Deopura, Manish, 1975-

    2005-01-01T23:59:59.000Z

    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 ...

  18. Viscoelastic contact mechanics between randomly rough surfaces

    E-Print Network [OSTI]

    Michele Scaraggi; Bo N. J. Persson

    2014-06-27T23:59:59.000Z

    We present exact numerical results for the friction force and the contact area for a viscoelastic solid (rubber) in sliding contact with hard, randomly rough substrates. The rough surfaces are self-affine fractal with roughness over several decades in length scales. We calculate the contribution to the friction from the pulsating deformations induced by the substrate asperities. We also calculate how the area of real contact, $A(v,p) $, depends on the sliding speed $v$ and on the nominal contact pressure $p$, and we show how the contact area for any sliding speed can be obtained from a universal master curve $A(p)$. The numerical results are found to be in good agreement with the predictions of an analytical contact mechanics theory.

  19. ROUGHNESS LENGTHS FOR THE SAVANNAH RIVER SITE

    SciTech Connect (OSTI)

    Hunter, C.

    2012-03-28T23:59:59.000Z

    Surface roughness values for the areas surrounding the H, D and N-Area meteorological towers were computed from archived 2010 meteorological data. These 15-minute-averaged data were measured with cup anemometers and bidirectional wind vanes (bivanes) 61 m above the surface. The results of the roughness calculation using the standard deviation of elevation angle {sigma}{sub E}, and applying the simple formula based on tree canopy height, gave consistent estimates for roughness around the H-Area tower in the range of 1.76 to 1.86 m (95% confidence interval) with a mean value of 1.81 m. Application of the {sigma}{sub E} method for the 61-m level at D and N-Areas gave mean values of 1.71 and 1.81 with confidence ranges of 1.62-1.81 and 1.73-1.88 meters, respectively. Roughness results are azimuth dependent, and thus are presented as averages over compass sectors spanning 22.5 degrees. Calculated values were compared to other methods of determining roughness, including the standard deviation of the azimuth direction, {sigma}{sub A}, and standard deviation of the wind speed, {sigma}{sub U}. Additional data was obtained from a sonic anemometer at 61-m on the H-Area tower during a period of a few weeks in 2010. Results from the sonic anemometer support our use of {sigma}{sub E} to calculate roughness. Based on the H-Area tower results, a surface roughness of 1.8 m using is recommended for use in dispersion modeling applications that consider the impacts of a contaminant release to individuals along the Site boundary. The canopy surrounding the H-Area tower is relatively uniform (i.e., little variance in roughness by upwind direction), and data supplied by the U.S. Forest Service at Savannah River show that the canopy height and composition surrounding the H-Area tower is reasonably representative of forested areas throughout the SRS reservation. For dispersion modeling analyses requiring assessments of a co-located worker within the respective operations area, recommended area-specific values range from 0.3 m for E Area to 0.7 m for A Area at the Savannah River National Laboratory. These area-specific values, summarized in Table 4-1, were determined using the Environmental Protection Agency's AERSURFACE computer algorithm.

  20. Influence of surface roughness on superhydrophobicity

    E-Print Network [OSTI]

    C. Yang; U. Tartaglino; B. N. J. Persson

    2006-09-30T23:59:59.000Z

    Superhydrophobic surfaces, with liquid contact angle theta greater than 150 degree, have important practical applications ranging from self-cleaning window glasses, paints, and fabrics to low-friction surfaces. Many biological surfaces, such as the lotus leaf, have hierarchically structured surface roughness which is optimized for superhydrophobicity through natural selection. Here we present a molecular dynamics study of liquid droplets in contact with self-affine fractal surfaces. Our results indicate that the contact angle for nanodroplets depends strongly on the root-mean-square surface roughness amplitude but is nearly independent of the fractal dimension D_f of the surface.

  1. A Rough Logic Formalism for Fuzzy Controllers

    E-Print Network [OSTI]

    Lin, Tsau Young

    logic. 1. Introduction In complex systems, such as power systems, control sub­systems are the most of transformations of mathematical models. It starts with a symbolic model that describes the control system in termsA Rough Logic Formalism for Fuzzy Controllers: A Hard and Soft Computing View T.Y. Lin Department

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

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

    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...

  3. Laser detection of material thickness

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM)

    2002-01-01T23:59:59.000Z

    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.

  4. Speed Map for Autonomous Rovers over Rough Terrain

    E-Print Network [OSTI]

    Loh, Jonathan Edau

    2012-01-01T23:59:59.000Z

    Grid Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . .considered obstacles [27] Grid Map showing Tile Size, Cellspeed map. It also covers grid maps and terrain roughness,

  5. Equivalent roughness height for plane bed under oscillatory flow

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , the bed roughness height of a flat and fixed bed is given in terms of the Nikuradse roughness height (ks may be several orders of magnitude larger than for a fixed bed. This is probably causedEquivalent roughness height for plane bed under oscillatory flow Beno^it Camenen , Magnus Larson

  6. The role of an interface on Ni film removal and surface roughness after irradiation by femtosecond laser pulses

    SciTech Connect (OSTI)

    Murphy, Ryan D. [Applied Physics Program, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Applied Physics Program, University of Michigan, Ann Arbor, Michigan 48109 (United States); Torralva, Ben [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Yalisove, Steven M. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2013-05-06T23:59:59.000Z

    We have observed thin film removal from glass substrates after the irradiation of Ni films with femtosecond laser pulses in air. It was found that the material removal threshold and laser-induced morphology are dependent on film thickness. With decreasing thickness, material removal transitions from intra-film separation to removal at the Ni-glass interface. The Gaussian energy distribution of the laser pulse allows for intra-film separation in the annular region of the crater and interface separation in the center. We propose a model to explain these data as well as the observed increased surface roughness in the interfacial removal regions.

  7. 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)

    1990-01-01T23:59:59.000Z

    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.

  8. Extreme ultraviolet mask substrate surface roughness effects on lithography patterning

    SciTech Connect (OSTI)

    George, Simi; Naulleau, Patrick; Salmassi, Farhad; Mochi, Iacopo; Gullikson, Eric; Goldberg, Kenneth; Anderson, Erik

    2010-06-21T23:59:59.000Z

    In extreme ultraviolet lithography exposure systems, mask substrate roughness induced scatter contributes to LER at the image plane. In this paper, the impact of mask substrate roughness on image plane speckle is explicitly evaluated. A programmed roughness mask was used to study the correlation between mask roughness metrics and wafer plane aerial image inspection. We find that the roughness measurements by top surface topography profile do not provide complete information on the scatter related speckle that leads to LER at the image plane. We suggest at wavelength characterization by imaging and/or scatter measurements into different frequencies as an alternative for a more comprehensive metrology of the mask substrate/multilayer roughness effects.

  9. High Temperature Superconducting Thick Films

    DOE Patents [OSTI]

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

    2005-08-23T23:59:59.000Z

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

  10. Equivalent Roughness Height for Plane Bed under Steady Flow

    E-Print Network [OSTI]

    US Army Corps of Engineers

    current conditions. In general, owing to dimensional reasons, the bed roughness height of a flat and fixed orders of magnitude larger than for a fixed bed. This is probably caused by the increased energyEquivalent Roughness Height for Plane Bed under Steady Flow Benoît Camenen, Ph.D.1 ; Atilla Bayram

  11. FRACTAL DESCRIPTION OF ROUGH SURFACES FOR HAPTIC DISPLAY

    E-Print Network [OSTI]

    Stanford University

    FRACTAL DESCRIPTION OF ROUGH SURFACES FOR HAPTIC DISPLAY A DISSERTATION SUBMITTED TO THE DEPARTMENT system using fractals. A background on traditional methods for describing surface roughness is given. Fractals are used to characterize one- dimensional surface profiles using two parameters, the amplitude

  12. Rough-Fuzzy MLP: Modular Evolution, Rule Generation, and Evaluation

    E-Print Network [OSTI]

    Mitra, Sushmita

    efficient systems in soft computing paradigm. Recently, the theory of rough sets [2], [3] has emerged, Sushmita Mitra, Senior Member, IEEE, and Pabitra Mitra, Student Member, IEEE Abstract--A methodology Terms--Soft computing, knowledge-based fuzzy networks, rough sets, genetic algorithms, pattern

  13. ORIGINAL PAPER Transient Heat Conduction Between Rough Sliding Surfaces

    E-Print Network [OSTI]

    Barber, James R.

    ORIGINAL PAPER Transient Heat Conduction Between Rough Sliding Surfaces Yuwei Liu · J. R. Barber+Business Media New York 2014 Abstract When two rough bodies slide against each other, asperities on the opposing contact pressure as functions of the separation between reference planes in the two surfaces. We find

  14. Distributed Roughness Receptivity in a Flat Plate Boundary Layer

    E-Print Network [OSTI]

    Kuester, Matthew Scott

    2014-04-18T23:59:59.000Z

    for the three different unit Reynolds num- ber test conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.4 Spanwise uniformity of boundary layer integral quantities at x = 870 mm for low unit Reynolds number test condition... with the distributed roughness configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3.5 Differential pressure across the flat plate leading edge. . . . . . . . . . 25 3.6 Roughness patch (k = 1 mm), before windowing . . . . . . . . . . . . 27 3...

  15. Fuzzy Rough Positive Region based Nearest Neighbour Classification

    E-Print Network [OSTI]

    Gent, Universiteit

    of the main subjects in machine learning and pattern recognition, with applications in fields like spam theory to improve the FNN classifier. Fuzzy rough set theory was designed to model imperfect knowledgeFuzzy Rough Positive Region based Nearest Neighbour Classification Nele Verbiest, Chris Cornelis

  16. Case Generation Using Rough Sets with Fuzzy Representation

    E-Print Network [OSTI]

    Mitra, Pabitra

    , granular computing, rough-fuzzy hybridization, soft computing, pattern recognition, data mining. æ 1 for case generation. Fuzzy set theory is used for linguistic representation of patterns, thereby producing a fuzzy granulation of the feature space. Rough set theory is used to obtain dependency rules which model

  17. Measurement of normal contact stiffness of fractal rough surfaces

    E-Print Network [OSTI]

    Chongpu Zhai; Sébastien Bevand; Yixiang Gan; Dorian Hanaor; Gwénaëlle Proust; Bruno Guelorget; Delphine Retraint

    2014-09-03T23:59:59.000Z

    We investigate the effects of roughness and fractality on the normal contact stiffness of rough surfaces. Samples of isotropically roughened aluminium surfaces are considered. The roughness and fractal dimension were altered through blasting using different sized particles. Subsequently, surface mechanical attrition treatment (SMAT) was applied to the surfaces in order to modify the surface at the microscale. The surface topology was characterised by interferometry based profilometry. The normal contact stiffness was measured through nanoindentation with a flat tip utilising the partial unloading method. We focus on establishing the relationships between surface stiffness and roughness, combined with the effects of fractal dimension. The experimental results, for a wide range of surfaces, showed that the measured contact stiffness depended very closely on surfaces' root mean squared (RMS) slope and their fractal dimension, with correlation coefficients of around 90\\%, whilst a relatively weak correlation coefficient of 57\\% was found between the contact stiffness and RMS roughness.

  18. Tailoring interlayer coupling and coercivity in Co/Mn/Co trilayers by controlling the interface roughness

    SciTech Connect (OSTI)

    Zhang, Bin; Wu, Chii-Bin; Kuch, Wolfgang, E-mail: kuch@physik.fu-berlin.de [Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin (Germany)

    2014-06-21T23:59:59.000Z

    Epitaxial Co/Mn/Co trilayers with a wedged Mn layer were grown on Cu(001) and studied by magneto-optical Kerr effect measurements. The bottom Co film as well as the Mn film exhibits a layer-by-layer growth mode, which allows to modify both interface roughnesses on the atomic scale by tuning the thicknesses of the films to achieve a certain filling of their topmost atomic layers. The onset of antiferromagnetic order in the Mn layer at room temperature was found at thicknesses of 4.1 (4.8) and 3.4 (4.0) atomic monolayers (ML) for a filled (half-filled) topmost atomic layer of the bottom Co film in Mn/Co bilayers and Co/Mn/Co trilayers, respectively. Magnetization loops with only one step were found for a trilayer with half-filled topmost atomic layer of the bottom Co film, while loops with two separate steps have been observed in trilayers with an integer number of atomic layers in the bottom Co film. The coercivity of the top Co film shows an oscillation with 1 ML period as a function of the Mn thickness above 10 ML, which is interpreted as the influence of the atomic-scale control of the interface roughness on the interface exchange coupling between the antiferromagnetic Mn and the top ferromagnetic (FM) Co layer. The strength of the magnetic interlayer coupling between the top and bottom Co layers through the Mn layer for an integer number of atomic layers in the bottom Co layer, deduced from minor-loop measurements, exhibits an oscillation with a period of 2 ML Mn thickness, indicative of direct exchange coupling through the antiferromagnetic Mn layer. In addition, a long-period interlayer coupling of the two FM layers with antiparallel coupling maxima at Mn thicknesses of 2.5, 8.2, and 13.7 ML is observed and attributed to indirect exchange coupling of the Rudermann-Kittel-Kasuya-Yosida type.

  19. Surface forces: Surface roughness in theory and experiment

    SciTech Connect (OSTI)

    Parsons, Drew F., E-mail: Drew.Parsons@anu.edu.au; Walsh, Rick B.; Craig, Vincent S. J. [Department of Applied Mathematics, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200 (Australia)] [Department of Applied Mathematics, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2014-04-28T23:59:59.000Z

    A method of incorporating surface roughness into theoretical calculations of surface forces is presented. The model contains two chief elements. First, surface roughness is represented as a probability distribution of surface heights around an average surface height. A roughness-averaged force is determined by taking an average of the classic flat-surface force, weighing all possible separation distances against the probability distributions of surface heights. Second the model adds a repulsive contact force due to the elastic contact of asperities. We derive a simple analytic expression for the contact force. The general impact of roughness is to amplify the long range behaviour of noncontact (DLVO) forces. The impact of the elastic contact force is to provide a repulsive wall which is felt at a separation between surfaces that scales with the root-mean-square (RMS) roughness of the surfaces. The model therefore provides a means of distinguishing between “true zero,” where the separation between the average centres of each surface is zero, and “apparent zero,” defined by the onset of the repulsive contact wall. A normal distribution may be assumed for the surface probability distribution, characterised by the RMS roughness measured by atomic force microscopy (AFM). Alternatively the probability distribution may be defined by the histogram of heights measured by AFM. Both methods of treating surface roughness are compared against the classic smooth surface calculation and experimental AFM measurement.

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

    SciTech Connect (OSTI)

    Fluteau, T.; Bessis, C.; Barraud, C., E-mail: clement.barraud@univ-paris-diderot.fr; Della Rocca, M. L.; Lafarge, P. [Université Paris Diderot, Sorbonne Paris Cité, MPQ, UMR 7162, CNRS, 75205 Paris Cedex 13 (France); Martin, P.; Lacroix, J.-C. [Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086, CNRS, 15 rue J.-A. de Baïf, 75205 Paris Cedex 13 (France)

    2014-09-21T23:59:59.000Z

    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.

  1. Effect of Surface Roughness on Wind Turbine Performance

    E-Print Network [OSTI]

    Ehrmann, Robert Schaefer

    2014-06-25T23:59:59.000Z

    40% for 140 µm roughness, corresponding to a 2.3% loss in annual energy production. Simulated performance loss compares well to measured performance loss on an in-service wind turbine....

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

    E-Print Network [OSTI]

    Yovanovich, M. Michael

    1967-01-01T23:59:59.000Z

    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 ...

  3. Hypersonic Measurements of Roughness-Induced Transient Growth

    E-Print Network [OSTI]

    Sharp, Nicole Susanne

    2014-04-17T23:59:59.000Z

    but about boundary-layer stability in general. Dr. Rob Downs and Doug Kutz provided valuable assistance and code when I was designing my quasi-random periodic distributed roughness. Jason Monschke’s help has been invaluable, not only for the self- similar... simulations using the periodically-spaced discrete roughness geometry. Jason Monschke has performed the optimal disturbance calculations described in the dissertation using code kindly shared by Dr. Simone Zuccher. Jason is also working on secondary...

  4. The thermal Casimir effect for rough metallic plates

    E-Print Network [OSTI]

    G. Bimonte

    2007-11-04T23:59:59.000Z

    We propose a new theory of thermal Casimir effect, holding for the experimentally important case of metallic surfaces with a roughness having a spatial scale smaller than the skin depth. The theory is based on a simple phenomenological model for a rough conductor, that explicitly takes account of the fact that ohmic conduction in the immediate vicinity of the surface of a conductor is much impeded by surface roughness, if the amplitude of roughness is smaller than the skin depth. As a result of the new model, we find that surface roughness strongly influences the magnitude of the thermal correction to the Casimir force, independently of the plates separation. Our model, while consistent with recent accurate measurements of the Casimir force in the submicron range, leads to a new prediction for the not yet observed thermal correction to the Casimir force at large plates separation. Besides the thermal Casimir problem, our model is relevant for the correct theoretical interpretation of current experiments probing other proximity effects between conductors, like radiative heat transfer and quantum friction.

  5. Structural contribution to the roughness of supersmooth crystal surface

    SciTech Connect (OSTI)

    Butashin, A. V.; Muslimov, A. E., E-mail: amuslimov@mail.ru; Kanevsky, V. M.; Deryabin, A. N.; Pavlov, V. A.; Asadchikov, V. E. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2013-05-15T23:59:59.000Z

    Technological advances in processing crystals (Si, sapphire {alpha}-Al{sub 2}O{sub 3}, SiC, GaN, LiNbO{sub 3}, SrTiO{sub 3}, etc.) of substrate materials and X-ray optics elements make it possible to obtain supersmooth surfaces with a periodicity characteristic of the crystal structure. These periodic structures are formed by atomically smooth terraces and steps of nano- and subnanometer sizes, respectively. A model surface with such nanostructures is proposed, and the relations between its roughness parameters and the height of atomic steps are determined. The roughness parameters calculated from these relations almost coincide with the experimental atomic force microscopy (AFM) data obtained from 1 Multiplication-Sign 1 and 10 Multiplication-Sign 10 {mu}m areas on the surface of sapphire plates with steps. The minimum roughness parameters for vicinal crystal surfaces, which are due to the structural contribution, are calculated based on the approach proposed. A comparative analysis of the relief and roughness parameters of sapphire plate surfaces with different degrees of polishing is performed. A size effect is established: the relief height distribution changes from stochastic to regular with a decrease in the surface roughness.

  6. Friction of a slider on a granular layer: Non-monotonic thickness dependence and effect of boundary conditions

    E-Print Network [OSTI]

    Saloome Siavoshi; Ashish V. Orpe; Arshad Kudrolli

    2005-12-22T23:59:59.000Z

    We investigate the effective friction encountered by a mass sliding on a granular layer as a function of bed thickness and boundary roughness conditions. The observed friction has minima for a small number of layers before it increases and saturates to a value which depends on the roughness of the sliding surface. We use an index-matched interstitial liquid to probe the internal motion of the grains with fluorescence imaging in a regime where the liquid has no significant effect on the measured friction. The shear profiles obtained as a function of depth show decrease in slip near the sliding surface as the layer thickness is increased. We propose that the friction depends on the degree of grain confinement relative to the sliding surfaces.

  7. Inhomogeneous Cooling of the Rough Granular Gas in Two Dimensions

    E-Print Network [OSTI]

    Sudhir N. Pathak; Dibyendu Das; R. Rajesh

    2014-07-03T23:59:59.000Z

    We study the inhomogeneous clustered regime of a freely cooling granular gas of rough particles in two dimensions using large-scale event driven simulations and scaling arguments. During collisions, rough particles dissipate energy in both the normal and tangential directions of collision. In the inhomogeneous regime, translational kinetic energy and the rotational energy decay with time $t$ as power-laws $t^{-\\theta_T}$ and $t^{-\\theta_R}$. We numerically determine $\\theta_T \\approx 1$ and $\\theta_R \\approx 1.6$, independent of the coefficients of restitution. The inhomogeneous regime of the granular gas has been argued to be describable by the ballistic aggregation problem, where particles coalesce on contact. Using scaling arguments, we predict $\\theta_T=1$ and $\\theta_R=1$ for ballistic aggregation, $\\theta_R$ being different from that obtained for the rough granular gas. Simulations of ballistic aggregation with rotational degrees of freedom are consistent with these exponents.

  8. Journal of Differential Equations Ramification of rough paths

    E-Print Network [OSTI]

    2013-03-05T23:59:59.000Z

    Dec 1, 2009 ... B-series. The stack of iterated integrals of a path is embedded in a larger al- gebraic structure ... iterated integrals [18,19] which is at the base of Lyons theory of rough paths [20]. Lyons theory ...... ?|b| ? g(|b|)(rs), see e.g. [5, p.

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

    E-Print Network [OSTI]

    2013-03-05T23:59:59.000Z

    fractional Brownian motion B with any Hurst parameter H ? (0,1), by means ... Rough paths analysis is a theory introduced by Terry Lyons in the pioneering ... functions with finite p-variation with p > 1, or by Hölder continuous functions of order ...

  10. Technical Briefs A Compact Model for Spherical Rough

    E-Print Network [OSTI]

    Bahrami, Majid

    of rough spheres includes two problems, i the bulk compression and ii deformation of asperities. Different index as a criterion for plastic flow of mi- crocontacts. They reported that the load has little effect on the deformation regime. Based on the plasticity index, they concluded that except for especially smooth surfaces

  11. Studies of the 3D surface roughness height

    SciTech Connect (OSTI)

    Avisane, Anita; Rudzitis, Janis; Kumermanis, Maris [Institute of Mechanical Engineering, Riga Technical University, Ezermalas str. 6k, Riga (Latvia)

    2013-12-16T23:59:59.000Z

    Nowadays nano-coatings occupy more and more significant place in technology. Innovative, functional coatings acquire new aspects from the point of view of modern technologies, considering the aggregate of physical properties that can be achieved manipulating in the production process with the properties of coatings’ surfaces on micro- and nano-level. Nano-coatings are applied on machine parts, friction surfaces, contacting parts, corrosion surfaces, transparent conducting films (TCF), etc. The equipment available at present for the production of transparent conducting oxide (TCO) coatings with highest quality is based on expensive indium tin oxide (ITO) material; therefore cheaper alternatives are being searched for. One such offered alternative is zink oxide (ZnO) nano-coatings. Evaluating the TCF physical and mechanical properties and in view of the new ISO standard (EN ISO 25178) on the introduction of surface texture (3D surface roughness) in the engineering calculations, it is necessary to examine the height of 3D surface roughness, which is one of the most significant roughness parameters. The given paper studies the average values of 3D surface roughness height and the most often applied distribution laws are as follows: the normal distribution and Rayleigh distribution. The 3D surface is simulated by a normal random field.

  12. Large deviations for rough paths of fractional Brownian motion

    E-Print Network [OSTI]

    Millet, Annie

    limit theorem. Stochastic modeling deals basically with rough path controls. Indeed, the ground-breaking It^o's theory on stochastic differential equations is based on Brownian motion, which has almost surely nowhere differentiable sam- ple paths but only -H¨older continuous ones, with ]0, 1 2 [. Note

  13. Hypersonic Measurements of Roughness-Induced Transient Growth 

    E-Print Network [OSTI]

    Sharp, Nicole Susanne

    2014-04-17T23:59:59.000Z

    streaks may play a key role in roughness-induced transition but has not previously been deliberately observed in hypersonic flow. To make such measurements, the present work studies the boundary layer of a 5° half-angle smooth cone paired with a slightly...

  14. Discussion of ``Atmospheric Momentum Roughness Applied to Stage-Discharge

    E-Print Network [OSTI]

    the Darcy-Weisbach equation and conventional log law and derive an alternative log law equation to calculate discussion. Concerning the resistance equations, if their Eq. 2 holds, the Darcy-Weisbach friction factor f equation and the selection of appropriate roughness param- eters. They discuss the merits of different

  15. Calculating Very Rough Market Share Using the Canadian Business Database

    E-Print Network [OSTI]

    Thompson, Michael

    Calculating Very Rough Market Share Using the Canadian Business Database If you cannot find market market share using the company information provided in the Canadian Business Database (CBD), an online - it should be considered a last resort for this information. STEP 1: ACCESS THE CANADIAN BUSINESS DATABASE 1a

  16. The effect of roughness on aerosol deposition in tubes

    E-Print Network [OSTI]

    Chavez, Mario Cesar

    1997-01-01T23:59:59.000Z

    Experimental measurements of simulated roughness within tubes and the subsequent aerosol penetration performance through these tubes were conducted for a aerosol particle size range of 5 nm to 20 nm and a flow rate range of 28 L/min to 169.9 L...

  17. BAYESIAN METHOD FOR SEGMENTATION OF SAR IMAGES IN ROUGH TERRAIN

    E-Print Network [OSTI]

    Oldenburg, Carl von Ossietzky Universität

    BAYESIAN METHOD FOR SEGMENTATION OF SAR IMAGES IN ROUGH TERRAIN Marco Caparrini1 , Klaus Seidel1 are the basis for radiometric correction. Considering SAR images, the huge amount of processing for geographic and geometric calibration and registration that is needed prior to analysis is well established. Nonetheless

  18. Dropwise condensation on superhydrophobic surfaces with two-tier roughness

    E-Print Network [OSTI]

    Chen, Chuan-Hua

    Dropwise condensation on superhydrophobic surfaces with two-tier roughness Chuan-Hua Chen,a Qingjun condensation. Superhydrophobicity appears ideal to promote continued dropwise condensation which requires rapid. This letter reports continuous dropwise condensation on a superhydrophobic surface with short carbon nanotubes

  19. Turbine airfoil with outer wall thickness indicators

    DOE Patents [OSTI]

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

    2013-08-06T23:59:59.000Z

    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.

  20. 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.

    1999-07-01T23:59:59.000Z

    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.

  1. Heat transfer between elastic solids with randomly rough surfaces

    E-Print Network [OSTI]

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

    2009-08-27T23:59:59.000Z

    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.

  2. Separate effects of surface roughness, wettability, and porosity on the boiling critical heat flux

    E-Print Network [OSTI]

    O'Hanley, Harry

    The separate effects of surface wettability, porosity, and roughness on the critical heat flux (CHF) of water were examined using engineered surfaces. Values explored were 0, 5, 10, and 15??m for Rz (roughness), <5°, ?75°, ...

  3. Systematic Evaluation of Jc Decrease in Thick Film Coated Conductors

    SciTech Connect (OSTI)

    Alex Ignatiev; Dr. Amit Goyal

    2006-05-10T23:59:59.000Z

    Address both thickness dependence of Jc, in thick film YBCO coated conductors through an application of a suite of new measurement techniques to thick film wire samples produced by commercially viable coated conductor technologies.

  4. Thin, thick and dark discs in LCDM

    E-Print Network [OSTI]

    J. I. Read; G. Lake; O. Agertz; Victor P. Debattista

    2008-06-26T23:59:59.000Z

    In a LCDM cosmology, the Milky Way accretes satellites into the stellar disc. We use cosmological simulations to assess the frequency of near disc plane and higher inclination accretion events, and collisionless simulations of satellite mergers to quantify the final state of the accreted material and the effect on the thin disc. On average, a Milky Way-sized galaxy has 3 subhalos with vmax>80km/s; 7 with vmax>60km/s; and 15 with vmax>40km/s merge at redshift z>1. Assuming isotropic accretion, a third of these merge at an impact angle disc plane by dynamical friction. Their accreted stars and dark matter settle into a thick disc. The stellar thick disc qualitatively reproduces the observed thick disc at the solar neighbourhood, but is less massive by a factor ~2-10. The dark matter disc contributes 0.25-1 times the halo density at the solar position. Although not likely to be dynamically interesting, the dark disc has important implications for the direct detection of dark matter because of its low velocity with respect to the Earth. Higher inclination encounters (>20 degrees) are twice as likely as low inclination ones. These lead to structures that closely resemble the recently discovered inner/outer stellar halos. They also do more damage to the Milky Way stellar disc creating a more pronounced flare, and warp; both long-lived and consistent with current observations. The most massive mergers (vmax>80km/s) heat the thin disc enough to produce a thick disc. These heated thin disc stars are essential for obtaining a thick disc as massive as that seen in the Milky Way; they likely comprise some ~50-90% of the thick disc stars. The Milky Way thin disc must reform from fresh gas after z=1 [abridged].

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

    E-Print Network [OSTI]

    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

  6. 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

  7. Gas turbine bucket wall thickness control

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

    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.

  8. Effect of Thickness on the Structure, Composition and Properties...

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

    Effect of Thickness on the Structure, Composition and Properties of Titanium Nitride Nano-Coatings. Effect of Thickness on the Structure, Composition and Properties of Titanium...

  9. 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

    2011-04-14T23:59:59.000Z

    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.

  10. Free Energy of thick Center Vortices

    E-Print Network [OSTI]

    Ch. Korn; H. Reinhardt; T. Tok

    2005-08-05T23:59:59.000Z

    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.

  11. 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)

    2014-10-28T23:59:59.000Z

    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.

  12. " Rotating, In Plane Magnetization and Magneto-Optic Imaging of Cracks in Thick-Section Steel Under Stainless-Steel Cladding".

    SciTech Connect (OSTI)

    Gerald Fitzpatrick & Richard Skaugset

    2000-10-13T23:59:59.000Z

    The nondestructive inspection (NDI) of thick-section steel nuclear reactor pressure vessels (RPV'S) is rendered difficult by rough stainless steel cladding. Because the cladding condition is poorly known in most RPV's, an NDI technique that is unaffected by cladding roughness would be a major advance. Magneto-optic imaging is one such technique. The purpose of this project was to develop a novel method to induce rotating, in-plane magnetization, and to combine this capability with magneto-optic imaging to produce a self-contained inspection system. Imaging of cracks under thick cladding (0.250 inches) was demonstrated using a system capable, in principle, of performing robotic inspections, both inside & outside a typical boiling water reactor (BWR) RPV. This report, together publications listed, constitutes a comprehensive account of this work.

  13. IMPACT OF DIELECTRIC PARAMETERS ON THE REFLECTIVITY OF 3C-SiC WAFERS WITH A ROUGH SURFACE MORPHOLOGY IN THE RESTSTRAHLEN REGION

    SciTech Connect (OSTI)

    J.A.A. Engelbrecht; E. Janzén; A. Henry; I.J. van Rooyen

    2014-04-01T23:59:59.000Z

    A layer-on-substrate model is used to obtain the infrared reflectance for 3C-SiC with a rough surface morphology. The effect of varying dielectric parameters of the “damaged layer” on the observed reflectivity of the 3C-SiC in the reststrahlen region is assessed. Different simulated reflectance spectra are obtained to those if the dielectric parameters of the “substrate” were varied. Most notable changes in the shape of the simulated reststrahlen peak are observed for changes in the high frequency dielectric constant, the phonon damping constant, the phonon frequencies and “thickness” of damaged surface layer.

  14. Semiclassical Theory of Integrable and Rough Andreev Billiards

    E-Print Network [OSTI]

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

    1999-09-08T23:59:59.000Z

    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.

  15. Ultrasonic thickness testing of aging offshore structures

    E-Print Network [OSTI]

    Ellison, Brian Kirk

    1999-01-01T23:59:59.000Z

    . 14 2. 15 2. 16 2. 17 2. 18 New Anode. Spent Anode 1989 JIP Specimens. Dual Transducer Sound Paths. Specimens for Feasibility Studies (View I). Specimens for Feasibility Studies (View 2) . General Nomenclature. Transducer / Surface... study in an attempt to improve the effectiveness of ultrasonic thickness testing. Motivation for research stems from a joint industry project (JIP) that took place at Texas AIkM University (TAMU) from 1989 to 1990 (Moehlman 1990). In 1989, several...

  16. Local contact stress measurements at a rough interface

    E-Print Network [OSTI]

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

    2007-11-07T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Ganapati, Vidya; Yablonovitch, Eli

    2013-01-01T23:59:59.000Z

    Light trapping in solar cells allows for increased current and voltage, as well as reduced materials cost. It is known that in geometrical optics, a maximum 4n^2 absorption enhancement factor can be achieved by randomly texturing 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. In sub-wavelength thin films, the fundamental questions remain unanswered: (1) what is the sub-wavelength absorption enhancement limit and (2) what surface texture realizes this optimal absorption enhancement? We turn to computational electromagnetic optimization in order to design nanoscale textures for light trapping in sub-wavelength thin films. For high-index thin films, in the weakly absorbing limit, our optimized surface textures yield an angle- and frequency-averaged enhancement factor ~39. They perform roughly 30% better than randomly textured structures, but they fall...

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

    E-Print Network [OSTI]

    Neelesh A. Patankar

    2015-05-22T23:59:59.000Z

    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.

  19. Skin thickness effects on in vivo LXRF

    SciTech Connect (OSTI)

    Preiss, I.L.; Washington, W. II [Rensselaer Polytechnic Inst., Troy, NY (United States)

    1995-12-31T23:59:59.000Z

    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.

  20. Nanoscale Surface and Interface Mechanics of Elastic-Plastic Media with Smooth, Patterned, and Rough Surfaces

    E-Print Network [OSTI]

    Yin, Xi

    2011-01-01T23:59:59.000Z

    patterning, rough surface topography, interfacial adhesion,media with fractal surface topographies. J. Tribol. 123,representative of the 3D surface topography. A 2D profile of

  1. Lyapunov instability of rough hard-disk fluids

    E-Print Network [OSTI]

    Jacobus A. van Meel; Harald A. Posch

    2009-04-02T23:59:59.000Z

    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 $I$.

  2. Mapping crustal thickness using marine gravity data: Methods and uncertainties

    E-Print Network [OSTI]

    Müller, Dietmar

    of petroleum systems within passive margins. However, direct measurements of crustal thickness are sparse geophysical data, to estimate crustal thickness. We evaluated alternative gravity inversion methodol- ogies, but economic considerations make gravity modeling a more practical approach for mapping crustal thickness over

  3. The influence of the AlN barrier thickness on the polarization Coulomb field scattering in AlN/GaN heterostructure field-effect transistors

    SciTech Connect (OSTI)

    Lv, Yuanjie; Feng, Zhihong, E-mail: ga917vv@163.com; Gu, Guodong; Han, Tingting; Yin, Jiayun; Liu, Bo; Cai, Shujun [National Key Laboratory of Application Specific Integrated Circuit (ASIC), Hebei Semiconductor Research Institute, Shijiazhuang 050051 (China); Lin, Zhaojun; Ji, Ziwu; Zhao, Jingtao [School of Physics, Shandong University, Jinan 250100 (China)

    2014-07-14T23:59:59.000Z

    The electron mobility scattering mechanisms in AlN/GaN heterostuctures with 3?nm and 6?nm AlN barrier thicknesses were investigated by temperature-dependent Hall measurements. The effect of interface roughness (IFR) scattering on the electron mobility was found to be enhanced by increasing AlN barrier thickness. Moreover, using the measured capacitance-voltage and current-voltage characteristics of the fabricated heterostructure field-effect transistors (HFETs) with different Schottky areas on the two heterostuctures, the variations of electron mobility with different gate biases were investigated. Due to enhanced IFR scattering, the influence of polarization Coulomb field (PCF) scattering on electron mobility was found to decrease with increasing AlN barrier layer thickness. However, the PCF scattering remained an important scattering mechanism in the AlN/GaN HFETs.

