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Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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1

Doping of gallium nitride using disilane  

Science Conference Proceedings (OSTI)

Keywords: disilane, gallium nitride, metalorganic chemical vapor deposition, organometallic vapor phase epitaxy, silicon doping

A. E. Wickenden; L. B. Rowland; K. Doverspike; D. K. Gaskill; J. A. Freitas, Jr.; D. S. Simons; P. H. Chi

1995-11-01T23:59:59.000Z

2

Gallium Nitride nanowires: synthesis, contacts, electron ...  

Science Conference Proceedings (OSTI)

... Gallium Nitride nanowires: synthesis, contacts, electron transport, mechanical resonators, and defects. John E. Fischer University of Pennsylvania. ...

3

P-type gallium nitride  

DOE Patents (OSTI)

Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5{times}10{sup 11} /cm{sup 3} and hole mobilities of about 500 cm{sup 2} /V-sec, measured at 250 K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al. 9 figs.

Rubin, M.; Newman, N.; Fu, T.; Ross, J.; Chan, J.

1997-08-12T23:59:59.000Z

4

P-type gallium nitride  

DOE Patents (OSTI)

Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5.times.10.sup.11 /cm.sup.3 and hole mobilities of about 500 cm.sup.2 /V-sec, measured at 250.degree. K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al.

Rubin, Michael (Berkeley, CA); Newman, Nathan (Montara, CA); Fu, Tracy (Berkeley, CA); Ross, Jennifer (Pleasanton, CA); Chan, James (Berkeley, CA)

1997-01-01T23:59:59.000Z

5

Electrochemical Solution Growth: Gallium Nitride Crystal ...  

... and economical bulk gallium nirtide (GaN) substrates needed to meet the performance requirements of high-efficiency LED and high-power transistors.

6

Characterizing organometallic-vapor-phase-epitaxy-grown indium gallium nitride islands on gallium nitride for light emitting diode applications.  

E-Print Network (OSTI)

??The indium-gallium-nitride on gallium-nitride (InGaN/GaN) materials system is a promising candidate for providing a high intensity, high efficiency solution to the yet unsolved problem of… (more)

Anderson, Kathy Perkins Jenkins

2011-01-01T23:59:59.000Z

7

Solar cell with a gallium nitride electrode  

DOE Patents (OSTI)

A solar cell which comprises a body of silicon having a P-N junction therein with a transparent conducting N-type gallium nitride layer as an ohmic contact on the N-type side of the semiconductor exposed to solar radiation.

Pankove, Jacques I. (Princeton, NJ)

1979-01-01T23:59:59.000Z

8

Size and shape dependence on melting temperature of gallium nitride nanoparticles  

Science Conference Proceedings (OSTI)

The study of variation of the size and shape effect on the melting property of gallium nitride nanoparticles with their spherical and cylindrical geometrical feature is theoretically explored. A numerical thermodynamical model has been devoted for the ...

Paneerselvam Antoniammal; Dakshanamoorthy Arivuoli

2012-01-01T23:59:59.000Z

9

Development of a Bulk GaN Growth Technique for Low Defect Density...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Enabling Next-Generation Power Electronics: Electrochemical Solution Growth (ESG) Technique for Bulk Gallium Nitride Substrates Karen Waldrip Dept. 2546, Advanced Power Sources R&D...

10

Formation mechanisms of spatially-directed zincblende gallium nitride nanocrystals  

Science Conference Proceedings (OSTI)

We report on the spatially selective formation of GaN nanocrystals embedded in GaAs. Broad-area N{sup +} implantation followed by rapid thermal annealing leads to the formation of nanocrystals at the depth of maximum ion damage. With additional irradiation using a Ga{sup +} focused ion beam, selective lateral positioning of the nanocrystals within the GaAs matrix is observed in isolated regions of increased vacancy concentration. Following rapid thermal annealing, the formation of zincblende GaN is observed in the regions of highest vacancy concentration. The nucleation of zincblende nanocrystals over the wurtzite phase of bulk GaN is consistent with the predictions of a thermodynamic model for the nanoscale size-dependence of GaN nucleation.

Wood, A. W. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Collino, R. R. [Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Cardozo, B. L. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Naab, F. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Wang, Y. Q. [Materials Science and Technology Division, Los Alamos National Lab, Los Alamos, New Mexico 87545 (United States); Goldman, R. S. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2011-12-15T23:59:59.000Z

11

Gallium-Nitride Transistors for High-Efficiency Industrial Power Supplies, Phase 1: State of Semiconductor Development and Industrial Power Supply Market  

Science Conference Proceedings (OSTI)

This white paper describes recent advancements in the development of Gallium-Nitride (GaN) transistors for power conversion applications. This wide bandgap semiconductor has the potential to reduce losses and improve performance of power converters. The industrial power supply market is described and the application of GaN to power conversion in this segment is introduced for future work.

2013-12-23T23:59:59.000Z

12

Compact, Interactive Electric Vehicle Charger: Gallium-Nitride Switch Technology for Bi-directional Battery-to-Grid Charger Applications  

SciTech Connect

ADEPT Project: HRL Laboratories is using gallium nitride (GaN) semiconductors to create battery chargers for electric vehicles (EVs) that are more compact and efficient than traditional EV chargers. Reducing the size and weight of the battery charger is important because it would help improve the overall performance of the EV. GaN semiconductors process electricity faster than the silicon semiconductors used in most conventional EV battery chargers. These high-speed semiconductors can be paired with lighter-weight electrical circuit components, which helps decrease the overall weight of the EV battery charger. HRL Laboratories is combining the performance advantages of GaN semiconductors with an innovative, interactive battery-to-grid energy distribution design. This design would support 2-way power flow, enabling EV battery chargers to not only draw energy from the power grid, but also store and feed energy back into it.

2010-10-01T23:59:59.000Z

13

Silicon surface and bulk defect passivation by low temperature PECVD oxides and nitrides  

DOE Green Energy (OSTI)

The effectiveness of PECVD passivation of surface and bulk defects in Si, as well as phosphorous diffused emitters, Is investigated and quantified. Significant hydrogen incorporation coupled with high positive charge density in the PECVD SiN layer is found to play an important role in bulk and surface passivation. It is shown that photo-assisted anneal in a forming gas ambient after PECVD depositions significantly improves the passivation of emitter and bulk defects. PECVD passivation of phosphorous doped emitters and boron doped bare Si surfaces is found to be a strong function of doping concentration. Surface recombination velocity of less than 200 cm/s for 0.2 Ohm-cm and less than 1 cm/s for high resistivity substrates ({approximately} Ohm-cm) were achieved. PECVD passivation improved bulk lifetime in the range of 30% to 70% in multicrystalline Si materials. However, the degree of the passivation was found to be highly material specific. Depending upon the passivation scheme, emitter saturation current density (J{sub oe}) can be reduced by a factor of 3 to 9. Finally, the stability of PECVD oxide/nitride passivation under prolonged UV exposure is established.

Chen, Z.; Rohatgi, A. [Georgia Institute of Technology, Atlanta, GA (United States). Univ. Center of Excellence for Photovoltaics Research and Education; Ruby, D. [Sandia National Labs., Albuquerque, NM (United States)

1995-01-01T23:59:59.000Z

14

Structure and electronic properties of saturated and unsaturated gallium nitride nanotubes  

DOE Green Energy (OSTI)

The atomic and electronic structures of saturated and unsaturated GaN nanotubes along the [001] direction with (100) lateral facets are studied using first-principles calculations. Atomic relaxation of nanotubes shows that appreciable distortion occurs in the unsaturated nanotubes. All the nanotubes considered, including saturated and unsaturated ones, exhibit semiconducting, with a direct band gap. Surface states arisen from the threefold-coordinated N and Ga atoms at the lateral facets exist inside the bulk-like band gap. When the nanotubes saturated with hydrogen, these dangling bond bands are removed from the band gap, but the band gap decreases with increasing the wall thickness of the nanotubes.

Wang, Zhiguo; Wang, Shengjie; Li, Jingbo; Gao, Fei; Weber, William J.

2009-11-05T23:59:59.000Z

15

The effect of hydrogen-plasma and PECVD-nitride deposition on bulk and surface passivation in string-ribbon silicon solar cells  

DOE Green Energy (OSTI)

We have investigated whether an in-situ hydrogen or ammonia rf-plasma treatment prior to a PECVD-nitride deposition would promote bulk defect passivation independently of surface effects. We also studied whether the predeposition of a thin silicon-nitride protective layer vbefore performing the plasma treatment would serve to minimize surface damage. We found that for the limited set of deposition conditions in of cells processed using the used five different deposition strategies and compared the resulting cell performance with that investigated so far, the direct deposition of PECVD-nitride produces the best cells on String Ribbon silicon wafers to date, with efficiencies up to 14.5%. Hydrogen and ammonia plasma pretreatments without a protective nitride layer resulted in better bulk passivation, but damaged surfaces. Pretreatments after deposition of the protective layer produced the best surface passivation, but were not effective in passivating the bulk.

Ruby, D.S. [Sandia National Labs., Albuquerque, NM (United States); Wilbanks, W.L.; Fleddermann, C.B. [New Mexico Univ., Albuquerque, NM (United States); Hanoka, J.I. [Evergreen Solar Inc., Waltham, MA (United States)

1995-12-01T23:59:59.000Z

16

Superconducting structure with layers of niobium nitride and aluminum nitride  

DOE Patents (OSTI)

A superconducting structure is formed by depositing alternate layers of aluminum nitride and niobium nitride on a substrate. Deposition methods include dc magnetron reactive sputtering, rf magnetron reactive sputtering, thin-film diffusion, chemical vapor deposition, and ion-beam deposition. Structures have been built with layers of niobium nitride and aluminum nitride having thicknesses in a range of 20 to 350 Angstroms. Best results have been achieved with films of niobium nitride deposited to a thickness of approximately 70 Angstroms and aluminum nitride deposited to a thickness of approximately 20 Angstroms. Such films of niobium nitride separated by a single layer of aluminum nitride are useful in forming Josephson junctions. Structures of 30 or more alternating layers of niobium nitride and aluminum nitride are useful when deposited on fixed substrates or flexible strips to form bulk superconductors for carrying electric current. They are also adaptable as voltage-controlled microwave energy sources. 8 figs.

Murduck, J.M.; Lepetre, Y.J.; Schuller, I.K.; Ketterson, J.B.

1989-07-04T23:59:59.000Z

17

Structural TEM study of nonpolar a-plane gallium nitride grown on (112_0) 4H-SiC by organometallic vapor phase epitaxy  

E-Print Network (OSTI)

nitride grown on (1120) 4H-SiC by organometallic vapor phasea-plane GaN grown on a 4H-SiC substrate with an AlN buffergrown on (0001) Al 2 O 3 , 6H-SiC or free- standing GaN

Zakharov, Dmitri N.; Liliental-Weber, Zuzanna; Wagner, Brian; Reitmeier, Zachary J.; Preble, Edward A.; Davis, Robert F.

2005-01-01T23:59:59.000Z

18

Ammothermal Growth of Gan Substrates For Leds: High-Pressure Ammonothermal Process for Bulk Gallium Nitride Crystal Growth for Energy Efficient Commercially Competitive Lighting  

Science Conference Proceedings (OSTI)

Broad Funding Opportunity Announcement Project: The new GaN crystal growth method is adapted from that used to grow quartz crystals, which are very inexpensive and represent the second-largest market for single crystals for electronic applications (after silicon). More extreme conditions are required to grow GaN crystals and therefore a new type of chemical growth chamber was invented that is suitable for large-scale manufacturing. A new process was developed that grows GaN crystals at a rate that is more than double that of current processes. The new technology will enable GaN substrates with best-in-world quality at lowest-in-world prices, which in turn will enable new generations of white LEDs, lasers for full-color displays, and high-performance power electronics.

None

2011-01-01T23:59:59.000Z

19

Oxidation of gallium arsenide  

DOE Patents (OSTI)

This invention relates to gallium arsenide semiconductors and, more particularly, to the oxidation of surface layers of gallium arsenide semiconductors for semiconductor device fabrication.

Hoffbauer, M.A.; Cross, J.B.

1991-11-16T23:59:59.000Z

20

Controlling Gallium Nitride Polarity on Native Substrates  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and Power Conversion ... Potential Ceramic Dielectrics for Air Force Applications.

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Electronic properties of gallium nitride nanowires  

E-Print Network (OSTI)

This thesis presents a systematic study of the electrical transport in GaN nanowires. Particularly, the effect of the surrounding dielectric on the conductivity of GaN nanowires is experimentally shown for the first time. ...

Yoon, Joonah

2008-01-01T23:59:59.000Z

22

Development of gallium nitride power transistors  

E-Print Network (OSTI)

GaN-based high-voltage transistors have outstanding properties for the development of ultra-high efficiency and compact power electronics. This thesis describes a new process technology for the fabrication of GaN power ...

Piedra, Daniel, M. Eng. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

23

Development of a Bulk GaN Growth Technique for Low Defect Density, Large-Area Native Substrates  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Next-Generation Power Electronics: Next-Generation Power Electronics: Electrochemical Solution Growth (ESG) Technique for Bulk Gallium Nitride Substrates Karen Waldrip Dept. 2546, Advanced Power Sources R&D Sandia National Labs, Albuquerque, NM knwaldr@sandia.gov, (505) 844-1619 Acknowledgements: Mike Soboroff, Stan Atcitty, Nancy Clark, and John Boyes David Ingersoll, Frank Delnick, and Travis Anderson 2010 DOE Peer Review, Nov. 2-4, Washington, DC Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Funded by the Energy Storage Systems Program of the U.S. Department Of Energy through Sandia National Laboratories Project Objective

24

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

NLE Websites -- All DOE Office Websites (Extended Search)

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

25

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

NLE Websites -- All DOE Office Websites (Extended Search)

Vacancy-Induced Nanoscale Wire Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Wednesday, 21 December 2005 00:00 Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

26

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

NLE Websites -- All DOE Office Websites (Extended Search)

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

27

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

NLE Websites -- All DOE Office Websites (Extended Search)

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

28

Electrochemical investigation of the gallium nitride-aqueous electrolyte interface  

SciTech Connect

GaN (E{sub g} = {approximately}3.4 eV) was photoelectrochemically characterized and the energetic position of its bandedges determined with respect to SHE. Electrochemical impedance spectroscopy was employed to analyze the interface, determine the space charge layer capacitance, and, subsequently obtain the flatband potential of GaN in different aqueous electrolytes. The flatband potential of GaN varied at an approximately Nernstian rate in aqueous buffer electrolytes of different pHs indicating acid-base equilibria at the interface.

Kocha, S.S.; Peterson, M.W.; Arent, D.J.; Turner, J.A. [National Renewable Energy Lab., Golden, CO (United States). Photoconversion Branch; Redwing, J.M.; Tischler, M.A. [Advanced Technology Materials, Inc., Danbury, CT (United States)

1995-12-01T23:59:59.000Z

29

Nanoscale-Structured Gallium Nitride Pillars for Light-Emitting ...  

Science Conference Proceedings (OSTI)

... using top-down fabrication scheme, D. Paramanik, A. Motayed, GS Aluri, J.-Y. Ha, S. Krylyuk, AV Davydov, M. King, S. McLaughlin, S. Gupta, and H ...

2013-01-18T23:59:59.000Z

30

Nanofabrication of gallium nitride photonic crystal light-emitting diodes  

Science Conference Proceedings (OSTI)

We describe a comparison of nanofabrication technologies for the fabrication of 2D photonic crystal structures on GaN/InGaN blue LEDs. Such devices exhibit enhanced brightness and the possibility of controlling the angular emission profile of emitted ... Keywords: GaN dry-etching, Light-emitting diodes, Nanolithography, Photonic crystals

Ali Z. Khokhar; Keith Parsons; Graham Hubbard; Faiz Rahman; Douglas S. Macintyre; Chang Xiong; David Massoubre; Zheng Gong; Nigel P. Johnson; Richard M. De La Rue; Ian M. Watson; Erdan Gu; Martin D. Dawson; Steve J. Abbott; Martin D. B. Charlton; Martin Tillin

2010-11-01T23:59:59.000Z

31

Preparation of uranium nitride  

DOE Patents (OSTI)

A process for preparing actinide-nitrides from massive actinide metal which is suitable for sintering into low density fuel shapes by partially hydriding the massive metal and simultaneously dehydriding and nitriding the dehydrided portion. The process is repeated until all of the massive metal is converted to a nitride.

Potter, Ralph A. (Lynchburg, VA); Tennery, Victor J. (Upper Arlington, OH)

1976-01-01T23:59:59.000Z

32

Gallium interactions with Zircaloy  

E-Print Network (OSTI)

High fluence ion implantation of Ga ions was conducted ics. on heated Zircaloy-4 in the range of [] Ga ions/[]. Surface effects were studied using SEM and electron microphone analysis. The depth profile of Ga in the Zircaloy was characterized with Rutherford backscattering and SIMS techniques. Results indicate that the Zirc-4 is little affected up to a fluency of [] Ga ions/[]. After implantation of [] Ga ions/[], sub-grain features on the order of 2 gm were observed which may be due to intermetallic compound formation between Ga and Zr. For the highest fluency implant, Ga content in the Zirc-4 reached a saturation value of between 30 and 40 atomic %; significant enhanced diffusion was observed but gallium was not seen to concentrate at grain boundaries.

West, Michael Keith

1998-01-01T23:59:59.000Z

33

SYNTHESIS OF HIGH-PURITY BULK COPPER INDIUM GALLIUM SELENIDE ...  

A sputtering target formed by the method can have an oxygen content of 10 ppm by weight, ... Biomass and Biofuels; Building Energy Efficiency; Electricity Transmission;

34

Study of liquid gallium at high pressure using synchrotron x-ray  

SciTech Connect

Liquid gallium has been studied at high pressure up to 2 GPa and ambient temperature in a diamond anvil cell using high energy synchrotron x-ray beam. The total x-ray scattering data of liquid gallium were collected up to Q = 12 A{sup -1} and analyzed using pair distribution functions (PDF). The results indicate that the first nearest neighbor peak and second nearest neighbor (shoulder) peak of PDF in liquid gallium does not change with pressure, whereas the higher order (i.e., third and fourth) nearest neighbor peaks shift towards shorter distance with increasing pressure. Reverse Monte Carlo modeling based on the observed data shows that the coordination number in the liquid gallium increases with pressure from 10.5 at 0.3 GPa to 11.6 at 2 GPa. An atomic arrangement similar to the crystalline phase of Ga(II) with coordination number of 12 is proposed for the locally dense-packed rigid unit in liquid gallium. The volume compression data derived from the structure modeling yield a bulk modulus of 12.1(6) GPa for liquid gallium.

Yu, Tony; Guo Quanzhong; Parise, John [Department of Geosciences, Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794-2100 (United States); Chen Jiuhua [Department of Geosciences, Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794-2100 (United States); Department of Mechanical and Materials Engineering, Center for the Study of Matters at Extreme Conditions, Florida International University, Miami, Florida 33199 (United States); Ehm, Lars [Department of Geosciences, Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794-2100 (United States); National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States); Huang Shu [Department of Mechanical and Materials Engineering, Center for the Study of Matters at Extreme Conditions, Florida International University, Miami, Florida 33199 (United States); Luo Shengnian [Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2012-06-01T23:59:59.000Z

35

Nitride fuel performance  

E-Print Network (OSTI)

The purpose of this work was to assess the potential of nitride fuels in the current context of the nuclear industry. Nitride fuels systems have indeed been for the past decade the subject of new interest from the international community. This renewal of interest can be explained by the strong potential that nitride fuel systems exhibit for applications such as advanced fast reactor technology, waste transmutation and nuclear space power. To assess this potential, a review of the nitride physical properties was performed in comparison to oxide or metal fuel properties. The potential applications of nitride systems were also detailed. A fuel performance computer code was developed to obtain a more quantitative comparison between nitride and oxide fuel. The oxide code FUELROD was taken as a basis for the new code. After modernization, nitride fuel property correlations were implemented to obtain a nitride version of the code. Using this new tool, a comparison between oxide and nitride fuels was performed to highlight their difference in irradiation behavior in order to confirm their potential.

Reynaud, Sylvie Marie Aurel?ie

2002-01-01T23:59:59.000Z

36

Synthesis, characterization, and biotemplated assembly of indium nitride and indium gallium nitride nanoparticles  

E-Print Network (OSTI)

A low-temperature, ambient pressure solution synthesis of colloidal InN nanoparticles is presented. This synthesis utilizes a previously dismissed precursor and results in individual, non-aggregated nanoparticles with ...

Hsieh, Jennifer Chia-Jen

2010-01-01T23:59:59.000Z

37

Effect of magnetic field on the mechanical properties of magnetostrictive iron-gallium nanowires  

SciTech Connect

This study experimentally investigates the elastic properties of individual iron-gallium nanowires with and without an applied magnetic bias field. The experiments were conducted with a custom manipulator stage designed for use within a scanning electron microscope, where nanowires were mechanically tested both statically and dynamically. Experiments were also performed in the presence of a 20 Oe dc magnetic field in order to identify any variation in wire properties. The results suggest that iron-gallium nanowires possess an elastic modulus very similar to the macroscale value, tensile strengths of more than double the bulk material, and minor magnetic field induced stiffening at low stresses.

Downey, Patrick R.; Flatau, Alison B. [Department of Aerospace Engineering, University of Maryland, 3181 Martin Hall, College Park, Maryland 20742 (United States); McGary, Patrick D.; Stadler, Bethanie J. H. [Department of Electrical and Computer Engineering, University of Minnesota, 200 Union St., Minneapolis, Minnesota 55455 (United States)

2008-04-01T23:59:59.000Z

38

Synthesis and characterization of visible emission from rare-earth doped aluminum nitride, gallium nitride and gallium aluminum nitride powders and thin films  

E-Print Network (OSTI)

to improve sealing and prevent the ingress of air, as shownimproved sealing and prevented the ingress of air, which

Tao, Jonathan Huai-Tse

2010-01-01T23:59:59.000Z

39

Boron nitride nanotubes  

Science Conference Proceedings (OSTI)

Boron nitride nanotubes are prepared by a process which includes: (a) creating a source of boron vapor; (b) mixing the boron vapor with nitrogen gas so that a mixture of boron vapor and nitrogen gas is present at a nucleation site, which is a surface, the nitrogen gas being provided at a pressure elevated above atmospheric, e.g., from greater than about 2 atmospheres up to about 250 atmospheres; and (c) harvesting boron nitride nanotubes, which are formed at the nucleation site.

Smith, Michael W. (Newport News, VA); Jordan, Kevin (Newport News, VA); Park, Cheol (Yorktown, VA)

2012-06-06T23:59:59.000Z

40

Decreased gallium uptake in acute hematogenous osteomyelitis  

SciTech Connect

Decreased radiopharmaceutical uptake was noted on both bone and gallium scans in the case of acute hematogenous osteomyelitis of the right ilium (acetabular roof). This combination of findings is probably rare. The mechanism of decreased gallium uptake is unknown, but may be related to decreased blood flow.

Ang, J.G.; Gelfand, M.J.

1983-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Cubic nitride templates  

DOE Patents (OSTI)

A polymer-assisted deposition process for deposition of epitaxial cubic metal nitride films and the like is presented. The process includes solutions of one or more metal precursor and soluble polymers having binding properties for the one or more metal precursor. After a coating operation, the resultant coating is heated at high temperatures under a suitable atmosphere to yield metal nitride films and the like. Such films can be used as templates for the development of high quality cubic GaN based electronic devices.

Burrell, Anthony K; McCleskey, Thomas Mark; Jia, Quanxi; Mueller, Alexander H; Luo, Hongmei

2013-04-30T23:59:59.000Z

42

Bulk Metallic Glasses XI  

Science Conference Proceedings (OSTI)

Jul 15, 2013 ... A Bulk Metallic Glass with Record-breaking Damage Tolerance ... Oxidation on the Surface Characteristics of Zr-based Bulk Metallic Glasses.

43

Superplastic forging nitride ceramics  

DOE Patents (OSTI)

The invention relates to producing relatively flaw free silicon nitride ceramic shapes requiring little or no machining by superplastic forging This invention herein was made in part under Department of Energy Grant DE-AC01-84ER80167, creating certain rights in the United States Government. The invention was also made in part under New York State Science and Technology Grant SB1R 1985-10.

Panda, Prakash C. (Ithaca, NY); Seydel, Edgar R. (Ithaca, NY); Raj, Rishi (Ithaca, NY)

1988-03-22T23:59:59.000Z

44

Silicon nitride ceramic comprising samaria and ytterbia  

Science Conference Proceedings (OSTI)

This invention relates to a sintered silicon nitride ceramic comprising samaria and ytterbia for enhanced toughness.

Yeckley, Russell L. (Oakham, MA)

1996-01-01T23:59:59.000Z

45

Cordierite silicon nitride filters  

SciTech Connect

The objective of this project was to develop a silicon nitride based crossflow filter. This report summarizes the findings and results of the project. The project was phased with Phase I consisting of filter material development and crossflow filter design. Phase II involved filter manufacturing, filter testing under simulated conditions and reporting the results. In Phase I, Cordierite Silicon Nitride (CSN) was developed and tested for permeability and strength. Target values for each of these parameters were established early in the program. The values were met by the material development effort in Phase I. The crossflow filter design effort proceeded by developing a macroscopic design based on required surface area and estimated stresses. Then the thermal and pressure stresses were estimated using finite element analysis. In Phase II of this program, the filter manufacturing technique was developed, and the manufactured filters were tested. The technique developed involved press-bonding extruded tiles to form a filter, producing a monolithic filter after sintering. Filters manufactured using this technique were tested at Acurex and at the Westinghouse Science and Technology Center. The filters did not delaminate during testing and operated and high collection efficiency and good cleanability. Further development in areas of sintering and filter design is recommended.

Sawyer, J.; Buchan, B. (Acurex Environmental Corp., Mountain View, CA (United States)); Duiven, R.; Berger, M. (Aerotherm Corp., Mountain View, CA (United States)); Cleveland, J.; Ferri, J. (GTE Products Corp., Towanda, PA (United States))

1992-02-01T23:59:59.000Z

46

Method for Plutonium-Gallium Separation by Anodic Dissolution of a Solid Plutonium-Gallium Alloy  

DOE Patents (OSTI)

Purified plutonium and gallium are efficiently recovered from a solid plutonium-gallium (Pu-Ga) alloy by using an electrorefining process. The solid Pu-Ga alloy is the cell anode, preferably placed in a moving basket within the electrolyte. As the surface of the Pu-Ga anode is depleted in plutonium by the electrotransport of the plutonium to a cathode, the temperature of the electrolyte is sufficient to liquify the surface, preferably at about 500 C, resulting in a liquid anode layer substantially comprised of gallium. The gallium drips from the liquified surface and is collected below the anode within the electrochemical cell. The transported plutonium is collected on the cathode surface and is recovered.

Miller, William E.; Tomczuk, Zygmunt

1998-12-08T23:59:59.000Z

47

Bulk Metallic Glasses X  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... Aerospace and Spacecraft Applications for Bulk Metallic Glasses and Matrix Composites · Air Oxidation of a Binary Cu64.5Zr35.5 Bulk Metallic ...

48

Hard carbon nitride and method for preparing same  

DOE Patents (OSTI)

Novel crystalline .alpha. (silicon nitride-like)-carbon nitride and .beta. (silicon nitride-like)-carbon nitride are formed by sputtering carbon in the presence of a nitrogen atmosphere onto a single crystal germanium or silicon, respectively, substrate.

Haller, Eugene E. (Berkeley, CA); Cohen, Marvin L. (Berkeley, CA); Hansen, William L. (Walnut Creek, CA)

1992-01-01T23:59:59.000Z

49

Rotary bulk solids divider  

DOE Patents (OSTI)

An apparatus for the disbursement of a bulk solid sample comprising, a gravity hopper having a top open end and a bottom discharge end, a feeder positioned beneath the gravity hopper so as to receive a bulk solid sample flowing from the bottom discharge end, and a conveyor receiving the bulk solid sample from the feeder and rotating on an axis that allows the bulk solid sample to disperse the sample to a collection station.

Maronde, Carl P. (McMurray, PA); Killmeyer, Jr., Richard P. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

50

Gallium-positive Lyme disease myocarditis  

Science Conference Proceedings (OSTI)

In the course of a work-up for fever of unknown origin associated with intermittent arrhythmias, a gallium scan was performed which revealed diffuse myocardial uptake. The diagnosis of Lyme disease myocarditis subsequently was confirmed by serologic titers. One month following recovery from the acute illness, the abnormal myocardial uptake completely resolved.

Alpert, L.I.; Welch, P.; Fisher, N.

1985-09-01T23:59:59.000Z

51

Method for producing refractory nitrides  

DOE Patents (OSTI)

Disclosed is a process for making fine, uniform metal nitride powders that can be hot pressed or sintered. A metal salt is placed in a solvent with Melamine and warmed until a metal-Melamine compound forms. The solution is cooled and the metal-Melamine precipitate is calcined at a temperature below 700/sup 0/C to form the metal nitrides and to avoid formation of the metal oxide.

Quinby, T.C.

1986-04-09T23:59:59.000Z

52

Gallium 67 scintigraphy in glomerular disease  

Science Conference Proceedings (OSTI)

To evaluate the diagnostic usefulness of gallium 67 scintigraphy in glomerular disease, 45 patients with various glomerulopathies, excluding lupus nephritis and renal vasculitis, were studied. Persistent renal visualization 48 hours after the gallium injection, a positive scintigram, was graded as + (less than), ++ (equal to), and +++ (greater than) the hepatic uptake. Positive scintigrams were seen in ten of 16 cases of focal segmental glomerulosclerosis, six of 11 cases of proliferative glomerulonephritis, and one case of minimal change, and one of two cases of membranous nephropathy; also in three of six cases of sickle glomerulopathy, two cases of diabetic neuropathy, one of two cases of amyloidosis, and one case of mild chronic allograft rejection. The 25 patients with positive scans were younger than the 20 with negative scans (31 +/- 12 v 42 +/- 17 years; P less than 0.01), and exhibited greater proteinuria (8.19 +/- 7.96 v 2.9 +/- 2.3 S/d; P less than 0.01) and lower serum creatinine values (2 +/- 2 v 4.1 +/- 2.8 mg/dL; P less than 0.01). The amount of proteinuria correlated directly with the intensity grade of the gallium image (P less than 0.02), but there was no correlation between the biopsy diagnosis and the outcome of the gallium scan. It was concluded that gallium scintigraphy is not useful in the differential diagnosis of the glomerular diseases under discussion. Younger patients with good renal function and heavy proteinuria are likely to have a positive renal scintigram regardless of the underlying glomerulopathy.

Bakir, A.A.; Lopez-Majano, V.; Levy, P.S.; Rhee, H.L.; Dunea, G.

1988-12-01T23:59:59.000Z

53

Controlled VLS Growth of Indium, Gallium and Tin Oxide Nanowires via Chemical Vapor Transport  

E-Print Network (OSTI)

technique to synthesize indium oxide, gallium oxide, and tinmaterial systems such as indium oxide, gallium oxide and tinand Characterization A. Indium Oxide Nanowires Indium oxide

Johnson, M.C.; Aloni, S.; McCready, D.E.; Bourret-Courchesne, E.D.

2006-01-01T23:59:59.000Z

54

Survey of the market, supply and availability of gallium  

DOE Green Energy (OSTI)

The objective of this study was to assess the present consumption and supply of gallium, its potential availability in the satellite power system (SPS) implementation time frame, and commercial and new processing methods for increasing the production of gallium. Findings are reported in detail. The findings strongly suggest that with proper long range planning adequate gallium would be available from free-enterprise world supplies of bauxite for SPS implementation.

Rosi, F.D.

1980-07-01T23:59:59.000Z

55

Interactions of Zircaloy cladding with gallium: 1998 midyear status  

Science Conference Proceedings (OSTI)

A program has been implemented to evaluate the effect of gallium in mixed-oxide (MOX) fuel derived from weapons-grade (WG) plutonium on Zircaloy cladding performance. The objective is to demonstrate that low levels of gallium will not compromise the performance of the MOX fuel system in a light-water reactor. The graded, four-phase experimental program was designed to evaluate the performance of prototypic Zircaloy cladding materials against (1) liquid gallium (Phase 1), (2) various concentrations of Ga{sub 2}O{sub 3} (Phase 2), (3) centrally heated surrogate fuel pellets with expected levels of gallium (Phase 3), and (4) centrally heated prototypic MOX fuel pellets (Phase 4). This status report describes the results of a series of tests for Phases 1 and 2. Three types of tests are being performed: (1) corrosion, (2) liquid metal embrittlement, and (3) corrosion-mechanical. These tests will determine corrosion mechanisms, thresholds for temperature and concentration of gallium that may delineate behavioral regimes, and changes in the mechanical properties of Zircaloy. Initial results have generally been favorable for the use of WG-MOX fuel. The MOX fuel cladding, Zircaloy, does react with gallium to form intermetallic compounds at {ge}300 C; however, this reaction is limited by the mass of gallium and is therefore not expected to be significant with a low level (parts per million) of gallium in the MOX fuel. Although continued migration of gallium into the initially formed intermetallic compound can result in large stresses that may lead to distortion, this was shown to be extremely unlikely because of the low mass of gallium or gallium oxide present and expected clad temperatures below 400 C. Furthermore, no evidence for grain boundary penetration by gallium has been observed.

Wilson, D.F.; DiStefano, J.R.; Strizak, J.P.; King, J.F.; Manneschmidt, E.T.

1998-06-01T23:59:59.000Z

56

Interactions of zircaloy cladding with gallium -- 1997 status  

SciTech Connect

A four phase program has been implemented to evaluate the effect of gallium in mixed oxide (MOX) fuel derived from weapons grade (WG) plutonium on Zircaloy cladding performance. The objective is to demonstrate that low levels of gallium will not compromise the performance of the MOX fuel system in LWR. This graded, four phase experimental program will evaluate the performance of prototypic Zircaloy cladding materials against: (1) liquid gallium (Phase 1), (2) various concentrations of Ga{sub 2}O{sub 3} (Phase 2), (3) centrally heated surrogate fuel pellets with expected levels of gallium (Phase 3), and (4) centrally heated prototypic MOX fuel pellets (Phase 4). This status report describes the results of an initial series of tests for phases 1 and 2. Three types of tests are being performed: (1) corrosion, (2) liquid metal embrittlement (LME), and (3) corrosion mechanical. These tests are designed to determine the corrosion mechanisms, thresholds for temperature and concentration of gallium that may delineate behavioral regimes, and changes in mechanical properties of Zircaloy. Initial results have generally been favorable for the use of WG-MOX fuel. The MOX fuel cladding, Zircaloy, does react with gallium to form intermetallic compounds at {ge} 300 C; however, this reaction is limited by the mass of gallium and is therefore not expected to be significant with a low level (in parts per million) of gallium in the MOX fuel. While continued migration of gallium into the initially formed intermetallic compound results in large stresses that can lead to distortion, this is also highly unlikely because of the low mass of gallium or gallium oxide present and expected clad temperatures below 400 C. Furthermore, no evidence for grain boundary penetration by gallium has been observed.

Wilson, D.F.; DiStefano, J.R.; King, J.F.; Manneschmidt, E.T.; Strizak, J.P.

1997-11-01T23:59:59.000Z

57

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide...  

NLE Websites -- All DOE Office Websites (Extended Search)

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward...

58

Gallium uptake by transferrin and interaction with receptor 1  

Science Conference Proceedings (OSTI)

Iron acquisition Á Gallium uptake Á Temperature-jump kinetics .... Part of this thera- peutic action is ..... are all considered as hard metals [10] and are com-.

59

Cold Atoms Could Replace Hot Gallium in Focused Ion ...  

Science Conference Proceedings (OSTI)

... The high energies needed to focus gallium for milling tasks end up burying small amounts in the sample, contaminating the material. ...

2011-04-26T23:59:59.000Z

60

Process for making transition metal nitride whiskers  

DOE Patents (OSTI)

A process for making metal nitrides, particularly titanium nitride whiskers, using a cyanide salt as a reducing agent for a metal compound in the presence of an alkali metal oxide. Sodium cyanide, various titanates and titanium oxide mixed with sodium oxide react to provide titanium nitride whiskers that can be used as reinforcement to ceramic composites. 1 fig., 1 tab.

Bamberger, C.E.

1988-04-12T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Interactions of gallium with zircaloy cladding  

E-Print Network (OSTI)

A mastering system was constructed and installed on the current low energy accelerator of the Ion Beam Laboratory in the Department of Nuclear Engineering. Galium was implanted into heated zircaloy targets at nuances of 3x10ą?, 1x10ą? and 1x10ą? ions/cm˛. Rutherford backscattering spectrometry (RBS) using 260 keV alpha particles was used to determine the initial estimates of gallium concentration. Energy dispersive spectroscopy (EDS) and backscattered electron (BSE) imaging was performed to examine concentration and surface morphology, respectively. Zirconium was then implanted to simulate the radiation effects of fission fragments at a fluency of 1.0x10ą? Zr atoms/cm˛. RBS results showed enhanced diffusion and indicate saturation of the gallium concentration. Results also showed the possible formation of a Ga-Zr compound.

Mitchell, Lee Josey

1999-01-01T23:59:59.000Z

62

Preparation of bulk superhard B-C-N nanocomposite compact  

DOE Patents (OSTI)

Bulk, superhard, B--C--N nanocomposite compacts were prepared by ball milling a mixture of graphite and hexagonal boron nitride, encapsulating the ball-milled mixture at a pressure in a range of from about 15 GPa to about 25 GPa, and sintering the pressurized encapsulated ball-milled mixture at a temperature in a range of from about 1800-2500 K. The product bulk, superhard, nanocomposite compacts were well sintered compacts with nanocrystalline grains of at least one high-pressure phase of B--C--N surrounded by amorphous diamond-like carbon grain boundaries. The bulk compacts had a measured Vicker's hardness in a range of from about 41 GPa to about 68 GPa.

Zhao, Yusheng (Los Alamos, NM); He, Duanwei (Sichuan, CN)

2011-05-10T23:59:59.000Z

63

Diffusion, Uptake and Release of Hydrogen in p-type Gallium Nitride: Theory and Experiment  

DOE Green Energy (OSTI)

The diffusion, uptake, and release of H in p-type GaN are modeled employing state energies from density-function theory and compared with measurements of deuterium uptake and release using nuclear-reaction analysis. Good semiquantitative agreement is found when account is taken of a surface permeation barrier.

MYERS JR.,SAMUEL M.; WRIGHT,ALAN F.; PETERSEN,GARY A.; WAMPLER,WILLIAM R.; SEAGER,CARLETON H.; CRAWFORD,MARY H.; HAN,JUNG

2000-06-27T23:59:59.000Z

64

The equilibrium state of hydrogen in gallium nitride: Theory and experiment  

DOE Green Energy (OSTI)

Formation energies and vibrational frequencies for H in wurtzite GaN were calculated from density functional theory and used to predict equilibrium state occupancies and solid solubilities for p-type, intrinsic, and n-type material. The solubility of deuterium (D) was measured at 600--800 C as a function of D{sub 2} pressure and doping and compared with theory. Agreement was obtained by reducing the H formation energies 0.2 eV from ab-initio theoretical values. The predicted stretch-mode frequency for H bound to the Mg acceptor lies 5% above an observed infrared absorption attributed to this complex. It is concluded that currently recognized H states and physical processes account for the equilibrium behavior of H examined in this work.

MYERS JR.,SAMUEL M.; WRIGHT,ALAN F.; PETERSEN,GARY A.; SEAGER,CARLETON H.; WAMPLER,WILLIAM R.; CRAWFORD,MARY H.; HAN,JUNG

2000-04-17T23:59:59.000Z

65

Radiation-Hardened Gallium Nitride Detector and Arrays for Fusion Diagnostics  

Science Conference Proceedings (OSTI)

This poster reports testing to confirm that GaN devices exhibit the extreme radiation hardness needed for use at the NIF, functioning properly after 1x10{sup 12} protons/cm{sup 2} proton irradiation in one year.

Sun, K. X., and MacNeil, L.

2011-09-08T23:59:59.000Z

66

Commercialization of gallium nitride nanorod arrays on silicon for solid-state lighting  

E-Print Network (OSTI)

One important component in energy usage is lighting, which is currently dominated by incandescent and fluorescent lamps. However, due to potentially higher efficiencies and thus higher energy savings, solid-state lighting ...

Wee, Qixun

2008-01-01T23:59:59.000Z

67

Hanford ETR Bulk Vitrification System - Demonstration Bulk Vitrification  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Bulk Vitrification System - Demonstration Bulk Bulk Vitrification System - Demonstration Bulk Vitrification System (DBVS) Review Report Hanford ETR Bulk Vitrification System - Demonstration Bulk Vitrification System (DBVS) Review Report Full Document and Summary Versions are available for download Hanford ETR Bulk Vitrification System - Demonstration Bulk Vitrification System (DBVS) Review Report Summary - Demonstration Bulk Vitrification System (DBVS) for Low-Actvity Waste at Hanford More Documents & Publications Independent Oversight Activity Report, Hanford Waste Treatment and Immobilization Plant - November 2013 SRS Tank 48H Waste Treatment Project Technology Readiness Assessment External Technical Review for Evaluation of System Level Modeling and Simulation Tools in Support of Hanford Site Liquid Waste Process

68

Large area bulk superconductors  

DOE Patents (OSTI)

A bulk superconductor having a thickness of not less than about 100 microns is carried by a polycrystalline textured substrate having misorientation angles at the surface thereof not greater than about 15.degree.; the bulk superconductor may have a thickness of not less than about 100 microns and a surface area of not less than about 50 cm.sup.2. The textured substrate may have a thickness not less than about 10 microns and misorientation angles at the surface thereof not greater than about 15.degree.. Also disclosed is a process of manufacturing the bulk superconductor and the polycrystalline biaxially textured substrate material.

Miller, Dean J. (Darien, IL); Field, Michael B. (Jersey City, NJ)

2002-01-01T23:59:59.000Z

69

Bulk Metallic Glasses VII  

Science Conference Proceedings (OSTI)

Sponsorship, The Minerals, Metals and Materials Society ... Air-Oxidation of a ( Zr55Cu30Al10Ni5)98Er2 Bulk Metallic Glass at 350-500oc · Anelastic ...

70

High density hexagonal boron nitride prepared by hot isostatic pressing in refractory metal containers  

DOE Patents (OSTI)

Boron nitride powder with less than or equal to the oxygen content of starting powder (down to 0.5% or less) is hot isostatically pressed in a refractory metal container to produce hexagonal boron nitride with a bulk density greater than 2.0 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a cansister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1800{degrees}C and 30 KSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.21 g/cc. Complex shapes can be made.

Hoenig, C.L.

1990-12-31T23:59:59.000Z

71

Behavior of Zircaloy Cladding in the Presence of Gallium  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy has established a dual-track approach to the disposition of plutonium arising from the dismantling of nuclear weapons. Both immobilization and reactor-based mixed-oxide (MOX) fuel technologies are being evaluated. The reactor-based MOX fuel option requires assessment of the potential impact of concentrations of gallium (on the order of 1 to 10 ppm), not present in conventional MOX fuel, on cladding material performance. An experimental program was designed to evaluate the performance of prototypic Zircaloy cladding materials against (1) liquid gallium, and (2) various concentrations of G~03. Three types of tests were performed: (1) corrosion, (2) liquid metal embrittlement, and (3) corrosion-mechanical. These tests were to determine corrosion mechanisms, thresholds for temperature and concentration of gallium that delineate behavioral regimes, and changes in the mechanical properties of Zircaloy. Results have generally been favorable for the use of weapons-grade (WG) MOX fhel. The Zircaloy cladding does react with gallium to form intermetallic compounds at >3000 C; however, this reaction is limited by the mass of gallium and is therefore not expected to be significant with a low level (parts per million) of gallium in the MOX fuel. Furthermore, no evidence for grain boundary penetration by gallium or liquid metal embrittlement was observed.

DiStefano, J.R.; King, J.F.; Manneschmidt, E.T.; Strizak, J.P.; Wilson, D.F.

1998-09-28T23:59:59.000Z

72

Novel Nitride-Modified Multielectron Conversion Electrode ...  

Novel Nitride-Modified Multielectron Conversion Electrode Materials for Lithium Ion Batteries Note: The technology described above is an early stage opportunity.

73

Silicon nitride having a high tensile strength  

Science Conference Proceedings (OSTI)

A ceramic body comprising at least about 80 w/o silicon nitride and having a mean tensile strength of at least about 800 MPa.

Pujari, Vimal K. (Northboro, MA); Tracey, Dennis M. (Medfield, MA); Foley, Michael R. (Oxford, MA); Paille, Norman I. (Oxford, MA); Pelletier, Paul J. (Sutton, MA); Sales, Lenny C. (Grafton, MA); Willkens, Craig A. (Worcester, MA); Yeckley, Russell L. (Latrobe, PA)

1998-01-01T23:59:59.000Z

74

Available Technologies: Synthesizing Boron Nitride Nanotubes and ...  

Nano- & Micro-technology; Software and IT ; Licensing Interest Form Receive Customized Tech Alerts. Synthesizing Boron Nitride Nanotubes and Related Nanoparticles

75

Interactions of Zircaloy Cladding with Gallium: Final Report  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy has established a dual-track approach to the disposition of plutonium arising from the dismantling of nuclear weapons. Both immobilization and reactor-based mixed-oxide (MOX) fuel technologies are being evaluated. The reactor-based MOX fuel option requires assessment of the potential impact of concentrations of gallium (on the order of 1 to 10 ppm), not present in conventional MOX fhel, on cladding material performance. Three previous repmts"3 identified several compatibility issues relating to the presence of gallium in MOX fuel and its possible reaction with fiel cladding. Gallium initially present in weapons-grade (WG) plutonium is largely removed during processing to produce MOX fhel. After blending the plutonium with uranium, only 1 to 10 ppm gallium is expected in the sintered MOX fuel. Gallium present as gallium oxide (G~OJ could be evolved as the suboxide (G~O). Migration of the evolved G~O and diffusion of gallium in the MOX matrix along thermal gradients could lead to locally higher concentrations of G~03. Thus, while an extremely low concentration of gallium in MOX fiel almost ensures a lack of significant interaction of gallium whh Zircaloy fhel cladding, there remains a small probability that corrosion effects will not be negligible. General corrosion in the form of surface alloying resulting from formation of intermetallic compounds between Zircaloy and gallium should be ma& limited and, therefore, superficial because of the expected low ratio of gallium to the surface area or volume of the Zircaloy cladding. Although the expected concentration of gallium is low and there is very limited volubility of gallium in zirconium, especially at temperatures below 700 "C,4 grain boundary penetration and liquid metal embrittlement (LME) are forms of localized corrosion that were also considered. One fuel system darnage mechanism, pellet clad interaction, has led to some failure of the Zircaloy cladding in light-water reactors (LWRS). This has been attributed to stresses in the cladding and one or more aggressive fission products. Stress corrosion cracking by iodines' 6 and LME by cadmium7>8 have been reported, and it is known that Zircaloy can be embrittled by some low-melting metals, (e.g., mercury).g LME is a form of environmentally induced embrittlement that can induce cracking or loss of ductility. LME requties wetting and a tensile stress, but it does not require corrosion penetration. Experimentally, it has been demonstrated that gallium can cause embrittlement of some alloys (e.g., aluminum) at low temperatures,'"' ] ] but experiments relative to LME of zirconium by gallium have been limited and inconclusive.*2 This report describes a series of tests designed to establish the effects of low levels of residual gallium in WG-MOX fhel on its compatibility with Zircaloy. In addition, to establish damage mechanisms it was important to understand types of cladding interactions and available stiety margins with respect to gallium concentration.

