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Note: This page contains sample records for the topic "vapor phase epitaxy" from the National Library of EnergyBeta (NLEBeta).
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1

AlGaAsSb/GaSb Distributed Bragg Reflectors Grown by Organometallic Vapor Phase Epitaxy  

SciTech Connect

The first AlGaAsSb/GaSb quarter-wave distributed Bragg reflectors grown by metallic vapor phase epitaxy are reported. The peak reflectance is 96% for a 10-period structure.

C.A. Wang; C.J. Vineis; D.R. Calawa

2002-02-13T23:59:59.000Z

2

Cubic GaN Light Emitting Diode Grown by Metalorganic Vapor-Phase Epitaxy  

E-Print Network (OSTI)

this paper, we report on the doping characteristics of Si and Mg in the growth of cubic GaN by metalorganic vapor-phase epitaxy (MOVPE). We also report the growth of a p-n diode structure made of cubic GaN, and its characterization by electron-beam-induced-current (EBIC) and current injection measurements.

Hidenao Tanaka Member; Vapor-phase Epitaxy; Atsushi Nakadaira

2000-01-01T23:59:59.000Z

3

Growth of vertical-cavity surface emitting lasers by metalorganic vapor phase epitaxy  

SciTech Connect

We present growth and characterization of visible and near-infrared vertical-cavity surface emitting lasers (VCSELs) grown by metalorganic vapor phase epitaxy. Discussions on the growth issue of VCSEL materials include growth rate and composition control using an {ital in}{ital situ} normal-incidence reflectometer, comprehensive p- and n-type doping study in AlGaAs by CCl{sub 4} and Si{sub 2}H{sub 6} over the entire composition range, and optimization of ultra-high material uniformity. We also demonstrate our recent achievements of all-AlGaAs VCSELs which include the first room-temperature continuous- wave demonstration of 700-nm red VCSELs and high-efficiency and low- threshold voltage 850-nm VCSELs.

Hou, H.Q.; Hammons, B.E.; Crawford, M.H.; Lear, K.L.; Choquette, K.D.

1996-10-01T23:59:59.000Z

4

Journal of Light Emitting Diodes Vol 2 N0 1, April 2010 1 Abstract--In metal organic vapor phase epitaxy we developed  

E-Print Network (OSTI)

Journal of Light Emitting Diodes Vol 2 N0 1, April 2010 1 Abstract-- In metal organic vapor phase epitaxy we developed GaInN/GaN quantum well material suitable for 500 ­ 580 nm light emitting diodes at longer wavelengths. Index Terms-- a-plane GaN, GaInN, Green light emitting diode, m-plane GaN I

Wetzel, Christian M.

5

Growth and characterization of In{sub 0.2}Ga{sub 0.8}Sb device structures using metalorganic vapor phase epitaxy  

DOE Green Energy (OSTI)

In{sub 0.2}Ga{sub 0.8}Sb epitaxial layers and thermophotovoltaic (TPV) device structures have been grown on GaSb and GaAs substrates by metalorganic vapor phase epitaxy (MOVPE). Control of the n-type doping up to 1 {times} 10{sup 18} cm{sup {minus}3} was achieved using diethyltellurium (DETE) as the dopant source. A Hall mobility of greater than 8,000 cm{sup 2}/Vs at 77 K was obtained for a 3 {times} 10{sup 17} cm{sup {minus}3} doped In{sub 0.2}Ga{sub 0.8}Sb layer grown on high-resistivity GaSb substrate. The In{sub 0.2}Ga{sub 0.8}Sb epilayers directly grown on GaSb substrates were tilted with respect to the substrates, with the amount of tilt increasing with the layer thickness. Transmission electron microscopy (TEM) studies of the layers showed the presence of dislocation networks across the epilayers parallel to the interface at different distances from the interface, but the layers above this dislocation network were virtually free of dislocations. A strong correlation between epilayer tilt and TPV device properties was found, with layers having more tilt providing better devices. The results suggest that the dislocations moving parallel to the interface cause lattice tilt, and control of this layer tilt may enable the fabrication of better quality device structures.

Ehsani, H.; Bhat, I.; Hitchcock, C.; Gutmann, R. [Rensselaer Polytechnic Inst., Troy, NY (United States); Charache, G.; Freeman, M. [Lockheed Martin Inc., Schenectady, NY (United States)

1997-05-01T23:59:59.000Z

6

METAL ORGANIC VAPOR PHASE EPITAXY  

Science Conference Proceedings (OSTI)

Jun 4, 2004 ... used to texture the surface of a Light Emitting Diode (LED) structure, enhancing light extraction by a factor of 2 to 3 times. This paper will.

7

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

8

Vapor phase modifiers for oxidative coupling  

DOE Patents (OSTI)

Volatilized metal compounds retard vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, Barbara K. (Charleston, WV)

1991-01-01T23:59:59.000Z

9

Organometallic Vapor Phase Epitaxy Technical Program  

Science Conference Proceedings (OSTI)

Mar 12, 2001 ... integrity, Emergency Response, Safety for the ESG products. The pre- ... systems, multi-point gas monitoring, and one or more emergency gas.

10

Vapor phase heat transport systems  

DOE Green Energy (OSTI)

Vapor phase heat-transport systems are being tested in two of the passive test cells at Los Alamos. The systems consist of an active fin-and-tube solar collector and a condenser inside a water storage tank. The refrigerant, R-11, can be returned to the collector by a pump or by a self-pumping scheme. In one of the test cells the liquid was self-pumped to the roof-mounted collector 17 ft above the condenser. A mechanical valve was designed and tested that showed that the system could operate in a completely passive mode. Performance comparisons have been made with a passive water wall test cell.

Hedstrom, J.C.

1984-01-01T23:59:59.000Z

11

Vapor phase modifiers for oxidative coupling  

DOE Patents (OSTI)

Volatilized metal compounds are described which are capable of retarding vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, B.K.

1991-12-17T23:59:59.000Z

12

Chemical Vapor Deposition of Silicon Carbide Epitaxial Films and their Characterization  

DOE Green Energy (OSTI)

A chemical vapor deposition (CVD) system was designed and fabricated in our laboratory and SiC homo-epitaxial layers were grown in the CVD process using silicon tetrachloride and propane precursors with hydrogen as a carrier gas. The temperature field was generated using numerical modeling. Gas flow rates, temperature field, and the gradients are found to influence the growth rates of the epitaxial layers. Growth rates were found to increase as the temperature increased at high carrier gas flow rate, while at lower carrier gas flow rate, growth rates were observed to decrease as the temperature increased. Based on the equilibrium model, 'thermodynamically controlled growth' accounts for the growth rate reduction. The grown epitaxial layers were characterized using various techniques. Reduction in the threading screw dislocation (SD) density in the epilayers was observed. Suitable models were developed for explaining the reduction in the SD density as well as the conversion of basal plane dislocations (BPDs) into threading edge dislocations (TEDs).

Dhanaraj,G.; Chen, Y.; Dudley, M.; Cai, D.; Zhang, H.

2007-01-01T23:59:59.000Z

13

Growth of homo-epitaxial silicon at low temperatures using hot wire chemical vapor deposition  

DOE Green Energy (OSTI)

The authors report on the first known growth of high-quality epitaxial Si via the hot wire chemical vapor deposition (HWCVD) method. This method yields device-quality epitaxial Si at the comparatively low temperatures of 195 to 450 C, and relatively high growth rates of 3 to 20 {angstrom}/sec. Layers up to 4,500-{angstrom} thick have been grown. These epitaxial layers have been characterized by transmission electron microscopy (TEM), indicating large regions of nearly perfect atomic registration. Electron channeling patterns (ECPs) generated on a scanning electron microscope (SEM) have been used to characterize as well as optimize the growth process. Electron beam induced current (EBIC) characterization has also been performed, indicating defect densities as low as 5 x 104/cm{sup 2}. Secondary ion beam mass spectrometry (SIMS) data shows that these layers have reasonable impurity levels within the constraints of the current deposition system. Both n and p-type layers were grown, and p/n diodes have been fabricated.

Thiesen, J.; Jones, K.M.; Matson, R.; Reedy, R.; Crandall, R.; Iwaniczko, E.; Mahan, H.

1999-12-13T23:59:59.000Z

14

Liquid-phase compositions from vapor-phase analyses  

SciTech Connect

Arsenic normally is not considered to be a contaminant. However, because arsenic was found in many cylinders of UF{sub 6}, including in corrosion products, a study was performed of the distribution of the two arsenic fluorides, AsF{sub 3} and AsF{sub 5}, between liquid and vapor phases. The results of the study pertain to condensation or vaporization of liquid UF{sub 6}. This study includes use of various experimental data plus many extrapolations necessitated by the meagerness of the experimental data. The results of this study provide additional support for the vapor-liquid equilibrium model of J.M. Prausnitz and his coworkers as a means of describing the distribution of various impurities between vapor and liquid phases of UF{sub 6}. Thus, it is concluded that AsF{sub 3} will tend to concentrate in the liquid phase but that the concentration of AsF{sub 5} in the vapor phase will exceed its liquid-phase concentration by a factor of about 7.5, which is in agreement with experimental data. Because the weight of the liquid phase in a condensation operation may be in the range of thousands of times that of the vapor phase, most of any AsF{sub 5} will be in the liquid phase in spite of this separation factor of 7.5. It may also be concluded that any arsenic fluorides fed into a uranium isotope separation plant will either travel with other low-molecular-weight gases or react with materials present in the plant. 25 refs., 3 figs., 6 tabs.

Davis, W. Jr. (Oak Ridge Gaseous Diffusion Plant, TN (USA)); Cochran, H.D. (Oak Ridge National Lab., TN (USA))

1990-02-01T23:59:59.000Z

15

Tenth Biennial Workshop on Organometallic Vapor Phase Epitaxy  

Science Conference Proceedings (OSTI)

Mar 15, 2001 ... National Renewable Energy Lab. Dr. Simon Watkins. Simon Fraser ..... Payment shall be made in US dollars drawn on a US bank. r Credit Card ...

16

Metal Organic Vapor Phase Epitaxy ICMOVPE-XV  

Science Conference Proceedings (OSTI)

Growth of Energy Technology (solid state lighting, PV, Thermoelectrics, etc) ..... treatment prices when booked in advance for the attendees and guests of.

17

High temperature step-flow growth of gallium phosphide by molecular beam epitaxy and metalorganic chemical vapor deposition  

Science Conference Proceedings (OSTI)

Post-growth surface morphologies of high-temperature homoepitaxial GaP films grown by molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) have been studied. Smooth, stepped surface morphologies of MBE-grown layers, measured by atomic force microscopy, were found for a wide range of substrate temperatures and P{sub 2}:Ga flux ratios. A MOCVD-based growth study performed under similar conditions to MBE-grown samples shows a nearly identical smooth, step-flow surface morphology, presenting a convergence of growth conditions for the two different methods. The additional understanding of GaP epitaxy gained from this study will impact its use in applications that include GaP-based device technologies, III-V metamorphic buffers, and III-V materials integration with silicon.

Ratcliff, C. [Department of Electrical and Computer Engineering, Ohio State University, Columbus, Ohio 43210 (United States); Grassman, T. J.; Ringel, S. A. [Department of Electrical and Computer Engineering, Ohio State University, Columbus, Ohio 43210 (United States); Institute for Materials Research, Ohio State University, Columbus, Ohio 43210 (United States); Carlin, J. A. [Institute for Materials Research, Ohio State University, Columbus, Ohio 43210 (United States)

2011-10-03T23:59:59.000Z

18

Preliminary assessment of halogenated alkanes as vapor-phase tracers  

DOE Green Energy (OSTI)

New tracers are needed to evaluate the efficiency of injection strategies in vapor-dominated environments. One group of compounds that seems to meet the requirements for vapor-phase tracing are the halogenated alkanes (HCFCs). HCFCs are generally nontoxic, and extrapolation of tabulated thermodynamic data indicate that they will be thermally stable and nonreactive in a geothermal environment. The solubilities and stabilities of these compounds, which form several homologous series, vary according to the substituent ratios of fluorine, chlorine, and hydrogen. Laboratory and field tests that will further define the suitability of HCFCs as vapor-phase tracers are under way.

Adams, Michael C.; Moore, Joseph N.; Hirtz, Paul

1991-01-01T23:59:59.000Z

19

Ultrahigh growth rate of epitaxial silicon by chemical vapor deposition at low temperature with neopentasilane  

E-Print Network (OSTI)

- iane SiH4 to disilane Si2H6 , to trisilane, Si3H8 2 leads to increased epitaxy growth rates at the same growth rate was 0.6 nm/min, and the disilane growth rate was 8 nm/min. In this work, we explored the use

20

Structure/processing relationships in vapor-liquid-solid nanowire epitaxy  

E-Print Network (OSTI)

The synthesis of Si and III-V nanowires using the vapor-liquid-solid (VLS) growth mechanism and low-cost Si substrates was investigated. The VLS mechanism allows fabrication of heterostructures which are not readily ...

Boles, Steven Tyler

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Separation of heavy water by vapor-phase thermal diffusion coupled with distillation and condensation  

Science Conference Proceedings (OSTI)

A study on the enrichment of heavy water in a vapor-phase thermal-diffusion column has been conducted. With the combination of the effects of distillation, vapor-phase thermal diffusion, and partial condensation, considerable improvement in the degree of enrichment has been achieved in a vapor-phase column rather than in a liquid-phase column. It was also found that even the part of enrichment contributed only by vapor-phase thermal-diffusion effect is much higher than that obtained by liquid-phase thermal diffusion.

Yeh, H.M. [Tamkang Univ., Taiwan (China); Chang, S.M. [Cheng Kung Univ., Taiwan (China)

1994-08-01T23:59:59.000Z

22

Solid-phase epitaxy of silicon amorphized by implantation of the alkali elements rubidium and cesium  

Science Conference Proceedings (OSTI)

The redistribution of implanted Rb and Cs profiles in amorphous silicon during solid-phase epitaxial recrystallization has been investigated by Rutherford backscattering spectroscopy and secondary ion mass spectroscopy. For the implantation dose used in these experiments, the alkali atoms segregate at the a-Si/c-Si interface during annealing resulting in concentration peaks near the interface. In this way, the alkali atoms are moved towards the surface. Rutherford backscattering spectroscopy in ion channeling configuration was performed to measure average recrystallization rates of the amorphous silicon layers. Preliminary studies on the influence of the alkali atoms on the solid-phase epitaxial regrowth rate reveal a strong retardation compared to the intrinsic recrystallization rate.