  4. Radioactive waste disposal in thick unsaturated zones

    SciTech Connect (OSTI)

    Winograd, I.J.

    1981-06-26T23:59:59.000Z

    Portions of the Great Basin are undergoing crustal extension and have unsaturated zones as much as 600 meters thick. These areas contain multiple natural barriers capable of isolating solidified toxic wastes from the biosphere for tens of thousands to perhaps hundreds of thousands of years. An example of the potential utilization of such arid zone environments for toxic waste isolation is the burial of transuranic radioactive wastes at relatively shallow depths (15 to 100 meters) in Sedan Crater, Yucca Flat, Nevada. The volume of this man-made crater is several times that of the projected volume of such wastes to the year 2000. Disposal in Sedan Crater could be accomplished at a savings on the order of $0.5 billion, in comparison with current schemes for burial of such wastes in mined repositories at depths of 600 to 900 meters, and with an apparently equal likelihood of waste isolation from the biosphere. 4 figures.

  5. Introduction to the Special Issue on Rough Sets and Soft Computing.

    E-Print Network [OSTI]

    Lin, Tsau Young

    of information systems. From the outset, rough set theory has been a methodology of database mining or knowledge, neighborhood systems, neural network, and soft computing. In real world applications, we see papers in Introduction to the Special Issue on Rough Sets and Soft Computing. T. Y. Lin Department

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

    E-Print Network [OSTI]

    Bane, K

    2014-01-01T23:59:59.000Z

    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%.

  7. EFFECT OF CONTACT VISCOSITY AND ROUGHNESS ON INTERFACE STIFFNESS AND WAVE PROPAGATION

    E-Print Network [OSTI]

    Boyer, Edmond

    EFFECT OF CONTACT VISCOSITY AND ROUGHNESS ON INTERFACE STIFFNESS AND WAVE PROPAGATION Anil Misra1 and asperity properties compete in determining the stiffness behavior, and consequently, the wave propagation widely used to investigate plane wave propagation through contacts between two rough solids [see

  8. 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

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

    E-Print Network [OSTI]

    Heinemann, Detlev

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

  10. Dependence of friction on roughness, velocity, and temperature Martin Dub,2

    E-Print Network [OSTI]

    Grant, Martin

    - faces were discovered long ago by Da Vinci, Amonton, and Coulomb. They found that friction is i, and friction at the macroscopic level is now well understood, for both dry rough 3 and lubricated surfaces 4Dependence of friction on roughness, velocity, and temperature Yi Sang,1 Martin Dubé,2 and Martin

  11. 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

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

    E-Print Network [OSTI]

    Svend-Age Biehs; Jean-Jacques Greffet

    2011-03-11T23:59:59.000Z

    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. Ultrasonic thickness measuring and imaging system and method

    DOE Patents [OSTI]

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

    1992-08-04T23:59:59.000Z

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

  14. Ultrasonic thickness measuring and imaging system and method

    DOE Patents [OSTI]

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

    1992-01-01T23:59:59.000Z

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

  15. Cladding Attachment Over Thick Exterior Insulating Sheathing

    SciTech Connect (OSTI)

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

    2014-01-01T23:59:59.000Z

    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?

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

    E-Print Network [OSTI]

    Xie, Yu

    2007-09-17T23:59:59.000Z

    The effect of the surface roughness of ice crystals is not routinely accounted for in current cloud retrieval algorithms that are based on pre-computed lookup libraries. In this study, we investigate the effect of ice crystal surface roughness...

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

    E-Print Network [OSTI]

    T. V. Nykytyuk; T. V. Mishenina

    2006-05-26T23:59:59.000Z

    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.

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

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

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

  19. Thickness dependent self limiting 1-D tin oxide nanowire arrays...

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

    dependent self limiting 1-D tin oxide nanowire arrays by nanosecond pulsed laser irradiation. Thickness dependent self limiting 1-D tin oxide nanowire arrays by nanosecond pulsed...

  20. ag thick film: Topics by E-print Network

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

    applied. Yagi, Kazuyuki 2006-01-01 23 In situ Simultaneous Measurement of Temperature and Thin Film Thickness with Ultrasonic Techniques Engineering Websites Summary: In situ...

  1. artery wall thickness: Topics by E-print Network

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

    (CCA-IMT) were measured using ultrasonography. Gait 22 LIFE CYCLE ASSESSMENT OF A HEMP CONCRETE WALL: IMPACT OF THICKNESS AND COATING. Physics Websites Summary: to reduce...

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

    Open Energy Info (EERE)

    Crustal Thickness In The Western Great Basin- A Compilation Of Old And New Refraction Data Abstract Utilizing commercial mine blasts and local earthquakes, as well as a dense...

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

    DOE Patents [OSTI]

    Bernitsas, Michael M; Raghavan, Kamaldev

    2014-04-01T23:59:59.000Z

    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.

  4. Boundary-Layer Receptivity to Three-Dimensional Roughness Arrays on a Swept-Wing

    E-Print Network [OSTI]

    Hunt, Lauren Elizabeth

    2012-02-14T23:59:59.000Z

    is required. This study uses detailed hotwire boundary-layer velocity scans to quantify the relationship between roughness height and initial disturbance amplitude. Naphthalene flow visualization provides insight into how transition changes as a result...

  5. Thermoelectric characteristic of the rough InN/GaN core-shell nanowires

    SciTech Connect (OSTI)

    Wu, Chao-Wei; Wu, Yuh-Renn, E-mail: yrwu@ntu.edu.tw [Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2014-09-14T23:59:59.000Z

    An analysis to model the thermoelectric (TE) effects of the rough InN/GaN core-shell nanowires (NWs) with wire diameter ranging from 25?nm to 100?nm is proposed. The elastic continuum model is employed to calculate the phonon dispersion relation curves and the related phonon group velocity. Within the framework of Boltzmann transport equations and relaxation time approximation, the electrical conductivity, Seebeck coefficient, electronic thermal conductivity, and the lattice thermal conductivity is obtained. Simulation results indicate that TE properties of the rough InN/GaN core-shell NWs are strongly affected by the surface roughness and the diameter of NWs. The optimized condition of the proposed rough InN/GaN core-shell TE NWs is studied in this paper and the highest ZT obtained in the calculation is 0.8598 at 300?K and 1.713 at 1000?K.

  6. A construction of the rough path above fractional Brownian motion using Volterra’s representation

    E-Print Network [OSTI]

    Nualart, David; Tindel, Samy

    2011-09-01T23:59:59.000Z

    This note is devoted to construct a rough path above a multidimensional fractional Brownian motion B with any Hurst parameter H?(0,?1), by means of its representation as a Volterra Gaussian process. This approach yields ...

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

    DOE Patents [OSTI]

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

    2011-11-01T23:59:59.000Z

    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).

  8. Dual frequency microwave radiometer measurements of soil moisture for bare and vegetated rough surfaces

    E-Print Network [OSTI]

    Lee, Siu Lim

    1974-01-01T23:59:59.000Z

    DUAL FREQUENCY MICROWAVE RADIOMETER MEASUREMENTS OF SOIL MOISTURE FOR BARE AND VEGETATED ROUGH SURFACES A Thesis by SIU LIM LEE Submitted to the Graduate College of Texas A(M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE August 1974 Major Subject: Electrical Engineering DUAL FREQUENCY MICROWAVE RADIOMETER MEASUREMENTS OF' SOIL MOISTURE FOR BARE AND VEGETATED ROUGH SURFACES A Thesis by SIU LIM LEE Approved as to style and content by: (C rman...

  9. PAVEMENT OVERLAY THICKNESS EVALUATION USING GROUND PENTRATING RADAR (GPR)

    E-Print Network [OSTI]

    Shan, Jie

    PAVEMENT OVERLAY THICKNESS EVALUATION USING GROUND PENTRATING RADAR (GPR) Dwayne Harris, M.Sc., PG University, West Lafayette, IN 47907 jshan@ecn.purdue.edu ABSTRACT Accurate knowledge of pavement thickness is important information to have both at a network and project level. This information aids in pavement

  10. M AERIAUXMAGNETIQUES POUR HYPERFREQUENCES THICK FERRITE FILMS BY CHEMICAL TRANSPORT

    E-Print Network [OSTI]

    Boyer, Edmond

    M AERIAUXMAGNETIQUES POUR HYPERFREQUENCES THICK FERRITE FILMS BY CHEMICAL TRANSPORT A. I. BRAGINSKI-Mn ferrite and ferrochrornite films by Chemical Transport Deposi- tion (CTD) [I, 21. This method properties obtained. CTD now appears to be a valuable tool in laboratory preparation of thick ferrite layers

  11. A model for variable thickness superconducting thin lms

    E-Print Network [OSTI]

    Chapman, Jon

    A model for variable thickness superconducting thin #12;lms S. J. Chapman #3; Mathematical for Applied Mathematics Virginia Tech Blacksburg VA 24061-0531, USA Abstract A model for superconductivity. When the #12;lm is of uniform thickness the model is identical to a model for superconducting cylinders

  12. 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

  13. 6D thick branes from interacting scalar fields

    SciTech Connect (OSTI)

    Dzhunushaliev, Vladimir; Folomeev, Vladimir; Singleton, Douglas; Aguilar-Rudametkin, Sergio [Department of Physics and Microel. Engineering, Kyrgyz-Russian Slavic University, Bishkek, Kievskaya Str. 44, 720021 (Kyrgyzstan); Institute of Physics of NAS KR, 265 a, Chui str., Bishkek, 720071 (Kyrgyzstan); Physics Department, CSU Fresno, Fresno, California 93740-8031 (United States)

    2008-02-15T23:59:59.000Z

    A thick brane in six dimensions is constructed using two scalar fields. The field equations for 6D gravity plus the scalar fields are solved numerically. This thick brane solution shares some features with previously studied analytic solutions, but has the advantage that the energy-momentum tensor which forms the thick brane comes from the scalar fields rather than being put in by hand. Additionally the scalar fields which form the brane also provide a universal, nongravitational trapping mechanism for test fields of various spins.

  14. 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)

    2002-01-01T23:59:59.000Z

    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.

  15. Stochastic modeling of random roughness in shock scattering problems: theory and simulations

    SciTech Connect (OSTI)

    Lin, Guang; Su, Chau-Hsing; Karniadakis, George E.

    2008-08-01T23:59:59.000Z

    Random rougness is omnipresent in engineering applications and may often affect performance in unexpected way. Here, we employ synergistically stochastic simulations and second-order stochastic perturbation analysis to study supersonic flow past a wedge with random rough surface. The roughness (of length $d$) starting at the wedge apex is modeled as stochastic process (with zero mean and correlation length $A$) obtained from a new stochastic differential equation. A multi-element probabilistic collocation method (ME-PCM) based on {\\em sparse grids} is employed to solve the stochastic Euler equations while a WENO scheme is used to discretize the equations in two spatial dimensions. The perturbation analysis is used to verify the stochastic simulations and to provide insight for small values of $A$, where stochastic simulations become prohibitively expensive. % We show that the random roughness enhances the lift and drag forces on the wedge beyond the rough region, and this enhancement is proportional to $(d/A)^2$. The effects become more pronounced as the Mach number increases. These results can be used in designing smart rough skins for airfoils for maxiumum lift enhancement at a minimum drag penalty.

  16. 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

    2015-02-10T23:59:59.000Z

    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.

  17. THROUGH THICKNESS LASER JOINING OF CONTINUOUS GLASS FIBER FABRIC REINFORCEMENT

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    THROUGH THICKNESS LASER JOINING OF CONTINUOUS GLASS FIBER FABRIC REINFORCEMENT Paper Number 405 Huade Tan, Gen Satoh, Y. Lawrence Yao Manufacturing Research Laboratory Department of Mechanical and propagation is a major failure mode in structural composite applications. Manufacturing induced fiber

  18. Coherent radar ice thickness measurements over the Greenland ice sheet

    E-Print Network [OSTI]

    Gogineni, S. Prasad; Tammana, Dilip; Braaten, David A.; Leuschen, C.; Legarsky, J.; Kanagaratnam, P.; Stiles, J.; Allen, C.; Jezek, K.; Akins, T.

    2001-12-27T23:59:59.000Z

    We developed two 150-MHz coherent radar depth sounders for ice thickness measurements over the Greenland ice sheet. We developed one of these using connectorized components and the other using radio frequency integrated circuits (RFICs). Both...

  19. Thru-thickness bending stress distribution at elevated temperatures

    E-Print Network [OSTI]

    Christian, Lee Conner

    2005-08-29T23:59:59.000Z

    the extreme fiber strains exceeded ten percent, which further adds to the increased risk of the flange plate cracking during fabrication. The highest residual stresses through the plate??s thickness occurred during cold bending. The residual stresses through...

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

    E-Print Network [OSTI]

    Bloore, David A. (David Allan)

    2013-01-01T23:59:59.000Z

    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 ...

  1. airway wall thickness: Topics by E-print Network

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

    18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 21 LIFE CYCLE ASSESSMENT OF A HEMP CONCRETE WALL: IMPACT OF THICKNESS AND COATING. Physics Websites Summary: to reduce...

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

    E-Print Network [OSTI]

    Nicholas Guttenberg; Nigel Goldenfeld

    2009-03-25T23:59:59.000Z

    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.

  3. Multiscale characterization method for line edge roughness based on redundant second generation wavelet transform

    SciTech Connect (OSTI)

    Wang Fei; Zhao Xuezeng [School of Mechanical and Electronic Engineering, Harbin Institute of Technology, Harbin 150001 (China); Li Ning [Shanghai Second Polytechnic University, Shanghai 201209 (China)

    2010-10-15T23:59:59.000Z

    We introduce a multiscale characterization method for line edge roughness (LER) based on redundant second generation wavelet transform. This method involves decomposing LER characteristics into independent bands with different spatial frequency components at different scales, and analyzing the reconstructed signals to work out the roughness exponent, the spatial frequency distribution characteristics, as well as the rms value. The effect of noise can be predicted using detailed signals in the minimum space of scale. This method was applied to numerical profiles for validation. Results show that according to the line edge profiles with similar amplitudes, the roughness exponent R can effectively reflect the degree of irregularity of LER and intuitively provide information on LER spatial frequency distribution.

  4. Validity of the thin mask approximation in extreme ultraviolet mask roughness simulations

    SciTech Connect (OSTI)

    Naulleau, Patrick; George, Simi

    2011-01-26T23:59:59.000Z

    In the case of extreme ultraviolet (EUV) lithography, modeling has shown that reflector phase roughness on the lithographic mask is a significant concern due to the image plan speckle it causes and the resulting line-edge roughness on imaged features. Modeling results have recently been used to determine the requirements for future production worthy masks yielding the extremely stringent specification of 50 pm rms roughness. Owing to the scale of the problem in terms of memory requirements, past modeling results have all been based on the thin mask approximation. EUV masks, however, are inherently three dimensional in nature and thus the question arises as to the validity of the thin mask approximation. Here we directly compare image plane speckle calculation results using the fast two dimensional thin mask model to rigorous finite-difference time-domain results and find the two methods to be comparable.

  5. Surface roughness of stainless-steel mirrors for focusing soft x rays

    SciTech Connect (OSTI)

    Yashchuk, Valeriy V.; Gullikson, Eric M.; Howells, Malcolm R.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R.; Salmassi, Farhad; Warwick, Tony; Metz, James P.; Tonnessen, Thomas W

    2006-07-10T23:59:59.000Z

    We have used polished stainless steel as a mirror substrate to provide focusing of soft x rays in grazing-incidence reflection. The critical issue of the quality of the steel surface,polished and coated with gold, is discussed in detail. A comparison is made to a polished,gold-coated, electroless nickel surface, which provides a smoother finish. We used the surface height distributions, measured with an interferometric microscope and complemented by atomic-force microscope measurements, to compute power spectral densities and then to evaluate the surface roughness. The effects of roughness in reducing the specular reflectivity were verified by soft-x-ray measurements.

  6. Annealing temperature and thickness dependence of magnetic properties in epitaxial L1{sub 0}-Mn{sub 1.4}Ga films

    SciTech Connect (OSTI)

    Zheng, Y. H., E-mail: elezheng@nus.edu.sg; Lu, H.; Teo, K. L. [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore); Han, G. C. [Data Storage Institute, 5 Engineering Drive 1, Singapore 117608 (Singapore)

    2014-01-28T23:59:59.000Z

    Mn{sub 1.4}Ga films with high perpendicular magnetic anisotropy and high crystalline quality were grown on MgO substrates with Cr buffer layer using molecular beam epitaxy. The crystalline structure and the surface morphology of the films have been systematically investigated as functions of in-situ annealing temperature (T{sub a}) and film thickness. It is found that the magnetic properties can be largely tuned by adjusting T{sub a}. As T{sub a} increases, both saturation magnetization (M{sub s}) and uniaxial perpendicular magnetic anisotropy constant (K{sub u}) increase to the maximum values of 612?emu/cc and 18?Merg/cc at 300?°C, respectively, and then decrease. The morphology also changes with T{sub a}, showing a minimum roughness of 2.2?Å at T{sub a}?=?450?°C. On the other hand, as the thickness increases, M{sub s} and K{sub u} increase while coercivity decreases, which indicates there is a magnetic dead layer with a thickness of about 1.5?nm at the interfaces. The detailed examination on the surface morphology of the films with various thicknesses shows a complicated film growth process, which can be understood from the relaxation mechanism of the interfacial strain.

  7. 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)

    2003-01-01T23:59:59.000Z

    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.

  8. Development of a Hybrid Powered 2D Biped Walking Machine Designed for Rough Terrain Locomotion

    E-Print Network [OSTI]

    Baker, Bryce C.

    2010-07-28T23:59:59.000Z

    has built a three legged 2D biped walking machine to be used as a test stand for studying rough terrain walking. The specific aim of this research is to investigate how biped walkers can best maintain walking stability when acted upon by small...

  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. Geometrical and transport properties of single fractures: influence of the roughness of the fracture

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and more particularly in the design and safety of nuclear power plants or cryotechnic rocket engines, where space is found to be crucially function of the failure mechanism (brittle, quasi brittle or plastic influencing the structure of the void space. Studies devoted to the characterization of the surface roughness

  12. Optimization of Hard Material Roughing by means of a Stability , M. Zatarain2

    E-Print Network [OSTI]

    Boyer, Edmond

    Self-excited vibrations limit the productivity of aluminium and steel roughing. During aluminium they are associated to the structure of the machine tool (low frequency). For aluminium, the dynamic characterisation the usual one applied in light alloys. The proposed model is verified experimentally in a practical case

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

    E-Print Network [OSTI]

    Schmittbuhl, Jean

    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

  14. Tsunami generated by a granular collapse down a rough inclined S. Viroulet1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    epl draft Tsunami generated by a granular collapse down a rough inclined plane S. Viroulet1 , A Jersey 08544, USA PACS 47.57.Gc ­ Granular flow, complex fluids PACS 92.10.hl ­ Tsunamis PACS 45.70.Ht wave and the evolution of its amplitude during the propagation. The experiments show that whereas

  15. Measurement of friction noise versus contact area of rough surfaces weakly loaded

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    contact area. The friction-induced vibration is generated by the sliding of two rough surfaces. The normal load is low leading to a weak contact. The normal load and the sliding velocity are maintained constant], friction noises can be classified in two types depending on the contact pressure. When the contact pressure

  16. Sensitivity of Swept-Wing, Boundary-Layer Transition to Spanwise-Periodic Discrete Roughness Elements

    E-Print Network [OSTI]

    West, David Edward

    2014-12-12T23:59:59.000Z

    Micron-sized, spanwise-periodic, discrete roughness elements (DREs) were applied to and tested on a 30° swept-wing model in order to study their effects on boundary-layer transition in flight where stationary crossflow waves are the dominant...

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

    E-Print Network [OSTI]

    to Manning's formula. The Task Force on Friction Factors in Open Channel 1963 found that Manning's formula's formula in heavily vegetated or urbanized areas is particularly problematic Task Force on Friction Factors is the relationship among wind speed, friction velocity, and the surface roughness that was developed from Prandtl

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

    E-Print Network [OSTI]

    Heinemann, Detlev

    sites. The first large offshore wind farms are currently being built in several countries in EuropeImportance 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

  19. ROUGH SURFACES OF TITANIUM AND TITANIUM ALLOYS FOR IMPLANTS AND PROSTHESES

    E-Print Network [OSTI]

    Boyer, Edmond

    ROUGH SURFACES OF TITANIUM AND TITANIUM ALLOYS FOR IMPLANTS AND PROSTHESES 1 E. Conforto, 2 B. Abstract Titanium and titanium alloys for dental implants and hip prostheses were surface-treated and and the stability of the implant. The microstructure of titanium and titanium alloys submitted to these treatments

  20. Rough-Fuzzy C-Medoids Algorithm and Selection of Bio-Basis for Amino Acid

    E-Print Network [OSTI]

    Pal, Sankar Kumar

    of protein data sets. Index Terms--Pattern recognition, data mining, c-medoids algorithm, fuzzy sets, rough Pradipta Maji and Sankar K. Pal, Fellow, IEEE Abstract--In most pattern recognition algorithms, amino acids pattern recognition algorithms to analyze these biological subsequences is that they cannot recognize

  1. Soft data mining, computational theory of perceptions, and rough-fuzzy approach

    E-Print Network [OSTI]

    Pal, Sankar Kumar

    is described from pattern recognition point of view along with the relevance of soft computing. Key features of the computational theory of perceptions and its significance in pattern recognition and knowledge dis- covery, and its modeling through rough-fuzzy integration are discussed. Merits of fuzzy granular computation

  2. Class-dependent rough-fuzzy granular space, dispersion index and classification

    E-Print Network [OSTI]

    Pal, Sankar Kumar

    granular computing Soft computing Pattern recognition Remote sensing a b s t r a c t A new rough-fuzzy model for pattern classification based on granular computing is described in the present article. In this model, we propose the formulation of class-dependent granules in fuzzy environment. Fuzzy membership

  3. 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

  4. An FDTD Method for Analysis of Scattering from Rough FluidFluid Interfaces

    E-Print Network [OSTI]

    Schneider, John B.

    results are presented for fluid­fluid cases modeling water­sediment inter­ faces. Two different roughness speeds in shallow­water sediment bottoms are relatively slow, a fluid­ fluid model is a reasonable to the interface, and a correc­ tion for the numerical dispersion inherent to the FDTD algorithm. Numeri­ cal

  5. Particle acceleration in thick parallel shocks with high compression ratio

    E-Print Network [OSTI]

    Joni J. P. Virtanen; Rami Vainio

    2005-06-06T23:59:59.000Z

    We report studies on first-order Fermi acceleration in parallel modified shock waves with a large scattering center compression ratio expected from turbulence transmission models. Using a Monte Carlo technique we have modeled particle acceleration in shocks with a velocity ranging from nonrelativistic to ultrarelativistic and a thickness extending from nearly steplike to very wide structures exceeding the particle diffusion length by orders of magnitude. The nonrelativistic diffusion approximation is found to be surprisingly accurate in predicting the spectral index of a thick shock with large compression ratio even in the cases involving relativistic shock speeds.

  6. Process for manufacture of thick film hydrogen sensors

    DOE Patents [OSTI]

    Perdieu, Louisa H. (Overland Park, KS)

    2000-09-09T23:59:59.000Z

    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.

  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

    2001-01-01T23:59:59.000Z

    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. Liquid film thickness measurement by two-line TDLAS

    SciTech Connect (OSTI)

    Yang, Huinan [School of Energy and Power Engineering, University of Shanghai for Science and Technology, 200093, Shanghai, China and IVG, University of Duisburg-Essen, 47057, Duisburg (Germany); Chen, Jun; Cai, Xiaoshu [School of Energy and Power Engineering, University of Shanghai for Science and Technology, 200093, Shanghai (China); Greszik, Daniel; Dreier, Thomas; Schulz, Christof [IVG, University of Duisburg-Essen, 47057, Duisburg (Germany)

    2014-04-11T23:59:59.000Z

    A fiber-based two-line tunable diode-laser absorption sensor with two near-infrared (NIR) distributed-feedback (DFB) diode lasers at ?1.4 ?m was used for non-intrusive time-resolved liquid water film thickness measurement. When probing the liquid film at two different wavelengths with significantly different absorption cross-sections, the additional signal losses due to surface fowling, reflection and beam steering can be eliminated. In this work, the evaporation process of a liquid film on transparent quartz plate was tracked and large fluctuations of film thickness were found at the end of the evaporation.

  9. Equivalent roughness height for plane bed under oscillatory flow Benoi^t Camenen a,*, Magnus Larson b

    E-Print Network [OSTI]

    US Army Corps of Engineers

    of a flat and fixed bed is given in terms of the Nikuradse roughness height (ks). For flat beds larger than for a fixed bed. This is probably caused by the increased energy dissipation in the sheetEquivalent roughness height for plane bed under oscillatory flow Benoi^t Camenen a,*, Magnus Larson

  10. 486 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, VOL. 17, NO. 7, JULY 2007 Estimation of Roughness-Induced Power Absorption

    E-Print Network [OSTI]

    Tsang, Leung

    it to predict the roughness effect on power loss. Index Terms--Power absorption, power spectral density (PSD significant additional power loss that can be detrimental for insertion loss limited designs. We recently interconnect surfaces and use it to estimate corresponding roughness-induced power loss. The 2-D PSD

  11. Structural connections in plywood friction-fit construction

    E-Print Network [OSTI]

    Wagner, Mali E. (Mali Esther)

    2014-01-01T23:59:59.000Z

    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. The Museum Theorem: Thick Face-Paths and

    E-Print Network [OSTI]

    West, Douglas B.

    The Museum Theorem: Thick Face-Paths and Hamiltonian-Connectedness in Plane Graphs Xiaoyun Lu #12;Visiting a Museum The Problem: The entrance and exit of a museum are fixed. You insist on visiting room F. The pieces of what you skip should be somehow "small". #12;Visiting a Museum The Problem

  13. THE TURBULENCE POWER SPECTRUM IN OPTICALLY THICK INTERSTELLAR CLOUDS

    SciTech Connect (OSTI)

    Burkhart, Blakesley; Lazarian, A. [Astronomy Department, University of Wisconsin, Madison, 475 North Charter Street, WI 53711 (United States); Ossenkopf, V.; Stutzki, J. [Physikalisches Institut der Universitaet zu Koeln, Zuelpicher Strasse 77, D-50937 Koeln (Germany)

    2013-07-10T23:59:59.000Z

    The Fourier power spectrum is one of the most widely used statistical tools to analyze the nature of magnetohydrodynamic (MHD) turbulence in the interstellar medium. Lazarian and Pogosyan predicted that the spectral slope should saturate to -3 for an optically thick medium and many observations exist in support of their prediction. However, there have not been any numerical studies to date for testing these results. We analyze the spatial power spectrum of MHD simulations with a wide range of sonic and Alfvenic Mach numbers, which include radiative transfer effects of the {sup 13}CO transition. We numerically confirm the predictions of Lazarian and Pogosyan that the spectral slope of line intensity maps of an optically thick medium saturates to -3. Furthermore, for very optically thin supersonic CO gas, where the density or CO abundance values are too low to excite emission in all but the densest shock compressed gas, we find that the spectral slope is shallower than expected from the column density. Finally, we find that mixed optically thin/thick CO gas, which has average optical depths on the order of unity, shows mixed behavior: for super-Alfvenic turbulence, the integrated intensity power spectral slopes generally follow the same trend with sonic Mach number as the true column density power spectrum slopes. However, for sub-Alfvenic turbulence the spectral slopes are steeper with values near -3 which are similar to the very optically thick regime.

  14. Thick brane solutions supported by two spinor fields

    E-Print Network [OSTI]

    V. Dzhunushaliev; V. Folomeev

    2011-04-14T23:59:59.000Z

    Stationary thick brane solutions supported by two spinor fields are considered. Two spinor fields are used here to exclude the off-diagonal components of the energy-momentum tensor of the spinor fields. The trapping of a test scalar field on the brane is also considered.

  15. Sensing roller for in-process thickness measurement

    DOE Patents [OSTI]

    Novak, J.L.

    1996-07-16T23:59:59.000Z

    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.

  16. Measurement of Paint Layer Thickness with Photothermal Infrared Radiometry

    E-Print Network [OSTI]

    Louis, Alfred K.

    - try [1, 2]. As input for remote control systems, thickness information has to be supplied in realtime. Data acquisition has to be perfomed in a non-contact man- ner. Not only non-destructive and remote a periodical heat source on, respectively within, the sample then we waste a lot of information if only the #12

  17. An analytic description of thick-wall bubbles

    SciTech Connect (OSTI)

    Hong, Jooyoo

    1992-08-01T23:59:59.000Z

    A new approximation scheme to the false-vacuum decay is suggested. In this scheme the bounce solutions can be obtained in an explicit and analytic way even for thick-wall bubbles. The result is compared with Coleman`s thin-wall description, which shows that is nicely comprises the result of the latter prescription. Some applications are also discussed.

  18. LBNL 59017 JArt 1 Improved Spatial Resolution in Thick, Fully-

    E-Print Network [OSTI]

    LBNL 59017 JArt 1 Improved Spatial Resolution in Thick, Fully- Depleted CCDs with Enhanced Red developed at Lawrence Berkeley National Laboratory (LBNL). Because they can be over-depleted, the LBNL measure an rms diffusion of 3.7 ± 0.2 m. Lateral charge diffusion in LBNL CCDs will meet the SNAP

  19. Abundances of metal-weak thick-disc candidates

    E-Print Network [OSTI]

    P. Bonifacio; M. Centurion; P. Molaro

    1999-06-03T23:59:59.000Z

    High resolution spectra of 5 candidate metal-weak thick-disc stars suggested by Beers & Sommer-Larsen (1995) are analyzed to determine their chemical abundances. The low abundance of all the objects has been confirmed with metallicity reaching [Fe/H]=-2.9. However, for three objects, the astrometric data from the Hipparcos catalogue suggests they are true halo members. The remaining two, for which proper-motion data are not available, may have disc-like kinematics. It is therefore clear that it is useful to address properties of putative metal-weak thick-disc stars only if they possess full kinematic data. For CS 22894-19 the abundance pattern similar to those of typical halo stars is found, suggesting that chemical composition is not a useful discriminant between thick-disc and halo stars. CS 29529-12 is found to be C enhanced with [C/Fe]=+1.0; other chemical peculiarities involve the s process elements: [Sr/Fe]=-0.65 and [Ba/Fe]=+0.62, leading to a high [Ba/Sr] considerably larger than what is found in more metal-rich carbon-rich stars, but similar to LP 706-7 and LP 625-44 discussed by Norris et al (1997a). Hipparcos data have been used to calculate the space velocities of 25 candidate metal-weak thick-disc stars, thus allowing us to identify 3 bona fide members, which support the existence of a metal-poor tail of the thick-disc, at variance with a claim to the contrary by Ryan & Lambert (1995).

  20. 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)

    2002-01-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Andrés Santos; Gilberto M. Kremer; Vicente Garzó

    2010-07-16T23:59:59.000Z

    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. Decline in ice thickness from sub data 1 10/16/07 The decline in arctic sea-ice thickness: separating the spatial, annual, and1

    E-Print Network [OSTI]

    Percival, Don

    Decline in ice thickness from sub data 1 10/16/07 The decline in arctic sea-ice thickness/14/07 & 10/16/079 10 11 #12;Decline in ice thickness from sub data 2 10/16/07 Abstract11 Naval submarines have collected operational data of sea-ice draft (90% of thickness) in the12 Arctic Ocean since 1958

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

    E-Print Network [OSTI]

    Carmignani, B

    2005-01-01T23:59:59.000Z

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

  4. 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)]

    Sivaraman, Chitra; Flynn, Connor

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

  5. 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)]

    Newsom, Rob; Goldsmith, John

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

  6. 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

    2015-01-16T23:59:59.000Z

    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 %).

  7. Method for making thick and/or thin film

    DOE Patents [OSTI]

    Pham, Ai Quoc; Glass, Robert S.

    2004-11-02T23:59:59.000Z

    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.

  8. Terahertz inline wall thickness monitoring system for plastic pipe extrusion

    SciTech Connect (OSTI)

    Hauck, J., E-mail: j.hauck@skz.de, E-mail: d.stich@skz.de, E-mail: p.heidemeyer@skz.de, E-mail: m.bastian@skz.de, E-mail: t.hochrein@skz.de; Stich, D., E-mail: j.hauck@skz.de, E-mail: d.stich@skz.de, E-mail: p.heidemeyer@skz.de, E-mail: m.bastian@skz.de, E-mail: t.hochrein@skz.de; Heidemeyer, P., E-mail: j.hauck@skz.de, E-mail: d.stich@skz.de, E-mail: p.heidemeyer@skz.de, E-mail: m.bastian@skz.de, E-mail: t.hochrein@skz.de; Bastian, M., E-mail: j.hauck@skz.de, E-mail: d.stich@skz.de, E-mail: p.heidemeyer@skz.de, E-mail: m.bastian@skz.de, E-mail: t.hochrein@skz.de; Hochrein, T., E-mail: j.hauck@skz.de, E-mail: d.stich@skz.de, E-mail: p.heidemeyer@skz.de, E-mail: m.bastian@skz.de, E-mail: t.hochrein@skz.de [SKZ - German Plastics Center, Wuerzburg (Germany)

    2014-05-15T23:59:59.000Z

    Conventional and commercially available inline wall thickness monitoring systems for pipe extrusion are usually based on ultrasonic or x-ray technology. Disadvantages of ultrasonic systems are the usual need of water as a coupling media and the high damping in thick walled or foamed pipes. For x-ray systems special safety requirements have to be taken into account because of the ionizing radiation. The terahertz (THz) technology offers a novel approach to solve these problems. THz waves have many properties which are suitable for the non-destructive testing of plastics. The absorption of electrical isolators is typically very low and the radiation is non-ionizing in comparison to x-rays. Through the electromagnetic origin of the THz waves they can be used for contact free measurements. Foams show a much lower absorption in contrast to acoustic waves. The developed system uses THz pulses which are generated by stimulating photoconductive switches with femtosecond laser pulses. The time of flight of THz pulses can be determined with a resolution in the magnitude of several ten femtoseconds. Hence the thickness of an object like plastic pipes can be determined with a high accuracy by measuring the time delay between two reflections on materials interfaces e.g. at the pipe's inner and outer surface, similar to the ultrasonic technique. Knowing the refractive index of the sample the absolute layer thickness from the transit time difference can be calculated easily. This method in principle also allows the measurement of multilayer systems and the characterization of foamed pipes.