D.F. Wilson; E.T. Manneschmidt; J.F. King; J.P. Strizak; J.R. DiStefano

1998-09-01T23:59:59.000Z

76

Effect of oxidation on the Mechanical Properties of Liquid Gallium and Eutectic Gallium-Indium  

E-Print Network (OSTI)

Liquid metals exhibit remarkable mechanical properties, in particular large surface tension and low viscosity. However, these properties are greatly affected by oxidation when exposed to air. We measure the viscosity, surface tension, and contact angle of gallium (Ga) and a eutectic gallium-indium alloy (eGaIn) while controlling such oxidation by surrounding the metal with an acid bath of variable concentration. Rheometry measurements reveal a yield stress directly attributable to an oxide skin that obscures the intrinsic behavior of the liquid metals. We demonstrate how the intrinsic viscosity can be obtained with precision through a scaling technique that collapses low- and high-Reynolds number data. Measuring surface tension with a pendant drop method, we show that the oxide skin generates a surface stress that mimics surface tension and develop a simple model to relate this to the yield stress obtained from rheometry. We find that yield stress, surface tension, and contact angle all transition from solid-...

Xu, Qin; Guo, Qiti; Jaeger, Heinrich; Brown, Eric

2012-01-01T23:59:59.000Z

77

It's Elemental - Isotopes of the Element Gallium  

NLE Websites -- All DOE Office Websites (Extended Search)

Zinc Zinc Previous Element (Zinc) The Periodic Table of Elements Next Element (Germanium) Germanium Isotopes of the Element Gallium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 69 60.108% STABLE 71 39.892% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 56 No Data Available Proton Emission (suspected) No Data Available 57 No Data Available Proton Emission (suspected) No Data Available 58 No Data Available Proton Emission (suspected) No Data Available 59 No Data Available Proton Emission (suspected) No Data Available 60 70 milliseconds Electron Capture 98.40%

78

Method of preparation of uranium nitride  

SciTech Connect

Method for producing terminal uranium nitride complexes comprising providing a suitable starting material comprising uranium; oxidizing the starting material with a suitable oxidant to produce one or more uranium(IV)-azide complexes; and, sufficiently irradiating the uranium(IV)-azide complexes to produce the terminal uranium nitride complexes.

Kiplinger, Jaqueline Loetsch; Thomson, Robert Kenneth James

2013-07-09T23:59:59.000Z

79

Synthesis of transition metal nitride by nitridation of metastable oxide precursor  

SciTech Connect

Metastable transition metal oxides were used as precursors to synthesize transition metal nitrides at low temperature. Amorphous MoO{sub 2} was prepared by reduction of (NH{sub 4}){sub 6}Mo{sub 7}O{sub 24} solution with hydrazine. As-synthesized amorphous MoO{sub 2} was transformed into fcc {gamma}-Mo{sub 2}N at 400 Degree-Sign C and then into hexagonal {delta}-MoN by further increasing the temperature to 600 Degree-Sign C under a NH{sub 3} flow. The nitridation temperature employed here is much lower than that employed in nitridation of crystalline materials, and the amorphous materials underwent a unique nitridation process. Besides this, the bimetallic nitride Ni{sub 2}Mo{sub 3}N was also synthesized by nitridating amorphous bimetallic precursor. These results suggested that the nitridation of amorphous precursor possessed potential to be a general method for synthesizing many interstitial metallic compounds, such as nitrides and carbides at low temperature. - graphical abstract: Amorphous oxide was used as new precursor to prepare nitride at low temperature. Pure {gamma}-Mo{sub 2}N and {delta}-MoN were obtained at 400 Degree-Sign C and at 600 Degree-Sign C, respectively. Highlights: Black-Right-Pointing-Pointer We bring out a new method to synthesize transition metal nitrides at low temperature. Black-Right-Pointing-Pointer Both mono- and bimetallic molybdenum nitrides were synthesized at a mild condition. Black-Right-Pointing-Pointer The formation of two different molybdenum nitrides {gamma}-Mo{sub 2}N and {delta}-MoN can be controlled from the same metastable precursor. Black-Right-Pointing-Pointer The nitridation temperature was much lower than that reported from crystalline precursors. Black-Right-Pointing-Pointer The metastable precursor had different reaction process in comparison with crystalline precursor.

Wang, Huamin; Wu, Zijie; Kong, Jing [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China)] [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China); Wang, Zhiqiang, E-mail: zqwang@mail.nankai.edu.cn [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China) [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China); Tianjin Key Laboratory of Water Environment and Resources, Tianjin Normal University, No. 393 Binshui Road, Xiqing Dist., Tianjin 300387 (China); Zhang, Minghui, E-mail: zhangmh@nankai.edu.cn [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China)] [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China)

2012-10-15T23:59:59.000Z

80

Process for forming pure silver ohmic contacts to N- and P-type gallium arsenide materials  

DOE Patents (OSTI)

Disclosed is an improved process for manufacturing gallium arsenide semiconductor devices having as its components a n-type gallium arsenide substrate layer and a p-type gallium arsenide diffused layer. The improved process comprises forming a pure silver ohmic contact to both the diffuse layer and the substrate layer wherein the n-type layer comprises a substantially low doping carrier concentration.

Hogan, S.J.

1983-03-13T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Pure silver ohmic contacts to N- and P- type gallium arsenide materials  

DOE Patents (OSTI)

Disclosed is an improved process for manufacturing gallium arsenide semiconductor devices having as its components an n-type gallium arsenide substrate layer and a p-type gallium arsenide diffused layer. The improved process comprises forming a pure silver ohmic contact to both the diffused layer and the substrate layer, wherein the n-type layer comprises a substantially low doping carrier concentration.

Hogan, Stephen J. (Golden, CO)

1986-01-01T23:59:59.000Z

82

Dark energy from bulk matter  

SciTech Connect

We consider the possibility of getting accelerated expansion and w=-1 crossing in the context of a braneworld cosmological setup, endowed with a bulk energy-momentum tensor. For a given ansatz of the bulk content, we demonstrate that the bulk pressures dominate the dynamics at late times and can lead to accelerated expansion. We also analyze the constraints under which we can get a realistic profile for the effective equation of state and conclude that matter in the bulk has the effect of dark energy on the brane. Furthermore, we show that it is possible to simulate the behavior to a Chaplygin gas using nonexotic bulk matter.

Bogdanos, C.; Dimitriadis, A.; Tamvakis, K. [Physics Department, University of Ioannina, Ioannina GR451 10 (Greece)

2007-04-15T23:59:59.000Z

83

Effect of oxidation on the Mechanical Properties of Liquid Gallium and Eutectic Gallium-Indium  

E-Print Network (OSTI)

Liquid metals exhibit remarkable mechanical properties, in particular large surface tension and low viscosity. However, these properties are greatly affected by oxidation when exposed to air. We measure the viscosity, surface tension, and contact angle of gallium (Ga) and a eutectic gallium-indium alloy (eGaIn) while controlling such oxidation by surrounding the metal with an acid bath of variable concentration. Rheometry measurements reveal a yield stress directly attributable to an oxide skin that obscures the intrinsic behavior of the liquid metals. We demonstrate how the intrinsic viscosity can be obtained with precision through a scaling technique that collapses low- and high-Reynolds number data. Measuring surface tension with a pendant drop method, we show that the oxide skin generates a surface stress that mimics surface tension and develop a simple model to relate this to the yield stress obtained from rheometry. We find that yield stress, surface tension, and contact angle all transition from solid-like to liquid behavior at the same critical acid concentration, thereby quantitatively confirming that the wettability of these liquid metals is due to the oxide skin.

Qin Xu; Nikolai Qudalov; Qiti Guo; Heinrich Jaeger; Eric Brown

2012-01-23T23:59:59.000Z

84

Silicon nitride reinforced with molybdenum disilicide  

DOE Patents (OSTI)

Compositions of matter comprised of silicon nitride and molybdenum disilicide and methods of making the compositions, where the molybdenum disilicide is present in amounts ranging from about 5 to about 50 vol%.

Petrovic, J.J.; Honnell, R.E.

1990-12-31T23:59:59.000Z

85

Low temperature route to uranium nitride  

SciTech Connect

A method of preparing an actinide nitride fuel for nuclear reactors is provided. The method comprises the steps of a) providing at least one actinide oxide and optionally zirconium oxide; b) mixing the oxide with a source of hydrogen fluoride for a period of time and at a temperature sufficient to convert the oxide to a fluoride salt; c) heating the fluoride salt to remove water; d) heating the fluoride salt in a nitrogen atmosphere for a period of time and at a temperature sufficient to convert the fluorides to nitrides; and e) heating the nitrides under vacuum and/or inert atmosphere for a period of time sufficient to convert the nitrides to mononitrides.

Burrell, Anthony K. (Los Alamos, NM); Sattelberger, Alfred P. (Darien, IL); Yeamans, Charles (Berkeley, CA); Hartmann, Thomas (Idaho Falls, ID); Silva, G. W. Chinthaka (Las Vegas, NV); Cerefice, Gary (Henderson, NV); Czerwinski, Kenneth R. (Henderson, NV)

2009-09-01T23:59:59.000Z

86

Method of nitriding refractory metal articles  

DOE Patents (OSTI)

A method of nitriding a refractory-nitride forming metal or metalloid articles and composite articles. A consolidated metal or metalloid article or composite is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article or composite is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article or composite is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid or composite to an article or composite of refractory nitride. In addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Tiegs, Terry N. (Lenoir City, TN); Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Omatete, Ogbemi O. (Lagos, NG); Young, Albert C. (Flushing, NY)

1994-01-01T23:59:59.000Z

87

Method of nitriding refractory metal articles  

DOE Patents (OSTI)

A method of nitriding a refractory-nitride forming metal or metalloid articles and composite articles. A consolidated metal or metalloid article or composite is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article or composite is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article or composite is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid or composite to an article or composite of refractory nitride. In addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Tiegs, T.N.; Holcombe, C.E.; Dykes, N.L.; Omatete, O.O.; Young, A.C.

1994-03-15T23:59:59.000Z

88

Silicon nitride reinforced with molybdenum disilicide  

DOE Patents (OSTI)

Compositions of matter comprised of silicon nitride and molybdenum disilicide and methods of making the compositions, where the molybdenum disilicide is present in amounts ranging from about 5 to about 50 vol. %.

Petrovic, John J. (Los Alamos, NM); Honnell, Richard E. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

89

Creating bulk nanocrystalline metal.  

Science Conference Proceedings (OSTI)

Nanocrystalline and nanostructured materials offer unique microstructure-dependent properties that are superior to coarse-grained materials. These materials have been shown to have very high hardness, strength, and wear resistance. However, most current methods of producing nanostructured materials in weapons-relevant materials create powdered metal that must be consolidated into bulk form to be useful. Conventional consolidation methods are not appropriate due to the need to maintain the nanocrystalline structure. This research investigated new ways of creating nanocrystalline material, new methods of consolidating nanocrystalline material, and an analysis of these different methods of creation and consolidation to evaluate their applicability to mesoscale weapons applications where part features are often under 100 {micro}m wide and the material's microstructure must be very small to give homogeneous properties across the feature.

Fredenburg, D. Anthony (Georgia Institute of Technology, Atlanta, GA); Saldana, Christopher J. (Purdue University, West Lafayette, IN); Gill, David D.; Hall, Aaron Christopher; Roemer, Timothy John (Ktech Corporation, Albuquerque, NM); Vogler, Tracy John; Yang, Pin

2008-10-01T23:59:59.000Z

90

Method for improving the growth of cadmium telluride on a gallium arsenide substrate  

DOE Patents (OSTI)

A method for preparing a gallium arsenide substrate, prior to growing a layer of cadmium telluride on a support surface thereof. The preparation includes the steps of cleaning the gallium arsenide substrate and thereafter forming prepatterned shapes on the support surface of the gallium arsenide substrate. The layer of cadmium telluride then grown on the prepared substrate results in dislocation densities of approximately 1{times}10{sup 6}/cm{sup 2} or less. The prepatterned shapes on the support surface of the gallium arsenide substrate are formed by reactive ion etching an original outer surface of the gallium arsenide substrate and into the body of the gallium arsenide substrate to a depth of at least two microns. The prepatterned shapes have the appearance of cylindrical mesas each having a diameter of at lease twelve microns. After the mesas are formed on the support surface of the gallium arsenide substrate, the substrate is again cleaned.

Reno, J.L.

1990-12-31T23:59:59.000Z

91

A statistical analysis of the effect of PECVD deposition parameters on surface and bulk recombination in silicon solar cells  

DOE Green Energy (OSTI)

We have performed a statistically designed multiparameter experiment using response surface methodology to determine the optimum deposition and anneal conditions for PECVD silicon-oxide and silicon-nitride films on Si solar cells. Our process includes a unique in situ hydrogen plasma treatment to promote bulk defect passivation independently of surface effects. Our goal has been to define a process to optimize cell performance by minimizing recombination while also providing an effective antireflection coating. Our initial results show that excellent emitter-surface passivation, approaching that of the best thermally grown oxides, can be obtained using a single-layer nitride coating whose refractive index is optimized for antireflection purposes. Use of the PECVD-nitride instead of a TiO{sub 2} ARC resulted in an 11% increase in output power.

Ruby, D.S. [Sandia National Labs., Albuquerque, NM (United States); Wilbanks, W.L.; Fleddermann, C.B. [Univ. of New Mexico, Albuquerque, NM (United States)

1995-01-01T23:59:59.000Z

92

Hybrid silicon nanocrystal silicon nitride dynamic random access memory  

Science Conference Proceedings (OSTI)

This paper introduces a silicon nanocrystal-silicon nitride hybrid single transistor cell for potential dynamic RAM (DRAM) applications that stores charge in silicon nanocrystals or a silicon nitride charge trapping layer or both. The memory operates ...

R. F. Steimle; M. Sadd; R. Muralidhar; Rajesh Rao; B. Hradsky; S. Straub; B. E. White, Jr.

2003-12-01T23:59:59.000Z

93

Silicon nitride ceramic having high fatigue life and high toughness  

DOE Patents (OSTI)

A sintered silicon nitride ceramic comprising between about 0.6 mol % and about 3.2 mol % rare earth as rare earth oxide, and between about 85 w/o and about 95 w/o beta silicon nitride grains, wherein at least about 20% of the beta silicon nitride grains have a thickness of greater than about 1 micron.

Yeckley, Russell L. (Oakham, MA)

1996-01-01T23:59:59.000Z

94

Silicon-nitride and metal composite  

SciTech Connect

A composite and a method for bonding the composite. The composite includes a ceramic portion of silicon nitride, a refractory metal portion and a layer of MoSi.sub.2 indirectly bonding the composite together. The method includes contacting the layer of MoSi.sub.2 with a surface of the silicon nitride and with a surface of the metal; heating the layer to a temperature below 1400.degree. C.; and, simultaneously with the heating, compressing the layer such that the contacting is with a pressure of at least 30 MPa. This composite overcomes useful life problems in the fabrication of parts for a helical expander for use in power generation.

Landingham, Richard L. (Livermore, CA); Huffsmith, Sarah A. (Urbana, IL)

1981-01-01T23:59:59.000Z

95

III-Nitride Semiconductors for Photovoltaic Applications  

DOE Green Energy (OSTI)

Using a band-structure method that includes bandgap correction, we study the chemical trends of the bandgap variation in III-V semiconductors and predict that the bandgap for InN is 0.85 0.1 eV. This result suggests that InN and its III-nitride alloys are suitable for photovoltaic applications. The unusually small bandgap for InN is explained in terms of the atomic energies and the bandgap deformation potentials. The electronic and structural properties of the nitrides and their alloys are also provided.

Wei, S. H.

2003-05-01T23:59:59.000Z

96

Bulk Power Transmission Study  

E-Print Network (OSTI)

"Texans now have a choice. We can become more efficient and maintain our standard of living, or we can continue business as usual and watch our standard of living erode from competition from other regions. In the past, except for improving reliability, there was no need for a strong transmission system. When Texas generation was primarily gas fueled, the extensive natural gas pipeline network moved energy easily within the state. In recent years two things have changed: 1. Electric utilities have made extensive investment in lignite, coal, and nuclear plants and, 2. Improvements in gas turbine technology and the removal of institutional barriers has encouraged cogeneration at many of our energy intensive process industries. This energy diversity means that there are now significant differences in energy costs between units. The variable costs of generation of power can vary between units by a ratio of 2 or 3 to 1 and this difference will be accentuated when energy costs rise (and they will; it’s a question of when, not if). The potential for costs savings by optional dispatching of the entire interconnected system are greater than ever before as demonstrated by the PUC's Bulk Power Transmission Study. And the potential can be enhanced with added transmission system investment. Cogeneration and small power production has proven to be the most cost effective way for Texas to add additional generating capacity needed to supply an economy that is starting to rebound and to replace old, obsolete power plants. The freedom to locate these facilities at the fuel source or at the site of large thermal demand makes real economic and environmental sense. The use of renewable or waste fuels allows something that would otherwise be wasted to contribute to our economy. Fossil fuels that are displaced can be redirected to another use or consumed for future benefit. By integrating a gas turbine generator with a. process plant, the natural gas required for producing electricity can be reduced by 40% below that required for a combined cycle. The heat rejected from a gas turbine, combined cycle, or steam plant can be redirected to a process use that contributes to our economy by producing something of value to world markets. By contrast a conventional power plant is paid for by the rate payers and consumes Texas natural resources and therefore is a burden rather than an enhancement to our economy. The optimal location of facilities are possible only if there is an adequate transmission system. Utility, consumer and industry must cooperate to improve our transmission system for the benefit of all Texas. The Texas Public Utilities Commission has taken the lead in promoting efficiency by requiring transmission wheeling between qualifying facilities and electric utilities. Several cogeneration facilities have been constructed as a result. In order to encourage small power production, the rule needs to be expanded to include projects interconnected with distribution systems. Most renewable resource projects are relatively small and cannot afford the cost of a high voltage interconnect, and yet their characteristics match a baseload need. The ability to wheel power to a utility that needs base load power from a distribution level interconnection is essential to development of these smaller projects."

John, T.

1988-09-01T23:59:59.000Z

97

Using the genetic algorithm to design gallium indium nitride/gallium nitride light-emitting diodes with reduced efficiency droop and reduced spectral instability with respect to injection current  

Science Conference Proceedings (OSTI)

Today we are witnessing a fast growing trend that is redefining the concept of lighting. Numerous governments from all over the world have passed legislation to phase out incandescent light bulbs, with the objective of encouraging energy-efficient ...

Roya Mirhosseini / Partha S. Dutta

2010-01-01T23:59:59.000Z

98

Effects of asymmetry on electron spin dynamics in gallium arsenide quantum wells.  

E-Print Network (OSTI)

??This work presents optical studies of electron spin dynamics in gallium arsenide (GaAs) quantum wells, focusing on the effect of inversion asymmetric confinement potentials on… (more)

Eldridge, Peter Stephen

2009-01-01T23:59:59.000Z

99

bulk power | OpenEI  

Open Energy Info (EERE)

bulk power bulk power Dataset Summary Description The Form EIA-411, "Coordinated Bulk Power Supply Program Report," collects information from the Nation's power system planners about the electricity supply, both capacity and energy, that is needed to serve current demand and for future growth. Source Energy Information Administration (EIA) Date Released December 03rd, 2010 (3 years ago) Date Updated December 03rd, 2010 (3 years ago) Keywords bulk power EIA Electricity Generation Data application/vnd.ms-excel icon Net Energy for Load - Historic, Actual and Projected Five-Years (xls, 26.1 KiB) application/vnd.ms-excel icon Noncoincident Peak Load - Historic, Actual and Projected Five-Years (xls, 25.6 KiB) application/vnd.ms-excel icon Noncoincident Peak Load - Historic, Actual and Projected Five-Years (xls, 0 bytes)

100

High-Efficiency Nitride-Based Solid-State Lighting  

SciTech Connect

In this final technical progress report we summarize research accomplished during Department of Energy contract DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. Two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and the Lighting Research Center at Rensselaer Polytechnic Institute (led by Dr. N. Narendran), pursued the goals of this contract from thin film growth, characterization, and packaging/luminaire design standpoints. The UCSB team initially pursued the development of blue gallium nitride (GaN)-based vertical-cavity surface-emitting lasers, as well as ultraviolet GaN-based light emitting diodes (LEDs). In Year 2, the emphasis shifted to resonant-cavity light emitting diodes, also known as micro-cavity LEDs when extremely thin device cavities are fabricated. These devices have very directional emission and higher light extraction efficiency than conventional LEDs. Via the optimization of thin-film growth and refinement of device processing, we decreased the total cavity thickness to less than 1 {micro}m, such that micro-cavity effects were clearly observed and a light extraction efficiency of over 10% was reached. We also began the development of photonic crystals for increased light extraction, in particular for so-called ''guided modes'' which would otherwise propagate laterally in the device and be re-absorbed. Finally, we pursued the growth of smooth, high-quality nonpolar a-plane and m-plane GaN films, as well as blue light emitting diodes on these novel films. Initial nonpolar LEDs showed the expected behavior of negligible peak wavelength shift with increasing drive current. M-plane LEDs in particular show promise, as unpackaged devices had unsaturated optical output power of {approx} 3 mW at 200 mA drive current. The LRC's tasks were aimed at developing the subcomponents necessary for packaging UCSB's light emitting diodes, and packaging them to produce a white light fixture. During the third and final year of the project, the LRC team investigated alternate packaging methods for the white LED device to achieve at least 25 percent more luminous efficacy than traditional white LEDs; conducted optical ray-tracing analyses and human factors studies to determine the best form factor for the white light source under development, in terms of high luminous efficacy and greater acceptance by subjects; and developed a new die encapsulant using silicone-epoxy resins that showed less yellowing and slower degradation. At the conclusion of this project, the LRC demonstrated a new packaging method, called scattered photon extraction (SPE), that produced an average luminous flux and corresponding average efficacy of 90.7 lm and 36.3 lm/W, respectively, compared with 56.5 lm and 22.6 lm/W for a similar commercial white LED package. At low currents, the SPE package emitted white light with an efficacy of over 80 lm/W and had chromaticity values very close to the blackbody locus. The SPE package showed an overall improvement of 61% for this particular comparison, exceeding the LRC's third-year goal of 25% improvement.

Paul T. Fini; Shuji Nakamura

2005-07-30T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Anisotropic Hexagonal Boron Nitride Nanomaterials - Synthesis and Applications  

SciTech Connect

Boron nitride (BN) is a synthetic binary compound located between III and V group elements in the Periodic Table. However, its properties, in terms of polymorphism and mechanical characteristics, are rather close to those of carbon compared with other III-V compounds, such as gallium nitride. BN crystallizes into a layered or a tetrahedrally linked structure, like those of graphite and diamond, respectively, depending on the conditions of its preparation, especially the pressure applied. Such correspondence between BN and carbon readily can be understood from their isoelectronic structures [1, 2]. On the other hand, in contrast to graphite, layered BN is transparent and is an insulator. This material has attracted great interest because, similar to carbon, it exists in various polymorphic forms exhibiting very different properties; however, these forms do not correspond strictly to those of carbon. Crystallographically, BN is classified into four polymorphic forms: Hexagonal BN (h-BN) (Figure 1(b)); rhombohedral BN (r-BN); cubic BN (c-BN); and wurtzite BN (w-BN). BN does not occur in nature. In 1842, Balmain [3] obtained BN as a reaction product between molten boric oxide and potassium cyanide under atmospheric pressure. Thereafter, many methods for its synthesis were reported. h-BN and r-BN are formed under ambient pressure. c-BN is synthesized from h-BN under high pressure at high temperature while w-BN is prepared from h-BN under high pressure at room temperature [1]. Each BN layer consists of stacks of hexagonal plate-like units of boron and nitrogen atoms linked by SP{sup 2} hybridized orbits and held together mainly by Van der Waals force (Fig 1(b)). The hexagonal polymorph has two-layered repeating units: AA'AA'... that differ from those in graphite: ABAB... (Figure 1(a)). Within the layers of h-BN there is coincidence between the same phases of the hexagons, although the boron atoms and nitrogen atoms are alternatively located along the c-axis. The rhombohedral system consists of three-layered units: ABCABC..., whose honeycomb layers are arranged in a shifted phase, like as those of graphite. Reflecting its weak interlayer bond, the h-BN can be cleaved easily along its layers, and hence, is widely used as a lubricant material. The material is stable up to a high temperature of 2300 C before decomposition sets in [2] does not fuse a nitrogen atmosphere of 1 atm, and thus, is applicable as a refractory material. Besides having such properties, similar to those of graphite, the material is transparent, and acts as a good electric insulator, especially at high temperatures (10{sup 6} {Omega}m at 1000 C) [1]. c-BN and w-BN are tetrahedrally linked BN. The former has a cubic sphalerite-type structure, and the latter has a hexagonal wurtzite-type structure. c-BN is the second hardest known material (the hardest is diamond), the so-called white diamond. It is used mainly for grinding and cutting industrial ferrous materials because it does not react with molten iron, nickel, and related alloys at high temperatures whereas diamond does [1]. It displays the second highest thermal conductivity (6-9 W/cm.deg) after diamond. This chapter focuses principally upon information about h-BN nanomaterials, mainly BN nanotubes (BNNTs), porous BN, mono- and few-layer-BN sheets. There are good reviews book chapters about c-BN in [1, 4-6].

Han,W.Q.

2008-08-01T23:59:59.000Z

102

Preparation Of Copper Indium Gallium Diselenide Films For Solar Cells  

DOE Patents (OSTI)

High quality thin films of copper-indium-gallium-diselenide useful in the production of solar cells are prepared by electrodepositing at least one of the constituent metals onto a glass/Mo substrate, followed by physical vapor deposition of copper and selenium or indium and selenium to adjust the final stoichiometry of the thin film to approximately Cu(In,Ga)Se.sub.2. Using an AC voltage of 1-100 KHz in combination with a DC voltage for electrodeposition improves the morphology and growth rate of the deposited thin film. An electrodeposition solution comprising at least in part an organic solvent may be used in conjunction with an increased cathodic potential to increase the gallium content of the electrodeposited thin film.

Bhattacharya, Raghu N. (Littleton, CO); Contreras, Miguel A. (Golden, CO); Keane, James (Lakewood, CO); Tennant, Andrew L. (Denver, CO), Tuttle, John R. (Denver, CO); Ramanathan, Kannan (Lakewood, CO); Noufi, Rommel (Golden, CO)

1998-08-08T23:59:59.000Z

103

Titanium nitride electrodes for thermoelectric generators  

DOE Patents (OSTI)

The invention is directed to a composite article suitable for use in thermoelectric generators. The article comprises a thin film of titanium nitride as an electrode deposited onto solid electrolyte. The invention is also directed to the method of making same.

Novak, Robert F. (Farmington Hills, MI); Schmatz, Duane J. (Dearborn Heights, MI); Hunt, Thomas K. (Ann Arbor, MI)

1987-12-22T23:59:59.000Z

104

Silicon nitride having a high tensile strength  

DOE Patents (OSTI)

A silicon nitride ceramic comprising: a) inclusions no greater than 25 microns in length, b) agglomerates no greater than 20 microns in diameter, and c) a surface finish of less than about 8 microinches, said ceramic having a four-point flexural strength of at least about 900 MPa.

Pujari, Vimal K. (Northboro, MA); Tracey, Dennis M. (Medfield, MA); Foley, Michael R. (Oxford, MA); Paille, Norman I. (Oxford, MA); Pelletier, Paul J. (Millbury, MA); Sales, Lenny C. (Grafton, MA); Willkens, Craig A. (Sterling, MA); Yeckley, Russell L. (Oakham, MA)

1996-01-01T23:59:59.000Z

105

DESIGN AND ANALYSIS OF AN INTEGRATED PULSE MODULATED S-BAND POWER AMPLIFIER IN GALLIUM NITRIDE PROCESS  

SciTech Connect

The design of power amplifiers in any semi-conductor process is not a trivia exercise and it is often encountered that the simulated solution is qualitatively different than the results obtained. Phenomena such as oscillation occurring either in-band or out of band and sometimes at subharmonic intervals, continuous spectrum noticed in some frequency bands, often referred to as chaos, and jumps and hysteresis effects can all be encountered and render a design useless. All of these problems might have been identified through a more rigorous approach to stability analysis. Designing for stability is probably the one area of amplifier design that receives the least amount of attention but incurs the most catastrophic of effects if it is not performed properly. Other parameters such as gain, power output, frequency response and even matching may suitable mitigation paths. But the lack of stability in an amplifier has no mitigating path. In addition to of loss of the design completely there are the increased production cycle costs, costs involved with investigating and resolving the problem and the costs involved with schedule slips or delays resulting from it. The Linville or Rollett stability criteria that many microwave engineers follow and rely exclusively on is not sufficient by itself to ensure a stable and robust design. It will be shown that the universal belief that unconditional stability is obtained through an analysis of the scattering matrix S to determine if 1 and |{Delta}{sub S}| < 1 is only part of the procedure and other tools must be used to validate the criteria. The research shown contributes to the state of the art by developing a more thorough stability design technique for designing amplifiers of any class, whether that be current mode or switch mode, than is currently undertaken with the goal of obtaining first pass design success.

STEVE SEDLOCK

2012-04-04T23:59:59.000Z

106

Comparative band alignment of plasma-enhanced atomic layer deposited high-k dielectrics on gallium nitride  

SciTech Connect

Al{sub 2}O{sub 3} films, HfO{sub 2} films, and HfO{sub 2}/Al{sub 2}O{sub 3} stacked structures were deposited on n-type, Ga-face, GaN wafers using plasma-enhanced atomic layer deposition (PEALD). The wafers were first treated with a wet-chemical clean to remove organics and an in-situ combined H{sub 2}/N{sub 2} plasma at 650 Degree-Sign C to remove residual carbon contamination, resulting in a clean, oxygen-terminated surface. This cleaning process produced slightly upward band bending of 0.1 eV. Additional 650 Degree-Sign C annealing after plasma cleaning increased the upward band bending by 0.2 eV. After the initial clean, high-k oxide films were deposited using oxygen PEALD at 140 Degree-Sign C. The valence band and conduction band offsets (VBOs and CBOs) of the Al{sub 2}O{sub 3}/GaN and HfO{sub 2}/GaN structures were deduced from in-situ x-ray and ultraviolet photoemission spectroscopy (XPS and UPS). The valence band offsets were determined to be 1.8 and 1.4 eV, while the deduced conduction band offsets were 1.3 and 1.0 eV, respectively. These values are compared with the theoretical calculations based on the electron affinity model and charge neutrality level model. Moreover, subsequent annealing had little effect on these offsets; however, the GaN band bending did change depending on the annealing and processing. An Al{sub 2}O{sub 3} layer was investigated as an interfacial passivation layer (IPL), which, as results suggest, may lead to improved stability, performance, and reliability of HfO{sub 2}/IPL/GaN structures. The VBOs were {approx}0.1 and 1.3 eV, while the deduced CBOs were 0.6 and 1.1 eV for HfO{sub 2} with respect to Al{sub 2}O{sub 3} and GaN, respectively.

Yang Jialing; Eller, Brianna S.; Zhu Chiyu; England, Chris; Nemanich, Robert J. [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States)

2012-09-01T23:59:59.000Z

107

Appraisal of lupus nephritis by renal imaging with gallium-67  

Science Conference Proceedings (OSTI)

To assess the activity of lupus nephritis, 43 patients with systemic lupus erythematosus (SLE) were studied by gallium imaging. Delayed renal visualization 48 hours after the gallium injection, a positive result, was noted in 25 of 48 scans. Active renal disease was defined by the presence of hematuria, pyuria (10 or more red blood cells or white blood cells per high-power field), proteinuria (1 g or more per 24 hours), a rising serum creatinine level, or a recent biopsy specimen showing proliferative and/or necrotizing lesions involving more than 20 percent of glomeruli. Renal disease was active in 18 instances, inactive in 23, and undetermined in seven (a total of 48 scans). Sixteen of the 18 scans (89 percent) in patients with active renal disease showed positive findings, as compared with only four of 23 scans (17 percent) in patients with inactive renal disease (p less than 0.001). Patients with positive scanning results had a higher rate of hypertension (p = 0.02), nephrotic proteinuria (p = 0.01), and progressive renal failure (p = 0.02). Mild mesangial nephritis (World Health Organization classes I and II) was noted only in the patients with negative scanning results (p = 0.02) who, however, showed a higher incidence of severe extrarenal SLE (p = 0.04). It is concluded that gallium imaging is a useful tool in evaluating the activity of lupus nephritis.

Bakir, A.A.; Lopez-Majano, V.; Hryhorczuk, D.O.; Rhee, H.L.; Dunea, G.

1985-08-01T23:59:59.000Z

108

Robbins Corn & Bulk Services | Open Energy Information  

Open Energy Info (EERE)

Robbins Corn & Bulk Services Jump to: navigation, search Name Robbins Corn & Bulk Services Place Sackets Harbor, NY Information About Partnership with NREL Partnership with NREL...

109

Characteristics of graphene FET directly transformed from a resist pattern through interfacial graphitization of liquid gallium  

Science Conference Proceedings (OSTI)

We found that an extremely thin resist pattern on silicon dioxide can be directly transformed into a graphene field effect transistor (FET) channel via interfacial graphitization of liquid gallium. These patterned graphene FETs have p-type characteristics ... Keywords: Conductance, FET, Gallium, Graphene, Graphitization, Resist, Solid phase reaction

Jun-ichi Fujita; Ryuichi Ueki; Takuya Nishijima; Yosuke Miyazawa

2011-08-01T23:59:59.000Z

110

IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 2, APRIL 2012 123 Gallium Arsenide Solar Cell Absorption  

E-Print Network (OSTI)

IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 2, APRIL 2012 123 Gallium Arsenide Solar Cell Absorption flat gallium arsenide solar cell, we show that it is possible to modify the flow of light and enhance above the solar cell. The incoupling element is lossless and, thus, has the advantage that no energy

Grandidier, Jonathan

111

Grain Size Effects on the Mechanical Properties of Bulk Structural ...  

Science Conference Proceedings (OSTI)

Unconventional Short-Term Glow Discharge Nitriding of 316l Austenitic Steel · Using Accumulative Roll Bonding to Process Ultrafine Grained ...

112

Measurement of achievable plutonium decontamination from gallium by means of PUREX solvent extraction  

SciTech Connect

The objective of the work described herein was to measure, experimentally, the achievable decontamination of plutonium from gallium by means of the PUREX solvent extraction process. Gallium is present in surplus weapons-grade plutonium (WG-Pu) at a concentration of approximately 1 wt%. Plans are to dispose of surplus WG-Pu by converting it to UO{sub 2}-PuO{sub 2} mixed oxide (MOX) fuel and irradiating it in commercial power reactors. However, the presence of high concentrations of gallium in plutonium is a potential corrosion problem during the process of MOX fuel irradiation. The batch experiments performed in this study were designed to measure the capability of the PUREX solvent extraction process to separate gallium from plutonium under idealized conditions. Radioactive tracing of the gallium with {sup 72}Ga enabled the accurate measurement of low concentrations of extractable gallium. The experiments approximated the proposed flowsheet for WG-Pu purification, except that only one stage was used for each process: extraction, scrubbing, and stripping. With realistic multistage countercurrent systems, much more efficient separations are generally obtained. The gallium decontamination factor (DF) obtained after one extraction stage was about 3 x 10{sup 6}. After one scrub stage, all gallium measurements were less than the detection limit, which corresponded to DFs >5 x 10{sup 6}. All these values exceed a 10{sup 6} DF needed to meet a hypothetical 10-ppb gallium impurity limit in MOX fuel. The results of this study showed no inherent or fundamental problem with regard to removing gallium from plutonium.

Collins, E.D.; Campbell, D.O.; Felker, L.K.

2000-01-01T23:59:59.000Z

113

Available Technologies: Boron Nitride Nanotubes with Modified Surfaces  

Nano- & Micro-technology; Software and IT ; Licensing Interest Form Receive Customized Tech Alerts. Boron Nitride Nanotubes with Modified Surfaces . IB-2331 and IB-2332 .

114

Method for locating metallic nitride inclusions in metallic alloy ingots  

DOE Patents (OSTI)

A method of determining the location and history of metallic nitride and/or oxynitride inclusions in metallic melts. The method includes the steps of labeling metallic nitride and/or oxynitride inclusions by making a coreduced metallic-hafnium sponge from a mixture of hafnium chloride and the chloride of a metal, reducing the mixed chlorides with magnesium, nitriding the hafnium-labeled metallic-hafnium sponge, and seeding the sponge to be melted with hafnium-labeled nitride inclusions. The ingots are neutron activated and the hafnium is located by radiometric means. Hafnium possesses exactly the proper metallurgical and radiochemical properties for this use.

White, Jack C. (Albany, OR); Traut, Davis E. (Corvallis, OR); Oden, Laurance L. (Albany, OR); Schmitt, Roman A. (Corvallis, OR)

1992-01-01T23:59:59.000Z

115

Processing of Optically Translucent/Transparent Nitrides from ...  

Science Conference Proceedings (OSTI)

With the aim coupling good thermal conductivity with optical light transmission and emission, aluminum nitride with rare earth dopants (Gd2O3, Gd ,Dy etc.) ...

116

Bulk Hauling Equipment for CHG  

NLE Websites -- All DOE Office Websites (Extended Search)

BULK HAULING EQUIPMENT FOR CHG BULK HAULING EQUIPMENT FOR CHG Don Baldwin Director of Product Development - Hexagon Lincoln HEXAGON LINCOLN TITAN(tm) Module System Compressed Hydrogen Gas * Capacity 250 bar - 616 kg 350 bar - 809 kg 540 bar - 1155 kg * Gross Vehicle Weight (with prime mover) 250 bar - 28 450 kg 350 bar - 30 820 kg 540 bar - 39 440 kg * Purchase Cost 250 bar - $510,000 350 bar - $633,750 540 bar - $1,100,000 Compressed Natural Gas * Capacity (250 bar at 15 C) - 7412 kg * GVW (With prime mover) - 35 250 kg * Purchase Cost (+/- 5%) - $510,000 HEXAGON LINCOLN TITAN(tm) V Magnum Trailer System Compressed Hydrogen Gas * Capacity 250 bar - 800 kg 350 bar - 1050 kg 540 bar - 1500 kg * Gross Vehicle Weight (with prime mover) 250 bar - 31 000 kg 350 bar - 34 200 kg 540 bar - 45 700 kg * Purchase Cost (+/-

117

Nitriding of super alloys for enhancing physical properties  

DOE Patents (OSTI)

The invention teaches the improvement of certain super alloys by exposing the alloy to an atmosphere of elemental nitrogen at elevated temperatures in excess of 750/sup 0/C but less than 1150/sup 0/C for an extended duration, viz., by nitriding the surface of the alloy, to establish barrier nitrides of the order of 25 to 100 micrometers thickness. These barrier

Purohit, A.

1984-06-25T23:59:59.000Z

118

III-Nitride LEDs with photonic crystal structures.  

SciTech Connect

Electrical operation of III-Nitride light emitting diodes (LEDs) with photonic crystal structures is demonstrated. Employing photonic crystal structures in III-Nitride LEDs is a method to increase light extraction efficiency and directionality. The photonic crystal is a triangular lattice formed by dry etching into the III-Nitride LED. A range of lattice constants is considered (a {approx} 270-340nm). The III-Nitride LED layers include a tunnel junction providing good lateral current spreading without a semi-absorbing metal current spreader as is typically done in conventional III-Nitride LEDs. These photonic crystal III-Nitride LED structures are unique because they allow for carrier recombination and light generation proximal to the photonic crystal (light extraction area) yet displaced from the absorbing metal contact. The photonic crystal Bragg scatters what would have otherwise been guided modes out of the LED, increasing the extraction efficiency. The far-field light radiation patterns are heavily modified compared to the typical III-Nitride LED's Lambertian output. The photonic crystal affects the light propagation out of the LED surface, and the radiation pattern changes with lattice size. LEDs with photonic crystals are compared to similar III-Nitride LEDs without the photonic crystal in terms of extraction, directionality, and emission spectra.

Wendt, Joel Robert; Sigalas, M. M. (Agilent Technologies, Palo Alto, CA); Epler, J. E. (Lumileds Lighting, San Jose, CA); Krames, M. R. (Lumileds Lighting, San Jose, CA); Li, D. (University of New Mexico, Albuquerque NM); Brueck, Stephen R. J. (University of New Mexico, Albuquerque NM); Shagam, M. (Boston University, Boston, MA); Gardner, N. F. (Lumileds Lighting, San Jose, CA); Wierer, Jonathan J. (Lumileds Lighting, San Jose, CA)

2005-02-01T23:59:59.000Z

119

Molybdenum enhanced low-temperature deposition of crystalline silicon nitride  

DOE Patents (OSTI)

A process for chemical vapor deposition of crystalline silicon nitride which comprises the steps of: introducing a mixture of a silicon source, a molybdenum source, a nitrogen source, and a hydrogen source into a vessel containing a suitable substrate; and thermally decomposing the mixture to deposit onto the substrate a coating comprising crystalline silicon nitride containing a dispersion of molybdenum silicide.

Lowden, Richard A. (Powell, TN)

1994-01-01T23:59:59.000Z

120

Oxidation Protection of Uranium Nitride Fuel using Liquid Phase Sintering  

SciTech Connect

Two methods are proposed to increase the oxidation resistance of uranium nitride (UN) nuclear fuel. These paths are: (1) Addition of USi{sub x} (e.g. U3Si2) to UN nitride powder, followed by liquid phase sintering, and (2) 'alloying' UN nitride with various compounds (followed by densification via Spark Plasma Sintering or Liquid Phase Sintering) that will greatly increase oxidation resistance. The advantages (high thermal conductivity, very high melting point, and high density) of nitride fuel have long been recognized. The sodium cooled BR-10 reactor in Russia operated for 18 years on uranium nitride fuel (UN was used as the driver fuel for two core loads). However, the potential advantages (large power up-grade, increased cycle lengths, possible high burn-ups) as a Light Water Reactor (LWR) fuel are offset by uranium nitride's extremely low oxidation resistance (UN powders oxidize in air and UN pellets decompose in hot water). Innovative research is proposed to solve this problem and thereby provide an accident tolerant LWR fuel that would resist water leaks and high temperature steam oxidation/spalling during an accident. It is proposed that we investigate two methods to increase the oxidation resistance of UN: (1) Addition of USi{sub x} (e.g. U{sub 3}Si{sub 2}) to UN nitride powder, followed by liquid phase sintering, and (2) 'alloying' UN nitride with compounds (followed by densification via Spark Plasma Sintering) that will greatly increase oxidation resistance.

Dr. Paul A. Lessing

2012-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Process for producing ceramic nitrides anc carbonitrides and their precursors  

DOE Patents (OSTI)

A process for preparing ceramic nitrides and carbon nitrides in the form of very pure, fine particulate powder. Appropriate precursors is prepared by reaching a transition metal alkylamide with ammonia to produce a mixture of metal amide and metal imide in the form of an easily pyrolyzable precipitate.

Brown, G.M.; Maya, L.

1987-02-25T23:59:59.000Z

122

Gallium phosphide high-temperature bipolar junction transistor  

DOE Green Energy (OSTI)

Preliminary results are reported on the development of a high-temperature (> 350/sup 0/C) gallium phosphide bipolar junction transistor (BJT) for goethermal and other energy applications. This four-layer p/sup +/n/sup -/pp/sup +/ structure was fromed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into the lightly doped base. By appropriate choice of electrodes, the device may also be driven as an n-channel junction field-effect transistor. The gallium phosphide BJT is observed to have a common-emitter current gain peaking in the range of 6 to 10 (for temperatures from 20/sup 0/C to 400/sup 0/C) and a room-temperature, punchthrough-limited, collector-emitter breakdown voltage of approximately -6V. Other parameters of interest include an f/sub/ = 400 KHz (at 20/sup 0/C) and a collector base leakage current = 200 ..mu..A (at 350/sup 0/C).

Zipperian, T.E.; Dawson, L.R.; Caffin, R.J.

1981-03-01T23:59:59.000Z

123

Microsoft PowerPoint - Gallium Oxide_Ramana  

NLE Websites -- All DOE Office Websites (Extended Search)

Gallium Oxide Nanostructures Gallium Oxide Nanostructures for High Temperature Sensors C.V. Ramana (PI) Evgeny Shafirovich (Co-PI) Mechanical Engineering, University of Texas at El Paso Students: Ernesto Rubio (PhD); S.K. Samala (MS) A.K. Narayana Swamy (PhD); K. Abhilash (MS) Program Manager: Richard Dunst, NETL, DOE Project: DE-FE0007225 Project Period: 10/01/2011 to 09/31/2014 1 06/12/2013 DOE UCR/HBCU Conference, June 11-13, 2013 2 ď‚· Introduction ď‚· Research Objectives ď‚· Experiments â–ş Synthesis â–ş Characterization ď‚· Results and Discussion â–ş Pure Ga 2 O 3 Thin Films â–ş W-doped Ga 2 O 3 Thin Films (Physical Methods) ď‚· Summary & Future Work 06/12/2013 DOE UCR/HBCU Conference, June 11-13, 2013 3 06/12/2013 DOE UCR/HBCU Conference, June 11-13, 2013 4 Energy Systems High-T High-T High-P High-P

124

Markovian bulk-arrival and bulk-service queues with state-dependent control  

Science Conference Proceedings (OSTI)

We study a modified Markovian bulk-arrival and bulk-service queue incorporating state-dependent control. The stopped bulk-arrival and bulk-service queue is first investigated and the relationship with our queueing model is examined and exploited. Equilibrium ... Keywords: 60J27, 60J80, Bulk-arrival and bulk-service queues, Busy period distributions, Equilibrium distribution, Hitting times, Queue length distributions, State-dependent control, Transient behaviour

Anyue Chen; Phil Pollett; Junping Li; Hanjun Zhang

2010-03-01T23:59:59.000Z

125

Titanium nitride thin films for minimizing multipactoring  

DOE Patents (OSTI)

Applying a thin film coating to the surface of a workpiece, in particular, applying a coating of titanium nitride to a klystron window by means of a crossed-field diode sputtering array. The array is comprised of a cohesive group of numerous small hollow electrically conducting cylinders and is mounted so that the open ends of the cylinders on one side of the group are adjacent a titanium cathode plate. The workpiece is mounted so as to face the open ends of the other side of the group. A magnetic field is applied to the array so as to be coaxial with the cylinders and a potential is applied across the cylinders and the cathode plate, the cylinders as an anode being positive with respect to the cathode plate. The cylinders, the cathode plate and the workpiece are situated in an atmosphere of nitrogen which becomes ionized such as by field emission because of the electric field between the cylinders and cathode plate, thereby establishing an anode-cathode discharge that results in sputtering of the titanium plate. The sputtered titanium coats the workpiece and chemically combines with the nitrogen to form a titanium nitride coating on the workpiece. Gas pressure, gas mixtures, cathode material composition, voltages applied to the cathode and anode, the magnetic field, cathode, anode and workpiece spacing, and the aspect ratio (ratio of length to inner diameter) of the anode cylinders, all may be controlled to provide consistent optimum thin film coatings of various compositions and thicknesses. Another facet of the disclosure is the coating of microwave components per se with titanium nitride to reduce multipactoring under operating conditions of the components.