Maier, R.; Haeublein, V.; Ryssel, H.; Voellm, H.; Feili, D.; Seidel, H.; Frey, L. [Lehrstuhl fuer Elektronische Bauelemente (LEB), Universitaet Erlangen-Nuernberg, Cauerstrasse 6, 91058 Erlangen (Germany); Fraunhofer-Institut fuer Integrierte Systeme und Bauelementetechnologie (IISB), Schottkystrasse 10, 91058 Erlangen (Germany); Lehrstuhl fuer Elektronische Bauelemente (LEB), Universitaet Erlangen-Nuernberg, Cauerstrasse 6, 91058 Erlangen (Germany) and Fraunhofer-Institut fuer Integrierte Systeme und Bauelementetechnologie (IISB), Schottkystrasse 10, 9 (Germany); Lehrstuhl fuer Mikromechanik, Mikrofluidik/ Mikroaktorik (LMM), Universitaet des Saarlandes, Campus A5.1, 66123 Saarbruecken (Germany); Lehrstuhl fuer Elektronische Bauelemente (LEB), Universitaet Erlangen-Nuernberg, Cauerstrasse 6, 91058 Erlangen (Germany) and Fraunhofer-Institut fuer Integrierte Systeme und Bauelementetechnologie (IISB), Schottkystrasse 10,91 (Germany)

2012-11-06T23:59:59.000Z

23

The use of electron channeling patterns for process optimization of low-temperature epitaxial silicon using hot-wire chemical vapor deposition  

DOE Green Energy (OSTI)

The authors demonstrate the first reported use of electron channeling patterns (ECPs) as a response for a statistical design of experiments process-optimization for epitaxial silicon. In an effort to fully characterize the new hot-wire chemical vapor deposition (HWCVD) method of epitaxial growth recently discovered at NREL, a large number of parameters with widely varying values needed to be considered. To accomplish this, they used the statistical design of experiments method. This technique allows one to limit the number of sample points necessary to evaluate a given parameter space. In this work they demonstrate how ECPs can effectively be used to optimize the process space as well as to quickly and economically provide the process engineer with absolutely key information.

Matson, R.; Thiesen, J.; Jones, K.M.; Crandall, R.; Iwaniczko, E.; Mahan, H.

1999-10-25T23:59:59.000Z

24

Vaporization behavior of non-stoichiometric refractory carbide materials and direct observations of the vapor phase using laser diagnostics  

DOE Green Energy (OSTI)

Transition metal and actinide carbides, such as ZrC or NbC and UC or ThC, exhibit a wide range of stoichiometry, and therefore vaporize incongruently. At long times, steady state vaporization can be achieved where relative concentrations of atomic species on solid surface equals that in the gas phase. The surface composition under these steady state conditions is termed the congruently vaporizing composition, (CVC). Modeling the vaporization or corrosion behavior of this dynamic process is complex and requires an understanding of how the surface composition changes with time and a knowledge of CVC, which is both temperature and atmosphere dependent. This paper describes vaporization and corrosion behavior of non-stoichiometric refractory carbide materials and, as an example, describes a thermokinetic model that characterizes the vaporization behavior of the complex carbide U{sub x}Zr{sub 1-x}C{sub y} in hydrogen at 2500 to 3200 K. This model demonstrates that steady state corrosion of U{sub x}Zr{sub l-x}C{sub y} is rate limited by gaseous transport of Zr where partial pressure of Zr is determined by CVC. This paper also briefly describes efforts to image and characterize the vapor phase above the surface of ZrC in static and flowing gas environments using planar laser induced fluorescence. We have developed the method for monitoring and controlling the corrosion behavior of nuclear fuels in nuclear thermal rockets. However, the techniques described can be used, to image boundary layers, and could be used verifying corrosion models.

Butt, D.P.; Wantuck, P.J.; Rehse, S.J.; Wallace, T.C. Sr.

1993-09-01T23:59:59.000Z

25

Rapid liquid phase epitaxial growth studies of GaAs: Final report, July 1984-June 1987  

Science Conference Proceedings (OSTI)

Single crystal layers of gallium arsenide have been grown on (111) and (100) oriented GaAs substrates from a flowing, GaAs saturated, gallium solution with a few degrees temperature differential across the liquid/solid interface. Very high growth rates, on the order of 8..mu..m per minute, have been observed. Such rates are in agreement with the growth theory developed as part of this program, and are about two orders greater than those typically achieved in conventional, static solution, liquid phase epitaxy. Both undoped and p-doped (Si) GaAs layers have been grown and some of their material properties measured. Good crystallinity was inferred from the narrowness of x-ray diffraction lines and from the intensities of the photoluminescence responses of all specimens sampled. While these results do not prove that the epi material is of photovoltaic quality, they indicate both a high crystallographic perfection and a low density of life-time poisoning impurities; conditions which are usually necessary for PV device development. Thus far, smooth surfaces have not been produced directly by the rapid liquid phase epitaxy (RLPE) process. The rough surface morphologies are due, at least in part, to incomplete wipe off of the liquid when the substrate is withdrawn at the end of the growth cycle. Another potential source is growth instabilities which will be discussed later. This report summarizes the three year research program of the RLPE process sponsored by DOE-SOLERAS.

Gerritsen, H.J.; Crisman, E.E.

1987-01-01T23:59:59.000Z

26

Epitaxial Thin Film Silicon Solar Cells Fabricated by Hot Wire Chemical Vapor Deposition Below 750 ..deg..C: Preprint  

Science Conference Proceedings (OSTI)

We report on fabricating film c-Si solar cells on Si wafer templates by hot-wire chemical vapor deposition. These devices, grown at glass-compatible temperatures 500 mV and efficiencies > 5%.

Alberi, K.; Martin, I. T.; Shub, M.; Teplin, C. W.; Iwaniczko, E.; Xu, Y.; duda, A.; Stradin, P.; Johnston, S. W.; Romero, M. J.; Branz, H. M.; Young, D. L.

2009-06-01T23:59:59.000Z

27

Microwave-assisted fast vapor-phase transport synthesis of MnAPO-5 molecular sieves  

Science Conference Proceedings (OSTI)

MnAPO-5 was prepared by a microwave-assisted vapor-phase transport method at 180 deg. C in short times. The products were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectra, UV-vis spectroscopic measurement, NH{sub 3}-temperature-programmed desorption and esterification reaction. It was found that dry gels prepared with aluminum isopropoxide, phosphoric acid and manganese acetate could be transferred to MnAPO-5 in the vapors of triethylamine and water by the microwave-assisted vapor-phase transport method at 180 deg. C for less than 30 min. The crystallization time was greatly reduced by the microwave heating compared with the conventional heating. The resulting MnAPO-5 exhibited much smaller particle sizes, higher surface areas and slightly higher catalytic activity in the esterification of acetic acid and butyl alcohol than those prepared by the conventional vapor-phase transport method and hydrothermal synthesis.

Shao Hui [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); Department of Chemical Engineering, Jiangsu Polytechnic University, Changzhou 213016 (China); Yao Jianfeng; Ke Xuebin [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); Zhang Lixiong [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China)], E-mail: lixiongzhang@yahoo.com; Xu Nanping [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China)

2009-04-02T23:59:59.000Z

28

Epitaxial Thin Film Silicon Solar Cells Fabricated by Hot Wire Chemical Vapor Deposition Below 750 ..deg..C: Preprint  

SciTech Connect

We report on fabricating film c-Si solar cells on Si wafer templates by hot-wire chemical vapor deposition. These devices, grown at glass-compatible temperatures < 750..deg..C, demonstrate open-circuit voltages > 500 mV and efficiencies > 5%.

Alberi, K.; Martin, I. T.; Shub, M.; Teplin, C. W.; Iwaniczko, E.; Xu, Y.; duda, A.; Stradin, P.; Johnston, S. W.; Romero, M. J.; Branz, H. M.; Young, D. L.

2009-06-01T23:59:59.000Z

29

Metalorganic Vapor-Phase Epitaxial Growth and Characterization of Quaternary AlGaInN  

SciTech Connect

In this letter we report the growth (by MOVPE) and characterization of quaternary AlGaInN. A combination of PL, high-resolution XRD, and RBS characterizations enables us to explore and delineate the contours of equil-emission energy and lattice parameters as functions of the quaternary compositions. The observation of room temperature PL emission as short as 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN (and possibly GaN). AlGaInN/GdnN MQW heterostructures have also been grown; both x-ray diffraction and PL measurement suggest the possibility of incorporating this quaternary into optoelectronic devices.

BANAS, MICHAEL ANTHONY; CRAWFORD, MARY H.; FIGIEL, JEFFREY J.; HAN, JUNG; LEE, STEPHEN R.; MYERS JR., SAMUEL M.; PETERSON, GARY D.

1999-09-27T23:59:59.000Z

30

Photoconduction efficiencies and dynamics in GaN nanowires grown by chemical vapor deposition and molecular beam epitaxy: A comparison study  

Science Conference Proceedings (OSTI)

The normalized gains, which determines the intrinsic photoconduction (PC) efficiencies, have been defined and compared for the gallium nitride (GaN) nanowires (NWs) grown by chemical vapor deposition (CVD) and molecular beam epitaxy (MBE). By excluding the contributions of experimental parameters and under the same light intensity, the CVD-grown GaN NWs exhibit the normalized gain which is near two orders of magnitude higher than that of the MBE-ones. The temperature-dependent time-resolved photocurrent measurement further indicates that the higher photoconduction efficiency in the CVD-GaN NWs is originated from the longer carrier lifetime induced by the higher barrier height ({phi}{sub B} = 160 {+-} 30 mV) of surface band bending. In addition, the experimentally estimated barrier height at 20 {+-} 2 mV for the MBE-GaN NWs, which is much lower than the theoretical value, is inferred to be resulted from the lower density of charged surface states on the non-polar side walls.

Chen, R. S. [Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Tsai, H. Y. [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Huang, Y. S. [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Chen, Y. T. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China); Chen, L. C. [Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China); Chen, K. H. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China); Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China)

2012-09-10T23:59:59.000Z

31

Liquid-phase dispersion during injection into vapor-dominated reservoirs  

DOE Green Energy (OSTI)

The behavior of water injection plumes in vapor-dominated reservoirs is examined. Stressing the similarity to water infiltration in heterogeneous soils, we suggest that ever-present heterogeneities in individual fractures and fracture networks will cause a lateral broadening of descending injection plumes. The process of lateral spreading of liquid phase is viewed in analogy to transverse dispersion in miscible displacement. To account for the postulated ``phase dispersion`` the conventional two-phase immiscible flow theory is extended by adding a Fickian-type dispersive term. The validity of the proposed phase dispersion model is explored by means of simulations with detailed resolution of small-scale heterogeneity. We also present an illustrative application to injection into a depleted vapor zone. It is concluded that phase dispersion effects will broaden descending injection plumes, with important consequences for pressure support and potential water breakthrough at neighboring production wells.

Pruess, K.

1994-01-01T23:59:59.000Z

32

Condensed phase conversion and growth of nanorods and other materials instead of from vapor  

DOE Patents (OSTI)

Compositions, systems and methods are described for condensed phase conversion and growth of nanorods and other materials. A method includes providing a condensed phase matrix material; and activating the condensed phase matrix material to produce a plurality of nanorods by condensed phase conversion and growth from the condensed phase matrix material instead of from vapor. The compositions are very strong. The compositions and methods provide advantages because they allow (1) formation rates of nanostructures necessary for reasonable production rates, and (2) the near net shaped production of component structures.

Geohegan, David B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Puretzky, Alex A. (Knoxville, TN); Fan, Xudong (Oak Ridge, TN)

2010-10-19T23:59:59.000Z

33

Published on Web 08/16/2003 Vapor Phase Synthesis of Tungsten Nanowires  

E-Print Network (OSTI)

Vapor phase methods for synthesizing metal nanowires directly without the help of templates have not been studied extensively. Even though there have been few reports with one dating back to 1877 on metal whisker synthesis from the vapor phase, the inconclusive growth mechanism did not lead to any serious developments for nanowires. 1 Recently, there are also two reports with one using hydrogen on tungsten oxide for tungsten nanowires, and another using decomposition of tungsten complexed organic precursors for amorphous carbon sheathed, polycrystalline tungsten nanowires. 2 In this context, we report a novel method in which nucleation and growth of metal oxides at temperatures higher than the oxide decomposition temperatures lead to the respective metal nanowires. Specifically, we demonstrate this concept with the bulk synthesis of tungsten nanowires. The chemical vapor transport of tungsten in the presence of oxygen onto substrates kept at temperatures

Sreeram Vaddiraju; Hari Ch; Mahendra K. Sunkara

2003-01-01T23:59:59.000Z

34

Microsoft Word - Vapor Phase Elemental Sulfur Tech Brief DRAFT bbl 08-24.docx  

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

AT A GLANCE AT A GLANCE ï‚· eliminates excavation expense ï‚· applicable to large or small sites ï‚· straightforward deployment ï‚· uses heat to distribute sulfur throughout a soil ï‚· mercury reacts with sulfur to form immobile and insoluble minerals ï‚· patent applied for TechBrief Vapor Phase Elemental Sulfur Amendment for Sequestering Mercury in Contaminated Soil Scientists at the Savannah River National Laboratory (SRNL) have identified a method of targeting mercury in contaminated soil zone by use of sulfur vapor heated gas. Background Mercury contamination in soil is a common problem in the environment. The most common treatment is excavation - a method that works well for small sites where the

35

Liquid-phase and vapor-phase dehydration of organic/water solutions  

DOE Patents (OSTI)

Processes for dehydrating an organic/water solution by pervaporation or vapor separation using fluorinated membranes. The processes are particularly useful for treating mixtures containing light organic components, such as ethanol, isopropanol or acetic acid.

Huang, Yu (Palo Alto, CA); Ly, Jennifer (San Jose, CA); Aldajani, Tiem (San Jose, CA); Baker, Richard W. (Palo Alto, CA)

2011-08-23T23:59:59.000Z

36

Reducing dislocations in semiconductors utilizing repeated thermal cycling during multistage epitaxial growth  

DOE Patents (OSTI)

Dislocation densities are reduced in growing semiconductors from the vapor phase by employing a technique of interrupting growth, cooling the layer so far deposited, and then repeating the process until a high quality active top layer is achieved. The method of interrupted growth, coupled with thermal cycling, permits dislocations to be trapped in the initial stages of epitaxial growth.

Fan, John C. C. (Chestnut Hill, MA); Tsaur, Bor-Yeu (Arlington, MA); Gale, Ronald P. (Bedford, MA); Davis, Frances M. (Framingham, MA)

1992-02-25T23:59:59.000Z

37

Reducing dislocations in semiconductors utilizing repeated thermal cycling during multistage epitaxial growth  

DOE Patents (OSTI)

Dislocation densities are reduced in growing semiconductors from the vapor phase by employing a technique of interrupting growth, cooling the layer so far deposited, and then repeating the process until a high quality active top layer is achieved. The method of interrupted growth, coupled with thermal cycling, permits dislocations to be trapped in the initial stages of epitaxial growth.

Fan, John C. C. (Chestnut Hill, MA); Tsaur, Bor-Yeu (Arlington, MA); Gale, Ronald P. (Bedford, MA); Davis, Frances M. (Framingham, MA)

1986-12-30T23:59:59.000Z

38

Compound nuclear decay and the liquid to vapor phase transition: a physical picture  

E-Print Network (OSTI)

Analyses of multifragmentation in terms of the Fisher droplet model (FDM) and the associated construction of a nuclear phase diagram bring forth the problem of the actual existence of the nuclear vapor phase and the meaning of its associated pressure. We present here a physical picture of fragment production from excited nuclei that solves this problem and establishes the relationship between the FDM and the standard compound nucleus decay rate for rare particles emitted in first-chance decay. The compound thermal emission picture is formally equivalent to a FDM-like equilibrium description and avoids the problem of the vapor while also explaining the observation of Boltzmann-like distribution of emission times. In this picture a simple Fermi gas thermometric relation is naturally justified and verified in the fragment yields and time scales. Low energy compound nucleus fragment yields scale according to the FDM and lead to an estimate of the infinite symmetric nuclear matter critical temperature between 18 a...