  9. Thick de Sitter brane solutions in higher dimensions

    SciTech Connect (OSTI)

    Dzhunushaliev, Vladimir [Arnold-Sommerfeld-Center for Theoretical Physics, Department fuer Physik, Ludwig-Maximilians-Universitaet, Theresienstr. 37, D-80333, Munich (Germany); Department of Physics and Microelectronic Engineering, Kyrgyz-Russian Slavic University, Bishkek, Kievskaya Str. 44, 720021, Kyrgyz Republic (Russian Federation); Folomeev, Vladimir [Institute of Physics of National Academy of Science Kyrgyz Republic, 265 a, Chui Street, Bishkek, 720071 (Kyrgyzstan); Minamitsuji, Masato [Arnold-Sommerfeld-Center for Theoretical Physics, Department fuer Physik, Ludwig-Maximilians-Universitaet, Theresienstr. 37, D-80333, Munich (Germany); Center for Quantum Spacetime, Sogang University, Shinsu-dong 1, Mapo-gu, 121-742 Seoul (Korea, Republic of)

    2009-01-15T23:59:59.000Z

    We present thick de Sitter brane solutions which are supported by two interacting phantom scalar fields in five-, six-, and seven-dimensional spacetime. It is shown that for all cases regular solutions with anti-de Sitter asymptotic (5D problem) and a flat asymptotic far from the brane (6D and 7D cases) exist. We also discuss the stability of our solutions.

  10. Turbine blade having a constant thickness airfoil skin

    DOE Patents [OSTI]

    Marra, John J

    2012-10-23T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Quereda, J. [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049 (Spain); Castellanos-Gomez, A. [Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Agraït, N. [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049 (Spain); Instituto Madrileño de Estudios Avanzados en Nanociencia, IMDEA-Nanociencia, E-28049 Madrid (Spain); Instituto de Ciencia de Materiales Nicolás Cabrera, Campus de Cantoblanco, E-28049 Madrid (Spain); Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid (Spain); Rubio-Bollinger, G., E-mail: gabino.rubio@uam.es [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049 (Spain); Instituto de Ciencia de Materiales Nicolás Cabrera, Campus de Cantoblanco, E-28049 Madrid (Spain); Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid (Spain)

    2014-08-04T23:59:59.000Z

    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.

  12. A New Multi-Gaussian Auto-Correlation Function for the Modeling of Realistic Shot Peened Random Rough Surfaces

    SciTech Connect (OSTI)

    Hassan, W. [Honeywell Aerospace, 111 S. 34th Street, M/S 503-118 Phoenix, AZ 85034 (United States); Blodgett, M. [Air Force Research Laboratory (AFRL/MLLP), 2230 10th Street, Suite 1, Dayton, OH 45433 (United States)

    2006-03-06T23:59:59.000Z

    Shot peening is the primary surface treatment used to create a uniform, consistent, and reliable sub-surface compressive residual stress layer in aero engine components. A by-product of the shot peening process is random surface roughness that can affect the measurements of the resulting residual stresses and therefore impede their NDE assessment. High frequency eddy current conductivity measurements have the potential to assess these residual stresses in Ni-base super alloys. However, the effect of random surface roughness is expected to become significant in the desired measurement frequency range of 10 to 100 MHz. In this paper, a new Multi-Gaussian (MG) auto-correlation function is proposed for modeling the resulting pseudo-random rough profiles. Its use in the calculation of the Apparent Eddy Current Conductivity (AECC) loss due to surface roughness is demonstrated. The numerical results presented need to be validated with experimental measurements.

  13. Turbulent Friction in Rough Pipes and the Energy Spectrum of the Phenomenological Theory

    E-Print Network [OSTI]

    G. Gioia; Pinaki Chakraborty

    2005-12-20T23:59:59.000Z

    The classical experiments on turbulent friction in rough pipes were performed by J. Nikuradse in the 1930's. Seventy years later, they continue to defy theory. Here we model Nikuradse's experiments using the phenomenological theory of Kolmog\\'orov, a theory that is widely thought to be applicable only to highly idealized flows. Our results include both the empirical scalings of Blasius and Strickler, and are otherwise in minute qualitative agreement with the experiments; they suggest that the phenomenological theory may be relevant to other flows of practical interest; and they unveil the existence of close ties between two milestones of experimental and theoretical turbulence.

  14. Investigation of wall friction in noncircular ducts with a rough liner

    E-Print Network [OSTI]

    Tyler, John Charles

    1959-01-01T23:59:59.000Z

    section Density Viscosity Dimensions L5/Q L/Q m/L& m/LQ 1. The friction factors, Reynolds numbers, and. abso- lute roughnesses for fluid flow in ducts having a glass fiber liner have been calculated and plotted in the form of characteristic... distributed, it is essential that the wall friction phenomena associated with the particular duct design be understood. When fluid is passed through a duct, a static pressure drop occurs due to the friction forces which act between the fluid. particles...

  15. Ant Colony Optimization of Rough Set for HV Bushings Fault Detection

    E-Print Network [OSTI]

    Mpanza, J L

    2011-01-01T23:59:59.000Z

    Most transformer failures are attributed to bushings failures. Hence it is necessary to monitor the condition of bushings. In this paper three methods are developed to monitor the condition of oil filled bushing. Multi-layer perceptron (MLP), Radial basis function (RBF) and Rough Set (RS) models are developed and combined through majority voting to form a committee. The MLP performs better that the RBF and the RS is terms of classification accuracy. The RBF is the fasted to train. The committee performs better than the individual models. The diversity of models is measured to evaluate their similarity when used in the committee.

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

    E-Print Network [OSTI]

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

    2000-06-13T23:59:59.000Z

    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. A comparison of thick film and thin film traffic stripes

    E-Print Network [OSTI]

    Keese, Charles J

    1952-01-01T23:59:59.000Z

    Striys. . . Pigmented Bitusmn Stripes . Asphalt %uilt-Upa Striye vith Pigmented Portland Cement Mortar Cover Course 38 . ~ 41 Thin Film Stripes Used for Comparison Results of Comparing Thick Film Stripes and Thin Film Paint Stripes . ~ ~ ~ ~ ~ 43... was aspbaltio oonorets. The pavement in Test Areas 2y 3p and 4 vas portland cesmnh ooncrete, Two test areas (3 and 4) vere located in such manner as to provide uninterrupted flow of traffic over tbs entire length of the test area. The other two test areas (1...

  18. The fragmentation of expanding shells II: Thickness matters

    E-Print Network [OSTI]

    Wunsch, Richard; Palous, Jan; Whitworth, Anthony P

    2010-01-01T23:59:59.000Z

    We study analytically the development of gravitational instability in an expanding shell having finite thickness. We consider three models for the radial density profile of the shell: (i) an analytic uniform-density model, (ii) a semi-analytic model obtained by numerical solution of the hydrostatic equilibrium equation, and (iii) a 3D hydrodynamic simulation. We show that all three profiles are in close agreement, and this allows us to use the first model to describe fragments in the radial direction of the shell. We then use non-linear equations describing the time-evolution of a uniform oblate spheroid to derive the growth rates of shell fragments having different sizes. This yields a dispersion relation which depends on the shell thickness, and hence on the pressure confining the shell. We compare this dispersion relation with the dispersion relation obtained using the standard thin-shell analysis, and show that, if the confining pressure is low, only large fragments are unstable. On the other hand, if the...

  19. Oscillations of Thick Accretion Discs Around Black Holes - II

    E-Print Network [OSTI]

    Eduardo Rubio-Herrera; William H. Lee

    2005-05-21T23:59:59.000Z

    We present a numerical study of the global modes of oscillation of thick accretion discs around black holes. We have previously studied the case of constant distributions of specific angular momentum. In this second paper, we investigate (i) how the size of the disc affects the oscillation eigenfrequencies, and (ii) the effect of power-law distributions of angular momentum on the oscillations. In particular, we compare the oscillations of the disc with the epicyclic eigenfrequencies of a test particle with different angular momentum distributions orbiting around the central object. We find that there is a frequency shift away from the epicyclic eigenfrequency of the test particle to lower values as the size of the tori is increased. We have also studied the response of a thick accretion disc to a localized external perturbation using non constant specific angular momentum distributions within the disc. We find that in this case it is also possible (as reported previously for constant angular momentum distributions) to efficiently excite internal modes of oscillation. In fact we show here that the local perturbations excite global oscillations (acoustic p modes) closely related to the epicyclic oscillations of test particles. Our results are particularly relevant in the context of low mass X-ray binaries and microquasars, and the high frequency Quasi-Periodic Oscillations (QPOs) observed in them. Our computations make use of a Smooth Particle Hydrodynamics (SPH) code in azimuthal symmetry, and use a gravitational potential that mimics the effects of strong gravity.

  20. 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.

    1992-04-15T23:59:59.000Z

    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.

  1. Certain basic surgical principles of full-thickness free skin grafts in the dog

    E-Print Network [OSTI]

    Trevino, Gilberto Stephenson

    1959-01-01T23:59:59.000Z

    THICK GRAFT FULL THICKNESS GRAFT DERMIS ~i-/) HYPODERMIS 8 grafts 1n use todayo, . = - - Co HISTOHI QP SKIE GBAPTINQ ?' Hux earliest efforts to utilize skin for the reparation of integu- mentary defects vere undertalaen centuries ago...

  2. 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

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

    DOE Patents [OSTI]

    Yang, Fan (Piscataway, NJ); Forrest, Stephen R. (Ann Arbor, MI)

    2011-06-07T23:59:59.000Z

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

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

    DOE Patents [OSTI]

    Li, Ting (Ventura, CA)

    2011-04-26T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

    Li, Ting

    2013-08-13T23:59:59.000Z

    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.

  6. 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

    2009-10-06T23:59:59.000Z

    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.

  7. Ultrasonic thickness sampling plan for the depleted uranium hexafluoride program

    SciTech Connect (OSTI)

    Lyon, B.F.; Lykins, M.L.

    1996-07-01T23:59:59.000Z

    The United States Department of Energy (DOE) currently manages depleted uranium hexafluoride that is stored in approximately 50,000 carbon steel cylinders located at three DOE sites. The disposition of any particular cylinder for storage, handling, and transfer is based on the condition of the cylinder, where condition is ultimately reflected by the minimum wall thickness of a cylinder. Currently, the wall thickness of a cylinder may be measured using either a hand-held ultrasonic transducers or an automated scanner. At the Portsmouth site, the cylinder program is currently committed to a sampling plan that requires sampling 10% of the cylinders moved during the cylinder relocation efforts. The purpose of this report is to present a statistically-based sampling plan to be considered for use within the three site cylinder management program. This plan is designed to meet the following objectives: (1) allow determination of the current condition of the cylinder populations within the accuracy and confidence specified by cylinder program management, and (2) be sufficient for the models to be used for modeling purposes. The first objective does not require modeling in the sense of making assumptions about the corrosion process for the populations involved. By avoiding such additional assumptions, this may result in stronger statements to be made about the populations in question. Assumptions must be made regarding corrosion of the cylinders through time. The second objective depends on the particular model used. In this report, two basic methods are used in determining sample sizes. The sample sizes are intended to be conservative because it may be that other models are developed for use within the Program.

  8. Surface Roughness of Stainless Steel Bender Mirrors for FocusingSoft X-rays

    SciTech Connect (OSTI)

    Yashchuk, Valeriy V.; Gullikson, Eric M.; Howells, Malcolm R.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R.; Salmassi,Farhad; Warwick, Tony; Metz, James P.; Tonnessen, Thomas W.

    2005-10-11T23:59:59.000Z

    We have used polished stainless steel as a mirror substrate to provide focusing of soft x-rays in grazing incidence reflection. The substrate is bent to an elliptical shape with large curvature and high stresses in the substrate require a strong elastic material. Conventional material choices of silicon or of glass will not withstand the stress required. The use of steel allows the substrates to be polished and installed flat, using screws in tapped holes. The ultra-high-vacuum bender mechanism is motorized and computer controlled. These mirrors are used to deliver focused beams of soft x-rays onto the surface of a sample for experiments at the Advanced Light Source (ALS). They provide an illumination field that can be as small as the mirror demagnification allows, for localized study, and can be enlarged, under computer control,for survey measurements over areas of the surface up to several millimeters. The critical issue of the quality of the steel surface, polished and coated with gold, which limits the minimum achievable focused spot size is discussed in detail. Comparison is made to a polished, gold coated, electroless nickel surface, which provides a smoother finish. Surface measurements are presented as power spectral densities, as a function of spatial frequency. The surface height distributions measured with an interferometric microscope, and complemented by atomic force microscope measurements, are used to compute power spectral densities and then to evaluate the surface roughness. The effects of roughness in reducing the specular reflectivity are verified by soft x-ray measurements.

  9. 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)

    2014-11-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Shnapp, Ron

    2014-01-01T23:59:59.000Z

    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.

  11. EHL OIL FILM THICKNESS UNDER ROLLING-SLIDING CONTACT 2 W

    E-Print Network [OSTI]

    D. M. Nuruzzaman; M. A. A. Sheikh

    Oil film Abstract: The Elastohydrodynamic lubrication (EHL) minimum oil film thickness is theoretically investigated under rolling with sliding contact. The effects of contact pressure, rolling speed and slip ratio on the EHL minimum oil film thickness are calculated numerically. It is found that for a range of contact pressure from 0.5 to 3.5 GPa, the minimum oil film thickness gradually decreases with the increase in contact pressure. As the rolling speed increases from 3500 to 4500 rpm, oil film thickness is increased. It is also found that the oil film thickness is not much influenced by the slip ratio. 1

  12. Analyzing the thickness of a TEM sample using EELSAnalyzing the thickness of a TEM sample using EELS and integration techniquesand integration techniques

    E-Print Network [OSTI]

    Petta, Jason

    EELS and integration techniquesand integration techniques Antonio Buddington Imaging and Analysis film sample? Analyzing the thickness of a TEM sample using EELS and integration techniques #12;Method Analyzing the thickness of a TEM sample using EELS and integration techniques Specimen examined under

  13. 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)

    2003-12-23T23:59:59.000Z

    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.

  14. The impact of new short season rice varieties on drying and storage of rough rice in Texas

    E-Print Network [OSTI]

    Bhagia, Gobind Shewakram

    1967-01-01T23:59:59.000Z

    THE IMPACT OF NEW SHORT SEASON RICE VARIETIES ON DRYING AND STORAGE OF ROUGH RICE IN TEXAS A Thesis by GOBIND SHEWAKRAM BHAGIA Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE January 1967 Ma)or Sub/ect: Agricultural Economics THE IMPACT OF NEW SHORT SEASON RICE VARIETIES ON DRYING AND STORAGE OF ROUGH RICE IN TEXAS A Thesis by GOBIND SHEWAKIUiM BHAGIA Approved as to style and oontent by...

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

    SciTech Connect (OSTI)

    Not Available

    2013-11-01T23:59:59.000Z

    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.

  16. Lithium in very metal poor thick disk stars

    E-Print Network [OSTI]

    P. Molaro; P. Bonifacio; L. Pasquini

    1997-09-25T23:59:59.000Z

    A search for lithium is performed on seven metal poor dwarfs with metallicities ranging from [Fe/H]=-1.5 down to [Fe/H]=-3.0 but showing disk-like kinematics. These stars belong to the metal poor tail of the Galactic thick disk and they may be also the result of an accretion event (Beers and Sommer-Larsen 1995). The Li 6707.8 A line is present in all the seven dwarfs. The weighted average of the Li abundance for the stars is A(Li)=2.20 (+/-0.06) and is consistent within the errors with the plateau Li abundance of A(Li)=2.24(+/- 0.012) found in genuine halo stars in the same range of metallicities (Bonifacio and Molaro 1997). One of the stars, CS 22182-24, shows somewhat lower Li abundance (A(Li)=1.6(+/-0.40)) and is a candidate to being a Li-poor star. Whether this group of stars belongs to the oldest stars in the disk or to the old population of an external galaxy accreted by the Milky Way, the present observations provide support to the universality of a pre-Galactic Li abundance as is observed in the Galactic halo stars.

  17. Rotary union for use with ultrasonic thickness measuring probe

    DOE Patents [OSTI]

    Nachbar, H.D.

    1992-09-15T23:59:59.000Z

    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.

  18. Assessment of Nuclear Fuels using Radiographic Thickness Measurement Method

    SciTech Connect (OSTI)

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

    2014-11-01T23:59:59.000Z

    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.

  19. Properties of micrometer-thick plasma-polymerized tetrafluoroethylene films

    SciTech Connect (OSTI)

    Butler, M.A.; Buss, R.J.; Galuska, A. (Sandia National Laboratories, Albuquerque, New Mexico (USA))

    1991-08-15T23:59:59.000Z

    Several physical properties of thin plasma-polymerized films have been measured using a new fiber-optic-based technique. Films of plasma-polymerized tetrafluoroethylene (PPTFE) deposited on the end of an optical fiber form an optical cavity, the reflectivity of which is very sensitive to the film thickness. The fiber is used as an {ital in} {ital situ} monitor of the deposition rate in the plasma and, after removal from the plasma, the mechanical properties of the film can be measured. With this measurement technique the thermal expansion of the film normal to its surface as well as the swelling of the film when exposed to an array of organic solvents have been determined. A significantly smaller thermal-expansion coefficient and larger degree of swelling are observed relative to bulk PTFE. X-ray photoelectron spectroscopy measurements show that the fluorocarbon chains are highly branched and have a fluorine-to-carbon ratio of 1.45. These results suggest that the plasma-polymerized films are not crystalline and are heavily cross linked.

  20. In-flight Receptivity Experiments on a 30-degree Swept-wing using Micron-sized Discrete Roughness Elements

    E-Print Network [OSTI]

    Carpenter, Andrew L.

    2010-01-16T23:59:59.000Z

    and operated at a chord Reynolds number of 6.5 to 7.5 million. Spanwise-periodic, micronsized discrete roughness elements were applied at the leading edge of the swept-wing in order to excite the most unstable crossflow wavelength and promote early boundary...

  1. Impact of surface roughness of Au core in Au/Pd coreeshell nanoparticles toward formic acid oxidation e Experiment and

    E-Print Network [OSTI]

    Liu, Fuqiang

    Impact of surface roughness of Au core in Au/Pd coreeshell nanoparticles toward formic acid h t s Unique Au/Pd coreeshell nanoparticles were synthesized via a galvanic replacement of Cu by Pd on hollow Au. Au/Pd coreeshell nanoparticles with smooth Au surface by adding Na2SO3 demonstrated highly

  2. The Effect of Inner Surface Roughness on Friction Factor in Horizontal Micro-A. J. Ghajar1

    E-Print Network [OSTI]

    Ghajar, Afshin J.

    The Effect of Inner Surface Roughness on Friction Factor in Horizontal Micro- tubes A. J. Ghajar1 1 blood vessels, a sound understanding of fluid flow in micro- scale channels and tubes is required of the transition region. II. LITERATURE REVIEW To fully understand the flow phenomenon inside of micro-tubes

  3. Modeling, system identication, and control for dynamic locomotion of the LittleDog robot on rough terrain

    E-Print Network [OSTI]

    Levashov, Michael Yurievich

    2012-01-01T23:59:59.000Z

    In this thesis, I present a framework for achieving a stable bounding gait on the LittleDog robot over rough terrain. The framework relies on an accurate planar model of the dynamics, which I assembled from a model of the ...

  4. Polycrystal modelling of fatigue: pre-hardening and surface roughness effects on damage initiation for 304L stainless steel

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of residual heat removal circuits of pressurized water reactors (PWR).The main purpose of this study surface (pre- hardening gradient, residual stresses and scratches), at the scale of the microstructure properties (roughness, residual stress and pre-hardening) and to the microstructure of the material

  5. Linear Algebra Research Project Rough Draft Nick Davis Camera Transformations in OpenGL ES 2.0

    E-Print Network [OSTI]

    Marzuola, Jeremy

    Linear Algebra Research Project Rough Draft Nick Davis Camera Transformations in OpenGL ES 2.0 Since the advent of the analog computer the power of visual display has played an integral part graphical output, including components designed solely for calculating graphics (Graphics Processing Units

  6. 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-

    2012-12-10T23:59:59.000Z

    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...

  7. 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

    2009-10-19T23:59:59.000Z

    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.

  8. 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

  9. Thickness dependent functional properties of PbZr{sub 0.52}Ti{sub 0.48}O{sub 3}/La{sub 0.67}Sr{sub 0.33}MnO{sub 3} heterostructures

    SciTech Connect (OSTI)

    Barrionuevo, D.; Ortega, N.; Katiyar, R. S. [Department of Physics and Institute of Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); Kumar, A. [National Physical Laboratory (CSIR), Dr. K. S. Krishnan Road, New Delhi 110012 (India); Chatterjee, R. [Indian Institute of Technology, Hauz Khas, New Delhi (India); Scott, J. F. [Department of Physics and Institute of Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); Earth Science Department, University of Cambridge, Cambridge CB2 3EQ (United Kingdom)

    2013-12-21T23:59:59.000Z

    The ultra thin ferroelectric PbZr{sub 0.52}Ti{sub 0.48}O{sub 3} (PZT) films with various thicknesses ranging from 100 (P100) to 10 (P10) nm were grown on La{sub 0.67}Sr{sub 0.33}MnO{sub 3}/(LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} (LSMO/LSAT) (001) substrates deposited by pulsed laser deposition technique. The x-ray diffraction patterns of the heterostructures show only (00l) (l?=?1 and/or 2) reflections corresponding to the LSAT substrate, PZT, and LSMO layers. The atomic force microscopy studies show that the root mean square surface roughnesses of P100 and P10 films are 2.39 and 0.99?nm, respectively. An increase of both real (??) and imaginary (??) permittivities was observed when thickness of PZT increases from 10?nm to 100?nm. Temperature dependent ?? presents an anomaly, related to ferromagnetic-metal to paramagnetic-insulator transition of the LSMO, in the range of 350–500?K. The dielectric anomalies and magnetic phase transition temperature shifted to the lower temperature values with decrease in the PZT films thicknesses. The values of the remanent polarization (P{sub r}) and coercive field (E{sub c}) of the heterostructures were in the range of 24–42??C/cm{sup 2}–170–1300?kV/cm. An appreciable increase of saturated magnetization (M{sub s}) was observed with increase of PZT layer thickness. The average M{sub s} values of PZT/LSMO heterostructure were 170, 150, 100, and 45?emu/cm{sup 3} for 100, 50, 25, and 10?nm at 300?K, respectively. Enhancement in magnetization with increase in PZT thickness may be due to the interface effect between PZT/LSMO layers.

  10. 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.

    2014-11-01T23:59:59.000Z

    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.

  11. Systematic analysis of Persson's contact mechanics theory of randomly rough elastic surfaces

    E-Print Network [OSTI]

    Wolf B. Dapp; Nikolay Prodanov; Martin H. Müser

    2014-06-24T23:59:59.000Z

    We systematically check explicit and implicit assumptions of Persson's contact mechanics theory. It casts the evolution of the pressure distribution ${\\rm Pr}(p)$ with increasing resolution of surface roughness as a diffusive process, in which resolution plays the role of time. The tested key assumptions of the theory are: (a) the diffusion coefficient is independent of pressure $p$, (b) the diffusion process is drift-free at any value of $p$, (c) the point $p=0$ acts as an absorbing barrier, i.e., once a point falls out of contact, it never reenters again, (d) the Fourier component of the elastic energy is only populated if the appropriate wave vector is resolved, and (e) it no longer changes when even smaller wavelengths are resolved. Using high-resolution numerical simulations, we quantify deviations from these approximations and find quite significant discrepancies in some cases. For example, the drift becomes substantial for small values of $p$, which typically represent points in real space close to a contact line. On the other hand, there is a significant flux of points reentering contact. These and other identified deviations cancel each other to a large degree, resulting in an overall excellent description for contact area, contact geometry, and gap distribution functions. Similar fortuitous error cancellations cannot be guaranteed under different circumstances, for instance when investigating rubber friction. The results of the simulations may provide guidelines for a systematic improvement of the theory.

  12. 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)

    2014-01-29T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    Subglacial topography inferred from ice surface ter- rainSubglacial topography inferred from ice surface ter- rainsurface eleva- tion, ice thickness and subglacial topography

  14. Coating thickness measurement by XRF in vacuum strip steel metallizing plants

    SciTech Connect (OSTI)

    Wenzel, D. [Von Ardenne Anlagentechnik GmbH, Dresden (Germany); Esche, H.J.; Pilz, J. [Amtec AnalysenmeBtechnik GmbH, Leipzig (Germany)

    1994-12-31T23:59:59.000Z

    Devised for use in vacuum equipment of PVD strip steel coaters is a multichannel counting technique for the continuous XRF measurement of the coating thickness. This XRF coating thickness gage is used in a batch-type strip steel coater. It measures the thickness of single-side, double-side and alloy coatings (element contents included). The new XRF method operates without etalons. It is also possible to measure adjacent elements in the periodic law of chemical elements without difficulty. With only minor deviations from the nominal value the new XRF measuring system allows to keep the coating thickness practically constant.

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

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    Antarctica (MOA) image map: Digital media, National Snow andmodel of Antarctica: Digital media, National Snow and IceThickness, 2009–2011: Digital media, NASA Distributed Active

  16. Colloid deposition on non-ideal porous media: The influences of collector shape and roughness on the single-collector efficiency

    E-Print Network [OSTI]

    Saiers, James

    Colloid deposition on non-ideal porous media: The influences of collector shape and roughness on the single-collector efficiency James E. Saiers School of Environmental Studies, Yale University, New Haven changes in mineral-grain shape and surface roughness influence the single-collector contact efficiency (h

  17. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 40, NO. 7, JULY 2002 1605 Surface Roughness Characterizations of Sea Ice and

    E-Print Network [OSTI]

    Kurapov, Alexander

    , surface roughness data from airborne laser altimeter transects correlate well with MISR-derived estimates of surface roughness. In Antarctica, ablation-related blue-ice areas, which are difficult to distinguish from bare ice exposed by crevasses, are easily detected using multiangular data. These unusual ablation

  18. Distribution of germanium in Si{sub 1-x}Ge{sub x} (x < 0.1) layers grown on the Si(001) substrate as a function of layer thickness

    SciTech Connect (OSTI)

    Bagaev, V. S.; Krivobok, V. S.; Martovitsky, V. P., E-mail: victormart@yandex.r [Russian Academy of Sciences, P. N. Lebedev Physical Institute (Russian Federation); Novikov, A. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2009-12-15T23:59:59.000Z

    The germanium distribution in Si(001)/Si{sub 1-x}Ge{sub x} layers as a function of the layer thickness at a low dopant concentration (x < 6%) has been investigated using high-resolution X-ray diffractometry and low-temperature photoluminescence. It has been shown that the germanium concentration increases with increasing thickness of the SiGe layer with the formation of lateral inhomogeneities at the boundary between this layer and a silicon cap layer for a layer thickness of 30 nm or more. These inhomogeneities have an oriented character and give rise to anisotropic diffuse scattering for the system of (113) and (224) asymmetric reflections from SiGe. The luminescence of these films at low temperatures and low excitation densities is an emission of localized and delocalized excitons, which is characteristic of systems with disorder. The revealed nonuniform germanium distribution in the lateral direction is associated with the accumulation of germanium in the near-surface SiGe layer and with the partial relaxation of elastic strains due to the development of surface roughness and the preferred incorporation of germanium atoms into one side of the surface ripples.

  19. 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

  20. Channel and wedge plasmon modes of metallic V-grooves with finite metal thickness

    E-Print Network [OSTI]

    Floreano, Dario

    Channel and wedge plasmon modes of metallic V-grooves with finite metal thickness José Dintinger thickness on the propagation characteristics of the channel plasmon polariton (CPP) and wedge plasmon is found to evolve into short range plasmon modes propagating along the groove walls, in contrast

  1. 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. [Departament d'Estructura i Conastituents de la Materia and Institut de Ciencies del Cosmos, Facultat de Fisica, Universitat de Barcelona, Marti i Franques 1, 08028, Barcelona (Spain); Instituto Nazionale di Fisica Nucleare, Sezione di Milano , Via Celoria 16, I-20133 Milano (Italy); Katedra Fizyki Teoretycznej, Uniwersytet Marii Curie-Skodowskiej ul. Radziszewskiego 10, 20-031 Lublin (Poland)

    2012-10-20T23:59:59.000Z

    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.

  2. FLUORESCENCE AND FIBER-OPTICS BASED REAL-TIME THICKNESS SENSOR FOR DYNAMIC LIQUID FILMS

    E-Print Network [OSTI]

    Narain, Amitabh

    /analyzed the incident reflected waves to identify and measure the total transit time of the sound wave (of known wave-speed1 FLUORESCENCE AND FIBER-OPTICS BASED REAL-TIME THICKNESS SENSOR FOR DYNAMIC LIQUID FILMS T. W. Ng/disadvantages of many known liquid film thickness sensing devices (viz. conductivity probes, reflectance based fiber

  3. Sea-ice thickness measurement based on the dispersion of ice swell

    E-Print Network [OSTI]

    -year pack ice, although other char- acteristics (Young's modulus, shear modulus, and Poisson coefficientSea-ice thickness measurement based on the dispersion of ice swell David Marsana) ISTerre, CNRS propagating in the Arctic sea ice cover is exploited in order to locally measure the ice thickness

  4. SAR Motion Products: Tools for Monitoring Changes in Sea Ice Mass Balance and Thickness Distribution

    E-Print Network [OSTI]

    Geiger, Cathleen

    decrease in a warming climate. For example, in a weakening ice pack, we could expect convergence storminess in the Arctic; (b) a seasonal ice pack of reduced thickness; and (c) large scale changes in driftSAR Motion Products: Tools for Monitoring Changes in Sea Ice Mass Balance and Thickness

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

    E-Print Network [OSTI]

    Zhang, Jinlun

    of fast ice formation and growth. Instead, the modeled fast ice is replaced with pack ice which driftsEvaluation of Arctic sea ice thickness simulated by Arctic Ocean Model Intercomparison Project with estimates of sea ice thickness derived from pan-Arctic satellite freeboard measurements (2004

  6. On the effective plate thickness of monolayer graphene from flexural wave propagation

    E-Print Network [OSTI]

    Lin, Xi

    On the effective plate thickness of monolayer graphene from flexural wave propagation Sung Youb Kim utilize classical molecular dynamics to study flexural, or transverse wave propagation in monolayer) mode of wave propagation in a thin plate with plate thickness of h ¼ 0:104 nm. Finally, we find

  7. Reactivity of a Thick BaO Film Supported on Pt(111): Adsorption...

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

    a Thick BaO Film Supported on Pt(111): Adsorption and Reaction of NO2, H2O and CO2. Reactivity of a Thick BaO Film Supported on Pt(111): Adsorption and Reaction of NO2, H2O and...

  8. Great Lakes Ice Thickness Data Rescue Primary Investigator: Raymond Assel -NOAA/GLERL (Emeritus)

    E-Print Network [OSTI]

    Great Lakes Ice Thickness Data Rescue Primary Investigator: Raymond Assel - NOAA/GLERL (Emeritus) Overview Ice cover is an important environmental factor affecting physical and biological processes in the coastal region of the Great Lakes. However, computerized ice thickness data along the shores of the Great

  9. MCM LTER METADATA FILE TITLE: Lake ice thickness in the McMurdo Dry Valleys

    E-Print Network [OSTI]

    Priscu, John C.

    MCM LTER METADATA FILE TITLE: Lake ice thickness in the McMurdo Dry Valleys ABSTRACT: Ice thickness was measured from the bottom of the ice cover to the piezometric water level and to the top of the ice cover-2360 achiuchiolo@montana.edu VARIABLES: Location Name, Location Code, Limno Run, Collection Date, z-water, z-ice, z

  10. 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

  11. 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

  12. Ice Mass Balance Buoy: An Instrument to Measure and Attribute Changes in Ice Thickness

    E-Print Network [OSTI]

    Geiger, Cathleen

    Ice Mass Balance Buoy: An Instrument to Measure and Attribute Changes in Ice Thickness Jacqueline A the Ice Mass Balance buoy (IMB) in response to the need for monitoring changes in the thickness of the Arctic sea ice cover. The IMB is an autonomous, ice-based system. IMB buoys provide a time series of ice

  13. 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

  14. High-resolution estimates of lithospheric thickness from Missouri to Massachusetts, USA

    E-Print Network [OSTI]

    van der Lee, Suzan

    -dimensional (3-D) model, NA00, of the S-velocity of the upper mantle beneath North America. The model differs. The seismic lithosphere is 180 km thick below Missouri and Illinois, 200 km thick below Indiana, Ohio by fitting the waveforms of broadband seismic S and surface waves recorded by the MOMA array and inverting

  15. Seismic evidence for a moderately thick lithosphere beneath the Siberian Platform

    E-Print Network [OSTI]

    Seismic evidence for a moderately thick lithosphere beneath the Siberian Platform Keith Priestley-wavespeed tomographic model for the upper mantle beneath the Siberian platform and surrounding region derived from lithosphere is $200 km thick beneath most of the Siberian platform but may extend to $250 km depth beneath

  16. Atomic intermixing and interface roughness in short-period InAs/GaSb superlattices for infrared photodetectors

    SciTech Connect (OSTI)

    Ashuach, Y.; Lakin, E.; Kaufmann, Y. [Department of Materials Science and Engineering, Technion—Israel Institute of Technology, Haifa 32000 (Israel); Saguy, C. [Solid State Institute, Technion—Israel Institute of Technology, Haifa 32000 (Israel); Zolotoyabko, E., E-mail: zloto@tx.technion.ac.il [Department of Materials Science and Engineering, Technion—Israel Institute of Technology, Haifa 32000 (Israel); Solid State Institute, Technion—Israel Institute of Technology, Haifa 32000 (Israel)

    2014-09-28T23:59:59.000Z

    A set of advanced characterization methods, including high-resolution X-ray diffraction (measurements and simulations), cross-sectional scanning tunneling microscopy, and high-angle annular dark-field scanning transmission electron microscopy is applied to quantify the interface roughness and atomic intermixing (in both cation and anion sub-lattices) in short period (6–7?nm) InAs/GaSb superlattices intended for mid-wavelength (M) and long-wavelength (L) infrared detectors. The undesired atomic intermixing and interface roughness in the L-samples were found to be considerably lower than in the M-samples. In all specimens, anion intermixing is much higher than that in the cation sub-lattice. Possible origins of these findings are discussed.