Welch, Kimo M. (Mountain View, CA)

1979-01-01T23:59:59.000Z

126

Hard and low friction nitride coatings and methods for forming the same  

DOE Patents (OSTI)

An improved coating material possessing super-hard and low friction properties and a method for forming the same. The improved coating material includes the use of a noble metal or soft metal homogeneously distributed within a hard nitride material. The addition of small amounts of such metals into nitrides such as molybdenum nitride, titanium nitride, and chromium nitride results in as much as increasing of the hardness of the material as well as decreasing the friction coefficient and increasing the oxidation resistance.

Erdemir, Ali (Naperville, IL); Urgen, Mustafa (Istanbul, TR); Cakir, Ali Fuat (Istanbul, TR); Eryilmaz, Osman Levent (Bolingbrook, IL); Kazmanli, Kursat (Istanbul, TR); Keles, Ozgul (Istanbul, TR)

2007-05-01T23:59:59.000Z

127

Limits on nu_e and anti-nu_e disappearance from Gallium and reactor experiments  

E-Print Network (OSTI)

The deficit observed in the Gallium radioactive source experiments is interpreted as a possible indication of the disappearance of electron neutrinos. In the effective framework of two-neutrino mixing we obtain $\\sin^{2}2\\vartheta \\gtrsim 0.03$ and $\\Delta{m}^{2} \\gtrsim 0.1 \\text{eV}^{2}$. The compatibility of this result with the data of the Bugey and Chooz reactor short-baseline antineutrino disappearance experiments is studied. It is found that the Bugey data present a hint of neutrino oscillations with $0.02 \\lesssim \\sin^{2}2\\vartheta \\lesssim 0.08$ and $\\Delta{m}^{2} \\approx 1.8 \\text{eV}^{2}$, which is compatible with the Gallium allowed region of the mixing parameters. This hint persists in the combined analyses of Bugey and Chooz data, of Gallium and Bugey data, and of Gallium, Bugey, and Chooz data.

Mario A. Acero; Carlo Giunti; Marco Laveder

2007-11-27T23:59:59.000Z

128

Polycrystalline Thin-Film Research: Copper Indium Gallium Diselenide (Fact Sheet)  

DOE Green Energy (OSTI)

Capabilities fact sheet for the National Center for Photovoltaics: Polycrystalline Thin-Film Research: Copper Indium Gallium Diselenide that includes scope, core competencies and capabilities, and contact/web information.

Not Available

2011-06-01T23:59:59.000Z

129

The radiation bio-effects of gallum-72 on leukemic cells via a gallium-transferrin complex  

E-Print Network (OSTI)

Improved methods for treatment of leukemia would be advantageous for patients and the medical community. This thesis reports results of a study of the cytotoxicity of radiolabeled transferrin in cultured leukemic cells. K-562 cells, from an erythroleukemic cell line, were grown and growth curves were plotted for characterization. K-562 cells grew logarithmically from approximately 250,000 cells mL?ą to 700,000 cells mL?ą and display a doubling time of approximately 20-21 hours. K-562 cells were exposed to x rays at an absorbed dose of 0, 1, 2, and 4 gray. Growth curves were plotted to create a dose response curve. Percent-cell survival in this experiment, and all subsequent experiments, was determined based on the extrapolation of the growth curves to time zero, as compared to a control. An absorbed dose of 1, 2, and 4 gray corresponded to a survival of 77([]14)%, 45([]7.4)% and 20([]2.4)%, respectively. This cell line is relatively resistant to radiation. K-562 cells were exposed to a radioactive gallium-72/stable gallium nitrate mixture to determine the effect gallium-72 decay has on cell survival . Simultaneously, K-562 cells were exposed to a concentration of stable gallium nitrate equivalent to the total gallium concentration, radioactive and stable, of the gallium-72/stable gallium mixture. This allowed a comparison of radioactive and chemotoxic effects due to gallium-72 and stable gallium, respectively. Exposures to gallium-72, at an activity of 184.0 kBq mL?ą, and stable gallium nitrate, at a concentration of 116.7 []M, resulted in a cell survival of 61([]10.5)% and 75([]12. 1)%, respectively. The difference is small when error is taken into consideration. Therefore radioactivity had little effect on cell survival at a specific activity of 6.3 MBq mg?ą. To properly assess the cytotoxicity of gallium-72 the specific activity must be increased. To determine the effect of ape-transferrin on the cytotoxicity of gallium nitrate, K-562 cells were exposed to stable gallium nitrate and increasing amounts of apo-transferrin. Cells exposed to 115.0 []M gallium nitrate exhibited an 82([]8.8)% cell survival compared to 54([]6.9)% following exposure to 115.0 []M gallium nitrate and 3.75 []M apo-transferrin. Apo-transferrin presumably increases cellular uptake of gallium nitrate thereby increasing its cyctotoxic effects.

Forbes, Christen Douglas

1999-01-01T23:59:59.000Z

130

Cordierite silicon nitride filters. Final report  

SciTech Connect

The objective of this project was to develop a silicon nitride based crossflow filter. This report summarizes the findings and results of the project. The project was phased with Phase I consisting of filter material development and crossflow filter design. Phase II involved filter manufacturing, filter testing under simulated conditions and reporting the results. In Phase I, Cordierite Silicon Nitride (CSN) was developed and tested for permeability and strength. Target values for each of these parameters were established early in the program. The values were met by the material development effort in Phase I. The crossflow filter design effort proceeded by developing a macroscopic design based on required surface area and estimated stresses. Then the thermal and pressure stresses were estimated using finite element analysis. In Phase II of this program, the filter manufacturing technique was developed, and the manufactured filters were tested. The technique developed involved press-bonding extruded tiles to form a filter, producing a monolithic filter after sintering. Filters manufactured using this technique were tested at Acurex and at the Westinghouse Science and Technology Center. The filters did not delaminate during testing and operated and high collection efficiency and good cleanability. Further development in areas of sintering and filter design is recommended.

Sawyer, J.; Buchan, B. [Acurex Environmental Corp., Mountain View, CA (United States); Duiven, R.; Berger, M. [Aerotherm Corp., Mountain View, CA (United States); Cleveland, J.; Ferri, J. [GTE Products Corp., Towanda, PA (United States)

1992-02-01T23:59:59.000Z

131

High-Temperature Decomposition of Brřnsted Acid Sites in Gallium-Substituted Zeolites  

SciTech Connect

The dehydroxylation of Broensted acid sites (BAS) in Ga-substituted zeolites was investigated at temperatures up to 850 C using X-ray absorption spectroscopy (XAS), Fourier transform infrared spectroscopy (FTIR), and mass spectrometry-temperature programmed desorption (MS-TPD). X-ray absorption near-edge spectroscopy (XANES) revealed that the majority of gallium has tetrahedral coordination even after complete dehydroxylation. The interatomic gallium-oxygen distance and gallium coordination number determined by extended X-ray absorption fine structure (EXAFS) are consistent with gallium in tetrahedral coordination at low T (< 550 C). Upon heating Ga-Beta and Ga-ZSM5 to 850 C, analysis of the EXAFS showed that 70 and 80% of the gallium was still in tetrahedral coordination. The remainder of the gallium was found to be in octahedral coordination. No trigonal Ga atoms were observed. FTIR measurements carried out at similar temperatures show that the intensity of the OH vibration due to BAS has been eliminated. MS-TPD revealed that hydrogen in addition to water evolved from the samples during dehydroxylation. This shows that dehydrogenation in addition to dehydration is a mechanism that contributes to BAS decomposition. Dehydrogenation was further confirmed by exposing the sample to hydrogen to regenerate some of the BAS as monitored by FTIR and MS-TPD.

K Al-majnouni; N Hould; W Lonergan; D Vlachos; R Lobo

2011-12-31T23:59:59.000Z

132

Single event upsets in gallium arsenide dynamic logic  

SciTech Connect

The advantages and disadvantages of using gallium arsenide (GaAs) dynamic logic in computers and digital systems are briefly discussed, especially with respect to space applications. A short introduction to the topology and operation of GaAs Two-Phase Dynamic FET Logic (TDFL) circuits is presented. Experiments for testing the SEU sensitivity of GaAs TDFL, using a laser to create charge collection events, are described. Results are used to estimate the heavy-ion, soft error rate for TDFL in a spacecraft in geosynchronous orbit, and the dependence of the SEU sensitivity on clock frequency, clock voltage, and clock phase. Analysis of the data includes a comparison between the SEU sensitivities of TDFL and the more common static form of GaAs logic, Directly Coupled FET Logic (DCFL). This is the first reported SEU testing of GaAs dynamic logic.

Fouts, D.J. (Naval Postgraduate School, Monterey, CA (United States). ECE Dept.); Weatherford, T. (SFA Inc., Landover, MD (United States)); McMorrow, C.; Melinger, J.S.; Campbell, A.B. (Naval Research Lab., Washington, DC (United States))

1994-12-01T23:59:59.000Z

133

Coated gallium arsenide neutron detectors : results of characterizationmeasurements.  

DOE Green Energy (OSTI)

Effective detection of special nuclear materials (SNM) is essential for reducing the threat associated with stolen or improvised nuclear devices. Passive radiation detection technologies are primarily based on gamma-ray detection and subsequent isotope identification or neutron detection (specific to neutron sources and SNM). One major effort supported by the Department of Homeland Security in the area of advanced passive detection is handheld or portable neutron detectors for search and localization tasks in emergency response and interdiction settings. A successful SNM search detector will not only be able to confirm the presence of fissionable materials but also establish the location of the source in as short of time as possible while trying to minimize false alarms due to varying background or naturally occurring radioactive materials (NORM). For instruments based on neutron detectors, this translates to detecting neutrons from spontaneous fission or alpha-n reactions and being able to determine the direction of the source (or localizing the source through subsequent measurements). Polyethylene-coated gallium arsenide detectors were studied because the detection scheme is based on measuring the signal in the gallium arsenide wafers from the electrical charge of the recoil protons produced from the scattering of neutrons from the hydrogen nucleus. The inherent reaction has a directional dependence because the neutron and hydrogen nucleus have equivalent masses. The assessment and measurement of polyethylene-coated gallium arsenide detector properties and characteristics was the first phase of a project being performed for the Department of Homeland Security and the results of these tests are reported in this report. The ultimate goal of the project was to develop a man-portable neutron detection system that has the ability to determine the direction of the source from the detector. The efficiency of GaAs detectors for different sizes of polyethylene layers and different angles between the detector and the neutron source were determined. Preliminary measurements with a neutron generator based on a deuterium-tritium reaction ({approx}14 MeV neutrons) were performed and the results are discussed. This report presents the results of these measurements in terms of efficiency and angular efficiency and compares them to Monte Carlo calculations to validate the calculation scheme in view of further applications. Based on the results of this study, the polyethylene-coated gallium arsenide detectors provide adequate angular resolution based on proton recoil detection from the neutron scattering reaction from hydrogen. However, the intrinsic efficiency for an individual detector is extremely low. Because of this low efficiency, large surface area detectors ( or a large total surface area from many small detectors) would be required to generate adequate statistics to perform directional detection in near-real time. Large surface areas could be created by stacking the detector wafers with only a negligible attenuation of source neutrons. However, the cost of creating such a large array of GaAs is cost-prohibitive at this time.

Klann, R. T.; Perret, G.; Sanders, J.

2006-09-29T23:59:59.000Z

134

High efficiency III-nitride light-emitting diodes  

DOE Patents (OSTI)

Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

Crawford, Mary; Koleske, Daniel; Cho, Jaehee; Zhu, Di; Noemaun, Ahmed; Schubert, Martin F; Schubert, E. Fred

2013-05-28T23:59:59.000Z

135

Iron-Nitride Alloy Magnets: Transformation Enabled Nitride Magnets Absent Rare Earths (TEN Mare)  

Science Conference Proceedings (OSTI)

REACT Project: Case Western is developing a highly magnetic iron-nitride alloy to use in the magnets that power electric motors found in EVs and renewable power generators. This would reduce the overall price of the motor by eliminating the expensive imported rare earth minerals typically found in today’s best commercial magnets. The iron-nitride powder is sourced from abundant and inexpensive materials found in the U.S. The ultimate goal of this project is to demonstrate this new magnet system, which contains no rare earths, in a prototype electric motor. This could significantly reduce the amount of greenhouse gases emitted in the U.S. each year by encouraging the use of clean alternatives to oil and coal.

None

2012-01-01T23:59:59.000Z

136

Processing and characterization of silicon nitride nanofiber paper  

Science Conference Proceedings (OSTI)

Papers of silicon nitride nanofibers were synthesized by a carbothermal reduction process. These nanofiber papers were synthesized in situ and did not require a secondary processing step. The process utilized silica nanopowders and silica gel as the ...

Kei-Peng Jen, Ronald Warzoha, Ji Guo, Michael Tang, Sridhar Santhanam

2013-01-01T23:59:59.000Z

137

Studies on Plasma Surface Nitriding of Interstitial Free Steel  

Science Conference Proceedings (OSTI)

Plasma nitriding has been carried out at an applied pressure of 5 mbar using a gas mixture of nitrogen (20 %) and hydrogen (80 %) at 450oC for 1-5 h.

138

Molybdenum enhanced low-temperature deposition of crystalline silicon nitride  

DOE Patents (OSTI)

A process for chemical vapor deposition of crystalline silicon nitride is described which comprises the steps of: introducing a mixture of a silicon source, a molybdenum source, a nitrogen source, and a hydrogen source into a vessel containing a suitable substrate; and thermally decomposing the mixture to deposit onto the substrate a coating comprising crystalline silicon nitride containing a dispersion of molybdenum silicide. 5 figures.

Lowden, R.A.

1994-04-05T23:59:59.000Z

139

Low-loss binder for hot pressing boron nitride  

DOE Patents (OSTI)

This report describes an invention utilizing Borazine derivatives as low-loss binders and precursors for making ceramic boron nitirde structures. The derivative forms the same composition as the boron nitride starting material, thereby filling the voids with the same boron nitride material upon forming and hot pressing. The derivatives have a further advantage of being low in carbon thus resulting in less volatile byproduct that can result in bubble formation during pressing.

Maya, L.

1989-06-02T23:59:59.000Z

140

EIA-811 MONTHLY BULK TERMINAL REPORT INSTRUCTIONS  

U.S. Energy Information Administration (EIA)

EIA-811, Monthly Bulk Terminal Report Page 1 U.S. DEPARTMENT OF ENERGY ENERGY IN FORMATION ADMINISTRATION Washington, D.C. 20585 OMB No. 1905-0165

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Bulk Metallic Glasses VIII - Programmaster.org  

Science Conference Proceedings (OSTI)

Aug 2, 2010 ... Sponsorship, The Minerals, Metals and Materials Society .... The Oxidation Behavior of an FeCo-Based Bulk Metallic Glass at 600 - 700C.

142

Inorganic Nanocrystal Bulk Heterojunctions - Energy Innovation ...  

Schematic illustration of a nanocrystal bulk heterojunction solar cell with an active layer in which the concentration of n-type and p-type nanocrystals is graded ...

143

Mechanical Behavior of Bulk Nanocrystalline Copper Alloys ...  

Science Conference Proceedings (OSTI)

Presentation Title, Mechanical Behavior of Bulk Nanocrystalline Copper Alloys Produced by High Energy Ball Milling. Author(s), Hamed Bahmanpour, Khaled M.

144

(Polyfluoroaryl) fluoroanions of aluminum, gallium, and indium of enhanced utility, uses thereof, and products based thereon  

DOE Patents (OSTI)

The (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium are novel weakly coordinating anions which are highly fluorinated. (Polyfluoroaryl)fluoroanions of one such type contain at least one ring substituent other than fluorine. These (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium have greater solubility in organic solvents, or have a coordinative ability essentially equal to or less than that of the corresponding (polyfluoroaryl)fluoroanion of aluminum, gallium, or indium in which the substituent is replaced by fluorine. Another type of new (polyfluoroaryl)fluoroanion of aluminum, gallium, and indium have 1-3 perfluorinated fused ring groups and 2-0 perfluorophenyl groups. When used as a cocatalyst in the formation of novel catalytic complexes with d- or f-block metal compounds having at least one leaving group such as a methyl group, these anions, because of their weak coordination to the metal center, do not interfere in the ethylene polymerization process, while affecting the propylene process favorably, if highly isotactic polypropylene is desired. Thus, the (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of this invention are useful in various polymerization processes such as are described.

Marks, Tobin J. (Evanston, IL); Chen, You-Xian (Midland, MI)

2001-01-01T23:59:59.000Z

145

(Polyfluoroaryl) fluoroanions of aluminum, gallium, and indium of enhanced utility, uses thereof, and products based thereon  

DOE Patents (OSTI)

The (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium are novel weakly coordinating anions which are highly fluorinated. (Polyfluoroaryl)fluoroanions of one such type contain at least one ring substituent other than fluorine. These (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium have greater solubility in organic solvents, or have a coordinative ability essentially equal to or less than that of the corresponding (polyfluoroaryl)fluoroanion of aluminum, gallium, or indium in which the substituent is replaced by fluorine. Another type of new (polyfluoroaryl)fluoroanion of aluminum, gallium, and indium have 1-3 perfluorinated fused ring groups and 2-0 perfluorophenyl groups. When used as a cocatalyst in the formation of novel catalytic complexes with d- or f-block metal compounds having at least one leaving group such as a methyl group, these anions, because of their weak coordination to the metal center, do not interfere in the ethylene polymerization process, while affecting the propylene process favorably, if highly isotactic polypropylene is desired. Thus, the (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of this invention are useful in various polymerization processes such as are described.

Marks, Tobin J. (Evanston, IL); Chen, You-Xian (Midland, MI)

2002-01-01T23:59:59.000Z

146

Bulk Higgs with 4D Gauge Interactions  

E-Print Network (OSTI)

We consider a model with an extra compact dimension in which the Higgs is a bulk field while all other Standard Model fields are confined on a brane. We find that four-dimensional gauge invariance can still be achieved by appropriate modification of the brane action. This changes accordingly the Higgs propagator so that, the Higgs, in all its interactions with Standard Model fields, behaves as an ordinary 4D field, although it has a bulk kinetic term and bulk self-interactions. In addition, it cannot propagate from the brane to the bulk and, thus, no charge can escape into the bulk but it remains confined on the brane. Moreover, the photon remains massless, while the dependence of the Higgs vacuum on the extra dimension induces a mixing between the graviphoton and the Z-boson. This results in a modification of the sensitive \\rho-parameter.

Alex Kehagias; Kyriakos Tamvakis

2005-07-14T23:59:59.000Z

147

Feasibility of breeding in hard spectrum boiling water reactors with oxide and nitride fuels  

E-Print Network (OSTI)

This study assesses the neutronic, thermal-hydraulic, and fuel performance aspects of using nitride fuel in place of oxides in Pu-based high conversion light water reactor designs. Using the higher density nitride fuel ...

Feng, Bo, Ph. D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

148

Electron backscatter diffraction of plutonium-gallium alloys  

Science Conference Proceedings (OSTI)

At Los Alamos National Laboratory a recent experimental technique has been developed to characterize reactive metals, including plutonium arid cerium, using electron backscatter diffraction (EBSD). Microstructural characterization of plutonium and its alloys by EBSD had been previously elusive primarily because of the extreme toxicity and rapid surface oxidation rate associated with plutonium metal. The experimental techniques, which included ion-sputtering the metal surface using a scanning auger microprobe (SAM) followed by vacuum transfer of the sample from the SAM to the scanning electron microscope (SEM), used to obtain electron backscatter diffraction Kikuchi patterns (EBSPs) and orientation maps for plutonium-gallium alloys are described and the initial microstructural observations based on the analysis are discussed. Combining the SEM and EBSD observations, the phase transformation behavior between the {delta} and {var_epsilon} structures was explained. This demonstrated sample preparation and characterization technique is expected to be a powerful means to further understand phase transformation behavior, orientation relationships, and texlure in the complicated plutonium alloy systems.

Boehlert, C. J. (Carl J.); Zocco, T. G. (Thomas G.); Schulze, R. K. (Roland K.); Mitchell, J. N. (Jeremy N.); Pereyra, R. A. (Ramiro A.)

2002-01-01T23:59:59.000Z

149

Cavitation contributes substantially to tensile creep in silicon nitride  

Science Conference Proceedings (OSTI)

During tensile creep of a hot isostatically pressed (HIPed) silicon nitride, the volume fraction of cavities increases linearly with strain; these cavities produce nearly all of the measured strain. In contrast, compressive creep in the same stress and temperature range produces very little cavitation. A stress exponent that increases with stress ({dot {var_epsilon}} {proportional_to} {sigma}{sup n}, 2 < n < 7) characterizes the tensile creep response, while the compressive creep response exhibits a stress dependence of unity. Furthermore, under the same stress and temperature, the material creeps nearly 100 times faster in tension than in compression. Transmission electron microscopy (TEM) indicates that the cavities formed during tensile creep occur in pockets of residual crystalline silicate phase located at silicon nitride multigrain junctions. Small-angle X-ray scattering (SAXS) from crept material quantifies the size distribution of cavities observed in TEM and demonstrates that cavity addition, rather than cavity growth, dominates the cavitation process. These observations are in accord with a model for creep based on the deformation of granular materials in which the microstructure must dilate for individual grains t slide past one another. During tensile creep the silicon nitride grains remain rigid; cavitation in the multigrain junctions allows the silicate to flow from cavities to surrounding silicate pockets, allowing the dilation of the microstructure and deformation of the material. Silicon nitride grain boundary sliding accommodates this expansion and leads to extension of the specimen. In compression, where cavitation is suppressed, deformation occurs by solution-reprecipitation of silicon nitride.

Luecke, W.E.; Wiederhorn, S.M.; Hockey, B.J.; Krause, R.F. Jr.; Long, G.G. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

1995-08-01T23:59:59.000Z

150

Device performance of in situ steam generated gate dielectric nitrided by remote plasma nitridation  

Science Conference Proceedings (OSTI)

In situ steam generated (ISSG) oxides have recently attracted interest for use as gate dielectrics because of their demonstrated reliability improvement over oxides formed by dry oxidation. [G. Minor, G. Xing, H. S. Joo, E. Sanchez, Y. Yokota, C. Chen, D. Lopes, and A. Balakrishna, Electrochem. Soc. Symp. Proc. 99-10, 3 (1999); T. Y. Luo, H. N. Al-Shareef, G. A. Brown, M. Laughery, V. Watt, A. Karamcheti, M. D. Jackson, and H. R. Huff, Proc. SPIE 4181, 220 (2000).] We show in this letter that nitridation of ISSG oxide using a remote plasma decreases the gate leakage current of ISSG oxide by an order of magnitude without significantly degrading transistor performance. In particular, it is shown that the peak normalized transconductance of n-channel devices with an ISSG oxide gate dielectric decreases by only 4% and the normalized drive current by only 3% after remote plasma nitridation (RPN). In addition, it is shown that the reliability of the ISSG oxide exhibits only a small degradation after RPN. These observations suggest that the ISSG/RPN process holds promise for gate dielectric applications. {copyright} 2001 American Institute of Physics.

Al-Shareef, H. N.; Karamcheti, A.; Luo, T. Y.; Bersuker, G.; Brown, G. A.; Murto, R. W.; Jackson, M. D.; Huff, H. R.; Kraus, P.; Lopes, D. (and others)

2001-06-11T23:59:59.000Z

151

The Bulk Viscosity of a Pion Gas  

E-Print Network (OSTI)

We compute the bulk viscosity of a gas of pions at temperatures below the QCD crossover temperature, for the physical value of pion mass, to lowest order in chiral perturbation theory. Bulk viscosity is controlled by number-changing processes which become exponentially slow at low temperatures when the pions become exponentially dilute, leading to an exponentially large bulk viscosity zeta ~ (F_0^8/m_\\pi^5) exp(2m_\\pi/T), where F_0 = 93 MeV is the pion decay constant.

Egang Lu; Guy D. Moore

2011-01-31T23:59:59.000Z

152

Bulk viscosity of N=2* plasma  

E-Print Network (OSTI)

We use gauge theory/string theory correspondence to study the bulk viscosity of strongly coupled, mass deformed SU(N_c) N=4 supersymmetric Yang-Mills plasma, also known as N=2^* gauge theory. For a wide range of masses we confirm the bulk viscosity bound proposed in arXiv:0708.3459. For a certain choice of masses, the theory undergoes a phase transition with divergent specific heat c_V ~ |1-T_c/T|^(-1/2). We show that, although bulk viscosity rapidly grows as T -> T_c, it remains finite in the vicinity of the critical point.

Alex Buchel; Chris Pagnutti

2008-12-18T23:59:59.000Z

153

Cooled silicon nitride stationary turbine vane risk reduction. Final report  

SciTech Connect

The purpose of this program was to reduce the technical risk factors for demonstration of air cooled silicon nitride turbine vanes. The effort involved vane prototype fabrication efforts at two U.S. based gas turbine grade silicon nitride component manufacturers. The efficacy of the cooling system was analyzed via a thermal time/temperature flow test technique previously at UTRC. By having multiple vendors work on parts fabrication, the chance of program success increased for producing these challenging components. The majority of the effort under this contract focused on developing methods for, and producing, the complex thin walled silicon nitride vanes. Components developed under this program will undergo engine environment testing within N00014-96-2-0014.

Holowczak, John

1999-12-31T23:59:59.000Z

154

Silicon nitride protective coatings for silvered glass mirrors  

DOE Patents (OSTI)

A protective diffusion barrier for metalized mirror structures is provided by a layer or coating of silicon nitride which is a very dense, transparent, dielectric material that is impervious to water, alkali, and other impurities and corrosive substances that typically attack the metal layers of mirrors and cause degradation of the mirrors' reflectivity. The silicon nitride layer can be deposited on the substrate prior to metal deposition thereon to stabilize the metal/substrate interface, and it can be deposited over the metal to encapsulate it and protect the metal from corrosion or other degradation. Mirrors coated with silicon nitride according to this invention can also be used as front surface mirrors.

Tracy, C.E.; Benson, D.K.

1984-07-20T23:59:59.000Z

155

Definition: Bulk Electric System | Open Energy Information  

Open Energy Info (EERE)

Bulk Electric System Bulk Electric System Jump to: navigation, search Dictionary.png Bulk Electric System As defined by the Regional Reliability Organization, the electrical generation resources, transmission lines, interconnections with neighboring systems, and associated equipment, generally operated at voltages of 100 kV or higher. Radial transmission facilities serving only load with one transmission source are generally not included in this definition.[1] Related Terms Regional Reliability Organization, transmission lines, transmission line References ↑ Glossary of Terms Used in Reliability Standards An in LikeLike UnlikeLike You like this.Sign Up to see what your friends like. line Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Bulk_Electric_System&oldid=48030

156

INVESTIGATION OF BULK POWER ERCOT (Texas)  

E-Print Network (OSTI)

INVESTIGATION OF BULK POWER MARKETS ERCOT (Texas) November 1, 2000 The analyses and conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2 A. Electric Reliability Council of Texas (ERCOT) . . . . . . . . . . . . . . . . . . . . . . . . 4-2 B. The 1995 Texas Electricity Restructuring Statute

Laughlin, Robert B.

157

Synthesis and Optimization of the Sintering Kinetics of Actinide Nitrides  

SciTech Connect

Research conducted for this NERI project has advanced the understanding and feasibility of nitride nuclear fuel processing. In order to perform this research, necessary laboratory infrastructure was developed; including basic facilities and experimental equipment. Notable accomplishments from this project include: the synthesis of uranium, dysprosium, and cerium nitrides using a novel, low-cost mechanical method at room temperature; the synthesis of phase pure UN, DyN, and CeN using thermal methods; and the sintering of UN and (Ux, Dy1-x)N (0.7 ? X ? 1) pellets from phase pure powder that was synthesized in the Advanced Materials Laboratory at Boise State University.

Drryl P. Butt; Brian Jaques

2009-03-31T23:59:59.000Z

158

Comprehensive Model of Hydrogen Transport into a Solar Cell during Silicon Nitride Processing for Fire-Through Metallization  

DOE Green Energy (OSTI)

A mechanism for the transport of H into a Si solar cell during plasma-enhanced chemical vapor deposition (PECVD) of a hydrogenated silicon nitride (SiN:H) layer and its subsequent fire-through metallization process is described. The PECVD process generates process-induced traps, which ''store'' H at the surface of the solar cell. This stored H is released and diffuses rapidly into the bulk of Si during the high-temperature metallization-firing process. During the ramp-down, the diffused H associates with impurities and defects and passivates them. The firing step partially heals up the surface damage. The proposed model explains a variety of observations and experimental results.

Sopori, B.; Zhang, Y.; Reedy, R.; Jones, K.; Yan, Y.; Al-Jassim, M.; Bathey, B.; Kalejs, J.

2005-02-01T23:59:59.000Z

159

Preconceptual design for separation of plutonium and gallium by ion exchange  

SciTech Connect

The disposition of plutonium from decommissioned nuclear weapons, by incorporation into commercial UO{sub 2}-based nuclear reactor fuel, is a viable means to reduce the potential for theft of excess plutonium. This fuel, which would be a combination of plutonium oxide and uranium oxide, is referred to as a mixed oxide (MOX). Following power generation in commercial reactors with this fuel, the remaining plutonium would become mixed with highly radioactive fission products in a spent fuel assembly. The radioactivity, complex chemical composition, and large size of this spent fuel assembly, would make theft difficult with elaborate chemical processing required for plutonium recovery. In fabricating the MOX fuel, it is important to maintain current commercial fuel purity specifications. While impurities from the weapons plutonium may or may not have a detrimental affect on the fuel fabrication or fuel/cladding performance, certifying the effect as insignificant could be more costly than purification. Two primary concerns have been raised with regard to the gallium impurity: (1) gallium vaporization during fuel sintering may adversely affect the MOX fuel fabrication process, and (2) gallium vaporization during reactor operation may adversely affect the fuel cladding performance. Consequently, processes for the separation of plutonium from gallium are currently being developed and/or designed. In particular, two separation processes are being considered: (1) a developmental, potentially lower cost and lower waste, thermal vaporization process following PuO{sub 2} powder preparation, and (2) an off-the-shelf, potentially higher cost and higher waste, aqueous-based ion exchange (IX) process. While it is planned to use the thermal vaporization process should its development prove successful, IX has been recommended as a backup process. This report presents a preconceptual design with material balances for separation of plutonium from gallium by IX.

DeMuth, S.F.

1997-09-30T23:59:59.000Z

160

Continuous Fiber Ceramic Composite (CFCC) Program: Gaseous Nitridation  

SciTech Connect

Textron has developed a mature process for the fabrication of continuous fiber ceramic composite (CFCC) tubes for application in the aluminum processing and casting industry. The major milestones in this project are System Composition; Matrix Formulation; Preform Fabrication; Nitridation; Material Characterization; Component Evaluation

R. Suplinskas G. DiBona; W. Grant

2001-10-29T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Evaluation and silicon nitride internal combustion engine components  

DOE Green Energy (OSTI)

The feasibility of silicon nitride (Si[sub 3]N[sub 4]) use in internal combustion engines was studied by testing three different components for wear resistance and lower reciprocating mass. The information obtained from these preliminary spin rig and engine tests indicates several design changes are necessary to survive high-stress engine applications. The three silicon nitride components tested were valve spring retainers, tappet rollers, and fuel pump push rod ends. Garrett Ceramic Components' gas-pressure sinterable Si[sub 3]N[sub 4] (GS-44) was used to fabricate the above components. Components were final machined from densified blanks that had been green formed by isostatic pressing of GS-44 granules. Spin rig testing of the valve spring retainers indicated that these Si[sub 3]N[sub 4] components could survive at high RPM levels (9,500) when teamed with silicon nitride valves and lower spring tension than standard titanium components. Silicon nitride tappet rollers showed no wear on roller O.D. or I.D. surfaces, steel axles and lifters; however, due to the uncrowned design of these particular rollers the cam lobes indicated wear after spin rig testing. Fuel pump push rod ends were successful at reducing wear on the cam lobe and rod end when tested on spin rigs and in real-world race applications.

Voldrich, W. (Allied-Signal Aerospace Co., Torrance, CA (United States). Garrett Ceramic Components Div.)

1992-04-01T23:59:59.000Z

162

Boron nitride substrates for high-quality graphene electronics  

E-Print Network (OSTI)

Boron nitride substrates for high-quality graphene electronics C. R. Dean1,2 *, A. F. Young3 , I and J. Hone2 * Graphene devices on standard SiO2 substrates are highly disor- dered, exhibiting report the fabrication and characterization of high-quality exfoliated mono- and bilayer graphene devices

Shepard, Kenneth

163

Boron nitride substrates for high-quality graphene electronics  

E-Print Network (OSTI)

(right axis) versus gate voltage at B ÂĽ 14 T (solid line) and 8.5 T (dashed line) for monolayer grapheneBoron nitride substrates for high-quality graphene electronics C. R. Dean1,2 *, A. F. Young3 , I and J. Hone2 * Graphene devices on standard SiO2 substrates are highly disor- dered, exhibiting

Kim, Philip

164

BORON NITRIDE CAPACITORS FOR ADVANCED POWER ELECTRONIC DEVICES  

DOE Green Energy (OSTI)

This project fabricates long-life boron nitride/boron oxynitride thin film -based capacitors for advanced SiC power electronics with a broad operating temperature range using a physical vapor deposition (PVD) technique. The use of vapor deposition provides for precise control and quality material formation.

N. Badi; D. Starikov; C. Boney; A. Bensaoula; D. Johnstone

2010-11-01T23:59:59.000Z

165

Micro benchtop optics by bulk silicon micromachining  

DOE Patents (OSTI)

Micromachining of bulk silicon utilizing the parallel etching characteristics of bulk silicon and integrating the parallel etch planes of silicon with silicon wafer bonding and impurity doping, enables the fabrication of on-chip optics with in situ aligned etched grooves for optical fibers, micro-lenses, photodiodes, and laser diodes. Other optical components that can be microfabricated and integrated include semi-transparent beam splitters, micro-optical scanners, pinholes, optical gratings, micro-optical filters, etc. Micromachining of bulk silicon utilizing the parallel etching characteristics thereof can be utilized to develop miniaturization of bio-instrumentation such as wavelength monitoring by fluorescence spectrometers, and other miniaturized optical systems such as Fabry-Perot interferometry for filtering of wavelengths, tunable cavity lasers, micro-holography modules, and wavelength splitters for optical communication systems.

Lee, Abraham P. (Walnut Creek, CA); Pocha, Michael D. (Livermore, CA); McConaghy, Charles F. (Livermore, CA); Deri, Robert J. (Pleasanton, CA)

2000-01-01T23:59:59.000Z

166

Ohio Distillate Fuel Oil Stocks at Refineries, Bulk Terminals, and ...  

U.S. Energy Information Administration (EIA)

Ohio Distillate Fuel Oil Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)

167

Wisconsin Propane and Propylene Stocks at Refineries, Bulk ...  

U.S. Energy Information Administration (EIA)

Wisconsin Propane and Propylene Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)

168

Michigan Finished Motor Gasoline Stocks at Refineries, Bulk ...  

U.S. Energy Information Administration (EIA)

Michigan Finished Motor Gasoline Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)

169

Colorado Propane and Propylene Stocks at Refineries, Bulk ...  

U.S. Energy Information Administration (EIA)

Colorado Propane and Propylene Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)

170

Colorado Finished Motor Gasoline Stocks at Refineries, Bulk ...  

U.S. Energy Information Administration (EIA)

Colorado Finished Motor Gasoline Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)

171

South Dakota Distillate Fuel Oil Stocks at Refineries, Bulk ...  

U.S. Energy Information Administration (EIA)

South Dakota Distillate Fuel Oil Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)

172

South Dakota Propane and Propylene Stocks at Refineries, Bulk ...  

U.S. Energy Information Administration (EIA)

South Dakota Propane and Propylene Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)

173

Bulk materials storage handling and transportation  

Science Conference Proceedings (OSTI)

This book contains papers on bulk materials storage, handling, and transportation. Topic areas covered include: mechanical handling; pneumatic conveying; transportation; freight pipeliners; storage and discharge systems; integrated handling systems; automation; environment and sampling; feeders and flow control; structural design; large mobile machines; and grain handling.

Not Available

1983-01-01T23:59:59.000Z

174

Thermodynamic property evaluation and magnetic refrigeration cycle analysis for gadolinium gallium garnet  

SciTech Connect

Based on relevant material property data and previous model formulations, a magnetothermodynamic property map for gadolinium gallium garnet (Gd{sub 3}Ga{sub 5}O{sub 12}) was adapted for refrigeration cycle analysis in the temperature range 4-40 K and the magnetic field range 0-6 T. Employing methods similar to those previously developed for other materials and temperature ranges, assessments of limitations and relative performance were made for Carnot, ideal regenerative, and pseudo-constant field regenerative cycles. It was found that although Carnot cycle limitations on available temperature lift for gadolinium gallium garnet are not as severe as the limitations for materials previously examined, considerable improvement in cooling capacity and temperature lift combinations can be achieved by using regenerative cycles if serious loss mechanisms are avoided.

Murphy, R.W.

1994-12-01T23:59:59.000Z

175

Nano-Scale Nitride-Particle Strengthened High-Temperature Ferritic ...  

Nano-Scale Nitride-Particle Strengthened High-Temperature Ferritic and Martensitic Steels Produced by a Thermo-Mechanical Treatment Process Note: The technology ...

176

L3 Hydrogen Storage in Nitrides by the Use of Ammonia as a ...  

Science Conference Proceedings (OSTI)

A37 Unconventional Method of Nitriding of 316l Austenitic Steel · A38 Role of ..... I24 The Study of Cotton Finishing by Artemsia Argyi Oil Microcapsules.

177

Method and apparatus for use of III-nitride wide bandgap semiconductors in optical communications  

DOE Patents (OSTI)

The present disclosure relates to the use of III-nitride wide bandgap semiconductor materials for optical communications. In one embodiment, an optical device includes an optical waveguide device fabricated using a III-nitride semiconductor material. The III-nitride semiconductor material provides for an electrically controllable refractive index. The optical waveguide device provides for high speed optical communications in an infrared wavelength region. In one embodiment, an optical amplifier is provided using optical coatings at the facet ends of a waveguide formed of erbium-doped III-nitride semiconductor materials.

Hui, Rongqing (Lenexa, KS); Jiang,Hong-Xing (Manhattan, KS); Lin, Jing-Yu (Manhattan, KS)

2008-03-18T23:59:59.000Z

178

Method of preparing uranium nitride or uranium carbonitride bodies  

DOE Patents (OSTI)

Sintered uranium nitride or uranium carbonitride bodies having a controlled final carbon-to-uranium ratio are prepared, in an essentially continuous process, from U.sub.3 O.sub.8 and carbon by varying the weight ratio of carbon to U.sub.3 O.sub.8 in the feed mixture, which is compressed into a green body and sintered in a continuous heating process under various controlled atmospheric conditions to prepare the sintered bodies.

Wilhelm, Harley A. (Ames, IA); McClusky, James K. (Valparaiso, IN)

1976-04-27T23:59:59.000Z

179

Bulk viscosity in quasi particle models  

E-Print Network (OSTI)

We discuss transport properties of dynamical fluid composed of quasi-particles whose masses depend on temperature and charge chemical potentials. Based on the relativistic kinetic theory formulated under the relaxation time approximation, we derive a general expression for the bulk viscosity in the quasi-particle medium. We show that dynamically generated particle masses imply an essential modification of the fluid compressibility. As an application of our results we consider a class of quasi-particle models with the chiral phase transition belonging to O(4) and Z(2) universality class. Based on the Ginzburg-Landau and the scaling theory we study the critical properties of the bulk viscosity zeta near the phase transition. We show that under the relaxation time approximation the zeta is not expected to show singular behavior near the O(4) and Z(2) critical point through static critical exponents.

Sasaki, C

2008-01-01T23:59:59.000Z

180

Bulk viscosity in quasi particle models  

E-Print Network (OSTI)

We discuss transport properties of dynamical fluid composed of quasi-particles whose masses depend on temperature and charge chemical potentials. Based on the relativistic kinetic theory formulated under the relaxation time approximation, we derive a general expression for the bulk viscosity in the quasi-particle medium. We show that dynamically generated particle masses imply an essential modification of the fluid compressibility. As an application of our results we consider a class of quasi-particle models with the chiral phase transition belonging to O(4) and Z(2) universality class. Based on the Ginzburg-Landau and the scaling theory we study the critical properties of the bulk viscosity zeta near the phase transition. We show that under the relaxation time approximation the zeta is not expected to show singular behavior near the O(4) and Z(2) critical point through static critical exponents.

C. Sasaki; K. Redlich

2008-06-29T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Isotopically engineered semiconductors: from the bulk tonanostructures  

SciTech Connect

Research performed with semiconductors with controlled isotopic composition is evolving from the measurement of fundamental properties in the bulk to those measured in superlattices and nanostructures. This is driven in part by interests associated with the fields of 'spintronics' and quantum computing. In this topical review, which is dedicated to Prof. Abstreiter, we introduce the subject by reviewing classic and recent measurements of phonon frequencies, thermal conductivity, bandgap renormalizations, and spin coherence lifetimes in isotopically controlled bulk group IV semiconductors. Next, we review phonon properties measured in isotope heterostructures, including pioneering work made possible by superlattices grown by the group of Prof. Abstreiter. We close the review with an outlook on the exciting future possibilities offered through isotope control in 1, 2, and 3 dimensions that will be possible due to advances in nanoscience.

Ager III, Joel W.; Haller, Eugene E.

2006-04-07T23:59:59.000Z

182

Hydrogen isotope separation utilizing bulk getters  

DOE Patents (OSTI)

Tritium and deuterium are separated from a gaseous mixture thereof, derived from a nuclear fusion reactor or some other source, by providing a casing with a bulk getter therein for absorbing the gaseous mixture to produce an initial loading of the getter, partially desorbing the getter to produce a desorbed mixture which is tritium-enriched, pumping the desorbed mixture into a separate container, the remaining gaseous loading in the getter being deuterium-enriched, desorbing the getter to a substantially greater extent to produce a deuterium-enriched gaseous mixture, and removing the deuterium-enriched mixture into another container. The bulk getter may comprise a zirconium-aluminum alloy, or a zirconium-vanadium-iron alloy. The partial desorption may reduce the loading by approximately fifty percent. The basic procedure may be extended to produce a multistage isotope separator, including at least one additional bulk getter into which the tritium-enriched mixture is absorbed. The second getter is then partially desorbed to produce a desorbed mixture which is further tritium-enriched. The last-mentioned mixture is then removed from the container for the second getter, which is then desorbed to a substantially greater extent to produce a desorbed mixture which is deuterium-enriched. The last-mentioned mixture is then removed so that the cycle can be continued and repeated. The method of isotope separation is also applicable to other hydrogen isotopes, in that the method can be employed for separating either deuterium or tritium from normal hydrogen.

Knize, Randall J. (Los Angeles, CA); Cecchi, Joseph L. (Lawrenceville, NJ)

1991-01-01T23:59:59.000Z

183

Hydrogen isotope separation utilizing bulk getters  

DOE Patents (OSTI)

Tritium and deuterium are separated from a gaseous mixture thereof, derived from a nuclear fusion reactor or some other source, by providing a casing with a bulk getter therein for absorbing the gaseous mixture to produce an initial loading of the getter, partially desorbing the getter to produce a desorbed mixture which is tritium-enriched, pumping the desorbed mixture into a separate container, the remaining gaseous loading in the getter being deuterium-enriched, desorbing the getter to a substantially greater extent to produce a deuterium-enriched gaseous mixture, and removing the deuterium-enriched mixture into another container. The bulk getter may comprise a zirconium-aluminum alloy, or a zirconium-vanadium-iron alloy. The partial desorption may reduce the loading by approximately fifty percent. The basic procedure may be extended to produce a multistage isotope separator, including at least one additional bulk getter into which the tritium-enriched mixture is absorbed. The second getter is then partially desorbed to produce a desorbed mixture which is further tritium-enriched. The last-mentioned mixture is then removed from the container for the second getter, which is then desorbed to a substantially greater extent to produce a desorbed mixture which is deuterium-enriched. The last-mentioned mixture is then removed so that the cycle can be continued and repeated. The method of isotope separation is also applicable to other hydrogen isotopes, in that the method can be employed for separating either deuterium or tritium from normal hydrogen.

Knize, Randall J. (Los Angeles, CA); Cecchi, Joseph L. (Lawrenceville, NJ)

1990-01-01T23:59:59.000Z

184

Hydrogen isotope separation utilizing bulk getters  

DOE Patents (OSTI)

Tritium and deuterium are separated from a gaseous mixture thereof, derived from a nuclear fusion reactor or some other source, by providing a casing with a bulk getter therein for absorbing the gaseous mixture to produce an initial loading of the getter, partially desorbing the getter to produce a desorbed mixture which is tritium-enriched, pumping the desorbed mixture into a separate container, the remaining gaseous loading in the getter being deuterium-enriched, desorbing the getter to a substantially greater extent to produce a deuterium-enriched gaseous mixture, and removing the deuterium-enriched mixture into another container. The bulk getter may comprise a zirconium-aluminum alloy, or a zirconium-vanadium-iron alloy. The partial desorption may reduce the loading by approximately fifty percent. The basic procedure may be extended to produce a multistage isotope separator, including at least one additional bulk getter into which the tritium-enriched mixture is absorbed. The second getter is then partially desorbed to produce a desorbed mixture which is further tritium-enriched. The last-mentioned mixture is then removed from the container for the second getter, which is then desorbed to a substantially greater extent to produce a desorbed mixture which is deuterium-enriched. The last-mentioned mixture is then removed so that the cycle can be continued and repeated. The method of isotope separation is also applicable to other hydrogen isotopes, in that the method can be employed for separating either deuterium or tritium from normal hydrogen. 4 figures.

Knize, R.J.; Cecchi, J.L.

1991-08-20T23:59:59.000Z

185

Biegel, Osman, Yu Analysis of Aluminum-Nitride SOI HiTEC 2000 1 June 11-15, 2000  

E-Print Network (OSTI)

. Bengtsson, M. Bergh, M. Choumas, C. Olesen, and K.O. Jeppson, "Application of Aluminum Nitride Films

Biegel, Bryan

186

(Polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of enhanced utility, uses thereof, and products based thereon  

DOE Patents (OSTI)

The (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium are novel weakly coordinating anions which are are highly fluorinated. (Polyfluoroaryl)fluoroanions of one such type contain at least one ring substituent other than fluorine. These (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium have greater solubility in organic solvents, or have a coordinative ability essentially equal to or less than that of the corresponding (polyfluoroaryl)fluoroanion of aluminum, gallium, or indium in which the substituent is replaced by fluorine. Another type of new (polyfluoroaryl)fluoroanion of aluminum, gallium, and indium have 1-3 perfluorinated fused ring groups and 2-0 perfluorophenyl groups. When used as a cocatalyst in the formation of novel catalytic complexes with d- or f-block metal compounds having at least one leaving group such as a methyl group, these anions, because of their weak coordination to the metal center, do not interefere in the ethylene polymerization process, while affecting the the propylene process favorably, if highly isotactic polypropylene is desired. Thus, the (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of this invention are useful in various polymerization processes such as are described.