Moretto, L G; Phair, L

2005-01-01T23:59:59.000Z

39

Inhibition of Pitting and Crevice Corrosion by Filming Amines and Vapor Phase Corrosion Inhibitors  

Science Conference Proceedings (OSTI)

The increase of fossil units that are being removed from service for indeterminate periods due to economic dispatch, seasonal conditions of excess generating capacity, or temporary decommissioning of generating assets necessitates alternative protective measures to prevent and reduce deterioration of the system components during these periods of idle operation. Preservation methods and techniques using vapor phase corrosion inhibitors and film-forming hydrophobic amines may provide an effective alternati...

2012-01-17T23:59:59.000Z

40

Metal organic chemical vapor deposition of 111-v compounds on silicon  

DOE Patents (OSTI)

Expitaxial composite comprising thin films of a Group III-V compound semiconductor such as gallium arsenide (GaAs) or gallium aluminum arsenide (GaAlAs) on single crystal silicon substrates are disclosed. Also disclosed is a process for manufacturing, by chemical deposition from the vapor phase, epitaxial composites as above described, and to semiconductor devices based on such epitaxial composites. The composites have particular utility for use in making light sensitive solid state solar cells.

Vernon, Stanley M. (Wellesley, MA)

1986-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Rapid, controllable growth of epitaxial silicon films - Energy ...  

Many of the current industry cells in ... A method of producing epitaxial silicon films on a c-Si wafer substrate using hot wire chemical vapor ...

42

Calculation of two-phase dispersed droplet-in-vapor flows including normal shock waves  

DOE Green Energy (OSTI)

A method for calculating quasi-one-dimensional, steady-state, two-phase dispersed droplet-in-vapor flow has been developed. The technique is applicable to both subsonic and supersonic single component flow in which normal shock waves may occur, and is the basis for a two-dimensional model. The flow is assumed to be inviscid except for droplet drag. Temperature and pressure equilibrium between phases is assumed, although this is not a requirement of the technique. Example calculations of flow in one-dimensional nozzles with and without normal shocks are given and compared with experimentally measured pressure profiles for both low quality and high quality two-phase steam/water flow.

Comfort, W.J.; Alger, T.W.; Giedt, W.H.; Crowe, C.T.

1976-07-28T23:59:59.000Z

43

Compound nuclear decay and the liquid to vapor phase transition: a physical picture  

E-Print Network (OSTI)

Analyses of multifragmentation in terms of the Fisher droplet model (FDM) and the associated construction of a nuclear phase diagram bring forth the problem of the actual existence of the nuclear vapor phase and the meaning of its associated pressure. We present here a physical picture of fragment production from excited nuclei that solves this problem and establishes the relationship between the FDM and the standard compound nucleus decay rate for rare particles emitted in first-chance decay. The compound thermal emission picture is formally equivalent to a FDM-like equilibrium description and avoids the problem of the vapor while also explaining the observation of Boltzmann-like distribution of emission times. In this picture a simple Fermi gas thermometric relation is naturally justified and verified in the fragment yields and time scales. Low energy compound nucleus fragment yields scale according to the FDM and lead to an estimate of the infinite symmetric nuclear matter critical temperature between 18 and 27 MeV depending on the choice of the surface energy coefficient of nuclear matter.

L. G. Moretto; J. B. Elliott; L. Phair

2005-07-08T23:59:59.000Z

44

Epitaxial Stabilization of a Morphotropic Phase Boundary in Lead-Free Ferroelectric Thin Films  

E-Print Network (OSTI)

energy barrier for phase transformation in these films. The piezoelectric andpiezoelectric charge coefficient direct current density functional theory dysprosium scandate electric field coercive field energyenergy surface” near a structural phase boundary is the origin of the enhanced piezoelectric

Zeches, Robert James

2011-01-01T23:59:59.000Z

45

Gas-phase reaction study of disilane pyrolysis: Applications to low pressure chemical vapor deposition  

SciTech Connect

The gas-phase thermal reactions during disilane decomposition at low pressure chemical vapor deposition conditions were studied from 300 to 1,000 K using resonance enhanced multiphoton ionization (REMPI) and multiphoton ionization (MPI). REMPI of gas-phase Si, mass 28, was detected from 640 to 840 K and 1 to 10 Torr, with a maximum signal intensity between 700 to 720 K. During disilane decomposition, no SiH (427.8 nm), SiH[sub 2] (494-515 nm), or SiH[sub 3] (419.0 nm) was detected. MPI of higher silanes, silenes, and silylenes were detected through mass fragments 2, 32, and 60; these species reached a maximum signal intensity 20 degrees prior to the mass-28 maximum. Modeling studies that included a detailed low pressure gas-phase kinetic scheme predict relative gas-phase partial pressures generated during disilane pyrolysis. The model predicted experimental trends in the Si partial pressure and the higher silane, silene, and silylene partial pressures.

Johannes, J.E.; Ekerdt, J.G. (Univ. of Texas, Austin, TX (United States). Dept. of Chemical Engineering)

1994-08-01T23:59:59.000Z

46

Tank vapor sampling and analysis data package for tank 241-C-106 waste retrieval sluicing system process test phase III  

Science Conference Proceedings (OSTI)

This data package presents sampling data and analytical results from the March 28, 1999, vapor sampling of Hanford Site single-shell tank 241-C-106 during active sluicing. Samples were obtained from the 296-C-006 ventilation system stack and ambient air at several locations. Characterization Project Operations (CPO) was responsible for the collection of all SUMMATM canister samples. The Special Analytical Support (SAS) vapor team was responsible for the collection of all triple sorbent trap (TST), sorbent tube train (STT), polyurethane foam (PUF), and particulate filter samples collected at the 296-C-006 stack. The SAS vapor team used the non-electrical vapor sampling (NEVS) system to collect samples of the air, gases, and vapors from the 296-C-006 stack. The SAS vapor team collected and analyzed these samples for Lockheed Martin Hanford Corporation (LMHC) and Tank Waste Remediation System (TWRS) in accordance with the sampling and analytical requirements specified in the Waste Retrieval Sluicing System Vapor Sampling and Analysis Plan (SAP) for Evaluation of Organic Emissions, Process Test Phase III, HNF-4212, Rev. 0-A, (LMHC, 1999). All samples were stored in a secured Radioactive Materials Area (RMA) until the samples were radiologically released and received by SAS for analysis. The Waste Sampling and Characterization Facility (WSCF) performed the radiological analyses. The samples were received on April 5, 1999.

LOCKREM, L.L.

1999-08-13T23:59:59.000Z

47

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

DOE Green Energy (OSTI)

This report summarizes work of this project from October 2003 through March 2004. The major focus of the research was to further investigate BTEX removal from produced water, to quantify metal ion removal from produced water, and to evaluate a lab-scale vapor phase bioreactor (VPB) for BTEX destruction in off-gases produced during SMZ regeneration. Batch equilibrium sorption studies were conducted to evaluate the effect of semi-volatile organic compounds commonly found in produced water on the sorption of benzene, toluene, ethylbenzene, and xylene (BTEX) onto surfactant-modified zeolite (SMZ) and to examine selected metal ion sorption onto SMZ. The sorption of polar semi-volatile organic compounds and metals commonly found in produced water onto SMZ was also investigated. Batch experiments were performed in a synthetic saline solution that mimicked water from a produced water collection facility in Wyoming. Results indicated that increasing concentrations of semi-volatile organic compounds increased BTEX sorption. The sorption of phenol compounds could be described by linear isotherms, but the linear partitioning coefficients decreased with increasing pH, especially above the pKa's of the compounds. Linear correlations relating partitioning coefficients of phenol compounds with their respective solubilities and octanol-water partitioning coefficients were developed for data collected at pH 7.2. The sorption of chromate, selenate, and barium in synthetic produced water were also described by Langmuir isotherms. Experiments conducted with a lab-scale vapor phase bioreactor (VPB) packed with foam indicated that this system could achieve high BTEX removal efficiencies once the nutrient delivery system was optimized. The xylene isomers and benzene were found to require the greatest biofilter bed depth for removal. This result suggested that these VOCs would ultimately control the size of the biofilter required for the produced water application. The biofilter recovered rapidly from shutdowns showing that the system was resilient to discontinuous feed conditions therefore provided flexibility on the SMZ regeneration process.

Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

2004-03-11T23:59:59.000Z

48

Method for the generation of variable density metal vapors which bypasses the liquidus phase  

DOE Patents (OSTI)

The present invention provides a method for producing a metal vapor that includes the steps of combining a metal and graphite in a vessel to form a mixture; heating the mixture to a first temperature in an argon gas atmosphere to form a metal carbide; maintaining the first temperature for a period of time; heating the metal carbide to a second temperature to form a metal vapor; withdrawing the metal vapor and the argon gas from the vessel; and separating the metal vapor from the argon gas. Metal vapors made using this method can be used to produce uniform powders of the metal oxide that have narrow size distribution and high purity.

Kunnmann, Walter (Stony Brook, NY); Larese, John Z. (Rocky Point, NY)

2001-01-01T23:59:59.000Z

49

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

DOE Patents (OSTI)

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

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

2009-10-13T23:59:59.000Z

50

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

51

Carbon-Supported bimetallic Pd-Fe catalysts for vapor-phase hydrodeoxygenation of guaiacol  

Science Conference Proceedings (OSTI)

Abstract Carbon supported metal catalysts (Cu/C, Fe/C, Pd/C, Pt/C, PdFe/C and Ru/C) have been prepared, characterized and tested for vapor-phase hydrodeoxygenation (HDO) of guaiacol (GUA) at atmospheric pressure. Phenol was the major intermediate on all catalysts. Over the noble metal catalysts saturation of the aromatic ring was the major pathway observed at low temperature (250 °C), forming predominantly cyclohexanone and cyclohexanol. Substantial ring opening reaction was observed on Pt/C and Ru/C at higher reaction temperatures (e.g., 350 °C). Base metal catalysts, especially Fe/C, were found to exhibit high HDO activity without ring-saturation or ring-opening with the main products being benzene, phenol along with small amounts of cresol, toluene and trimethylbenzene (TMB). A substantial enhancement in HDO activity was observed on the PdFe/C catalysts. Compared with Fe/C, the yield to oxygen-free aromatic products (i.e., benzene/toluene/TMB) on PdFe/C increased by a factor of four at 350 °C, and by approximately a factor of two (83.2% versus 43.3%) at 450 °C. The enhanced activity of PdFe/C is attributed to the formation of PdFe alloy as evidenced by STEM, EDS and TPR.

Sun, Junming; Karim, Ayman M.; Zhang, He; Kovarik, Libor; Li, Xiaohong S.; Hensley, Alyssa; McEwen, Jean-Sabin; Wang, Yong

2013-10-01T23:59:59.000Z

52

TREATMENT OF PRODUCED WATERS USING A SURFACTANT MODIFIED ZEOLITE/VAPOR PHASE BIOREACTOR SYSTEM  

DOE Green Energy (OSTI)

Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. It is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some of them must be treated to remove organic constituents before the water is discharged. Current treatment options are successful in reducing the organic content; however, they cannot always meet the levels of current or proposed regulations for discharged water. Therefore, an efficient, cost-effective treatment technology is needed. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. Our previous DOE research work (DE-AC26-99BC15221) demonstrated that SMZ could successfully remove BTEX compounds from the produced water. In addition, SMZ could be regenerated through a simple air sparging process. The primary goal of this project is to develop a robust SMZ/VPB treatment system to efficiently remove the organic constituents from produced water in a cost-effective manner. This report summarizes work of this project from October 2002 to March 2003. In this starting stage of this study, we have continued our investigation of SMZ regeneration from our previous DOE project. Two saturation/stripping cycles have been completed for SMZ columns saturated with BTEX compounds. Preliminary results suggest that BTEX sorption actually increases with the number of saturation/regeneration cycles. Furthermore, the experimental vapor phase bioreactors for this project have been designed and are currently being assembled to treat the off-gas from the SMZ regeneration process.

Lynn E. Katz; Kerry A. Kinney; R.S. Bowman; E.J. Sullivan

2003-04-01T23:59:59.000Z

53

Desalination-of water by vapor-phase transport through hydrophobic nanopores  

E-Print Network (OSTI)

We propose a new approach to desalination of water whereby a pressure difference across a vapor-trapping nanopore induces selective transport of water by isothermal evaporation and condensation across the pore. Transport ...

Lee, Jongho

54

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

DOE Green Energy (OSTI)

This report summarizes work performed on this project from October 2004 through March 2005. In previous work, a surfactant modified zeolite (SMZ) was shown to be an effective system for removing BTEX contaminants from produced water. Additional work on this project demonstrated that a compost-based biofilter could biodegrade the BTEX contaminants found in the SMZ regeneration waste gas stream. However, it was also determined that the BTEX concentrations in the waste gas stream varied significantly during the regeneration period and the initial BTEX concentrations were too high for the biofilter to handle effectively. A series of experiments were conducted to determine the feasibility of using a passive adsorption column placed upstream of the biofilter to attenuate the peak gas-phase VOC concentrations delivered to the biofilter during the SMZ regeneration process. In preparation for the field test of the SMZ/VPB treatment system in New Mexico, a pilot-scale SMZ system was also designed and constructed during this reporting period. Finally, a cost and feasibility analysis was also completed. To investigate the merits of the passive buffering system during SMZ regeneration, two adsorbents, SMZ and granular activated carbon (GAC) were investigated in flow-through laboratory-scale columns to determine their capacity to handle steady and unsteady VOC feed conditions. When subjected to a toluene-contaminated air stream, the column containing SMZ reduced the peak inlet 1000 ppmv toluene concentration to 630 ppmv at a 10 second contact time. This level of buffering was insufficient to ensure complete removal in the downstream biofilter and the contact time was longer than desired. For this reason, using SMZ as a passive buffering system for the gas phase contaminants was not pursued further. In contrast to the SMZ results, GAC was found to be an effective adsorbent to handle the peak contaminant concentrations that occur early during the SMZ regeneration process. At a one second residence time, the GAC bed reduced peak contaminant concentrations by 97%. After the initial peak, the inlet VOC concentration in the SMZ regeneration gas stream drops exponentially with time. During this period, the contaminants on the GAC subsequently desorbed at a nearly steady rate over the next 45 hours resulting in a relatively steady effluent concentration of approximately 25 ppm{sub v}. This lower concentration is readily degradable by a downstream vapor phase biofilter (VPB) and the steady nature of the feed stream will prevent the biomass in the VPB from enduring starvation conditions between SMZ regeneration cycles. Repetitive sorption and desorption cycles that would be expected in the field were also investigated. It was determined that although the GAC initially lost some VOC sorption capacity, the adsorption and desorption profiles stabilized after approximately 6 cycles indicating that a GAC bed should be suitable for continuous operation. In preparation for the pilot field testing of the SMZ/VPB system, design, ''in-house'' construction and testing of the field system were completed during this project period. The design of the SMZ system for the pilot test was based on previous investigations by the PI's in Wyoming, 2002 and on analyses of the produced water at the field site in New Mexico. The field tests are scheduled for summer, 2005. A cost survey, feasibility of application and cost analyses were completed to investigate the long term effectiveness of the SMZ/VPB system as a method of treating produced water for re-use. Several factors were investigated, including: current costs to treat and dispose of produced water, end-use water quality requirements, and state and federal permitting requirements.