  17. An experimental investigation of silicon wafer surface roughness and its effect on the full strength of plated metals

    SciTech Connect (OSTI)

    Spiers, G.D.

    1981-01-01T23:59:59.000Z

    Plated silicon wafers with surface roughness ranging from 0.4 to 130 microinches were subjected to tensile pull strength tests. Electroless Ni/electroless Cu/electroplated Cu and electroless Ni/electroplated Cu were the two types of plate contacts tested. It was found that smoother surfaces had higher pull strength than rougher, chemically etched surfaces. The presence of the electroless Cu layer was found to be important to adhesion. The mode of fracture of the contact as it left the silicon was studied, and it was found that in almost all cases separation was due to fracture of the bulk silicon phase. The correlation between surface roughness and mode of contact failure is presented and interpreted.

  18. Development of the Robotic Touch foot Sensor for 2D walking Robot, for Studying Rough Terrain Locomotion

    E-Print Network [OSTI]

    Lee, Hunwoo

    2012-08-31T23:59:59.000Z

    Development of the Robotic Touch foot Sensor for 2D walking Robot, for Studying Rough Terrain Locomotion By HUNWOO LEE Submitted to the graduate degree program in Mechanical Engineering and the Graduate Faculty of the University of Kansas... ________________________________ Professor Robert Umholtz Date Defended: June 5, 2012 ii The Thesis Committee for HUNWOO LEE certifies that this is the approved version of the following thesis: Development of the Robotic Touch Foot Sensor for 2D Walking Robot...

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

    E-Print Network [OSTI]

    Rutenberg, Andrew

    Roughness with In Situ Atomic Force Microscopy L.Y. Beaulieu,1 A.D. Rutenberg,1 and J.R. Dahn1,2 * 1 Physics on Received May 23, 2001; accepted October 15, 2001. *Corresponding author. E-mail: jeff.dahn@dal.ca Microsc

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

    SciTech Connect (OSTI)

    Mueller, D., E-mail: dmueller@pppl.gov; Roquemore, A. L.; Jaworski, M.; Skinner, C. H.; Miller, J.; Creely, A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Raman, P.; Ruzic, D. [Department of Nuclear, Plasma, and Radiological Engineering, Center for Plasma Material Interaction, University of Illinois, Urbana, Illinois 61801 (United States)

    2014-11-15T23:59:59.000Z

    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.

  1. 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)

    2010-02-22T23:59:59.000Z

    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.

  2. 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)

    2011-09-01T23:59:59.000Z

    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.

  3. Separate effects of surface roughness, wettability and porosity on boiling heat transfer and critical heat flux and optimization of boiling surfaces

    E-Print Network [OSTI]

    O'Hanley, Harrison Fagan

    2012-01-01T23:59:59.000Z

    The separate effects of surface wettability, porosity, and roughness on critical heat flux (CHF) and heat transfer coefficient (HTC) were examined using carefully-engineered surfaces. All test surfaces were prepared on ...

  4. Leukemia Prediction from Gene Expression Data---A Rough Set Approach Jianwen Fang, Jerzy W. Grzymala-Busse, Information and Telecommunication

    E-Print Network [OSTI]

    Kansas, University of

    . Grzymala-Busse, Information and Telecommunication Technology Center, University of Kansas, Lawrence, KS Data---A Rough Set Approach Jianwen Fang1,2 and Jerzy W. Grzymala-Busse1,3 1Bioinformatics Core

  5. Reaction of NO2 with a pure, thick BaO film: the effect of temperature...

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

    film: the effect of temperature on the nature of NOx species formed. Abstract: The adsorption and reaction of NO2 on a thick (>30 ML), pure BaO film deposited onto an Al2O3...

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

    E-Print Network [OSTI]

    Morgan, Benjamin Patrick

    2012-10-19T23:59:59.000Z

    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...

  7. Maritime aerosol optical thickness measured by handheld sun photometers Kirk D. Knobelspiessea,b

    E-Print Network [OSTI]

    thickness (AOT) and 2ngstrfm exponent reveal varied aerosol populations. A K-means unsupervised Sensor Inter-comparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project

  8. Influence of magnetic electrodes thicknesses on the transport properties of magnetic tunnel junctions with perpendicular anisotropy

    SciTech Connect (OSTI)

    Cuchet, Léa; Rodmacq, Bernard; Auffret, Stéphane; Sousa, Ricardo C.; Dieny, Bernard [SPINTEC, UMR 8191, CEA-INAC/CNRS/UJF-Grenoble 1/Grenoble-INP, 38054 Grenoble Cedex (France)

    2014-08-04T23:59:59.000Z

    The influence of the bottom and top magnetic electrodes thicknesses on both perpendicular anisotropy and transport properties is studied in (Co/Pt)/Ta/CoFeB/MgO/FeCoB/Ta magnetic tunnel junctions. By carefully investigating the relative magnetic moment of the two electrodes as a function of their thicknesses, we identify and quantify the presence of magnetically dead layers, likely localized at the interfaces with Ta, that is, 0.33?nm for the bottom electrode and 0.60?nm for the top one. Critical thicknesses (spin-reorientation transitions) are determined as 1.60 and 1.65?nm for bottom and top electrodes, respectively. The tunnel magnetoresistance ratio reaches its maximum value, as soon as both effective (corrected from dead layer) electrode thicknesses exceed 0.6?nm.

  9. Enhanced radiation tolerance in nitride multilayered nanofilms with small period-thicknesses

    SciTech Connect (OSTI)

    Hong Mengqing; Ren Feng; Zhang Hongxiu; Xiao Xiangheng; Tian Canxin; Fu Dejun; Jiang Changzhong [School of Physics and Technology and Center for Electron Microscopy, Wuhan University, Wuhan 430072 (China); Yang Bing [School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072 (China); Wang Yongqiang [Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2012-10-08T23:59:59.000Z

    This paper demonstrates a substantial enhancement in radiation tolerance for small period-thickness of CrN/AlTiN multilayered nanofilms. CrN/AlTiN multilayered nanofilms with period-thicknesses of 3, 5, 7, and 9 nm were irradiated by 190 keV Ar{sup +} ions to fluences ranging from 1 to 5 Multiplication-Sign 10{sup 16} ions/cm{sup 2}. Nanofilm with 3 nm period-thickness begins to be amorphized under 5 Multiplication-Sign 10{sup 16} ions/cm{sup 2}, while those with larger period-thicknesses are amorphized under 3 Multiplication-Sign 10{sup 16} ions/cm{sup 2}. Our results show that multilayered ceramic nanofilms are potential radiation tolerant materials with good properties. The interfaces in the multilayered nanofilms act as good sinks to absorb the radiation-induced defects.

  10. 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 ...

  11. Measuring Tail Thickness under GARCH and an Application to Extremal Exchange Rate Changes

    E-Print Network [OSTI]

    Wagner, Niklas; Marsh, Terry A.

    2003-01-01T23:59:59.000Z

    relations and Extremes of a GARCH(1,1) Process, Annals ofMeasuring Tail Thickness under GARCH And an Application todistribution functions including GARCH and propose a model-

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

    E-Print Network [OSTI]

    Turkewitz, Jared Ripley

    2010-01-01T23:59:59.000Z

    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 ...

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

    E-Print Network [OSTI]

    Xu, Ben

    2011-08-08T23:59:59.000Z

    . 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...

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

    E-Print Network [OSTI]

    Xu, Ben

    2011-08-08T23:59:59.000Z

    . 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...

  15. 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))

    1992-01-01T23:59:59.000Z

    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.

  16. Thick and Thin Film Polymer CNT Nanocomposites for Thermoelectric Energy Conversion and Transparent Electrodes

    E-Print Network [OSTI]

    Fisher, Frank

    Thick and Thin Film Polymer ­ CNT Nanocomposites for Thermoelectric Energy Conversion gradient. Thermoelectric materials harvest electricity from waste heat or any temperature gradient]. The PDDA/(SWNT+DOC) system produced transparent (> 82% visible light transmittance) and electrically

  17. Evaluation of discontinuity stresses in thick walled cylindrical shells by means of an embedded polariscope

    E-Print Network [OSTI]

    Cano, Narciso Ortiz

    1968-01-01T23:59:59.000Z

    EVALUATION OF DISCONTINUITY STRESSES IN THICK WALLED CYLINDRICAL SHELLS BY MEANS OF AN EMBEDDED POLARISCOPE A Thesis By NARCISO ORTIZ CANO, JR. Submitted to the Graduate College of the Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE January, 196B Major Sub)ect: Aerospace Engineering EVALUATION OF DISCONTINUITY STRESSES IN THICK WALLED CYLINDRICAL SHELLS BY MEANS OF AN EMBEDDED POLARISCOPE A Thesis By NARCISO ORTIZ CANO, JR. Approved...

  18. Thickness estimation of subsurface layers in asphalt pavement using monstatic ground penetrating radar

    E-Print Network [OSTI]

    Lau, Chun Lok

    1991-01-01T23:59:59.000Z

    for the degree of MASTER OF SCIENCE December 1991 Major Subject: Electrical Engineering THICKNESS ESTIMATION OF SUBSURFACE LAYERS IN ASPHALT PAVEMENT USING MONSTATIC GROUND PENETRATING RADAR A Thesis CHUN LOK LAU Approved as to style and content by... ACKNOWLEDGEMENTS. LIST OF FIGURES. . CHAPTER I INTRODUCTION. 1. 1 Importance of pavement profile data. 1. 2 Principle of Ground Penetrating Radar (GPR) . . . 1. 3 Subsurface layer thickness measurement method. . . . . . II GPR ANTENNA AND SYSTEM CALIBRATION...

  19. Infrared Transmissometer to Measure the Thickness of NbN Thin Films

    E-Print Network [OSTI]

    Sunter, Kristen A; Lang, Christopher I; Berggren, Karl K

    2015-01-01T23:59:59.000Z

    We present an optical setup that can be used to characterize the thicknesses of thin NbN films to screen samples for fabrication and to better model the performance of the resulting superconducting nanowire single photon detectors. The infrared transmissometer reported here is easy to use, gives results within minutes and is non-destructive. Thus, the thickness measurement can be easily integrated into the workflow of deposition and characterization. Comparison to a similar visible-wavelength transmissometer is provided.

  20. The effect of stratum thickness ratio on crossflow in a stratified petroleum reservoir 

    E-Print Network [OSTI]

    Kereluk, Michael Joseph

    1966-01-01T23:59:59.000Z

    THE EFFECT OF STRATUM THICKNESS RATIO ON CROSSFLOW IN A STRATIFIED PETROLEUM RESERVOIR A Thesis By Michael J. Kereluk Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE May 4966 Major Subject: Petroleum Engineering THE EFFECT OF STRATUM THICKNESS RATIO ON CROSSFLOW IN A STRATIFIED PETROLEUM RESERVOIR A Thesis By Michael I. Kereluk Approved as to style and content by: Chazrma of Com 'ttee...

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

    E-Print Network [OSTI]

    Bacham E. Reddy; David L. Lambert

    2008-09-05T23:59:59.000Z

    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.

  2. Roughness analysis applied to niobium thin films grown on MgO(001) surfaces for superconducting radio frequency cavity applications

    SciTech Connect (OSTI)

    D. B. Beringer, W. M. Roach, C. Clavero, C. E. Reece, R. A. Lukaszew

    2013-02-01T23:59:59.000Z

    This paper describes surface studies to address roughness issues inherent to thin film coatings deposited onto superconducting radio frequency (SRF) cavities. This is particularly relevant for multilayered thin film coatings that are being considered as a possible scheme to overcome technical issues and to surpass the fundamental limit of ?50??MV/m accelerating gradient achievable with bulk niobium. In 2006, a model by Gurevich [ Appl. Phys. Lett. 88 012511 (2006)] was proposed to overcome this limit that involves coating superconducting layers separated by insulating ones onto the inner walls of the cavities. Thus, we have undertaken a systematic effort to understand the dynamic evolution of the Nb surface under specific deposition thin film conditions onto an insulating surface in order to explore the feasibility of the proposed model. We examine and compare the morphology from two distinct Nb/MgO series, each with its own epitaxial registry, at very low growth rates and closely examine the dynamical scaling of the surface features during growth. Further, we apply analysis techniques such as power spectral density to the specific problem of thin film growth and roughness evolution to qualify the set of deposition conditions that lead to successful SRF coatings.

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

    E-Print Network [OSTI]

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

    2005-03-13T23:59:59.000Z

    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.

  4. 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)

    2002-01-01T23:59:59.000Z

    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.

  5. 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)

    2001-01-01T23:59:59.000Z

    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.

  6. Extraplanar Dust: a Tracer of Cold Dense Gas in the Thick Disks of Spiral Galaxies

    E-Print Network [OSTI]

    J. Christopher Howk

    2004-10-15T23:59:59.000Z

    The interstellar thick disks of galaxies contain not only gas, but significant quantities of dust. Most of our knowledge of extraplanar dust in disk galaxies comes from direct broadband optical imaging of these systems, wherein the dust is identified due to the irregular extinction it produces against the thick disk and bulge stars. This observational technique is sensitive to only the most dense material, and we argue much of the material identified in this way traces a cold phase of the interstellar thick disks in galaxies. The presence of a cold, dense phase likely implies the interstellar pressures in the thick disks of spiral galaxies can be quite high. This dense phase of the interstellar medium may also fueling thick disk star formation, and H-alpha observations are now revealing H II regions around newly-formed OB stars associations in several galaxies. We argue that the large quantities of dust and the morphologies of the structures traced by the dust imply that much of the extraplanar material in disk galaxies must have been expelled from the underlying thin disk.

  7. 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)

    2015-01-07T23:59:59.000Z

    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.

  8. Cosmic Ray Test of Mini-drift Thick Gas Electron Multiplier Chamber for Transition Radiation Detector

    E-Print Network [OSTI]

    S. Yang; S. Das; B. Buck; C. Li; T. Ljubicic; R. Majka; M. Shao; N. Smirnov; G. Visser; Z. Xu; Y. Zhou

    2015-02-17T23:59:59.000Z

    A thick gas electron multiplier (THGEM) chamber with an effective readout area of 10$\\times$10 cm$^{2}$ and a 11.3 mm ionization gap has been tested along with two regular gas electron multiplier (GEM) chambers in a cosmic ray test system. The thick ionization gap makes the THGEM chamber a mini-drift chamber. This kind mini-drift THGEM chamber is proposed as part of a transition radiation detector (TRD) for identifying electrons at an Electron Ion Collider (EIC) experiment. Through this cosmic ray test, an efficiency larger than 94$\\%$ and a spatial resolution $\\sim$220 $\\mu$m are achieved for the THGEM chamber at -3.65 kV. Thanks to its outstanding spatial resolution and thick ionization gap, the THGEM chamber shows excellent track reconstruction capability. The gain uniformity and stability of the THGEM chamber are also presented.

  9. Permeability-thickness determination from transient production response at the southeast geysers

    SciTech Connect (OSTI)

    Faulder, D.D.

    1996-08-01T23:59:59.000Z

    The Fetkovich production decline curve analysis method was extended for application to vapor-dominated geothermal reservoirs for the purpose of estimating the permeability-thickness product (kh) from the transient production response. The analytic dimensionless terms for pressure, production rate, decline rate, and decline time were derived for saturated steam using the real gas potential and customary geothermal production units of pounds-mass per hour. The derived terms were numerically validating using ``Geysers-line`` reservoir properties at initial water saturation of 0 and at permeabilities of 1, 10, and 100 mD. The production data for 48 wells in the Southeast Geysers were analyzed and the permeability-thickness products determined from the transient production response using the Fetkovich production decline type curve. The kh results were in very good agreement with the published range at the Southeast Geysers and show regions of high permeability-thickness.

  10. 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

    2015-01-07T23:59:59.000Z

    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

  11. The Asymmetric Thick Disk: A Star Count and Kinematic Analysis. II The Kinematics

    E-Print Network [OSTI]

    Jeniffer E. Parker; Roberta M. Humphreys; Timothy C. Beers

    2003-11-30T23:59:59.000Z

    We report a kinematic signature associated with the observed asymmetry in the distribution of thick disk/inner halo stars interior to the Solar circle described in Paper I. In that paper we found a statistically significant excess (20% to 25 %) of stars in quadrant I (l ~ 20 deg to 55 deg) both above and below the plane (b ~ +/- 25 deg to +/- 45 deg) compared to the complementary region in quadrant IV. We have measured Doppler velocities for 741 stars, selected according to the same magnitude and color criteria, in the direction of the asymmetry and in the corresponding fields in quadrant IV. We have also determined spectral types and metallicities measured from the same spectra. We not only find an asymmetric distribution in the V_LSR velocities for the stars in the two regions, but the angular rate of rotation, w, for the stars in quadrant I reveals a slower effective rotation rate compared to the corresponding quadrant IV stars. We use our [Fe/H] measurements to separate the stars into the three primary population groups, halo, thick disk, and disk, and conclude that it is primarily the thick disk stars that show the slower rotation in quadrant I. A solution for the radial, tangential and vertical components of the V_LSR velocities, reveals a significant lag of ~ 80 to 90 km/s in the direction of Galactic rotation for the thick disk stars in quadrant I, while in quadrant IV, the same population has only a ~ 20 km/s lag. The results reported here support a rotational lag among the thick disk stars due to a gravitational interaction with the bar as the most likely explanation for the asymmetry in both the star counts and the kinematics. The affected thick disk stars, however, may be associated with the recently discovered Canis Major debris stream or a similar merger event (abridged).

  12. Thickness dependent exchange bias in martensitic epitaxial Ni-Mn-Sn thin films

    SciTech Connect (OSTI)

    Behler, Anna [IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, 01171 Dresden (Germany) [IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, 01171 Dresden (Germany); Department of Physics, Institute for Solid State Physics, Dresden University of Technology, 01062 Dresden (Germany); Teichert, Niclas; Auge, Alexander; Hütten, Andreas [Department of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, 33501 Bielefeld (Germany)] [Department of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, 33501 Bielefeld (Germany); Dutta, Biswanath; Hickel, Tilmann [Max-Planck Institut für Eisenforschung, 40237 Düsseldorf (Germany)] [Max-Planck Institut für Eisenforschung, 40237 Düsseldorf (Germany); Waske, Anja [IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, 01171 Dresden (Germany)] [IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, 01171 Dresden (Germany); Eckert, Jürgen [IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, 01171 Dresden (Germany) [IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, 01171 Dresden (Germany); Institute of Materials Science, Dresden University of Technology, 01062 Dresden (Germany)

    2013-12-15T23:59:59.000Z

    A thickness dependent exchange bias in the low temperature martensitic state of epitaxial Ni-Mn-Sn thin films is found. The effect can be retained down to very small thicknesses. For a Ni{sub 50}Mn{sub 32}Sn{sub 18} thin film, which does not undergo a martensitic transformation, no exchange bias is observed. Our results suggest that a significant interplay between ferromagnetic and antiferromagnetic regions, which is the origin for exchange bias, is only present in the martensite. The finding is supported by ab initio calculations showing that the antiferromagnetic order is stabilized in the phase.

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

    DOE Patents [OSTI]

    Steinman, D.A.

    1980-05-30T23:59:59.000Z

    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. 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

    2012-08-08T23:59:59.000Z

    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.

  15. Engineering guides for estimating cover material thickness and volume for uranium mill tailings

    SciTech Connect (OSTI)

    Rogers, V.C.; Nielson, K.K.; Merrell, G.B.

    1982-09-01T23:59:59.000Z

    Five nomographs have been prepared that facilitate the estimation of cover thickness and cover material volume for the Uranium Mill Tailing Remedial Action Program. Key parameters determined include the cover thickness with either a surface radon flux or a boundary radon air concentration criterion and the total volume of cover material required for two different treatments of the edge slopes. Also included in the engineering guide are descriptions and representative values for the radon source term, the diffusion coefficients and the key meteorological parameters. 16 refs., 7 figs., 2 tabs.

  16. Association of coal metamorphism and hydrothermal mineralization in Rough Creek fault zone and Fluorspar District, Western Kentucky

    SciTech Connect (OSTI)

    Hower, J.C.; Fiene, F.L.; Trinkle, E.J.

    1983-09-01T23:59:59.000Z

    The ambient coal rank (metamorphism) of the Carboniferous coals in the Western Kentucky coalfield ranges from high volatile A bituminous (vitrinite maximum reflectance up to 0.75% R/sub max/) in the Webster syncline (Webster and southern Union Counties) to high volatile C bituminous (0.45 to 0.60% R/sub max/) over most of the remainder of the area. Anomalous patterns of metamorphism, however, have been noted in coals recovered from cores and mines in fault blocks of the Rough Creek fault zone and Fluorspar District. Coals in Gil-30 borehole (Rough Creek faults, Bordley Quadrangle, Union County) vary with no regard for vertical position, from high volatile C(0.55% R/sub max/) to high volatile A (0.89%R/sub max) bituminous. Examination of the upper Sturgis Formation (Missourian/Virgilian) coals revealed that the higher rank (generally above 0.75% R/sub max/) coals had vein mineral assemblages of sphalerite, twinned calcite, and ferroan dolomite. Lower rank coals had only untwinned calcite. Several sites in Webster County contain various coals (Well (No. 8) to Coiltwon (No. 14)) with vitrinite reflectances up to 0.83% R/sub max/ and associated sphalerite mineralization. Mississippian and Lower Pennsylvanian (Caseyville Formation Gentry coal) coals in the mineralized Fluorspar District have ranks to nearly medium volatile bituminous (1.03% R/sub max/). The regional rank trend exhibited by the fualt zones is generally higher rank than the surrounding areas. Sphalerite mineralization in itself is not unique within Illinois basin coals, but if it was partly responsible for the metamorphism of these coals, then the fluid temperature must have been higher within the above mentioned fault complexes.

  17. The determination of the Reynolds shear stress distribution in the transition region resulting from a sudden increase in wall roughness in a two-dimensional channel

    E-Print Network [OSTI]

    Heilhecker, Joe Keith

    1962-01-01T23:59:59.000Z

    THE DETERMINATION OF THE REYNOLDS SHEAR STRESS DISTRIBUTION IN THE TRANSITION REGION RESULTING FROM A SUDDEN INCREASE IN WALL ROUGHNESS IN A TWO-DIMENSIONAL CHANNEL A Thesis By JOE K. HEI LHE CKER Submitted to the Graduate School... REGION RESULTING FROM A SUDDEN INCREASE IN WALL ROUGHNESS IN A TWO-DIMEN4$ONAL CHANNEL A Thesis By JOE K. HEI LHE CKER Approved as to style and content by: (Chairm o C mittee) (Head of Department) May 1962 TAB LE OF CONTE NT S Page List...

  18. Advances in Surface Plasmon Resonance Imaging Enable Quantitative Tracking of Nanoscale Changes in Thickness and

    E-Print Network [OSTI]

    Dutcher, John

    Advances in Surface Plasmon Resonance Imaging Enable Quantitative Tracking of Nanoscale Changes: To date, detailed studies of the thickness of coatings using surface plasmon resonance have been limited a significant improvement to surface plasmon resonance imaging (SPRi) that allows this sensitive technique

  19. Topology of desiccation crack patterns in clay and invariance of crack interface area with thickness

    E-Print Network [OSTI]

    Tajkera Khatun; Tapati Dutta; Sujata Tarafdar

    2014-12-09T23:59:59.000Z

    We study the crack patterns developed on desiccating films of an aqueous colloidal suspension of bentonite on a glass substrate. Varying the thickness of the layer $h$ gives the following new and interesting results: (i)We identify a critical thickness $h_{c}$, above which isolated cracks join each other to form a fully connected network. A topological analysis of the crack network shows that the Euler number falls to a minimum at $h_{c}$. (ii) We find further, that the total vertical surface area of the clay $A_v$, which has opened up due to cracking, is a constant independent of the layer thickness for $h \\geq h_c$. (iii) The total area of the glass substrate $A_s$, exposed by the hierarchical sequence of cracks is also a constant for $h \\geq h_c$. These results are shown to be consistent with a simple energy conservation argument, neglecting dissipative losses. (iv) Finally we show that if the crack pattern is viewed at successively finer resolution, the total cumulative area of cracks visible at a certain resolution, scales with the layer thickness. A suspension of Laponite in methanol is found to exhibit similar salient features (i)-(iv), though in this case the crack initiation process for very thin layers is quite different.

  20. 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.

    2010-01-01T23:59:59.000Z

    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...

  1. INVESTIGATION OF SEASONAL SEA-ICE THICKNESS VARIABILITY IN THE ROSS SEA Beth A. Schellenberg

    E-Print Network [OSTI]

    Geiger, Cathleen

    archive consists of over 20,000 records over the Antarc- tic pack ice between 1980 and the presentINVESTIGATION OF SEASONAL SEA-ICE THICKNESS VARIABILITY IN THE ROSS SEA Beth A. Schellenberg P1.23 1. INTRODUCTION A number of studies suggest a connections between sea-ice variability

  2. Ion adsorption and equilibrium distribution of charges in a cell of finite thickness

    E-Print Network [OSTI]

    Boyer, Edmond

    281 Ion adsorption and equilibrium distribution of charges in a cell of finite thickness G. Barbero-consistente, on évalue la distribution d'équilibre de charges dans une cellule d'épaisseur finie, en présence d'adsorption surface est évaluée, en étendant le problème classique d'adsorption de Langmuir aux situations loin du

  3. Improvement of radar ice-thickness measurements of Greenland outlet glaciers using SAR processing

    E-Print Network [OSTI]

    Braaten, David A.; Gogineni, S. Prasad; Tammana, Dilip; Namburi, Saikiran; Paden, John; Gurumoorthy, Krishna K.

    2002-01-01T23:59:59.000Z

    Extensive aircraft-based radar ice-thickness measurements over the interior and outlet-glacier regions of the Greenland ice sheet have been obtained by the University of Kansas since 1993, with the latest airborne surveys conducted in May 2001...

  4. 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

    2012-08-30T23:59:59.000Z

    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.

  5. Commercialization of thick film solar cell. Final technical report, 9/15/79-9/14/80

    SciTech Connect (OSTI)

    None

    1980-01-01T23:59:59.000Z

    Films of cadmium sulfide and cadmium telluride have been produced by screen printing and sintering. Cadmium sulfide films ten microns thick had a resistivity in the 10 ohm-cm range. A technique was developed for forming a cadmium telluride layer on top of a cadmium sulfide layer. Process control and device preparation are areas requiring further study.

  6. 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

  7. Aluminum hydroxide coating thickness measurements and brushing tests on K West Basin fuel elements

    SciTech Connect (OSTI)

    Pitner, A.L.

    1998-09-11T23:59:59.000Z

    Aluminum hydroxide coating thicknesses were measured on fuel elements stored in aluminum canisters in K West Basin using specially developed eddy current probes . The results were used to estimate coating inventories for MCO fuel,loading. Brushing tests successfully demonstrated the ability to remove the coating if deemed necessary prior to MCO loading.

  8. Near-Field Scanning Optical Microscopy of Temperature-and Thickness-Dependent Morphology and

    E-Print Network [OSTI]

    Buratto, Steve

    Near-Field Scanning Optical Microscopy of Temperature- and Thickness-Dependent Morphology 21, 2000 We use near-field scanning optical microscopy (NSOM) to probe the local optical spectroscopy with bulk techniques such as differ- ential scanning calorimetry (DSC) and X-ray diffractom- etry

  9. Lanthanum silicate gate dielectric stacks with subnanometer equivalent oxide thickness utilizing an interfacial silica consumption reaction

    E-Print Network [OSTI]

    Garfunkel, Eric

    Lanthanum silicate gate dielectric stacks with subnanometer equivalent oxide thickness utilizing-8087 Received 13 April 2005; accepted 6 June 2005; published online 26 July 2005 A silicate reaction between process route to interface elimination, while producing a silicate dielectric with a higher temperature

  10. Effects of thickness on the piezoelectric and dielectric properties of lead zirconate titanate thin films

    E-Print Network [OSTI]

    Sottos, Nancy R.

    Lead zirconate titanate PZT thin films with a Zr/Ti ratio of 52/48 were deposited on platinized silicon. Both the piezoelectric properties and the dielectric constants of the PZT thin films were found thin films. The measured changes in properties with thickness were correlated with the residual stress

  11. Determination of refractive index, thickness, and the optical losses of thin films from

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Determination of refractive index, thickness, and the optical losses of thin films from prism­film.4760, 300.1030. 1. Introduction Transparent thin films find wide applications in optics: coating, sensors and optical losses. The optical losses of a thin film have three different origins: sur- face scattering due

  12. Radar Measurements of Ice Sheet Thickness of Outlet Glaciers in Greenland D. Braaten+

    E-Print Network [OSTI]

    Kansas, University of

    Radar Measurements of Ice Sheet Thickness of Outlet Glaciers in Greenland D. Braaten+ and S of Kansas Lawrence, KS 66045 U.S.A. Abstract ­ We have conducted airborne measurements over the Greenland the mass balance of the Greenland ice sheet, the University of Kansas has been operating an airborne radio

  13. Smooth thick braneworlds and the Gibbons-Kallosh-Linde no-go theorem

    E-Print Network [OSTI]

    Marco Dias; J. M. Hoff da Silva; Roldão da Rocha

    2015-04-17T23:59:59.000Z

    After working out the so called braneworld sum rules formalism in order to encompass Gauss-Bonnet terms, the generation of thick branes is proposed, even with a periodic extra dimension, what circumvents the Gibbons-Kallosh-Linde no-go theorem in this context.

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

    SciTech Connect (OSTI)

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

    1993-04-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    1993-01-01T23:59:59.000Z

    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.

  16. THE MOTION OF SUPERCONDUCTING VORTICES IN THIN FILMS OF VARYING THICKNESS

    E-Print Network [OSTI]

    Chapman, Jon

    with superconductor/vacuum interfaces is considered. A vortex is #12;rst shown to intersect such an interface normallyTHE MOTION OF SUPERCONDUCTING VORTICES IN THIN FILMS OF VARYING THICKNESS S.J. CHAPMAN #3; D.R. HERON y MATHEMATICAL INSTITUTE OXFORD OX1 3LB UK Abstract. The interaction of superconducting vortices

  17. Thickness limitations in carbon nanotube reinforced silicon nitride coatings synthesized by vapor infiltration

    SciTech Connect (OSTI)

    Eres, Gyula [ORNL

    2012-01-01T23:59:59.000Z

    Chemical vapor infiltration is a convenient method for synthesizing carbon nanotube (CNT)-reinforced ceramic coatings. The thickness over which infiltration is relatively uniform is limited by gas phase diffusion in the pore structure. These effects were investigated in two types of silicon nitride matrix composites. With CNTs that were distributed uniformly on the substrate surface dense coatings were limited to thicknesses of several microns. With dual structured CNT arrays produced by photolithography coatings up to 400 gm thick were obtained with minimal residual porosity. Gas transport into these dual structured materials was facilitated by creating micron sized channels between "CNT pillars" (i.e. each pillar consisted of a large number of individual CNTs). The experimental results are consistent with basic comparisons between the rates of gas diffusion and silicon nitride growth in porous structures. This analysis also provides a general insight into optimizing infiltration conditions during the fabrication of thick CNT-reinforced composite coatings. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  18. Evaluation of the Quality of Thick Fibre Composites Using Immersion and Air-

    E-Print Network [OSTI]

    Evaluation of the Quality of Thick Fibre Composites Using Immersion and Air- Coupled Ultrasonic. Two ultrasonic through-transmission techniques were evaluated: immersion and air-coupled technique. The immersion system was used for frequencies from 1 MHz to 10 MHz. The frequency range for the air

  19. 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

  20. 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

  1. 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

  2. An ordinary differential equation model for full thickness wounds and the effects of diabetes

    E-Print Network [OSTI]

    Maini, Philip K.

    An ordinary differential equation model for full thickness wounds and the effects of diabetes L and diabetic healing. The model can be used to estimate the contributions of growth and contraction to dermal healing. Increasing dermal growth is suggested as a treatment for enhancing healing of diabetic wounds

  3. 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 ...

  4. Vertical strain and doping gradients in thick GaN layers H. Siegle,a)

    E-Print Network [OSTI]

    Nabben, Reinhard

    between layer and common substrates, e.g., sapphire or GaAs.1 Consequently, most GaN layers and also from the surface of the GaN layer nearer to the substrate interface, as can be seen from the CLVertical strain and doping gradients in thick GaN layers H. Siegle,a) A. Hoffmann, L. Eckey, and C

  5. Factors affecting the availability of thick epiphyte mats and other potential nest platforms for

    E-Print Network [OSTI]

    Factors affecting the availability of thick epiphyte mats and other potential nest platforms, Catherine Conroy, Volker Bahn, Irene A. Manley, Alvin Cober, and David B. Lank Abstract: Nest platforms about factors that affect the availability of platforms or the growth of canopy epiphytes that provide

  6. FLOW CONDITIONING DESIGN IN THICK LIQUID PROTECTION S.G. Durbin

    E-Print Network [OSTI]

    California at San Diego, University of

    issuing downwards from nozzles of thickness (small dimension) = 1 cm into ambient air for Reynolds conditioner was studied. As the flow conditioning element immediately upstream of the nozzle inlet, fine, and that free-surface fluctuations are strongly affected by changes in flow conditioner design, even in the near

  7. Terahertz Sensor for Non-Contact Thickness and Quality Measurement of Automobile Paints of Varying Complexity

    E-Print Network [OSTI]

    Su, Ke; Shen, Yao-Chun; Zeitler, J. Axel

    2014-06-06T23:59:59.000Z

    to resolve coating layers down to a thickness of 18 $mu{hbox{m}}$ and was validated for both single- and multi-layer automobile paint samples. Results of the terahertz measurements were benchmarked against other techniques that are currently used for non...