Marks, Tobin J. (Evanston, IL); Chen, You-Xian (Midland, MI)

2001-01-01T23:59:59.000Z

187

Controlled Shear Band and Fracture in Bulk Metallic Glasses  

Science Conference Proceedings (OSTI)

Aerospace and Spacecraft Applications for Bulk Metallic Glasses and Matrix Composites · Air Oxidation of a Binary Cu64.5Zr35.5 Bulk Metallic Alloy at 573 ...

188

Superconductivity in gallium-substituted Ba8Si46 clathrates  

E-Print Network (OSTI)

We report a joint experimental and theoretical investigation of superconductivity in Ga-substituted type-I silicon clathrates. We prepared samples of the general formula Ba8Si46-xGax, with different values of x. We show that Ba8Si40Ga6 is a bulk superconductor, with an onset at T-C approximate to 3.3 K. For x=10 and higher, no superconductivity was observed down to T=1.8 K. This represents a strong suppression of superconductivity with increasing Ga content, compared to Ba8Si46 with T-C approximate to 8 K. Suppression of superconductivity can be attributed primarily to a decrease in the density of states at the Fermi level, caused by a reduced integrity of the sp(3)-hybridized networks as well as the lowering of carrier concentration. These results are corroborated by first-principles calculations, which show that Ga substitution results in a large decrease of the electronic density of states at the Fermi level, which explains the decreased superconducting critical temperature within the BCS framework. To further characterize the superconducting state, we carried out magnetic measurements showing Ba8Si40Ga6 to be a type-II superconductor. The critical magnetic fields were measured to be H-C1 approximate to 35 Oe and H-C2 approximate to 8.5 kOe. We deduce the London penetration depth lambda approximate to 3700 A and the coherence length xi(c)approximate to 200 A. Our estimate of the electron-phonon coupling reveals that Ba8Si40Ga6 is a moderate phonon-mediated BCS superconductor.

Li, Yang; Zhang, Ruihong; Liu, Yang; Chen, Ning; Luo, Z. P.; Ma, Xingqiao; Cao, Guohui; Feng, Z. S.; Hu, Chia-Ren; Ross, Joseph H., Jr.

2007-01-01T23:59:59.000Z

189

One step process for producing dense aluminum nitride and composites thereof  

DOE Patents (OSTI)

A one step combustion process for the synthesis of dense aluminum nitride compositions is disclosed. The process comprises igniting pure aluminum powder in a nitrogen atmosphere at a pressure of about 1000 atmospheres or higher. The process enables the production of aluminum nitride bodies to be formed directly in a mold of any desired shape.

Holt, J. Birch (San Jose, CA); Kingman, Donald D. (Danville, CA); Bianchini, Gregory M. (Livermore, CA)

1989-01-01T23:59:59.000Z

190

Development of metal etch mask by single layer lift-off for silicon nitride photonic crystals  

Science Conference Proceedings (OSTI)

We present a method for fabrication of nanoscale patterns in silicon nitride (SiN) using a hard chrome mask formed by metal liftoff with a negative ebeam resists (maN-2401). This approach enables fabrication of a robust etch mask without the need for ... Keywords: Metal liftoff, Nanofabrication, Nanophotonics, Photonic crystals (PC), Silicon nitride (SiN)

Kang-mook Lim; Shilpi Gupta; Chad Ropp; Edo Waks

2011-06-01T23:59:59.000Z

191

Hard and elastic amorphous carbon nitride thin films studied by 13 C nuclear magnetic  

E-Print Network (OSTI)

Hard and elastic amorphous carbon nitride thin films studied by 13 C nuclear magnetic resonance bonding of hard and elastic amorphous carbon nitride (a-CNx) thin films was examined using solid-state 13 on Si 001 substrates at 300 °C. Nanoindentation tests reveal a recovery of 80%, a hardness of 5 GPa

Reilly, Anne

192

Microwave Nitridation of Sintered Reaction Bonded Silicon Parts for Natural Gas Fueled Diesel Engines  

DOE Green Energy (OSTI)

This cooperative project was a joint development program between Eaton Corporation and Lockheed Martin Energy Research (LMER). Cooperative work was of benefit to both parties. ORNL was able to assess up-scale of the microwave nitridation process using a more intricate-shaped part designed for application in advanced diesel engines. Eaton Corporation mined access to microwave facilities and expertise for the nitridation of SRBSN materials. The broad objective of the CRADA established with Eaton Corporation and ORNL was to develop cost-effective silicon nitride ceramics compared to the current materials available. The following conclusions can be made from the work performed under the CRADA: (1) Demonstrated that the binder burnout step can be incorporated into the SRBSN processing in the microwave furnace. (2) Scale-up of the microwave nitridation process using Eaton Corporation parts showed that the nitridation weight gains were essentially identical to those obtained by conventional heating. (3) Combined nitridation and sintering processes using silicon nitride beads as packing powders results in degradation of the mechanical properties. (4) Gelcasting of silicon nitride materials using Eaton Si mixtures was demonstrated.

Edler, J.; Kiggans, J.O.; Suman, A.W.; Tiegs, T.N.

1999-01-01T23:59:59.000Z

193

Ultra-thin ohmic contacts for p-type nitride light emitting devices  

DOE Patents (OSTI)

A semiconductor based Light Emitting Device (LED) can include a p-type nitride layer and a metal ohmic contact, on the p-type nitride layer. The metal ohmic contact can have an average thickness of less than about 25 .ANG. and a specific contact resistivity less than about 10.sup.-3 ohm-cm.sup.2.

Raffetto, Mark (Raleigh, NC); Bharathan, Jayesh (Cary, NC); Haberern, Kevin (Cary, NC); Bergmann, Michael (Chapel Hill, NC); Emerson, David (Chapel Hill, NC); Ibbetson, James (Santa Barbara, CA); Li, Ting (Ventura, CA)

2012-01-03T23:59:59.000Z

194

Process for making boron nitride using sodium cyanide and boron phosphate  

DOE Patents (OSTI)

This is a very simple process for making boron nitride by mixing sodium cyanide and boron phosphate and heating the mixture in an inert atmosphere until a reaction takes place. The product is a white powder of boron nitride that can be used in applications that require compounds that are stable at high temperatures and that exhibit high electrical resistance.

Bamberger, C.E.

1987-02-27T23:59:59.000Z

195

Gallium arsenide thin films on tungsten/graphite substrates. Phase II. Quarterly project report No. 2, December 1, 1977-February 28, 1978  

DOE Green Energy (OSTI)

The objectives of this contract are to investigate thin films of gallium arsenide on tungsten/graphite substrates and to prepare solar cells with an AM1 efficiency of 6% or higher by August 1978. Efforts during this quarter have been directed to: (1) the deposition and characterization of gallium arsenide films on tungsten/graphite substrates by the arsenic and arsine processes, (2) the construction and operation of an apparatus for the deposition of titanium dioxide films, and (3) the fabrication and evaluation of MOS solar cells on tungsten/graphite substrates. Gallium arsenide films have been deposited on tungsten/graphite substrates by the reaction of gallium, hydrogen chloride, and arsenic in a hydrogen flow. The structural and electrical properties of these films are very similar to those obtained by the arsine process. The initial stage of the deposition of gallium arsenide films on tungsten/graphite substrates has been investigated by the scanning electron microscopy.

Chu, S.S.

1978-03-01T23:59:59.000Z

196

Controlling Defect Density in Polymer-Fullerene Bulk Heterojunction ...  

Science Conference Proceedings (OSTI)

Controlling Defect Density in Polymer-Fullerene Bulk Heterojunction Solar Cells by Optimizing ... Engineering Carbon Nanomaterials for Energy Application.

197

Superconductivity in bulk ultrafine-grained metals prepared by high ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2014 TMS Annual Meeting & Exhibition. Symposium , Ultrafine Grained Materials VIII. Presentation Title, Superconductivity in bulk ...

198

Mesoporous TiO2 spheres with a nitridated conducting layer  

Science Conference Proceedings (OSTI)

Nitridated TiO2 mesoporous spheres have been synthesized by hydrothermal processing followed by post-nitridation with NH3. Characterization data reveal a nitridated conducting layer, in addition to a mesoporous, and nanosized building-block morphology resulting in a large surface area. The samples have an average pore size and surface area of, respectively, 10 nm and 87 m2/g. The nitridated TiO2 mesoporous spheres exhibit a high capacity of > 200 mAh/g with good cyclability and high rate capability, as the nitridated conducting layer and favorable morphology of nanosized spheres provides good electrical contact, accommodates cycling induced strain smoothly, and facilitates lithium-ion diffusion.

Yoon, Sukeun [ORNL; Bridges, Craig A [ORNL; Unocic, Raymond R [ORNL; Paranthaman, Mariappan Parans [ORNL

2013-01-01T23:59:59.000Z

199

Improving the bulk data transfer experience  

Science Conference Proceedings (OSTI)

Scientific computations and collaborations increasingly rely on the network to provide high-speed data transfer, dissemination of results, access to instruments, support for computational steering, etc. The Energy Sciences Network is establishing a science data network to provide user driven bandwidth allocation. In a shared network environment, some reservations may not be granted due to the lack of available bandwidth on any single path. In many cases, the available bandwidth across multiple paths would be sufficient to grant the reservation. In this paper we investigate how to utilize the available bandwidth across multiple paths in the case of bulk data transfer.

Guok, Chin; Guok, Chin; Lee, Jason R.; Berket, Karlo

2008-05-07T23:59:59.000Z

200

Hanford ETR Bulk Vitrification System - Demonstration Bulk Vitrification System (DBVS) Review Report  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

A Comprehensive Technical A Comprehensive Technical Review of the Demonstration Bulk Vitrification System Technical Assessment Conducted by an Independent and External Team of Experts Volume 1 September 28, 2006 Chartered by CH2M HILL Hanford Group, Inc. Richland, Washington 99352 RPP-31314 Executive Summary In May 2006, CH2M HILL Hanford Group, Inc. chartered an Expert Review Panel (ERP) to review the current status of the Demonstration Bulk Vitrification System (DBVS). It is the consensus of the ERP that bulk vitrification is a technology that requires further development and evaluation to determine its potential for meeting the Hanford waste stabilization mission. No fatal flaws (issues that would jeopardize the overall DBVS mission that cannot be mitigated) were found, given the current state of the project.

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
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201

Thin film gallium arsenide solar cell research. Third quarterly project report, September 1, 1980-November 30, 1980. [Antireflection coating  

DOE Green Energy (OSTI)

The major objective of this contract is to produce gallium arsenide solar cells of 10% conversion efficiency in films of less than 10 micrometers thick which have been deposited by chemical vapor deposition on graphite or tungsten coated graphite substrates. Major efforts during this quarter were directed to: (1) the optimization of the deposition of gallium arsenide films of 10 ..mu..m thickness or less on tungsten/graphic substrates, (2) the investigation of the effectiveness of various grain boundary passivation techniques, (3) the deposition of tantalum pentoxide by ion beam sputtering as an antireflection coating, (4) the deposition of gallium aluminium arsenide by the organometallic process, and (5) the fabrication and characterization of large area Schottky barrier type solar cells from gallium arsenide films of about 10 ..mu..m thickness. Various grain boundary passivation techniques, such as the anodic oxidation, thermal oxidation, and ruthenium treatment, have been investigated. The combination of thermal oxidation and ruthenium treatment has been used to fabricate Schottky barrier type solar cells. Large area MOS solar cells of 9 cm/sup 2/ area with AMl efficiency of 8.5% have been fabricated from ruthenium treated gallium arsenide films of 10 ..mu..m thickness. The construction of the apparatus for the deposition of gallium aluminum arsenide by the organometallic process has been completed. The deposition of good quality tantalum pentoxide film as an antireflection coating has been carried out by the ion beam sputtering technique. The short-circuit current density and AMl efficiency of the solar cells are increased by approximately 60%, with a slight increase in the open-circuit voltage. Details are presented. (WHK)

Chu, S. S.

1980-12-01T23:59:59.000Z

202

Kinetics for the reaction of hydrogen with a plutonium-1 weight percent gallium alloy powder  

Science Conference Proceedings (OSTI)

Kinetics for the reaction of hydrogen with plutonium-1 w/o gallium were measured using powder prepared ''in situ.'' The rates obeyed a first-order rate law and were independent of temperature from -29/degree/ to 355/degree/C. A pressure dependence proportional to P/sup //one-half/ was observed at pressures less than 1 kPa. From 1 to 70 kPa the pressure dependence rapidly decreased. Total pressure dependence could be accurately described by a Langmuir equation. Results indicate an adsorption-controlled reaction at low pressures and a reaction-controlled process at high pressure. 19 refs.

Stakebake, J.L.

1981-11-01T23:59:59.000Z

203

Molecular Level Assessment of Thermal Transport and Thermoelectricity in Materials: From Bulk Alloys to Nanostructures  

E-Print Network (OSTI)

The ability to manipulate material response to dynamical processes depends on the extent of understanding of transport properties and their variation with chemical and structural features in materials. In this perspective, current work focuses on the thermal and electronic transport behavior of technologically important bulk and nanomaterials. Strontium titanate is a potential thermoelectric material due to its large Seebeck coefficient. Here, first principles electronic band structure and Boltzmann transport calculations are employed in studying the thermoelectric properties of this material in doped and deformed states. The calculations verified that excessive carrier concentrations are needed for this material to be used in thermoelectric applications. Carbon- and boron nitride-based nanomaterials also offer new opportunities in many applications from thermoelectrics to fast heat removers. For these materials, molecular dynamics calculations are used to evaluate lattice thermal transport. To do this, first, an energy moment term is reformulated for periodic boundary conditions and tested to calculate thermal conductivity from Einstein relation in various systems. The influences of the structural details (size, dimensionality) and defects (vacancies, Stone-Wales defects, edge roughness, isotopic disorder) on the thermal conductivity of C and BN nanostructures are explored. It is observed that single vacancies scatter phonons stronger than other type of defects due to unsatisfied bonds in their structure. In pristine states, BN nanostructures have 4-6 times lower thermal conductivity compared to C counterparts. The reason of this observation is investigated on the basis of phonon group velocities, life times and heat capacities. The calculations show that both phonon group velocities and life times are smaller in BN systems. Quantum corrections are also discussed for these classical simulations. The chemical and structural diversity that could be attained by mixing hexagonal boron nitride and graphene provide further avenues for tuning thermal and electronic properties. In this work, the thermal conductivity of hybrid graphene/hexagonal-BN structures: stripe superlattices and BN (graphene) dots embedded in graphene (BN) are studied. The largest reduction in thermal conductivity is observed at 50% chemical mixture in dot superlattices. The dot radius appears to have little effect on the magnitude of reduction around large concentrations while smaller dots are more influential at dilute systems.

Kinaci, Alper

2013-05-01T23:59:59.000Z

204

Interface control of bulk ferroelectric polarization  

SciTech Connect

The control of material interfaces at the atomic level has led to no- vel interfacial properties and functionalities. In particular, the study of polar discontinuities at interfaces between complex oxides lies at the frontier of modern condensed matter research. Here we em- ploy a combination of experimental measurements and theoretical calculations to demonstrate the control of a bulk property, namely ferroelectric polarization, of a heteroepitaxial bilayer by precise atomic-scale interface engineering. More specifically, the control is achieved by exploiting the interfacial valence mismatch to influence the electrostatic potential step across the interface, which manifests itself as the biased-voltage in ferroelectric hysteresis loops and determines the ferroelectric state. A broad study of diverse systems comprising different ferroelectrics and conducting perovskite un- derlayers extends the generality of this phenomenon.

Yu, P [University of California, Berkeley; Luo, Weidong [ORNL; Yi, D. [University of California, Berkeley; Zhang, J.-X. [University of California, Berkeley; Rossell, M.D. [Lawrence Berkeley National Laboratory (LBNL); Yang, C.-H. [Korea Advanced Institute of Science and Technology; You, L. [University of California, Berkeley; Singh-Bhalla, G. B. [University of California, Berkeley & LBNL; Yang, S.Y [University of California, Berkeley; He, Q [University of California, Berkeley; Ramasse, Q. M. [Lawrence Berkeley National Laboratory (LBNL); Erni, R. [Lawrence Berkeley National Laboratory (LBNL); Martin, L. W. [University of Illinois, Urbana-Champaign; Chu, Y. H. [University of California, Berkeley; Pantelides, Sokrates T [ORNL; Pennycook, Stephen J [ORNL; Ramesh, R. [University of California, Berkeley

2012-01-01T23:59:59.000Z

205

Charm mass effects in bulk channel correlations  

E-Print Network (OSTI)

The bulk viscosity of thermalized QCD matter at temperatures above a few hundred MeV could be significantly influenced by charm quarks because their contribution arises four perturbative orders before purely gluonic effects. In an attempt to clarify the challenges of a lattice study, we determine the relevant imaginary-time correlator (of massive scalar densities) up to NLO in perturbation theory, and compare with existing data. We find discrepancies much larger than in the vector channel; this may hint, apart from the importance of taking a continuum limit, to larger non-perturbative effects in the scalar channel. We also recall how a transport peak related to the scalar density spectral function encodes non-perturbative information concerning the charm quark chemical equilibration rate close to equilibrium.

Y. Burnier; M. Laine

2013-09-06T23:59:59.000Z

206

Organic hybrid planar-nanocrystalline bulk heterojunctions  

DOE Patents (OSTI)

A photosensitive optoelectronic device having an improved hybrid planar bulk heterojunction includes a plurality of photoconductive materials disposed between the anode and the cathode. The photoconductive materials include a first continuous layer of donor material and a second continuous layer of acceptor material. A first network of donor material or materials extends from the first continuous layer toward the second continuous layer, providing continuous pathways for conduction of holes to the first continuous layer. A second network of acceptor material or materials extends from the second continuous layer toward the first continuous layer, providing continuous pathways for conduction of electrons to the second continuous layer. The first network and the second network are interlaced with each other. At least one other photoconductive material is interspersed between the interlaced networks. This other photoconductive material or materials has an absorption spectra different from the donor and acceptor materials.

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

2011-03-01T23:59:59.000Z

207

Organic hybrid planar-nanocrystalline bulk heterojunctions  

DOE Patents (OSTI)

A photosensitive optoelectronic device having an improved hybrid planar bulk heterojunction includes a plurality of photoconductive materials disposed between the anode and the cathode. The photoconductive materials include a first continuous layer of donor material and a second continuous layer of acceptor material. A first network of donor material or materials extends from the first continuous layer toward the second continuous layer, providing continuous pathways for conduction of holes to the first continuous layer. A second network of acceptor material or materials extends from the second continuous layer toward the first continuous layer, providing continuous pathways for conduction of electrons to the second continuous layer. The first network and the second network are interlaced with each other. At least one other photoconductive material is interspersed between the interlaced networks. This other photoconductive material or materials has an absorption spectra different from the donor and acceptor materials.

Forrest, Stephen R.; Yang, Fan

2013-04-09T23:59:59.000Z

208

DEVELOPMENT OF THE BULK TRITIUM SHIPPING PACKAGING  

SciTech Connect

A new radioactive shipping packaging for transporting bulk quantities of tritium, the Bulk Tritium Shipping Package (BTSP), has been designed for the Department of Energy (DOE) as a replacement for a package designed in the early 1970s. This paper summarizes significant design features and describes how the design satisfies the regulatory safety requirements of the Code of Federal Regulations and the International Atomic Energy Agency. The BTSP design incorporates many improvements over its predecessor by implementing improved testing, handling, and maintenance capabilities, while improving manufacturability and incorporating new engineered materials. This paper also discusses the results from testing of the BTSP to 10 CFR 71 Normal Conditions of Transport and Hypothetical Accident Condition events. The programmatic need of the Department of Energy (DOE) to ship bulk quantities of tritium has been satisfied since the late 1970s by the UC-609 shipping package. The current Certificate of Conformance for the UC-609, USA/9932/B(U) (DOE), will expire in late 2011. Since the UC-609 was not designed to meet current regulatory requirements, it will not be recertified and thereby necessitates a replacement Type B shipping package for continued DOE tritium shipments in the future. A replacement tritium packaging called the Bulk Tritium Shipping Package (BTSP) is currently being designed and tested by Savannah River National Laboratory (SRNL). The BTSP consists of two primary assemblies, an outer Drum Assembly and an inner Containment Vessel Assembly (CV), both designed to mitigate damage and to protect the tritium contents from leaking during the regulatory Hypothetical Accident Condition (HAC) events and during Normal Conditions of Transport (NCT). During transport, the CV rests on a silicone pad within the Drum Liner and is covered with a thermal insulating disk within the insulated Drum Assembly. The BTSP packaging weighs approximately 500 lbs without contents and is 50-1/2 inches high by 24-1/2 inches in outside diameter. With contents the gross weight of the BTSP is 650 lbs. The BTSP is designed for the safe shipment of 150 grams of tritium in a solid or gaseous state. To comply with the federal regulations that govern Type B shipping packages, the BTSP is designed so that it will not lose tritium at a rate greater than the limits stated in 10CFR 71.51 of 10{sup -6} A2 per hour for the 'Normal Conditions of Transport' (NCT) and an A2 in 1 week under 'Hypothetical Accident Conditions' (HAC). Additionally, since the BTSP design incorporates a valve as part of the tritium containment boundary, secondary containment features are incorporated in the CV Lid to protect against gas leakage past the valve as required by 10CFR71.43(e). This secondary containment boundary is designed to provide the same level of containment as the primary containment boundary when subjected to the HAC and NCT criteria.

Blanton, P.; Eberl, K.

2008-09-14T23:59:59.000Z

209

Bulk Heterojunction Organic Photovoltaic Devices Using Dendrimers  

Science Conference Proceedings (OSTI)

A family of prototype ..pi..-conjugated dendrimers has been synthesized and incorporated into solution-processable organic photovoltaic (OPV) devices. Bulk heterojunction devices were fabricated by blending the dendrimers with a solubilized fullerene. The best of these initial devices, which were not optimized for morphology, exhibited external quantum efficiencies of 22% at peak wavelength. It was found that 3-arm dendrimers, when sufficiently soluble, yielded higher photocurrents than their 4-arm counterparts. This was attributed to better planarity and intermolecular alignment of the 3-arm version. Device efficiency was seen to increase with increasing arm length. A reduced-band gap dendrimer was synthesized by attaching electron-withdrawing groups onto the core to yield an optical band gap of 1.82 eV.

Kopidakis, N.; Mitchell, W. J.; Bozell, J. J.; Piris, J.; Ginley, D. S.; Rumbles, G.; Shaheen S. E.

2005-11-01T23:59:59.000Z

210

Dynamics of formation of photoresponse in a detector structure made of gallium arsenide  

SciTech Connect

The influence of capture effects on the characteristics of detectors of the ionizing radiation based on semi-insulating gallium arsenide is considered. Generation of nonequilibrium electrons and holes along the entire thickness of the active region was performed under illumination with an infrared light-emitting diode with a wavelength of 0.9 {mu}m. In this case, the situation emerging in the device structure under the effect of X-ray radiation or a high-energy electron beam was simulated. It is shown that the variation in the shape of the output signal with time in this case is caused by variation in the electric field profile due to the capture of holes at deep centers in gallium arsenide. An absolutely different distribution of the electric field emerges in the structure under irradiation of a semitransparent cathode of the structure with a red light-emitting diode, emission of which penetrates into the active region for mere 1 {mu}m. In this case, the transformation of the electric field is caused by the capture of electrons. Under the prolonged effect of such radiation, a space-charge-limited current mode emerges in the device.

Ayzenshtat, G. I., E-mail: ayzen@mail.tomsknet.ru; Lelekov, M. A.; Tolbanov, O. P. [Tomsk State University (Russian Federation)

2008-04-15T23:59:59.000Z

211

Anionic Gallium-Based Metal;#8722;Organic Framework and Its Sorption and Ion-Exchange Properties  

SciTech Connect

A gallium-based metal-organic framework Ga{sub 6}(C{sub 9}H{sub 3}O{sub 6}){sub 8} {center_dot} (C{sub 2}H{sub 8}N){sub 6}(C{sub 3}H{sub 7}NO){sub 3}(H{sub 2}O){sub 26} [1, Ga{sub 6}(1,3,5-BTC){sub 8} {center_dot} 6DMA {center_dot} 3DMF {center_dot} 26H{sub 2}O], GaMOF-1; BTC = benzenetricarboxylate/trimesic acid and DMA = dimethylamine, with space group I{bar 4}3d, a = 19.611(1) {angstrom}, and V = 7953.4(6) {angstrom}{sup 3}, was synthesized using solvothermal techniques and characterized by synchrotron-based X-ray microcrystal diffraction. Compound 1 contains isolated gallium tetrahedra connected by the organic linker (BTC) forming a 3,4-connected anionic porous network. Disordered positively charged ions and solvent molecules are present in the pore, compensating for the negative charge of the framework. These positively charged molecules could be exchanged with alkali-metal ions, as is evident by an ICP-MS study. The H{sub 2} storage capacity of the parent framework is moderate with a H{sub 2} storage capacity of {approx}0.5 wt % at 77 K and 1 atm.

Banerjee, Debasis; Kim, Sun Jin; Wu, Haohan; Xu, Wenqian; Borkowski, Lauren A.; Li, Jing; Parise, John B. (Kwangju); (Rutgers); (SBU)

2012-04-30T23:59:59.000Z

212

Synthesis and Characterization of Bulk Nano Crystalline Pb Free ...  

Science Conference Proceedings (OSTI)

High energy ball milling route was adopted for production of bulk nano crystalline solders from these alloy powders. The milling was carried out for a period of ...

213

Vibrated Bulk Density (VBD) of Calcined Petroleum Coke and ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Vibrated bulk density (VBD) is a quantitative measurement used in the aluminum industry to evaluate the density of calcined petroleum coke.

214

Vibrated Bulk Density (VBD) of Calcined Petroleum Coke and ...  

Science Conference Proceedings (OSTI)

Presentation Title, Vibrated Bulk Density (VBD) of Calcined Petroleum Coke and Implications of Changes in the ASTM Method D4292. Author(s), Bill Spencer, ...

215

Fabrication of Bulk Metallic Glass Foams via Severe Plastic ...  

Science Conference Proceedings (OSTI)

Symposium, M. Bulk Metallic Glasses, Nanocrystalline Materials, and ... Application of Metallic Glass for High Performance Si Solar Cell: Oxidation Behavior of ...

216

Bulk Metallic Glass Composites Fabricated within the Supercooled ...  

Science Conference Proceedings (OSTI)

In the present work, lightweight magnesium base Bulk Metallic Glass Composites ... Application of Metallic Glass for High Performance Si Solar Cell: Oxidation ...

217

Washington, D. C. 20585 EIA-815 MONTHLY BULK TERMINAL AND ...  

U.S. Energy Information Administration (EIA)

instructions, please contact the Manager at Survey (202) 586-3536. PURPOSE . ... often blending of petroleum products and has total bulk shell

218

Innovative approaches to improve bulk heterojuction organic photovoltaic device performance.  

E-Print Network (OSTI)

??In this thesis we studied the electrical properties of bulk heterojunction organic photovoltaic (OPV) devices fabricated using a variety of conjugated polymers, including regioregular P3HT,… (more)

Zhang, Ye

2010-01-01T23:59:59.000Z

219

Gulf Coast (PADD 3) Refinery Grade Butane Stocks at Bulk ...  

U.S. Energy Information Administration (EIA)

Gulf Coast (PADD 3) Refinery Grade Butane Stocks at Bulk Terminals (Thousand Barrels) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec; 2005: 935: ...

220

Modular Electromechanical Batteries for Cost-Effective Bulk ...  

The "new breed" of flywheel under development at the Lawrence Livermore National Laboratory is aimed specifically at the "bulk storage" of electrical energy where the ...

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Boron-Nitride (BN) Nanotubes (BNNT) at TJNAF| U.S. DOE Office of Science  

Office of Science (SC) Website

Boron-Nitride (BN) Nanotubes (BNNT) at Boron-Nitride (BN) Nanotubes (BNNT) at TJNAF Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Boron-Nitride (BN) Nanotubes (BNNT) at TJNAF Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Boron-Nitride (BN) Nanotubes (BNNT) Developed at: Jefferson Lab Free Electron Facility Developed in: 2008-2011

222

Method of enhancing the wettability of boron nitride for use as an electrochemical cell separator  

DOE Patents (OSTI)

A felt or other fabric of boron nitride suitable for use as an interelectrode separator within an electrochemical cell is wetted with a solution containing a thermally decomposable organic salt of an alkaline earth metal. An aqueous solution of magnesium acetate is the preferred solution for this purpose. After wetting the boron nitride, the solution is dried by heating at a sufficiently low temperature to prevent rapid boiling and the creation of voids within the separator. The dried material is then calcined at an elevated temperature in excess of 400/sup 0/C to provide a coating of an oxide of magnesium on the surface of the boron nitride fibers. A fabric or felt of boron nitride treated in this manner is easily wetted by molten electrolytic salts, such as the alkali metal halides or alkaline earth metal halides, that are used in high temperature, secondary electrochemical cells.

McCoy, L.R.

1981-01-23T23:59:59.000Z

223

Optoelectronic Properties in Monolayers of Hybridized Graphene and Hexagonal Boron Nitride  

E-Print Network (OSTI)

We explain the nature of the electronic energy gap and optical absorption spectrum of carbon–boron-nitride (CBN) monolayers using density functional theory, GW and Bethe-Salpeter calculations. The band structure and the ...

Bernardi, Marco

224

Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves  

DOE Patents (OSTI)

A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Tiegs, Terry N. (Lenoir City, TN)

1992-01-01T23:59:59.000Z

225

Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves  

DOE Patents (OSTI)

A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Holcombe, C.E.; Dykes, N.L.; Tiegs, T.N.

1992-10-13T23:59:59.000Z

226

Process for preparing transition metal nitrides and transition metal carbonitrides and their reaction intermediates  

DOE Patents (OSTI)

Disclosed is a process for making ammonolytic precursors to nitride and carbonitride ceramics. Extreme reaction conditions are not required and the precursor is a powder-like substance that produces ceramics of improved purity and morphology upon pyrolysis.

Maya, L.

1986-12-09T23:59:59.000Z

227

Electronic structure analyses and activation studies of a dinitrogen-derived terminal nitride of molybdenum  

E-Print Network (OSTI)

Chapter 1: Complexes obtained by electrophilic attack on a dinitrogen-derived terminal molybdenum nitride: Electronic structure analysis by solid state CP/MAS ą?N NMR in combination ... Chapter 2. Carbene chemistry in the ...

Sceats, Emma Louise, 1978-

2004-01-01T23:59:59.000Z

228

Recent development of the synthesis and engineering applications of one-dimensional boron nitride nanomaterials  

Science Conference Proceedings (OSTI)

One-dimensional (1D) nanomaterials with novel photoelectric, magnetic, mechanical, and electronic transport properties have long been the research focus throughout the world. Herein, the recent achievements in preparation of 1D boron nitride nanomaterials, ...

Changhui Sun; Hongxiao Yu; Liqiang Xu; Qiang Ma; Yitai Qian

2010-01-01T23:59:59.000Z

229

Spin current switching and spin-filtering effects in Mn-doped boron nitride nanoribbons  

Science Conference Proceedings (OSTI)

The spin transport properties are investigated by means of the first principle approach for boron nitride nanoribbons with one or two substitutional Mn impurities, connected to graphene electrodes. The spin current polarization is evaluated using the ...

G. A. Nemnes

2012-01-01T23:59:59.000Z

230

Proton exchange membrane fuel cells with chromium nitride nanocrystals as electrocatalysts  

E-Print Network (OSTI)

S. Srinivasan, V. Antonucci, Fuel Cells 1, 133 (2001). 15 Y.Proton exchange membrane fuel cells with chromium nitridePolymer electrolyte membrane fuel cells (PEMFCs) are energy

Zhong, Hexiang; Chen, Xiaobo; Zhang, Huamin; Wang, Meiri; Mao, Samuel S.

2007-01-01T23:59:59.000Z

231

Texas Bulk Power Study-- An Overview  

E-Print Network (OSTI)

In the 1980's, several significant changes have evolved in markets for electric power in Texas. Cogeneration, fuel market volatility, electric system reliability, generation and transmission facility construction delays, construction cost escalation, regional disparities in load growth, severe economic cycles, and a variety of legal, health and environmental issues have contributed to increasing uncertainty in the utility planning process. Through more coordination and power pooling among the state's major utilities within the Electric Reliability Council of Texas (ERCOT), a potentially higher level of bulk power transactions may reduce some uncertainty and result in cost savings to the utilities involved. However, both the transactions potential and any corresponding changes in operating costs are quite sensitive to assumptions about the price of natural gas for use as a utility boiler fuel. A large computer model which simulates the operation of the utilities under the extreme boundary conditions of zero transactions and fully coordinated economic dispatch results in a range of transactions from 5% to 14% of total system energy requirements and a range of cost savings from less than 1% to nearly 6% of the ERCOT system variable operating costs.

Moore, B.

1988-09-01T23:59:59.000Z

232

Nitride III-V Activities at Sandia National Labs  

NLE Websites -- All DOE Office Websites (Extended Search)

Lighting: Lighting: Synergisms with Office of Science Materials Programs Jerry A. Simmons Semiconductor Materials and Device Sciences Sandia National Laboratories March 13, 2001 EMaCC Meeting OUTLINE *Brief overview of prospects & promise of SSL *National Initiative *Grand Challenge LDRD at Sandia *BES-supported activities at Sandia provided core capabilities *Other NS applications of nitride materials science Will only discuss inorganic materials and devices here. Major motivation for SSL is energy savings: lighting is large fraction of energy consumption 1 10 100 1000 1970 1980 1990 2000 2010 2020 Energy Electricity Illumination (assuming 20% of electricity) Projected WORLD Energy Consumption (Quads) Year 400 Quads 130 Quads 25 Quads 1998 1970 1980 1990 2000 2010 2020 Energy Electricity Illumination

233

ICP dry etching of III-V nitrides  

DOE Green Energy (OSTI)

Inductively coupled plasma etching of GaN, AlN, InN, InGaN and InAlN was investigated in CH{sub 4}/H{sub 2}/Ar plasmas as a function of dc bias, and ICP power. The etch rates were generally quite low, as is common for III-nitrides in CH{sub 4} based chemistries. The etch rates increased with increasing dc bias. At low rf power (150 W), the etch rates increased with increasing ICP power, while at 350 W rf power, a peak was found between 500 and 750 W ICP power. The etched surfaces were found to be smooth, while selectivities of etch were {le} 6 for InN over GaN, AlN, InGaN and InAlN under all conditions.

Vartuli, C.B.; Lee, J.W.; MacKenzie, J.D. [Univ. of Florida, Gainesville, FL (United States)] [and others

1997-10-01T23:59:59.000Z

234

High Surface Area Molybdenum Nitride Support for Fuel Cell Electrodes  

SciTech Connect

Alternative supports for polymer electrolyte membrane fuel cells were synthesized and catalytic activity was explored using electrochemical analysis. High surface area, molybdenum nitride supports were synthesized by rapidly heating a gel of polyethyleneimine bound molybdenum in a tube furnace under a forming gas atmosphere. Subsequent disposition of platinum through an incipient wetness approach lead to dispersed crystallites of platinum on the conductive support. All the ceramic materials were characterized with XRD, SEM, TEM and electrochemical analysis. The supports without platinum are highly stable to acidic aqueous conditions and show no signs of oxygen reduction reactivity (ORR). However, once the 20 wt % platinum is added to the material, ORR activity comparable to XC72 based materials is observed.

Blackmore, Karen [Los Alamos National Laboratory (LANL); Elbaz, L [Los Alamos National Laboratory (LANL); Bauer, E D [Los Alamos National Laboratory (LANL); Brosha, Eric [Los Alamos National Laboratory (LANL); More, Karren Leslie [ORNL; Mccleskey, T [Los Alamos National Laboratory (LANL); Burrell, A [Los Alamos National Laboratory (LANL)

2011-01-01T23:59:59.000Z

235

Role of defects in III-nitride based electronics  

DOE Green Energy (OSTI)

The LDRD entitled ``Role of Defects in III-Nitride Based Devices'' is aimed to place Sandia National Laboratory at the forefront of the field of GaN materials and devices by establishing a scientific foundation in areas such as material growth, defect characterization/modeling, and processing (metalization and etching) chemistry. In this SAND report the authors summarize their studies such as (1) the MOCVD growth and doping of GaN and AlGaN, (2) the characterization and modeling of hydrogen in GaN, including its bonding, diffusion, and activation behaviors, (3) the calculation of energetic of various defects including planar stacking faults, threading dislocations, and point defects in GaN, and (4) dry etching (plasma etching) of GaN (n- and p-types) and AlGaN. The result of the first AlGaN/GaN heterojunction bipolar transistor is also presented.

HAN,JUNG; MYERS JR.,SAMUEL M.; FOLLSTAEDT,DAVID M.; WRIGHT,ALAN F.; CRAWFORD,MARY H.; LEE,STEPHEN R.; SEAGER,CARLETON H.; SHUL,RANDY J.; BACA,ALBERT G.

2000-01-01T23:59:59.000Z

236

Bulk Vitrification Castable Refractory Block Protection Study  

Science Conference Proceedings (OSTI)

Bulk vitrification (BV) was selected for a pilot-scale test and demonstration facility for supplemental treatment to accelerate the cleanup of low-activity waste (LAW) at the Hanford U.S. DOE Site. During engineering-scale (ES) tests, a small fraction of radioactive Tc (and Re, its nonradioactive surrogate) were transferred out of the LAW glass feed and molten LAW glass, and deposited on the surface and within the pores of the castable refractory block (CRB). Laboratory experiments were undertaken to understand the mechanisms of the transport Tc/Re into the CRB during vitrification and to evaluate various means of CRB protection against the deposition of leachable Tc/Re. The tests used Re as a chemical surrogate for Tc. The tests with the baseline CRB showed that the molten LAW penetrates into CRB pores before it converts to glass, leaving deposits of sulfates and chlorides when the nitrate components decompose. Na2O from the LAW reacts with the CRB to create a durable glass phase that may contain Tc/Re. Limited data from a single CRB sample taken from an ES experiment indicate that, while a fraction of Tc/Re is present in the CRB in a readily leachable form, most of the Tc/Re deposited in the refractory is retained in the form of a durable glass phase. In addition, the molten salts from the LAW, mainly sulfates, chlorides, and nitrates, begin to evaporate from BV feeds at temperatures below 800 C and condense on solid surfaces at temperatures below 530 C. Three approaches aimed at reducing or preventing the deposition of soluble Tc/Re within the CRB were proposed: metal lining, sealing the CRB surface with a glaze, and lining the CRB with ceramic tiles. Metal liners were deemed unsuitable because evaluations showed that they can cause unacceptable distortions of the electric field in the BV system. Sodium silicate and a low-alkali borosilicate glaze were selected for testing. The glazes slowed down molten salt condensate penetration, but did little to reduce the penetration of molten salt. Out of several refractory tile candidates, only greystone and fused-cast alumina-zirconia-silica (AZS) refractory remained intact and well bonded to the CRB after firing to 1000 C. The deformation of the refractory-tile composite was avoided by prefiring the greystone tile to 800 C. Condensed vapors did not penetrate the tiles, but Re salts condensed on their surface. Refractory corrosion tests indicated that a 0.25-inch-thick greystone tile would not corrode during a BV melt. Tiles can reduce both vapor penetration and molten salt penetration, but vapor deposition above the melt line will occur even on tiles. The Tc/Re transport scenario was outlined as follows. At temperatures below 700 C, molten ionic salt (MIS) that includes all the Tc/Re penetrates, by capillarity, from the feed into the CRB open porosity. At approximately 750 C, the MIS decomposes through the loss of NOx, leaving mainly sulfate and chloride salts. The Na2O formed in the decomposition of the nitrates reacts with insoluble grains in the feed and with the aluminosilicates in the CRB to form more viscous liquids that reduce further liquid penetration into the CRB. At 800 to 1000 C, a continuous glass phase traps the remains of the MIS in the form of inclusions in the bulk glass melt. At 1000 to 1200 C, the salt inclusions in the glass slowly dissolve but also rise to the surface. The Tc/Re salts also evaporate from the free surface of the glass melt that is rapidly renewed by convective currents. The vapors condense on cooler surfaces in the upper portion of the CRB, the box lid, and the off-gas system.

Hrma, Pavel R.; Bagaasen, Larry M.; Beck, Andrew E.; Brouns, Thomas M.; Caldwell, Dustin D.; Elliott, Michael L.; Matyas, Josef; Minister, Kevin BC; Schweiger, Michael J.; Strachan, Denis M.; Tinsley, Bronnie P.; Hollenberg, Glenn W.

2005-05-01T23:59:59.000Z

237

Stacker-reclaimer scheduling in a dry bulk terminal  

Science Conference Proceedings (OSTI)

A dry bulk terminal acts as a multi-modal interface for transhipping iron ores. Stacker-reclaimers are the dedicated equipments in storage yard for iron ore handling. Both unloading and loading processes are supported by stacker-reclaimers in most cases. ... Keywords: dry bulk terminal, genetic algorithm, lower bound, stacker-reclaimer scheduling

Dayong Hu; Zhenqiang Yao

2012-11-01T23:59:59.000Z

238

An evolutionary optimization approach for bulk material blending systems  

Science Conference Proceedings (OSTI)

Bulk material blending systems still mostly implement static and non-reactive material blending methods like the well-known Chevron stacking. The optimization potential in the existing systems which can be made available using quality analyzing methods ... Keywords: bulk material blending, chevron stacking, multi-objective evolutionary algorithms

Michael P. Cipold; Pradyumn Kumar Shukla; Claus C. Bachmann; Kaibin Bao; Hartmut Schmeck

2012-09-01T23:59:59.000Z

239

Prediction of Graupel Density in a Bulk Microphysics Scheme  

Science Conference Proceedings (OSTI)

A method to predict the bulk density of graupel ?g has been added to the two-moment Milbrandt–Yau bulk microphysics scheme. The simulation of graupel using the modified scheme is illustrated through idealized simulations of a mesoscale convective ...

Jason A. Milbrandt; Hugh Morrison

2013-02-01T23:59:59.000Z

240

An Empirical Analysis of Bulk Cn2 Models over Water  

Science Conference Proceedings (OSTI)

This article examines some of the difficulties associated with the determination of C2n over water in a coastal region using a bulk model. The analysis shows the need to supplement bulk models with elements that do not belong to traditional Monin–...

Guy Potvin; Denis Dion; Jacques Claverie; Paul A. Frederickson; Kenneth L. Davidson; J. Luc Forand

2008-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Preparation of bulk 13C-enriched graphene materials  

Science Conference Proceedings (OSTI)

Arc-discharge has been widely used in the bulk production of various carbon nanomaterials, especially for structurally more robust single-walled carbon nanotubes. In this paper, the same bulk-production technique was applied to the synthesis of significantly ...

Leilei Tian; Xin Wang; Li Cao; Mohammed J. Meziani; Chang Yi Kong; Fushen Lu; Ya-Ping Sun

2010-01-01T23:59:59.000Z

242

Silicon bulk micromachined hybrid dimensional artifact.  

Science Conference Proceedings (OSTI)

A mesoscale dimensional artifact based on silicon bulk micromachining fabrication has been developed and manufactured with the intention of evaluating the artifact both on a high precision coordinate measuring machine (CMM) and video-probe based measuring systems. This hybrid artifact has features that can be located by both a touch probe and a video probe system with a k=2 uncertainty of 0.4 {micro}m, more than twice as good as a glass reference artifact. We also present evidence that this uncertainty could be lowered to as little as 50 nm (k=2). While video-probe based systems are commonly used to inspect mesoscale mechanical components, a video-probe system's certified accuracy is generally much worse than its repeatability. To solve this problem, an artifact has been developed which can be calibrated using a commercially available high-accuracy tactile system and then be used to calibrate typical production vision-based measurement systems. This allows for error mapping to a higher degree of accuracy than is possible with a glass reference artifact. Details of the designed features and manufacturing process of the hybrid dimensional artifact are given and a comparison of the designed features to the measured features of the manufactured artifact is presented and discussed. Measurement results from vision and touch probe systems are compared and evaluated to determine the capability of the manufactured artifact to serve as a calibration tool for video-probe systems. An uncertainty analysis for calibration of the artifact using a CMM is presented.

Claudet, Andre A.; Tran, Hy D.; Bauer, Todd Marks; Shilling, Katherine Meghan; Oliver, Andrew David

2010-03-01T23:59:59.000Z

243

Bulk Hydrogen Storage - Strategic Directions for Hydrogen Delivery Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

Hydrogen Hydrogen Storage Strategic Directions for Hydrogen Delivery Workshop May 7-8, 2003 Crystal City, Virginia Breakout Session - Bulk Hydrogen Storage Main Themes/Caveats Bulk Storage = Anything not on the vehicle 10's of Tons -- End use point 50-100 Tons - Terminals/City Gates 1000's Tons - Between Production Facility and Terminal/City Gate Bulk storage requirements less restrictive and different from on-board storage Uncertainty about evolution of infrastructure requires multiple pathways to be considered Bulk storage is an economic solution to address supply/demand imbalance Breakout Session - Bulk Hydrogen Storage Targets/Objectives Hard to quantify - scenario & end-use dependent Storage Materials (solid state) and container require different targets

244

Carbon nanotubes grown on bulk materials and methods for fabrication  

DOE Patents (OSTI)

Disclosed are structures formed as bulk support media having carbon nanotubes formed therewith. The bulk support media may comprise fibers or particles and the fibers or particles may be formed from such materials as quartz, carbon, or activated carbon. Metal catalyst species are formed adjacent the surfaces of the bulk support material, and carbon nanotubes are grown adjacent the surfaces of the metal catalyst species. Methods employ metal salt solutions that may comprise iron salts such as iron chloride, aluminum salts such as aluminum chloride, or nickel salts such as nickel chloride. Carbon nanotubes may be separated from the carbon-based bulk support media and the metal catalyst species by using concentrated acids to oxidize the carbon-based bulk support media and the metal catalyst species.

Menchhofer, Paul A. (Clinton, TN); Montgomery, Frederick C. (Oak Ridge, TN); Baker, Frederick S. (Oak Ridge, TN)

2011-11-08T23:59:59.000Z

245

Single event upsets in gallium arsenide pseudo-complementary MESFET logic  

SciTech Connect

An introduction to gallium arsenide (GaAs) Pseudo-Complementary MESFET Logic (PCML) circuits is presented. PCML was developed to reduce the sensitivity of high-speed GaAs logic to radiation-induced single event upsets (SEUs). Experiments for testing the single-event upset (SEU) sensitivity of GaAs PCML integrated circuits (ICs) are described. The results of the experiments are analyzed. This new type of high-speed, low-power, GaAs logic provides decreased sensitivity to SEUs compared to more traditional circuit designs such as Directly-Coupled FET Logic (DCFL). PCML is fully compatible with existing GaAs E/D MESFET fabrication processes, such as those commonly used to make DCFL.