Soondong Kwon; Elaine B. Darby; Li-Jung Chen; Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

2005-03-11T23:59:59.000Z

55

Treatment of Produced Water Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

DOE Green Energy (OSTI)

Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. Produced waters typically contain a high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component as well as chemicals added during the oil-production process. It has been estimated that a total of 14 billion barrels of produced water were generated in 2002 from onshore operations (Veil, 2004). Although much of this produced water is disposed via reinjection, environmental and cost considerations can make surface discharge of this water a more practical means of disposal. In addition, reinjection is not always a feasible option because of geographic, economic, or regulatory considerations. In these situations, it may be desirable, and often necessary from a regulatory viewpoint, to treat produced water before discharge. It may also be feasible to treat waters that slightly exceed regulatory limits for re-use in arid or drought-prone areas, rather than losing them to reinjection. A previous project conducted under DOE Contract DE-AC26-99BC15221 demonstrated that surfactant modified zeolite (SMZ) represents a potential treatment technology for produced water containing BTEX. Laboratory and field experiments suggest that: (1) sorption of benzene, toluene, ethylbenzene and xylenes (BTEX) to SMZ follows linear isotherms in which sorption increases with increasing solute hydrophobicity; (2) the presence of high salt concentrations substantially increases the capacity of the SMZ for BTEX; (3) competitive sorption among the BTEX compounds is negligible; and, (4) complete recovery of the SMZ sorption capacity for BTEX can be achieved by air sparging the SMZ. This report summarizes research for a follow on project to optimize the regeneration process for multiple sorption/regeneration cycles, and to develop and incorporate a vapor phase bioreactor (VPB) system for treatment of the off-gas generated during air sparging. To this end, we conducted batch and column laboratory SMZ and VPB experiments with synthetic and actual produced waters. Based on the results of the laboratory testing, a pilot scale study was designed and conducted to evaluate the combined SMZ/VPB process. An economic and regulatory feasibility analysis was also completed as part of the current study to assess the viability of the process for various water re-use options.

Lynn E. Katz; Kerry A. Kinney; Robert S. Bowman; Enid J. Sullivan; Soondong Kwon; Elaine B. Darby; Li-Jung Chen; Craig R. Altare

2006-01-31T23:59:59.000Z

56

TREATMENT OF PRODUCED WATERS USING A SURFACTANT MODIFIED ZEOLITE/VAPOR PHASE BIOREATOR SYSTEM  

DOE Green Energy (OSTI)

Co-produced water from the oil and gas industry is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some of them must be treated to remove organic constituents before the water is discharged. An efficient, cost-effective treatment technology is needed to remove these constituents. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. Our previous DOE research work (DE-AC26-99BC15221) demonstrated that SMZ could successfully remove BTEX compounds from the produced water. In addition, SMZ could be regenerated through a simple air sparging process. The primary goal of this project is to develop a robust SMZ/VPB treatment system to efficiently remove the organic constituents from produced water in a cost-effective manner. This report summarizes work of this project from March 2003 through September 2003. We have continued our investigation of SMZ regeneration from our previous DOE project. Ten saturation/stripping cycles have been completed for SMZ columns saturated with BTEX compounds. The results suggest that BTEX sorption capacity is not lost after ten saturation/regeneration cycles. The composition of produced water from a site operated by Crystal Solutions Ltd. in Wyoming has been characterized and was used to identify key semi-volatile components. Isotherms with selected semi-volatile components have been initiated and preliminary results have been obtained. The experimental vapor phase bioreactors for this project have been designed and assembled to treat the off-gas from the SMZ regeneration process. These columns will be used both in the laboratory and in the proposed field testing to be conducted next year. Innocula for the columns that degrade all of the BTEX columns have been developed.

LYNN E. KATZ; KERRY A. KINNEY; R.S. BOWMAN; E.J. SULLIVAN

2003-10-01T23:59:59.000Z

57

Evaluation of Catalysts from Different Origin for Vapor Phase Upgrading in Biomass Pyrolysis  

SciTech Connect

Liquid fuels and chemicals from biomass resources arouse much interests in research and development. Fast pyrolysis of biomass has the potential to effectively change solid biomass materials into liquid products. However, bio-oil from traditional pyrolysis processes is difficult to apply in industry, because of its complicated composition, high oxygen content, low stability, etc. Upgrading or refining of the bio-oil should be performed for industrial application of biomass pyrolysis. Often, the process would be done in a separate reactor downstream of the pyrolysis process. In this paper, a laboratory scale micro test facility was constructed, wherein the pyrolysis of pine and catalytic upgrading of the resulting vapors were closely coupled in one reactor. The composition of vapor effluent was monitored with a molecular beam mass spectrometer (MBMS) for the online evaluation of the catalyst performance. Catalysts from different origin were tested and compared for the effectiveness of pyrolysis vapor upgrading, namely commercial zeolites, Ni based steam reforming catalyst, CaO, MgO, and several laboratory-made catalysts. The reaction temperature for catalytic upgrading varied between 400 and 600 centigrade, and the gaseous residence time ranged from 0.1 second to above 2 second, to simulate the conditions in industrial application. It is revealed that some catalysts are active in transform most of primary biomass pyrolysis vapors into hydrocarbons, resulting in nonoxygenated products, which is beneficial for downstream utilization. Others are not as effective, results in minor improvement compared with blank test results.

Zhang, X.; Mukarakate, C.; Zheng, Z.; Nimlos, M.

2012-01-01T23:59:59.000Z

58

Vapor-Phase-Deposited Organosilane Coatings as "Hardening" Agents for High-Peak-Power Laser Optics  

Science Conference Proceedings (OSTI)

Multilayer-dielectric (MLD) diffraction gratings are used in high-power laser systems to compress laser-energy pulses. The peak power deliverable on target for these short-pulse petawatt class systems is limited by the laser-damage resistance of the optical components in the system, especially the MLD gratings. Recent experiments in our laboratory have shown that vapor treatment of MLD gratings at room temperature with organosilanes such as hexamethyldisilazane (HMDS) produces an increase in their damage threshold as compared to uncoated MLD grating control samples.

Marshall, K.L.; Culakova, Z.; Ashe, B.; Giacofei, C.; Rigatti, A.L.; Kessler, T.J.; Schmid, A.W.; Oliver, J.B.; Kozlov, A.

2008-01-07T23:59:59.000Z

59

Enhanced quality thin film Cu(In,Ga)Se.sub.2 for semiconductor device applications by vapor-phase recrystallization  

DOE Patents (OSTI)

Enhanced quality thin films of Cu.sub.w (In,Ga.sub.y)Se.sub.z for semiconductor device applications are fabricated by initially forming a Cu-rich, phase-separated compound mixture comprising Cu(In,Ga):Cu.sub.x Se on a substrate to form a large-grain precursor and then converting the excess Cu.sub.x Se to Cu(In,Ga)Se.sub.2 by exposing it to an activity of In and/or Ga, either in vapor In and/or Ga form or in solid (In,Ga).sub.y Se.sub.z. Alternatively, the conversion can be made by sequential deposition of In and/or Ga and Se onto the phase-separated precursor. The conversion process is preferably performed in the temperature range of about 300.degree.-600.degree. C., where the Cu(In,Ga)Se.sub.2 remains solid, while the excess Cu.sub.x Se is in a liquid flux. The characteristic of the resulting Cu.sub.w (In,Ga).sub.y Se.sub.z can be controlled by the temperature. Higher temperatures, such as 500.degree.-600.degree. C., result in a nearly stoichiometric Cu(In,Ga)Se.sub.2, whereas lower temperatures, such as 300.degree.-400.degree. C., result in a more Cu-poor compound, such as the Cu.sub.z (In,Ga).sub.4 Se.sub.7 phase.

Tuttle, John R. (Denver, CO); Contreras, Miguel A. (Golden, CO); Noufi, Rommel (Golden, CO); Albin, David S. (Denver, CO)

1994-01-01T23:59:59.000Z

60

Lattice-matched epitaxial GaInAsSb/GaSb thermophotovoltaic devices  

DOE Green Energy (OSTI)

The materials development of Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} alloys for lattice-matched thermophotovoltaic (TPV) devices is reported. Epilayers with cutoff wavelength 2--2.4 {micro}m at room temperature and lattice-matched to GaSb substrates were grown by both low-pressure organometallic vapor phase epitaxy and molecular beam epitaxy. These layers exhibit high optical and structural quality. For demonstrating lattice-matched thermophotovoltaic devices, p- and n-type doping studies were performed. Several TPV device structures were investigated, with variations in the base/emitter thicknesses and the incorporation of a high bandgap GaSb or AlGaAsSb window layer. Significant improvement in the external quantum efficiency is observed for devices with an AlGaAsSb window layer compared to those without one.

Wang, C.A.; Choi, H.K.; Turner, G.W.; Spears, D.L.; Manfra, M.J. [Massachusetts Inst. of Tech., Lexington, MA (United States). Lincoln Lab.; Charache, G.W. [Lockheed Martin, Inc., Schenectady, NY (United States)

1997-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

TEM Studies of Solid Phase Epitaxial Growth of 3C-SiC Thin Film on Si  

Science Conference Proceedings (OSTI)

Ag decorated Al nanoparticles as novel ink materials for printed electronics ... on Phase Stabilities for Electrode Materials of advanced Li-Ion Batteries.

62

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

SciTech Connect

This report summarizes work performed on this project from April 2004 through September 2004. Our previous work demonstrated that a polyurethane foam biofilter could successfully biodegrade the BTEX contaminants found in the SMZ regeneration waste gas stream. However, establishing the biomass on the polyurethane foam packing was relatively time consuming and daily recirculation of a concentrated nutrient solution was required for efficient operation of the foam biofilter. To simplify the start up and operating requirements of the biofilter system, a simple, compost-based biofilter was investigated for its ability to treat the BTEX contaminants generated during the SMZ regeneration process. The investigation of the compost biofilter was divided into three experimental phases that spanned 180 days of biofilter operation. During Phase 1, the biofilter was continuously supplied a BTEX-contaminated waste gas stream. During Phase 2, a series of periodic shutdown tests were conducted to assess how the biofilter responded when the BTEX feed was discontinued for periods ranging from 1 day to 2.8 days. The Phase 3 experiments focused on determining how the biofilter would handle periodic spikes in inlet BTEX concentration as would be expected when it is coupled with an SMZ column. Results from the continuous feed (Phase 1) experiments demonstrated that the compost biofilter could maintain BTEX removals of greater than 98% within two weeks of startup. Results of the shutdown experiments indicated that benzene removal was the most sensitive to interruptions in the BTEX feed. Nevertheless, the BTEX removal efficiency exceeded 95% within 6 hours of reestablishing the BTEX feed to the biofilter. When the biofilter was subjected to periodic spikes in BTEX concentration (Phase 3), it was found that the total BTEX removal efficiency stabilized at approximately 75% despite the fact that the biofilter was only fed BTEX contaminants 8 hours per day. Finally, the effects of nutrient supply and EBCT on compost biofilter performance were also investigated. The bioreactor maintained greater than 95% removal efficiency for over 40 days without an additional supply of nutrients when a 10X concentrated HCMM was mixed with the compost packing at the beginning of the experiments. Results also suggest that an EBCT greater than 30 seconds is required to maintain high BTEX removal efficiencies in the compost biofilter system.

Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

2004-09-11T23:59:59.000Z

63

Relaxation and critical strain for maximum In incorporation in AlInGaN on GaN grown by metal organic vapour phase epitaxy  

Science Conference Proceedings (OSTI)

Quaternary AlInGaN layers were grown on conventional GaN buffer layers on sapphire by metal organic vapour phase epitaxy at different surface temperatures and different reactor pressures with constant precursor flow conditions. A wide range in compositions within 30-62% Al, 5-29% In, and 23-53% Ga was covered, which leads to different strain states from high tensile to high compressive. From high-resolution x-ray diffraction and Rutherford backscattering spectrometry, we determined the compositions, strain states, and crystal quality of the AlInGaN layers. Atomic force microscopy measurements were performed to characterize the surface morphology. A critical strain value for maximum In incorporation near the AlInGaN/GaN interface is presented. For compressively strained layers, In incorporation is limited at the interface as residual strain cannot exceed an empirical critical value of about 1.1%. Relaxation occurs at about 15 nm thickness accompanied by strong In pulling. Tensile strained layers can be grown pseudomorphically up to 70 nm at a strain state of 0.96%. A model for relaxation in compressively strained AlInGaN with virtual discrete sub-layers, which illustrates the gradually changing lattice constant during stress reduction is presented.

Reuters, Benjamin; Finken, M.; Wille, A.; Kalisch, H.; Vescan, A. [RWTH Aachen University, GaN Device Technology, Sommerfeldstrasse 24, 52074 Aachen (Germany); Juelich Aachen Research Alliance, JARA-FIT, Wilhelm-Johnen-Strasse, 52428 Juelich (Germany); Hollaender, B. [Juelich Aachen Research Alliance, JARA-FIT, Wilhelm-Johnen-Strasse, 52428 Juelich (Germany); Forschungszentrum Juelich GmbH, PGI9-IT, 52425 Juelich (Germany); Heuken, M. [RWTH Aachen University, GaN Device Technology, Sommerfeldstrasse 24, 52074 Aachen (Germany); AIXTRON SE, Kaiserstr. 98, 52134 Herzogenrath (Germany)

2012-11-01T23:59:59.000Z

64

Transition between the 1 x 1 and ({radical}3 x 2{radical}3)R30{degree} surface structures of GaN in the vapor-phase environment  

SciTech Connect

Out-of-plane structures of the GaN(0001) surface in the metal-organic chemical vapor deposition (MOCVD) environment have been determined using in situ grazing-incidence X-ray scattering. The authors measured 11{bar 2}{ell} crystal truncation rod intensities at a variety of temperatures and ammonia partial pressures on both sides of the 1 x 1 to ({radical}3 x 2{radical}3)R30{degree} surface phase transition. The out-of-plane structure of the ({radical}3 x 2{radical}3)R30{degree} phase appears to be nearly independent of temperature below the transition, while the structure of the 1 x 1 phase changes increase rapidly as the phase transition is approached from above. A model for the structure of the 1 x 1 phase with a partially-occupied top Ga layer agrees well with the data. The observed temperature dependence is consistent with a simple model of the equilibrium between the vapor phase and the surface coverage of Ga and N. In addition, the authors present results on the kinetics of reconstruction domain coarsening following a quench into the ({radical}3 x 2{radical}3)R30{degree} phase field.

Munkholm, A.; Thompson, C.; Stephenson, G. B.; Eastman, J. A.; Auciello, O.; Fini, P.; Speck, J. S.; DenBaars, S. P.

2000-01-12T23:59:59.000Z

65

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

66

GaAs/AIGaAs quantum well and modulation-doped heterostructures grown by organometallic vapor phase epitaxy using trimethylamine alane  

E-Print Network (OSTI)

describedpreviously.6 The carrier gaswashydrogenand the sourcereagentswere arsine,TEGa, andTMAA. Disilane wasutilized

Florida, University of

67

Ferromagnetism in Mn-Implanted Epitaxially Grown Ge on Si(100)  

SciTech Connect

We have studied ferromagnetism of Mn-implanted epitaxial Ge films on silicon. The Ge films were grown by ultrahigh vacuum chemical vapor deposition using a mixture of germane (GeH{sub 4}) and methylgermane (CH{sub 3}GeH{sub 3}) gases with a carbon concentration of less than 1 at. %, and observed surface rms roughness of 0.5 nm, as measured by atomic force microscopy. Manganese ions were implanted in epitaxial Ge films grown on Si (100) wafers to an effective concentration of 16, 12, 6, and 2 at. %. Superconducting quantum interference device measurements showed that only the three highest Mn concentration samples are ferromagnetic, while the fourth sample, with [Mn] = 2 at. %, is paramagnetic. X-ray absorption spectroscopy and x-ray magnetic circular dichroism measurements indicate that localized Mn moments are ferromagnetically coupled below the Curie temperature. Isothermal annealing of Mn-implanted Ge films with [Mn] = 16 at. % at 300 C for up to 1200 s decreases the magnetization but does not change the Curie temperature, suggesting that the amount of the magnetic phase slowly decreases with time at this anneal temperature. Furthermore, transmission electron microscopy and synchrotron grazing incidence x-ray diffraction experiments show that the Mn-implanted region is amorphous, and we believe that it is this phase that is responsible for the ferromagnetism. This is supported by our observation that high-temperature annealing leads to recrystallization and transformation of the material into a paramagnetic phase.