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

    SciTech Connect (OSTI)

    Sharath, S. U., E-mail: sharath@oxide.tu-darmstadt.de; Kurian, J.; Komissinskiy, P.; Hildebrandt, E.; Alff, L. [Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt (Germany); Bertaud, T.; Walczyk, C.; Calka, P. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Brandenburgische Technische Universität, Konrad-Zuse-Strasse 1, 03046 Cottbus (Germany)

    2014-08-18T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Lehmann, Jarvis Craig

    1992-01-01T23:59:59.000Z

    of different thickness 1T compact tension specimens with the same initial crack length were tested using ASTM E 813-87 multiple specimen methodology as a guide. Six J-R curves were produced corresponding to the mean thickness of each specimen set; mean...'s decreasing toughness behavior with increasing thickness. UHMW-PE was found to have a tearing resistance, J-R curve, which increases with specimen thickness and crack growth and comparable to tough, high tearing resistant steels. This high tearing...

  10. Effect of discharge current and deposition temperature on roughness and density of NbC films fabricated by ion beam sputtering technique

    SciTech Connect (OSTI)

    Dhawan, Rajnish, E-mail: rajnish@rrcat.gov.in; Rai, Sanjay, E-mail: rajnish@rrcat.gov.in; Lodha, G. S., E-mail: rajnish@rrcat.gov.in [X-ray optics Section, Indus Synchrotron Utilization Division, Raja Ramanna Center for Advanced Technology, Indore-452013 (India)

    2014-04-24T23:59:59.000Z

    NbC films were prepared using Ion beam sputtering system at various discharges current from 0.4 amps to 1.2 amps at room temperature. Effect of temperature on NbC films were also studied by depositing NbC films at various temperatures from room temperature to 200,300,400 and 600°C. X-ray reflectivity (XRR) study shows that surface roughness of the film decreases with decrease in discharge current. The optimum lowest roughness 3.2Å having density 92% of bulk was achieved at discharge current 0.6 amps at 3.0 cm{sup 3}/min Ar gas flow. X-ray study also shows that film roughness decreases with increase in temperature of the film and after a certain temperature it increases with increase in temperature. The lowest surface roughness 2.1Å was achieved at 300°C with density 83% of bulk NbC at constant discharge current 0.6 amps.

  11. 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

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

  12. D etailed m odeling ofreactive flow s th rough geologicm edia is necessary to understand a num ber of environm entalproblem s of national

    E-Print Network [OSTI]

    Mills, Richard

    fluids and geologic seq uestration of CO2 in deep reservoirs. Such problem s generally req uire sim s to th e surface , for e xam ple , th rough abandone d w e lls and fracture s in cap rock s. Accurate

  13. MAPPING THE STELLAR STRUCTURE OF THE MILKY WAY THICK DISK AND HALO USING SEGUE PHOTOMETRY

    SciTech Connect (OSTI)

    De Jong, Jelte T. A.; Rix, Hans-Walter; Martin, Nicolas F. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Yanny, Brian [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Beers, Timothy C., E-mail: dejong@mpia.d [Department of Physics and Astronomy and JINA: Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 48824 (United States)

    2010-05-01T23:59:59.000Z

    We map the stellar structure of the Galactic thick disk and halo by applying color-magnitude diagram (CMD) fitting to photometric data from the Sloan Extension for Galactic Understanding and Exploration (SEGUE) survey. The SEGUE imaging scans allow, for the first time, a comprehensive analysis of Milky Way structure at both high and low latitudes using uniform Sloan Digital Sky Survey photometry. Incorporating photometry of all relevant stars simultaneously, CMD fitting bypasses the need to choose single tracer populations. Using old stellar populations of differing metallicities as templates, we obtain a sparse three-dimensional map of the stellar mass distribution at |Z|>1 kpc. Fitting a smooth Milky Way model comprising exponential thin and thick disks and an axisymmetric power-law halo allows us to constrain the structural parameters of the thick disk and halo. The thick-disk scale height and length are well constrained at 0.75 {+-} 0.07 kpc and 4.1 {+-} 0.4 kpc, respectively. We find a stellar halo flattening within {approx}25 kpc of c/a = 0.88 {+-} 0.03 and a power-law index of 2.75 {+-} 0.07 (for 7 kpc {approx_lt}R{sub GC} {approx_lt} 30 kpc). The model fits yield thick-disk and stellar halo densities at the solar location of {rho}{sub thick,sun} = 10{sup -2.3{+-}0.1} M{sub sun} pc{sup -3} and {rho}{sub halo,sun} = 10{sup -4.20{+-}0.05} M{sub sun} pc{sup -3}, averaging over any substructures. Our analysis provides the first clear in situ evidence for a radial metallicity gradient in the Milky Way's stellar halo: within R {approx_lt} 15 kpc the stellar halo has a mean metallicity of [Fe/H] {approx_equal} -1.6, which shifts to [Fe/H] {approx_equal} -2.2 at larger radii, in line with the two-component halo deduced by Carollo et al. from a local kinematic analysis. Subtraction of the best-fit smooth and symmetric model from the overall density maps reveals a wealth of substructures at all latitudes, some attributable to known streams and overdensities, and some new. A simple warp cannot account for the low latitude substructure, as overdensities occur simultaneously above and below the Galactic plane.

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

    SciTech Connect (OSTI)

    Djurabekova, Flyura, E-mail: flyura.djurabekova@helsinki.fi; Ruzibaev, Avaz; Parviainen, Stefan [Helsinki Institute of Physics and Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 Helsinki (Finland); Holmström, Eero [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland); Department of Earth Sciences, Faculty of Maths and Physical Sciences, UCL Earth Sciences, Gower Street, London WC1E 6BT (United Kingdom); Hakala, Mikko [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland)

    2013-12-28T23:59:59.000Z

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

  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. [Inst. of Nucl. Res. of the Hungarian Acad. of Sci. (ATOMKI), H-4001 Debrecen, P.O. Box 51 (Hungary); Physics Department, Faculty of Science, University of Zagreb (Croatia); Kernfysisch Versneller Instituut, University of Groningen, Groningen (Netherlands); and others

    2012-10-20T23:59:59.000Z

    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. 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)

    2002-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Li Haitao; Liu Yuxiao; Zhao Zhenhua; Guo Heng [Institute of Theoretical Physics, Lanzhou University, Lanzhou 730000 (China)

    2011-02-15T23:59:59.000Z

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

  18. 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

    2002-12-13T23:59:59.000Z

    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 $R_{cut}$.

  19. 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)

    2009-10-13T23:59:59.000Z

    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.

  20. High efficiency proton beam generation through target thickness control in femtosecond laser-plasma interactions

    SciTech Connect (OSTI)

    Green, J. S., E-mail: james.green@stfc.ac.uk; Robinson, A. P. L.; Booth, N.; Carroll, D. C.; Rusby, D.; Wilson, L. [Central Laser Facility, STFC Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom); Dance, R. J. [York Plasma Institute, Department of Physics, University of York, York YO10 5DD (United Kingdom); Gray, R. J.; MacLellan, D. A.; McKenna, P. [SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Murphy, C. D. [SUPA, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ (United Kingdom)

    2014-05-26T23:59:59.000Z

    Bright proton beams with maximum energies of up to 30?MeV have been observed in an experiment investigating ion sheath acceleration driven by a short pulse (<50 fs) laser. The scaling of maximum proton energy and total beam energy content at ultra-high intensities of ?10{sup 21} W cm{sup ?2} was investigated, with the interplay between target thickness and laser pre-pulse found to be a key factor. While the maximum proton energies observed were maximised for ?m-thick targets, the total proton energy content was seen to peak for thinner, 500?nm, foils. The total proton beam energy reached up to 440 mJ (a conversion efficiency of 4%), marking a significant step forward for many laser-driven ion applications. The experimental results are supported by hydrodynamic and particle-in-cell simulations.

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

    E-Print Network [OSTI]

    Fattoyev, F J

    2013-01-01T23:59:59.000Z

    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.

  2. Atmospheric pressure spatial atomic layer deposition web coating with in situ monitoring of film thickness

    SciTech Connect (OSTI)

    Yersak, Alexander S.; Lee, Yung C. [Department of Mechanical Engineering, University of Colorado at Boulder, 1045 Regent Drive, 422 UCB, Boulder, Colorado 80309-0422 (United States); Spencer, Joseph A.; Groner, Markus D., E-mail: mgroner@aldnanosolutions.com [ALD NanoSolutions, Inc., 580 Burbank Street, Unit 100, Broomfield, Colorado 80020 (United States)

    2014-01-15T23:59:59.000Z

    Spectral reflectometry was implemented as a method for in situ thickness monitoring in a spatial atomic layer deposition (ALD) system. Al{sub 2}O{sub 3} films were grown on a moving polymer web substrate at 100?°C using an atmospheric pressure ALD web coating system, with film growth of 0.11–0.13?nm/cycle. The modular coating head design and the in situ monitoring allowed for the characterization and optimization of the trimethylaluminum and water precursor exposures, purge flows, and web speed. A thickness uniformity of ±2% was achieved across the web. ALD cycle times as low as 76?ms were demonstrated with a web speed of 1?m/s and a vertical gap height of 0.5?mm. This atmospheric pressure ALD system with in situ process control demonstrates the feasibility of low-cost, high throughput roll-to-roll ALD.

  3. 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, E-mail: ashok553@nplindia.org [CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012 (India)

    2014-08-15T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    L. H. Perdieu

    2009-09-01T23:59:59.000Z

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

  5. Infrared Imaging of the Nanometer-Thick Accumulation Layer in Organic Field-Effect Transistors

    E-Print Network [OSTI]

    Z. Q. Li; G. M. Wang; N. Sai; D. Moses; M. C. Martin; M. Di Ventra; A. J. Heeger; D. N. Basov

    2006-02-09T23:59:59.000Z

    We report on infrared (IR) spectro-microscopy of the electronic excitations in nanometer-thick accumulation layers in FET devices based on poly(3-hexylthiophene). IR data allows us to explore the charge injection landscape and uncovers the critical role of the gate insulator in defining relevant length scales. This work demonstrates the unique potential of IR spectroscopy for the investigation of physical phenomena at the nanoscale occurring at the semiconductor-insulator interface in FET devices.

  6. 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

    2011-12-23T23:59:59.000Z

    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.

  7. Extension of the Si:C Stressor Thickness by Using Multiple ClusterCarbon Species

    SciTech Connect (OSTI)

    Sekar, Karuppanan; Krull, Wade [SemEquip, Inc. N. Billerica, MA, 01862 (United States)

    2011-01-07T23:59:59.000Z

    ClusterCarbon implantation is now well established as an attractive alternative for producing stress in advanced NMOS devices. ClusterCarbon has the advantage over monomer carbon implant in it's self-amorphization feature, eliminating the need for PAI implantation while producing highly substitutional carbon incorporation. To date, the limitation of this approach has been the high energy limit, due to the extraction limit of the available production tools for the preferred carbon species, which has been the C7Hx molecule. It is noted that the C7 species is produced by the breakup of the parent C14H14 molecule in the ion source. It is further noted that the preferred method of producing the Si:C stress layer is a multiple implant sequence with ClusterCarbon implants at various energies and doses designed to produce a carbon profile which is constant in-depth. The stressor thickness limit using C7 is known to be about 40 nm, which is less than the stressor thickness used in the conventional SiGe process for PMOS. In this work, it is shown that utilizing the C5 molecule which is also available from the breakup of C14H14 enables the stressor layer thickness to be extended to at least 60 nm, which is consistent with the conventional SiGe process. It will be shown that one additional C5 implant, performed after a standard C7 multiple implant sequence, can produce the extension of the stressor thickness while maintaining the flat depth profile. A detailed process characterization will be shown for this new process sequence.

  8. Investigation of arc length versus flange thickness while using an arc voltage controller

    SciTech Connect (OSTI)

    Daumeyer, G.J.

    1994-11-01T23:59:59.000Z

    An arc voltage controller (AVC) for gas tungsten arc welding will change arc length when flange thickness changes while all other variables, including AVC setting, are held constant. A procedure for calibrating an LVDT (linear variable displacement transducer) used for electrode assembly motion monitoring was proven for laboratory setups and special investigations. A partial characterization on the deadband and sensitivity control settings of the Cyclomatic AVC was completed.

  9. Correlation between AlPO4 nanoparticle coating thickness on LiCoO2 cathode and thermal stability

    E-Print Network [OSTI]

    Cho, Jaephil

    Correlation between AlPO4 nanoparticle coating thickness on LiCoO2 cathode and thermal stability cathode. They coated the cathode with AlPO4 nanoparticles prepared from water [13]. The AlPO4 coating solÁ/gel coating method, this nanoparticle coating led to the easy control of the coating thickness

  10. 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

  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

    . The combination of the SAR imagery and ULS observations also allow measurement of the pack ice advection velocityObservations of ice thickness and frazil ice in the St. Lawrence Island polynya from satellite define a thermal ice thickness from the AVHRR retrieval of ice surface temperature combined

  12. Thick Braneworlds and the Gibbons-Kallosh-Linde No-go Theorem in the Gauss-Bonnet Framework

    E-Print Network [OSTI]

    M. Dias; J. M. Hoff da Silva; Roldao da Rocha

    2015-04-16T23:59:59.000Z

    The sum rules related to thick braneworlds are constructed, in order to encompass Gauss-Bonnet terms. The generation of thick branes is hence proposed in a periodic extra dimension scenario, what circumvents the Gibbons-Kallosh-Linde no-go theorem in this context.

  13. 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.

    2011-07-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Bradley, P. A., E-mail: pbradley@lanl.gov [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-06-15T23:59:59.000Z

    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.

  15. Thickness-based adaptive mesh refinement methods for multi-phase flow simulations with thin regions

    SciTech Connect (OSTI)

    Chen, Xiaodong [The State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Yang, Vigor, E-mail: vigor.yang@aerospace.gatech.edu [School of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0150 (United States)

    2014-07-15T23:59:59.000Z

    In numerical simulations of multi-scale, multi-phase flows, grid refinement is required to resolve regions with small scales. A notable example is liquid-jet atomization and subsequent droplet dynamics. It is essential to characterize the detailed flow physics with variable length scales with high fidelity, in order to elucidate the underlying mechanisms. In this paper, two thickness-based mesh refinement schemes are developed based on distance- and topology-oriented criteria for thin regions with confining wall/plane of symmetry and in any situation, respectively. Both techniques are implemented in a general framework with a volume-of-fluid formulation and an adaptive-mesh-refinement capability. The distance-oriented technique compares against a critical value, the ratio of an interfacial cell size to the distance between the mass center of the cell and a reference plane. The topology-oriented technique is developed from digital topology theories to handle more general conditions. The requirement for interfacial mesh refinement can be detected swiftly, without the need of thickness information, equation solving, variable averaging or mesh repairing. The mesh refinement level increases smoothly on demand in thin regions. The schemes have been verified and validated against several benchmark cases to demonstrate their effectiveness and robustness. These include the dynamics of colliding droplets, droplet motions in a microchannel, and atomization of liquid impinging jets. Overall, the thickness-based refinement technique provides highly adaptive meshes for problems with thin regions in an efficient and fully automatic manner.

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

    SciTech Connect (OSTI)

    Figus, Cristiana, E-mail: cristiana.figus@dsf.unica.it; Quochi, Francesco, E-mail: cristiana.figus@dsf.unica.it; Artizzu, Flavia, E-mail: cristiana.figus@dsf.unica.it; Saba, Michele, E-mail: cristiana.figus@dsf.unica.it; Marongiu, Daniela, E-mail: cristiana.figus@dsf.unica.it; Mura, Andrea; Bongiovanni, Giovanni [Dipartimento di Fisica - University of Cagliari, S.P. Km 0.7, I-09042 Monserrato (Canada) (Italy); Floris, Francesco; Marabelli, Franco; Patrini, Maddalena; Fornasari, Lucia [Dipartimento di Fisica - University of Pavia, Via Agostino Bassi 6, I-27100 Pavia (PV) (Italy); Pellacani, Paola; Valsesia, Andrea [Plasmore S.r.l. -Via Grazia Deledda 4, I-21020 Ranco (Vatican City State, Holy See) (Italy)

    2014-10-21T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Li, Hongkai; Qu, Zilian; Zhao, Qian; Tian, Fangxin; Zhao, Dewen; Meng, Yonggang; Lu, Xinchun [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)] [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

    2013-12-15T23:59:59.000Z

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

  18. Localization and mass spectra of fermions on symmetric and asymmetric thick branes

    SciTech Connect (OSTI)

    Liu Yuxiao; Fu, C.-E; Zhao Li; Duan Yishi [Institute of Theoretical Physics, Lanzhou University, Lanzhou 730000 (China)

    2009-09-15T23:59:59.000Z

    A three-parameter (positive odd integer s, thickness factor {lambda}, and asymmetry factor a) family of asymmetric thick brane solutions in five dimensions were constructed from a two-parameter (s and {lambda}) family of symmetric ones in by R. Guerrero, R. O. Rodriguez, and R. Torrealba in [Phys. Rev. D 72, 124012 (2005).]. The values s=1 and s{>=}3 correspond to single branes and double branes, respectively. These branes have very rich inner structure. In this paper, by presenting the mass-independent potentials of Kaluza-Klein (KK) modes in the corresponding Schroedinger equations, we investigate the localization and mass spectra of fermions on the symmetric and asymmetric thick branes in an anti-de Sitter background. In order to analyze the effect of gravity-fermion interaction (i.e., the effect of the inner structure of the branes) and scalar-fermion interaction to the spectrum of fermion KK modes, we consider three kinds of typical kink-fermion couplings. The spectra of left chiral fermions for these couplings consist of a bound zero mode and a series of gapless continuous massive KK modes, some discrete bound KK modes including zero mode (exist mass gaps), and a series of continuous massive KK modes, infinite discrete bound KK modes, respectively. The structures of the spectra are investigated in detail.

  19. 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)

    2014-02-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    A. Krasznahorkay; L. Stuhl; M. Csatlós; A. Algora; J. Gulyás; J. Timár; N. Paar; D. Vretenar; K. Boretzky; M. Heil; Yu. A. Litvinov; D. Rossi; C. Scheidenberger; H. Simon; H. Weick; A. Bracco; S. Brambilla; N. Blasi; F. Camera; A. Giaz; B. Million; L. Pellegri; S. Riboldi; O. Wieland; S. Altstadt; M. Fonseca; J. Glorius; K. Göbel; T. Heftrich; A. Koloczek; S. Kräckmann; C. Langer; R. Plag; M. Pohl; G. Rastrepina; R. Reifarth; S. Schmidt; K. Sonnabend; M. Weigand; M. N. Harakeh; N. Kalantar-Nayestanaki; C. Rigollet; S. Bagchi; M. A. Najafi; T. Aumann; L. Atar; M. Heine; M. Holl; A. Movsesyan; P. Schrock; V. Volkov; F. Wamers; E. Fiori; B. Löher; J. Marganiec; D. Savran; H. T. Johansson; P. Diaz Fernández; U. Garg; D. L. Balabanski

    2012-06-20T23:59:59.000Z

    The gamma-decay of the anti-analog of the giant dipole resonance (AGDR) has been measured to the isobaric analog state excited in the p(124Sn,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 random-phase approximation (RPA) and turned out to be very sensitive to the neutron-skin thickness (\\DeltaR_(pn)). By comparing the theoretical results with the measured one, the \\DeltaR_(pn) value for 124Sn was deduced to be 0.175 \\pm 0.048 fm, which agrees well with the previous results. The energy of the AGDR measured previously for ^(208)Pb was also used to determine the \\DeltaR_(pn) for ^(208)Pb. In this way a very precise \\DeltaR_(pn) = 0.181 \\pm 0.031 neutron-skin thickness has been obtained for 208Pb. The present method offers new possibilities for measuring the neutron-skin thicknesses of very exotic isotopes.

  1. Electrocaloric properties of ferroelectric-paraelectric superlattices controlled by the thickness of paraelectric layer in a wide temperature range

    SciTech Connect (OSTI)

    Ma, D. C.; Lin, S. P. [Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, Guangzhou 510275 (China); Micro and Nano Physics and Mechanics Research Laboratory, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Chen, W. J.; Zheng, Yue, E-mail: zhengy35@mail.sysu.edu.cn; Xiong, W. M. [State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275 (China); Micro and Nano Physics and Mechanics Research Laboratory, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Wang, Biao, E-mail: wangbiao@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275 (China)

    2014-10-15T23:59:59.000Z

    As functions of the paraelectric layer thickness, misfit strain and temperature, the electrocaloric properties of ferroelectric-paraelectric superlattices are investigated using a time-dependent Ginzburg-Landau thermodynamic model. Ferroelectric phase transition driven by the relative thickness of the superlattice is found to dramatically impact the electrocaloric response. Near the phase transition temperature, the magnitude of the electrocaloric effect is maximized and shifted to lower temperatures by increasing the relative thickness of paraelectric layer. Theoretical calculations also imply that the electrocaloric effect of the superlattices depends not only on the relative thickness of paraelectric layer but also on misfit strain. Furthermore, control of the relative thickness of paraelectric layer and the misfit strain can change availably both the magnitude and the temperature sensitivity of the electrocaloric effect, which suggests that ferroelectric-paraelectric superlattices may be promising candidates for use in cooling devices in a wide temperature range.

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

    SciTech Connect (OSTI)

    Not Available

    2013-11-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Kwong, Edmund Ming Yip

    2009-01-01T23:59:59.000Z

    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 ...

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

    SciTech Connect (OSTI)

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

    2013-10-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Mueller, D [PPPL; Roquemore, A L [PPPL; Jaworski, M [PPPL; Skinner, C H [PPPL; Miller, J [PPPL; Creely, A [PPPL; Raman, P [2University of Illinois, Champaign, IL, USA; Ruzic, D [2University of Illinois, Champaign, IL, USA

    2014-07-01T23:59:59.000Z

    Rutherford backscattering (RBS) of energetic particles can be used to determine the thickness of a coating of a low-Z material over a heavier substrate. Simulations indicate that 5 MeV alpha particles from an Am source 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 hours of counting. This technique could be used to measure any thin, low-Z material coating (up to 1 mg/cm^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.

  6. Carbon, nitrogen and $\\alpha$-element abundances determine the formation sequence of the Galactic thick and thin disks

    E-Print Network [OSTI]

    Masseron, T

    2015-01-01T23:59:59.000Z

    Using the DR12 public release of APOGEE data, we show that thin and thick disk separate very well in the space defined by [$\\alpha$/Fe], [Fe/H] and [C/N]. Thick disk giants have both higher [C/N] and higher [$\\alpha$/Fe] than do thin disk stars with similar [Fe/H]. We deduce that the thick disk is composed of lower mass stars than the thin disk. Considering the fact that at a given metallicity there is a one-to-one relation between stellar mass and age, we are then able to infer the chronology of disk formation. Both the thick and the thin disks - defined by [$\\alpha$/Fe] -- converge in their dependance on [C/N] and [C+N/Fe] at [Fe/H]$\\approx$-0.7. We conclude that 1) the majority of thick disk stars formed earlier than did the thin disk stars 2) the formation histories of the thin and thick disks diverged early on, even when the [Fe/H] abundances are similar 3) that the star formation rate in the thin disk has been lower than in the thick disk, at all metallicities. Although these general conclusions remain ...

  7. 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,

    2001-01-01T23:59:59.000Z

    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.

  8. A study on the evolution of dielectric function of ZnO thin films with decreasing film thickness

    SciTech Connect (OSTI)

    Li, X. D.; Chen, T. P., E-mail: echentp@ntu.edu.sg; Liu, P. [School of Electrical and Electronic Engineering, Nanyang Technological University, 639798 Singapore (Singapore); Liu, Y. [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology, Chengdu 610054 (China); Liu, Z. [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Leong, K. C. [GLOBALFOUNDRIES Singapore Pte Ltd, 738406 Singapore (Singapore)

    2014-03-14T23:59:59.000Z

    Dielectric function, band gap, and exciton binding energies of ultrathin ZnO films as a function of film thickness have been obtained with spectroscopic ellipsometry. As the film thickness decreases, both real (?{sub 1}) and imaginary (?{sub 2}) parts of the dielectric function decrease significantly, and ?{sub 2} shows a blue shift. The film thickness dependence of the dielectric function is shown related to the changes in the interband absorption, discrete-exciton absorption, and continuum-exciton absorption, which can be attributed to the quantum confinement effect on both the band gap and exciton binding energies.

  9. Coal-bench architecture as a means of understanding regional changes in coal thickness and quality

    SciTech Connect (OSTI)

    Greb, S.F.; Eble, C.F. [Kentucy Geological Survey, Lexington, KY (United States); Hower, J.C. [Center for Applied Research, Lexington, KY (United States)

    1996-09-01T23:59:59.000Z

    Analysis of the Fire Creek (Westphalian B), Pond Creek (lower Westphalian B), and Stockton (Westphalian B) coals, three of the most heavily mined coals in the Central Appalachian Basin, shows that all have a similar multiple-bench architecture of at least two benches split by a regional clastic parting or durain. Coal benches beneath regionally extensive partings are generally less continuous, thinner, more palynologically variable, higher in ash yield, and higher in sulfur content than coal benches above regional partings in all three coals. Where thick, benches above regional partings tend to exhibit temporal palynological changes from lycopod- to fern-dominant. Where inertinite-rich/fern-dominant benches are overlain by additional benches, the upper benches are limited in extent, variable in thickness, high in sulfur content and ash yield, and split away from the coal. The multiple-bench architecture exhibited by these coals is interpreted to represent a cyclic mire succession that was common in the Middle Pennsylvanian. Peats began as planar mires infilling an irregular topography during rising base level. When the topography was infilled, unconfined flooding was possible and resulted in widespread partings. Ponding above these clay-rich flood deposits led to re-establishment of new planar mires with greater continuity than the underlying mires. The extent of these mires provided buffers to clastic influx and, in many cases, allowed domed conditions to develop. Doming resulted in thick, high-quality coal benches. In some cases, a third stage of planar peats, with similar characteristics to the planar peats at the base of the beds, developed on the unevenly distributed clastics that buried underlying mires during continued base-level rise.

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

    SciTech Connect (OSTI)

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

    1998-05-01T23:59:59.000Z

    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.

  11. Optical instrument for measurement of vaginal coating thickness by drug delivery formulations

    SciTech Connect (OSTI)

    Henderson, Marcus H.; Peters, Jennifer J.; Walmer, David K.; Couchman, Grace M.; Katz, David F. [Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States); Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina 27710 (United States); Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 and Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina 27710 (United States)

    2005-03-01T23:59:59.000Z

    An optical device has been developed for imaging the human vaginal epithelial surfaces, and quantitatively measuring distributions of coating thickness of drug delivery formulations - such as gels - applied for prophylaxis, contraception or therapy. The device consists of a rigid endoscope contained within a 27-mm-diam hollow, polished-transparent polycarbonate tube (150 mm long) with a hemispherical cap. Illumination is from a xenon arc. The device is inserted into, and remains stationary within the vagina. A custom gearing mechanism moves the endoscope relative to the tube, so that it views epithelial surfaces immediately apposing its outer surface (i.e., 150 mm long by 360 deg. azimuthal angle). Thus, with the tube fixed relative to the vagina, the endoscope sites local regions at distinct and measurable locations that span the vaginal epithelium. The returning light path is split between a video camera and photomultiplier. Excitation and emission filters in the light path enable measurement of fluorescence of the sited region. Thus, the instrument captures video images simultaneously with photometric measurement of fluorescence of each video field [{approx}10 mm diameter; formulations are labeled with 0.1% w/w United States Pharmacoepia (USP) injectable sodium fluorescein]. Position, time and fluorescence measurements are continuously displayed (on video) and recorded (to a computer database). The photomultiplier output is digitized to quantify fluorescence of the endoscope field of view. Quantification of the thickness of formulation coating of a surface sited by the device is achieved due to the linear relationship between thickness and fluorescence intensity for biologically relevant thin layers (of the order of 0.5 mm). Summary measures of coating have been developed, focusing upon extent, location and uniformity. The device has begun to be applied in human studies of model formulations for prophylaxis against infection with HIV and other sexually transmitted pathogens.

  12. Iron line profiles and self-shadowing from relativistic thick accretion discs

    E-Print Network [OSTI]

    Sheng-Miao Wu; Ting-Gui Wang

    2008-07-11T23:59:59.000Z

    We present Fe Kalpha line profiles from and images of relativistic discs with finite thickness around a rotating black hole using a novel code. The line is thought to be produced by iron fluorescence of a relatively cold X-ray illuminated material in the innermost parts of the accretion disc and provides an excellent diagnostic of accretion flows in the vicinity of black holes. Previous studies have concentrated on the case of a thin, Keplerian accretion disc. This disc must become thicker and sub-Keplerian with increasing accretion rates. These can affect the line profiles and in turn can influence the estimation of the accretion disc and black hole parameters from the observed line profiles. We here embark on, for the first time, a fully relativistic computation which offers key insights into the effects of geometrical thickness and the sub-Keplerian orbital velocity on the line profiles. We include all relativistic effects such as frame-dragging, Doppler boost, time dilation, gravitational redshift and light bending. We find that the separation and the relative height between the blue and red peaks of the line profile diminish as the thickness of the disc increases. This code is also well-suited to produce accretion disc images. We calculate the redshift and flux images of the accretion disc and find that the observed image of the disc strongly depends on the inclination angle. The self-shadowing effect appears remarkable for a high inclination angle, and leads to the black hole shadow being completely hidden by the disc itself.

  13. 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

    2006-06-27T23:59:59.000Z

    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.

  14. 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. [INFN, sezione di Milano, via Celoria 16, I-20133 Milano (Italy); Saha Institute of Nuclear Physics, Kolkata 700064 (India); Dipartimento di Fisica, Universita degli Studi di Milano and INFN, Sezione di Milano, 20133 Milano (Italy); Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States) and Institute of Theoretical Physics, University of Warsaw, Hoza 69, PL-00-681 Warsaw (Poland); Physics Department, Faculty of Science, University of Zagreb, Zagreb (Croatia); Department of Physics, Florida State University, Tallahassee, FL 32306 (United States); Institut fuer Theoretische Physik II, Universitaet Erlangen-Nuernberg, Staudtstrasse 7, D-91058 Erlangen (Germany); Physics Department, Faculty of Science, University of Zagreb, Zagreb (Croatia)

    2012-10-20T23:59:59.000Z

    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].

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

    SciTech Connect (OSTI)

    Weber, Adam; Weber, Adam Z.

    2008-07-30T23:59:59.000Z

    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.

  16. Ultrasonic thickness measurements on corroded steel members: a statistical analysis of error

    E-Print Network [OSTI]

    Konen, Keith Forman

    1999-01-01T23:59:59.000Z

    of the Journal of Structural Engineering, ASCE. This study is the first phase of a joint industry project (JIP) that is funded by the Mineral Management Service of the Department of the Interior, Shell Deepwater Development, Inc. , and Mobil Technology Company... to the numbering system used in the 1989 JIP. Note that not all members were used in this particular study. TABLE 5. 1. Description of specimens Member 10 15 16 Diameter (in) 12. 75 12. 50 12. 75 20. 00 16. 00 14. 00 14. 00 Wall Thickness (in) 0...

  17. Determination of thickness and composition of high-k dielectrics using high-energy electrons

    SciTech Connect (OSTI)

    Grande, P. L. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia) [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia); Instituto de Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Vos, M. [Atomic and Molecular Physics Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)] [Atomic and Molecular Physics Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia); Venkatachalam, D. K.; Elliman, R. G. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)] [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia); Nandi, S. K. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia) [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia); Research School of Astronomy and Astrophysics, The Australian National University, Canberra ACT 2611 (Australia); Department of Physics, University of Chittagong, Chittagong 4331 (Bangladesh)

    2013-08-12T23:59:59.000Z

    We demonstrate the application of high-energy elastic electron backscattering to the analysis of thin (2–20 nm) HfO{sub 2} overlayers on oxidized Si substrates. The film composition and thickness are determined directly from elastic scattering peaks characteristic of each element. The stoichiometry of the films is determined with an accuracy of 5%–10%. The experimental results are corroborated by medium energy ions scattering and Rutherford backscattering spectrometry measurements, and clearly demonstrate the applicability of the technique for thin-film analysis. Significantly, the presented technique opens new possibilities for nm depth profiling with high spatial resolution in scanning electron microscopes.

  18. Monitoring Morphological Changes in 2D Monolayer Semiconductors Using Atom-Thick Plasmonic Nanocavities

    E-Print Network [OSTI]

    Sigle, Daniel O.; Mertens, Jan; Herrmann, Lars O.; Bowman, Richard W.; Ithurria, Sandrine; Dubertret, Benoit; Shi, Yumeng; Yang, Hui Ying; Tserkezis, Christos; Aizpurua, Javier; Baumberg, Jeremy J.

    2014-12-17T23:59:59.000Z

    coupled modes. One weaker mode corresponds to transverse dipolar charge oscillations inside the NP alone (𝑇𝑇).7,9–11 However, the dominant modes shift to the red due to longitudinal coupling between the NP and its image in the mirror surface, forming... -ion-beam milling, mounted on a TEM grid using a nanomanipulator and polished down to a thickness of ~100nm. DF-STEM imaging was performed in a Hitachi S-5500 SEM at 30kV acceleration voltage. Theory simulations: Exact simulations are carried out using...

  19. Influence of film thickness and air exposure on the transport gap of manganese phthalocyanine

    SciTech Connect (OSTI)

    Haidu, F.; Fechner, A.; Salvan, G.; Gordan, O. D.; Fronk, M.; Zahn, D. R. T. [Semiconductor Physics, Chemnitz University of Technology, D-09107 Chemnitz (Germany); Lehmann, D. [Semiconductor Physics, Chemnitz University of Technology, D-09107 Chemnitz (Germany); INNOVENT Technology Development, D-07745 Jena (Germany); Mahns, B.; Knupfer, M. [Electronic and Optical Properties Department, IFW Dresden, D-01171 Dresden (Germany)

    2013-06-15T23:59:59.000Z

    The interface formation between manganese phthalocyanine (MnPc) and cobalt was investigated combining ultraviolet photoelectron spectroscopy and inverse photoelectron spectroscopy. The transport band gap of the MnPc increases with the film thickness up to a value of (1.2 {+-} 0.3) eV while the optical band gap as determined from spectroscopic ellipsometry amounts to 0.5 eV. The gap values are smaller compared to other phthalocyanines due to metallic Mn 3d states close to the Fermi level. The transport band gap was found to open upon air exposure as a result of the disappearance of the occupied 3d electronic states.

  20. 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)

    2014-02-24T23:59:59.000Z

    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.

  1. 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)

    2000-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    ?ahin-Biryol, Derya, E-mail: dsahin@ucmerced.edu; Ilan, Boaz [Applied Mathematics Unit, School of Natural Sciences, University of California Merced, 5200 North Lake Road, Merced, California 95343 (United States)

    2014-06-15T23:59:59.000Z

    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.