Fouts, D.J.; Wolfe, K.; Van Dyk, S.E. [Naval Postgraduate School, Monterey, CA (United States). Dept. of Electrical and Computer Engineering; Weatherford, T.R. [SFA Inc., Landover, MD (United States); McMorrow, D.; Melinger, J.S.; Tran, L.H.; Campbell, A.B. [Naval Research Lab., Washington, DC (United States)

1995-12-01T23:59:59.000Z

246

Electrical effect of titanium diffusion on amorphous indium gallium zinc oxide  

Science Conference Proceedings (OSTI)

In this work, thermal diffusion phenomenon of Ti into amorphous indium gallium zinc oxide ({alpha}-IGZO) was carefully investigated with secondary ion mass spectroscopy, I-V, and R{sub s} measurement systems and HSC chemistry simulation tool. According to the experimental and simulated results, the diffused Ti atoms were easily oxidized due to its lowest oxidation free energy. Since oxygen atoms were decomposed from the {alpha}-IGZO during the oxidation of Ti, the number of oxygen vacancies working as electron-donating sites in {alpha}-IGZO was dramatically increased, contributing to the decrease of resistivity ({rho}) from 1.96 {Omega} cm (as-deposited {alpha}-IGZO) to 1.33 Multiplication-Sign 10{sup -3}{Omega} cm (350 Degree-Sign C annealed {alpha}-IGZO).

Choi, Seung-Ha [School of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Development Group of Oxide Semiconductor, Samsung Display, Yongin 446-711 (Korea, Republic of); Jung, Woo-Shik [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Park, Jin-Hong [School of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

2012-11-19T23:59:59.000Z

247

Outdoor Performance of a Thin-Film Gallium-Arsenide Photovoltaic Module  

SciTech Connect

We deployed a 855 cm2 thin-film, single-junction gallium arsenide (GaAs) photovoltaic (PV) module outdoors. Due to its fundamentally different cell technology compared to silicon (Si), the module responds differently to outdoor conditions. On average during the test, the GaAs module produced more power when its temperature was higher. We show that its maximum-power temperature coefficient, while actually negative, is several times smaller in magnitude than that of a Si module used for comparison. The positive correlation of power with temperature in GaAs is due to temperature-correlated changes in the incident spectrum. We show that a simple correction based on precipitable water vapor (PWV) brings the photocurrent temperature coefficient into agreement with that measured by other methods and predicted by theory. The low operating temperature and small temperature coefficient of GaAs give it an energy production advantage in warm weather.

Silverman, T. J.; Deceglie, M. G.; Marion, B.; Cowley, S.; Kayes, B.; Kurtz, S.

2013-06-01T23:59:59.000Z

248

Atomistic model of helium bubbles in gallium-stabilized plutonium alloys  

Science Conference Proceedings (OSTI)

The varying thermodynamic stability of gallium- (Ga-) stabilized plutonium (Pu) alloys with temperature affords a unique setting for the development of self-irradiation damage. Here, fundamental characteristics of helium (He) bubbles in these alloys with respect to temperature, gallium concentration, and He-to-vacancy ratio are modeled at the atomistic level with a modified embedded atom potential that takes account of this varying stability. Aside from the bubbles themselves, the surrounding matrix material is single-crystal metal or alloy. As a function of temperature, with a 2:1 He-to-vacancy ratio in a 5-at. % Ga fcc lattice, a 1.25-nm bubble is very stable up to about 1000 K. At 1000 K, the bubble distorts the surrounding lattice and precipitates a liquid zone, as is consistent with the phase diagram for the model material. Between 300 and 500 K, this same bubble relaxes slightly through interstitial emission. At 300 K, with a 2:1 He-to-vacancy ratio in a 2.5-at. % Ga fcc lattice, the Ga stabilization is less effective in the model to the point where the bubble distorts the local lattice and expands significantly. Similarly, at 300 K, if the He-to-vacancy ratio is increased to 3:1, there is significant local lattice distortion, as well as ejection of some He atoms into the lattice. The formation of new bubbles is not observed, because those events take place on a longer time scale than can be simulated with the present approach.

Valone, S. M.; Baskes, M. I. [Materials Science and Technology Division and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Martin, R. L. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2006-06-01T23:59:59.000Z

249

BULK FLOW OF HALOS IN {Lambda}CDM SIMULATION  

Science Conference Proceedings (OSTI)

Analysis of the Pangu N-body simulation validates that the bulk flow of halos follows a Maxwellian distribution with variance that is consistent with the prediction of the linear theory of structure formation. We propose that the consistency between the observed bulk velocity and theories should be examined at the effective scale of the radius of a spherical top-hat window function yielding the same smoothed velocity variance in linear theory as the sample window function does. We compared some recently estimated bulk flows from observational samples with the prediction of the {Lambda}CDM model we used; some results deviate from expectation at a level of {approx}3{sigma}, but the discrepancy is not as severe as previously claimed. We show that bulk flow is only weakly correlated with the dipole of the internal mass distribution, that the alignment angle between the mass dipole and the bulk flow has a broad distribution peaked at {approx}30 Degree-Sign -50 Degree-Sign , and also that the bulk flow shows little dependence on the mass of the halos used in the estimation. In a simulation of box size 1 h {sup -1} Gpc, for a cell of radius 100 h {sup -1} Mpc the maximal bulk velocity is >500 km s{sup -1}; dipoles of the environmental mass outside the cell are not tightly aligned with the bulk flow, but are rather located randomly around it with separation angles {approx}20 Degree-Sign -40 Degree-Sign . In the fastest cell there is a slightly smaller number of low-mass halos; however, halos inside are clustered more strongly at scales {approx}> 20 h {sup -1} Mpc, which might be a significant feature since the correlation between bulk flow and halo clustering actually increases in significance beyond such scales.

Li Ming; Pan Jun; Feng Longlong; Kang Xi [Purple Mountain Observatory, 2 West Beijing Road, Nanjing 210008 (China); Gao Liang [National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012 (China); Jing Yipeng; Yang Xiaohu; Lin Weipeng; Zhao Donghai; Zhang Pengjie [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, 80 Nandan Road, Shanghai 200030 (China); Chi Xuebin; Shan Guihua; Wang Long, E-mail: jpan@bao.ac.cn [Supercomputing Center, Computer Network Information Center, Chinese Academy of Sciences, 4 Zhongguancun Nansijie, Haidian District, Beijing 100190 (China)

2012-12-20T23:59:59.000Z

250

Preparation of copper-indium-gallium-diselenide precursor films by electrodeposition for fabricating high efficiency solar cells  

DOE Patents (OSTI)

A photovoltaic cell exhibiting an overall conversion efficiency of 13.6% is prepared from a copper-indium-gallium-diselenide precursor thin film. The film is fabricated by first simultaneously electrodepositing copper, indium, gallium, and selenium onto a glass/molybdenum substrate (12/14). The electrodeposition voltage is a high frequency AC voltage superimposed upon a DC voltage to improve the morphology and growth rate of the film. The electrodeposition is followed by physical vapor deposition to adjust the final stoichiometry of the thin film to approximately Cu(In.sub.1-n Ga.sub.x)Se.sub.2, with the ratio of Ga/(In+Ga) being approximately 0.39.

Bhattacharya, Raghu N. (Littleton, CO); Hasoon, Falah S. (Arvada, CO); Wiesner, Holm (Golden, CO); Keane, James (Lakewood, CO); Noufi, Rommel (Golden, CO); Ramanathan, Kannan (Golden, CO)

1999-02-16T23:59:59.000Z

251

Brane-Bulk energy exchange and agegraphic dark energy  

E-Print Network (OSTI)

We consider the agegraphic models of dark energy in a braneworld scenario with brane-bulk energy exchange. We assume that the adiabatic equation for the dark matter is satisfied while it is violated for the agegraphic dark energy due to the energy exchange between the brane and the bulk. Our study shows that with the brane-bulk interaction, the equation of state parameter of agegraphic dark energy on the brane, $w_D$, can have a transition from normal state where $w_D >-1 $ to the phantom regime where $w_D energy always satisfies $w^{\\mathrm{eff}}_D\\geq-1$.

Ahmad Sheykhi

2009-08-09T23:59:59.000Z

252

Structural tuning of residual conductivity in highly mismatched III-V layers  

DOE Patents (OSTI)

A new process to control the electrical conductivity of gallium nitride layers grown on a sapphire substrate has been developed. This process is based on initially coating the sapphire substrate with a thin layer of aluminum nitride, then depositing the gallium nitride thereon. This process allows one to controllably produce gallium nitride layers with resistivity varying over as much as 10 orders of magnitude, without requiring the introduction and activation of suitable dopants.

Han, Jung (Albuquerque, NM); Figiel, Jeffrey J. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

253

The design, construction, and testing of a nuclear fuel rod thermal simulation system to study gallium/Zircaloy interactions  

E-Print Network (OSTI)

The presence of gallium in weapons grade plutonium has raised many questions concerning its use in light water reactor (LWR) fuel rods. The biggest concern is that the gallium will migrate down the thermal gradient in the fuel rod and deposit on the inner surface of the clad, which could cause it to fail. In order to study these effects, a fuel rod thermal simulation system (FRTSS) has been developed to recreate the shape and magnitude of the temperature profile in pressurized water reactor (PWR) fuel rods. The system uses electrically heated simulated fuel rods inside of a large, natural convection heat exchanger that uses lead-bismuth eutectic (LBE) (45 <% Pb, 55 <% Bi) as the working fluid. The simulated rods consist of small diameter electric heaters, annular pellets of depleted uranium/cerium oxide doped with approximately 10 ppm of gallium, a small helium filled gap, and generic Zircaloy IV cladding. The system is controlled through a computer-based data acquisition system that is used to record temperature data and operate the various pieces of equipment. A simple mathematical model was used to design the heat exchanger and predict the temperature profile within the simulated rods. Results from system tests indicated that the mathematical model was capable of predicting heater surface temperatures within 6.15% +/- 1.82% and clad outer surface temperatures within 1.91% +/- 4.46%. In addition, the tests also revealed that the system could accurately simulate the temperature profiles of operating PWR fuel rods. Consequently, the FRTSS provides a safe and effective means for studying gallium migration in the fuel pellets and its subsequent interactions with Zircaloy IV.

Allison, Christopher Curtis

1999-01-01T23:59:59.000Z

254

Reference Data for the Density and Viscosity of Liquid Cadmium, Cobalt, Gallium, Indium, Mercury, Silicon, Thallium, and Zinc  

Science Conference Proceedings (OSTI)

The available experimental data for the density and viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc have been critically examined with the intention of establishing both a density and a viscosity standard. All experimental data have been categorized into primary and secondary data according to the quality of measurement, the technique employed and the presentation of the data, as specified by a series of criteria. The proposed standard reference correlations for the density of liquid cadmium, cobalt, gallium, indium, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 0.6, 2.1, 0.4, 0.5, 2.2, 0.9, and 0.7, respectively. In the case of mercury, since density reference values already exist, no further work was carried out. The standard reference correlations for the viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 9.4, 14.0, 13.5, 2.1, 7.3, 15.7, 5.1, and 9.3, respectively.

Assael, Marc J.; Armyra, Ivi J.; Brillo, Juergen; Stankus, Sergei V.; Wu Jiangtao; Wakeham, William A. [Chemical Engineering Department, Aristotle University, 54124 Thessaloniki (Greece); Institut fuer Materialphysik im Weltraum, Deutsches Zentrum fuer Luft- und Raumfahrt, 51170 Koeln (Germany); Kutateladze Institute of Thermophysics, Siberian Brunch of the Russian Academy of Sciences, Lavrentyev ave. 1, 630090 Novosibirsk (Russian Federation); Center of Thermal and Fluid Science, School of Energy and Power Engineering, Xi'an Jiaotong University, Shaanxi 710049 (China); Chemical Engineering Department, Imperial College, London SW7 2BY (United Kingdom)

2012-09-15T23:59:59.000Z

255

Evaluation of critical materials for five advanced design photovoltaic cells with an assessment of indium and gallium  

DOE Green Energy (OSTI)

The objective of this study is to identify potential material supply constraints due to the large-scale deployment of five advanced photovoltaic (PV) cell designs, and to suggest strategies to reduce the impacts of these production capacity limitations and potential future material shortages. This report presents the results of the screening of the five following advanced PV cell designs: polycrystalline silicon, amorphous silicon, cadmium sulfide/copper sulfide frontwall, polycrystalline gallium arsenide MIS, and advanced concentrator-500X. Each of these five cells is screened individually assuming that they first come online in 1991, and that 25 GWe of peak capacity is online by the year 2000. A second computer screening assumes that each cell first comes online in 1991 and that each cell has 5 GWe of peak capacity by the year 2000, so that the total online cpacity for the five cells is 25 GWe. Based on a review of the preliminary basline screening results, suggestions were made for varying such parameters as the layer thickness, cell production processes, etc. The resulting PV cell characterizations were then screened again by the CMAP computer code. Earlier DOE sponsored work on the assessment of critical materials in PV cells conclusively identtified indium and gallium as warranting further investigation as to their availability. Therefore, this report includes a discussion of the future availability of gallium and indium. (WHK)

Watts, R.L.; Gurwell, W.E.; Jamieson, W.M.; Long, L.W.; Pawlewicz, W.T.; Smith, S.A.; Teeter, R.R.

1980-05-01T23:59:59.000Z

256

Modeling Bulk Atmospheric Drainage Flow in a Valley  

Science Conference Proceedings (OSTI)

Most simulations of bulk valley-drainage flows depend heavily on parameterizations. The 1984 Atmospheric Studies in Complex Terrain (ASCOT) field experiment in Brush Creek Valley, Colorado, provided an unprecedented density of measurements in a ...

Ronald J. Dobosy

1989-09-01T23:59:59.000Z

257

ARM - Campaign Instrument - ec-convair580-bulk  

NLE Websites -- All DOE Office Websites (Extended Search)

govInstrumentsec-convair580-bulk govInstrumentsec-convair580-bulk Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign Instrument : Environment Canada Convair 580 Bulk Parameters (EC-CONVAIR580-BULK) Instrument Categories Aerosols, Cloud Properties, Airborne Observations Campaigns Indirect and Semi-Direct Aerosol Campaign (ISDAC) [ Download Data ] North Slope Alaska, 2008.04.01 - 2008.04.30 Primary Measurements Taken The following measurements are those considered scientifically relevant. Refer to the datastream (netcdf) file headers for the list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Ice water content Liquid water content Hydrometeor size Cloud particle number concentration Aerosol concentration

258

Bulk Energy Storage Webinar Rescheduled for February 9, 2012 | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Bulk Energy Storage Webinar Rescheduled for February 9, 2012 Bulk Energy Storage Webinar Rescheduled for February 9, 2012 Bulk Energy Storage Webinar Rescheduled for February 9, 2012 February 1, 2012 - 12:48pm Addthis The U.S. Department of Energy (DOE) and the Iowa Stored Energy Park (ISEP) are conducting a free, 1-hour webinar, Lessons from Iowa: The Economic, Market, and Organizational Issues in Making Bulk Energy Storage Work, on Thursday, February 9, 2012 at 1 p.m. ET. Presenters include Dr. Imre Gyuk of DOE's Office of Electricity Deliverability and Energy Reliability and Bob Schulte from ISEP. The webinar was original scheduled for January 20, 2012, but experienced technical difficulties due to the large number of participants and was rescheduled. All participants must reregister. Funded by a DOE grant and managed by Sandia National Laboratories, ISEP's

259

Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials |  

Office of Science (SC) Website

Design of Bulk Nanocomposites as High Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights Highlight Archives News & Events Publications Contact BES Home 04.27.12 Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials Print Text Size: A A A RSS Feeds FeedbackShare Page Scientific Achievement A newly synthesized bulk thermoelectric material that contains nanocrystals with the same orientation and structure as the host material breaks thermoelectric efficiency records by blocking thermal, but not electrical, conductivity. Significance and Impact A new strategy to design inexpensive materials that more efficiently convert heat to electricity. Research Details Thermoelectric materials directly generate electrical power from heat, but

260

Bodipy-backboned polymers as electron donor in bulk heterojunction ...  

Bodipy-backboned polymers as electron donor in bulk heterojunction solar cellsw BongSoo Kim,a Biwu Ma,*b Venkat R. Donuru,c Haiying Liuc and Jean M. J. Fre´chet*ab

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

A Bulk Microphysics Parameterization with Multiple Ice Precipitation Categories  

Science Conference Proceedings (OSTI)

A single-moment bulk microphysics scheme with multiple ice precipitation categories is described. It has 2 liquid hydrometeor categories (cloud droplets and rain) and 10 ice categories that are characterized by habit, size, and density—two ice ...

Jerry M. Straka; Edward R. Mansell

2005-04-01T23:59:59.000Z

262

Bulk viscosity in nuclear and quark matter: A short review  

E-Print Network (OSTI)

The history and recent progresses in the study of bulk viscosity in nuclear and quark matter are reviewed. The constraints from baryon number conservation and electric neutrality in quark matter on particle densities and fluid velocity divergences are discussed.

Hui Dong; Nan Su; Qun Wang

2007-02-07T23:59:59.000Z

263

Influence of Bulk Convection on Freckle Formation in Castings  

Science Conference Proceedings (OSTI)

compartments, a hot zone and a cold zone as shown in Figure l(a) below. A baffle is used to .... that the bulk convection cell will not distort the flow at the inlet.

264

Mapping the Strain Distributions in Deformed Bulk Metallic Glasses ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Bulk metallic glasses (BMGs) represent relatively new class of ... Evolution of Internal Strain with Temperature in Depleted Uranium in the ... Structural Effects upon Macroscopic Phenomena in Strained Ordered Oxide Films.

265

Development of Bulk Metallic Glasses with High Plasticity Using the ...  

Science Conference Proceedings (OSTI)

Air-Oxidation of a (Zr55Cu30Al10Ni5)98Er2 Bulk Metallic Glass at 350-500oc · Anelastic Deformation of a Metallic Glass · Anisotropy in Metallic Glasses.

266

Photonic integration in a commercial scaled bulk-CMOS process  

E-Print Network (OSTI)

We demonstrate the first photonic chip designed for a commercial bulk CMOS process (65 nm-node) using standard process layers combined with post-processing, enabling dense photonic integration with high-performance ...

Kaertner, Franz X.

267

Structural and economic analysis of capesize bulk carriers  

E-Print Network (OSTI)

Structural failures of bulk carriers continue to account for the loss of many lives every year. Capes are particularly vulnerable to cracking because of their large length, their trade in high density cargos, and the high ...

Hadjiyiannis, Nicholas

2010-01-01T23:59:59.000Z

268

A Second-Order Bulk Boundary-Layer Model  

Science Conference Proceedings (OSTI)

Bulk mass-flux models represent the large eddies that are primarily responsible for the turbulent fluxes in the planetary boundary layer as convective circulations, with an associated convective mass flux. In order for such models to be useful, ...

David A. Randall; Qingqiu Shao; Chin-Hoh Moeng

1992-10-01T23:59:59.000Z

269

South Dakota Gasoline Midgrade Bulk Sales (Volume) by Refiners ...  

U.S. Energy Information Administration (EIA)

South Dakota Gasoline Midgrade Bulk Sales (Volume) by Refiners (Thousand Gallons per Day) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9;

270

HIGH-EFFICIENCY NITRIDE-BASED SOLID-STATE LIGHTING  

SciTech Connect

In this second annual report we summarize the progress in the second-year period of Department of Energy contract DE-FC26-01NT41203, entitled ''High- Efficiency Nitride-Based Solid-State Lighting''. The two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and Rensselaer Polytechnic Institute (led by Dr. N. Narendran), are pursuing the goals of this contract from thin film growth, characterization, and packaging standpoints. The UCSB team has recently made significant progress in the development of light-emitting diodes (LEDs) with AlGaN active regions emitting in the ultraviolet (UV), resonant-cavity LEDs (RCLEDs), as well as lateral epitaxial overgrowth (LEO) techniques to obtain large-area non-polar GaN films with low average dislocation density. The Rensselaer team has benchmarked the performance of commercially available LED systems and has also conducted efforts to develop an optimized RCLED packaging scheme, including development of advanced epoxy encapsulant chemistries.

Paul T. Fini; Shuji Nakamura

2003-10-30T23:59:59.000Z

271

Radial elasticity of multi-walled boron nitride nanotubes  

Science Conference Proceedings (OSTI)

We investigated the radial mechanical properties of multi-walled boron nitride nanotubes (MW-BNNTs) using atomic force microscopy. The employed MW-BNNTs were synthesized using pressurized vapor/condenser (PVC) methods and were dispersed in aqueous solution using ultrasonication methods with the aid of ionic surfactants. Our nanomechanical measurements reveal the elastic deformational behaviors of individual BNNTs with two to four tube walls in their transverse directions. Their effective radial elastic moduli were obtained through interpreting their measured radial deformation profiles using Hertzian contact mechanics models. Our results capture the dependences of the effective radial moduli of MW-BNNTs on both the tube outer diameter and the number of tube layers. The effective radial moduli of double-walled BNNTs are found to be several-fold higher than those of single-walled BNNTs within the same diameter range. Our work contributes directly to a complete understanding of the fundamental structural and mechanical properties of BNNTs and the pursuits of their novel structural and electronics applications.

Michael W. Smith, Cheol Park, Meng Zheng, Changhong Ke ,In-Tae Bae, Kevin Jordan

2012-02-01T23:59:59.000Z

272

Excitation wavelength dependence of water-window line emissions from boron-nitride laser-produced plasmas  

E-Print Network (OSTI)

Excitation wavelength dependence of water-window line emissions from boron-nitride laser-produced of laser excitation wavelength on water-window emission lines of laser- produced boron-nitride plasmas. Plasmas are produced by focusing 1064 nm and harmonically generated 532 and 266 nm radiation from a Nd

Harilal, S. S.

273

Compositional ordering and stability in nanostructured, bulk thermoelectric alloys.  

SciTech Connect

Thermoelectric materials have many applications in the conversion of thermal energy to electrical power and in solid-state cooling. One route to improving thermoelectric energy conversion efficiency in bulk material is to embed nanoscale inclusions. This report summarize key results from a recently completed LDRD project exploring the science underpinning the formation and stability of nanostructures in bulk thermoelectric and the quantitative relationships between such structures and thermoelectric properties.

Hekmaty, Michelle A.; Faleev, S.; Medlin, Douglas L.; Leonard, F.; Lensch-Falk, J.; Sharma, Peter Anand; Sugar, J. D.

2009-09-01T23:59:59.000Z

274

Bulk viscosity and the conformal anomaly in the pion gas  

E-Print Network (OSTI)

We calculate the bulk viscosity of the massive pion gas within Unitarized Chiral Perturbation Theory. We obtain a low temperature peak arising from explicit conformal breaking due to the pion mass and another peak near the critical temperature, dominated by the conformal anomaly through gluon condensate terms. The correlation between bulk viscosity and conformal breaking supports a recent QCD proposal. We discuss the role of resonances, heavier states and large-$N_c$ counting.

D. Fernandez-Fraile; A. Gomez Nicola

2008-09-26T23:59:59.000Z

275

Finsler geometric perspective on the bulk flow in the universe  

E-Print Network (OSTI)

Astronomical observations showed that there may exist a bulk flow with peculiar velocities in the universe, which contradicts with the (\\Lambda)CDM model. The bulk flow reveals that the observational universe is anisotropic at large scales. In fact, a more reliable observation on the anisotropy of spacetime comes from the CMB power spectra. The WMAP and Planck satellites both show that there is a hemispherical power asymmetry at large-angular scales. In this paper, we propose a "wind" scenario to the bulk flow (or the anisotropy of spacetime). Under the influence of the "wind", the spacetime metric could become a Finsler structure. By resolving the null geodesic equation, we obtain the modified luminosity distance, which has a dipolar form at the leading order. Thus, the "wind" describes well the bulk flow. In addition, we perform a least-(\\chi^2) fit to the data of type Ia supernovae (SNe Ia) in the Union2.1 compilation. The peculiar velocity of the bulk flow has an upper limit (v_{bulk}\\lesssim 4000 \\rm{km/s}), which is compatible with all the existing observational values.

Zhe Chang; Ming-Hua Li; Sai Wang

2013-03-07T23:59:59.000Z

276

Synthesis of fine-grained .alpha.-silicon nitride by a combustion process  

DOE Patents (OSTI)

A combustion synthesis process for the preparation of .alpha.-silicon nitride and composites thereof is disclosed. Preparation of the .alpha.-silicon nitride comprises the steps of dry mixing silicon powder with an alkali metal azide, such as sodium azide, cold-pressing the mixture into any desired shape, or loading the mixture into a fused, quartz crucible, loading the crucible into a combustion chamber, pressurizing the chamber with nitrogen and igniting the mixture using an igniter pellet. The method for the preparation of the composites comprises dry mixing silicon powder (Si) or SiO.sub.2, with a metal or metal oxide, adding a small amount of an alkali metal azide such as sodium azide, introducing the mixture into a suitable combustion chamber, pressurizing the combustion chamber with nitrogen, igniting the mixture within the combustion chamber, and isolating the .alpha.-silicon nitride formed as a reaction product.

Holt, J. Birch (San Jose, CA); Kingman, Donald D. (Danville, CA); Bianchini, Gregory M. (Livermore, CA)

1990-01-01T23:59:59.000Z

277

A Probabilistic Bulk Model of Coupled Mixed Layer and Convection. Part I: Clear-Sky Case  

Science Conference Proceedings (OSTI)

A new bulk model of the convective boundary layer, the probabilistic bulk convection model (PBCM), is presented. Unlike prior bulk approaches that have modeled the mixed-layer-top buoyancy flux as a constant fraction of the surface buoyancy flux, ...

Pierre Gentine; Alan K. Betts; Benjamin R. Lintner; Kirsten L. Findell; Chiel C. van Heerwaarden; Alexandra Tzella; Fabio D’Andrea

2013-06-01T23:59:59.000Z

278

Novel Approaches to High-Efficiency III-V Nitride Heterostructure Emitters for Next-Generation Lighting Applications  

SciTech Connect

We report research activities and technical progress on the development of high-efficiency long wavelength ({lambda} {approx} 540nm) green light emitting diodes which covers whole years of the three-year program 'Novel approaches to high-efficiency III-V nitride heterostructure emitters for next-generation lighting applications'. The research activities were focused on the development of p-type layer that has less/no detrimental thermal annealing effect on as well as excellent structural and electrical properties and the development of green LED active region that has superior luminescence quality for {lambda}{approx}540nm green LEDs. We have also studied (1) the thermal annealing effect on blue and green LED active region during the p-type layer growth; (2) the effect of growth parameters and structural factors for LED active region on electroluminescence properties; (3) the effect of substrates and orientation on electrical and electro-optical properties of green LEDs. As a progress highlight, we obtained green-LED-active-region-friendly In{sub 0.04}Ga{sub 0.96}N:Mg exhibiting low resistivity with higher hole concentration (p=2.0 x 10{sup 18} cm{sup -3} and a low resistivity of 0.5 {omega}-cm) and improved optical quality green LED active region emitting at {approx}540nm by electroluminescence. The LEDs with p-InGaN layer can act as a quantum-confined Stark effect mitigation layer by reducing strain in the QW. We also have achieved (projected) peak IQE of {approx}25% at {lambda}{approx}530 nm and of {approx}13% at {lambda}{approx}545 nm. Visible LEDs on a non-polar substrate using (11-20) {alpha}-plane bulk substrates. The absence of quantum-confined Stark effect was confirmed but further improvement in electrical and optical properties is required.

Russell Dupuis

2007-06-30T23:59:59.000Z

279

Novel Approaches to High-Efficiency III-V Nitride Heterostructure Emitters for Next-Generation Lighting Applications  

SciTech Connect

We report research activities and technical progress on the development of high-efficiency long wavelength ({lambda} {approx} 540nm) green light emitting diodes which covers whole years of the three-year program 'Novel approaches to high-efficiency III-V nitride heterostructure emitters for next-generation lighting applications'. The research activities were focused on the development of p-type layer that has less/no detrimental thermal annealing effect on as well as excellent structural and electrical properties and the development of green LED active region that has superior luminescence quality for {lambda}{approx}540nm green LEDs. We have also studied (1) the thermal annealing effect on blue and green LED active region during the p-type layer growth; (2) the effect of growth parameters and structural factors for LED active region on electroluminescence properties; (3) the effect of substrates and orientation on electrical and electro-optical properties of green LEDs. As a progress highlight, we obtained green-LED-active-region-friendly In{sub 0.04}Ga{sub 0.96}N:Mg exhibiting low resistivity with higher hole concentration (p=2.0 x 10{sup 18} cm{sup -3} and a low resistivity of 0.5 {omega}-cm) and improved optical quality green LED active region emitting at {approx}540nm by electroluminescence. The LEDs with p-InGaN layer can act as a quantum-confined Stark effect mitigation layer by reducing strain in the QW. We also have achieved (projected) peak IQE of {approx}25% at {lambda}{approx}530 nm and of {approx}13% at {lambda}{approx}545 nm. Visible LEDs on a non-polar substrate using (11-20) {alpha}-plane bulk substrates. The absence of quantum-confined Stark effect was confirmed but further improvement in electrical and optical properties is required.

Russell Dupuis

2007-06-30T23:59:59.000Z

280

Alternative Liquid Fuel Effects on Cooled Silicon Nitride Marine Gas Turbine Airfoils  

Science Conference Proceedings (OSTI)

With prior support from the Office of Naval Research, DARPA, and U.S. Department of Energy, United Technologies is developing and engine environment testing what we believe to be the first internally cooled silicon nitride ceramic turbine vane in the United States. The vanes are being developed for the FT8, an aeroderivative stationary/marine gas turbine. The current effort resulted in further manufacturing and development and prototyping by two U.S. based gas turbine grade silicon nitride component manufacturers, preliminary development of both alumina, and YTRIA based environmental barrier coatings (EBC's) and testing or ceramic vanes with an EBC coating.

Holowczak, J.

2002-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical...  

NLE Websites -- All DOE Office Websites (Extended Search)

Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical Investigation Solar Cells: Spin-Cast Bulk Heterojunction Solar Cells: A Dynamical Investigation Print Wednesday,...

282

Induction, helicity, and alpha effect in a toroidal screw flow of liquid gallium  

SciTech Connect

We investigate experimentally induction mechanisms in a screw flow of gallium in a toroidal channel. The flow is nonstationary and operated in a spin-down regime: the channel (and fluid) are initially set into solid body rotation; as the channel is stopped the fluid is set into strong helical motion by diverters located inside the channel. In this study, we put a particular emphasis on the induction generated by these helical motions, which are expected to develop over the entire range of turbulent scales. We apply an external magnetic field either perpendicular to the channel axis parallel to it. At large scales the nonlinear induction mechanisms are associated with the Parker stretch and twist effect and with the expulsion due to overall rotation. Induction mechanisms can also originate in the small scale helicity as in the alpha induction effect of mean-field magnetohydrodynamics. Our measurements yield an upper bound for the alpha coefficient, significantly lower than estimates based on dimensional analysis. We discuss the consequences of our observations for the engineering of homogeneous dynamos in the laboratory.

Stepanov, R.; Denisov, S.; Noskov, V. [Institute of Continuous Media MechanicsKorolyov 1, 614061 Perm (Russian Federation); Volk, R.; Frick, P.; Pinton, J.-F. [Laboratoire de Physique de l'Ecole Normale Superieur de Lyon, CNRS UMR5672, 46 allee d'Italie, 69007 Lyon (France)

2006-04-15T23:59:59.000Z

283

Surface Composition, Work Function, and Electrochemical Characteristics of Gallium-Doped Zinc Oxide  

Science Conference Proceedings (OSTI)

Gallium-doped zinc oxide (GZO) possesses the electric conductivity, thermal stability, and earth abundance to be a promising transparent conductive oxide replacement for indium tin oxide electrodes in a number of molecular electronic devices, including organic solar cells and organic light emitting diodes. The surface chemistry of GZO is complex and dominated by the hydrolysis chemistry of ZnO, which influences the work function via charge transfer and band bending caused by adsorbates. A comprehensive characterization of the surface chemical composition and electrochemical properties of GZO electrodes is presented, using both solution and surface adsorbed redox probe molecules. The GZO surface is characterized using monochromatic X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy after the following pretreatments: (i) hydriodic acid etch, (ii) potassium hydroxide etch, (iii) RF oxygen plasma etching, and (iv) high-vacuum argon-ion sputtering. The O 1s spectra for the GZO electrodes have contributions from the stoichiometric oxide lattice, defects within the lattice, hydroxylated species, and carbonaceous impurities, with relative near-surface compositions varying with pretreatment. Solution etching procedures result in an increase of the work function and ionization potential of the GZO electrode, but yield different near surface Zn:Ga atomic ratios, which significantly influence charge transfer rates for a chemisorbed probe molecule. The near surface chemical composition is shown to be the dominant factor in controlling surface work function and significantly influences the rate of electron transfer to both solution and tethered probe molecules.

Ratcliff, E. L.; Sigdel, A. K.; Macech, M. R.; Nebesny, K.; Lee, P. A.; Ginley, D. S.; Armstrong, N. R.; Berry, J. J.

2012-06-30T23:59:59.000Z

284

CX-000845: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

0845: Categorical Exclusion Determination 0845: Categorical Exclusion Determination CX-000845: Categorical Exclusion Determination 25A2445 - Ammonothermal Bulk Gallium Nitride (GaN) Crystal Growth for Energy Efficient Lighting CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): New York Office(s): Advanced Research Projects Agency - Energy This project plans to address the vast energy loss and consumption associated with conventional lighting by developing a new route to large, high-quality, single crystals of gallium nitride. These crystals will serve as substrates for light emitting diodes offering high-efficiency lighting. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-000845.pdf More Documents & Publications CX-009889: Categorical Exclusion Determination Power Electronics Research and Development Program Plan

285

The Influence of Lewis Acid/Base Chemistry on the Removal of Gallium by Volatility from Weapons-Grade Plutonium Dissolved in Molten Chlorides  

Science Conference Proceedings (OSTI)

It has been proposed that GaCl{sub 3} can be removed by direct volatilization from a Pu-Ga alloy that is dissolved in a molten chloride salt. Although pure GaCl{sub 3} is quite volatile (boiling point: 201 deg. C), the behavior of GaCl{sub 3} dissolved in chloride salts is quite different because of solution effects and is critically dependent upon the composition of the solvent salt (i.e., its Lewis acid/base character). In this technical note, the behavior of gallium in prototypical Lewis acid and Lewis base salts is contrasted. It is found that gallium volatility is suppressed in basic melts and promoted in acidic melts. These results have an important influence on the potential for simple gallium removal in molten salt systems.

Williams, David F.; Cul, Guillermo D. del [Oak Ridge National Laboratory (United States); Toth, Louis M. [Electrochemical Systems (United States); Collins, Emory D. [Oak Ridge National Laboratory (United States)

2001-12-15T23:59:59.000Z

286

The Interfacial Mechanics of the Thin Oxide Skin on Liquid Gallium ...  

Science Conference Proceedings (OSTI)

The ability to micromold the metal for these applications is enabled by the ... The oxide skin is elastic and yields under a critical stress, at which point the metal flows. ... Interface Bond Strength of HIP-Clad Depleted Uranium and 6061- Aluminum ... Quantitative NanoSIMS Analysis of Grain Boundary Segregation in Bulk ...

287

High Accuracy Predictions of the Bulk Properties of Water | Argonne  

NLE Websites -- All DOE Office Websites (Extended Search)

High Accuracy Predictions of the Bulk Properties of Water High Accuracy Predictions of the Bulk Properties of Water High Accuracy Predictions of the Bulk Properties of Water PI Name: Mark Gordon PI Email: mark@si.msg.chem.iastate.edu Institution: Iowa State University Allocation Program: ESP Allocation Hours at ALCF: 150 Million Year: 2010 to 2013 Research Domain: Chemistry Among the ab initio methods, second-order perturbation theory (MP2) predicts highly accurate structures and relative energies for water clusters. Researchers will carry out molecular dynamics simulations of water at the MP2 level. However, full MP2 calculations of even modest-sized water clusters are far too time-consuming for dynamical simulations, even on the next-generation Blue Gene. Therefore, a key element of the current approach will be the use of MP2 in conjunction with the Fragment Molecular

288

Phantom dark energy as an effect of bulk viscosity  

E-Print Network (OSTI)

In a homogeneous and isotropic universe bulk viscosity is the unique viscous effect capable to modify the background dynamics. Effects like shear viscosity or heat conduction can only change the evolution of the perturbations. The existence of a bulk viscous pressure in a fluid, which in order to obey to the second law of thermodynamics is negative, reduces its effective pressure. We discuss in this study the degeneracy in bulk viscous cosmologies and address the possibility that phantom dark energy cosmology could be caused by the existence of non-equilibrium pressure in any cosmic component. We establish the conditions under which either matter or radiation viscous cosmologies can be mapped into the phantom dark energy scenario with constraints from multiple observational data-sets

Hermano Velten; Jiaxin Wang; Xinhe Meng

2013-07-16T23:59:59.000Z

289

Properties of Bulk Sintered Silver As a Function of Porosity  

SciTech Connect

This report summarizes a study where various properties of bulk-sintered silver were investigated over a range of porosity. This work was conducted within the National Transportation Research Center's Power Device Packaging project that is part of the DOE Vehicle Technologies Advanced Power Electronics and Electric Motors Program. Sintered silver, as an interconnect material in power electronics, inherently has porosity in its produced structure because of the way it is made. Therefore, interest existed in this study to examine if that porosity affected electrical properties, thermal properties, and mechanical properties because any dependencies could affect the intended function (e.g., thermal transfer, mechanical stress relief, etc.) or reliability of that interconnect layer and alter how its performance is modeled. Disks of bulk-sintered silver were fabricated using different starting silver pastes and different sintering conditions to promote different amounts of porosity. Test coupons were harvested out of the disks to measure electrical resistivity and electrical conductivity, thermal conductivity, coefficient of thermal expansion, elastic modulus, Poisson's ratio, and yield stress. The authors fully recognize that the microstructure of processed bulk silver coupons may indeed not be identical to the microstructure produced in thin (20-50 microns) layers of sintered silver. However, measuring these same properties with such a thin actual structure is very difficult, requires very specialized specimen preparation and unique testing instrumentation, is expensive, and has experimental shortfalls of its own, so the authors concluded that the herein measured responses using processed bulk sintered silver coupons would be sufficient to determine acceptable values of those properties. Almost all the investigated properties of bulk sintered silver changed with porosity content within a range of 3-38% porosity. Electrical resistivity, electrical conductivity, thermal conductivity, elastic modulus, Poisson's ratio, and yield stress all depended on the porosity content in bulk-sintered silver. The only investigated property that was independent of porosity in that range was coefficient of thermal expansion.

Wereszczak, Andrew A [ORNL; Vuono, Daniel J [ORNL; Wang, Hsin [ORNL; Ferber, Mattison K [ORNL; Liang, Zhenxian [ORNL

2012-06-01T23:59:59.000Z

290

Physical factors controlling the ductility of bulk metallic glasses  

SciTech Connect

In order to identify key physical factor controlling the deformation and fracture behavior of bulk metallic glasses (BMGs), we compiled and analyzed the elastic moduli and compressive ductility for BMGs. In addition, new modulus data were generated in the critical ranges in order to facilitate the analysis. We have found that the intrinsic ductility of BMGs can be correlated with the bulk-to-shear modulus ratio B/G according to Pugh's [Philos. Mag. 45, 823 (1954) ] rule. In some individual BMG systems, for example, Fe based, the relationship seems to be very clear. The physical meaning of this correlation is discussed in terms of atomic bonding and connectivity.

Liu, Y. [Central South University, China; Liu, Chain T [ORNL; Zhang, Z. [University of Tennessee, Knoxville (UTK); Keppens, V. [University of Tennessee, Knoxville (UTK)

2008-01-01T23:59:59.000Z

291

Nucleation of bulk superconductivity close to critical magnetic field  

E-Print Network (OSTI)

We consider the two-dimensional Ginzburg-Landau functional with constant applied magnetic field. For applied magnetic fields close to the second critical field $H_{C_2}$ and large Ginzburg-Landau parameter, we provide leading order estimates on the energy of minimizing configurations. We obtain a fine threshold value of the applied magnetic field for which bulk superconductivity contributes to the leading order of the energy. Furthermore, the energy of the bulk is related to that of the Abrikosov problem in a periodic lattice. A key ingredient of the proof is a novel $L^\\infty$-bound which is of independent interest.

S. Fournais; A. Kachmar

2009-09-30T23:59:59.000Z

292

Method of chemical vapor deposition of boron nitride using polymeric cyanoborane  

DOE Patents (OSTI)

Polymeric cyanoborane is volatilized, decomposed by thermal or microwave plasma energy, and deposited on a substrate as an amorphous film containing boron, nitrogen and carbon. Residual carbon present in the film is removed by ammonia treatment at an increased temperature, producing an adherent, essentially stoichiometric boron nitride film.

Maya, Leon (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

293

Hands-On Session 6: Monolayer Boron Nitride BerkeleyGW Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

Hands-On Session 6: Monolayer Boron Nitride Hands-On Session 6: Monolayer Boron Nitride BerkeleyGW Workshop 11/23/2013 Diana Qiu Goals: 1. Demonstrate a GW-BSE calculation for a 2D semiconductor 2. Look at the behavior of ε -1 00 (q) for a system with a truncated Coulomb interaction 3. Learn how to use BerkeleyGW's visualization tools to look at the exciton wave function Instructions: Please copy the example directory into your scratch directory >> cp -rP /project/projectdirs/m1694/BGW-2013/6-boron_nitride $SCRATCH/ 1-MF ● Please go the directory ``6-boron_nitride/1-mf/`` ● Enter each directory in numerical order and follow the instructions in the README files. Some things to note for 2D calculations: ● The system is in a periodic supercell. Though we will not do so in this calculation, you should always converge the k-grid sampling and amount of vacuum between

294

Silicon-doped boron nitride coated fibers in silicon melt infiltrated composites  

SciTech Connect

A fiber-reinforced silicon-silicon carbide matrix composite having improved oxidation resistance at high temperatures in dry or water-containing environments is produced. The invention also provides a method for protecting the reinforcing fibers in the silicon-silicon carbide matrix composites by coating the fibers with a silicon-doped boron nitride coating.

Corman, Gregory Scot (Ballston Lake, NY); Luthra, Krishan Lal (Schenectady, NY)

2002-01-01T23:59:59.000Z

295

Silicon-doped boron nitride coated fibers in silicon melt infiltrated composites  

SciTech Connect

A fiber-reinforced silicon--silicon carbide matrix composite having improved oxidation resistance at high temperatures in dry or water-containing environments is produced. The invention also provides a method for protecting the reinforcing fibers in the silicon--silicon carbide matrix composites by coating the fibers with a silicon-doped boron nitride coating.

Corman, Gregory Scot (Ballston Lake, NY); Luthra, Krishan Lal (Schenectady, NY)

1999-01-01T23:59:59.000Z

296

Silicon-doped boron nitride coated fibers in silicon melt infiltrated composites  

SciTech Connect

A fiber-reinforced silicon-silicon carbide matrix composite having improved oxidation resistance at high temperatures in dry or water-containing environments is produced. The invention also provides a method for protecting the reinforcing fibers in the silicon-silicon carbide matrix composites by coating the fibers with a silicon-doped boron nitride coating.

Corman, G.S.; Luthra, K.L.

1999-09-14T23:59:59.000Z

297

Bonding in hard and elastic amorphous carbon nitride films investigated H NMR spectroscopy  

E-Print Network (OSTI)

Bonding in hard and elastic amorphous carbon nitride films investigated using 15 N, 13 C, and 1 H Received 14 February 2003; published 5 November 2003 The nitrogen bonding in hard and elastic amorphous substrates at 300 °C. Nanoindentation tests revealed an elastic recovery of 80%, a hardness of 5 GPa

Reilly, Anne

298

Sintered Reaction Bonded Silicon Parts by Microwave Nitridation Combined with Gas-Pressure Sintering  

DOE Green Energy (OSTI)

The cooperative project was a joint development program between Ceradyne and Oak Ridge National Laboratory through Lockheed Martin Energy Research (LMER). Cooperative work was of benefit to both parties. ORNL was able to assess the effect of the microwave nitridation process coupled with gas-pressure sintering for fabrication of parts for advanced diesel engines. Ceradyne gained access to gelcasting expertise and microwave facilities and experience for the nitridation of SRBSN materials. The broad objective of the CRADA between Ceradyne and OIWL was to (1) examine the applicability of the gelcasting technology to fabricate parts from SRBSN, and (2) to assess the effect of the microwave nitridation of silicon process coupled with gas-pressure sintering for fabrication of parts for advanced diesel engines. The following conclusions can be made from the work performed under the CRADA: (1) Gelcasting is a viable method to fabricate SRBSN parts using Ceradyne Si mixtures. However, the technique requires further development prior to being put into commercial use. (2) Microwave heating can be utilized to nitride multiple SRBSN parts. Scale-up of the process to fabricate several kilograms of material (up to 6 kg) per furnace run was demonstrated.

Kiggans, J.O.; Mikijelj, B.; Tiegs, T.N.

1999-01-01T23:59:59.000Z

299

Evaluation and silicon nitride internal combustion engine components. Final report, Phase I  

DOE Green Energy (OSTI)

The feasibility of silicon nitride (Si{sub 3}N{sub 4}) use in internal combustion engines was studied by testing three different components for wear resistance and lower reciprocating mass. The information obtained from these preliminary spin rig and engine tests indicates several design changes are necessary to survive high-stress engine applications. The three silicon nitride components tested were valve spring retainers, tappet rollers, and fuel pump push rod ends. Garrett Ceramic Components` gas-pressure sinterable Si{sub 3}N{sub 4} (GS-44) was used to fabricate the above components. Components were final machined from densified blanks that had been green formed by isostatic pressing of GS-44 granules. Spin rig testing of the valve spring retainers indicated that these Si{sub 3}N{sub 4} components could survive at high RPM levels (9,500) when teamed with silicon nitride valves and lower spring tension than standard titanium components. Silicon nitride tappet rollers showed no wear on roller O.D. or I.D. surfaces, steel axles and lifters; however, due to the uncrowned design of these particular rollers the cam lobes indicated wear after spin rig testing. Fuel pump push rod ends were successful at reducing wear on the cam lobe and rod end when tested on spin rigs and in real-world race applications.

Voldrich, W. [Allied-Signal Aerospace Co., Torrance, CA (United States). Garrett Ceramic Components Div.

1992-04-01T23:59:59.000Z

300

Compatibility/Stability Issues in the Use of Nitride Kernels in LWR TRISO Fuel  

SciTech Connect

The stability of the SiC layer in the presence of free nitrogen will be dependent upon the operating temperatures and resulting nitrogen pressures whether it is at High Temperature Gas-Cooled Reactor (HTGR) temperatures of 1000-1400 C (coolant design dependent) or LWR temperatures that range from 500-700 C. Although nitrogen released in fissioning will form fission product nitrides, there will remain an overpressure of nitrogen of some magnitude. The nitrogen can be speculated to transport through the inner pyrolytic carbon layer and contact the SiC layer. The SiC layer may be envisioned to fail due to resulting nitridation at the elevated temperatures. However, it is believed that these issues are particularly avoided in the LWR application. Lower temperatures will result in significantly lower nitrogen pressures. Lower temperatures will also substantially reduce nitrogen diffusion rates through the layers and nitriding kinetics. Kinetics calculations were performed using an expression for nitriding silicon. In order to further address these concerns, experiments were run with surrogate fuel particles under simulated operating conditions to determine the resulting phase formation at 700 and 1400 C.

Armstrong, Beth L [ORNL; Besmann, Theodore M [ORNL

2012-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Method of chemical vapor deposition of boron nitride using polymeric cyanoborane  

DOE Patents (OSTI)

Polymeric cyanoborane is volatilized, decomposed by thermal or microwave plasma energy, and deposited on a substrate as an amorphous film containing boron, nitrogen and carbon. Residual carbon present in the film is removed by ammonia treatment at an increased temperature, producing an adherent, essentially stoichiometric boron nitride film. 11 figs.