Guchhait, S.; Jamil, M.; Ohldag, H.; Mehta, A.; Arenholz, E.; Lian, G.; Li Fatou, A.; Ferrer, D. A.; Markert, J. T.; Colombo, L.; Banerjee, S. K.

2011-01-05T23:59:59.000Z

68

Vapor Degreasing  

Science Conference Proceedings (OSTI)

Table 6   Applications of vapor degreasing by vapor-spray-vapor systems...hardware Brass 2270 5000 Buffing compound; rouge Lacquer spray Racked work on continuous monorail Acoustic ceiling tile Steel 2720 6000 Light oil (stamping lubricant) Painting Monorail conveyor Gas meters Terneplate 4540 10,000 Light oil Painting Monorail conveyor Continuous strip, 0.25â??4.1 mm...

69

Vapor Characterization  

Science Conference Proceedings (OSTI)

... thermodynamics (that is, vapor liquid equilibrium) as ... of solids and low volatility liquids is extraordinarily ... such situations is the gas saturation method ...

2013-12-10T23:59:59.000Z

70

Determination of the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon using thermogravimetric analysis  

Science Conference Proceedings (OSTI)

This study investigated the use of thermogravimetric analysis (TGA) to determine the adsorptive capacity and adsorption isotherm of vapor-phase mercury chloride on powdered activated carbon (PAC). The technique is commonly applied to remove mercury-containing air pollutants from gas streams emitted from municipal solid waste incinerators. An alternative form of powdered activated carbon derived from a pyrolyzed tire char was prepared for use herein. The capacity of waste tire-derived PAC to adsorb vapor-phase HgCl{sub 2} was successfully measured using a self-designed TGA adsorption system. Experimental results showed that the maximum adsorptive capacities of HgCl{sub 2} were 1.75, 0.688, and 0.230 mg of HgCl{sub 2} per gram of powdered activated carbon derived from carbon black at 30, 70, and 150{sup o} for 500 {mu}g/m{sup 3} of HgCl{sub 2}, respectively. Four adsorption isotherms obtained using the Langmuir, Freundlich, Redlich-Peterson, and Brunauer-Emmett-eller (BET) models were used to simulate the adsorption of HgCl{sub 2}. The comparison of experimental data associated with the four adsorption isotherms indicated that BET fit the experimental results better than did the other isotherms at 30{sup o}, whereas the Freundlich isotherm fit the experimental results better at 70 and 150{sup o}. Furthermore, the calculations of the parameters associated with Langmuir and Freundlich isotherms revealed that the adsorption of HgCl{sub 2} by PAC-derived carbon black favored adsorption at various HgCl{sub 2} concentrations and temperatures. 35 refs., 7 figs., 3 tabs.

Hsun-Yu Lin; Chung-Shin Yuan; Wei-Ching Chen; Chung-Hsuang Hung [National Sun Yat-Sen University, Taiwan (China). Institute of Environmental Engineering

2006-11-15T23:59:59.000Z

71

Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from Ethanol/Gasoline Fuels, Phase 2: Evaluations of Field Samples and Laboratory Blends  

DOE Green Energy (OSTI)

Study to measure the flammability of gasoline/ethanol fuel vapors at low ambient temperatures and develop a mathematical model to predict temperatures at which flammable vapors were likely to form.

Gardiner, D. P.; Bardon, M. F.; LaViolette, M.

2010-04-01T23:59:59.000Z

72

Substrate misorientation effects on epitaxial GaInAsSb  

DOE Green Energy (OSTI)

The effect of substrate misorientation on the growth of GaInAsSb was studied for epilayers grown lattice-matched to GaSb substrates by low-pressure organometallic vapor phase epitaxy. The substrates were (100) misoriented 2 or 6{degree} toward (110), (111)A, or (111)B. The surface is mirror-like and featureless for layers grown with a 6{degree} toward (111)B misorientation, while, a slight texture was observed for layers grown on all other misorientations. The optical quality of layers, as determined by the full width at half-maximum of photoluminescence spectra measured at 4K, is significantly better for layers grown on substrates with a 6{degree} toward (111)B misorientation. The incorporation of Zn as a p-type dopant in GaInAsSb is about 1.5 times more efficient on substrates with 6{degree} toward (111)B misorientation compared to 2{degree} toward (110) misorientation. The external quantum efficiency of thermophotovoltaic devices is not, however, significantly affected by substrate misorientation.

Wang, C.A.; Choi, H.K.; Oakley, D.C. [Massachusetts Inst. of Tech., Lexington, MA (United States). Lincoln Lab.; Charache, G.W. [Lockheed Martin Corp., Schenectady, NY (United States)

1997-12-01T23:59:59.000Z

73

Epitaxial growth of Dy2O3 thin films on epitaxial Dy-germanide films on Ge(001) substrates  

Science Conference Proceedings (OSTI)

Ultra-thin films of Dy are grown on Ge(001) substrates by molecular beam deposition near room temperature and immediately annealed for solid phase epitaxy at higher temperatures, leading to the formation of DyGe"x films. Thin films of Dy"2O"3 are grown ... Keywords: Dy2O3 film, Ge(001) substrate, High-? oxide, Molecular beam epitaxy (MBE), Structural characterization, Transmission electron microscopy (TEM)

Md. Nurul Kabir Bhuiyan; Mariela Menghini; Jin Won Seo; Jean-Pierre Locquet

2011-04-01T23:59:59.000Z

74

Abstract--Selective epitaxial growth of crystalline Ge on Si in a standard ASM Epsilon 2000 CVD reactor is investigated for the  

E-Print Network (OSTI)

In a standard CVD reactor, Ge selective epitaxial growth on patterned Si substrates was developed in thickness. The epitaxy is performed in a standard ASM Epsilon 2000 chemical-vapor-deposition (CVD) reactor surface after Ge-growth make this an attractive and straightforward add-on to standard Si technology. #12

Technische Universiteit Delft

75

Growth of pseudomorphic structures through organic epitaxy  

SciTech Connect

The control of molecular orientation in thin solid film phases of organic semiconductors is a basic factor for the exploitation of their physical properties for optoelectronic devices. We compare structural and optical properties of thin films of the organic semiconductor {alpha}-quarterthiophene grown by molecular beam epitaxy on different organic substrates. We show how epitactic interactions, characteristic of the surface of organic crystals, can drive the orientation of the crystalline overlayer and the selection of specific polymorphs and new pseudomorphic phases. We identify a key role in this phenomenon played by the marked groove-like corrugations present in some organic crystal surfaces. Since different polymorphs possess rather different performance in terms of, e.g., charge carrier mobility, this strategy is demonstrated to allow for the growth of oriented phases with enhanced physical properties, while keeping the substrate at room temperature. These results provide useful guidelines for the design of technological substrates for organic epitaxy and they substantiate the adoption of an organic epitaxy approach for the fabrication of optoelectronic devices based on thin films of organic semiconductors.

Kaviyil, Sreejith Embekkat; Sassella, Adele; Borghesi, Alessandro [Department of Materials Science, Universita degli Studi di Milano Bicocca, Via R. Cozzi 53, I-20125 Milan (Italy); Campione, Marcello [Department of Earth and Environmental Sciences, Universita degli Studi di Milano Bicocca, Piazza della Scienza 4, I-20126 Milan (Italy); Su Genbo; He Youping [Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science, Fuzhou 350002 (China); Chen Chenjia [Department of Physics, Peking University, Beijing 100871 (China)

2012-12-14T23:59:59.000Z

76

Epitaxial CoSi2 on MOS devices  

DOE Patents (OSTI)

An Si.sub.x N.sub.y or SiO.sub.x N.sub.y liner is formed on a MOS device. Cobalt is then deposited and reacts to form an epitaxial CoSi.sub.2 layer underneath the liner. The CoSi.sub.2 layer may be formed through a solid phase epitaxy or reactive deposition epitaxy salicide process. In addition to high quality epitaxial CoSi.sub.2 layers, the liner formed during the invention can protect device portions during etching processes used to form device contacts. The liner can act as an etch stop layer to prevent excessive removal of the shallow trench isolation, and protect against excessive loss of the CoSi.sub.2 layer.

Lim, Chong Wee (Urbana, IL); Shin, Chan Soo (Daejeon, KR); Petrov, Ivan Georgiev (Champaign, IL); Greene, Joseph E. (Champaign, IL)

2005-01-25T23:59:59.000Z

77

Quantitative Vapor-phase IR Intensities and DFT Computations to Predict Absolute IR Spectra based on Molecular Structure: I. Alkanes  

SciTech Connect

Recently recorded quantitative IR spectra of a variety of gas-phase alkanes are shown to have integrated intensities in both the C-H stretching and C-H bending regions that depend linearly on the molecular size, i.e. the number of C-H bonds. This result is well predicted from CH4 to C15H32 by DFT computations of IR spectra at the B3LYP/6-31+G(d,p) level of DFT theory. A simple model predicting the absolute IR band intensities of alkanes based only on structural formula is proposed: For the C-H stretching band near 2930 cm-1 this is given by (in km/mol): CH¬_str = (34±3)*CH – (41±60) where CH is number of C-H bonds in the alkane. The linearity is explained in terms of coordinated motion of methylene groups rather than the summed intensities of autonomous -CH2- units. The effect of alkyl chain length on the intensity of a C-H bending mode is explored and interpreted in terms of conformer distribution. The relative intensity contribution of a methyl mode compared to the total C-H stretch intensity is shown to be linear in the number of terminal methyl groups in the alkane, and can be used to predict quantitative spectra a priori based on structure alone.

Williams, Stephen D.; Johnson, Timothy J.; Sharpe, Steven W.; Yavelak, Veronica; Oats, R. P.; Brauer, Carolyn S.

2013-11-13T23:59:59.000Z

78

Impact of nonaqueous phase liquid (NAPL) source zone architecture on mass removal mechanisms in strongly layered heterogeneous porous media during soil vapor extraction  

Science Conference Proceedings (OSTI)

An existing multiphase flow simulator was modified in order to determine the effects of four mechanisms on NAPL mass removal in a strongly layered heterogeneous vadose zone during soil vapor extraction (SVE): a) NAPL flow, b) diffusion and dispersion from low permeability zones, c) slow desorption from sediment grains, and d) rate-limited dissolution of trapped NAPL. The impact of water and NAPL saturation distribution, NAPL type (i.e., free, residual, or trapped) distribution, and spatial heterogeneity of the permeability field on these mechanisms were evaluated. Two different initial source zone architectures (one with and one without trapped NAPL) were considered and these architectures were used to evaluate seven different SVE scenarios. For all runs, slow diffusion from low permeability zones that gas flow bypassed was a dominant factor for diminished SVE effectiveness at later times. This effect was more significant at high water saturation due to the decrease of gas-phase relative permeability. Transverse dispersion contributed to fast NAPL mass removal from the low permeability layer in both source zone architectures, but longitudinal dispersion did not affect overall mass removal time. Both slow desorption from sediment grains and rate-limited mass transfer from trapped NAPL only marginally affected removal times. However, mass transfer from trapped NAPL did affect mass removal at late time, as well as the NAPL distribution. NAPL flow from low to high permeability zones contributed to faster mass removal from the low permeability layer, and this effect increased when water infiltration was eliminated. These simulations indicate that if trapped NAPL exists in heterogeneous porous media, mass transfer can be improved by delivering gas directly to zones with trapped NAPL and by lowering the water content, which increases the gas relative permeability and changes trapped NAPL to free NAPL.

Yoon, Hongkyu; Werth, Charlie; Valocchi, Albert J.; Oostrom, Martinus

2008-09-26T23:59:59.000Z

79

Long Term Field Development of a Surfactant Modified Zeolite/Vapor Phase Bioreactor System for Treatment of Produced Waters for Power Generation  

Science Conference Proceedings (OSTI)

The main goal of this research was to investigate the feasibility of using a combined physicochemical/biological treatment system to remove the organic constituents present in saline produced water. In order to meet this objective, a physical/chemical adsorption process was developed and two separate biological treatment techniques were investigated. Two previous research projects focused on the development of the surfactant modified zeolite adsorption process (DE-AC26-99BC15221) and development of a vapor phase biofilter (VPB) to treat the regeneration off-gas from the surfactant modified zeolite (SMZ) adsorption system (DE-FC26-02NT15461). In this research, the SMZ/VPB was modified to more effectively attenuate peak loads and to maintain stable biodegradation of the BTEX constituents from the produced water. Specifically, a load equalization system was incorporated into the regeneration flow stream. In addition, a membrane bioreactor (MBR) system was tested for its ability to simultaneously remove the aromatic hydrocarbon and carboxylate components from produced water. The specific objectives related to these efforts included the following: (1) Optimize the performance VPBs treating the transient loading expected during SMZ regeneration: (a) Evaluate the impact of biofilter operating parameters on process performance under stable operating conditions. (b) Investigate how transient loads affect biofilter performance, and identify an appropriate technology to improve biological treatment performance during the transient regeneration period of an SMZ adsorption system. (c) Examine the merits of a load equalization technology to attenuate peak VOC loads prior to a VPB system. (d) Evaluate the capability of an SMZ/VPB to remove BTEX from produced water in a field trial. (2) Investigate the feasibility of MBR treatment of produced water: (a) Evaluate the biodegradation of carboxylates and BTEX constituents from synthetic produced water in a laboratory-scale MBR. (b) Evaluate the capability of an SMZ/MBR system to remove carboxylates and BTEX from produced water in a field trial. Laboratory experiments were conducted to provide a better understanding of each component of the SMZ/VPB and SMZ/MBR process. Laboratory VPB studies were designed to address the issue of influent variability and periodic operation (see DE-FC26-02NT15461). These experiments examined multiple influent loading cycles and variable concentration loadings that simulate air sparging as the regeneration option for the SMZ system. Two pilot studies were conducted at a produced water processing facility near Farmington, New Mexico. The first field test evaluated SMZ adsorption, SMZ regeneration, VPB buffering, and VPB performance, and the second test focused on MBR and SMZ/MBR operation. The design of the field studies were based on the results from the previous field tests and laboratory studies. Both of the biological treatment systems were capable of removing the BTEX constituents in the laboratory and in the field over a range of operating conditions. For the VPB, separation of the BTEX constituents from the saline aqueous phase yielded high removal efficiencies. However, carboxylates remained in the aqueous phase and were not removed in the combined VPB/SMZ system. In contrast, the MBR was capable of directly treating the saline produced water and simultaneously removing the BTEX and carboxylate constituents. The major limitation of the MBR system is the potential for membrane fouling, particularly when the system is treating produced water under field conditions. The combined process was able to effectively pretreat water for reverse osmosis treatment and subsequent downstream reuse options including utilization in power generation facilities. The specific conclusions that can be drawn from this study are summarized.