  3. Removing the concavity of the thick center vortex potentials by fluctuating the vortex profile

    E-Print Network [OSTI]

    Sedigheh Deldar; Shahnoosh Rafibakhsh

    2010-03-14T23:59:59.000Z

    The thick center vortex model reproduces important aspects of the potentials between static quark sources as seen in lattice Yang-Mills calculations: Both the intermediate distance behavior, governed by Casimir scaling, as well as the long distance behavior, governed by N-ality, are obtained. However, when a fixed vortex profile is used, these two distance regimes do not connect naturally to each other. The transition in general violates concavity constraints on the potential, especially for higher representations of the gauge group. We demonstrate how this issue can be alleviated when the vortex profile is allowed to fluctuate within this simple model.

  4. 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

    2015-01-01T23:59:59.000Z

    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.

  5. Constraining the symmetry energy from the neutron skin thickness of Tin isotopes

    E-Print Network [OSTI]

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

    2011-03-24T23:59:59.000Z

    We show in the Skyrme-Hartree-Fock approach that unambiguous correlations exist between observables of finite nuclei and nuclear matter properties. Using this correlation analysis to existing data on the neutron skin thickness of Sn isotopes, we find important constraints on the value E_{sym}(rho_0) and density slope L of the nuclear symmetry energy at saturation density. Combining these constraints with those from recent analyses of isospin diffusion and double neutron/proton ratio in heavy ion collisions leads to a value of L=58\\pm 18 MeV approximately independent of E_{sym}(\\rho_0).

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

    SciTech Connect (OSTI)

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

    2010-03-31T23:59:59.000Z

    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.

  7. The effect of stratum thickness ratio on crossflow in a stratified petroleum reservoir

    E-Print Network [OSTI]

    Kereluk, Michael Joseph

    1966-01-01T23:59:59.000Z

    , the effect of stratum thickness ratio and viscosity ratio on crossflow were studied. REVIEW OF LITERATURE The possible importance of permeability stratification in a reservoir being waterflooded was first mentioned in a paper by 1 . Lester C. Uren in f... States, API (1950) p. 160-174. 4, Dyes, A. B. and Braun, P. H. : "Sweepout Patterns in De- pleted and Stratified Reservoirs, " Producers Monthl (1954) 19, No. 2, p, 24-30. 5. Gaucher, D. H. and Lindley, D. C. : "Waterflood Performance in a Stratified...

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

    SciTech Connect (OSTI)

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

    2005-01-24T23:59:59.000Z

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

  9. Validated heat-transfer and pressure-drop prediction methods based on the discrete-element method: Phase 2, two-dimensional rib roughness

    SciTech Connect (OSTI)

    James, C.A.; Hodge, B.K.; Taylor, R.P. [Mississippi State Univ., MS (United States). Dept. of Mechanical and Nuclear Engineering

    1993-05-01T23:59:59.000Z

    Surface roughness is a commonly used approach for enhancing the rate of heat transfer of surfaces, such as in heat-exchanger tubes. Because the improved thermal performance of roughened surfaces is at the expense of increased flow resistance (increased pressure drop or friction factor), accurate prediction techniques for determining the friction factors and Nusselt numbers for roughened surfaces are required if such features are to be considered as design options. This report presents the results of the second phase of a research program sponsored by Argonne National Laboratory to validate models for the prediction of friction factors and Nusselt numbers for fully developed turbulent flow in enhanced heat-exchanger tubes. The first phase was concerned with validating a roughness model for turbulent flow in tubes internally roughened with three-dimensional distributed roughness elements, such as sandgrains, spheres, hemispheres, and cones. The second phase is concerned with devising and validating methods for the prediction of friction factors and Nusselt numbers for turbulent flow in tubes internally roughened with repeated, two-dimensional ribs aligned perpendicular to the flow. The ribs are spaced sufficiently far apart that the leeward-side separated flow reattaches to the wall before again separating in order to negotiate the next rib. This heat-transfer enhancement mechanism is called the separation and reattachment mechanism, after Rabas (1989). This work is limited to rectangular rib shapes.

  10. Comprehensive magnetotransport characterization of two dimensional electron gas in AlGaN/GaN high electron mobility transistor structures leading to the assessment of interface roughness

    SciTech Connect (OSTI)

    Mishra, Manna Kumari [Solid State Physics Laboratory, Lucknow Road, Timarpur, Delhi-110054 (India); Netaji Subhas Institute of Technology, Dwarka, New Delhi-110078 (India); Sharma, Rajesh K., E-mail: rksharma@sspl.drdo.in; Manchanda, Rachna; Bag, Rajesh K.; Muralidharan, Rangarajan [Solid State Physics Laboratory, Lucknow Road, Timarpur, Delhi-110054 (India); Thakur, Om Prakash [Netaji Subhas Institute of Technology, Dwarka, New Delhi-110078 (India)

    2014-09-15T23:59:59.000Z

    Magnetotransport in two distinct AlGaN/GaN HEMT structures grown by Molecular Beam Epitaxy (MBE) on Fe-doped templates is investigated using Shubnikov de-Haas Oscillations in the temperature range of 1.8–6 K and multicarrier fitting in the temperature range of 1.8–300 K. The temperature dependence of the two dimensional electron gas mobility is extracted from simultaneous multicarrier fitting of transverse and longitudinal resistivity as a function of magnetic field and the data is utilized to estimate contribution of interface roughness to the mobility and the corresponding transport lifetime. The quantum scattering time obtained from the analysis of Shubnikov de Haas Oscillations in transverse magnetoresistance along with the transport lifetime time were used to estimate interface roughness amplitude and lateral correlation length. The results indicate that the insertion of AlN over layer deposited prior to the growth of GaN base layer on Fe doped GaN templates for forming HEMT structures reduced the parallel conduction but resulted in an increase in interface roughness.

  11. 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

    2005-11-01T23:59:59.000Z

    This thesis presents a multi-purpose sensor concept viable for the simultaneous measurement of pressure, temperature and thickness of plate structures. It also establishes the knowledge base necessary for future sensor ...

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

    Broader source: Energy.gov [DOE]

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

  13. 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

    2005-11-01T23:59:59.000Z

    -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...

  14. Development of automated welding process for field fabrication of thick walled pressure vessels. (First quarterly report, FY 1981)

    SciTech Connect (OSTI)

    Schneider, U.A.

    1981-01-01T23:59:59.000Z

    The choice of sets of root welding parameters is discussed. Thick field demonstration/qualification welds will be performed. A welding procedure handbook which will be prepared is mentioned. (DLC)

  15. 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 ...

  16. 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)

    2012-07-01T23:59:59.000Z

    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)

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

    E-Print Network [OSTI]

    Jianmin Dong; Wei Zuo; Jianzhong Gu

    2015-04-09T23:59:59.000Z

    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

    2015-01-01T23:59:59.000Z

    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. Bandgap Engineering of InP QDs Through Shell Thickness and Composition

    SciTech Connect (OSTI)

    Dennis, Allison M. [Los Alamos National Laboratory; Mangum, Benjamin D. [Los Alamos National Laboratory; Piryatinski, Andrei [Los Alamos National Laboratory; Park, Young-Shin [Los Alamos National Laboratory; Htoon, Han [Los Alamos National Laboratory; Hollingsworth, Jennifer A. [Los Alamos National Laboratory

    2012-06-21T23:59:59.000Z

    Fields as diverse as biological imaging and telecommunications utilize the unique photophysical and electronic properties of nanocrystal quantum dots (NQDs). The development of new NQD compositions promises material properties optimized for specific applications, while addressing material toxicity. Indium phosphide (InP) offers a 'green' alternative to the traditional cadmium-based NQDs, but suffers from extreme susceptibility to oxidation. Coating InP cores with more stable shell materials significantly improves nanocrystal resistance to oxidation and photostability. We have investigated several new InP-based core-shell compositions, correlating our results with theoretical predictions of their optical and electronic properties. Specifically, we can tailor the InP core-shell QDs to a type-I, quasi-type-II, or type-II bandgap structure with emission wavelengths ranging from 500-1300 nm depending on the shell material used (ZnS, ZnSe, CdS, or CdSe) and the thickness of the shell. Single molecule microscopy assessments of photobleaching and blinking are used to correlate NQD properties with shell thickness.

  20. The {alpha}-induced thick-target {gamma}-ray yield from light elements

    SciTech Connect (OSTI)

    Heaton, R.K. [Queen`s Univ., Kingston, ON (Canada). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1994-10-01T23:59:59.000Z

    The {alpha}-induced thick-target {gamma}-ray yield from light elements has been measured in the energy range 5.6 MeV {le} E{sub {alpha}} {le} 10 MeV. The {gamma}-ray yield for > 2.1 MeV from thick targets of beryllium, boron nitride, sodium fluoride, magnesium, aluminum and silicon were measured using the {alpha}-particle beam from the Lawrence Berkeley Laboratories 88 in. cyclotron. The elemental yields from this experiment were used to construct the {alpha}-induced direct production {gamma}-ray spectrum from materials in the SNO detector, a large volume ultra-low background neutrino detector located in the Creighton mine near Sudbury, Canada. This background source was an order of magnitude lower than predicted by previous calculations. These measurements are in good agreement with theoretical calculations of this spectrum based on a statistical nuclear model of the reaction, with the gross high energy spectrum structure being reproduced to within a factor of two. Detailed comparison of experimental and theoretical excitation population distribution of several residual nuclei indicate the same level of agreement within experimental uncertainties.

  1. Collisionless Shocks and TeV Neutrinos before Supernova Shock Breakout from an Optically Thick Wind

    E-Print Network [OSTI]

    Giacinti, G

    2015-01-01T23:59:59.000Z

    During a supernova explosion, a radiation-dominated shock (RDS) travels through its progenitor. A collisionless shock (CS) is usually assumed to replace it during shock breakout (SB). We demonstrate here that for some realistic progenitors enshrouded in optically thick winds, such as possibly SN 2008D, a CS forms deep inside the wind, soon after the RDS leaves the core, and therefore significantly before SB. The RDS does not survive the transition from the core to the thick wind when the wind close to the core is not sufficiently dense to compensate for the $r^{-2}$ dilution of photons due to shock curvature. This typically happens when the shock velocity is $\\lesssim 0.1 {\\rm c} \\, (\\frac{u_{\\rm w}}{10\\,{\\rm km/s}}) (\\frac{\\dot{M}}{5 \\cdot 10^{-4} \\, {\\rm M}_\\odot {\\rm /yr}})^{-1} (\\frac{r_\\ast}{10^{13}\\,{\\rm cm}})$, where $u_{\\rm w}$, $\\dot{M}$ and $r_\\ast$ are respectively the wind velocity, mass-loss rate and radius of the progenitor star. The radiative CS results in a hard spectrum of the photon flash at...

  2. Using Neutron Star Observations to Determine Crust Thicknesses, Moments of Inertia, and Tidal Deformabilities

    E-Print Network [OSTI]

    Andrew W. Steiner; Stefano Gandolfi; Farrukh J. Fattoyev; William G. Newton

    2015-01-25T23:59:59.000Z

    We perform a systematic assessment of models for the equation of state (EOS) of dense matter in the context of recent neutron star mass and radius measurements to obtain a broad picture of the structure of neutron stars. We demonstrate that currently available neutron star mass and radius measurements provide strong constraints on moments of inertia, tidal deformabilities, and crust thicknesses. A measurement of the moment of inertia of PSR J0737-3039A with 10% error, without any other information from observations, will constrain the EOS over a range of densities to within 50%$-$60%. We find tidal deformabilities between 0.6 and $6\\times 10^{36}$ g cm$^{2}$ s$^{2}$ (to 95% confidence) for $M=1.4~\\mathrm{M}_{\\odot}$, and any measurement which constrains this range will provide an important constraint on dense matter. The crustal fraction of the moment of inertia can be as large as 10% for $M=1.4~\\mathrm{M}_{\\odot}$ permitting crusts to have a large enough moment of inertia reservoir to explain glitches in the Vela pulsar even with a large amount of superfluid entrainment. Finally, due to the uncertainty in the equation of state, there is at least a 40% variation in the thickness of the crust for a fixed mass and radius, which implies that future simulations of the cooling of a neutron star crust which has been heated by accretion will need to take this variation into account.

  3. Symmetry energy at subsaturation densities and the neutron skin thickness of 208Pb

    E-Print Network [OSTI]

    Fan, Xiaohua; Zuo, Wei

    2015-01-01T23:59:59.000Z

    The mass-dependent symmetry energy coefficients $a_{sym}(A)$ has been extracted by analysing the heavy nuclear mass differences reducing the uncertainties as far as possible in our previous work. Taking advantage of the obtained symmetry energy coefficient $a_{sym}(A)$ and the density profiles obtained by switching off the Coulomb interaction in $^{208}\\text{Pb}$, we calculated the slope parameter $L_{0.11}$ of the symmetry energy at the density of $0.11\\text{fm}^{-3}$. The calculated $L_{0.11}$ ranges from 40.5 MeV to 60.3 MeV. The slope parameter $L_{0.11}$ of the symmetry energy at the density of $0.11\\text{fm}^{-3}$ is also calculated directly with Skyrme interactions for nuclear matter and is found to have a fine linear relation with the neutron skin thickness of $^{208}\\text{Pb}$, which is the difference of the neutron and proton rms radii of the nucleus. With the linear relation the neutron skin thickness $ \\Delta R_{np} $ of $^{208}\\text{Pb}$ is predicted to be 0.15 - 0.21 fm.

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

    SciTech Connect (OSTI)

    Svirski, Gilad; Nakar, Ehud, E-mail: swirskig@post.tau.ac.il [Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel)

    2014-06-20T23:59:59.000Z

    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.

  5. Vacuum densities for a thick brane in AdS spacetime

    E-Print Network [OSTI]

    A. A. Saharian; A. L. Mkhitaryan

    2007-10-18T23:59:59.000Z

    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.

  6. Temperature inversion on the surface of externally heated optically thick multigrain dust clouds

    E-Print Network [OSTI]

    Dejan Vinkovic

    2006-12-01T23:59:59.000Z

    It was recently discovered that the temperature in the surface layer of externally heated optically thick gray dust clouds increases with the optical depth for some distance from the surface, as opposed to the normal decrease in temperature with distance in the rest of the cloud. This temperature inversion is a result of efficient absorption of diffuse flux from the cloud interior by the surface dust exposed to the external radiation. A micron or bigger size grains experience this effect when the external flux is of stellar spectrum. We explore what happens to the effect when dust is a mixture of grain sizes (multigrain). Two possible boundary conditions are considered: i) a constant external flux without constrains on the dust temperature, and ii) the maximum dust temperature set to the sublimation temperature. We find that the first condition allows small grains to completely suppress the temperature inversion of big grains if the overall opacity is dominated by small grains. The second condition enables big grains to maintain the inversion even when they are a minor contributor to the opacity. In reality, the choice of boundary condition depends on the dust dynamics. When applied to the physics of protoplanetary disks, the temperature inversion leads to a previously unrecognized disk structure where optically thin dust can exist inside the dust destruction radius of an optically thick disk. We conclude that the transition between the dusty disk and the gaseous inner clearing is not a sharp edge, but rather a large optically thin region.

  7. Co layer thickness dependence of exchange biasing for IrMnCo and FeMnCo

    E-Print Network [OSTI]

    Reilly, Anne

    Co layer thickness dependence of exchange biasing for IrMnÕCo and FeMnÕCo K. A. Seua) and H. Huang) in IrMn/Co and FeMn/Co bilayers using the magneto-optical Kerr effect. Samples are sputtered wedges on silicon with Co thicknesses ranging from 1 to 17 nm. The IrMn/Co with exchange bias interface energy of 0

  8. 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)

    2014-12-01T23:59:59.000Z

    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.

  9. Ice Thickness Measurements of the Southwest Greenland 2000-m Contour Line J. J. Legarsky, S.P. Gogineni, P. Kanagaratnam, T. L. Akins and Y. C. Wong

    E-Print Network [OSTI]

    Kansas, University of

    Ice Thickness Measurements of the Southwest Greenland 2000-m Contour Line J. J. Legarsky, S Laborato~ performed ice thickness measurements along several flights in the southern part of Greenland. We of the Greenland. INTRODUCTION Since 1993, we have been performing radar ice thickness measurements as a part

  10. Technical Note: Skin thickness measurements using high-resolution flat-panel cone-beam dedicated breast CT

    SciTech Connect (OSTI)

    Shi Linxi; Vedantham, Srinivasan; Karellas, Andrew [Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655 (United States); O'Connell, Avice M. [Department of Radiology, University of Rochester Medical Center, Rochester, New York 14642 (United States)

    2013-03-15T23:59:59.000Z

    Purpose: To determine the mean and range of location-averaged breast skin thickness using high-resolution dedicated breast CT for use in Monte Carlo-based estimation of normalized glandular dose coefficients. Methods: This study retrospectively analyzed image data from a clinical study investigating dedicated breast CT. An algorithm similar to that described by Huang et al.['The effect of skin thickness determined using breast CT on mammographic dosimetry,' Med. Phys. 35(4), 1199-1206 (2008)] was used to determine the skin thickness in 137 dedicated breast CT volumes from 136 women. The location-averaged mean breast skin thickness for each breast was estimated and the study population mean and range were determined. Pathology results were available for 132 women, and were used to investigate if the distribution of location-averaged mean breast skin thickness varied with pathology. The effect of surface fitting to account for breast curvature was also studied. Results: The study mean ({+-} interbreast SD) for breast skin thickness was 1.44 {+-} 0.25 mm (range: 0.87-2.34 mm), which was in excellent agreement with Huang et al. Based on pathology, pair-wise statistical analysis (Mann-Whitney test) indicated that at the 0.05 significance level, there were no significant difference in the location-averaged mean breast skin thickness distributions between the groups: benign vs malignant (p= 0.223), benign vs hyperplasia (p= 0.651), hyperplasia vs malignant (p= 0.229), and malignant vs nonmalignant (p= 0.172). Conclusions: Considering this study used a different clinical prototype system, and the study participants were from a different geographical location, the observed agreement between the two studies suggests that the choice of 1.45 mm thick skin layer comprising the epidermis and the dermis for breast dosimetry is appropriate. While some benign and malignant conditions could cause skin thickening, in this study cohort the location-averaged mean breast skin thickness distributions did not differ significantly with pathology. The study also underscored the importance of considering breast curvature in estimating breast skin thickness.

  11. Oscillations with Co and Cu thickness of the current-perpendicular-to-plane giant magnetoresistance of a Co/Cu/Co,,001... trilayer

    E-Print Network [OSTI]

    Umerski, Andrey

    located at the ferromagnet/spacer inter- faces interfacial roughness . However, a fully quantitative current-in-plane geom- etry, the dimensions of the sample in the direction of the current are always

  12. Nonlinear signal transformation in thickness gauging with multiple ionizing-radiation detectors

    SciTech Connect (OSTI)

    Nedavnii, O.I.

    1988-06-01T23:59:59.000Z

    A maximum signal-to-noise ratio criterion has been established for the conversion of information weights for summed signals in a multidetector device for thickness gauging on sheet materials using a beam of monoenergetic photons with a given attenuation coefficient and a set of detectors with a given configuration. The source field in the detector zone is taken as uniform in the absence of the absorber. A secant transformation is used in the source use factor. The advantage of this optimal conversion is estimated. In using the multidetector system in sheet material gauging to obtain corrections for composition variations the source requirement is either a nuclide with a compound photon spectrum or a set of nuclides such as Am 241 and Co 57.

  13. 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.

    2010-09-01T23:59:59.000Z

    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.

  14. Effect of Monolayer Thickness Fluctuations on Coherent Exciton Coupling in Single Quantum Wells

    E-Print Network [OSTI]

    Yuri D. Glinka; Zheng Sun; Mikhail Erementchouk; Michael N. Leuenberger; Alan D. Bristow; Steven T. Cundiff; Allan S. Bracker; Xiaoqin Li

    2012-10-04T23:59:59.000Z

    Monolayer fluctuations in the thickness of a semiconductor quantum well (QW) lead to three types of excitons, located in the narrower, average and thicker regions of the QW, which are clearly resolved in optical spectra. Whether or not these excitons are coherently coupled via Coulomb interactions is a long-standing debate. We demonstrate that different types of disorder in QWs distinctly affects the coherent coupling and that the coupling strength can be quantitatively measured using optical two-dimensional Fourier transform spectroscopy. We prove experimentally and theoretically that in narrow quantum wells the coherent coupling occurs predominantly between excitons residing in the disorder-free areas of the QWs and those residing in the plateau-type disorder. In contrast, excitons localized in the fault-type disorder potentials do not coherently couple to other excitons.

  15. Correspondence Between Magnetoresistance and Magnetization in Co/Cu Multilayers Studied at Higher Spacer Layer Thickness

    SciTech Connect (OSTI)

    Patil, P. B.; Kumar, M. Senthil [Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Aswal, D. K.; Gupta, S. K. [Technical Physics and Prototype Engineering Division, BARC, Mumbai 400085 (India)

    2010-12-01T23:59:59.000Z

    A series of [Cu(t{sub Cu})/Co(25 A)]{sub 25} multilayers at higher spacer layer thickness have been deposited by dc magnetron sputtering. Magnetoresistance (MR) measurements have been carried out at different temperatures. MR curves showed hysteresis by displaying peaks at magnetic field H{sub p}. The field values exhibiting the maximum resistance in the magnetoresistance curve (H{sub p}) were greater than the coercivity (H{sub c}). The correspondence between the shape of the MR curve and that of the magnetization curve has been established and observed peak splitting in MR curves is attributed to a hardening in the magnetization reversal of some magnetic grains.

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

    DOE Patents [OSTI]

    Burdgick, Steven Sebastian (Schenectady, NY)

    2002-01-01T23:59:59.000Z

    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.

  17. 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)

    1996-01-01T23:59:59.000Z

    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.

  18. Calculation of shielding door thicknesses for radiation therapy facilities using the ITS Monte Carlo program

    SciTech Connect (OSTI)

    Biggs, P.J. (Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston (United States))

    1991-10-01T23:59:59.000Z

    Shielding calculations for door thicknesses for megavoltage radiotherapy facilities with mazes are generally straightforward. To simplify the calculations, the standard formalism adopts several approximations relating to the average beam path, scattering coefficients, and the mean energy of the spectrum of scattered radiation. To test the accuracy of these calculations, the Monte Carlo program, ITS, was applied to this problem by determining the dose and energy spectrum of the radiation at the door for 4- and 10-MV bremsstrahlung beams incident on a phantom at isocenter. This was performed for mazes, one termed 'standard' and the other a shorter maze where the primary beam is incident on the wall adjacent to the door. The peak of the photon-energy spectrum at the door was found to be the same for both types of maze, independent of primary beam energy, and also, in the case of the conventional maze, of the primary beam orientation. The spectrum was harder for the short maze and for 10 MV vs. 4 MV. The thickness of the lead door for a short maze configuration was 1.5 cm for 10 MV and 1.2 cm for 4 MV vs. approximately less than 1 mm for a conventional maze. For the conventional maze, the Monte Carlo calculation predicts the dose at the door to be lower than given by NCRP 49 and NCRP 51 by about a factor of 2 at 4 MV but to be the same at 10 MV. For the short maze, the Monte Carlo predicts the dose to be a factor of 3 lower for 4 MV and about a factor of 1.5 lower for 10 MV. Experimental results support the Monte Carlo findings for the short maze.

  19. The runaway instability of thick discs around black holes. II. Non constant angular momentum discs

    E-Print Network [OSTI]

    Frederic Daigne; Jose A. Font

    2003-11-28T23:59:59.000Z

    We present results from a comprehensive number of relativistic, time-dependent, axisymmetric simulations of the runaway instability of non-constant angular momentum thick discs around black holes. This second paper extends earlier results where only constant angular momentum discs were considered. All relevant aspects of the theory of stationary thick discs around rotating black holes, necessary to build the initial state in our simulations, are presented in great detail. The angular momentum of the discs is assumed to increase outwards with the radial distance according to a power law. The main simplifying assumptions of our approach are not to include magnetic fields and self-gravity in the discs. Furthermore, the dynamics of the spacetime is accounted for by computing the transfer of mass and angular momentum from the disc to the black hole through the event horizon : the evolution of the central black hole is assumed to follow a sequence of Kerr black holes of increasing mass and spin. In agreement with previous results based on stationary models we find that by allowing the mass and the spin of the black hole to grow, constant angular momentum discs rapidly become unstable on a dynamical timescale. The comparison with the results of paper I shows that the effect of the angular momentum transfer from the torus to the black hole is to make constant angular momentum discs less unstable, increasing the timescale of the instability. However, we find that non-constant angular momentum discs are dramatically stabilized for very small values of the angular momentum slope. Our time-dependent simulations confirm, thus, the predictions of stationary studies concerning the stabilizing effect of non-constant angular momentum distributions.

  20. The determination of the turbulent intensities in a transitional flow from a smooth to a rough wall with zero pressure gradient in a two-dimensional channel

    E-Print Network [OSTI]

    Islam, Obaidul

    1963-01-01T23:59:59.000Z

    THE DETERMINATION OF THE TURBULENT INTENSITIES IN A TRANSITIONAL FLOW FROM A SMOOTH TO A ROUGH WALL WITH ZERO PRESSURE GRADIENT IN A TWO-DIMENSIONAL CHANNEL A Thesis By Ol3AIDU I. ISLAM Submitted to the Graduate School of. tire Agricultural... WALL WITH ZERO PRESSURE GRADIENT IN A TWO DIMENSIONAL. GHANNEL A Thesis By OBAIDUL ISLAM Approved as to style and content by: F / F Ghairma p'f mm tg Head of Department May 1963 ACKNOWLEDGMENTS Grateful acknowledgment is made to the Texas...

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

    SciTech Connect (OSTI)

    Wang, Tianqi; Ganguly, Koustav; Marshall, Patrick; Xu, Peng; Jalan, Bharat [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)] [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2013-11-18T23:59:59.000Z

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

  2. The effect of fiber coating thickness on the interfacial properties of a continuous fiber ceramic matrix composite

    SciTech Connect (OSTI)

    Lara-Curzio, E.; Ferber, M.K.; Lowden, R.A.

    1994-09-01T23:59:59.000Z

    The interfacial properties (coefficient of friction, residual clamping stress, residual axial stress, and debond stress) of a continuous fiber ceramic composite were determined by means of single-fiber push-out tests. The composite consisted of Nicalon{trademark} fibers, that had been coated prior to matrix infiltration with carbon layers ranging in thickness from 0.03 to 1.2 {mu}m, and a SiC matrix. It was found that the effective interfacial frictional stress decreased as the thickness of the carbon layer increased, from 24.6 {plus_minus} 9.9 MPa for a thickness of 0.03 Jim to 5.8 {plus_minus} 1.4 MPa for a thickness of 1.25 {mu}m. It was also found that both the coefficient of friction and the residual clamping stress decreased as the thickness of the carbon layer increased. These results are explained in terms of the state of residual stresses in this composite and the role of the fiber surface topography during fiber sliding.

  3. Free radially expanding liquid sheet in air: time- and space-resolved measurement of the thickness field

    E-Print Network [OSTI]

    Clara Vernay; Laurence Ramos; Christian Ligoure

    2014-12-12T23:59:59.000Z

    The collision of a liquid drop against a small target results in the formation of a thin liquid sheet that extends radially until it reaches a maximum diameter. The subsequent retraction is due to the air-liquid surface tension. We have used a time- and space-resolved technique to measure the thickness field of this class of liquid sheet, based on the grey level measurement of the image of a dyed liquid sheet recorded using a fast camera. This method enables a precise measurement of the thickness in the range $(10-450) \\, \\mathrm{\\mu m}$, with a temporal resolution equal to that of the camera. We have measured the evolution with time since impact, $t$, and radial position, $r$, of the thickness, $h(r,t)$, for various drop volumes and impact velocities. Two asymptotic regimes for the expansion of the sheet are evidenced. The scalings of the thickness with $t$ and $r$ measured in the two regimes are those that were predicted in \\citet{Rozhkov2004} fort the short-time regime and \\citet{Villermaux2011} for the long time regime, but never experimentally measured before. Interestingly, our experimental data also evidence the existence of a maximum of the film thickness $h_{\\rm{max}}(r)$ at a radial position $r_{\\rm{h_{max}}}(t)$ corresponding to the crossover of these two asymptotic regimes. The maximum moves with a constant velocity of the order of the drop impact velocity, as expected theoretically. Thanks to our visualization technique, we also evidence an azimuthal thickness modulation of the liquid sheets.

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

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

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

    2014-12-01T23:59:59.000Z

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

  5. Impact of surface roughness on the electrical parameters of industrial high efficiency NaOH-NaOCl textured multicrystalline silicon solar cell

    SciTech Connect (OSTI)

    Basu, P.K. [Department of Physics, Echelon Institute of Technology, Faridabad 121002, Haryana (India); Pujahari, R.M. [Department of Physics, Echelon Institute of Technology, Faridabad 121002, Haryana (India); Department of Physics, Manav Rachna International University, Faridabad 121001, Haryana (India); Kaur, Harpreet [Department of Physics, Manav Rachna International University, Faridabad 121001, Haryana (India); Department of Physics, Advanced Institute of Technology and Management, Palwal 121105, Haryana (India); Singh, Devi [Department of Physics, Manav Rachna International University, Faridabad 121001, Haryana (India); Varandani, D.; Mehta, B.R. [Department of Physics, Indian Institute of Technology, New Delhi 110016 (India)

    2010-09-15T23:59:59.000Z

    Sodium hydroxide (NaOH) and sodium hypochlorite (NaOCl) solution (1:1 ratio by volume) based texturization process at 80-82 C is an easy, low cost and comparatively new and convenient option for fabrication of any multicrystalline silicon (mC-Si) solar cell. In the present study atomic force microscope is used to observe the intragrain surface in a miniscule area (3 {mu}m x 3 {mu}m) of NaOH-NaOCl textured surface by two and three dimensional analysis, roughness analysis and section analysis. The r.m.s value of the surface parameter of 7.0 nm ascertains the smoothness of the textured surface and further the surface reflectivity is minimized to 4-6% in the 500-1000 nm wavelength range by a proper silicon nitride anti-reflection coating. Comparing with the standard HF-HNO{sub 3}-CH{sub 3}COOH acid textured cell, the NaOH-NaOCl textured cell shows a comparatively lower value of series resistance of 7.17 m{omega}, higher value of shunt resistance of 18.4 {omega} to yield a fill factor of 0.766 leading to more than 15% cell efficiency in the industrial cell processing line. This AFM study yields different surface roughness parameters for the NaOH-NaOCl textured wafers which can be used as a reference standard for optimized texturing. (author)

  6. Effect of roof slope and thickness on the performance of a saltstone vault

    SciTech Connect (OSTI)

    Yu, A.D.; Lam, Poh-Sang; Hsu, R.H.

    1995-09-01T23:59:59.000Z

    At the Savannah River Site, low-level radioactive decontaminated salt solution is mixed with slag, flyash, and cement to form a grout-like material called ``Saltstone.`` The Saltstone is poured into concrete vaults constructed at the Saltstone Disposal Facility (SDF). The SDF is designed for the release of contaminants in a slow, controlled manner over thousands of years. The impact of SDF on groundwater has been studied in a radiological performance assessment (PA). Groundwater models were used to predict the fluid flow and contaminant transport at SDF. The models predicted a spatial contaminant concentration distribution in groundwater as a function of time. This study focuses on the roof configuration of Saltstone vault, with special interests in cost-effectiveness. We conducted a study to evaluate the effect of roof slope and thickness on the performance of a Saltstone vault. Four roof configurations were simulated. The tool used for the simulation was ECLIPSE, a finite-difference petroleum reservoir engineering code with an environmental tracer option. Nitrate was used as the ``tracer`` contaminant. In this study, ECLIPSE solves the two-phase two-dimensional flow and transport problem up to 10,000 years. This paper describes a modeling study used to evaluate roof design options for the Saltstone vault.

  7. 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

    2007-06-08T23:59:59.000Z

    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.

  8. 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.

    1983-04-01T23:59:59.000Z

    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.

  9. Codes for optically thick and hot photoionized media - Radiative transfer and new developments

    E-Print Network [OSTI]

    Anne-Marie Dumont; Suzy Collin

    2001-03-20T23:59:59.000Z

    We describe a code designed for hot media {(T $\\ge$} a few 10$^4$ K), optically thick to Compton scattering. It computes the structure of a plane-parallel slab of gas in thermal and ionization equilibrium, illuminated on one side or on both sides by a given spectrum. This code has been presented in a previous paper (Dumont, Abrassart & Collin 2000), where several aspects were already discussed. So we focus here mainly on the recent developments. Presently the code solves the transfer of the continuum with the Accelerated Lambda Iteration method (ALI) and that of the lines in a two stream Eddington approximation, without using the local escape probability formalism to approximate the line transfer. This transfer code is coupled with a Monte Carlo code which allows to take into account direct and inverse Compton diffusions, and to compute the spectrum emitted up to MeV energies, in any geometry. The influence of a few physical parameters is shown, and the importance of the density and pressure distribution (constant density, pressure equilibrium, or hydrostatic equilibrium) is stressed. Recent improvements in the treatment of the atomic data are described, and foreseen developments are mentioned.

  10. 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

    2013-06-28T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Warner, Jacob A.; Gladkis, Laura G.; Timmers, Heiko [School of Physical, Environmental and Mathematical Sciences, University of New South Wales at the Australian Defence Force Academy, Canberra ACT 2602 (Australia); Fitzsimmons, Kathryn E. [Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, D-04103 Leipzig (Germany); Reynolds, Eva M. [Research School of Earth Sciences, Australian National University, Canberra ACT 0200 (Australia)

    2011-06-01T23:59:59.000Z

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

  12. Adaptive Projection Subspace Dimension for the Thick-Restart Lanczos Method

    SciTech Connect (OSTI)

    Yamazaki, Ichitaro; Bai, Zhaojun; Simon, Horst; Wang, Lin-Wang; Wu, K.

    2008-10-01T23:59:59.000Z

    The Thick-Restart Lanczos (TRLan) method is an effective method for solving large-scale Hermitian eigenvalue problems. However, its performance strongly depends on the dimension of the projection subspace. In this paper, we propose an objective function to quantify the effectiveness of a chosen subspace dimension, and then introduce an adaptive scheme to dynamically adjust the dimension at each restart. An open-source software package, nu-TRLan, which implements the TRLan method with this adaptive projection subspace dimension is available in the public domain. The numerical results of synthetic eigenvalue problems are presented to demonstrate that nu-TRLan achieves speedups of between 0.9 and 5.1 over the static method using a default subspace dimension. To demonstrate the effectiveness of nu-TRLan in a real application, we apply it to the electronic structure calculations of quantum dots. We show that nu-TRLan can achieve speedups of greater than 1.69 over the state-of-the-art eigensolver for this application, which is based on the Conjugate Gradient method with a powerful preconditioner.