Maya, L.

1994-06-14T23:59:59.000Z

302

PION CONDENSATION IN A FIELD THEORY CONSISTENT WITH BULK PROPERTIES OF NUCLEAR MATTER  

E-Print Network (OSTI)

theory is constrained to reproduce the known bulk properties of nuclear matter, namely its saturation energy,

Banerjee, B.

2013-01-01T23:59:59.000Z

303

Effect of Varying Bulk Viscosity on Generalized Chaplygin Gas  

E-Print Network (OSTI)

In this paper, viscous generalized Chaplygin gas as a model of dark energy considered. We assume non-constant bulk viscous coefficient and study dark energy density. We consider several cases of density-dependent viscosities. We find that, in the special case, the viscous generalized Chaplygin gas is corresponding to modified Chaplygin gas.

Saadat, H

2013-01-01T23:59:59.000Z

304

Effect of Varying Bulk Viscosity on Generalized Chaplygin Gas  

E-Print Network (OSTI)

In this paper, viscous generalized Chaplygin gas as a model of dark energy considered. We assume non-constant bulk viscous coefficient and study dark energy density. We consider several cases of density-dependent viscosities. We find that, in the special case, the viscous generalized Chaplygin gas is corresponding to modified Chaplygin gas.

H. Saadat; B. Pourhassan

2013-05-26T23:59:59.000Z

305

A Warm-Bin–Cold-Bulk Hybrid Cloud Microphysical Model  

Science Conference Proceedings (OSTI)

This study describes a newly developed bin–bulk hybrid cloud microphysical model named MSSG-Bin, which has been implemented in the Multi-Scale Simulator for the Geoenvironment (MSSG). In the hybrid approach, a spectral bin scheme is used for ...

Ryo Onishi; Keiko Takahashi

2012-05-01T23:59:59.000Z

306

ENVIRONMENTAL BIOTECHNOLOGY Effect of bulk liquid BOD concentration on activity  

E-Print Network (OSTI)

to assess the impact of bulk liquid biological oxygen demand (BOD) concentrations on the activity oxygen demand (BOD) for denitrification, are critical for improving current wastewater treatment and Geological Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, IN 46556, USA e

Nerenberg, Robert

307

Approximating Buy-at-Bulk k-Steiner trees  

E-Print Network (OSTI)

In the buy-at-bulk $k$-Steiner tree (or rent-or-buy$k$-Steiner tree) problem we are given a graph $G(V,E)$ with a setof terminals $T\\subseteq V$ including a particular vertex $s$ calledthe root, and an integer $k\\leq |T|$. ...

Hajiaghayi, MohammadTaghi

2005-11-15T23:59:59.000Z

308

Experiences with bulk SMS for health financing in Uganda  

Science Conference Proceedings (OSTI)

Short message service (SMS, aka text messaging) is a low-cost and effective means of communication for organizations attempting to maintain contact with many people. In this paper we look at the deployment and of a bulk mobile text-messaging platform ... Keywords: braided communications, bulksms, health, ictd, mobile phone, sms

Melissa Densmore

2012-05-01T23:59:59.000Z

309

Security-Constrained Adequacy Evaluation of Bulk Power System Reliability  

E-Print Network (OSTI)

Security-Constrained Adequacy Evaluation of Bulk Power System Reliability Fang Yang, Student Member. Stefopoulos, Student Member, IEEE Abstract -- A framework of security-constrained adequacy evaluation (SCAE electric load while satisfying security constraints. It encompasses three main steps: (a) critical

310

A COMPREHENSIVE TECHNICAL REVIEW OF THE DEMONSTRATION BULK VITRIFICATION SYSTEM  

Science Conference Proceedings (OSTI)

In May 2006, CH2M Hill Hanford Group, Inc. chartered an Expert Review Panel (ERP) to review the current status of the Demonstration Bulk Vitrification System (DBVS). It is the consensus of the ERP that bulk vitrification is a technology that requires further development and evaluation to determine its potential for meeting the Hanford waste stabilization mission. No fatal flaws (issues that would jeopardize the overall DBVS mission that cannot be mitigated) were found, given the current state of the project. However, a number of technical issues were found that could significantly affect the project's ability to meet its overall mission as stated in the project ''Justification of Mission Need'' document, if not satisfactorily resolved. The ERP recognizes that the project has changed from an accelerated schedule demonstration project to a formally chartered project that must be in full compliance with DOE 413.3 requirements. The perspective of the ERP presented herein, is measured against the formally chartered project as stated in the approved Justification of Mission Need document. A justification of Mission Need document was approved in July 2006 which defined the objectives for the DBVS Project. In this document, DOE concluded that bulk vitrification is a viable technology that requires additional development to determine its potential applicability to treatment of a portion of the Hanford low activity waste. The DBVS mission need statement now includes the following primary objectives: (1) process approximately 190,000 gallons of Tank S-109 waste into fifty 100 metric ton boxes of vitrified product; (2) store and dispose of these boxes at Hanford's Integrated Disposal Facility (IDF); (3) evaluate the waste form characteristics; (4) gather pilot plant operability data, and (5) develop the overall life cycle system performance of bulk vitrification and produce a comparison of the bulk vitrification process to building a second LAW Immobilization facility or other supplemental treatment alternatives as provided in M-62-08.

SCHAUS, P.S.

2006-09-29T23:59:59.000Z

311

Comparison of Cavitation-Erosion Resistance of Carburized and Carburized-Plus-Nitrided 316LN Stainless Steel in Mercury  

SciTech Connect

Annealed type 316LN stainless steel in the (1) carburized and the (2) carburized plus nitrided conditions was evaluated for cavitation-erosion resistance in ambient temperature mercury using a vibratory horn method. The results indicated that, relative to the specimens receiving only the carburizing treatment, the specimens that received both surface treatments exhibited substantially greater weight loss, general thinning, and profile development as a function of sonication time - with all observed degradation limited to the nitrided layer. Further, the nitride layer was observed to be susceptible to extensive cracking (occasionally leading to spallation), but the cracking was never observed to penetrate into the carburized layer. These screening test results suggest there is no improvement in cavitation-erosion resistance associated with augmentation of the carburizing treatment with plasma nitriding.

Pawel, Steven J [ORNL

2007-05-01T23:59:59.000Z

312

Aluminum nitride transitional layer for reducing dislocation density and cracking of AlGaN epitaxial films  

DOE Patents (OSTI)

A denticulated Group III nitride structure that is useful for growing Al.sub.xGa.sub.1-xN to greater thicknesses without cracking and with a greatly reduced threading dislocation (TD) density.

Allerman, Andrew A.; Crawford, Mary H.; Lee, Stephen R.

2013-01-08T23:59:59.000Z

313

Nuclear fuels technologies: Thermally induced gallium removal system (TIGRS), fiscal year 1998 research and development test plan  

SciTech Connect

This document details the research and development (R and D) activities that will be conducted in Fiscal Year 1998 (FY98) by the Thermally Induced Gallium Removal System (TIGRS) team for the Department of Energy Office of Fissile Materials Disposition. This work is a continuation and extension of experimental activities that have been conducted in support of using weapons-derived plutonium in the fabrication of mixed-oxide (MOX) nuclear fuel for reactor-based plutonium disposition. The ultimate purpose of this work is to demonstrate adequate Thermally Induced Gallium Removal with a prototypic system. This Test Plan presents more than the FY98 R and D efforts in order to frame the Task in its entirety. To achieve the TIGRS Program objectives, R and D activities during the next two years will be focused on (1) process development leading to a prototypic TIGRS design, and (2) prototypic TIGRS design and testing leading to and including a prototypic demonstration of TIGRS operation. Both the process development and system testing efforts will consist of a series of surrogate-based cold tests and plutonium-based hot tests. Some of this testing has already occurred and will continue into FY99.

Buksa, J.J.; Butt, D.P.; Chidester, K.; DeMuth, S.F.; Havrilla, G.J.; James, C.A.; Kolman, D.G.

1997-12-24T23:59:59.000Z

314

Formation of copper-indium-selenide and/or copper-indium-gallium-selenide films from indium selenide and copper selenide precursors  

DOE Patents (OSTI)

Liquid-based indium selenide and copper selenide precursors, including copper-organoselenides, particulate copper selenide suspensions, copper selenide ethylene diamine in liquid solvent, nanoparticulate indium selenide suspensions, and indium selenide ethylene diamine coordination compounds in solvent, are used to form crystalline copper-indium-selenide, and/or copper indium gallium selenide films (66) on substrates (52).

Curtis, Calvin J. (Lakewood, CO); Miedaner, Alexander (Boulder, CO); Van Hest, Maikel (Lakewood, CO); Ginley, David S. (Evergreen, CO); Nekuda, Jennifer A. (Lakewood, CO)

2011-11-15T23:59:59.000Z

315

Method of fabricating an optoelectronic device having a bulk heterojunction  

DOE Patents (OSTI)

A method of fabricating an optoelectronic device comprises: depositing a first layer having protrusions over a first electrode, in which the first layer comprises a first organic small molecule material; depositing a second layer on the first layer such that the second layer is in physical contact with the first layer; in which the smallest lateral dimension of the protrusions are between 1 to 5 times the exciton diffusion length of the first organic small molecule material; and depositing a second electrode over the second layer to form the optoelectronic device. A method of fabricating an organic optoelectronic device having a bulk heterojunction is also provided and comprises: depositing a first layer with protrusions over an electrode by organic vapor phase deposition; depositing a second layer on the first layer where the interface of the first and second layers forms a bulk heterojunction; and depositing another electrode over the second layer.

Shtein, Max (Ann Arbor, MI); Yang, Fan (Princeton, NJ); Forrest, Stephen R. (Princeton, NJ)

2008-10-14T23:59:59.000Z

316

Bulk-Brane Interaction and Holographic Dark Energy  

E-Print Network (OSTI)

In this paper we consider the bulk-brane interaction to obtain the equation of state for the holographic energy density in non-flat universe enclosed by the event horizon measured from the sphere of horizon named $L$. We assumes that the cold dark matter energy density on the brane is conserved, but the holographic dark energy density on the brane is not conserved due to brane-bulk energy exchange. Our calculation show, taking $\\Omega_{\\Lambda}=0.73$ for the present time, the lower bound of $w_{\\rm \\Lambda}^{eff}$ is -0.9. This implies that one can not generate phantom-like equation of state from an interacting holographic dark energy model in non-flat universe.

M R Setare

2006-09-14T23:59:59.000Z

317

Evaluation of Potential Bulk System Reliability Impacts of Distributed Resources  

Science Conference Proceedings (OSTI)

In recent years, distributed energy resources (DER) penetration has increased, but projections for penetration over the next 10 years show dramatic increases. Much of this is made up of distributed solar photovoltaic (PV) power, which is estimated to expand significantly in the United States in coming years. This project describes how methods to assess bulk system reliability might need to be altered to account for increasing levels of DER, particularly PV. It also aims to produce mitigating strategies t...

2011-12-21T23:59:59.000Z

318

High Performance Bulk Data Brian Tierney and Joe Metzger, ESnet  

E-Print Network (OSTI)

High Performance Bulk Data Transfer Brian Tierney and Joe Metzger, ESnet Joint Techs, Columbus OH://mitas.csail.mit.edu/papers/ Bauer_Clark_Lehr_Broadband_Spee d_Measurements.pdf 7/12/10 ESnet Template Examples 17 Figure 11: Scatter memory in power of two sizes, so you may even need 16/1.5 = 11 times more buffer space! 7/12/10 ESnet

319

Superstructure of self-aligned hexagonal GaN nanorods formed on nitrided Si(111) surface  

SciTech Connect

We present here the spontaneous formation of catalyst-free, self-aligned crystalline (wurtzite) nanorods on Si(111) surfaces modified by surface nitridation. Nanorods grown by molecular beam epitaxy on bare Si(111) and non-stoichiometric silicon nitride interface are found to be single crystalline but disoriented. Those grown on single crystalline Si{sub 3}N{sub 4} intermediate layer are highly dense c-oriented hexagonal shaped nanorods. The morphology and the self-assembly of the nanorods shows an ordered epitaxial hexagonal superstructure, suggesting that they are nucleated at screw dislocations at the interface and grow spirally in the c-direction. The aligned nanorod assembly shows high-quality structural and optical emission properties.

Kumar, Praveen; Tuteja, Mohit; Kesaria, Manoj; Waghmare, U. V.; Shivaprasad, S. M. [Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064 (India)

2012-09-24T23:59:59.000Z

320

Understanding the Potential and Limitations of Dilute Nitride Alloys for Solar Cells  

DOE Green Energy (OSTI)

Dilute nitride alloys provide a powerful tool for engineering the band gap and lattice constant of III-V alloys. However, nitrogen degrades the performance of GaAs solar cells. This project seeks to understand and demonstrate the limits of performance of GaInNAs alloys by (a) correlating deep-level transient spectroscopy (DLTS) data with device performance and (b) using molecular beam epitaxy (MBE) to reduce background impurity concentrations.

Kurtz, S.; Ptak, A.; Johnston, S.; Kramer, C.; Young, M.; Friedman, D.; Geisz, J.; McMahon, W.; Kibbler, A.; Olson, J.; Crandall, R.; Branz, H.

2005-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

NIST Manuscript Publication Search  

Science Conference Proceedings (OSTI)

... Abstract: Although the efficiency of the Gallium Nitride (GaN) Light Emitting-Diode (LED) has improved in the past decade, a great opportunity ...

2013-12-19T23:59:59.000Z

322

at-meeting technical program in .pdf format  

Science Conference Proceedings (OSTI)

Jun 24, 1998 ... trical Engr., Walter Scott Engr. Center, Lincoln, NE 68588-0511 USA; ...... Radiative Efficiency of High Quality Gallium Nitride Thin Films: Peter.

323

NETL: NEPA Categorical Exclusions - January 2010 to March 2010  

NLE Websites -- All DOE Office Websites (Extended Search)

EEProject Management Center Y 352010 Advanced Epi Tools for Gallium Nitride Light Emitting Diode Devices Applied Materials, Inc. Santa Clara, CA EEBETD Y 352010 Red Birch...

324

Solid-State Lighting: 2012 Solid-State Lighting Manufacturing...  

NLE Websites -- All DOE Office Websites (Extended Search)

Frank Cerio, Veeco Instruments Advanced Epi Tools for Gallium Nitride Light Emitting Diode Devices Vivek Agrawal, Applied Materials Driving Down HB-LED Costs:...

325

Solid-State Lighting Issue 28: Scientific Literature (Mid May...  

NLE Websites -- All DOE Office Websites (Extended Search)

National University of Kaohsiung (Taiwan): "Wavelength shift of gallium nitride light emitting diode with p-down structure." W.H. Lan, IEEE Transactions on Electron Devices,...

326

Visit the National Academies Press online, the authoritative ...  

Science Conference Proceedings (OSTI)

... of the US electricity generation, and oil prices should not ... swings and a poor heating, ventilating, and air ... to gallium nitride growth is “home-built,” and ...

2012-09-27T23:59:59.000Z

327

Categorical Exclusion Determinations: American Recovery and Reinvestme...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination Transphorm, Inc. -High Performance Gallium Nitride High Electron Mobility Transistor Modules for Agile Power Electronics CX(s) Applied: B3.6 Date:...

328

Page not found | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Exclusion Determination Transphorm, Inc. -High Performance Gallium Nitride High Electron Mobility Transistor Modules for Agile Power Electronics CX(s) Applied: B3.6 Date:...

329

CX-009000: Categorical Exclusion Determination | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

0: Categorical Exclusion Determination 0: Categorical Exclusion Determination CX-009000: Categorical Exclusion Determination "High Quality, Low Cost Bulk Gallium Nitride (GaN) Substrates Grown by the Electrochemical Solution Growth Method CX(s) Applied: A9, B3.6 Date: 08/20/2012 Location(s): Missouri Offices(s): Golden Field Office The U.S. Department of Energy (DOE) is proposing to provide federal funding to MEMC Electronic Materials, Inc. MEMC would conduct research and development activities for a two phase project to develop a new process method for growing large bulk gallium nitrate (GaN) crystals at low cost with improved functional properties." CX-009000.pdf More Documents & Publications CX-000845: Categorical Exclusion Determination Energy Storage Systems 2010 Update Conference Presentations - Day 3,

330

Behavior of molybdenum nitrides as materials for electrochemical capacitors: Comparison with ruthenium oxide  

Science Conference Proceedings (OSTI)

Ruthenium oxide (RuO{sub 2}), formed as a thin film on a Ru or Ti metal substrate, exhibits a large specific (cm{sup {minus}2}) and almost constant, electrochemical capacitance over a 1.35 V range in aqueous H{sub 2}SO{sub 4}. This behavior has led to its investigation and use as a material for fabrication of supercapacitor devices. However, its cost has encouraged search for other materials exhibiting similar behavior. Work reported in the present paper evaluates two nitrides of Mo, Mo{sub 2}N and MoN, as substitutes for RuO{sub 2}. It is shown that very similar capacitance behavior to that of RuO{sub 2} films arises, e.g., in cyclic voltammetry and dc charging curves; in the former, almost mirror-image anodic and cathodic current-response profiles, characteristic of a capacitor, arise. However, the nitride materials have a substantially smaller voltage operating range of only some 0.7 V due to electrochemical decomposition above ca. 0.7 V vs. RHE. This limits their usefulness as a substitute for RuO{sub 2}. Of interest is that the nitride films exhibit potential-decay and potential-recovery on open circuit after respective charge and forced discharge. The decay and recovery processes are logarithmic in time, indicating the role of internal faradaic charge redistribution processes.

Liu, T.C.; Pell, W.G.; Conway, B.E. [Univ. of Ottawa, Ontario (Canada). Dept. of Chemistry; Roberson, S.L. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering

1998-06-01T23:59:59.000Z

331

Analytical and experimental evaluation of joining silicon carbide to silicon carbide and silicon nitride to silicon nitride for advanced heat engine applications Phase 2. Final report  

DOE Green Energy (OSTI)

The purpose of joining, Phase 2 was to develop joining technologies for HIP`ed Si{sub 3}N{sub 4} with 4wt% Y{sub 2}O{sub 3} (NCX-5101) and for a siliconized SiC (NT230) for various geometries including: butt joins, curved joins and shaft to disk joins. In addition, more extensive mechanical characterization of silicon nitride joins to enhance the predictive capabilities of the analytical/numerical models for structural components in advanced heat engines was provided. Mechanical evaluation were performed by: flexure strength at 22 C and 1,370 C, stress rupture at 1,370 C, high temperature creep, 22 C tensile testing and spin tests. While the silicon nitride joins were produced with sufficient integrity for many applications, the lower join strength would limit its use in the more severe structural applications. Thus, the silicon carbide join quality was deemed unsatisfactory to advance to more complex, curved geometries. The silicon carbide joining methods covered within this contract, although not entirely successful, have emphasized the need to focus future efforts upon ways to obtain a homogeneous, well sintered parent/join interface prior to siliconization. In conclusion, the improved definition of the silicon carbide joining problem obtained by efforts during this contract have provided avenues for future work that could successfully obtain heat engine quality joins.

Sundberg, G.J.; Vartabedian, A.M.; Wade, J.A.; White, C.S. [Norton Co., Northboro, MA (United States). Advanced Ceramics Div.

1994-10-01T23:59:59.000Z

332

PION CONDENSATION IN A RELATIVISTIC FIELD THEORY CONSISTENT WITH BULK PROPERTIES OF NUCLEAR MATTER  

E-Print Network (OSTI)

calculate nuclear binding energies in theories based on thetheory that accounts for the known bulk properties of nuclear matter, its saturation energytheory is constrained to reproduce the known bulk properties of nuclear matter, namely, its $aturation energy,

Banerjee, B.

2010-01-01T23:59:59.000Z

333

PION CONDENSATION IN A FIELD THEORY CONSISTENT WITH BULK PROPERTIES OF NUCLEAR MATTER  

E-Print Network (OSTI)

calculate nuclear binding energies in theories based on thetheory that accounts for the known bulk properties of nuclear matter, its saturation energytheory is constrained to reproduce the known bulk properties of nuclear matter, namely, its satruation energy,

Banerjee, B.

2010-01-01T23:59:59.000Z

334

Residential Bulk-Fed Wood-Pellet Central Boilers and Furnace...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Bulk-Fed Wood-Pellet Central Boilers and Furnace Rebate Program Residential Bulk-Fed Wood-Pellet Central Boilers and Furnace Rebate Program Eligibility Multi-Family Residential...

335

Fatigue Behavior of Tough Fe-Based Bulk-Metallic Glasses  

Science Conference Proceedings (OSTI)

A Fracture Mechanics Model of Fatigue Crack Propagation in Bulk-Metallic ... Air- Oxidation of a (Zr55Cu30Al10Ni5)98Er2 Bulk Metallic Glass at 350-500oc.

336

Analysis and forecast of the capesize bulk carriers shipping market using Artificial Neural Networks  

E-Print Network (OSTI)

Investing in the bulk carrier market constitutes a rather risky investment due to the volatility of the bulk carrier freight rates. In this study it is attempted to uncover the benefits of using Artificial Neural Networks ...

Voudris, Athanasios V

2006-01-01T23:59:59.000Z

337

Chemical thermodynamics of nuclear materials. IX. High temperature heat capacity of plutonium-3. 2 at. % gallium alloy  

Science Conference Proceedings (OSTI)

The heat capacity of delta-stabilized plutonium (Pu - 3.2 at. % Ga) has been determined from 330 to 700/sup 0/K by an adiabatic calorimeter. The heat capacity for this alloy may be expressed by: Cp (Pu-3.2 at. % Ga)/(J K/sup -1/ mol/sup -1/) = 39.249 - 0.0264 (T/K) + 3.595 x 10/sup 5/ (T/K)/sup 2/ - 2.506 x 10/sup 5/ (K/T)/sup 2/. It was found that a large contribution to the heat capacity is due to the electronic heat capacity. The thermal functions for this plutonium-gallium alloy are calculated to 700/sup 0/K.

Adams, R.O.; Oetting, F.L.

1982-01-01T23:59:59.000Z

338

An experiment to test the viability of a gallium-arsenide cathode in a SRF electron gun  

SciTech Connect

Strained gallium arsenide cathodes are used in electron guns for the production of polarized electrons. In order to have a sufficient quantum efficiency lifetime of the cathode the vacuum in the gun must be 10{sup -11} Torr or better, so that the cathode is not destroyed by ion back bombardment or through contamination with residual gases. All successful polarized guns are DC guns, because such vacuum levels can not be obtained in normal conducting RF guns. A superconductive RF gun may provide a sufficient vacuum level due to cryo-pumping of the cavity walls. We report on the progress of our experiment to test such a gun with normal GaAs-Cs crystals.

Kewisch,J.; Ben-Zvi, I.; Rao, T.; Burrill, A.; Pate, D.; Wu, Q.; Todd, R.; Wang, E.; Bluem, H.; Holmes, D.; Schultheiss, T.

2009-05-04T23:59:59.000Z

339

GaN-Ready Aluminum Nitride Substrates for Cost-Effective, Very Low Dislocation Density III-Nitride LED's  

SciTech Connect

The objective of this project was to develop and then demonstrate the efficacy of a costeffective approach for a low defect density substrate on which AlInGaN LEDs can be fabricated. The efficacy of this “GaN-ready” substrate would then be tested by growing high efficiency, long lifetime InxGa1-xN blue LEDs. The approach used to meet the project objectives was to start with low dislocation density AlN single-crystal substrates and grow graded AlxGa1-xN layers on top. Pseudomorphic AlxGa1-xN epitaxial layers grown on bulk AlN substrates were used to fabricate light emitting diodes and demonstrate better device performance as a result of the low defect density in these layers when benched marked against state-of-the-art LEDs fabricated on sapphire substrates. The pseudomorphic LEDs showed excellent output powers compared to similar wavelength devices grown on sapphire substrates, with lifetimes exceeding 10,000 hours (which was the longest time that could reliably be estimated). In addition, high internal quantum efficiencies were demonstrated at high driving current densities even though the external quantum efficiencies were low due to poor photon extraction. Unfortunately, these pseudomorphic LEDs require high Al content so they emit in the ultraviolet. Sapphire based LEDs typically have threading dislocation densities (TDD) > 108 cm-2 while the pseudomorphic LEDs have TDD ? 105 cm-2. The resulting TDD, when grading the AlxGa1-xN layer all the way to pure GaN to produce a “GaN-ready” substrate, has varied between the mid 108 down to the 106 cm-2. These inconsistencies are not well understood. Finally, an approach to improve the LED structures on AlN substrates for light extraction efficiency was developed by thinning and roughening the substrate.

Sandra Schujman; Leo Schowalter

2010-10-15T23:59:59.000Z

340

Effectiveness of three bulking agents for food waste composting  

Science Conference Proceedings (OSTI)

Rather than landfilling, composting the organic fraction of municipal solid wastes recycles the waste as a safe and nutrient enriched soil amendment, reduces emissions of greenhouse gases and generates less leachate. The objective of this project was to investigate the composting effectiveness of three bulking agents, namely chopped wheat (Triticum) straw, chopped mature hay consisting of 80% timothy (milium) and 20% clover (triphullum) and pine (pinus) wood shavings. These bulking agents were each mixed in duplicates at three different ratios with food waste (FW) and composted for 10 days using prototype in-vessel composters to observe their temperature and pH trends. Then, each mixture was matured in vertical barrels for 56 days to measure their mass loss and final nutrient content and to visually evaluate their level of decomposition. Chopped wheat straw (CWS) and chopped hay (CH) were the only two formulas that reached thermophilic temperatures during the 10 days of active composting when mixed with FW at a wet mass ratio of 8.9 and 8.6:1 (FW:CWS and FW:CH), respectively. After 56 days of maturation, these two formulas were well decomposed with no or very few recognizable substrate particles, and offered a final TN exceeding the original. Wood shavings (WS) produced the least decomposed compost at maturation, with wood particles still visible in the final product, and with a TN lower than the initial. Nevertheless, all bulking agents produced compost with an organic matter, TN, TP and TK content suitable for use as soil amendment.

Adhikari, Bijaya K. [Department of Bioresource Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore, Ste Anne de Bellevue (Quebec), H9X 3V9 (Canada); Barrington, Suzelle [Department of Bioresource Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore, Ste Anne de Bellevue (Quebec), H9X 3V9 (Canada)], E-mail: suzelle.barrington@mcgill.ca; Martinez, Jose [Cemagref, Rennes Regional Centre, 7 avenue du Cucille, CS 64427, F-35044 Rennes (France); King, Susan [Department of Bioresource Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore, Ste Anne de Bellevue (Quebec), H9X 3V9 (Canada)

2009-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Fabrication of Bulk-Si FinFET using CMOS compatible process  

Science Conference Proceedings (OSTI)

A new CMOS (Complementary Metal Oxide Semiconductor) compatible Bulk-Si FinFETs fabrication process has been proposed. Compared with conventional fabrication processes of SOI (Silicon On Insulator) and Bulk-Si FinFETs, this new approach is of low cost ... Keywords: Bulk, FinFET, Multi-gate

Huajie Zhou; Yi Song; Qiuxia Xu; Yongliang Li; Huaxiang Yin

2012-06-01T23:59:59.000Z

342

Bulk Burning Rate in Passive Reactive Diffusion. Peter Constantin Alexander Kiselev Adam Oberman  

E-Print Network (OSTI)

Bulk Burning Rate in Passive ­ Reactive Diffusion. Peter Constantin Alexander Kiselev Adam Oberman, diffuses, and reacts according to a KPP­type nonlinear reaction. We introduce a quantity, the bulk burning­defined notion of front speed. We establish rigorous lower bounds for the bulk burning rate that are linear

Ryzhik, Lenya

343

Spin Splitting and Spin Current in Strained Bulk Semiconductors  

SciTech Connect

We present a theory for two recent experiments in bulk strained semiconductors and show that a new, previously overlooked, strain spin-orbit coupling term may play a fundamental role. We propose simple experiments that could clarify the origin of strain-induced spin-orbit coupling terms in inversion asymmetric semiconductors. We predict that a uniform magnetization parallel to the electric field will be induced in the samples studied in for specific directions of the applied electric field. We also propose special geometries to detect spin currents in strained semiconductors.

Bernevig, B.Andrei; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-01-15T23:59:59.000Z

344

Efficient Bulk Data Replication for the Earth System Grid  

SciTech Connect

The Earth System Grid (ESG) community faces the difficult challenge of managing the distribution of massive data sets to thousands of scientists around the world. To move data replicas efficiently, the ESG has developed a data transfer management tool called the Bulk Data Mover (BDM). We describe the performance results of the current system and plans towards extending the techniques developed so far for the up- coming project, in which the ESG will employ advanced networks to move multi-TB datasets with the ulti- mate goal of helping researchers understand climate change and its potential impacts on world ecology and society.

Sim, Alex; Gunter, Dan; Natarajan, Vijaya; Shoshani, Arie; Williams, Dean; Long, Jeff; Hick, Jason; Lee, Jason; Dart, Eli

2010-03-10T23:59:59.000Z

345

Effects of Bulk Viscosity in Non-linear Bubble Dynamics  

E-Print Network (OSTI)

The non-linear bubble dynamics equations in a compressible liquid have been modified considering the effects of compressibility of both the liquid and the gas at the bubble interface. A new bubble boundary equation has been derived, which includes a new term resulted from the liquid bulk viscosity effects. The influence of this term has been numerically investigated considering the effects of water vapor and chemical reactions on the bubble evolution. The results clearly indicate that the new term has an important damping role at the collapse, so that its consideration decreases the amplitude of the bubble rebounds after the collapse. This damping feature is more remarkable for higher deriving pressures.

Moshaii, A; Taeibi-Rahni, M; Moshaii, Ahmad; Sadighi-Bonabi, Rasool; Taeibi-Rahni, Mohammad

2003-01-01T23:59:59.000Z

346

Non-Brownian molecular self-diffusion in bulk water  

E-Print Network (OSTI)

The paper presents the velocity autocorrelation spectrum of bulk water measured by a new technique of NMR modulated gradient spin echo method. This technique is unprecedented for the spectrum measurement in the frequency interval between a few Hz to about 100 kHz with respect to directness and clarity of results and shows that a simple model of Brownian self-diffusion is not applicable to describe the diffusion dynamics of water molecules. The observed temperature dependant spectra of water show the existence of a slow chain-like dynamics in water, which we explain by coupling of diffusing molecule to broken bonds in the hydrogen bond network.

Janez Stepišnik; Aleš Mohori?; Igor Serša

2010-10-06T23:59:59.000Z

347

Bulk separation of carbon dioxide from natural gas  

SciTech Connect

In the bulk separation of carbon dioxide from feedstocks containing same in admixture with relatively nonsorbable gases using a zeolitic molecular sieve to adsorb selectively the carbon dioxide, higher product purity is attained by terminating the adsorption stroke using the feedstock while the bed still has capacity to adsorb more carbon dioxide at the same conditions, then purging the void space hydrocarbons from the bed using product carbon dioxide at a high partial pressure, and finally desorbing the bed by pressure reduction. (3 claims)

Collins, J.J.

1973-08-14T23:59:59.000Z

348

Below-bandgap excitation of bulk semiconductors by twisted light  

E-Print Network (OSTI)

I theoretically investigate the response of bulk semiconductors to excitation by twisted light below the energy bandgap. To this end, I modify a well-known model of light-semiconductor interaction to account for the conservation of the light's momentum. I show that the excited states can be thought of as a superposition of slightly perturbed exciton states undergoing a complex center-of-mass motion. In addition, the absorption would occur at a slightly shifted energy (compared to plane waves) and would exhibit complex spatial patterns in the polarization and current.

Quinteiro, G F

2013-01-01T23:59:59.000Z

349

Radiation detector using a bulk high {Tc} superconductor  

DOE Patents (OSTI)

A radiation detector is provided, wherein a bulk high T superconducting sample is placed in a magnetic field and maintained at a superconducting temperature. Photons of incident radiation will cause localized heating in superconducting loops of the sample destroying trapped flux and redistributing the fluxons, and reducing the critical current of the loops. Subsequent cooling of the sample in the magnetic field will cause trapped flux redistributed Abrikosov fluxons and trapped Josephson fluxons. The destruction and trapping of the fluxons causes changes in the magnetization of the sample inducing currents in opposite directions in a pickup coil which is coupled by an input coil to an rf SQUID).

Artusom, J.F.; Franks, L.A.; Hull, K.L.; Symko, O.G.

1992-12-31T23:59:59.000Z

350

Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength  

DOE Patents (OSTI)

A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength are disclosed. The powder mixture includes (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12m[sup 2]g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder. No Drawings

Huckabee, M.L.; Buljan, S.T.; Neil, J.T.

1991-09-17T23:59:59.000Z

351

Optical and electrical properties of III-V nitride wide bandgap semiconductors. Annual report, April 1, 1997--May 31, 1998  

SciTech Connect

The objectives of this project were to investigate the optical and electrical properties of III-nitride wide bandgap semiconductors (GaN, InGaN, AlGaN) and quantum wells, to understand the fundamental optical transitions and impurity properties of these materials, to study the physics components of GaN-based devices, and to provide input for new approaches toward the improvement of materials quality and the optimization of device design. We were the first group to employ transport measurement techniques on the persistent photoconductivity (PPC) state to study the impurity properties of III-nitrides. We were also one of the few research groups m in the world to employ picosecond time-resolved photoluminescence (PL) measurement technique to study mechanisms of optical transitions, LED emission, and lasing m in GaN materials. During this funding period, we have investigated a variety of GaN samples and structures grown by MBE as well as by MOCVD. We have also made a significant progress in MOCVD GaN materials growth. This report briefly discusses the following accomplishments: effects of deep level impurities in the AlGaN/GaN heterostructures; materials characterization of III-nitrides alloys; optical studies of III-nitride epilayers and quantum wells; fabrication and optical studies of III-nitride microdisk arrays; and materials growth by MOCVD.

1998-06-01T23:59:59.000Z

352

Bulk heating cleans paraffinic bottoms from crude tanks  

SciTech Connect

It is often challenging to remove from service crude oil tanks that have been in use for many years. Bulk heating, as opposed to localized heating, has been used to successfully liquefy heavy paraffinic or asphaltic bases in crude oil tanks. The process provides economical product recovery, while minimizing waste production and reducing human exposure to hazardous working conditions. Statia Terminals Point Tupper Inc., Point Tupper, N.S., used bulk heating to remove 2 ft of weathered, paraffinic tank bottoms from six 450,000 bbl tanks that held Cabinda crude from West Africa. Immersion tube heaters were installed through the tank manholes and a diluent was added. Two 10-million BTU/hr propane burners supplied heat, and tank mixers operated continuously to aid in heat transfer. The tank contents were heated to 135 F and the temperature was held constant for 3 days. The resulting hot liquid was a pumpable and recoverable product. About 10 days were required to clean each tank. The paper describes the heating and cleaning operation as well as the economics of the Statia project.

Badrock, J. (Cooperheat Inc., Houston, TX (United States)); Coutu, R. (Cooperheat Inc., Mississauga, Ontario (Canada)); Johnson, N. (Statia Terminals N.V. St. Eustatius (Netherlands)); Martin, A. (Chicago Bridge and Iron Co., Oak Brook, IL (United States))

1995-02-20T23:59:59.000Z

353

Organization of bulk power markets: A concept paper  

SciTech Connect

The electricity industry in the US today is at a crossroads. The restructuring debate going on in most regions has made it clear that the traditional model of vertically integrated firms serving defined franchise areas and regulated by state commissions may not be the pattern for the future. The demands of large customers seeking direct access to power markets, the entry of new participants, and proposed reforms of the regulatory process all signify a momentum for fundamental change in the organization of the industry. This paper addresses electricity restructuring from the perspective of bulk power markets. The authors focus attention on the organization of electricity trade and the various ways it has been and might be conducted. Their approach concentrates on conceptual models and empirical case studies, not on specific proposals made by particular utilities or commissions. They review literature in economics and power system engineering that is relevant to the major questions. The objective is to provide conceptual background to industry participants, e.g. utility staff, regulatory staff, new entrants, who are working on specific proposals. While they formulate many questions, they do not provide definitive answers on most issues. They attempt to put the industry restructuring dialogue in a neutral setting, translating the language of economists for engineers and vice versa. Towards this end they begin with a review of the basic economic institutions in the US bulk power markets and a summary of the engineering practices that dominate trade today.

Kahn, E.; Stoft, S. [Lawrence Berkeley Lab., CA (United States). Energy and Environment Div.

1995-12-01T23:59:59.000Z

354

Method of fabricating an optoelectronic device having a bulk heterojunction  

DOE Patents (OSTI)

A method of fabricating an organic optoelectronic device having a bulk heterojunction comprises the steps of: depositing a first layer over a first electrode by organic vapor phase deposition, wherein the first layer comprises a first organic small molecule material; depositing a second layer on the first layer such that the second layer is in physical contact with the first layer, wherein the interface of the second layer on the first layer forms a bulk heterojunction; and depositing a second electrode over the second layer to form the optoelectronic device. In another embodiment, a first layer having protrusions is deposited over the first electrode, wherein the first layer comprises a first organic small molecule material. For example, when the first layer is an electron donor layer, the first electrode is an anode, the second layer is an electron acceptor layer, and the second electrode is a cathode. As a further example, when the first layer is an electron acceptor layer, the first electrode is a cathode, the second layer is an electron donor layer, and the second electrode is an anode.

Shtein, Max (Princeton, NJ); Yang, Fan (Princeton, NJ); Forrest, Stephen R. (Princeton, NJ)

2008-09-02T23:59:59.000Z

355

The effect of low levels of dopants upon the formation and properties of beta-phase molybdenum nitride  

Science Conference Proceedings (OSTI)

The addition of 1 wt% Pd, Au, Ni and Cu dopants has been demonstrated to strongly alter the morphology of beta-phase molybdenum nitride prepared by treatment of MoO{sub 3} with a 3/1 H{sub 2}/N{sub 2} mixture at 750 deg. C. Furthermore, the addition of Pd significantly enhances the surface area and the formation of the nitride phase. It is proposed that the facile formation of molybdenum bronzes in this system is important in this respect. The dopants have also been observed to modify the denitridation characteristics of the beta-phase, with an overall reduction of the proportion of NH{sub 3} formed upon using a 3/1 H{sub 2}/Ar mixture with respect to the undoped sample. - Graphical abstract: Low levels of Pd, Au, Ni and Cu dopant have significant effects upon the morphology, formation and dentitridation characteristics of beta-phase molybdenum nitride.

Cairns, A.G.; Gallagher, J.G. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Hargreaves, J.S.J., E-mail: justinh@chem.gla.ac.u [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Mckay, D. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Rico, J.L., E-mail: jlrico@umich.m [Laboratorio de Catalisis, Facultad de Ingenieria Quimica, Universidad Michoacana, Edificio E, CU, Morelia Mich, C.P. 58060 (Mexico); Wilson, K. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2010-03-15T23:59:59.000Z

356

Corrosion of Metal Inclusions In Bulk Vitrification Waste Packages  

SciTech Connect

The primary purpose of the work reported here is to analyze the potential effect of the release of technetium (Tc) from metal inclusions in bulk vitrification waste packages once they are placed in the Integrated Disposal Facility (IDF). As part of the strategy for immobilizing waste from the underground tanks at Hanford, selected wastes will be immobilized using bulk vitrification. During analyses of the glass produced in engineering-scale tests, metal inclusions were found in the glass product. This report contains the results from experiments designed to quantify the corrosion rates of metal inclusions found in the glass product from AMEC Test ES-32B and simulations designed to compare the rate of Tc release from the metal inclusions to the release of Tc from glass produced with the bulk vitrification process. In the simulations, the Tc in the metal inclusions was assumed to be released congruently during metal corrosion as soluble TcO4-. The experimental results and modeling calculations show that the metal corrosion rate will, under all conceivable conditions at the IDF, be dominated by the presence of the passivating layer and corrosion products on the metal particles. As a result, the release of Tc from the metal particles at the surfaces of fractures in the glass releases at a rate similar to the Tc present as a soluble salt. The release of the remaining Tc in the metal is controlled by the dissolution of the glass matrix. To summarize, the release of 99Tc from the BV glass within precipitated Fe is directly proportional to the diameter of the Fe particles and to the amount of precipitated Fe. However, the main contribution to the Tc release from the iron particles is over the same time period as the release of the soluble Tc salt. For the base case used in this study (0.48 mass% of 0.5 mm diameter metal particles homogeneously distributed in the BV glass), the release of 99Tc from the metal is approximately the same as the release from 0.3 mass% soluble Tc salt in the castable refractory block and it is released over the same time period as the salt. Therefore, to limit the impact of precipitated Fe on the release of 99Tc, both the amount of precipitated Fe in the BV glass and the diameter of these particles should be minimized.

Bacon, Diana H.; Pierce, Eric M.; Wellman, Dawn M.; Strachan, Denis M.; Josephson, Gary B.

2006-07-31T23:59:59.000Z

357

Influence of process parameters on properties of reactively sputtered tungsten nitride thin films  

SciTech Connect

Tungsten nitride (WN{sub x}) thin films were produced by reactive dc magnetron sputtering of tungsten in an Ar-N{sub 2} gas mixture. The influence of the deposition power on the properties of tungsten nitride has been analyzed and compared with that induced by nitrogen content variation in the sputtering gas. A combined analysis of structural, electrical and optical properties on thin WN{sub x} films obtained at different deposition conditions has been performed. It was found that at an N{sub 2} content of 14% a single phase structure of W{sub 2}N films was formed with the highest crystalline content. This sputtering gas composition was subsequently used for fabricating films at different deposition powers. Optical analysis showed that increasing the deposition power created tungsten nitride films with a more metallic character, which is confirmed with resistivity measurements. At low sputtering powers the resulting films were crystalline whereas, with an increase of power, an amorphous phase was also present. The incorporation of an excess of nitrogen atoms resulted in an expansion of the W{sub 2}N lattice and this effect was more pronounced at low deposition powers. Infrared analysis revealed that in WN{sub x} films deposited at low power, chemisorbed N{sub 2} molecules did not behave as ligands whereas at high deposition power they clearly appeared as ligands around metallic tungsten. In this study, the influence of the most meaningful deposition parameters on the phase transformation reaction path was established and deposition conditions suitable for producing thermally stable and highly crystalline W{sub 2}N films were found.

Addonizio, Maria L.; Castaldo, Anna; Antonaia, Alessandro; Gambale, Emilia; Iemmo, Laura [ENEA, Portici Research Centre, Piazzale E. Fermi 1, I-80055, Portici (Italy)

2012-05-15T23:59:59.000Z

358

III-antimonide/nitride based semiconductors for optoelectronic materials and device studies : LDRD 26518 final report.  

DOE Green Energy (OSTI)

The goal of this LDRD was to investigate III-antimonide/nitride based materials for unique semiconductor properties and applications. Previous to this study, lack of basic information concerning these alloys restricted their use in semiconductor devices. Long wavelength emission on GaAs substrates is of critical importance to telecommunication applications for cost reduction and integration into microsystems. Currently InGaAsN, on a GaAs substrate, is being commercially pursued for the important 1.3 micrometer dispersion minima of silica-glass optical fiber; due, in large part, to previous research at Sandia National Laboratories. However, InGaAsN has not shown great promise for 1.55 micrometer emission which is the low-loss window of single mode optical fiber used in transatlantic fiber. Other important applications for the antimonide/nitride based materials include the base junction of an HBT to reduce the operating voltage which is important for wireless communication links, and for improving the efficiency of a multijunction solar cell. We have undertaken the first comprehensive theoretical, experimental and device study of this material with promising results. Theoretical modeling has identified GaAsSbN to be a similar or potentially superior candidate to InGaAsN for long wavelength emission on GaAs. We have confirmed these predictions by producing emission out to 1.66 micrometers and have achieved edge emitting and VCSEL electroluminescence at 1.3 micrometers. We have also done the first study of the transport properties of this material including mobility, electron/hole mass, and exciton reduced mass. This study has increased the understanding of the III-antimonide/nitride materials enough to warrant consideration for all of the target device applications.

Kurtz, Steven Ross; Hargett, Terry W.; Serkland, Darwin Keith; Waldrip, Karen Elizabeth; Modine, Normand Arthur; Klem, John Frederick; Jones, Eric Daniel; Cich, Michael Joseph; Allerman, Andrew Alan; Peake, Gregory Merwin

2003-12-01T23:59:59.000Z

359

Annealing effects in hydrogenated silicon nitride films during high energy ion beam irradiation  

SciTech Connect

The annealing effects during energy recoil detection (ERD) analysis on the structure of hydrogenated silicon nitride film have been investigated by using fourier transform infrared (FTIR) spectroscopy. Hydrogenated silicon nitride films were prepared by plasma enhanced chemical vapor deposition with various substrate temperatures. A 2.5 MeV {sup 4}He{sup ++} ion beam was irradiated onto the film in a vacuum chamber at room temperature. The ERD signal was measured after various ion doses in order to determine the loss of hydrogen counts induced by the ion beam. The IR absorption spectrum was obtained in order to follow the film structural change which occurred due to the ion beam. The films deposited at 200 and 300 C show a significant decrease in the ERD count with increasing ion beam dose, while the film deposited at 400 C, shows no significant changes. The IR absorption peak position for Si-N stretching (830 cm{sup {minus}1}) shifted to smaller wave numbers after ion beam irradiation, while the Si-H stretching (2,160 cm{sup {minus}1}) shifted to the opposite direction. The peak position for N-H (3,360 cm{sup {minus}1}) shows no noticeable changes. Normalized peak area for the Si-N stretching increased after ion beam irradiation. The Si-H peak area decreased slightly. The N-H peak area decreased significantly. A recombination mechanism of the N and H radicals with excess Si radical coming from Si-Si bonds in Si-rich silicon nitride films has been suggested to explain the IR absorption spectral changes which have occurred due to ion beam irradiation.

Lee, J.W. [ETRI, Taejon (Korea, Republic of)]|[KAIST, Taejon (Korea, Republic of); Lee, S.H.; Yoo, H.J. [ETRI, Taejon (Korea, Republic of); Jhon, M.S.; Ryoo, R. [KAIST, Taejon (Korea, Republic of)

1995-09-01T23:59:59.000Z

360

The development of a porous silicon nitride crossflow filter; Final report, September 1988--September 1992  

Science Conference Proceedings (OSTI)

This report summarizes the work performed in developing a permeable form of silicon nitride for application to ceramic crossflow filters for use in advanced coal-fired electric power plants. The program was sponsored by the Department of Energy Morgantown Energy Technology Center and consisted of a design analysis and material development phase and a filter manufacture and demonstration phase. The crossflow filter design and operating requirements were defined. A filter design meeting the requirements was developed and thermal and stress analyses were performed. Material development efforts focused initially on reaction-bonded silicon nitride material. This approach was not successful, and the materials effort was refocused on the development of a permeable form of sintered silicon nitride (SSN). This effort was successful. The SSN material was used for the second phase of the program, filter manufacture and evaluation. Four half-scale SAN filter modules were fabricated. Three of the modules were qualified for filter performance tests. Tests were performed on two of the three qualified modules in the High-Temperature, High-Pressure facility at the Westinghouse Science and Technology Center. The first module failed on test when it expanded into the clamping device, causing dust leakage through the filter. The second module performed well for a cumulative 150-hr test. It displayed excellent filtration capability during the test. The blowback pulse cleaning was highly effective, and the module apparently withstood the stresses induced by the periodic pulse cleaning. Testing of the module resumed, and when the flow of combustion gas through the filter was doubled, cracks developed and the test was concluded.