Lynn Katz; Kerry Kinney; Robert Bowman; Enid Sullivan; Soondong Kwon; Elaine Darby; Li-Jung Chen; Craig Altare

2007-12-31T23:59:59.000Z

80

Clusters and Magnetism in Epitaxial Co-doped TiO? Anatase.  

SciTech Connect

We show that under certain conditions, highly Co-enriched Ti0? anatase clusters nucleate on epitaxial Ti0? anatase grown on LaA?O?(001) by oxygen plasma assisted molecular beam epitaxy. In the most extreme cases, virtually all incident Co segregates to the clusters, yielding a nanoscale ferromagnitic phase that is not ferromagnetic in homogeneous films of the same Co concentration. The nucleation of this phase simultaneous with continuous epitaxial film growth must be carefully monitored in order to avoid drawing false conclusions about the film structure

Chambers, Scott A.; Droubay, Timothy; Wang, Chong M.; Lea, Alan S.; Farrow, R.F.C; Folks, L.; Deline, V.; Anders, S.

2003-02-24T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Image Storage in Hot Vapors  

E-Print Network (OSTI)

We theoretically investigate image propagation and storage in hot atomic vapor. A $4f$ system is adopted for imaging and an atomic vapor cell is placed over the transform plane. The Fraunhofer diffraction pattern of an object in the object plane can thus be transformed into atomic Raman coherence according to the idea of ``light storage''. We investigate how the stored diffraction pattern evolves under diffusion. Our result indicates, under appropriate conditions, that an image can be reconstructed with high fidelity. The main reason for this procedure to work is the fact that diffusion of opposite-phase components of the diffraction pattern interfere destructively.

Zhao, L; Xiao, Y; Yelin, S F

2007-01-01T23:59:59.000Z

82

Image Storage in Hot Vapors  

E-Print Network (OSTI)

We theoretically investigate image propagation and storage in hot atomic vapor. A $4f$ system is adopted for imaging and an atomic vapor cell is placed over the transform plane. The Fraunhofer diffraction pattern of an object in the object plane can thus be transformed into atomic Raman coherence according to the idea of ``light storage''. We investigate how the stored diffraction pattern evolves under diffusion. Our result indicates, under appropriate conditions, that an image can be reconstructed with high fidelity. The main reason for this procedure to work is the fact that diffusion of opposite-phase components of the diffraction pattern interfere destructively.

L. Zhao; T. Wang; Y. Xiao; S. F. Yelin

2007-10-22T23:59:59.000Z

83

Calibrated vapor generator source  

DOE Patents (OSTI)

A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet.

Davies, John P. (Idaho Falls, ID); Larson, Ronald A. (Idaho Falls, ID); Goodrich, Lorenzo D. (Shelley, ID); Hall, Harold J. (Idaho Falls, ID); Stoddard, Billy D. (Idaho Falls, ID); Davis, Sean G. (Idaho Falls, ID); Kaser, Timothy G. (Idaho Falls, ID); Conrad, Frank J. (Albuquerque, NM)

1995-01-01T23:59:59.000Z

84

Calibrated vapor generator source  

DOE Patents (OSTI)

A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet. 10 figs.

Davies, J.P.; Larson, R.A.; Goodrich, L.D.; Hall, H.J.; Stoddard, B.D.; Davis, S.G.; Kaser, T.G.; Conrad, F.J.

1995-09-26T23:59:59.000Z

85

Pine Pyrolysis Vapor Phase Upgrading Over ZSM-5 Catalyst: Effect of Temperature, Hot Gas Filtration, and Hydrogen Donor Molecule on the Rate of Deactivation of Catalyst  

SciTech Connect

The conversion of primary vapors from pine pyrolysis over a ZSM-5 catalyst was characterized using a micro-reactor coupled to a molecular beam mass spectrometer (MBMS) to allow on-line measurement of the upgraded vapors. This micro-reacor-MBMS system was used to investigate the effects of hot gas filtration, temperature and hydrogen donor molecules on the rate of deactivation of the UPV2 catalyst. Our results show that the life of catalyst is significantly improved by using better filtration. Temperature had an effect on both product distribution and catalyst deactivation. The hydrogen donor molecules (HDM) used in this study show better reduction in catalyst deactivation rates at high temperatures.

Mukarakate, C.; Zhang, X.; Nimlos, M.; Robichaud, D.; Donohoe, B.

2013-01-01T23:59:59.000Z

86

Magnetic behaviour of europium epitaxial thin films  

Science Conference Proceedings (OSTI)

... Magnetic behaviour of europium epitaxial thin films. Philippe Mangin, University of Nancy and NCNR. We present the magnetic ...

87

Epitaxial Graphene: Designing a New Electronic Material  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2010 Electronic Materials Conference. Symposium, TMS 2010 Electronic Materials Conference. Presentation Title, Epitaxial ...

88

The Controller Synthesis of Metastable Oxides Utilizing Epitaxy and Epitaxial Stabilization  

SciTech Connect

Molecular beam epitaxy (MBE) has achieved unparalleled control in the integration of semiconductors at the nanometer. These advances were made through the use of epitaxy, epitaxial stabilization, and a combination of composition-control techniques including adsorption-controlled growth and RHEED-based composition control that we have developed, understood, and utilized for the growth of oxides. Also key was extensive characterization (utilizing RHEED, four-circle x-ray diffraction, AFM, TEM, and electrical characterization techniques) in order to study growth modes, optimize growth conditions, and probe the structural, dielectric, and ferroelectric properties of the materials grown. The materials that we have successfully engineered include titanates (PbTiO3, Bi4Ti3O12), tantalates (SrBi2Ta2O9), and niobates (SrBi2Nb2O9); layered combinations of these perovskite-related materials (Bi4Ti3O12-SrTiO3 and Bi4Ti3O12-PbTiO3 Aurivillius phases and metastable PbTiO3/SrTiO3 and BaTiO3/SrTiO3 superlattices), and new metastable phases (Srn+1TinO3n+1 Ruddlesden-Popper phases). The films were grown by reactive MBE and pulsed laser deposition (PLD). Many of these materials are either new or have been synthesized with the highest perfection ever reported. The controlled synthesis of such layered oxide heterostructures offers great potential for tailoring the superconducting, ferroelectric, and dielectric properties of these materials. These properties are important for energy technologies.

Schlom, Darrell

2003-12-02T23:59:59.000Z

89

Mercury Vapor Pressure Correlation  

Science Conference Proceedings (OSTI)

An apparent difference between the historical mercury vapor concentration equations used by the mercury atmospheric measurement community ...

2012-10-09T23:59:59.000Z

90

Multicomponent fuel vaporization at high pressures.  

DOE Green Energy (OSTI)

We extend our multicomponent fuel model to high pressures using a Peng-Robinson equation of state, and implement the model into KIVA-3V. Phase equilibrium is achieved by equating liquid and vapor fugacities. The latent heat of vaporization and fuel enthalpies are also corrected for at high pressures. Numerical simulations of multicomponent evaporation are performed for single droplets for a diesel fuel surrogate at different pressures.

Torres, D. J. (David J.); O'Rourke, P. J. (Peter J.)

2002-01-01T23:59:59.000Z

91

Urania vapor composition at very high temperatures  

SciTech Connect

Due to the chemically unstable nature of uranium dioxide its vapor composition at very high temperatures is, presently, not sufficiently studied though more experimental knowledge is needed for risk assessment of nuclear reactors. We used laser vaporization coupled to mass spectrometry of the produced vapor to study urania vapor composition at temperatures in the vicinity of its melting point and higher. The very good agreement between measured melting and freezing temperatures and between partial pressures measured on the temperature increase and decrease indicated that the change in stoichiometry during laser heating was very limited. The evolutions with temperature (in the range 2800-3400 K) of the partial pressures of the main vapor species (UO{sub 2}, UO{sub 3}, and UO{sub 2}{sup +}) were compared with theoretically predicted evolutions for equilibrium noncongruent gas-liquid and gas-solid phase coexistences and showed very good agreement. The measured main relative partial pressure ratios around 3300 K all agree with calculated values for total equilibrium between condensed and vapor phases. It is the first time the three main partial pressure ratios above stoichiometric liquid urania have been measured at the same temperature under conditions close to equilibrium noncongruent gas-liquid phase coexistence.

Pflieger, Rachel [Institute for Transuranium Elements, Joint Research Centre, European Commission, P.O. Box 2340, 76125 Karlsruhe (Germany); Marcoule Institute for Separation Chemistry (ICSM), UMR 5257, CEA-CNRS-UMII-ENSCM, Bagnols sur Ceze Cedex (France); Colle, Jean-Yves [Institute for Transuranium Elements, Joint Research Centre, European Commission, P.O. Box 2340, 76125 Karlsruhe (Germany); Iosilevskiy, Igor [Joint Institute for High Temperature, Russian Academy of Science, 125412 Moscow (Russian Federation); Moscow Institute of Physics and Technology, State University, 141700 Moscow (Russian Federation); Extreme Matter Institute (EMMI), 64291 Darmstadt (Germany); Sheindlin, Michael [Institute for Transuranium Elements, Joint Research Centre, European Commission, P.O. Box 2340, 76125 Karlsruhe (Germany); Joint Institute for High Temperature, Russian Academy of Science, 125412 Moscow (Russian Federation)

2011-02-01T23:59:59.000Z

92

Development of a polysilicon process based on chemical vapor deposition. Phase 1. Fourth quarterly progress report, 1 July-30 September 1980  

DOE Green Energy (OSTI)

The goal of this program is to demonstrate that a dichlorosilane-based reductive chemical vapor deposition (CVD) process is capable of producing, at low cost, high quality polycrystalline silicon for use in the manufacture of high efficiency solar cells. The feasibility of silicon generation from dichlorosilane (DCS) has been well established. The feasibility and optimization portions of the experimental reactor program have been completed, with a number of runs having been conducted over a broad range of conditions in an experimental CVD reactor. Activities relating to feed of commercially purchased DCS to an intermediate sized reactor and to construction of a Process Development Unit (PDU) to generate and feed DCS to one or more production scale reactors were suspended during the previous quarter because of the receipt of new safety-related information about DCS from Hazards Research Corp. Experimental data generated by Hazards Research Corp. indicate that DCS/air mixtures possess about four times the explosive severity potential as hydrogen/air mixtures, and that DCS/air mixtures are very readily ignited. As a consequence of this new information, designs and procedures for the intermediate reactor feed and PDU tasks were deemed inadequate and new designs incorporating new safety-related elements are being formulated. A preliminary economic evaluation of the Hemlock Semiconductor process has been completed. The analysis for a plant to generate 1000 metric tonne of silicon indicates a plant investment of $21.9 M, and a product selling price of $19.85/kg.

Sharp, K.; Arvidson, A.; Sawyer, D.

1980-12-01T23:59:59.000Z

93

Development of a polysilicon process based on chemical vapor deposition (Phase 1). First quarterly progress report, 6 October-31 December 1979  

DOE Green Energy (OSTI)

The goal of this program is to demonstrate that a dichlorosilane based reductive chemical vapor deposition (CVD) process is capable of producing, at low cost, high quality polycrystalline silicon. Physical form and purity of this material will be consistent with LSA material requirements for use in the manufacture of high efficiency solar cells. Chemical processes involved in achieving the objective are reviewed with emphasis placed on advantages of this process when compared with existing polycrystalline silicon production technology. Installation of a CVD reactor with associated analytical instrumentation is described. Preliminary reactor data has been favorable demonstrating the anticipated increased deposition rate and conversion efficiency when dichlorosilane decomposition is compared with trichlorosilane decomposition. No serious problems have been encountered which might limit dichlorosilane use as a reactor feed material. Design considerations for a process development unit (PDU) for dichlorosilane synthesis are reviewed. A design which effectively suppresses monochlorosilane during the redistribution of trichlorosilane was decided upon and its implementation is described. The PDU will be used to collect data on optimization of the redistribution process as well as to determine product quality. Based on experimental data collected during the first quarter along with already available data on the redistribution and hydrogenation processes, a preliminary mass balance is established.

McCormick, J. R.; Arvidson, A.; Plahutnik, F.; Sawyer, D.; Sharp, K.

1980-01-01T23:59:59.000Z

94

Vapor spill monitoring method  

DOE Patents (OSTI)

Method for continuous sampling of liquified natural gas effluent from a spill pipe, vaporizing the cold liquified natural gas, and feeding the vaporized gas into an infrared detector to measure the gas composition. The apparatus utilizes a probe having an inner channel for receiving samples of liquified natural gas and a surrounding water jacket through which warm water is flowed to flash vaporize the liquified natural gas.

Bianchini, Gregory M. (Livermore, CA); McRae, Thomas G. (Livermore, CA)

1985-01-01T23:59:59.000Z

95

Transmission Electron Microscopy Study of Nonpolar a-Plane GaN Grown by Pendeo-Epitaxy on (112_0) 4H-SiC  

E-Print Network (OSTI)

by Pendeo-Epitaxy on (1120) 4H-SiC. D.N. Zakharov 1 , Z.phase epitaxy on (1120) 4H-SiC substrates with AlN bufferPE layers were grown on 4H- SiC (1120) substrates previously

Zakharov, D.N.; Liliental-Weber, Z.; Wagner, B.; Reitmeier, Z.J.; Preble, E.A.; Davis, R.F.

2008-01-01T23:59:59.000Z

96

Aerogel composites using chemical vapor infiltration  

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

Aerogel composites using chemical vapor infiltration Aerogel composites using chemical vapor infiltration Title Aerogel composites using chemical vapor infiltration Publication Type Journal Article Year of Publication 1995 Authors Hunt, Arlon J., Michael R. Ayers, and Wanqing Cao Journal Journal of Non-Crystalline Solids Volume 185 Pagination 227-232 Abstract A new method to produce novel composite materials based on the use of aerogels as a starting material is described. Using chemical vapor infiltration, a variety of solid materials were thermally deposited into the open pore structure of aerogel. The resulting materials possess new and unusual properties including photoluminescence, magnetism and altered optical properties. An important characteristic of this preparation process is the very small size of the deposits that gives rise to new behaviors. Silicon deposits exhibit photoluminescence, indicating quantum confinement. Two or more phases may be deposited simultaneously and one or both chemically or thermally reacted to produce new structures.

97

Distributions of Liquid, Vapor, and Ice in an Orographic Cloud from Field Observations  

Science Conference Proceedings (OSTI)

The phase distribution of the water mass of a cold orographic cloud into vapor, liquid, and ice is calculated from measurements made from an instrumented aircraft. The vapor values are calculated from thermodynamic measurements, and the liquid is ...