  13. Localization and quasilocalization of spin-$1/2$ fermion field on two-field thick braneworld

    E-Print Network [OSTI]

    Heng Guo; Qun-Ying Xie; Chun-E. Fu

    2014-08-24T23:59:59.000Z

    Localization of a spin-$1/2$ fermion on the braneworld is an important and interesting problem. It is well known that a five-dimensional free massless fermion $\\Psi$ minimally coupled to gravity cannot be localized on the Randall-Sundrum braneworld. In order to trap such a fermion, the coupling between the fermion and bulk scalar fields should be introduced. In this paper, localization and quasilocalization of a bulk fermion on the thick braneworld generated by two scalar fields (a kink scalar $\\phi$ and a dilaton scalar $\\pi$) are investigated. Two types of couplings between the fermion and two scalars are considered. One coupling is the usual Yukawa coupling $-\\eta\\bar{\\Psi}\\phi\\Psi$ between the fermion and kink scalar, another one is $\\lambda\\bar{\\Psi}\\Gamma^{M}\\partial_{M}\\pi\\gamma^{5}\\Psi$ between the fermion and dilaton scalar. The left-chiral fermion zero mode can be localized on the brane, and both the left- and right-chiral fermion massive Kaluza-Klein modes may be localized or quasilocalized. Hence the four-dimensional massless left-chiral fermion and massive Dirac fermions, whose lifetime is infinite or finite, can be obtained on the brane.

  14. Fracture assessment of weld material from a full-thickness clad RPV shell segment

    SciTech Connect (OSTI)

    Keeney, J.A.; Bass, B.R.; McAfee, W.J.

    1996-07-01T23:59:59.000Z

    Fracture analysis was applied to full-thickness clad beam specimens containing shallow cracks in material for which metallurgical conditions are prototypic of those found in reactor pressure vessels (RPV) at beginning of life. The beam specimens were fabricated from a section of an RPV wall (removed from a canceled nuclear plant) that includes weld, plate, and clad material. Metallurgical factors potentially influencing fracture toughness for shallow cracks in the beam specimens include gradients of material properties and residual stresses due to welding and cladding applications. Fracture toughness estimates were obtained from load vs load-line displacement and load vs crack-mouth-opening displacement data using finite-element methods and estimation schemes based on the {eta}-factor method. One of the beams experienced a significant amount of precleavage stable ductile tearing. Effects of precleavage tearing on estimates of fracture toughness were investigated using continuum damage models. Fracture toughness results from the clad beam specimens were compared with other deep- and shallow-crack single-edge notch bend (SENB) data generated previously from A533 Grade B plate material. Range of scatter for the clad beam data is consistent with that from the laboratory-scale SENB specimens tested at the same temperature.

  15. Influence of neutron-skin thickness on $?^{-}/?^{+}$ ratio in Pb+Pb collisions

    E-Print Network [OSTI]

    Gao-Feng Wei; Bao-An Li; Jun Xu; Lie-Wen Chen

    2015-01-21T23:59:59.000Z

    Within an isospin- and momentum-dependent transport model IBUU11 using as an input nucleon density profiles from Hartree-Fock calculations based on a modified Skyrme-like (MSL) model, we study the influence of the uncertainty of the neutron skin thickness on the $\\pi^{-}/\\pi^{+}$ ratio in both central and peripheral Pb+Pb collisions at beam energies of 400 MeV/nucleon and 1000 MeV/nucleon. Within the current experimental uncertainty range of neutron skin in $^{208}$Pb, while the neutron skin effect on the \\rpi ratio is negligible in central reactions at both energies, it increases gradually with increasing impact parameter and becomes comparable with or even larger than the symmetry energy effect in peripheral collisions especially at 400 MeV/nucleon. Moreover, we found that while the \\rpi ratio is larger with a softer \\esym in central collisions, above certain impact parameters depending on the size of the neutron skin, a stiffer \\esym can lead to a larger \\rpi ratio as most of the pions are produced at densities below the saturation density in these peripheral reactions. Thus, a clear impact parameter selection is important to extract reliable information about the \\esym at suprasaturation densities (size of neutron skin) from the $\\pi^-/\\pi^+$ ratio in central (peripheral) heavy-ion collisions.

  16. Radial mixing and the transition between the thick and thin Galactic discs

    E-Print Network [OSTI]

    Misha Haywood

    2008-05-13T23:59:59.000Z

    The analysis of the kinematics of solar neighbourhood stars shows that the low and high metallicity tails of the thin disc are populated by objects which orbital properties suggest an origin in the outer and inner galactic disc, respectively. Signatures of radial migration are identified in various recent samples, and are shown to be responsible for the high metallicity dispersion in the age-metallicity distribution. Most importantly, it is shown that the population of low metallicity wanderers of the thin disc (-0.7disc (which terminal metallicity is about -0.2 dex). It implies that the thin disc at the solar circle has started to form stars at about this same metallicity. This is also consistent with the fact that 'transition' objects, which have alpha-element abundance intermediate between that of the thick and thin discs, are found in the range [-0.4,-0.2] dex. Once the metal-poor thin disc stars are recognised for what they are - wanderers from the outer thin disc - the parenthood between the two discs can be identified on stars genuinely formed at the solar circle through an evolutionary sequence in [alpha/Fe] and [Fe/H] . Another consequence is that stars that can be considered as truly resulting of the chemical evolution at the solar circle have a metallicity restricted to about [-0.2,+0.2] dex, confirming an old idea that most chemical evolution in the Milky Way have preceded the thin disc formation.

  17. Two-port multimode interference reflectors based on aluminium mirrors in a thick SOI platform

    E-Print Network [OSTI]

    Fandiño, Javier S; Muñoz, Pascual

    2015-01-01T23:59:59.000Z

    Multimode interference reflectors (MIRs) were recently introduced as a new type of photonic integrated devices for on-chip, broadband light reflection. In the original proposal, different MIRs were demonstrated based on total internal reflection mirrors made of two deep-etched facets. Although simpler to fabricate, this approach imposes certain limits on the shape of the field pattern at the reflecting facets, which in turn restricts the types of MIRs that can be implemented. In this work, we propose and experimentally demonstrate the use of aluminium-based mirrors for the design of 2-port MIRs with variable reflectivity. These mirrors do not impose any restrictions on the incident field, and thus give more flexibility at the design stage. Different devices with reflectivities between~0~and~0.5 were fabricated in a 3~um thick SOI platform, and characterization of multiple dies was performed to extract statistical data about their performance. Our measurements show that, on average, losses both in the aluminiu...

  18. 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

  19. 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

  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.

    2005-01-01T23:59:59.000Z

    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. 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, the State University of New Jersey, Piscataway, NJ 08854, USA c Laboratory of Optical Fiber Technology, UMCS, Lublin, 20031, Poland, ABSTRACT Specialty optical fibers operating in harsh aerospace environments

  2. Tooling Factor Calculation In order to yield a more accurate indication of a deposited film's thickness, the rate

    E-Print Network [OSTI]

    Kim, Philip

    Tooling Factor Calculation In order to yield a more accurate indication of a deposited film's thickness, the rate monitor's tooling factor attempts to compensate for necessary differences member before changing an established tooling factor. 1. Position a sample, masked on a half

  3. tions (Fig. 4). The layer thicknesses observed (a 0.90 m for the 400-m fibers; a

    E-Print Network [OSTI]

    Romanowicz, Barbara

    geometry. References and Notes 1. P. Yeh, A. Yariv, E. Marom, J. Opt. Soc. Am. 68, 1196 (1978). 2. J. W. D. Joannopoulos, Opt. Lett. 23, 1573 (1998). 7. P. Yeh, A. Yariv, C. Hong, J. Opt. Soc. Am. 67, 423tions (Fig. 4). The layer thicknesses observed (a 0.90 m for the 400- m fibers; a 0.45 m

  4. 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

  5. High strain rate metalworking with vaporizing foil actuator: Control of flyer velocity by varying input energy and foil thickness

    SciTech Connect (OSTI)

    Vivek, A., E-mail: vivek.4@osu.edu; Hansen, S. R.; Daehn, Glenn S. [Department of Materials Science and Engineering, The Ohio State University, 2041, College Road, Columbus, Ohio 43210 (United States)

    2014-07-15T23:59:59.000Z

    Electrically driven rapid vaporization of thin metallic foils can generate a high pressure which can be used to launch flyers at high velocities. Recently, vaporizing foil actuators have been applied toward a variety of impulse-based metal working operations. In order to exercise control over this useful tool, it is imperative that an understanding of the effect of characteristics of the foil actuator on its ability for mechanical impulse generation is developed. Here, foil actuators made out of 0.0508 mm, 0.0762 mm, and 0.127 mm thick AA1145 were used for launching AA2024-T3 sheets of thickness 0.508 mm toward a photonic Doppler velocimeter probe. Launch velocities ranging between 300 m/s and 1100 m/s were observed. In situ measurement of velocity, current, and voltage assisted in understanding the effect of burst current density and deposited electrical energy on average pressure and velocity with foil actuators of various thicknesses. For the pulse generator, geometry, and flyer used here, the 0.0762 mm thick foil was found to be optimal for launching flyers to high velocities over short distances. Experimenting with annealed foil actuators resulted in no change in the temporal evolution of flyer velocity as compared to foil actuators of full hard temper. A physics-based analytical model was developed and found to have reasonable agreement with experiment.

  6. 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

  7. Thickness distribution of a cooling pyroclastic flow deposit on Augustine Volcano, Alaska: Optimization using InSAR,

    E-Print Network [OSTI]

    Thickness distribution of a cooling pyroclastic flow deposit on Augustine Volcano, Alaska of Volcanology and Geothermal Research 150 (2006) 186­201 www.elsevier.com/locate/jvolgeores #12;imagery have al., 2001), poroelastic rebound (Peltzer et al., 1996), cooling lava (Stevens et al., 2001

  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. Influence of Cloud-Top Height and Geometric Thickness on a MODIS Infrared-Based Ice Cloud Retrieval

    E-Print Network [OSTI]

    Baum, Bryan A.

    of the net cloud radiative forc- ing of these clouds requires a global, diurnal climatology, which can most and temporal scales. In this study, the sensitivity of an infrared-based ice cloud retrieval to effective cloud temperature is investigated, with a focus on the effects of cloud-top height and geometric thickness

  10. Acceptance testing of the eddy current probes for measurement of aluminum hydroxide coating thickness on K West Basin fuel elements

    SciTech Connect (OSTI)

    Pitner, A.L.

    1998-08-21T23:59:59.000Z

    During a recent visual inspection campaign of fuel elements stored in the K West Basin, it was noted that fuel elements contained in sealed aluminum canisters had a heavy translucent type coating on their surfaces (Pitner 1997a). Subsequent sampling of this coating in a hot cell (Pitner 1997b) and analysis of the material identified it as aluminum hydroxide. Because of the relatively high water content of this material, safety related concerns are raised with respect to long term storage of this fuel in Multi-Canister Overpacks (MCOs). A campaign in the basin is planned to demonstrate whether this coating can be removed by mechanical brushing (Bridges 1998). Part of this campaign involves before-and-after measurements of the coating thickness to determine the effectiveness of coating removal by the brushing machine. Measurements of the as-deposited coating thickness on multiple fuel elements are also expected to provide total coating inventory information needed for MCO safety evaluations. The measurement technique must be capable of measuring coating thicknesses on the order of several mils, with a measurement accuracy of 0.5 mil. Several different methods for quantitatively measuring these thin coatings were considered in selecting the most promising approach. Ultrasonic measurement was investigated, but it was determined that due to the thin coating depth and the high water content of the material, the signal would likely pass directly through to the cladding without ever sensing the coating surface. X-ray fluorescence was also identified as a candidate technique, but would not work because the high gamma background from the irradiated fuel would swamp out the low energy aluminum signal. Laser interferometry could possibly be applied, but considerable development would be required and it was considered to be high risk on a short term basis. The consensus reached was that standard eddy current techniques for coating thickness measurement had the best chance for success in this endeavor. If proper placement and alignment of the eddy current measurement probe on the coating could be achieved, the thickness of this non-conductive coating over the conductive fuel cladding (Zircaloy 2) should be measurable based on magnetic stand-off aspects. Eddy current devices are routinely used to measure paint coating thicknesses on metal surfaces in this regard. The purpose of this report is to document the development and acceptance testing of the eddy current system conducted to qualify its use for the measurement of aluminum hydroxide coating thicknesses on fuel stored in the K West Basin.

  11. Surface figure and roughness tolerances for NIF optics and the interpretation of the gradient, P-V wavefront and RMS specifications

    SciTech Connect (OSTI)

    Aikens, D M; English, R E; House, W; Lawson, J K; Nichols, M A; Whistler, W T

    1999-07-01T23:59:59.000Z

    In a high energy laser system such as the National Ignition Facility (NIF), the ability to focus light into as small a spot as possible at the highest possible fluence is highly dependent on the quality of the optics used in the system. Typically, surface form errors and transmitted and reflected wavefront errors are specified in terms of a peak-to-valley wavefront error (P-V), or occasionally in terms of an RMS wavefront error (RMS) 1 . It has been shown, however, that the parameter that most closely correlates with beam focusability is neither of these, but the RMS of the gradients of the wavefront error (RMS Gradient). Further, the spatial frequency of the wavefront error plays a significant role in the way that a given error effects the performance of the laser system, so careful attention must be paid to how the spatial filtering is both specified and accomplished. Since ISO 10110 has no specific provisions for a gradient specification, LLNL has developed its own notation and procedures for these critical specifications. In evaluating surface figure errors as specified by the NIF drawings, modern phase modulating interferometers (PMI) will be used. In addition to performing QA testing of the optics, LLNL intends to utilize the software capabilities of the instruments to obtain the information to model the wavefront of the 131 passes through various optical elements comprising the NIF front end. Tests will be performed and documented after coating and as installed in the specified mechanical mounts. This paper describes the evaluation of the wavefront error for NIF small optics including specifications over a given spatial period callout, the proper low pass filtering of the data and the allowable filtering and settings that can be applied to obtain proper wavefront data. This paper also describes the origin and evolution of other NIF wavefront and roughness specifications, and gives examples. Since the wavefront requirements and hence the specifications vary for the different systems in the NIF, we will focus on one system, the injection laser system (ILS) or ''front end''. Also discussed will be the metrology and data manipulation requirements for the large aperture optics. Finally, clarification will be given to the differences between various versions of the RMS wavefront and roughness specifications allowed in ISO 10110, and how they contrast to the RMS roughness specifications used in ANSI-Y14.5.

  12. 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

    2006-03-02T23:59:59.000Z

    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

  13. 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

    2015-06-12T23:59:59.000Z

    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.

  14. Lamellar thickness and stretching temperature dependency of cavitation in semicrystalline polymers

    E-Print Network [OSTI]

    Yaotao Wang; Zhiyong Jiang; Lianlian Fu; Ying Lu; Yongfeng Men

    2014-05-13T23:59:59.000Z

    Polybutene-1 (PB-1), a typical semicrystalline polymer, in its stable form I shows a peculiar temperature dependent strain-whitening behavior when being stretched at different temperatures where the extent of strain-whitening weakens with the increasing of stretching temperature reaching a minima value followed by an increase at higher stretching temperatures. Correspondingly, a stronger strain-hardening phenomenon was observed at higher stretching temperatures. The strain-whitening phenomenon in semicrystalline polymers has its origin of cavitation process during stretching. In this work, the effect of crystalline lamellar thickness and stretching temperature on the cavitation process in PB-1 has been investigated by means of combined synchrotron ultrasmall-angle and wide-angle X-ray scattering techniques. It was found that, with respect to the cavitation process, three modes of cavitation during the stretching process can be identified, namely no cavitation for sample with the thinnest lamellae where only shear yielding occurred, cavitation with reorientation for the samples stretched at lower temperatures and samples with thicker lamellae, and cavitation without reorientation for samples with thinner lamellae stretched at higher temperatures. The mode cavitation with reorientation occurs before yield point where the plate-like cavities start to be generated within the lamellar stacks with normal perpendicular to the stretching direction due to the blocky substructure of the crystalline lamellae and reorient gradually to the stretching direction after strain-hardening. The mode of cavitation without reorientation appears after yield point where ellipsoidal shaped cavities are generated in those lamellae stacks with normal parallel to the stretching direction followed by an improvement of their orientation at larger strains.

  15. 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]

    Steyerl, A; Müller, G; Golub, R

    2015-01-01T23:59:59.000Z

    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 arbitra...

  16. A study of the turbulent intensities and correlation coefficients in the incompressible flow of air in transition from a smooth to a rough wall in a two-dimensional channel

    E-Print Network [OSTI]

    Carper, Herbert Jackson

    1962-01-01T23:59:59.000Z

    A STUDY OF THE TURBULENT INTENSITIES AND CORRELATION COEFFICIENTS IN THE INCOMPRESSIBLE FLOW OF AIR IN TRANSITION FROM A SMOOTH TO A ROUGH WALL IN A TWO-DIMENSIONAL CHANNEL A Thesis By HERBERT JACKSON CARPER JR. Submitted to the Graduate... COEFFICIENTS IN THE INCOMPRESSIBLE FLOW OF AIR IN TRANSITION FROM A SMOOTH TO A ROUGH WALL IN A TWO-DIMENSIONAL CHANNEL A Thesis By HERBERT JACKSON CARPER JR. Approved as to style and content by: (Chairm of o e) (Head of Department) August 1962 853958...

  17. 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.

    2013-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Johnson, Jay R. [PPPL; Wing, Simon [Johns Hopkins University

    2014-08-01T23:59:59.000Z

    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.

  19. 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

  20. Assessment of MODIS cloud effective radius and optical thickness2 retrievals over the Southeast Pacific with VOCALS-Rex in-situ3

    E-Print Network [OSTI]

    Miami, University of

    in the Earth's radiation budget and the global climate.51 Cloud optical thickness (! ) and effective radius1 Assessment of MODIS cloud effective radius and optical thickness2 retrievals over, the standard 2.1 micron-derived MODIS32 effective radius (re) systematically exceeded the in-situ cloud

  1. 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)

    2011-11-15T23:59:59.000Z

    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).

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

    E-Print Network [OSTI]

    Wei, Gao-Feng

    2015-01-01T23:59:59.000Z

    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.

  3. 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)

    2014-02-17T23:59:59.000Z

    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.

  4. Measurement and effects of polarization fields on one-monolayer-thick InN/GaN multiple quantum wells

    SciTech Connect (OSTI)

    Zhou, Lin; Dimakis, E.; Hathwar, R.; Aoki, Toshihiro; Smith, David J.; Moustakas, T. D.; Goodnick, S. M.; McCartney, Martha R.

    2013-09-25T23:59:59.000Z

    Polarization fields associated with one-monolayer-thick InN/GaN multiple quantum wells (MQWs) cause shifts of the photoluminescence peak that depend on the GaN barrier layer thickness. Diffraction contrast and aberration-corrected scanning transmission electron microscopy show that the InN QWs are well defined and coherently strained. Mapping of electrostatic potential using off-axis electron holography shows that the electric fields inside the GaN barriers decrease from ?0.7 to ?0.2 MV/cm as the barrier layer thickness increases from 5 to 20 nm. Atomistic tight-binding calculations agree closely with experiment, and confirm that changes in optical emission of these III-nitride quantum wells result from changes in the spontaneous and piezoelectric polarization fields in the InN quantum wells and the GaN barrier layers. Overall, this QW system provides the basis for InN-based light-emitting devices operating across a useful band of wavelengths at room temperature.

  5. 3-D Deep Penetration Neutron Imaging of Thick Absorgin and Diffusive Objects Using Transport Theory

    SciTech Connect (OSTI)

    Ragusa, Jean; Bangerth, Wolfgang

    2011-08-01T23:59:59.000Z

    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

  6. 27th European Photovoltaic Solar Energy Conference, Frankfurt, Germany, 24-28 September 2012, 2AO.1.5 IMPACT OF THE REAR SURFACE ROUGHNESS ON INDUSTRIAL-TYPE PERC SOLAR CELLS

    E-Print Network [OSTI]

    -generation industrial solar cells as stated in the International Technology Roadmap [3]. An industrial PERC process flow27th European Photovoltaic Solar Energy Conference, Frankfurt, Germany, 24-28 September 2012, 2AO.1.5 IMPACT OF THE REAR SURFACE ROUGHNESS ON INDUSTRIAL-TYPE PERC SOLAR CELLS C.Kranz1 , S. Wyczanowski1 , S

  7. 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

  8. 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

    2015-05-13T23:59:59.000Z

    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.

  9. Temperature-dependent tensile strength, surface roughness diagnostics, and magnetic support and positioning of polymer ICF shells. Final report, October 1, 1993--April 30, 1995

    SciTech Connect (OSTI)

    Honig, A.

    1995-12-15T23:59:59.000Z

    During the course of this grant, we perfected emissivity and accommodation coefficient measurements on polymer ICF shells in the temperature range 250 to 350 K. Values for polystyrene shells are generally between 10{sup -2} and 10{sup -3}, which are very advantageous for ICF at cryogenic temperatures. Preliminary results on Br doped target shells indicate an accommodation coefficient, presumably associated with surface roughness on an atomic scale, about an order of magnitude larger than for ordinary polystyrene target shells. We also constructed apparatus with optical access for low temperature tensile strength and emissivity measurements, and made preliminary tests on this system. Magnetic shells were obtained both from GDP coating and from doping styrene with 10 manometer size ferromagnetic particles. The magnetic properties were measured through electron spin resonance (ESR). These experiments confirm the applicability of the Curie law, and establish the validity of using ESR measurements to determine shell temperature in the low temperature regime from 4K to 250K, thus complementing our presently accessible range. The high electron spin densities (> 10{sup 20}/CM{sup 3}) suggest magnetic levitation should be feasible at cryogenic temperatures. This work has resulted in two conference presentations, a Technical Report, a paper to be published in Fusion Technology, and a Master`s Thesis.

  10. Evaluation of thickness and strain of thin planar layers of InAs on GaAs(001) using spectroscopic ellipsometry

    SciTech Connect (OSTI)

    Eyink, K. G.; Szmulowicz, F.; Esposito, D.; Grazulis, L.; Hill, M.; Mahalingam, K.; Aronow, A. J. [Nano Electronic Materials Branch (RXAN), Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433-7707 (United States)

    2014-07-21T23:59:59.000Z

    We develop a technique for accurately measuring thickness of planar InAs films grown on (001) GaAs by spectroscopic ellipsometry, using bulk optical constants. We observe that the critical point structure for the E{sub 1} and E{sub 1}?+??{sub 1} transitions extracted from the measured dielectric properties varies with strain in the layer. Transmission electron microscopy confirms the extracted thickness and measures the residual strain based on the dislocation spacing in the film. At small thickness, the E{sub 1} critical point is seen to markedly deviate from the dependence predicted by deformation potential theory and appears to be consistent with additional quantum confinement effects.

  11. Thickness dependence of magnetic anisotropy in thin Ni films electrodeposited onto the (011) and (001) surfaces of n-GaAs

    SciTech Connect (OSTI)

    Gubbiotti, G.; Carlotti, G.; Tacchi, S.; Liu, Y.-K.; Scheck, C.; Schad, R.; Zangari, G. [INFM CRS-SOFT, c/o Universita di Roma 'La Sapienza', I-00185, Rome (Italy); INFM UdR-Perugia, c/o Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); INFM-National Center for nanoStructures and bioSystem at Surfaces (S3) Modena, and Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); IINFM UdR-Perugia, Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); MINT Center, University of Alabama, Tuscaloosa Alabama 35401 (United States); Department of Materials Science and Engineering and Center for Electrochemical Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2005-05-15T23:59:59.000Z

    Brillouin light scattering from thermal spin waves has been exploited to investigate the thickness dependence of magnetic anisotropy of Ni films, with thickness in the range 7-35 nm, grown by electrodeposition onto either (011)- or (001)-GaAs substrates. In the former case, Ni films exhibit a well-defined in-plane uniaxial anisotropy induced by the symmetry of the substrate. In the case of the (001)-GaAs substrate, instead, the magnetic anisotropy results from a combination of both a fourfold and a twofold contribution. The physical mechanisms responsible for the observed anisotropy, as well as its dependence on film thickness, are discussed in detail.

  12. Improvements in Low-Frequency, Ultrasonic Phased-Array Evaluation for Thick Section Cast Austenitic Stainless Steel Piping Components

    SciTech Connect (OSTI)

    Anderson, Michael T.; Crawford, Susan L.; Diaz, Aaron A.; Moran, Traci L.

    2010-12-01T23:59:59.000Z

    Research is being conducted for the U.S. Nuclear Regulatory Commission (NRC) at the Pacific Northwest National Laboratory (PNNL) to assess the effectiveness and reliability of advanced nondestructive examination (NDE) methods for the inspection of light water reactor (LWR) components. A primary objective of this work is to evaluate various NDE methods to assess their ability to detect, localize, and size cracks in coarse-grained steel components. This particular study focused on the evaluation of custom-designed, low-frequency (500 kHz) phased-array (PA) probes for examining welds in thick-section cast austenitic stainless steel (CASS) piping. In addition, research was conducted to observe ultrasonic sound field propagation effects from known coarse-grained microstructures found in parent CASS material. The study was conducted on a variety of thick-wall, coarse-grained CASS specimens that were previously inspected by an older generation 500-kHz PA-UT probe and acquisition instrument configuration. This comparative study describes the impact of the new PA probe design on flaw detection and sizing in a low signal-to-noise environment. The set of Pressurized Water Reactor Owners Group (PWROG) CASS specimens examined in this study are greater than 50.8-mm (2.0-in.) thick with documented flaws and microstructures. These specimens are on loan to PNNL from the Electric Power Research Institute (EPRI) NDE Center in Charlotte, North Carolina. The flaws contained within these specimens are thermal fatigue cracks (TFC) or mechanical fatigue cracks (MFC) and range from 13% to 42% in through-wall extent. In addition, ultrasonic signal continuity was evaluated on two CASS parent material ring sections by examining the edge-of-pipe response (corner geometry) for regions of signal loss.

  13. Characterization of AlGaN/GaN Heterostructure Field Effect Transistors (HFETs) with Variable Thickness Channel and Substrate Type

    SciTech Connect (OSTI)

    Hussein, A. SH.; Hassan, Z.; Hassan, H. Abu; Thahab, S. M. [Nano-Optoelectronics Research and Technology Laboratory, School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia)

    2010-07-07T23:59:59.000Z

    In this study, AlGaN/GaN-based heterostructure field effect transistor (HFET) was simulated by using ISE TCAD software. The effects of varying thickness, substrate type and doping channel levels were investigated. The device output characteristics of drain current and voltage with various gate biases were presented. A maximum drain current and extrinsic transconductance were achieved with AlGaN HFET grown on AlN/SiC substrate. The device performance can be improved by optimizing the substrate type and heavily doped channel layer which will reduce the contact resistance and enhance the transconductance. All results are comparable with the experimental results obtained by other researchers.

  14. Rough Paths Theory Fabrice Baudoin

    E-Print Network [OSTI]

    2013-04-09T23:59:59.000Z

    Let p > 2. If xn : [0,1] ? Rd is a sequence of bounded variation paths ... The fundamental theorem of Lyons is the following: ... Brownian motion (B(t))t?0.

  15. Fundamental Mechanisms of Interface Roughness

    SciTech Connect (OSTI)

    Randall L. Headrick

    2009-01-06T23:59:59.000Z

    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.

  16. Pavement roughness on expansive clays

    E-Print Network [OSTI]

    Velasco, Manuel O

    1980-01-01T23:59:59.000Z

    0 I/I Ql 0 Z 0 V- IU 0 Soil samples were taken adjacent to the roadway segments using a manual auger, in general at depths of 1, 2, and 3 feet. A total of 60 samples were brought to the laboratory, where the following tests have been...

  17. 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.

    1996-01-01T23:59:59.000Z

    materials. With respect to the latter, much of the research pertaining to wind effects has been done by structural engineers regarding wind hfting forces on building roof sections and forces on the face of buildings [Sachs, 1978, Melaragno, 1982]. Very... the flow is in a smooth linear path or in stratified laminae or layers. Turbulence occurs when there is random erratic movement breaking the smoothness of the flow [Melaragno, 1982]. At a point back from the leading edge of a plate, the laminar boundary...

  18. EXERCISE-INDUCED ACUTE CHANGES IN SYSTOLIC BLOOD PRESSURE DO NOT ALTER CHOROIDAL THICKNESS AS MEASURED BY A PORTABLE SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY DEVICE

    E-Print Network [OSTI]

    Alwassia, Ahmad A.

    Purpose: To measure choroidal thickness in patients manifesting an acute change in systemic arterial blood pressure using a portable spectral-domain optical coherence tomography device (iVue).

  19. Impact of barrier thickness on transistor performance in AlN/GaN high electron mobility transistors grown on free-standing GaN substrates

    SciTech Connect (OSTI)

    Deen, David A., E-mail: david.deen@alumni.nd.edu; Storm, David F.; Meyer, David J.; Bass, Robert; Binari, Steven C. [Electronics Science and Technology Division, Naval Research Laboratory, Washington, DC 20375-5347 (United States); Gougousi, Theodosia [Physics Department, University of Maryland Baltimore County, Baltimore, Maryland 21250 (United States); Evans, Keith R. [Kyma Technologies, Raleigh, North Carolina 27617 (United States)

    2014-09-01T23:59:59.000Z

    A series of six ultrathin AlN/GaN heterostructures with varied AlN thicknesses from 1.5–6?nm have been grown by molecular beam epitaxy on free-standing hydride vapor phase epitaxy GaN substrates. High electron mobility transistors (HEMTs) were fabricated from the set in order to assess the impact of barrier thickness and homo-epitaxial growth on transistor performance. Room temperature Hall characteristics revealed mobility of 1700?cm{sup 2}/V s and sheet resistance of 130 ?/? for a 3?nm thick barrier, ranking amongst the lowest room-temperature sheet resistance values reported for a polarization-doped single heterostructure in the III-Nitride family. DC and small signal HEMT electrical characteristics from submicron gate length HEMTs further elucidated the effect of the AlN barrier thickness on device performance.

  20. High-energy threshold reaction rates on 0.8 GeV proton-irradiated thick Pb-target

    E-Print Network [OSTI]

    Yu. E. Titarenko; V. F. Batyaev; A. Yu. Titarenko; M. A. Butko; K. V. Pavlov; R. S. Tikhonov; S. N. Florya; S. G. Mashnik; W. Gudowski

    2007-05-08T23:59:59.000Z

    This works presents results of activation-aided determination of threshold reaction rates in 92 209Bi, natPb, 197Au, 181Ta, 169Tm, natIn, 93Nb, 64Zn, 65Cu, 63Cu, 59Co, 19F, and 12C samples and in 121 27Al samples. All the samples were aligned with the proton beam axis inside and outside the demountable 92-cm thick Pb target of 15-cm diameter assembled of 23 4-cm thick discs. The samples were placed on 12 target disks to reproduce the long axis distribution of protons and neutrons. In June 2006, the target was exposed for 18 hours to a 800-MeV proton beam extracted from the ITEP U-10 accelerator. The proton fluence and the proton beam shape were determined using the 27Al(p,x)7Be monitor reaction. The reaction rates were determined by the direct gamma-spectrometry techniques. In total, 1196 gamma-spectra have been measured, and about 1500 reaction rates determined. The measured reaction rates were simulated by the MCNPX code using the following databases: ENDF/B6 for neutrons below 20 MeV, MENDL2 for 20-100 MeV neutrons, and MENDL2P for proton cross sections up to 200 MeV. An acceptable agreement of simulations with experimental data has been found.

  1. 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

    2007-02-12T23:59:59.000Z

    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.

  2. Viscoelastic fluid flow in a 2D channel bounded above by a deformable finite thickness elastic wall

    E-Print Network [OSTI]

    Chakraborty, Debadi

    2015-01-01T23:59:59.000Z

    The steady flow of three viscoelastic fluids (Oldroyd-B, FENE-P, and Owens model for blood) in a two-dimensional channel, partly bound by a deformable, finite thickness neo-Hookean solid, is computed. The limiting Weissenberg number beyond which computations fail to converge is found to increase with increasing dimensionless solid elasticity parameter {\\Gamma}, following the trend Owens > FENE- P > Oldroyd-B. The highly shear thinning nature of Owens model leads to the elastic solid always collapsing into the channel, for the wide range of values of {\\Gamma} considered here. In the case of the FENE-P and Oldroyd-B models, however, the fluid-solid interface can be either within the channel, or bulge outwards, depending on the value of {\\Gamma}. This behaviour differs considerably from predictions of earlier models that treat the deformable solid as a zero-thickness membrane, in which case the membrane always lies within the channel. The capacity of the solid wall to support both pressure and shear stress, in c...

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

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.); Ho, Cheng,

    2002-01-01T23:59:59.000Z

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

  4. Liquid crystal films as on-demand, variable thickness (50–5000?nm) targets for intense lasers

    SciTech Connect (OSTI)

    Poole, P. L., E-mail: poole.134@osu.edu; Andereck, C. D.; Schumacher, D. W.; Daskalova, R. L.; Feister, S.; George, K. M.; Willis, C.; Akli, K. U.; Chowdhury, E. A. [Physics Department, The Ohio State University, Columbus, Ohio 43210 (United States)

    2014-06-15T23:59:59.000Z

    We have developed a new type of target for intense laser-matter experiments that offers significant advantages over those currently in use. The targets consist of a liquid crystal film freely suspended within a metal frame. They can be formed rapidly on-demand with thicknesses ranging from nanometers to micrometers, where the particular value is determined by the liquid crystal temperature and initial volume as well as by the frame geometry. The liquid crystal used for this work, 8CB (4?-octyl-4-cyanobiphenyl), has a vapor pressure below 10{sup ?6}?Torr, so films made at atmospheric pressure maintain their initial thickness after pumping to high vacuum. Additionally, the volume per film is such that each target costs significantly less than one cent to produce. The mechanism of film formation and relevant physics of liquid crystals are described, as well as ion acceleration data from the first shots on liquid crystal film targets at the Ohio State University Scarlet laser facility.