NONE

1992-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Growth and morphology of 0.80 eV photoemitting indium nitride nanowires  

DOE Green Energy (OSTI)

InN nanowires with high efficiency photoluminescence emission at 0.80 eV are reported for the first time. InN nanowires were synthesized via a vapor solid growth mechanism from high purity indium metal and ammonia. The products consist of only hexagonal wurtzite phase InN. Scanning electron microscopy showed wires with diameters of 50-100nm and having fairly smooth morphologies. High-resolution transmission electron microscopy revealed high quality, single crystal InN nanowires which grew in the <0001> direction. The group-III nitrides have become an extremely important technological material over the past decade. They are commonly used in optoelectronic devices, such as high brightness light-emitting diodes (LEDs) and low wavelength laser diodes (LDs), as well as high power/high frequency electronic devices. Recently InN thin films grown by MOCVD and MBE were found to have a bandgap energy in the range of 0.7-0.9 eV, much lower than the value of {approx}1.9 eV found for InN films grown by sputtering. This large decrease in the direct bandgap transition energy and the ability to form ternary (InGaN) and quaternary (AlInGaN) alloys increases the versatility of group-III nitride optoelectronic devices, ranging from the near IR to the UV. Additionally, InN has some promising transport and electronic properties. It has the smallest effective electron mass of all the group-III nitrides which leads to high mobility and high saturation velocity10 and a large drift velocity at room temperature. As a result of these unique properties, there has been a large increase in interest in InN for potential use in optoelectronic devices, such as LDs and high efficiency solar cells, as well as high frequency/high power electronic devices.

Johnson, M.C.; Lee, C.J.; Bourret-Courchesne, E.D.; Konsek, S.L.; Aloni, S.; Han, W.Q.; Zettl, A.

2004-08-13T23:59:59.000Z

362

Very long single- and few-walled boron nitride nanotubes via the pressurized vapor/condenser method  

Science Conference Proceedings (OSTI)

Boron nitride nanotubes (BNNTs) are desired for their exceptional mechanical, electronic, thermal, structural, textural, optical, and quantum properties. A new method for producing long, small-diameter, single- and few-walled, boron nitride nanotubes (BNNTs) in macroscopic quantities is reported. The pressurized vapor/condenser (PVC) method produces, without catalysts, highly crystalline, very long, small-diameter, BNNTs. Palm-sized, cotton-like masses of BNNT raw material were grown by this technique and spun directly into centimeters-long yarn. Nanotube lengths were observed to be 100 times that of those grown by the most closely related method. Self-assembly and growth models for these long BNNTs are discussed.

Michael W. Smith, Kevin Jordan, Cheol Park, Jae-Woo Kim, Peter Lillehei, Roy Crooks, Joycelyn Harrison

2009-11-01T23:59:59.000Z

363

Irradiation Induced Dimensional Changes in Bulk Graphite; The theory  

E-Print Network (OSTI)

Basing on experimental data on irradiation-induced deformation of graphite we introduced a concept of diffuse domain structure developed in reactor graphite produced by extrusion. Such domains are considered as random continuous deviations of local graphite texture from the global one. We elucidate the origin of domain structure and estimate the size and the degree of orientational ordering of its domains. Using this concept we explain the well known radiation-induced size effect observed in reactor graphite. We also propose a method for converting the experimental data on shape-change of finite-size samples to bulk graphite. This method gives a more accurate evaluation of corresponding data used in estimations of reactor graphite components lifetime under irradiation.

Panyukov, S V; Arjakov, M V

2012-01-01T23:59:59.000Z

364

FINITE ELEMENT ANALYSIS OF BULK TRITIUM SHIPPING PACKAGE  

SciTech Connect

The Bulk Tritium Shipping Package was designed by Savannah River National Laboratory. This package will be used to transport tritium. As part of the requirements for certification, the package must be shown to meet the scenarios of the Hypothetical Accident Conditions (HAC) defined in Code of Federal Regulations Title 10 Part 71 (10CFR71). The conditions include a sequential 30-foot drop event, 30-foot dynamic crush event, and a 40-inch puncture event. Finite Element analyses were performed to support and expand upon prototype testing. Cases similar to the tests were evaluated. Additional temperatures and orientations were also examined to determine their impact on the results. The peak stress on the package was shown to be acceptable. In addition, the strain on the outer drum as well as the inner containment boundary was shown to be acceptable. In conjunction with the prototype tests, the package was shown to meet its confinement requirements.

Jordan, J.

2010-06-02T23:59:59.000Z

365

Methods of synthesizing hydroxyapatite powders and bulk materials  

SciTech Connect

Methods are provided for producing non-porous controlled morphology hydroxyapatite granules of less than 8 .mu.m by a spray-drying process. Solid or hollow spheres or doughnuts can be formed by controlling the volume fraction and viscosity of the slurry as well as the spray-drying conditions. Methods of providing for homogenous cellular structure hydroxyapatite granules are also provided. Pores or channels or varying size and number can be formed by varying the temperature at which a hydroxyapatite slurry formed in basic, saturated ammonium hydroxide is spray-dried. Methods of providing non-porous controlled morphology hydroxyapatite granules in ammonium hydroxide are also provided. The hydroxyapatite granules and bulk materials formed by these methods are also provided.

Luo, Ping (2843A Forest Ave., Berkeley, CA 94705)

1999-01-12T23:59:59.000Z

366

Methods of synthesizing hydroxyapatite powders and bulk materials  

DOE Patents (OSTI)

Methods are provided for producing non-porous controlled morphology hydroxyapatite granules of less than 8 {micro}m by a spray-drying process. Solid or hollow spheres or doughnuts can be formed by controlling the volume fraction and viscosity of the slurry as well as the spray-drying conditions. Methods of providing for homogeneous cellular structure hydroxyapatite granules are also provided. Pores or channels or varying size and number can be formed by varying the temperature at which a hydroxyapatite slurry formed in basic, saturated ammonium hydroxide is spray-dried. Methods of providing non-porous controlled morphology hydroxyapatite granules in ammonium hydroxide are also provided. The hydroxyapatite granules and bulk materials formed by these methods are also provided. 26 figs.

Luo, P.

1999-01-12T23:59:59.000Z

367

Bulk-edge correspondence in fractional Chern insulators  

E-Print Network (OSTI)

It has been recently realized that strong interactions in topological Bloch bands give rise to the appearance of novel states of matter. Here we study connections between these systems -- fractional Chern insulators and the fractional quantum Hall states -- via generalization of a gauge-fixed Wannier-Qi construction in the cylinder geometry. Our setup offers a number of important advantages compared to the earlier exact diagonalization studies on a torus. Most notably, it gives access to edge states and to a single-cut orbital entanglement spectrum, hence to the physics of bulk-edge correspondence. It is also readily implemented in the state-of-the-art density matrix renormalisation group method that allows for numerical simulations of significantly larger systems. We demonstrate our general approach on examples of flat-band models on ruby and kagome lattices at bosonic filling fractions $\

Zhao Liu; D. L. Kovrizhin; Emil J. Bergholtz

2013-04-04T23:59:59.000Z

368

Irradiation Induced Dimensional Changes in Bulk Graphite; The theory  

E-Print Network (OSTI)

Basing on experimental data on irradiation-induced deformation of graphite we introduced a concept of diffuse domain structure developed in reactor graphite produced by extrusion. Such domains are considered as random continuous deviations of local graphite texture from the global one. We elucidate the origin of domain structure and estimate the size and the degree of orientational ordering of its domains. Using this concept we explain the well known radiation-induced size effect observed in reactor graphite. We also propose a method for converting the experimental data on shape-change of finite-size samples to bulk graphite. This method gives a more accurate evaluation of corresponding data used in estimations of reactor graphite components lifetime under irradiation.

S. V. Panyukov; A. V. Subbotin; M. V. Arjakov

2012-10-14T23:59:59.000Z

369

Feed Variability and Bulk Vitrification Glass Performance Assessment  

Science Conference Proceedings (OSTI)

The supplemental treatment (ST) bulk vitrification process will obtain its feed, consisting of low-activity waste (LAW), from more than one source. One purpose of this letter report is to describe the compositional variability of the feed to ST. The other is to support the M-62-08 decision by providing a preliminary assessment of the effectiveness of bulk vitrification (BV), the process that has been selected to perform supplemental treatment, in handling the ST feed envelope. Roughly nine-tenths of the ST LAW feed will come from the Waste Treatment Plant (WTP) pretreatment. This processed waste is expected to combine (1) a portion of the same LAW feed sent to the WTP melters and (2) a dilute stream that is the product of the condensate from the submerged-bed scrubber (SBS) and the drainage from the electrostatic precipitator (WESP), both of which are part of the LAW off-gas system. The manner in which the off-gas-product stream is concentrated to reduce its volume, and the way in which the excess LAW and off-gas product streams are combined, are part of the interface between WTP and ST and have not been determined. This letter report considers only one possible arrangement, in which half of the total LAW is added to the off-gas product stream, giving an estimated ST feed stream from WTP. (Total LAW equals that portion of LAW sent to the WTP LAW vitrification plant (WTP LAW) plus the LAW not currently treatable in the LAW vitrification plant due to capacity limitations (excess)).

Mahoney, Lenna A.; Vienna, John D.

2005-01-10T23:59:59.000Z

370

Stresses resulting from compression of bulk cotton lint fibers  

E-Print Network (OSTI)

The modulus of elasticity, Poisson's ratio and shear modulus of bulk cotton lint fibers were determined. The cotton lint was compressed in an MTS machine to a predetermined density, and the resilient forces induced by the cotton lint after being compressed were measured. Finite element analysis was used to model force on cotton bale ties, and determine the magnitude of the resilient forces on the bale ties. The nodal forces on the bale tie material were evaluated for three different bale tie materials to determine if bale tie breakage would occur. Young's modulus of bulk lint cotton was found to be 9 MPa and the Poisson's ratio was 0. 1, while 12 MPa was recorded for the shear modulus. The FEA analysis showed that round steel ties, at six ties per bale were loaded at 5.9 % of their tensile yield strength, and at 5.4 % for eight ties per bale. Plastic ties were loaded at 11.9 % of their tensile yield strength at six ties per bale, and at 10.8 % at eight ties per bale. The flat steel ties were loaded at 10.7 % of their tensile yield strength at six ties per bale, and at 9.4 % at eight ties per bale. Depth adjustment on the basis of the sample depth to the actual depth resulted in plastic ties being loaded to 84 % of their tensile yield strength at six ties per bale. Round steel ties were loaded to 62% and the flat steel ties were loaded to 66% at six ties per bale.

Chimbombi, Ezekiel Maswe

1998-01-01T23:59:59.000Z

371

Strength and fatigue of NT551 silicon nitride and NT551 diesel exhaust valves  

DOE Green Energy (OSTI)

The content of this report is excerpted from Mark Andrew's Ph.D. Thesis (Andrews, 1999), which was funded by a DOE/OTT High Temperature Materials Laboratory Graduate Fellowship. It involves the characterization of NT551 and valves fabricated with it. The motivations behind using silicon nitride (Si{sub 3}N{sub 4}) as an exhaust valve for a diesel engine are presented in this section. There are several economic factors that have encouraged the design and implementation of ceramic components for internal combustion (IC) engines. The reasons for selecting the diesel engine valve for this are also presented.

Andrews, M.J.; Werezczak, A.A.; Kirkland, T.P.; Breder, K.

2000-02-01T23:59:59.000Z

372

Rf-plasma synthesis of nanosize silicon carbide and nitride. Final report  

DOE Green Energy (OSTI)

A pulsed rf plasma technique is capable of generating ceramic particles of 10 manometer dimension. Experiments using silane/ammonia and trimethylchlorosilane/hydrogen gas mixtures show that both silicon nitride and silicon carbide powders can be synthesized with control of the average particle diameter from 7 to 200 nm. Large size dispersion and much agglomeration appear characteristic of the method, in contrast to results reported by another research group. The as produced powders have a high hydrogen content and are air and moisture sensitive. Post-plasma treatment in a controlled atmosphere at elevated temperature (800{degrees}C) eliminates the hydrogen and stabilizes the powder with respect to oxidation or hydrolysis.

Buss, R.J.

1997-02-01T23:59:59.000Z

373

Synthesis and optical properties of CsC1-doped gallium-sodium-sulfide glasses  

SciTech Connect

Ga{sub 2}S{sub 3}-Na{sub 2}S (GNS) glasses doped with CsCl were synthesized in open crucibles under inert atmosphere. The evaporative loss of CsCl during glass melting was measured by energy dispersive X-ray spectroscopy and corrected for by biasing the CsCl concentration in the mixture of starting materials to obtain glasses with accurately controlled stoichiometry. Glass transition temperatures, refractive index dispersions, and band edge energies were measured for four GNS:CsCl glasses, and the respective values were found to significantly improve over earlier studies that did not mitigate CsCl evaporative losses. The refractive index dispersion measurements indicate that the Cs{sup +} and Cl{sup -} radii are 16% larger in GNS:CsCl glass than in bulk crystalline CsCl. The band edge energy increases from 2.97 eV in GNS glass to 3.32 eV in GNS glass doped with 20 mol% CsCl as a result of introducing Cl{sup -} ions having a large optical electronegativity. The large bandgap of 3.32 eV and the low (450 cm{sup -1}) phonon energy make GNS:20%CsCl an attractive host material for rare-earth ions with radiative transitions in the near ultra-violet, visible, and near-infrared spectral regions.

Hehlen, Markus P [Los Alamos National Laboratory; Bennett, Bryan L [Los Alamos National Laboratory; Williams, Darrick J [Los Alamos National Laboratory; Muenchausen, Ross E [Los Alamos National Laboratory; Castro, Alonso [Los Alamos National Laboratory; Tornga, Stephanie C [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

374

Reduction in interface state density of Al{sub 2}O{sub 3}/InGaAs metal-oxide-semiconductor interfaces by InGaAs surface nitridation  

Science Conference Proceedings (OSTI)

We report the decrease in interface trap density (D{sub it}) in Al{sub 2}O{sub 3}/InGaAs metal-oxide-semiconductor (MOS) capacitors by using electron cyclotron resonance plasma nitridation of the InGaAs surfaces. The impact of the nitridation process on the MOS interface properties is quantitatively examined. The plasma nitridation process is observed to form a nitrided layer at the InGaAs surface. The nitridation using microwave power (P{sub microwave}) of 250 W and nitridation time (t{sub nitridation}) of 420 s can form Al{sub 2}O{sub 3}/InGaAs MOS interfaces with a minimum D{sub it} value of 2.0 Multiplication-Sign 10{sup 11} cm{sup -2} eV{sup -1}. On the other hand, the nitridation process parameters such as P{sub microwave} and t{sub nitridation} are found to strongly alter D{sub it} (both decrease and increase are observed) and capacitance equivalent thickness (CET). It is found that the nitridation with higher P{sub microwave} and shorter t{sub nitridation} can reduce D{sub it} with less CET increase. Also, it is observed that as t{sub nitridation} increases, D{sub it} decreases first and increases later. It is revealed from XPS analyses that minimum D{sub it} can be determined by the balance between the saturation of nitridation and the progress of oxidation. As a result, it is found that the superior MOS interface formed by the nitridation is attributable to the existence of oxide-less InGaN/InGaAs interfaces.

Hoshii, Takuya; Lee, Sunghoon; Suzuki, Rena; Taoka, Noriyuki; Yokoyama, Masafumi; Takenaka, Mitsuru; Takagi, Shinichi [Department of Electrical Engineering and Information Systems, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Yamada, Hishashi; Hata, Masahiko [Sumitomo Chemical Co. Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294 (Japan); Yasuda, Tetsuji [National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

2012-10-01T23:59:59.000Z

375

“Structural Transformations in Ceramics: Perovskite-like Oxides and Group III, IV, and V Nitrides  

SciTech Connect

1 Overview of Results and their Significance Ceramic perovskite-like oxides with the general formula (A. A0. ...)(B. B0. ...)O3and titanium-based oxides are of great technological interest because of their large piezoelectric and dielectric response characteristics.[1] In doped and nanoengineered forms, titantium dioxide finds increasing application as an organic and hydrolytic photocatalyst. The binary main-group-metal nitride compounds have undergone recent advancements of in-situ heating technology in diamond anvil cells leading to a burst of experimental and theoretical interest. In our DOE proposal, we discussed our unique theoretical approach which applies ab initio electronic calculations in conjunction with systematic group-theoretical analysis of lattice distortions to study two representative phase transitions in ceramic materials: (1) displacive phase transitions in primarily titanium-based perovskite-like oxide ceramics, and (2) reconstructive phase transitions in main-group nitride ceramics. A sub area which we have explored in depth is doped titanium dioxide electrical/optical properties.

James P. Lewis (PI, former Co-PI), Dorian M. Hatch (Co-PI, former PI), and Harold T. Stokes (Co-PI)

2006-12-31T23:59:59.000Z

376

Ferromagnetism in Doped Thin-Film Oxide and Nitride Semiconductors and Dielectrics  

SciTech Connect

The principal goal in the field of high-Tc ferromagnetic semiconductors is the synthesis, characterization and utilization of semiconductors which exhibit substantial carrier spin polarization at and above room temperature. Such materials are of critical importance in the emerging field of semiconductor spintronics. The interaction leading to carrier spin polarization, exchange coupling between the dopant spins and the valence or conduction band, is known to be sufficiently weak in conventional semiconductors, such as GaAs and Si, that magnetic ordering above cryogenic temperatures is essentially impossible. Since the provocative theoretical predictions of Tc above ambient in p-Mn:ZnO and p-Mn:GaN (T. Dietl et al., Science 287 1019 (2000)), and the observation of room-temperature ferromagnetism in Co:TiO2 anatase (Y. Matsumoto et al., Science 291 854 (2001)), there has been a flurry of work in oxides and nitrides doped with transition metals with unpaired d electrons. It has even been claimed that room-temperature ferromagnetism can be obtained in certain d0 transition metals oxides without a dopant. In this Report, the field of transition metal doped oxides and nitrides is critically reviewed and assessed from a materials science perspective. Since much of the field centers around thin film growth, this Report focuses on films prepared not only by conventional vacuum deposition methods, but also by spin coating colloidal nanoparticles.

Chambers, Scott A.

2006-10-01T23:59:59.000Z

377

Diffusion Barrier Properties of Nitride-Based Coatings on Fuel Cladding  

SciTech Connect

In this work titanium nitride (TiN) and zirconium nitride (ZrN) coatings are proposed as diffusion barriers between stainless steel nuclear fuel cladding and lanthanide fission products. TiN and ZrN have been coated as barrier materials between pure Fe and Ce, i.e. diffusion couples of Fe/TiN/Ce and Fe/ZrN/Ce, annealed up to a temperature of 600 degrees C, and compared to the diffusion behavior of uncoated Fe/Ce. Backscattered electron images and electron dispersive X-ray spectroscopy measurements confirm that, with a 500 nm TiN or ZrN layer, no obvious diffusion is observed between Fe and Ce. Basic diffusion characteristics of the Fe/Ce couple have also been measured and compared with the TiN and ZrN coated ones. The results strongly advocate that TiN and ZrN coatings provide reliable diffusion barrier characteristics against Ce and possibly other lanthanide fission products.

Fauzia Khatkhatay; Jie Jian; Liang Jiao; Qing Su; Jian Gan; James I. Cole; Haiyan Wang

2013-12-01T23:59:59.000Z

378

“Work-Hardenable” Ductile Ti-based Bulk Metallic Glass Matrix ...  

Science Conference Proceedings (OSTI)

Highly processable bulk metallic glasses (BMGs) with unique supercooled liquid ... Application of Metallic Glass for High Performance Si Solar Cell: Oxidation ...

379

Oxidation Resistance of Zr- and Ti- Based Bulk Metallic Glasses in ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2012 TMS Annual Meeting & Exhibition. Symposium , Bulk Metallic Glasses IX. Presentation Title, Oxidation Resistance of Zr- and ...

380

Mechanical Properties of Al-Ni-Zr Bulk Metallic Glasses Interpreted ...  

Science Conference Proceedings (OSTI)

Symposium, M. Bulk Metallic Glasses, Nanocrystalline Materials, and ... Application of Metallic Glass for High Performance Si Solar Cell: Oxidation Behavior of ...

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Fabrication of Cu-Zr-based Bulk Metallic Glasses by Vertical Twin ...  

Science Conference Proceedings (OSTI)

Symposium, M. Bulk Metallic Glasses, Nanocrystalline Materials, and ... Application of Metallic Glass for High Performance Si Solar Cell: Oxidation Behavior of ...

382

Investigation of Torsion Fracture on Zr-based Bulk Metallic Glass  

Science Conference Proceedings (OSTI)

Symposium, M. Bulk Metallic Glasses, Nanocrystalline Materials, and ... Application of Metallic Glass for High Performance Si Solar Cell: Oxidation Behavior of ...

383

Crack-resistance Curve of a Zr-Ti-Cu-Al Bulk Metallic Glass with ...  

Science Conference Proceedings (OSTI)

Symposium, M. Bulk Metallic Glasses, Nanocrystalline Materials, and ... Application of Metallic Glass for High Performance Si Solar Cell: Oxidation Behavior of ...

384

Temperature and Frequency Dependent Conduction Mechanisms Within Bulk Carbon Nanotube Materials.  

E-Print Network (OSTI)

??The resistance of three types of bulk carbon nanotube (CNT) materials (floating catalyst CNT yarn, forest grown CNT yarn, and super acid spun CNT fiber)… (more)

Bulmer, John Simmons

2010-01-01T23:59:59.000Z

385

M1: Fabrication of Bulk Nanocrystalline Ni-W with Plastic ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, The 8th Pacific Rim International Congress on Advanced Materials and Processing. Symposium, M. Bulk Metallic Glasses, ...

386

Power mixture and green body for producing silicon nitride base & articles of high fracture toughness and strength  

DOE Patents (OSTI)

A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength. The powder mixture includes 9a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon mitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12m.sup.2 g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified articel an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder.

Huckabee, Marvin L. (Marlboro, MA); Buljan, Sergej-Tomislav (Acton, MA); Neil, Jeffrey T. (Acton, MA)

1991-01-01T23:59:59.000Z

387

Electrical Bias as an Alternate Method for Reproducible Measurement of Copper Indium Gallium Diselenide (CIGS) Photovoltaic Modules: Preprint  

DOE Green Energy (OSTI)

Light-to-dark metastable changes in thin-film photovoltaic (PV) modules can introduce uncertainty when measuring module performance on indoor flash testing equipment. This study describes a method to stabilize module performance through forward-bias current injection rather than light exposure. Measurements of five pairs of thin-film copper indium gallium diselenide (CIGS) PV modules indicate that forward-bias exposure maintained the PV modules at a stable condition (within 1%) while the unbiased modules degraded in performance by up to 12%. It was additionally found that modules exposed to forward bias exhibited stable performance within about 3% of their long-term outdoor exposed performance. This carrier-injection method provides a way to reduce uncertainty arising from fast transients in thin-film module performance between the time a module is removed from light exposure and when it is measured indoors, effectively simulating continuous light exposure by injecting minority carriers that behave much as photocarriers do. This investigation also provides insight into the initial light-induced transients of thin-film modules upon outdoor deployment.

Deline, C.; Stokes, A.; Silverman, T. J.; Rummel, S.; Jordan, D.; Kurtz, S.

2012-08-01T23:59:59.000Z

388

Derived reference doses for three compounds used in the photovoltaics industry: Copper indium diselenide, copper gallium diselenide, and cadmium telluride  

DOE Green Energy (OSTI)

Polycrystalline thin-film photovoltaic modules made from copper indium diselenide (CIS), copper gallium diselenide (CGS), and cadmium telluride (CdTe) arc nearing commercial development. A wide range of issues are being examined as these materials move from the laboratory to large-scale production facilities to ensure their commercial success. Issues of traditional interest include module efficiency, stability and cost. More recently, there is increased focus given to environmental, health and safety issues surrounding the commercialization of these same devices. An examination of the toxicological properties of these materials, and their chemical parents is fundamental to this discussion. Chemicals that can present large hazards to human health or the environment are regulated often more strictly than those that are less hazardous. Stricter control over how these materials are handled and disposed can increase the costs associated with the production and use of these modules dramatically. Similarly, public perception can be strongly influenced by the inherent biological hazard that these materials possess. Thus, this report: presents a brief background tutorial on how toxicological data are developed and used; overviews the toxicological data available for CIS, CGS and CdTe; develops ``reference doses`` for each of these compounds; compares the reference doses for these compounds with those of their parents; discusses the implications of these findings to photovoltaics industry.

Moskowitz, P.D.; Bernholc, N.; DePhillips, M.P.; Viren, J.

1995-07-06T23:59:59.000Z

389

Low energy solar neutrino experiments: The Soviet American Gallium Experiment (SAGE). Final report, August 12, 1988--October 31, 1994  

SciTech Connect

Two {sup 71}Ga experiments are currently in operation. The first is the 60 ton Soviet American Gallium Experiment (SAGE) at Baksan, which has recently reported a signal level of 73+18/{minus}16(stat)+5/{minus}7(syst) SNU; the second is the 30 ton GALLEX experiment at Gran Sasso, which sees 87{+-}14{+-}7 SNU. Both results are consistent, and both suggest a neutrino flux level low compared to the total expected from standard solar model calculations. It is not possible, however, to make a case for flux levels lower than the p-p prediction. Assuming the experiments are correct (Neutrino source calibrations are planned for both SAGE and GALLEX in the near future.), it is not at all clear yet whether the answer lies with the neutrino physics, solar physics, or a combination of both. Nevertheless, though solar model effects cannot be ruled out, if the Homestake and Kamiokande results are taken at face value, then these two experiments alone imply that neutrino oscillations or some similar particle physics result must be present to some degree. This report reviews the SAGE experiment and recent results. Non-radiochemical experiments are also discussed, with an emphasis on the Kamiokande water Cerenkov results.

NONE

1995-04-01T23:59:59.000Z

390

Quasiparticle energy studies of bulk semiconductors, surfaces and nanotubes  

DOE Green Energy (OSTI)

Effects of many-body effects on electronic excitation energies (quasiparticle band structure) of these materials are explored. GW approximation, including local field effects, for self-energy operator is used to calculate quasi-particle energies. The newly discovered carbon nanotubes are studied; structural stability and band structures are calculated. BN nanotubes are also studied, and their stability is predicted. Unexpected electronic features are predicted for both systems. Filling of carbon nanotubes with metal atoms and the doping of BN nanotubes by carbon and other impurites is also studied. The occupied surface states at H/Si(111)-(1{times}1) surface are studied; it is shown that the electronic structure requires a full quasiparticle calculation even for this simple chemisorption system. The core level shift of the Si 2p levels for atoms near the H/Si(111)-(1{times}1) surface is calculated; a simple first order perturbation theory using pseudopotential and the local density approximation gives good results for the photoemission spectra of the core electrons. The quasiparticle energies of bulk hexagonal BN and those of an isolated BN sheet are studied; this provides an understanding of the quasiparticle band structure of BN nanotubes. A nearly free electron state with a wavefunction in the interlayer or vacuum region composes the bottom of the conduction bands. A mixed-space formalism is presented for calculating the dynamical screening effects and electron self-energy operator in solids; this provides an efficient algorithm to calculate quasiparticle energies for large systems.

Blase, X.F.

1994-12-01T23:59:59.000Z

391

Short range chemical ordering in bulk metallic glasses  

DOE Green Energy (OSTI)

We provide direct experimental evidence for a non-random distribution of atomic constituents in Zr-based multi-component bulk metallic glasses using positron annihilation spectroscopy. The Ti content around the open-volume regions is significantly enhanced at the expense of Cu and Ni, indicating that Cu and Ni occupy most of the volume bounded by their neighboring atoms while Ti and Zr are less closely packed and more likely to be associated with open-volume regions. Temperature-dependent measurements indicate the presence of at least two different characteristic sizes for the open volume regions. Measurements on hydrogen-charged samples show that the larger open-volume regions can be filled by hydrogen up to a critical density. Beyond this critical density, local atomic-scale open-volume damage is created in the sample to accommodate additional hydrogen. The onset of this local damage in positron annihilation data coincides with the onset of volume expansion in X-ray diffraction data.

Sterne, P A; Asoka-Kumar, P; Hartley, J H; Howell, R H; Nieh, T G; Flores, K M; Suh, D; Dauskardt, R H

2001-01-03T23:59:59.000Z

392

Higgs mechanism near the 5d bulk phase transition  

E-Print Network (OSTI)

We present a non-perturbative model of Gauge-Higgs Unification. We consider a five-dimensional pure SU(2) gauge theory with orbifold boundary conditions along the fifth dimension, such that the symmetry is reduced to U(1) at the fixed points of the orbifold action. The spectrum on the four-dimensional boundary hyperplanes includes, apart from the U(1) gauge boson, also a complex scalar, interpreted as a simplified version of the Standard Model Higgs field. The gauge theory is defined on a Euclidean lattice which is anisotropic in the extra dimension. Using the boundary Wilson Loop and the observable that represents the scalar and in the context of an expansion in fluctuations around a Mean-Field background, we show that a) near the bulk phase transition the model tends to reduce dimensionally to a four-dimensional gauge-scalar theory, b) the boundary U(1) gauge symmetry breaks spontaneously due to the broken translational invariance along the fifth dimension, c) it is possible to construct renormalized trajectories on the phase diagram along which the Higgs mass is constant as the lattice spacing is varied, d) by taking a continuum limit in the regime where the anisotropy parameter is small, it is possible to predict the existence of a Z' state with a mass around 1 TeV.

Nikos Irges; Francesco Knechtli; Kyoko Yoneyama

2012-12-21T23:59:59.000Z

393

LATE NEWS: KK3, Non-Catalytic Synthesis of GaN Nanostructures ...  

Science Conference Proceedings (OSTI)

We have observed the synthesis of gallium nitride (GaN) nanopowders on boron ... as 400°C. The synthesis process is based on the reaction between gallium atoms from the decomposition of gallium acetylacetonate and ammonia gas molecules. ... the crystal structure and growth mechanism of the grown nanostructures.

394

Current industry practices in bulk transmission outage data collection and analysis  

SciTech Connect

This paper focuses on the state-of-the-art bulk transmission outage data collection and analysis. Included in this discussion is the motivation for interest, single/multiple outage event analysis, and identification of where to obtain data on weather conditions which impact the performance of bulk transmission.

Not Available

1992-02-01T23:59:59.000Z

395

Bulk superconductivity in Type II superconductors near the second critical field  

E-Print Network (OSTI)

We consider superconductors of Type II near the transition from the 'bulk superconducting' to the 'surface superconducting' state. We prove a new $L^{\\infty}$ estimate on the order parameter in the bulk, i.e. away from the boundary. This solves an open problem posed by Aftalion and Serfaty.

S. Fournais; B. Helffer

2008-02-14T23:59:59.000Z

396

Comparison of Bulk and Bin Warm-Rain Microphysics Models Using a Kinematic Framework  

Science Conference Proceedings (OSTI)

This paper discusses the development and testing of a bulk warm-rain microphysics model that is capable of addressing the impact of atmospheric aerosols on ice-free clouds. Similarly to previous two-moment bulk schemes, this model predicts the ...

Hugh Morrison; Wojciech W. Grabowski

2007-08-01T23:59:59.000Z

397

Bulk viscous fluid hypersurface - homogeneous cosmological models with time varying G and ?  

Science Conference Proceedings (OSTI)

Hypersurface - homogeneous cosmological models containing a bulk viscous fluid with time varying G and ? have been presented. We have shown that the field equations are solvable for any arbitrary cosmic scale function. The viscosity coefficient ... Keywords: bulk viscosity, hypersurface - homogeneous, variable G and ?. LATEX

Shri Ram; M. K. Verma

2010-02-01T23:59:59.000Z

398

Parameterization of Heterogeneous Droplet Chemistry for Use in Bulk Cloud Models  

Science Conference Proceedings (OSTI)

Comparison of in-cloud sulfate production by a bulk-parameterized cloud model, a modified bulk parameterized model, and an explicit microphysical model for a wide variety of scenarios has been used as the basis for deriving a parameterization of ...

Po-Fat Yuen; Dean A. Hegg; Timothy V. Larson; Mary C. Barth

1996-05-01T23:59:59.000Z

399

PIP: A multichannel, TDMA-based MAC for efficient and scalable bulk transfer in sensor networks  

Science Conference Proceedings (OSTI)

In this article, we consider the goal of achieving high throughput in a wireless sensor network. Our work is set in the context of those wireless sensor network applications which collect and transfer bulk data. We present PIP (Packets in Pipe), a MAC ... Keywords: Bulk data transfer, MAC, TDMA, pipelining, throughput optimization, wireless sensor network applications

Vijay Gabale; Kameswari Chebrolu; Bhaskaran Raman; Sagar Bijwe

2012-09-01T23:59:59.000Z

400

Gold Nanoparticles Supported on Carbon Nitride: Influence of Surface Hydroxyls on Low Temperature Carbon Monoxide Oxidation  

SciTech Connect

This paper reports the synthesis of 2.5 nm gold clusters on the oxygen free and chemically labile support carbon nitride (C3N4). Despite having small particle sizes and high enough water partial pressure these Au/C3N4 catalysts are inactive for the gas phase and liquid phase oxidation of carbon monoxide. The reason for the lack of activity is attributed to the lack of surface OH groups on the C3N4. These OH groups are argued to be responsible for the activation of CO in the oxidation of CO. The importance of basic OH groups explains the well document dependence of support isoelectric point versus catalytic activity.

Singh, Joseph A [ORNL; Dudney, Nancy J [ORNL; Li, Meijun [ORNL; Overbury, Steven {Steve} H [ORNL; Veith, Gabriel M [ORNL

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Vacancies in fully hydrogenated boron nitride layer: implications for functional nanodevices  

SciTech Connect

Using density functional theory, a series of calculations of structural and electronic properties of hydrogen vacancies in a fully hydrogenated boron nitride (fH-BN) layer were conducted. By dehydrogenating the fH-BN structure, B-terminated vacancies can be created which induce complete spin polarization around the Fermi level, irrespective of the vacancy size. On the contrary, the fH-BN structure with N-terminated vacancies can be a small-gap semiconductor, a typical spin gapless semiconductor, or a metal depending on the vacancy size. Utilizing such vacancy-induced band gap and magnetism changes, possible applications in spintronics are proposed, and a special fH-BN based quantum dot device is designed.

Zhou, Yungang; Wang, Zhiguo; Nie, JL; Yang, Ping; Sun, Xin; Khaleel, Mohammad A.; Zu, Xiaotao; Gao, Fei

2012-03-01T23:59:59.000Z

402

Energy transfer and 1.54 {mu}m emission in amorphous silicon nitride films  

Science Conference Proceedings (OSTI)

Er-doped amorphous silicon nitride films with various Si concentrations (Er:SiN{sub x}) were fabricated by reactive magnetron cosputtering followed by thermal annealing. The effects of Si concentrations and annealing temperatures were investigated in relation to Er emission and excitation processes. Efficient excitation of Er ions was demonstrated within a broad energy spectrum and attributed to disorder-induced localized transitions in amorphous Er:SiN{sub x}. A systematic optimization of the 1.54 {mu}m emission was performed and a fundamental trade-off was discovered between Er excitation and emission efficiency due to excess Si incorporation. These results provide an alternative approach for the engineering of sensitized Si-based light sources and lasers.

Yerci, S.; Li, R. [Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary's Street, Boston, Massachusetts 02215-2421 (United States); Kucheyev, S. O.; Buuren, T. van [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Basu, S. N. [Division of Materials Science and Engineering, Boston University, 15 Saint Mary's Street, Brookline, Massachusetts 02446 (United States); Department of Mechanical Engineering, Boston University, 110 Cummington Street, Boston, Massachusetts 02215 (United States); Dal Negro, L. [Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary's Street, Boston, Massachusetts 02215-2421 (United States); Division of Materials Science and Engineering, Boston University, 15 Saint Mary's Street, Brookline, Massachusetts 02446 (United States)

2009-07-20T23:59:59.000Z

403

Steel bonded dense silicon nitride compositions and method for their fabrication  

DOE Patents (OSTI)

A two-stage bonding technique for bonding high density silicon nitride and other ceramic materials to stainless steel and other hard metals, and multilayered ceramic-metal composites prepared by the technique are disclosed. The technique involves initially slurry coating a surface of the ceramic material at about 1500/sup 0/C in a vacuum with a refractory material and the stainless steel is then pressure bonded to the metallic coated surface by brazing it with nickel-copper-silver or nickel-copper-manganese alloys at a temperature in the range of about 850/sup 0/ to 950/sup 0/C in a vacuum. The two-stage bonding technique minimizes the temperature-expansion mismatch between the dissimilar materials.

Landingham, R.L.; Shell, T.E.

1985-05-20T23:59:59.000Z

404

Oxides and nitrides as alternative plasmonic materials in the optical range  

E-Print Network (OSTI)

As alternatives to conventional metals, new plasmonic materials offer many advantages in the rapidly growing fields of plasmonics and metamaterials. These advantages include low intrinsic loss, semiconductor-based design, compatibility with standard nanofabrication processes, tunability, and others. Transparent conducting oxides such as Al:ZnO, Ga:ZnO and indium-tin-oxide (ITO) enable many high-performance metamaterial devices operating in the near-IR. Transition-metal nitrides such as TiN or ZrN can be substitutes for conventional metals in the visible frequencies. In this paper we provide the details of fabrication and characterization of these new materials and discuss their suitability for a number of metamaterial and plasmonic applications.

Naik, Gururaj V; Boltasseva, Alexandra

2011-01-01T23:59:59.000Z

405

Dilute Group III-V nitride intermediate band solar cells with contact blocking layers  

DOE Patents (OSTI)

An intermediate band solar cell (IBSC) is provided including a p-n junction based on dilute III-V nitride materials and a pair of contact blocking layers positioned on opposite surfaces of the p-n junction for electrically isolating the intermediate band of the p-n junction by blocking the charge transport in the intermediate band without affecting the electron and hole collection efficiency of the p-n junction, thereby increasing open circuit voltage (V.sub.OC) of the IBSC and increasing the photocurrent by utilizing the intermediate band to absorb photons with energy below the band gap of the absorber layers of the IBSC. Hence, the overall power conversion efficiency of a IBSC will be much higher than an conventional single junction solar cell. The p-n junction absorber layers of the IBSC may further have compositionally graded nitrogen concentrations to provide an electric field for more efficient charge collection.

Walukiewicz, Wladyslaw (Kensington, CA); Yu, Kin Man (Lafayette, CA)

2012-07-31T23:59:59.000Z

406

Picosecond laser structuration under high pressures: Observation of boron nitride nanorods  

SciTech Connect

We report on picosecond UV-laser processing of hexagonal boron nitride (BN) at moderately high pressures above 500 bar. The main effect is specific to the ambient gas and laser pulse duration in the ablation regime: when samples are irradiated by 5 or 0.45 ps laser pulses in nitrogen gas environment, multiple nucleation of a new crystalline product-BN nanorods-takes place. This process is triggered on structural defects, which number density strongly decreases upon recrystallization. Nonlinear photon absorption by adsorbed nitrogen molecules is suggested to mediate the nucleation growth. High pressure is responsible for the confinement and strong backscattering of ablation products. A strong surface structuring also appears at longer 150 ps laser irradiation in similar experimental conditions. However, the transformed product in this case is amorphous strongly contaminated by boron suboxides B{sub x}O{sub y}.

Museur, Luc [Laboratoire de Physique des Lasers-LPL CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Petitet, Jean-Pierre; Kanaev, Andrei V. [Laboratoire d' Ingenierie des Materiaux et des Hautes Pressions-LIMHP CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Michel, Jean-Pierre [Laboratoire d' Ingenierie des Materiaux et des Hautes Pressions-LIMHP CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Laboratoire des Proprietes Mecaniques et Thermodynamiques des Materiaux-LPMTM CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Marine, Wladimir [Centre Interdisciplinaire de Nanoscience de Marseille-CINaM, UPR CNRS 3118, Faculte des Science de Luminy, 13288 Marseille (France); Anglos, Demetrios [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), 71110 Heraklion, Crete (Greece); Fotakis, Costas [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), 71110 Heraklion, Crete (Greece); Department of Physics, University of Crete, Heraklion, Crete (Greece)

2008-11-01T23:59:59.000Z

407

Evolution of oxidation and creep damage mechanisms in HIPed silicon nitride materials  

DOE Green Energy (OSTI)

Several yttria-fluxed, hot-isostatically pressed (HIPed) silicon nitrides have been tensile creep tested at temperatures representative of gas turbine engines. Creep and oxidation assisted damage mechanisms concurrently evolve when these materials are tested at high temperatures and low stresses (i.e., long exposure times at temperature). Atmospheric creep testing results in creation of oxygen and yttrium gradients across the radial dimension. High concentrations of oxygen and yttrium coincide with dense populations of lenticular-shaped cavities near the surface of crept specimens. The center of the tensile specimens was devoid of oxygen or yttrium; in addition, lenticular cavities were rare. The gradient in lenticular-cavity concentration is coincident with the oxygen and yttrium gradients. Stress corrosion cracking (SCC) also occurs in these HIPed silicon nitrides when they are subjected to stress at high temperatures in ambient air. The size of this damage zone increases when the temperature is higher and/or the applied stress is lower. Stress-corrosion cracking initiates at the surface of the tensile specimen and advances radially inwards. What nucleates SCC has not yet been identified, but it is believed to result from a stress-concentrator (e.g., machining damage) at the surface and its growth is a result of coalescence of microcracks and cavities. The higher concentration of oxygen and yttrium in the grain boundaries near the specimen`s surface lessens the local high temperature mechanical integrity; this is believed to be associated with the growth of the SCC zone. This SCC zone continues to grow in size during tensile loading until it reaches a critical size which causes fracture.

Wereszczak, A.A.; Ferber, M.K.; Kirkland, T.P.; More, K.L.

1994-10-01T23:59:59.000Z

408

Crystal and Electronic Structures of Neptunium Nitrides Synthesized Using a Fluoride Route  

SciTech Connect

A low-temperature fluoride route was utilized to synthesize neptunium mononitride, NpN. Through the development of this process, two new neptunium nitride species, NpN{sub 2} and Np{sub 2}N{sub 3}, were identified. The NpN{sub 2} and Np{sub 2}N{sub 3} have crystal structures isomorphous to those of UN{sub 2} and U{sub 2}N{sub 3}, respectively. NpN{sub 2} crystallizes in a face-centered cubic CaF{sub 2}-type structure with a space group of Fm3m and a refined lattice parameter of 5.3236(1) {angstrom}. The Np{sub 2}N{sub 3} adopts the body-centered cubic Mn{sub 2}O{sub 3}-type structure with a space group of Ia{bar 3}. Its refined lattice parameter is 10.6513(4) {angstrom}. The NpN synthesis at temperatures {le} 900 C using the fluoride route discussed here was also demonstrated. Previous computational studies of the neptunium nitride system have focused exclusively on the NpN phase because no evidence was reported experimentally on the presence of NpN{sub x} systems. Here, the crystal structures of NpN{sub 2} and Np{sub 2}N{sub 3} are discussed for the first time, confirming the experimental results by density functional calculations (DFT). These DFT calculations were performed within the local-density approximation (LDA+U) and the generalized-gradient approximation (GGA+U) corrected with an effective Hubbard parameter to account for the strong on-site Coulomb repulsion between Np 5f electrons. The effects of the spin-orbit coupling in the GGA+U calculations have also been investigated for NpN{sub 2} and NpN.

Silva, G W Chinthaka M [ORNL; Weck, Dr. Phil F. [Sandia National Laboratories (SNL); Eunja, Dr. Kim [University of Nevada, Las Vegas; Yeamans, Dr. Charles B. [Lawrence Livermore National Laboratory (LLNL); Cerefice, Gary S. [University of Nevada, Las Vegas; Sattelberger, Alfred P [Argonne National Laboratory (ANL); Czerwinski, Ken R. [University of Nevada, Las Vegas

2012-01-01T23:59:59.000Z

409

Nitrides I  

Science Conference Proceedings (OSTI)

May 24, 2010... Lincoln Laboratory, Lexington, MA, USA; Rajaram Bhat, Corning Inc ... Clemens Wächter1; Alexander Meyer1; Peter Michler1; 1Universität ...

410

Nitrides III  

Science Conference Proceedings (OSTI)

May 28, 2010... Lincoln Laboratory, Lexington, MA, USA; Rajaram Bhat, Corning Inc ... Jürgen Bläsing1; Armin Dadgar1; Thomas Hempel1; Peter Veit1; Alois ...

411

Bismuth in gallium arsenide: Structural and electronic properties of GaAs{sub 1-x}Bi{sub x} alloys  

Science Conference Proceedings (OSTI)

The structural and electronic properties of cubic GaAs{sub 1-x}Bi{sub x} alloys with bismuth concentration 0.0, 0.25, 0.50, 0.75 and 1.0 are studied using the 'special quasi-random structures' (SQS) approach of Zunger along with the generalized gradient approximation (GGA) and the Engel-Vosko generalized gradient approximation (EV-GGA). The lattice constant, bulk modulus, derivative of bulk modulus and energy gap vary with bismuth concentration nonlinearly. The present calculations show that the band gap decreases substantially with increasing bismuth concentration and that spin-orbit coupling influences the nature of bonding at high Bi concentrations. - Graphical abstract: Bowing effect of spin-orbit split-off band values versus Bi content with and without spin-orbit coupling for GaAs{sub 1-x}Bi{sub x} (at x=0.25, 0.50 and 0.75). Calculations are done with GGA. Highlights: Black-Right-Pointing-Pointer Structural and electronic properties of GaAs{sub 1-x}Bi{sub x} alloys were studied. Black-Right-Pointing-Pointer We present results of lattice constant, energy gap, bulk modulus and derivative. Black-Right-Pointing-Pointer The band gap decreases substantially with increasing Bi concentration. Black-Right-Pointing-Pointer Calculations of the density of states and charge densities are also presented. Black-Right-Pointing-Pointer We have performed calculations without and with spin-orbit coupling.

Reshak, Ali Hussain, E-mail: maalidph@yahoo.co.uk [School of Complex Systems, FFWP-South Bohemia University, Nove Hrady 37333 (Czech Republic); School of Material Engineering, Malaysia University of Perlis, P.O Box 77, d/a Pejabat Pos Besar, 01007 Kangar, Perlis (Malaysia); Kamarudin, H. [School of Material Engineering, Malaysia University of Perlis, P.O Box 77, d/a Pejabat Pos Besar, 01007 Kangar, Perlis (Malaysia); Auluck, S. [National Physical Laboratory Dr. KS Krishnan Marg, New Delhi 110012 (India); Kityk, I.V. [Electrical Engineering Department, Technological University of Czestochowa, Al. Armii Krajowej 17/19, Czestochowa (Poland)

2012-02-15T23:59:59.000Z

412

Unusual Room Temperature Ferromagnetism in Bulk Sintered GaP Doped with Copper  

Science Conference Proceedings (OSTI)

Robust room temperature ferromagnetism is obtained in single phase Gallium Phosphide doped with Cu{sup 2+} prepared by simple solid state reaction route. The saturation magnetization at 300 K is 1.5 times 10{sup -2} emu/g and the coercivity was found to be 125 Oe. A strong ferromagnetic resonance signal confirms the long range magnetic order which persists to temperatures as high as 739 K. X-ray absorption spectroscopy (XAS) indicate that Cu is in a +2 state. Ab initio calculations also show that the ferromagnetic ordering is energetically favorable in Cu doped GaP. When the spin-orbit coupling is included we get an enhanced total magnetic moment of 0.31 muB with a local moment on Cu 0.082 and on P 0.204 mu{sub B}. per atom.