Taneil Uttal; Robert M. Rauber; Lewis O. Grant

1988-04-01T23:59:59.000Z

98

Low temperature metal-organic chemical vapor deposition growth processes for high-efficiency solar cells  

DOE Green Energy (OSTI)

This report describes the results of a program to develop a more complete understanding of the physical and chemical processes involved in low-temperature growth of III-V compounds by metal-organic chemical vapor deposition (MOCVD) and to develop a low-temperature process that is suitable for the growth of high-efficiency solar cells. The program was structured to develop a better understanding of the chemical reactions involved in MOCVD growth, to develop a model of the processes occurring in the gas phase, to understand the physical kinetics and reactions operative on the surface of the growing crystal, and to develop an understanding of the means by which these processes may be altered to reduce the temperature of growth and the utilization of toxic hydrides. The basic approach was to develop the required information about the chemical and physical kinetics operative in the gas phase and on the surface by the direct physical measurement of the processes whenever possible. The program included five tasks: (1) MOCVD growth process characterization, (2) photoenhanced MOCVD studies, (3) materials characterization, (4) device fabrication and characterization, and (5) photovoltaic training. Most of the goals of the program were met and significant progress was made in defining an approach that would allow both high throughput and high uniformity growth of compound semiconductors at low temperatures. The technical activity was focused on determining the rates of thermal decomposition of trimethyl gallium, exploring alternate arsenic sources for use MOCVD, and empirical studies of atomic layer epitaxy as an approach.

Dapkus, P.D. (University of Southern California, Los Angeles, CA (United States))

1993-02-01T23:59:59.000Z

99

Epitaxial Growth and Characterization of Silicon Carbide Films  

DOE Green Energy (OSTI)

Silicon carbide (SiC) epitaxial layers have been grown in a chemical vapor deposition (CVD) system designed and fabricated in our laboratory. Silicon tetrachloride-propane as well as silane-propane were used as precursor gases. The hot zone was designed based on simulation by using numerical modeling. Growth rates up to 200 {mu}m could be achieved. A new growth-assisted hydrogen etching was developed to show the distribution of the micropipes present in the substrate. Higher growth rate was observed on off-axis (0 0 0 1) 4 H SiC compared to the on-axis (0 0 0 1) wafer and growth mechanism was explained.

Dhanaraj,G.; Dudley, M.; Chen, Y.; Ragothamachar, B.; Wu, B.; Zhang, H.

2006-01-01T23:59:59.000Z

100

Chemical vapor deposition sciences  

SciTech Connect

Chemical vapor deposition (CVD) is a widely used method for depositing thin films of a variety of materials. Applications of CVD range from the fabrication of microelectronic devices to the deposition of protective coatings. New CVD processes are increasingly complex, with stringent requirements that make it more difficult to commercialize them in a timely fashion. However, a clear understanding of the fundamental science underlying a CVD process, as expressed through computer models, can substantially shorten the time required for reactor and process development. Research scientists at Sandia use a wide range of experimental and theoretical techniques for investigating the science of CVD. Experimental tools include optical probes for gas-phase and surface processes, a range of surface analytic techniques, molecular beam methods for gas/surface kinetics, flow visualization techniques and state-of-the-art crystal growth reactors. The theoretical strategy uses a structured approach to describe the coupled gas-phase and gas-surface chemistry, fluid dynamics, heat and mass transfer of a CVD process. The software used to describe chemical reaction mechanisms is easily adapted to codes that model a variety of reactor geometries. Carefully chosen experiments provide critical information on the chemical species, gas temperatures and flows that are necessary for model development and validation. This brochure provides basic information on Sandia`s capabilities in the physical and chemical sciences of CVD and related materials processing technologies. It contains a brief description of the major scientific and technical capabilities of the CVD staff and facilities, and a brief discussion of the approach that the staff uses to advance the scientific understanding of CVD processes.

1992-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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101

Thermal Stability and Substitutional Carbon Incorporation far above Solid-Solubility in Si1-xCx and Si1-x-yGexCy Layers Grown by Chemical Vapor Deposition  

E-Print Network (OSTI)

Cx and Si1-x-yGexCy Layers Grown by Chemical Vapor Deposition using Disilane M. S. Carroll*, J. C. Sturm on (100) silicon substrates by rapid thermal chemical vapor deposition (RTCVD) with disilane source gas and disilane is known to produce higher silicon epitaxial growth rates for similar partial

102

Vaporization of synthetic fuels. Final report. [Thesis  

DOE Green Energy (OSTI)

The problem of transient droplet vaporization in a hot convective environment is examined. The main objective of the present study is to develop an algorithm for the droplet vaporization which is simple enough to be feasibly incorporated into a complete spray combustion analysis and yet will also account for the important physics such as liquid-phase internal circulation, unsteady droplet heating and axisymmetric gas-phase convection. A simplified liquid-phase model has been obtained based on the assumption of the existence of a Hill's spherical vortex inside the droplet together with some approximations made in the governing diffusion equation. The use of the simplified model in a spray situation has also been examined. It has been found that droplet heating and vaporization are essentially unsteady and droplet temperature is nonuniform for a significant portion of its lifetime. It has also been found that the droplet vaporization characteristic can be quite sensitive to the particular liquid-phase and gas-phase models. The results of the various models are compared with the existing experimental data. Due to large scattering in the experimental measurements, particularly the droplet diameter, no definite conclusion can be drawn based on the experimental data. Finally, certain research problems which are related to the present study are suggested for future studies.

Sirignano, W.A.; Yao, S.C.; Tong, A.Y.; Talley, D.

1983-01-01T23:59:59.000Z

103

Epitaxial Growth and Properties of Cobalt-doped ZnO on ?-Al?O? Single-Crystal Substrates  

SciTech Connect

Co-doped ZnO (CoxZn?-xO) is of potential interest for spintronics due to the prediction of room-temperature ferromagnetism. We have grown epitaxial CoxZn?-xO films on Al?O?(012) substrates by metalorganic chemical vapor deposition using a liquid precursor delivery system. High concentrations of Co (x < 0.35) can be uniformly incorporated into the film without phase segregation. Co is found to be in the ?² oxidation state, independent of x. This material can be grown n type by the deliberate incorporation of oxygen vacancies, but not by inclusion of ~1 at. % Al. Semiconducting films remain ferromagnetic up to 350 K. In contrast films without oxygen vacancies are insulating and nonmagnetic, suggesting that exchange interaction is mediated by itinerant carriers. The saturation and remanent magnetization on a per Co basis was very small (< 0.1 ?B/Co), even in the best films. The dependence of saturation magnetization, as measured by optical magnetic circular dichroism, on magnetic field and temperature, agrees with the theoretical Brillouin function, demonstrating that the majority of the Co(II) ions behave as magnetically isolated S = 3/2 spins.

Tuan, Allan C.; Bryan, John D.; Pakhomov, Alexandre; Shutthanandan, V.; Thevuthasan, Suntharampillai; McCready, David E.; Gaspar, Dan J.; Engelhard, Mark H.; Rogers, J. W.; Krishnan, Kannan M.; Gamelin, Daniel R.; Chambers, Scott A.

2004-08-30T23:59:59.000Z

104

Tenth Biennial OMVPE Workshop--Hertz Rental Car - TMS  

Science Conference Proceedings (OSTI)

The Tenth Biennial Organometallic Vapor Phase Epitaxy Workshop (OMVPE), sponsored by the Electronic Materials Committee of The Minerals, Metals ...

105

Ninth Biennial OMVPE Workshop: Transportation and Travel ... - TMS  

Science Conference Proceedings (OSTI)

The Ninth Biennial Organometallic Vapor Phase Epitaxy Workshop (OMVPE), sponsored by the Electronic Materials Committee of The Minerals, Metals ...

106

Heat transfer during film condensation of potassium vapor  

E-Print Network (OSTI)

The object of this work is to investigate theoretically and experimentally the following two phases of heat transfer during condensation of potassium vapore, a. Heat transfer during film condensation of pure saturated ...

Kroger, Detlev Gustav

1966-01-01T23:59:59.000Z

107

Molecular beam epitaxy of SrTiO3 with a growth window  

E-Print Network (OSTI)

Materials Fundamentals of Molecular Beam Epitaxy (AcademicMolecular beam epitaxy of SrTiO 3 with a growth windowgrowth window in conventional molecular beam epitaxy (MBE)

Stemmer, Susanne

2009-01-01T23:59:59.000Z

108

Effects of capillarity and vapor adsorption in the depletion of vapor-dominated geothermal reservoirs  

DOE Green Energy (OSTI)

Vapor-dominated geothermal reservoirs in natural (undisturbed) conditions contain water as both vapor and liquid phases. The most compelling evidence for the presence of distributed liquid water is the observation that vapor pressures in these systems are close to saturated vapor pressure for measured reservoir temperatures (White et al., 1971; Truesdell and White, 1973). Analysis of natural heat flow conditions provides additional, indirect evidence for the ubiquitous presence of liquid. From an analysis of the heat pipe process (vapor-liquid counterflow) Preuss (1985) inferred that effective vertical permeability to liquid phase in vapor-dominated reservoirs is approximately 10{sup 17} m{sup 2}, for a heat flux of 1 W/m{sup 2}. This value appears to be at the high end of matrix permeabilities of unfractured rocks at The Geysers, suggesting that at least the smaller fractures contribute to liquid permeability. For liquid to be mobile in fractures, the rock matrix must be essentially completely liquid-saturated, because otherwise liquid phase would be sucked from the fractures into the matrix by capillary force. Large water saturation in the matrix, well above the irreducible saturation of perhaps 30%, has been shown to be compatible with production of superheated steam (Pruess and Narasimhan, 1982). In response to fluid production the liquid phase will boil, with heat of vaporization supplied by the reservoir rocks. As reservoir temperatures decline reservoir pressures will decline also. For depletion of ''bulk'' liquid, the pressure would decline along the saturated vapor pressure curve, while for liquid held by capillary and adsorptive forces inside porous media, an additional decline will arise from ''vapor pressure lowering''. Capillary pressure and vapor adsorption effects, and associated vapor pressure lowering phenomena, have received considerable attention in the geothermal literature, and also in studies related to geologic disposal of heat generating nuclear wastes, and in the drying of porous materials. Geothermally oriented studies were presented by Chicoine et al. (1977), Hsieh and Ramey (1978, 1981), Herkelrath et al. (1983), and Nghiem and Ramey (1991). Nuclear waste-related work includes papers by Herkelrath and O'Neal (1985), Pollock (1986), Eaton and Bixler (1987), Pruess et al. (1990), Nitao (1990), and Doughty and E'ruess (1991). Applications to industrial drying of porous materials have been discussed by Hamiathy (1969) arid Whitaker (1977). This paper is primarily concerned with evaluating the impact of vapor pressure lowering (VPL) effects on the depletion behavior of vapor-dominated reservoirs. We have examined experimental data on vapor adsorption and capillary pressures in an effort to identify constitutive relationships that would be applicable to the tight matrix rocks of vapor-dominated systems. Numerical simulations have been performed to evaluate the impact of these effects on the depletion of vapor-dominated reservoirs.

Pruess, Karsten; O'Sullivan, Michael

1992-01-01T23:59:59.000Z

109

Process for forming epitaxial perovskite thin film layers using halide precursors  

DOE Patents (OSTI)

A process for forming an epitaxial perovskite-phase thin film on a substrate. This thin film can act as a buffer layer between a Ni substrate and a YBa.sub.2 Cu.sub.3 O.sub.7-x superconductor layer. The process utilizes alkali or alkaline metal acetates dissolved in halogenated organic acid along with titanium isopropoxide to dip or spin-coat the substrate which is then heated to about 700.degree. C. in an inert gas atmosphere to form the epitaxial film on the substrate. The YBCO superconductor can then be deposited on the layer formed by this invention.

Clem, Paul G. (Albuquerque, NM); Rodriguez, Mark A. (Albuquerque, NM); Voigt, James A. (Corrales, NM); Ashley, Carol S. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

110

Electrolyte vapor condenser  

DOE Patents (OSTI)

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well. 3 figs.

Sederquist, R.A.; Szydlowski, D.F.; Sawyer, R.D.

1983-02-08T23:59:59.000Z

111

Electrolyte vapor condenser  

DOE Patents (OSTI)

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well.

Sederquist, Richard A. (Newington, CT); Szydlowski, Donald F. (East Hartford, CT); Sawyer, Richard D. (Canton, CT)

1983-01-01T23:59:59.000Z

112

Vapor concentration monitor  

DOE Patents (OSTI)

An apparatus for monitoring the concentration of a vapor, such as heavy water, having at least one narrow bandwidth in its absorption spectrum, in a sample gas such as air. The air is drawn into a chamber in which the vapor content is measured by means of its radiation absorption spectrum. High sensitivity is obtained by modulating the wavelength at a relatively high frequency without changing its optical path, while high stability against zero drift is obtained by the low frequency interchange of the sample gas to be monitored and of a reference sample. The variable HDO background due to natural humidity is automatically corrected.

Bayly, John G. (Deep River, CA); Booth, Ronald J. (Deep River, CA)

1977-01-01T23:59:59.000Z

113

Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from Ethanol/Gasoline Fuels; Phase 3: Effects of Winter Gasoline Volatility and Ethanol Content on Blend Flammability; Flammability Limits of Denatured Ethanol  

DOE Green Energy (OSTI)

This study assessed differences in headspace flammability for summertime gasolines and new high-ethanol content fuel blends. The results apply to vehicle fuel tanks and underground storage tanks. Ambient temperature and fuel formulation effects on headspace vapor flammability of ethanol/gasoline blends were evaluated. Depending on the degree of tank filling, fuel type, and ambient temperature, fuel vapors in a tank can be flammable or non-flammable. Pure gasoline vapors in tanks generally are too rich to be flammable unless ambient temperatures are extremely low. High percentages of ethanol blended with gasoline can be less volatile than pure gasoline and can produce flammable headspace vapors at common ambient temperatures. The study supports refinements of fuel ethanol volatility specifications and shows potential consequences of using noncompliant fuels. E85 is flammable at low temperatures; denatured ethanol is flammable at warmer temperatures. If both are stored at the same location, one or both of the tanks' headspace vapors will be flammable over a wide range of ambient temperatures. This is relevant to allowing consumers to splash -blend ethanol and gasoline at fueling stations. Fuels compliant with ASTM volatility specifications are relatively safe, but the E85 samples tested indicate that some ethanol fuels may produce flammable vapors.

Gardiner, D. P.; Bardon, M. F.; Clark, W.

2011-07-01T23:59:59.000Z

114

Definition: Mercury Vapor | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor Jump to: navigation, search Dictionary.png Mercury Vapor Mercury is discharged as a highly volatile vapor during hydrothermal activity and high concentrations in...

115

Organic vapor jet printing system  

DOE Patents (OSTI)

An organic vapor jet printing system includes a pump for increasing the pressure of an organic flux.

Forrest, Stephen R

2012-10-23T23:59:59.000Z

116

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Wednesday, 26 March 2008 00:00 Prospective challengers to...

117

Mercury Vapor | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor Mercury Vapor Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Mercury Vapor Details Activities (23) Areas (23) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Fluid Lab Analysis Parent Exploration Technique: Fluid Lab Analysis Information Provided by Technique Lithology: Stratigraphic/Structural: Anomalously high concentrations can indicate high permeability or conduit for fluid flow Hydrological: Field wide soil sampling can generate a geometrical approximation of fluid circulation Thermal: High concentration in soils can be indicative of active hydrothermal activity Dictionary.png Mercury Vapor: Mercury is discharged as a highly volatile vapor during hydrothermal

118

Stratified vapor generator  

DOE Patents (OSTI)

A stratified vapor generator (110) comprises a first heating section (H.sub.1) and a second heating section (H.sub.2). The first and second heating sections (H.sub.1, H.sub.2) are arranged so that the inlet of the second heating section (H.sub.2) is operatively associated with the outlet of the first heating section (H.sub.1). A moisture separator (126) having a vapor outlet (164) and a liquid outlet (144) is operatively associated with the outlet (124) of the second heating section (H.sub.2). A cooling section (C.sub.1) is operatively associated with the liquid outlet (144) of the moisture separator (126) and includes an outlet that is operatively associated with the inlet of the second heating section (H.sub.2).