  5. The frequency of tropopause-level thick and thin cirrus clouds as observed by CALIPSO and the relationship to relative humidity and outgoing longwave radiation

    E-Print Network [OSTI]

    Cardona, Allison Leanne

    2008-10-10T23:59:59.000Z

    THE FREQUENCY OF TROPOPAUSE-LEVEL THICK AND THIN CIRRUS CLOUDS AS OBSERVED BY CALIPSO AND THE RELATIONSHIP TO RELATIVE HUMIDITY AND OUTGOING LONGWAVE RADIATION A Thesis by ALLISON L. CARDONA Submitted to the Office of Graduate... Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 2008 Major Subject: Atmospheric Sciences THE FREQUENCY OF TROPOPAUSE-LEVEL THICK AND THIN CIRRUS CLOUDS AS OBSERVED...

  6. Effects of Co layer thickness and annealing temperature on the magnetic properties of inverted [Pt/Co] multilayers

    SciTech Connect (OSTI)

    Lee, Tae Young; Chan Won, Young [Department of Nano Semiconductor Engineering, Korea University, Seoul 136-713 (Korea, Republic of); Su Son, Dong; Lee, Seong-Rae [Department of Materials Science and Engineering, Korea University, Seoul 136-713 (Korea, Republic of); Ho Lim, Sang, E-mail: sangholim@korea.ac.kr [Department of Nano Semiconductor Engineering, Korea University, Seoul 136-713 (Korea, Republic of); Department of Materials Science and Engineering, Korea University, Seoul 136-713 (Korea, Republic of)

    2013-11-07T23:59:59.000Z

    The effects of Co layer thickness and annealing temperature on the perpendicular magnetic anisotropy (PMA) properties of inverted [Pt (0.2?nm)/Co (t{sub Co})]{sub 6} multilayers (where t{sub Co} indicates the thickness of the Co layer) have been investigated. The cross-sectional microstructure, as observed from the high-resolution transmission electron microscope images, shows a clear layered structure with atomically flat interfaces both in the as-deposited state as well as after annealing, indicating the interface effects for PMA. The effective PMA energy density (K{sub eff}) increases significantly with an increase in t{sub Co} from 0.2 to 0.28?nm and then becomes almost saturated with further increases in t{sub Co}, followed by a slight reduction at the highest Co thickness, t{sub Co}?=?0.6?nm. In order to explain the t{sub Co} dependence on K{sub eff}, the intrinsic PMA energy density (K{sub i}) is calculated by additionally measuring a similar set of results for the saturation magnetization. The K{sub i} value increases nearly linearly with the increase in t{sub Co} from 0.2 to 0.5?nm, followed by saturation at a higher t{sub Co} value of 0.6?nm. Owing to a close relationship between K{sub i} and the quality of the interfaces, these results indicate a similar t{sub Co} dependence on the quality of the interfaces. This is further supported from the magnetic measurements of the samples annealed at the highest temperature of 500?°C, where a second phase is formed, which show a similar t{sub Co} dependence on the amount of the second phase. The K{sub i} value is nearly independent of the annealing temperature at t{sub Co}???0.4?nm, above which a substantial reduction is observed, when the annealing temperature exceeds 500?°C.

  7. The effect of Ta on the magnetic thickness of permalloy (Ni{sub 81}Fe{sub 19}) films

    SciTech Connect (OSTI)

    Kowalewski, M. [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Butler, W. H. [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Moghadam, N. [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Stocks, G. M. [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Schulthess, T. C. [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Song, K. J. [Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Thompson, J. R. [Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Arrott, A. S. [Honeywell, Inc., MN14-3C15, 12001 State Highway 55, Plymouth, Minnesota 55441 (United States)] [Honeywell, Inc., MN14-3C15, 12001 State Highway 55, Plymouth, Minnesota 55441 (United States); Zhu, T. [Honeywell, Inc., MN14-3C15, 12001 State Highway 55, Plymouth, Minnesota 55441 (United States)] [Honeywell, Inc., MN14-3C15, 12001 State Highway 55, Plymouth, Minnesota 55441 (United States); Drewes, J. [Honeywell, Inc., MN14-3C15, 12001 State Highway 55, Plymouth, Minnesota 55441 (United States)] (and others) [Honeywell, Inc., MN14-3C15, 12001 State Highway 55, Plymouth, Minnesota 55441 (United States)

    2000-05-01T23:59:59.000Z

    The effect of Ta and Ta/Cu seed layers, and Ta and Cu cap layers on the effective magnetic thickness of ultrathin permalloy (Ni{sub 81}Fe{sub 19}) was investigated for MRAM applications. The films were deposited by Ion Beam Deposition. The magnetic moment of each as-deposited permalloy film was measured using a B-H looper and a SQUID magnetometer. The films were further annealed at either 525 K for 1/2 h or 600 K for 1 h to study the effect of thermally driven interdiffusion on the magnetic moment of the permalloy film. Our theoretical calculations showed that the presence of 12% intermixing at the interface reduces the Ni moments to zero. Experimentally, it was shown that the tantalum rather than the copper interfaces are primarily responsible for the magnetically dead layers. The Ta seed layer interface produces a loss of moment equivalent to a magnetically dead layer of thickness 0.6{+-}0.2 nm. The Ta metal in the cap layer results in a loss of moment equivalent to a dead layer of thickness 1.0{+-}0.2 nm. Upon annealing, thermally driven interdiffusion is concluded to have a strong effect on the Ta(seed)/ Ni{sub 81}Fe{sub 19} as-deposited interface, based on the doubling of the magnetically dead layer to 1.2{+-}0.2 nm. The Ni{sub 81}Fe{sub 19}/Ta(cap) as-deposited interface slightly increases its equivalent magnetically dead layer upon annealing to 1.2{+-}0.2 nm. As-deposited interfaces of Ta(seed)/permalloy and permalloy/Ta(cap) are not chemically equivalent and result in different magnetically dead layers, whereas after annealing to 600 K both interfaces attain comparable intermixing and magnetically dead layers. It was also shown that a half-hour anneal at the lower 525 K annealing temperature, which is closer to the actual processing temperature, results in only slight increase of the magnetically dead layer at both interfaces. (c) 2000 American Institute of Physics.

  8. 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)

    2014-04-07T23:59:59.000Z

    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.

  9. Theoretical comparison of multiple quantum wells and thick-layer designs in InGaN/GaN solar cells

    SciTech Connect (OSTI)

    Cavassilas, Nicolas; Michelini, Fabienne; Bescond, Marc [Aix Marseille Univ, CNRS, IM2NP UMR 7334, 13384 Marseille (France)

    2014-08-11T23:59:59.000Z

    This theoretical work analyzes the photovoltaic effect in non-polar InGaN/GaN solar cells. Our electronic transport model considers quantum behaviors related to confinement, tunneling, electron-phonon, and electron-photon scatterings. Based on this model, we compare a multiple quantum wells cell with its thick-layer counterpart. We show that the structure of multiple quantum wells is a promising design providing better compromise between photon-absorption and electronic transport. This balance is necessary since these two phenomena are shown to be antagonist in nanostructure based solar cells. In these devices, we also show that phonon absorption increases the short-circuit current, while phonon emission reduces the open-circuit voltage.

  10. 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.

    2011-08-12T23:59:59.000Z

    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.

  11. 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

    2013-10-02T23:59:59.000Z

    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.

  12. Formation of solar cells based on Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} (BST) ferroelectric thick film

    SciTech Connect (OSTI)

    Irzaman,, E-mail: irzaman@yahoo.com; Syafutra, H., E-mail: irzaman@yahoo.com; Arif, A., E-mail: irzaman@yahoo.com; Alatas, H., E-mail: irzaman@yahoo.com [Department of Physics, FMIPA Bogor Agricultural Unversity, Campus Darmaga Gedung Wing S Bogor (Indonesia); Hilaluddin, M. N.; Kurniawan, A.; Iskandar, J.; Dahrul, M.; Ismangil, A.; Yosman, D.; Aminullah [Department of Biophysics, FMIPA Bogor Agricultural Unversity (Indonesia); Prasetyo, L. B. [Department of Forest Resources Conservation, FAHUTAN, Bogor Agricultural Unversity, Campus Darmaga Bogor (Indonesia); Yusuf, A.; Kadri, T. M. [LAPAN Rancabungur Ciampea Bogor (Indonesia)

    2014-02-24T23:59:59.000Z

    Growth of Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} (BST) 1 M thick films are conducted with variation of annealing hold time of 8 hours, 15 hours, 22 hours, and 29 hours at a constant temperature of 850 °C on p-type Si (100) substrate using sol-gel method then followed by spin coating process at 3000 rpm for 30 seconds. The BST thick film electrical conductivity is obtained to be 10{sup ?5} to 10{sup ?4} S/cm indicate that the BST thick film is classified as semiconductor material. The semiconductor energy band gap value of BST thick film based on annealing hold time of 8 hours, 15 hours, 22 hours, and 29 hours are 2.58 eV, 3.15 eV, 3.2 eV and 2.62 eV, respectively. The I-V photovoltaic characterization shows that the BST thick film is potentially solar cell device, and in accordance to annealing hold time of 8 hours, 15 hours, 22 hours and 29 hours have respective solar cell energy conversion efficiencies of 0.343%, 0.399%, 0.469% and 0.374%, respectively. Optical spectroscopy shows that BST thick film solar cells with annealing hold time of 8 hours, 15 hours, and 22 hours absorb effectively light energy at wavelength of ? 700 nm. BST film samples with annealing hold time of 29 hours absorb effectively light energy at wavelength of ? 700 nm. The BST thick film refraction index is between 1.1 to 1.8 at light wavelength between ±370 to 870 nm.

  13. Critical shell thickness for InAs-Al{sub x}In{sub 1-x}As(P) core-shell nanowires

    SciTech Connect (OSTI)

    Haapamaki, C. M.; LaPierre, R. R. [Department of Engineering Physics, Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4L7 (Canada); Baugh, J. [Institute for Quantum Computing and Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2012-12-15T23:59:59.000Z

    InAs nanowires with Al{sub x}In{sub 1-x}P or Al{sub x}In{sub 1-x}As shells were grown on GaAs substrates by the Au-assisted vapour-liquid-solid method in a gas source molecular beam epitaxy system. Core diameters and shell thicknesses were measured by transmission electron microscopy (TEM). These measurements were then related to selected area diffraction patterns to verify either interface coherency or relaxation through misfit dislocations. A theoretical strain model is presented to determine the critical shell thickness for given core diameters. Zincblende stiffness parameters are transformed to their wurtzite counterparts via a well known tensor transformation. An energy criterion is then given to determine the shell thickness, at which coherency is lost and dislocations become favourable. Our model only considers axial strain relieved by edge dislocations since they were the only type of dislocation observed directly by TEM.

  14. Thick Buildings [Standards

    E-Print Network [OSTI]

    Coffin, Christie Johnson

    1995-01-01T23:59:59.000Z

    on Occupant Behavior in Buildings, New Directions forSacramento, is a thin building that surrounds an atrium. (Performance of a Green Building," Urban UndQune 1992): 23-

  15. HIGH-RESOLUTION IMAGING OF SOLAR FLARE RIBBONS AND ITS IMPLICATION ON THE THICK-TARGET BEAM MODEL

    SciTech Connect (OSTI)

    Krucker, Saem; Hudson, H. S.; Lin, R. P. [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States); Jeffrey, N. L. S.; Battaglia, M.; Kontar, E. P. [Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Benz, A. O.; Csillaghy, A., E-mail: krucker@ssl.berkeley.edu [Institute of 4D Technologies, School of Engineering, University of Applied Sciences Northwestern Switzerland, 5210 Windisch (Switzerland)

    2011-10-01T23:59:59.000Z

    We report on high-resolution optical and hard X-ray observations of solar flare ribbons seen during the GOES X6.5 class white-light flare of 2006 December 6. The data consist of imaging observations at 430 nm (the Fraunhofer G band) taken by the Hinode Solar Optical Telescope with the hard X-rays observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager. The two sets of data show closely similar ribbon structures, strongly suggesting that the flare emissions in white light and in hard X-rays have physically linked emission mechanisms. While the source structure along the ribbons is resolved at both wavelengths (length {approx} 30''), only the G-band observations resolve the width of the ribbon, with values between {approx}0.''5 and {approx}1.''8. The unresolved hard X-ray observations reveal an even narrower ribbon in hard X-rays (the main footpoint has a width perpendicular to the ribbon of <1.''1 compared to the G-band width of {approx}1.''8) suggesting that the hard X-ray emission comes from the sharp leading edge of the G-band ribbon. Applying the thick-target beam model, the derived energy deposition rate is >5 x 10{sup 12} erg s{sup -1} cm{sup -2} provided by an electron flux of 1 x 10{sup 20} electrons s{sup -1} cm{sup -2} above 18 keV. This requires that the beam density of electrons above 18 keV be at least 1 x 10{sup 10} cm{sup -3}. Even if field lines converge toward the chromospheric footpoints, the required beam in the corona has too high a density to be described as a dilute tail population on top of a Maxwellian core. We discuss this issue and others associated with this extreme event, which poses serious questions to the standard thick target beam interpretation of solar flares.

  16. 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)

    2014-02-18T23:59:59.000Z

    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.

  17. ALMA 690 GHz OBSERVATIONS OF IRAS 16293-2422B: INFALL IN A HIGHLY OPTICALLY THICK DISK

    SciTech Connect (OSTI)

    Zapata, Luis A.; Loinard, Laurent; Rodriguez, Luis F.; Hernandez-Hernandez, Vicente [Centro de Radioastronomia y Astrofisica, UNAM, Apdo. Postal 3-72 (Xangari), 58089 Morelia, Michoacan (Mexico); Takahashi, Satoko; Trejo, Alfonso [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China); Parise, Berengere [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany)

    2013-02-10T23:59:59.000Z

    We present sensitive, high angular resolution ({approx}0.''2) submillimeter continuum and line observations of IRAS 16293-2422B made with the Atacama Large Millimeter/Submillimeter Array. The 0.45 mm continuum observations reveal a single and very compact source associated with IRAS 16293-2422B. This submillimeter source has a deconvolved angular size of about 400 mas (50 AU) and does not show any inner structure inside of this diameter. The H{sup 13}CN, HC{sup 15}N, and CH{sub 3}OH line emission regions are about twice as large as the continuum emission and reveal a pronounced inner depression or ''hole'' with a size comparable to that estimated for the submillimeter continuum. We suggest that the presence of this inner depression and the fact that we do not see an inner structure (or a flat structure) in the continuum are produced by very optically thick dust located in the innermost parts of IRAS 16293-2422B. All three lines also show pronounced inverse P-Cygni profiles with infall and dispersion velocities larger than those recently reported from observations at lower frequencies, suggesting that we are detecting faster and more turbulent gas located closer to the central object. Finally, we report a small east-west velocity gradient in IRAS 16293-2422B that suggests that its disk plane is likely located very close to the plane of the sky.

  18. Thermal degradation of bacterial poly(hydroxybutyric acid): Mechanisms from the dependence of pyrolysis yields on sample thickness

    SciTech Connect (OSTI)

    Lehrle, R.S.; Williams, R.J. (Univ. of Birmingham (United Kingdom). School of Chemistry)

    1994-07-04T23:59:59.000Z

    The thermal degradation behavior at 350 C of poly(hydroxybutyric acid), Biopol'', has been studied by pyrolysis-GC using a microthermocouple-controlled filament. The overall pyrolysis mechanism--an array of parallel and consecutive processes--has been elucidated by a novel method. This involves the measurement of product yields as a function of sample thickness, for samples in the microgram range, pyrolyzed for a chosen duration (5 s was used in the present study). This approach provides indirect control of the residence time of primary products in the melt and thereby facilitates the detection of secondary reactions. From quantitative measurements of bonus yields and deficit yields, it is shown, for example, that only trans isomers are formed as primary products; trans-cis isomerizations then occur as secondary reactions. Moreover, although monomeric, dimeric, and trimeric products are formed by primary processes, there is evidence that a trimeric product is also formed by a consecutive reaction mechanism. Somewhat unexpectedly, the tetrameric products are formed exclusively by secondary reactions. This observation casts some doubt on the view that the pyrolysis products from this polymer can be accounted for entirely in terms of random ([beta]-elimination) scissions.

  19. Predicting the steady state thickness of passive films with the Point Defect Model in fretting corrosion experiments

    E-Print Network [OSTI]

    Geringer, Jean; Taylor, Mathew L

    2013-01-01T23:59:59.000Z

    Some implants have approximately a lifetime of 15 years. The femoral stem, for example, should be made of 316L/316LN stainless steel. Fretting corrosion, friction under small displacements, should occur during human gait, due to repeated loadings and un-loadings, between stainless steel and bone for instance. Some experimental investigations of fretting corrosion have been practiced. As well known, metallic alloys and especially stainless steels are covered with a passive film that prevents from the corrosion and degradation. This passive layer of few nanometers, at ambient temperature, is the key of our civilization according to some authors. This work is dedicated to predict the passive layer thicknesses of stainless steel under fretting corrosion with a specific emphasis on the role of proteins. The model is based on the Point Defect Model (micro scale) and an update of the model on the friction process (micro-macro scale). Genetic algorithm was used for finding solution of the problem. The major results a...

  20. 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.

    2010-01-01T23:59:59.000Z

    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...

  1. formation of the main deposit. At lower current densities, it is possible to deposit only this extremely thin tin film: it is 5 nm thick

    E-Print Network [OSTI]

    Stocker, Thomas

    . Whereas the 200-nm copper and 300-nm tin films in Fig. 4 have a thickness close to that predicted. We propose the following mechan- istic explanation of this effect. First, in thin cells problems of Li rechargeable batteries. Indeed, cycling efficiency of Li batteries is drastically reduced

  2. 3. A. A. Sadovoi and N. M. Chulkov, "Distribution of kinetic energy dissipation into thermal energy over a spherical shell thickness because of viscosity," in: Calculation Algorithms

    E-Print Network [OSTI]

    Alexandrov, Victor

    3. A. A. Sadovoi and N. M. Chulkov, "Distribution of kinetic energy dissipation into thermal energy over a spherical shell thickness because of viscosity," in: Calculation Algorithms of Engineering and N. M. Chulkov, "Inertial convergence of cylindrical and spherical shells of incompressible

  3. Dose uncertainty due to computed tomography ,,CT... slice thickness in CT-based high dose rate brachytherapy of the prostate cancer

    E-Print Network [OSTI]

    Pouliot, Jean

    Dose uncertainty due to computed tomography ,,CT... slice thickness in CT-based high dose rate in Medicine. DOI: 10.1118/1.1785454 Key words: high dose rate brachytherapy, computed tomography, prostate at risk OARs by providing three-dimensional 3D anatomical information from computed tomography CT

  4. Heat Transfer -2 A heat generating ( ) flat plate fuel element of thickness 2L is covered with flat plate steel cladding of

    E-Print Network [OSTI]

    Virginia Tech

    with flat plate steel cladding of thickness b. The heat generated is removed by a fluid at T, which adjoins on both sides On the sketch show regions where dT/dx is zero, constant and increasing. T , h x LL bb SteelSteel

  5. The significant effect of the thickness of Ni film on the performance of the Ni/Au Ohmic contact to p-GaN

    SciTech Connect (OSTI)

    Li, X. J.; Zhao, D. G., E-mail: dgzhao@red.semi.ac.cn; Jiang, D. S.; Liu, Z. S.; Chen, P.; Zhu, J. J.; Le, L. C.; Yang, J.; He, X. G. [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Science, P.O. Box 912, Beijing 100083 (China); Zhang, S. M.; Zhang, B. S.; Liu, J. P. [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Yang, H. [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Science, P.O. Box 912, Beijing 100083 (China); Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123 (China)

    2014-10-28T23:59:59.000Z

    The significant effect of the thickness of Ni film on the performance of the Ohmic contact of Ni/Au to p-GaN is studied. The Ni/Au metal films with thickness of 15/50?nm on p-GaN led to better electrical characteristics, showing a lower specific contact resistivity after annealing in the presence of oxygen. Both the formation of a NiO layer and the evolution of metal structure on the sample surface and at the interface with p-GaN were checked by transmission electron microscopy and energy-dispersive x-ray spectroscopy. The experimental results indicate that a too thin Ni film cannot form enough NiO to decrease the barrier height and get Ohmic contact to p-GaN, while a too thick Ni film will transform into too thick NiO cover on the sample surface and thus will also deteriorate the electrical conductivity of sample.

  6. Former presence of thick post-Devonian strata in northern Appalachian basin: Evidence from fluid-inclusion studies

    SciTech Connect (OSTI)

    Sarwar, G.; Friedman, G.M. (Brooklyn College of the City Univ. of New York, NY (USA))

    1989-08-01T23:59:59.000Z

    Along an 80-km long belt south of Syracuse, New York, the maximum fluid-inclusion homogenization temperatures (T{sub max}) of late-stage cements of the lower Middle Devonian Onondaga Limestone show a local high of 150{degree}-160{degree}C in central New York. T{sub max} decreases both west and east of this area reaching about 100{degree}C in outcrops near Buffalo and Albany, respectively. Southward from Albany, along the western margin of the Hudson Valley, T{sub max} again rises sharply to 170{degree}-180{degree}C in the Kingston area. The thermal alteration index (TAI) and vitrinite reflectance of the overlying Marcellus-Bakoven (Middle Devonian) black shales in central and eastern New York show a comparable trend. The east-west profile of T{sub max} of the Onondaga rocks as well as thermal maturity of the black shales show excellent correlation with similar profiles of authigenic magnetite in the Onondaga Limestone and of clay diagenesis and fission-track ages of the Middle Devonian Tioga Metabentonite Bed, as reported by others. The T{sub max} of the Onondaga Limestone is believed to have been attained during maximum burial, the extent of which can not be accounted for by the present thickness of post-Onondaga strata. As a result of an inferred late Paleozoic uplift, in western and eastern New York, 2-3 km of post-Devonian strata were removed, in central New York 4-5 km, and in southeastern New York 5-6 km were removed. The north-south variation in maximum burial along the Hudson Valley may be explained by additional impact of tectonic loading in the south.

  7. Magnetic properties and microstructure of Sm-Co/?-Fe nanocomposite thick film-magnets composed of multi-layers over 700 layers

    SciTech Connect (OSTI)

    Tou, A., E-mail: bb52112226@cc.nagasaki-u.ac.jp; Morimura, T.; Nakano, M.; Yamai, T.; Fukunaga, H. [Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521 (Japan)

    2014-05-07T23:59:59.000Z

    We synthesized Sm-Co/?-Fe nanocomposite film-magnets, approximately 10??m in thickness, composed of 780 layers by the pulse laser deposition method. Transmission electron microscopic observations revealed that the synthesized film is composed of Sm-Co and ?-Fe layers with the well-controlled ?-Fe thickness of approximately 10–20?nm, which is suitable one predicted by the micromagnetic simulation. In spite of the enhanced interlayer diffusion of Fe and Co by annealing for crystallization, the (BH){sub max} value of 100?kJ/m{sup 3} was obtained at the averaged compositions of Sm/(Sm?+?Co)?=?0.16 and Fe/(Sm?+?Co?+?Fe)?=?0.47. The ?-Fe fraction for obtaining the highest (BH){sub max} value was smaller than that expected from the micromagnetic simulation. Although the annealing for crystallization lay the easy direction of magnetization in the plane, the film is not expected to have strong crystallographic texture.

  8. 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

    2015-01-01T23:59:59.000Z

    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.

  9. 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

    2015-04-28T23:59:59.000Z

    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.

  10. buffer Layer Growth, the Thickness Dependence of Jc in Coated Conductors, Local Identification of Current Limiting Mechanisms and Participation in the Wire Development Group

    SciTech Connect (OSTI)

    Larbalestier, David; Hellstron, Eric; Abraimov, Dmytro

    2011-12-17T23:59:59.000Z

    The primary thrusts of our work were to provide critical understanding of how best to enhance the current-carrying capacity of coated conductors. These include the deconstruction of Jc as a function of fim thickness, the growth of in situ films incorporating strong pinning centers and the use of a suite of position-sensitive tools that enable location and analysis of key areas where current-limiting occurs.

  11. Expression of proliferative and inflammatory markers in a full-thickness human skin equivalent following exposure to the model sulfur mustard vesicant, 2-chloroethyl ethyl sulfide

    SciTech Connect (OSTI)

    Black, Adrienne T. [Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Hayden, Patrick J. [MatTek Corporation, Ashland, MA (United States); Casillas, Robert P. [Battelle Memorial Institute, Columbus, OH (United States); Heck, Diane E. [Environmental Health Sciences, New York Medical College, Valhalla, NY (United States); Gerecke, Donald R. [Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Sinko, Patrick J. [Pharmaceutics, Rutgers University, Piscataway, NJ (United States); Laskin, Debra L. [Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.ed [Environmental and Occupational Medicine, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ (United States)

    2010-12-01T23:59:59.000Z

    Sulfur mustard is a potent vesicant that induces inflammation, edema and blistering following dermal exposure. To assess molecular mechanisms mediating these responses, we analyzed the effects of the model sulfur mustard vesicant, 2-chloroethyl ethyl sulfide, on EpiDerm-FT{sup TM}, a commercially available full-thickness human skin equivalent. CEES (100-1000 {mu}M) caused a concentration-dependent increase in pyknotic nuclei and vacuolization in basal keratinocytes; at high concentrations (300-1000 {mu}M), CEES also disrupted keratin filament architecture in the stratum corneum. This was associated with time-dependent increases in expression of proliferating cell nuclear antigen, a marker of cell proliferation, and poly(ADP-ribose) polymerase (PARP) and phosphorylated histone H2AX, markers of DNA damage. Concentration- and time-dependent increases in mRNA and protein expression of eicosanoid biosynthetic enzymes including COX-2, 5-lipoxygenase, microsomal PGE{sub 2} synthases, leukotriene (LT) A{sub 4} hydrolase and LTC{sub 4} synthase were observed in CEES-treated skin equivalents, as well as in antioxidant enzymes, glutathione S-transferases A1-2 (GSTA1-2), GSTA3 and GSTA4. These data demonstrate that CEES induces rapid cellular damage, cytotoxicity and inflammation in full-thickness skin equivalents. These effects are similar to human responses to vesicants in vivo and suggest that the full thickness skin equivalent is a useful in vitro model to characterize the biological effects of mustards and to develop potential therapeutics.

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

    SciTech Connect (OSTI)

    Zaghloul, Usama, E-mail: uzheiba@andrew.cmu.edu [Electrical and Computer Engineering Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Microelectronics Department, Electronics Research Institute, 33 El Bohouth St., Dokki, Giza (Egypt); Piazza, Gianluca [Electrical and Computer Engineering Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States)

    2014-06-23T23:59:59.000Z

    The scaling of piezoelectric nanoelectromechanical systems (NEMS) is challenged by the synthesis of ultrathin and high quality piezoelectric films on very thin electrodes. We report the synthesis and characterization of the thinnest piezoelectric aluminum nitride (AlN) films (10?nm) ever deposited on ultrathin platinum layers (2–5?nm) using reactive sputtering. X-ray diffraction, high-resolution transmission electron microscopy, and fast Fourier transform analyses confirmed the proper crystal orientation, fine columnar texture, and the continuous lattice structure within individual grains in the deposited AlN nanometer thick films. The average extracted d{sub 31} piezoelectric coefficient for the synthesized films is ?1.73 pC/N, which is comparable to the reported values for micron thick and highly c-axis oriented AlN films. The 10?nm AlN films were employed to demonstrate two different types of optimized piezoelectric nanoactuators. The unimorph actuators exhibit vertical displacements as large as 1.1??m at 0.7?V for 25??m long and 30?nm thick beams. These results have a great potential to realize miniaturized NEMS relays with extremely low voltage, high frequency resonators, and ultrasensitive sensors.

  13. 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)

    2014-05-07T23:59:59.000Z

    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.

  14. 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.

    2011-07-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2006-06-01T23:59:59.000Z

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

  16. 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

    2006-04-28T23:59:59.000Z

    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.

  17. Development of a Versatile Laser-Ultrasonic System and Application to the Online Measurement for Process Control of Wall Thickness and Eccentricity of Seamless Tubes

    SciTech Connect (OSTI)

    Robert V. Kolarik II

    2002-10-23T23:59:59.000Z

    A system for the online, non-contact measurement of wall thickness in steel seamless mechanical tubing has been developed and demonstrated at a tubing production line at the Timken Company in Canton, Ohio. The system utilizes laser-generation of ultrasound and laser-detection of time of flight with interferometry, laser-doppler velocimetry and pyrometry, all with fiber coupling. Accuracy (<1% error) and precision (1.5%) are at targeted levels. Cost and energy savings have exceeded estimates. The system has shown good reliability in measuring over 200,000 tubes in its first six months of deployment.

  18. Measurements of delayed neutrons yields and time spectra from 1 GeV protons interacting with thick {sup nat}Pb targets

    SciTech Connect (OSTI)

    Ridikas, D. [CEA Saclay, DSM/DAPNIA, 91191 Gif-sur-Yvette (France); Barzakh, A. [Petersburg Nuclear Physics Inst., Leningrad district, 188350 Gatchina (Russian Federation); Blideanu, V.; David, J. C.; Dore, D. [CEA Saclay, DSM/DAPNIA, 91191 Gif-sur-Yvette (France); Fedorov, D. [Petersburg Nuclear Physics Inst., Leningrad district, 188350 Gatchina (Russian Federation); Ledoux, X. [CEA Bruyeres, DIF/DPTA, 91680 Bruyeres-le-Chatel (France); Moroz, F.; Panteleev, V. [Petersburg Nuclear Physics Inst., Leningrad district, 188350 Gatchina (Russian Federation); Plukis, A.; Plukiene, R. [Inst. of Physics, Savanoriu pr. 231, 02300 Vilnius (Lithuania); Prevost, A. [CEA Saclay, DSM/DAPNIA, 91191 Gif-sur-Yvette (France); Shcherbakov, O.; Vorobyev, A. [Petersburg Nuclear Physics Inst., Leningrad district, 188350 Gatchina (Russian Federation)

    2006-07-01T23:59:59.000Z

    This paper presents the preliminary results on measured delayed neutron (DN) yields and time spectra from 1 GeV protons interacting with thick {sup nat}Pb targets. In parallel, the MCNPX and PHTTS codes were used to predict the DN precursors and construct the theoretical DN tables. Different model parameters are examined and show significant dependence on the choice of the intra-nuclear cascade and fission-evaporation models used. These data and modeling are of great importance for the new generation spallation neutron sources based on liquid metal technologies where a significant amount of the DN precursor activity can be accumulated in the target fluid. (authors)

  19. Annealing temperature and barrier thickness effect on the structural and optical properties of silicon nanocrystals/SiO{sub 2} superlattices

    SciTech Connect (OSTI)

    López-Vidrier, J., E-mail: jlopezv@el.ub.edu; Hernández, S.; López-Conesa, L.; Peiró, F.; Garrido, B. [MIND–IN2UB, Electronics Department, University of Barcelona, Martí i Franquès 1, E–08028 Barcelona (Spain); Hiller, D.; Gutsch, S.; Zacharias, M. [IMTEK, Faculty of Engineering, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 103, D-79110 Freiburg (Germany); Estradé, S. [MIND–IN2UB, Electronics Department, University of Barcelona, Martí i Franquès 1, E–08028 Barcelona (Spain); TEM–MAT, CCiT–UB, Scientific and Technological Center - University of Barcelona, Solé i Sabarís 1, E–08028 Barcelona (Spain)

    2014-10-07T23:59:59.000Z

    The effect of the annealing temperature and the SiO{sub 2} barrier thickness of silicon nanocrystal (NC)/SiO{sub 2} superlattices (SLs) on their structural and optical properties is investigated. Energy-filtered transmission electron microscopy (TEM) revealed that the SL structure is maintained for annealing temperatures up to 1150?°C, with no variation on the nanostructure morphology for different SiO{sub 2} barrier thicknesses. Nevertheless, annealing temperatures as high as 1250?°C promote diffusion of Si atoms into the SiO{sub 2} barrier layers, which produces larger Si NCs and the loss of the NC size control expected from the SL approach. Complementary Raman scattering measurements corroborated these results for all the SiO{sub 2} and Si-rich oxynitride layer thicknesses. In addition, we observed an increasing crystalline fraction up to 1250?°C, which is related to a decreasing contribution of the suboxide transition layer between Si NCs and the SiO{sub 2} matrix due to the formation of larger NCs. Finally, photoluminescence measurements revealed that the emission of the superlattices exhibits a Gaussian-like lineshape with a maximum intensity after annealing at 1150?°C, indicating a high crystalline degree in good agreement with Raman results. Samples submitted to higher annealing temperatures display a progressive emission broadening, together with an increase in the central emission wavelength. Both effects are related to a progressive broadening of the size distribution with a larger mean size, in agreement with TEM observations. On the other hand, whereas the morphology of the Si NCs is unaffected by the SiO{sub 2} barrier thickness, the emission properties are slightly modified. These observed modifications in the emission lineshape allow monitoring the precipitation process of Si NCs in a direct non-destructive way. All these experimental results evidence that an annealing temperature of 1150?°C and 1-nm SiO{sub 2} barrier can be reached whilst preserving the SL structure, being thus the optimal structural SL parameters for their use in optoelectronics.

  20. A microstructural approach toward the effect of thickness on semiconductor-to-metal transition characteristics of VO{sub 2} epilayers

    SciTech Connect (OSTI)

    Molaei, R., E-mail: rmolaei@ncsu.edu; Wu, F.; Narayan, J. [Department of Materials Science and Engineering, North Carolina State University, EB-1, Raleigh, North Carolina 27695-7907 (United States); Bayati, R. [Intel Corporation, IMO-SC, SC2, Santa Clara, California 95054 (United States)

    2014-04-28T23:59:59.000Z

    We report the control of semiconductor to metal transition in VO{sub 2}(010) epilayers integrated with Si(100) substrates buffered with an NiO[111]/YSZ[100] intermediate layer. VO{sub 2} epitaxial thin films were grown at different thicknesses varying from 10 to 200?nm using pulsed laser deposition technique. An epitaxial relationship of VO{sub 2}(010)?NiO(111)? YSZ(001)?Si(001) and VO{sub 2}[100]?NiO[110]? YSZ[100]?Si[100] was established at room temperature. The crystallographic alignment across the VO{sub 2}/NiO interface changes to VO{sub 2}(100)?NiO(111) and VO{sub 2}[001]?NiO[110] at the temperature of growth giving rise to a misfit strain of about 33.5% and 3.0% along two orthogonal in-plane orientations. The transition temperature was observed to vary from about 353 to 341?K, the transition amplitude increased by about five orders of magnitude, and the hysteresis decreased to about 3?K, as the thickness of VO{sub 2} layers increased from about 10 to 200?nm. These observations were explained based on strain characteristics, overall defect content and grain boundaries, and phenomenological thermodynamic models.