Owens, F. J.; Gupta, A.; Rao, K. V.; Iqbal, Z.; Osorio Guillen, J. M.; Ahuja, R.; Guo, J.-H.

2007-06-01T23:59:59.000Z

413

N-polar III-nitride quantum well light-emitting diodes with polarization-induced doping  

Science Conference Proceedings (OSTI)

Nitrogen-polar III-nitride heterostructures present unexplored advantages over Ga(metal)-polar crystals for optoelectronic devices. This work reports N-polar III-nitride quantum-well ultraviolet light-emitting diodes grown by plasma-assisted molecular beam epitaxy that integrate polarization-induced p-type doping by compositional grading from GaN to AlGaN along N-face. The graded AlGaN layer simultaneously acts as an electron blocking layer while facilitating smooth injection of holes into the active region, while the built-in electric field in the barriers improves carrier injection into quantum wells. The enhanced doping, carrier injection, and light extraction indicate that N-polar structures have the potential to exceed the performance of metal-polar ultraviolet light-emitting diodes.

Verma, Jai; Simon, John; Protasenko, Vladimir; Kosel, Thomas; Xing, Huili Grace; Jena, Debdeep [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)

2011-10-24T23:59:59.000Z

414

Ion exchange separation of plutonium and gallium (1) resource and inventory requirements, (2) waste, emissions, and effluent, and (3) facility size  

SciTech Connect

The following report summarizes an effort intended to estimate within an order-of-magnitude the (1) resource and inventory requirements, (2) waste, emissions, and effluent amounts, and (3) facility size, for ion exchange (IX) separation of plutonium and gallium. This analysis is based upon processing 3.5 MT-Pu/yr. The technical basis for this summary is detailed in a separate document, {open_quotes}Preconceptual Design for Separation of Plutonium and Gallium by Ion Exchange{close_quotes}. The material balances of this separate document are based strictly on stoichiometric amounts rather than details of actual operating experience, in order to avoid classification as Unclassified Controlled Nuclear Information. This approximation neglets the thermodynamics and kinetics which can significantly impact the amount of reagents required. Consequently, the material resource requirements and waste amounts presented here would normally be considered minimums for processing 3.5 MT-Pu/yr; however, the author has compared the inventory estimates presented with that of an actual operating facility and found them similar. Additionally, the facility floor space presented here is based upon actual plutonium processing systems and can be considered a nominal estimate.

DeMuth, S.

1997-09-30T23:59:59.000Z

415

Bulk and surface controlled diffusion of fission gas atoms  

Science Conference Proceedings (OSTI)

Fission gas retention and release impact nuclear fuel performance by, e.g., causing fuel swelling leading to mechanical interaction with the clad, increasing the plenum pressure and reducing the gap thermal conductivity. All of these processes are important to understand in order to optimize operating conditions of nuclear reactors and to simulate accident scenarios. Most fission gases have low solubility in the fuel matrix, which is especially pronounced for large fission gas atoms such as Xe and Kr, and as a result there is a significant driving force for segregation of gas atoms to extended defects such as grain boundaries or dislocations and subsequently for nucleation of gas bubbles at these sinks. Several empirical or semi-empirical models have been developed for fission gas release in nuclear fuels, e.g. [1-6]. One of the most commonly used models in fuel performance codes was published by Massih and Forsberg [3,4,6]. This model is similar to the early Booth model [1] in that it applies an equivalent sphere to separate bulk UO{sub 2} from grain boundaries represented by the sphere circumference. Compared to the Booth model, it also captures trapping at grain boundaries, fission gas resolution and it describes release from the boundary by applying timedependent boundary conditions to the circumference. In this work we focus on the step where fission gas atoms diffuse from the grain interior to the grain boundaries. The original Massih-Forsberg model describes this process by applying an effective diffusivity divided into three temperature regimes. In this report we present results from density functional theory calculations (DFT) that are relevant for the high (D{sub 3}) and intermediate (D{sub 2}) temperature diffusivities of fission gases. The results are validated by making a quantitative comparison to Turnbull's [8-10] and Matzke's data [12]. For the intrinsic or high temperature regime we report activation energies for both Xe and Kr diffusion in UO{sub 2{+-}x}, which compare favorably to available experiments. This is an extension of previous work [13]. In particular, it applies improved chemistry models for the UO{sub 2{+-}x} nonstoichiometry and its impact on the fission gas activation energies. The derivation of these models follows the approach that used in our recent study of uranium vacancy diffusion in UO{sub 2} [14]. Also, based on the calculated DFT data we analyze vacancy enhanced diffusion mechanisms in the intermediate temperature regime. In addition to vacancy enhanced diffusion we investigate species transport on the (111) UO{sub 2} surface. This is motivated by the formation of small voids partially filled with fission gas atoms (bubbles) in UO{sub 2} under irradiation, for which surface diffusion could be the rate-limiting transport step. Diffusion of such bubbles constitutes an alternative mechanism for mass transport in these materials.

Andersson, Anders D. [Los Alamos National Laboratory

2012-08-09T23:59:59.000Z

416

Application of Self-Propagating High Temperature Synthesis to the Fabrication of Actinide Bearing Nitride and Other Ceramic Nuclear Fuels  

Science Conference Proceedings (OSTI)

The high vapor pressures of americium (Am) and americium nitride (AmN) are cause for concern in producing nitride ceramic nuclear fuel that contains Am. Along with the problem of Am retention during the sintering phases of current processing methods, are additional concerns of producing a consistent product of desirable homogeneity, density and porosity. Similar difficulties have been experienced during the laboratory scale process development stage of producing metal alloys containing Am wherein compact powder sintering methods had to be abandoned. Therefore, there is an urgent need to develop a low-temperature or low–heat fuel fabrication process for the synthesis of Am-containing ceramic fuels. Self-propagating high temperature synthesis (SHS), also called combustion synthesis, offers such an alternative process for the synthesis of Am nitride fuels. Although SHS takes thermodynamic advantage of the high combustion temperatures of these exothermic SHS reactions to synthesize the required compounds, the very fast heating, reaction and cooling rates can kinetically generate extremely fast reaction rates and facilitate the retention of volatile species within the rapidly propagating SHS reaction front. The initial objective of the research program is to use Mn as the surrogate for Am to synthesize a reproducible, dense, high quality Zr-Mn-N ceramic compound. Having determined the fundamental SHS reaction parameters and optimized SHS processing steps using Mn as the surrogate for Am, the technology will be transferred to Idaho National Laboratory to successfully synthesize a high quality Zr-Am-N ceramic fuel.

John J. Moore, Douglas E. Burkes, Collin D. Donohoue, Marissa M. Reigel, J. Rory Kennedy

2009-05-18T23:59:59.000Z

417

Understanding Bulk Power Reliability: The Importance of Good Data and A Critical Review of Existing Sources  

NLE Websites -- All DOE Office Websites (Extended Search)

Understanding Bulk Power Reliability: Understanding Bulk Power Reliability: The Importance of Good Data and A Critical Review of Existing Sources Emily Fisher Lawrence Berkeley National Laboratory esfisher@lbl.gov Joseph H. Eto Lawrence Berkeley National Laboratory jheto@lbl.gov Kristina Hamachi LaCommare Lawrence Berkeley National Laboratory kshamachi@lbl.gov Abstract Bulk power system reliability is of critical importance to the electricity sector. Complete and accurate information on events affecting the bulk power system is essential for assessing trends and efforts to maintain or improve reliability. Yet, current sources of this information were not designed with these uses in mind. They were designed, instead, to support real-time emergency notification to industry and government first-responders. This

418

Improvements in Shortwave Bulk Scattering and Absorption Models for the Remote Sensing of Ice Clouds  

Science Conference Proceedings (OSTI)

This study summarizes recent improvements in the development of bulk scattering/absorption models at solar wavelengths. The approach combines microphysical measurements from various field campaigns with single-scattering properties for nine habits ...

Bryan A. Baum; Ping Yang; Andrew J. Heymsfield; Carl G. Schmitt; Yu Xie; Aaron Bansemer; Yong-Xiang Hu; Zhibo Zhang

2011-05-01T23:59:59.000Z

419

Modifying a Mesoscale Meteorological Model to Better Incorporate Urban Heat Storage: A Bulk-Parameterization Approach  

Science Conference Proceedings (OSTI)

A simple bulk-parameterization scheme is implemented in modifying a mesoscale meteorological model to better incorporate urban heat storage. The objective is to improve the quantification of the fluxes associated with heat storage change and to ...

Haider Taha

1999-04-01T23:59:59.000Z

420

Predicting the Snow-to-Liquid Ratio of Surface Precipitation Using a Bulk Microphysics Scheme  

Science Conference Proceedings (OSTI)

Bulk microphysics parameterizations play an increasingly important role for quantitative precipitation forecasting (QPF) in operational numerical weather prediction (NWP). For wintertime, numerical prediction of snowfall amounts is done by ...

J. A. Milbrandt; A. Glazer; D. Jacob

2012-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

In-situ Tracking of Slip Activation in Bulk Polycrystalline Zirconium  

Science Conference Proceedings (OSTI)

Presentation Title, In-situ Tracking of Slip Activation in Bulk Polycrystalline Zirconium. Author(s), J. Lind, S. F. Li, C. M. Hefferan, R. Pokharel, A. D. Rollett, ...

422

arXiv.org help - arXiv Bulk Data Access  

NLE Websites -- All DOE Office Websites (Extended Search)

This is the preferred way to bulk-download or keep an up-to-date copy of arXiv metadata. API arXiv supports real-time programmatic access to metadata and our search engine via the...

423

Bulk Hydrometeor Classification and Quantification Using Polarimetric Radar Data: Synthesis of Relations  

Science Conference Proceedings (OSTI)

A new synthesis of information forming the foundation for rule-based systems to deduce dominant bulk hydrometeor types and amounts using polarimetric radar data is presented. The information is valid for a 10-cm wavelength and consists of ...

Jerry M. Straka; Dusan S. Zrni?; Alexander V. Ryzhkov

2000-08-01T23:59:59.000Z

424

Comparison of etch characteristics of KOH, TMAH and EDP for bulk micromachining of silicon (110)  

Science Conference Proceedings (OSTI)

Bulk micromachining in Si (110) wafer is an essential process for fabricating vertical microstructures by wet chemical etching. We compared the anisotropic etching properties of potassium hydroxide (KOH), tetra-methyl ammonium hydroxide (TMAH) and ethylene ...

Shankar Dutta; Md Imran; P. Kumar; R. Pal; P. Datta; R. Chatterjee

2011-10-01T23:59:59.000Z

425

A Rapid-Circulation Evaporation Chamber for Measuring Bulk Stomatal Resistance  

Science Conference Proceedings (OSTI)

A relatively simple method is described for determining evaporation of short vegetation at any moment of time. The method is based on the measurement of bulk stomatal resistance of the crop with an evaporation chamber. Once this quantity is known,...

W. Kohsiek

1981-01-01T23:59:59.000Z

426

A Probabilistic Bulk Model of Coupled Mixed Layer and Convection. Part II: Shallow Convection Case  

Science Conference Proceedings (OSTI)

The probabilistic bulk convection model (PBCM) developed in a companion paper is here extended to shallow nonprecipitating convection. The PBCM unifies the clear-sky and shallow convection boundary layer regimes by obtaining mixed-layer growth, ...

Pierre Gentine; Alan K. Betts; Benjamin R. Lintner; Kirsten L. Findell; Chiel C. van Heerwaarden; Fabio D’Andrea

2013-06-01T23:59:59.000Z

427

A Binned Approach to Cloud-Droplet Riming Implemented in a Bulk Microphysics Model  

Science Conference Proceedings (OSTI)

This paper presents the development and application of a binned approach to cloud-droplet riming within a bulk microphysics model. This approach provides a more realistic representation of collision–coalescence that occurs between ice and cloud ...

Stephen M. Saleeby; William R. Cotton

2008-02-01T23:59:59.000Z

428

Stability of Ni-Nb-based and Zr-based bulk metallic glasses against environmental degradation.  

E-Print Network (OSTI)

???The ternary (Ni8Nb5)99.5Sb0.5 bulk metallic glass (BMG) was synthesized in this thesis and the corrosion, oxidation and high temperature induced crystallization behaviors are investigated. The… (more)

Lü, Junxia (???)

2009-01-01T23:59:59.000Z

429

Investigation of Propane and Methane Bulk Properties Structure Using Two Different Force Fields  

Science Conference Proceedings (OSTI)

Some structural properties of propane and methane bulk system in liquid phase have been estimated using molecular dynamics calculations on the EGEE Grid infrastucture. The effect of adopting two different force fields, OPLS/AMBER and Dreiding, has been ...

Alessandro Costantini; Antonio Laganŕ

2008-06-01T23:59:59.000Z

430

,"U.S. Refinery, Bulk Terminal, and Natural Gas Plant Stocks...  

U.S. Energy Information Administration (EIA) Indexed Site

S1","MDGSXUS1","MRESXUS1","MPRSXUS1" "Date","U.S. Finished Motor Gasoline Stocks at Refineries, Bulk Terminals, and Natural Gas Plants (Thousand Barrels)","U.S. Reformulated Motor...

431

Improved Radiative Transfer Calculations from Information Provided by Bulk Microphysical Schemes  

Science Conference Proceedings (OSTI)

Bulk microphysical schemes are providing increasingly detailed information of hydrometeor profiles both within and below clouds. This information can be used to improve radiative transfer calculations with little increase in computation time. In ...

J. C. Petch

1998-05-01T23:59:59.000Z

432

An Estimation of the Bulk Transfer Coefficients for a Bare Soil Surface Using a Linear Model  

Science Conference Proceedings (OSTI)

A linear heat budget model is developed to estimate the daytime means of the bulk transfer coefficients for heat and evaporation efficiency using the daily variation of observational data. The daily variation of shortwave radiation, ground-level ...

Dai Matsushima; Junsei Kondo

1995-04-01T23:59:59.000Z

433

A Double-Moment Multiple-Phase Four-Class Bulk Ice Scheme. Part I: Description  

Science Conference Proceedings (OSTI)

A detailed ice-phase bulk microphysical scheme has been developed for simulating the hydrometeor distributions of convective and stratiform precipitation in different large-scale environmental conditions. The proposed scheme involves 90 distinct ...

Brad Schoenberg Ferrier

1994-01-01T23:59:59.000Z

434

Tracer Transport in Deep Convective Updrafts: Plume Ensemble versus Bulk Formulations  

Science Conference Proceedings (OSTI)

Two widely used approaches for parameterizing tracer transport based on convective mass fluxes are the plume ensemble formulation (PEF) and the bulk formulation (BF). Here the behavior of these two is contrasted for the specific case in which the ...

Mark G. Lawrence; Philip J. Rasch

2005-08-01T23:59:59.000Z

435

U.S. Refinery Grade Butane Stocks at Bulk Terminals (Thousand ...  

U.S. Energy Information Administration (EIA)

U.S. Refinery Grade Butane Stocks at Bulk Terminals (Thousand Barrels) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9; ...

436

U.S. Refinery Grade Butane Stocks at Bulk Terminals (Thousand ...  

U.S. Energy Information Administration (EIA)

U.S. Refinery Grade Butane Stocks at Bulk Terminals (Thousand Barrels) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec; 2005: 1,077: 999: 1,362: ...

437

A Method for Adaptive Habit Prediction in Bulk Microphysical Models. Part I: Theoretical Development  

Science Conference Proceedings (OSTI)

Bulk microphysical schemes use the capacitance model for ice vapor growth in combination with mass–size relationships to determine the evolution of ice water content (IWC) and ice particle maximum dimension in time. These approaches are limited ...

Jerry Y. Harrington; Kara Sulia; Hugh Morrison

2013-02-01T23:59:59.000Z

438

A New Bulk Microphysical Scheme That Includes Riming Intensity and Temperature-Dependent Ice Characteristics  

Science Conference Proceedings (OSTI)

A new bulk microphysical parameterization (BMP) scheme is presented that includes a diagnosed riming intensity and its impact on ice characteristics. As a result, the new scheme represents a continuous spectrum from pristine ice particles to ...

Yanluan Lin; Brian A. Colle

2011-03-01T23:59:59.000Z

439

A New Bulk Shallow-Cumulus Model and Implications for Penetrative Entrainment Feedback on Updraft Buoyancy  

Science Conference Proceedings (OSTI)

A new refinement of Albrecht et al.’s bulk model for shallow-cumulus convection is presented. It is used to illuminate fundamental aspects of oceanic shallow-cumulus boundary layer structure, including updraft buoyancy and vertical velocity ...

Christopher S. Bretherton; Sungsu Park

2008-07-01T23:59:59.000Z

440

Residential Bulk-Fed Wood-Pellet Central Boilers and Furnace Rebate Program  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Residential Bulk-Fed Wood-Pellet Central Boilers and Furnace Rebate Residential Bulk-Fed Wood-Pellet Central Boilers and Furnace Rebate Program Residential Bulk-Fed Wood-Pellet Central Boilers and Furnace Rebate Program < Back Eligibility Multi-Family Residential Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Maximum Rebate $6,000 Program Info Funding Source New Hampshire Renewable Energy Fund (FY 2013) Start Date 04/14/2010 Expiration Date When progr State New Hampshire Program Type State Rebate Program Rebate Amount 30% Provider New Hampshire Public Utilities Commission The New Hampshire Public Utilities Commission (PUC) is offering rebates of 30% of the installed cost of qualifying new residential bulk-fed, wood-pellet central heating boilers or furnaces. The maximum rebate is $6,000. To qualify, systems must (1) become operational on or after May 1,

Note: This page contains sample records for the topic "bulk gallium nitride" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

High-Energy, Low-Frequency Risk to the North American Bulk Power System  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

High-Energy, Low-Frequency Risk to the North American Bulk Power High-Energy, Low-Frequency Risk to the North American Bulk Power System (June 2010) High-Energy, Low-Frequency Risk to the North American Bulk Power System (June 2010) A Jointly-Commissioned Summary Report of the North American Electric Reliability Corporation and the U.S. Department of Energy's November 2009 Workshop. The North American Electric Reliability Corporation (NERC) and the U.S. Department of Energy (DOE) partnered in July of 2009 on an effort to address High-Impact, Low-Frequency risks to the North American bulk power system. In August, NERC formed a steering committee made up of industry and risk experts to lead the development of an initial workshop on the subject, chaired by Scott Moore, VP Transmission System & Region Operations for American Electric Power, and Robert Stephan, Former Assistant Secretary for

442

Corrosion and Cytotoxicity of a Ni-free Zr-Al-Fe-Cu Bulk Metallic Glass  

Science Conference Proceedings (OSTI)

Corrosion resistance was studied using polarization technique in phosphate buffered saline solution ... Cell viability, adhesion, morphology, and proliferation of osteoblasts, endothelial cells and .... Joining of Active Bulk Metallic Glasses in Air.

443

Which Bulk Aerodynamic Algorithms are Least Problematic in Computing Ocean Surface Turbulent Fluxes?  

Science Conference Proceedings (OSTI)

Bulk aerodynamic algorithms are needed to compute ocean surface turbulent fluxes in weather forecasting and climate models and in the development of global surface flux datasets. Twelve such algorithms are evaluated and ranked using direct ...

Michael A. Brunke; Chris W. Fairall; Xubin Zeng; Laurence Eymard; Judith A. Curry

2003-02-01T23:59:59.000Z

444

An End-to-End QoS Mechanism for Grid Bulk Data Transfer for Supporting Virtualization  

E-Print Network (OSTI)

An End-to-End QoS Mechanism for Grid Bulk Data Transfer for Supporting Virtualization Kashif Munir1 for Grid bulk data transfers. Our mechanism enables per-flow guarantees and efficiently utilizes available: Quality of Service, QoS, Grid, Bulk Data Transfer, Advance Reservation, UDT 1 Introduction Grid computing

Welzl, Michael

445

Bulk Electricity System Impacts of Distributed and Transmission System Connected Solar PV  

Science Conference Proceedings (OSTI)

This report describes research examining how increased levels of photovoltaic (PV) can impact the bulk electricity system. Previous modeling of both bulk and distributed systems was extended to include more realistic assumptions, further sensitivities, and greater explanation of results. It was shown that high penetrations of distributed PV without low-voltage ride-through (LVRT) will increase voltage recovery time after a fault. The impact is exacerbated when the potential for residential ac ...

2012-12-31T23:59:59.000Z

446

Vibration-Induced Conductivity Fluctuation Measurement for Soil Bulk Density Analysis  

E-Print Network (OSTI)

Soil bulk density affects water storage, water and nutrient movement, and plant root activity in the soil profile. Its measurement is difficult in field conditions. Vibration-induced conductivity fluctuation was investigated to quantify soil bulk density with possible field applications in the future. The AC electrical conductivity of soil was measured using a pair of blade-like electrodes while exposing the soil to periodic vibration. The blades were positioned longitudinally and transversally to the direction of the induced vibration to enable the calculation of a normalized index. The normalized index was expected to provide data independent from the vibration strength and to reduce the effect of soil salinity and water content. The experiment was conducted on natural and salinized fine sand at two moisture conditions and four bulk densities. The blade-shaped electrodes improved electrode-soil contact compared to cylindrical electrodes, and thereby, reduced measurement noise. Simulations on a simplified resistor lattice indicate that the transversal effect increases as soil bulk density decreases. Measurement of dry sand showed a negative correlation between the normalized conductivity fluctuation and soil bulk density for both longitudinal and transversal settings. The decrease in the transversal signal was smaller than expected. The wet natural and salinized soils performed very similarly as hypothesized, but their normalized VICOF response was not significant to bulk density changes.

Andrea Sz. Kishne; Cristine L. S. Morgan; Hung-Chih Chang; Laszlo B. Kish

2007-05-03T23:59:59.000Z

447

Methods for and products of processing nanostructure nitride, carbonitride and oxycarbonitride electrode power materials by utilizing sol gel technology for supercapacitor applications  

SciTech Connect

Metal nitride, carbonitride, and oxycarbonitride powder with high surface area (up to 150 m.sup.2 /g) is prepared by using sol-gel process. The metal organic precursor, alkoxides or amides, is synthesized firstly. The metal organic precursor is modified by using unhydrolyzable organic ligands or templates. A wet gel is formed then by hydrolysis and condensation process. The solvent in the wet gel is then be removed supercritically to form porous amorphous hydroxide. This porous hydroxide materials is sintered to 725.degree. C. under the ammonia flow and porous nitride powder is formed. The other way to obtain high surface area nitride, carbonitride, and oxycarbonitride powder is to pyrolyze polymerized templated metal amides aerogel in an inert atmosphere. The electrochemical capacitors are prepared by using sol-gel prepared nitride, carbonitride, and oxycarbonitride powder. Two methods are used to assemble the capacitors. Electrode is formed either by pressing the mixture of nitride powder and binder to a foil, or by depositing electrode coating onto metal current collector. The binder or coating is converted into a continuous network of electrode material after thermal treatment to provide enhanced energy and power density. Liquid electrolyte is soaked into porous electrode. The electrochemical capacitor assembly further has a porous separator layer between two electrodes/electrolyte and forming a unit cell.

Huang, Yuhong (West Hills, CA); Wei, Oiang (West Hills, CA); Chu, Chung-tse (Chatsworth, CA); Zheng, Haixing (Oak Park, CA)

2001-01-01T23:59:59.000Z

448

Multi-scale modelling of III-nitrides: from dislocations to the electronic structure  

E-Print Network (OSTI)

in bulk . . . . . . . . . . . . . . . . . . . . . . . 28 2.3.3 Dislocation types near the free surface . . . . . . . . . . . . . . . . 31 2.4 Beyond linear elasticity – energy of the dislocation core . . . . . . . . . . 33 2.5 Summary... emitting blue light (? = 405 nm), more data (up to ? 25 GB) could be written on every single disk due to the shorter wavelength of the writing beam. Other exciting applications include solar cell arrays for satellites and power amplifiers at microwave...

Holec, David

449

Influence of nitrogen background pressure on structure of niobium nitride films grown by pulsed laser deposition  

SciTech Connect

Depositions of niobium nitride thin films on Nb using pulsed laser deposition (PLD) with different nitrogen background pressures (10.7 to 66.7 Pa) have been performed. The effect of nitrogen pressure on NbN formation in this process was examined. The deposited films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), and energy dispersive X-ray (EDX) analysis. Hexagonal {beta}-Nb{sub 2}N and cubic {delta}-NbN phases resulted when growth was performed in low nitrogen background pressures. With an increase in nitrogen pressure, NbN films grew in single hexagonal {beta}-Nb{sub 2}N phase. The formation of the hexagonal texture during the film growth was studied. The c/a ratio of the hexagonal {beta}-Nb{sub 2}N unit cell parameter increases with increasing nitrogen pressure. Furthermore, the N:Nb ratio has a strong influence on the lattice parameter of the {delta}-NbN, where the highest value was achieved for this ratio was 1.19. It was found that increasing nitrogen background pressure leads to change in the phase structure of the NbN film. With increasing nitrogen pressure, the film structure changes from hexagonal to a mixed phase and then back to a hexagonal phase.

Ashraf H. Farha, Ali O. Er, Yüksel Ufuktepe, Ganapati Myneni, Hani E. Elsayed-Ali

2011-12-01T23:59:59.000Z

450

High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films  

Science Conference Proceedings (OSTI)

A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

R. Farrell; V. R. Pagan; A. Kabulski; Sridhar Kuchibhatl; J. Harman; K. R. Kasarla; L. E. Rodak; P. Famouri; J. Peter Hensel; D. Korakakis

2008-05-01T23:59:59.000Z

451

High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films  

Science Conference Proceedings (OSTI)

A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE-grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

Farrell, R.; Pagan, V.R.; Kabulski, A.; Kuchibhatla, S.; Harman, J.; Kasarla, K.R.; Rodak, L.E.; Hensel, J.P.; Famouri, P.; Korakakis, D.

2008-01-01T23:59:59.000Z

452

Structure and composition of nanometer-sized nitrides in a creep resistant cast austenitic alloy  

SciTech Connect

The microstructure of a new and improved high-temperature creep-resistant cast austenitic alloy, CF8C-Plus, was characterized after creep-rupture testing at 1023 K (750 C) and 100 MPa. Microstructures were investigated by detailed scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy (EDS). Principal component analysis of EDS spectrum images was used to examine the complex precipitate morphology. Thermodynamic modeling was performed to predict equilibrium phases in this alloy as well as the compositions of these phases at relevant temperatures. The improved high-temperature creep strength of CF8C-Plus over its predecessor CF8C is suggested to be due to the modified microstructure and phase stability in the alloy, including the absence of {delta}-ferrite in the as-cast condition and the development of a stable, slow-growing precipitation hardening nitride phase - the tetragonal Z-phase - which has not been observed before in cast austenitic stainless steels.

Evans, Neal D [ORNL; Maziasz, Philip J [ORNL; Shingledecker, John P. [Electric Power Research Institute (EPRI); Pollard, Michael J [Caterpillar Technical Center

2010-01-01T23:59:59.000Z

453

Carbide/nitride grain refined rare earth-iron-boron permanent magnet and method of making  

DOE Patents (OSTI)

A method of making a permanent magnet wherein 1) a melt is formed having a base alloy composition comprising RE, Fe and/or Co, and B (where RE is one or more rare earth elements) and 2) TR (where TR is a transition metal selected from at least one of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Al) and at least one of C and N are provided in the base alloy composition melt in substantially stoichiometric amounts to form a thermodynamically stable compound (e.g. TR carbide, nitride or carbonitride). The melt is rapidly solidified in a manner to form particulates having a substantially amorphous (metallic glass) structure and a dispersion of primary TRC, TRN and/or TRC/N precipitates. The amorphous particulates are heated above the crystallization temperature of the base alloy composition to nucleate and grow a hard magnetic phase to an optimum grain size and to form secondary TRC, TRN and/or TRC/N precipitates dispersed at grain boundaries. The crystallized particulates are consolidated at an elevated temperature to form a shape. During elevated temperature consolidation, the primary and secondary precipitates act to pin the grain boundaries and minimize deleterious grain growth that is harmful to magnetic properties.

McCallum, R. William (Ames, IA); Branagan, Daniel J. (Ames, IA)

1996-01-23T23:59:59.000Z

454

Antifuse with a single silicon-rich silicon nitride insulating layer  

DOE Patents (OSTI)

An antifuse is disclosed which has an electrically-insulating region sandwiched between two electrodes. The electrically-insulating region has a single layer of a non-hydrogenated silicon-rich (i.e. non-stoichiometric) silicon nitride SiN.sub.X with a nitrogen content X which is generally in the range of 0

Habermehl, Scott D.; Apodaca, Roger T.

2013-01-22T23:59:59.000Z

455

Aerosol Impacts on Clouds and Precipitation in Eastern China: Results from Bin and Bulk Microphysics  

Science Conference Proceedings (OSTI)

Using the Weather Research and Forecasting (WRF) model coupled with a 3 spectral-bin microphysics ('SBM') and measurements from the Atmospheric Radiation 4 Measurement (ARM) Mobile Facility field campaign in China (AMF-China), the authors 5 examine aerosol indirect effects (AIE) in the typical cloud regimes of the warm and cold 6 seasons in Southeast China: deep convective clouds (DCC) and stratus clouds (SC), 7 respectively. Comparisons with a two-moment bulk microphysics ('Bulk') are performed 8 to gain insights for improving bulk schemes in estimating AIE in weather and climate 9 simulations. For the first time, measurements of aerosol and cloud properties acquired in 10 China are used to evaluate model simulations to better understand AIE in China. It is 11 found that changes in cloud condensation nuclei (CCN) concentration significantly 12 change the timing of storms, the spatial and temporal distributions of precipitation, the 13 frequency distribution of precipitation rate, as well as cloud base and top heights for the 14 DCC, but not for the SC. CCN increase cloud droplet number (Nc) and mass 15 concentrations, decrease raindrop number concentration (Nr), and delay the onset of 16 precipitation. It is indicated much higher Nc and the opposite CCN effects on convection 17 and heavy rain with Bulk compared to SBM stem from the fixed CCN prescribed in Bulk. 18 CCN have a significant effect on ice microphysical properties with SBM but not Bulk 19 and different condensation/deposition freezing parameterizations employed could be the 20 main reason. This study provided insights to further improve the bulk scheme to better 21 account for aerosol-cloud interactions in regional and global climate simulations, which 22 will be the focus for a follow-on paper.

Fan, Jiwen; Leung, Lai-Yung R.; Li, Zhanqing; Morrison, H.; Chen, Hongbin; Zhou, Yuquan; Qian, Yun; Wang, Yuan

2012-01-19T23:59:59.000Z

456

Highest transmittance and high-mobility amorphous indium gallium zinc oxide films on flexible substrate by room-temperature deposition and post-deposition anneals  

Science Conference Proceedings (OSTI)

Amorphous indium gallium zinc oxide (a-IGZO) thin films of the highest transmittance reported in literature were initially deposited onto flexible polymer substrates at room temperature. The films were annealed in vacuum, air, and oxygen to enhance their electrical and optical performances. Electrical and optical characterizations were done before and after anneals. A partial reversal of the degradation in electrical properties upon annealing in oxygen was achieved by subjecting the films to subsequent vacuum anneals. A model was developed based on film texture and structural defects which showed close agreement between the measured and calculated carrier mobility values at low carrier concentrations (2-6 x 10{sup 19} cm{sup -3}).

Gadre, Mandar J. [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States); Alford, T. L. [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States); Flexible Display Center at Arizona State University, Tempe, Arizona 85284 (United States)

2011-08-01T23:59:59.000Z

457

Effects of Bulk and Surface Conductivity on the Performance of CdZnTe Pixel Detectors  

E-Print Network (OSTI)

We studied the effects of bulk and surface conductivity on the performance of high-resistivity CdZnTe (CZT) pixel detectors with Pt contacts. We emphasize the difference in mechanisms of the bulk and surface conductivity as indicated by their different temperature behaviors. In addition, the existence of a thin (10-100 A) oxide layer on the surface of CZT, formed during the fabrication process, affects both bulk and surface leakage currents. We demonstrate that the measured I-V dependencies of bulk current can be explained by considering the CZT detector as a metal-semiconductor-metal system with two back-to-back Schottky-barrier contacts. The high surface leakage current is apparently due to the presence of a low-resistivity surface layer that has characteristics which differ considerably from those of the bulk material. This surface layer has a profound effect on the charge collection efficiency in detectors with multi-contact geometry; some fraction of the electric field lines originated on the cathode int...

Bolotnikov, A E; Cook, W R; Harrison, F A; Kuvvetli, I; Schindler, S; Bolotnikov, Aleksey E.; Cook, Walter R.; Harrison, Fiona A.; Kuvvetli, Irfan; Schindler, Stephen M.

2001-01-01T23:59:59.000Z

458

Bulk scalar field in the braneworld can mimic the 4D inflaton dynamics  

E-Print Network (OSTI)

Based on the recently proposed scenario of inflation driven by a bulk scalar field in the braneworld of the Randall-Sundrum (RS) type, we investigate the dynamics of a bulk scalar field on the inflating braneworld. We derive the late time behavior of the bulk scalar field by analyzing the property of the retarded Green function. We find that the late time behavior is basically dominated by a single (or a pair of) pole(s) in the Green function irrespective of the initial condition and of the signature of $m^{2}=V''(\\phi)$, where $V(\\phi)$ is the potential of the bulk scalar field. Including the lowest order back-reaction to the geometry, this late time behavior can be well approximated by an effective 4-dimensional scalar field with $m^2_{\\mathrm{eff}}=m^2/2$. The mapping to the 4-dimensional effective theory is given by a simple scaling of the potential with a redefinition of the field. Our result supports the picture that the scenario of inflation driven by a bulk scalar field works in a quite similar way to that in the standard 4-dimensional cosmology.

Yoshiaki Himemoto; Takahiro Tanaka; Misao Sasaki

2001-12-12T23:59:59.000Z

459

Understanding Bulk Power Reliability: The Importance of Good Data and A  

NLE Websites -- All DOE Office Websites (Extended Search)

Understanding Bulk Power Reliability: The Importance of Good Data and A Understanding Bulk Power Reliability: The Importance of Good Data and A Critical Review of Existing Sources Title Understanding Bulk Power Reliability: The Importance of Good Data and A Critical Review of Existing Sources Publication Type Report Year of Publication 2012 Authors Fisher, Emily, Joseph H. Eto, and Kristina Hamachi LaCommare Pagination 11 Date Published 01/2012 Publisher LBNL City Berkeley Keywords electricity markets and policy group, energy analysis and environmental impacts department, power system reliability, power system reliability metrics, transmission system reliability Abstract Bulk power system reliability is of critical importance to the electricity sector. Complete and accurate information on events affecting the bulk power system is essential for assessing trends and efforts to maintain or improve reliability. Yet, current sources of this information were not designed with these uses in mind. They were designed, instead, to support real-time emergency notification to industry and government first-responders. This paper reviews information currently collected by both industry and government sources for this purpose and assesses factors that might affect their usefulness in supporting the academic literature that has relied upon them to draw conclusions about the reliability of the US electric power system.

460

Three Alkali-Metal-Gold-Gallium Systems. Ternary Tunnel Structures and Some Problems with Poorly Ordered Cations  

SciTech Connect

Six new intermetallic compounds have been characterized in the alkali metal (A = Na, Rb, Cs)–gold–gallium systems. Three isostructural compounds with the general composition A0.55Au2Ga2, two others of AAu3Ga2 (A = Rb, Cs), and the related Na13Au41.2Ga30.3 were synthesized via typical high-temperature reactions and their crystal structures determined by single-crystal X-ray diffraction analysis: Na0.56(9)Au2Ga2 (I, I4/mcm, a = 8.718(1) Ĺ, c = 4.857(1) Ĺ, Z = 4), Rb0.56(1)Au2Ga2 (II, I4/mcm, a = 8.950(1) Ĺ, c = 4.829(1) Ĺ, Z = 4), Cs0.54(2)Au2Ga2 (III, I4/mcm, a = 9.077(1) Ĺ, c = 4.815(1) Ĺ, Z = 4), RbAu3Ga2 (IV, Pnma, a = 13.384(3) Ĺ, b = 5.577(1) Ĺ, c = 7.017(1) Ĺ, Z = 4), CsAu3Ga2 (V, Pnma, a = 13.511(3) Ĺ, b = 5.614(2) Ĺ, c = 7.146(1) Ĺ, Z = 4), Na13Au41.2(1)Ga30.3(1) (VI, P6 mmm, a = 19.550(3) Ĺ, c = 8.990(2) Ĺ, Z = 2). The first three compounds (I–III) are isostructural with tetragonal K0.55Au2Ga2 and likewise contain planar eight-member Au/Ga rings that stack along c to generate tunnels and that contain varying degrees of disordered Na–Cs cations. The cation dispositions are much more clearly and reasonably defined by electron density mapping than through least-squares refinements with conventional anisotropic ellipsoids. Orthorhombic AAu3Ga2 (IV, V) are ordered ternary Rb and Cs derivatives of the SrZn5 type structure, demonstrating structural variability within the AAu3Ga2 family. All attempts to prepare an isotypic “NaAu3Ga2” were not successful, but yielded only a similar composition Na13Au41.2Ga30.3 (NaAu3.17Ga2.33) (VI) in a very different structure with two types of cation sites. Crystal orbital Hamilton population (COHP) analysis obtained from tight-binding electronic structure calculations for idealized I–IV via linear muffin-tin-orbital (LMTO) methods emphasized the major contributions of heteroatomic Au–Ga bonding to the structural stability of these compounds. The relative minima (pseudogaps) in the DOS curves for IV correspond well with the valence electron counts of known representatives of this structure type and, thereby, reveal some magic numbers to guide the search for new isotypic compounds. Theoretical calculation of total energies vs volumes obtained by VASP (Vienna Ab initio Simulation Package) calculations for KAu3Ga2 and RbAu3Ga2 suggest a possible transformation from SrZn5- to BaZn5-types at high pressure.

Smetana, Volodymyr; Miller, Gordon J.; Corbett, John D.

2012-06-27T23:59:59.000Z

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461

Summary - Demonstration Bulk Vitrification System (DBVS) for Low-Actvity Waste at Hanford  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DBVS DBVS ETR Report Date: September 2006 ETR-3 United States Department of Energy Office of Environmental Management (DOE-EM) External Technical Review of the Demonstration Bulk Vitrification System (DBVS) for Low Activity Waste (LAW) at Hanford Why DOE-EM Did This Review The Department of Energy (DOE) is charged with the safe retrieval, treatment and disposal of 53 million gallons of Hanford radioactive waste. The Waste Treatment Plant (WTP) is being designed to treat and vitrify the High Level Waste (HLW) fraction in 20-25 years. The WTP is undersized for vitrifying the LAW fraction over the same time frame. The DOE is evaluating Bulk Vitrification as an alternative to increasing the size of the WTP LAW treatment process. Bulk vitrification is an in-container melting

462

Determination of the 235U enrichment of bulk uranium samples using delayed neutrons.  

SciTech Connect

A technique for utilizing the physics of the delayed neutron re-interrogation method to determine uranium enrichment is presented in this paper. A series of active interrogation measurements was performed using pulsed 14-MeV neutrons and a polyethylene moderated {sup 3}He based neutron detection system. Proof of principle measurements were performed on a set of bulk uranium oxide standards of differing enrichments. A series of measurements was performed on a set of uranium 'unknowns' with and without high-Z gamma-ray shielding (lead) present. Uranium enrichment estimates were obtained for all cases including the bulk uranium samples shielded by lead. Further refinement of this technique is needed to make it a more powerful tool for non-destructive assay of bulk uranium samples.

Myers, W. L. (William L.); Goulding, C. A. (Charles A.); Hollas, C. L. (Charles L.)

2006-01-01T23:59:59.000Z

463

Ultra-soft x-ray absorption spectroscopy: A bulk and surface probe of materials  

SciTech Connect

Direct comparisons between surface and bulk of diverse materials can be made by simultaneous electron yield (5 nm depth sensitivity) and fluorescence yield (200 nm) ultra soft x-ray absorption spectroscopy measurements utilizing a rapid sample interchange apparatus. For example the orientations of functional groups have been characterized at and near the surface of a series of model polymeric materials highlighting the chemical and molecular sensitivity of ultra soft x-ray absorption spectroscopy. In addition we discuss a bulk sensitive use of fluorescence yield to non destructively study a buried metal polymer interface. A second bulk sensitive example is the use of fluorescence yield oxygen K near edge x-ray spectroscopy as a method to determine the hole state density of high Tc materials.

Fischer, D.A. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Mitchell, G.E.; Dekoven, B.M. [Dow Chemical Co., Midland, MI (United States); Yeh, A.T.; Gland, J.L. [Michigan Univ., Ann Arbor, MI (United States); Moodenbaugh, A.R. [Brookhaven National Lab., Upton, NY (United States)

1993-06-01T23:59:59.000Z

464

Ultra-soft x-ray absorption spectroscopy: A bulk and surface probe of materials  

SciTech Connect

Direct comparisons between surface and bulk of diverse materials can be made by simultaneous electron yield (5 nm depth sensitivity) and fluorescence yield (200 nm) ultra soft x-ray absorption spectroscopy measurements utilizing a rapid sample interchange apparatus. For example the orientations of functional groups have been characterized at and near the surface of a series of model polymeric materials highlighting the chemical and molecular sensitivity of ultra soft x-ray absorption spectroscopy. In addition we discuss a bulk sensitive use of fluorescence yield to non destructively study a buried metal polymer interface. A second bulk sensitive example is the use of fluorescence yield oxygen K near edge x-ray spectroscopy as a method to determine the hole state density of high Tc materials.

Fischer, D.A. (National Institute of Standards and Technology, Gaithersburg, MD (United States)); Mitchell, G.E.; Dekoven, B.M. (Dow Chemical Co., Midland, MI (United States)); Yeh, A.T.; Gland, J.L. (Michigan Univ., Ann Arbor, MI (United States)); Moodenbaugh, A.R. (Brookhaven National Lab., Upton, NY (United States))

1993-01-01T23:59:59.000Z

465

Vibration-Induced Conductivity Fluctuation Measurement for Soil Bulk Density Analysis  

E-Print Network (OSTI)

Soil bulk density affects water storage, water and nutrient movement, and plant root activity in the soil profile. Its measurement is difficult in field conditions. Vibration-induced conductivity fluctuation was investigated to quantify soil bulk density with possible field applications in the future. The AC electrical conductivity of soil was measured using a pair of blade-like electrodes while exposing the soil to periodic vibration. The blades were positioned longitudinally and transversally to the direction of the induced vibration to enable the calculation of a normalized index. The normalized index was expected to provide data independent from the vibration strength and to reduce the effect of soil salinity and water content. The experiment was conducted on natural and salinized fine sand at two moisture conditions and four bulk densities. The blade-shaped electrodes improved electrode-soil contact compared to cylindrical electrodes, and thereby, reduced measurement noise. Simulations on a simplified re...

Kishne, Andrea Sz; Chang, Hung-Chih; Kish, Laszlo B

2007-01-01T23:59:59.000Z

466

Form EIA-411, "Coordinated Bulk Power Supply Program Report," | OpenEI  

Open Energy Info (EERE)

411, "Coordinated Bulk Power Supply Program Report," 411, "Coordinated Bulk Power Supply Program Report," Dataset Summary Description The Form EIA-411, "Coordinated Bulk Power Supply Program Report," collects information from the Nation's power system planners about the electricity supply, both capacity and energy, that is needed to serve current demand and for future growth. The reported data can be used to examine such issues as: the reliability of the U.S. electricity system; projections which assess future demand growth and plans for constructing new generating and transmission facilities; and consequences of unavailable or constrained capacity on usage of the existing generation base. Reliability of the electric power system covers three areas: the security of the electrical systems; the usage of

467

Application of Self-Propagating High Temperature Synthesis to the Fabrication of Actinide Bearing Nitride and Other Ceramic Nuclear Fuels  

SciTech Connect

The project uses an exothermic combustion synthesis reaction, termed self-propagating high-temperature synthesis (SHS), to produce high quality, reproducible nitride fuels and other ceramic type nuclear fuels (cercers and cermets, etc.) in conjunction with the fabrication of transmutation fuels. The major research objective of the project is determining the fundamental SHS processing parameters by first using manganese as a surrogate for americium to produce dense Zr-Mn-N ceramic compounds. These fundamental principles will then be transferred to the production of dense Zr-Am-N ceramic materials. A further research objective in the research program is generating fundamental SHS processing data to the synthesis of (i) Pu-Am-Zr-N and (ii) U-Pu-Am-N ceramic fuels. In this case, Ce will be used as the surrogate for Pu, Mn as the surrogate for Am, and depleted uranium as the surrogate for U. Once sufficient fundamental data has been determined for these surrogate systems, the information will be transferred to Idaho National Laboratory (INL) for synthesis of Zr-Am-N, Pu-Am-Zr-N and U-Pu-Am-N ceramic fuels. The high vapor pressures of americium (Am) and americium nitride (AmN) are cause for concern in producing nitride ceramic nuclear fuel that contains Am. Along with the problem of Am retention during the sintering phases of current processing methods, are additional concerns of producing a consistent product of desirable homogeneity, density and porosity. Similar difficulties have been experienced during the laboratory scale process development stage of producing metal alloys containing Am wherein compact powder sintering methods had to be abandoned. Therefore, there is an urgent need to develop a low-temperature or low–heat fuel fabrication process for the synthesis of Am-containing ceramic fuels. Self-propagating high temperature synthesis (SHS), also called combustion synthesis, offers such an alternative process for the synthesis of Am nitride fuels. Although SHS takes thermodynamic advantage of the high combustion temperatures of these exothermic SHS reactions to synthesize the required compounds, the very fast heating, reaction and cooling rates can kinetically generate extremely fast reaction rates and facilitate the retention of volatile species within the rapidly propagating SHS reaction front. The initial objective of the research program is to use Mn as the surrogate for Am to synthesize a reproducible, dense, high quality Zr-Mn-N ceramic compound. Having determined the fundamental SHS reaction parameters and optimized SHS processing steps using Mn as the surrogate for Am, the technology will be transferred to Idaho National Laboratory to successfully synthesize a high quality Zr-Am-N ceramic fuel.

John J. Moore, Marissa M. Reigel, Collin D. Donohoue

2009-04-30T23:59:59.000Z

468

Understanding Bulk Power Reliability: The Importance of Good Data and A Critical Review of Existing Sources  

Science Conference Proceedings (OSTI)

Bulk power system reliability is of critical importance to the electricity sector. Complete and accurate information on events affecting the bulk power system is essential for assessing trends and efforts to maintain or improve reliability. Yet, current sources of this information were not designed with these uses in mind. They were designed, instead, to support real-time emergency notification to industry and government first-responders. This paper reviews information currently collected by both industry and government sources for this purpose and assesses factors that might affect their usefulness in supporting the academic literature that has relied upon them to draw conclusions about the reliability of the US electric power system.

Fisher, Emily; Eto, Joseph H.; LaCommare, Kristina Hamachi

2011-10-19T23:59:59.000Z