Bharathan, Desikan (Lakewood, CO); Hassani, Vahab (Golden, CO)

2008-05-20T23:59:59.000Z

119

Fuel vapor canister  

SciTech Connect

This paper discusses an improved fuel vapor storage canister for use in a vehicle emission system of the type utilizing an enclosure with an interior communicated with a source of fuel vapor. The improved canister comprises: the enclosure having a mixture including particles of activated charcoal and many pieces of foam rubber, the pieces of foam rubber in the mixture being randomly and substantially evenly dispersed whereby substantially all the charcoal particles are spaced relatively closely to at least one foam rubber piece; the mixture being packed into the enclosure under pressure so that the pieces of foam rubber are compressed enough to tightly secure the charcoal particles one against another to prevent a griding action therebetween.

Moskaitis, R.J.; Ciuffetelli, L.A.

1991-03-26T23:59:59.000Z

120

VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS  

DOE Green Energy (OSTI)

This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization which have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.

Eric M. Suuberg; Vahur Oja

1997-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Electrostatic transfer of epitaxial graphene to glass.  

SciTech Connect

We report on a scalable electrostatic process to transfer epitaxial graphene to arbitrary glass substrates, including Pyrex and Zerodur. This transfer process could enable wafer-level integration of graphene with structured and electronically-active substrates such as MEMS and CMOS. We will describe the electrostatic transfer method and will compare the properties of the transferred graphene with nominally-equivalent 'as-grown' epitaxial graphene on SiC. The electronic properties of the graphene will be measured using magnetoresistive, four-probe, and graphene field effect transistor geometries [1]. To begin, high-quality epitaxial graphene (mobility 14,000 cm2/Vs and domains >100 {micro}m2) is grown on SiC in an argon-mediated environment [2,3]. The electrostatic transfer then takes place through the application of a large electric field between the donor graphene sample (anode) and the heated acceptor glass substrate (cathode). Using this electrostatic technique, both patterned few-layer graphene from SiC(000-1) and chip-scale monolayer graphene from SiC(0001) are transferred to Pyrex and Zerodur substrates. Subsequent examination of the transferred graphene by Raman spectroscopy confirms that the graphene can be transferred without inducing defects. Furthermore, the strain inherent in epitaxial graphene on SiC(0001) is found to be partially relaxed after the transfer to the glass substrates.

Ohta, Taisuke; Pan, Wei; Howell, Stephen Wayne; Biedermann, Laura Butler; Beechem Iii, Thomas Edwin; Ross, Anthony Joseph, III

2010-12-01T23:59:59.000Z

122

New High Performance Water Vapor Membranes to Improve Fuel Cell Balance of Plant Efficiency and Lower Costs (SBIR Phase I) - DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report  

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

0 0 DOE Hydrogen and Fuel Cells Program FY 2012 Annual Progress Report Earl H. Wagener (Primary Contact), Brad P. Morgan, Jeffrey R. DiMaio Tetramer Technologies L.L.C. 657 S. Mechanic St. Pendleton, SC 29670 Phone: (864) 646-6282 Email: earl.wagener@tetramertechnologies.com DOE Manager HQ: Nancy Garland Phone: (202) 586-5673 Email: Nancy.Garland@ee.doe.gov Contract Number: DE-SC0006172 Project Start Date: June 17, 2011 Project End Date: March 16, 2012 Fiscal Year (FY) 2012 Objectives Demonstrate water vapor transport membrane with * >18,000 gas permeation units (GPU) Water vapor membrane with less than 20% loss in * performance after stress tests Crossover leak rate: <150 GPU * Temperature Durability of 90°C with excursions to * 100°C Cost of <$10/m

123

Vapor spill pipe monitor  

DOE Patents (OSTI)

The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

Bianchini, G.M.; McRae, T.G.

1983-06-23T23:59:59.000Z

124

Low temperature metal-organic chemical vapor deposition growth processes for high-efficiency solar cells. Final technical report, 1 September 1985--30 November 1989  

DOE Green Energy (OSTI)

This report describes the results of a program to develop a more complete understanding of the physical and chemical processes involved in low-temperature growth of III-V compounds by metal-organic chemical vapor deposition (MOCVD) and to develop a low-temperature process that is suitable for the growth of high-efficiency solar cells. The program was structured to develop a better understanding of the chemical reactions involved in MOCVD growth, to develop a model of the processes occurring in the gas phase, to understand the physical kinetics and reactions operative on the surface of the growing crystal, and to develop an understanding of the means by which these processes may be altered to reduce the temperature of growth and the utilization of toxic hydrides. The basic approach was to develop the required information about the chemical and physical kinetics operative in the gas phase and on the surface by the direct physical measurement of the processes whenever possible. The program included five tasks: (1) MOCVD growth process characterization, (2) photoenhanced MOCVD studies, (3) materials characterization, (4) device fabrication and characterization, and (5) photovoltaic training. Most of the goals of the program were met and significant progress was made in defining an approach that would allow both high throughput and high uniformity growth of compound semiconductors at low temperatures. The technical activity was focused on determining the rates of thermal decomposition of trimethyl gallium, exploring alternate arsenic sources for use MOCVD, and empirical studies of atomic layer epitaxy as an approach.

Dapkus, P.D. [University of Southern California, Los Angeles, CA (United States)

1993-02-01T23:59:59.000Z

125

Interfacial instability induced by lateral vapor pressure fluctuation in bounded thin liquid-vapor layers  

E-Print Network (OSTI)

We study an instability of thin liquid-vapor layers bounded by rigid parallel walls from both below and above. In this system, the interfacial instability is induced by lateral vapor pressure fluctuation, which is in turn attributed to the effect of phase change: evaporation occurs at the hotter portion of the interface and condensation at the colder one. The high vapor pressure drives the liquid away and the low one pulls it up. A set of equations describing the temporal evolution of the interface of the liquid-vapor layers is derived. This model neglects the effect of mass loss or gain at the interface and guarantees the mass conservation of the liquid layer. The result of linear stability analysis of the model shows that the presence of the pressure dependence of the local saturation temperature suppresses the growth of long-wave disturbances. We find the stability criterion, which suggests that only slight temperature gradients are sufficient to overcome the stabilizing gravitational effect for a water an...

Kanatani, Kentaro

2008-01-01T23:59:59.000Z

126

SILICON-BASED EPITAXY BY CHEMICAL VAPOR DEPOSITION USING NOVEL PRECURSOR  

E-Print Network (OSTI)

.e. from silane to disilane to trisilane) the silicon growth rate increases for the same experimental

127

Chemical Vapor Deposition Epitaxy of Silicon-based Materials using Neopentasilane  

E-Print Network (OSTI)

of dichlorosilane, silane, disilane, and neopentasilane vs. inverse temperature observed in our lab on Si(100 dichlorosilane is not observable, and that for silane and disilane were 0.6 and 8 ECS Transactions, 16 (10) 799 sources of dichlorosilane (DCS), silane, disilane and neopentasilane (NPS) precursor on (100) silicon

128

Method of deposition by molecular beam epitaxy  

DOE Patents (OSTI)

A method is described for reproducibly controlling layer thickness and varying layer composition in an MBE deposition process. In particular, the present invention includes epitaxially depositing a plurality of layers of material on a substrate with a plurality of growth cycles whereby the average of the instantaneous growth rates for each growth cycle and from one growth cycle to the next remains substantially constant as a function of time.

Chalmers, Scott A. (Albuquerque, NM); Killeen, Kevin P. (Albuquerque, NM); Lear, Kevin L. (Albuquerque, NM)

1995-01-01T23:59:59.000Z

129

Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells: Preprint  

Science Conference Proceedings (OSTI)

We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n++ Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

2011-07-01T23:59:59.000Z

130

Photoluminescence study of GaAs films on Si(100) grown by atomic hydrogen-assisted molecular beam epitaxy  

Science Conference Proceedings (OSTI)

Keywords: atomic hydrogen-mediated epitaxy, lattice-mismatched heteroepitaxy, minority carrier lifetime, molecular beam epitaxy, photoluminescence decay, solar cells

Yoshitaka Okada; Shigeru Ohta; Akio Kawabata; Hirofumi Shimomura; Mitsuo Kawabe

1994-03-01T23:59:59.000Z

131

Selective epitaxy using the GILD process  

DOE Patents (OSTI)

The present invention comprises a method of selective epitaxy on a semiconductor substrate. The present invention provides a method of selectively forming high quality, thin GeSi layers in a silicon circuit, and a method for fabricating smaller semiconductor chips with a greater yield (more error free chips) at a lower cost. The method comprises forming an upper layer over a substrate, and depositing a reflectivity mask which is then removed over selected sections. Using a laser to melt the unmasked sections of the upper layer, the semiconductor material in the upper layer is heated and diffused into the substrate semiconductor material. By varying the amount of laser radiation, the epitaxial layer is formed to a controlled depth which may be very thin. When cooled, a single crystal epitaxial layer is formed over the patterned substrate. The present invention provides the ability to selectively grow layers of mixed semiconductors over patterned substrates such as a layer of Ge{sub x}Si{sub 1-x} grown over silicon. Such a process may be used to manufacture small transistors that have a narrow base, heavy doping, and high gain. The narrowness allows a faster transistor, and the heavy doping reduces the resistance of the narrow layer. The process does not require high temperature annealing; therefore materials such as aluminum can be used. Furthermore, the process may be used to fabricate diodes that have a high reverse breakdown voltage and a low reverse leakage current.

Weiner, K.H.

1990-12-31T23:59:59.000Z

132

Epitaxial europium oxide on Ni(100) with single-crystal quality  

SciTech Connect

High quality epitaxy of EuO on Ni(100) is developed in an in situ scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED) study. A careful selection of the initial growth parameters is decisive to obtain a surface oxide suitable for the subsequent epitaxy of single phase EuO(100). After the creation of a three layer thick coalesced oxide film for the subsequent growth a distillation technique is applied. Appropriate annealing of films with up to 100 nm thickness generates sufficient conductivity for STM and electron spectroscopies. Oxygen vacancies are directly imaged by STM. They are of decisive importance for the metal-to-insulator transition around the temperature of the ferromagnetic-to-paramagnetic transition. A fast relaxation of the initial biaxial strain observed by LEED leaves little hope for an increase of the Curie temperature through epitaxial compression. Ex situ x-ray adsorption spectroscopy and magneto-optical Kerr effect microscopy measurements of thicker films are consistent with the stoichiometric single phase EuO with bulk properties.

Foerster, Daniel F.; Klinkhammer, Juergen; Busse, Carsten; Altendorf, Simone G.; Michely, Thomas; Hu Zhiwei; Chin Yiying; Tjeng, L. H.; Coraux, Johann; Bourgault, Daniel [II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Strasse 77, D-50937 Koeln (Germany); II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Strasse 77, D-50937 Koeln, Germany and Max Planck Institute for Chemical Physics of Solids, Noethnitzerstr. 40, D-01187 Dresden (Germany); Institut Neel, CNRS-UJF, 25 rue des Martyrs, F-38042 Grenoble Cedex 9 (France)

2011-01-15T23:59:59.000Z

133

Phase separated, self-assembled, vertically aligned epitaxial ...  

window/absorber materials with well-understood, customized and predesigned properties will ultimately lead to PV devices with increased overall cell efficiency, ...

134

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Prospective challengers to silicon, the long-reigning king of semiconductors for computer chips and other electronic...

135

VAPOR SHIELD FOR INDUCTION FURNACE  

DOE Patents (OSTI)

This patent relates to a water-cooled vapor shield for an inductlon furnace that will condense metallic vapors arising from the crucible and thus prevent their condensation on or near the induction coils, thereby eliminating possible corrosion or shorting out of the coils. This is accomplished by placing, about the top, of the crucible a disk, apron, and cooling jacket that separates the area of the coils from the interior of the cruclbIe and provides a cooled surface upon whlch the vapors may condense.

Reese, S.L.; Samoriga, S.A.

1958-03-11T23:59:59.000Z

136

Method of physical vapor deposition of metal oxides on semiconductors  

DOE Patents (OSTI)

A process for growing a metal oxide thin film upon a semiconductor surface with a physical vapor deposition technique in a high-vacuum environment and a structure formed with the process involves the steps of heating the semiconductor surface and introducing hydrogen gas into the high-vacuum environment to develop conditions at the semiconductor surface which are favorable for growing the desired metal oxide upon the semiconductor surface yet is unfavorable for the formation of any native oxides upon the semiconductor. More specifically, the temperature of the semiconductor surface and the ratio of hydrogen partial pressure to water pressure within the vacuum environment are high enough to render the formation of native oxides on the semiconductor surface thermodynamically unstable yet are not so high that the formation of the desired metal oxide on the semiconductor surface is thermodynamically unstable. Having established these conditions, constituent atoms of the metal oxide to be deposited upon the semiconductor surface are directed toward the surface of the semiconductor by a physical vapor deposition technique so that the atoms come to rest upon the semiconductor surface as a thin film of metal oxide with no native oxide at the semiconductor surface/thin film interface. An example of a structure formed by this method includes an epitaxial thin film of (001)-oriented CeO.sub.2 overlying a substrate of (001) Ge.

Norton, David P. (Knoxville, TN)

2001-01-01T23:59:59.000Z

137

Vapor-Liquid Partitioning of Sulfuric Acid and Ammonium Sulfate  

Science Conference Proceedings (OSTI)

The quality of water and steam is central to ensuring power plant component availability and reliability. A key part of developing operating cycle chemistry guidelines is an understanding of the impurity distribution between water and steam. This study focused on the partitioning of sulfuric acid and ammonium bisulfate between the liquid and vapor phases.

1999-03-31T23:59:59.000Z

138

Vapor adsorption process  

SciTech Connect

The removal of undesirable acid components from sour natural gas is often accomplished by a vapor adsorption process wherein a bed of solid adsorbent material is contacted with an inlet gas stream so that desired components contained in the gas stream are adsorbed on the bed, then regenerated by contact with a heated regeneration gas stream. Adsorbed components are desorbed from the bed and the bed is cooled preparatory to again being contacted with the inlet gas stream. By this process, the bed is contacted, during the regeneration cycle, with a selected adsorbable material. This material has the property of being displaced from the bed by the desired components and has a heat of desorption equal to or greater than the heat of adsorption of the desired components. When the bed is contacted with the inlet gas stream, the selected adsorbable material is displaced by the desired components resulting in the temperature of the bed remaining relatively constant, thereby allowing the utilization of the maximum bed adsorption capacity. (4 claims)

Snyder, C.F.; Casad, B.M.

1973-04-24T23:59:59.000Z

139

Epitaxial Crystal Silicon Absorber Layers and Solar Cells Grown at 1.8 Microns per Minute: Preprint  

DOE Green Energy (OSTI)

We have grown device-quality epitaxial silicon thin films at growth rates up to 1.8 ?m/min, using hot-wire chemical vapor deposition from silane at substrate temperatures below 750 degrees C. At these rates, which are more than 30 times faster than those used by the amorphous and nanocrystalline Si industry, capital costs for large-scale solar cell production would be dramatically reduced, even for cell absorber layers up to 10 ?m thick. We achieved high growth rates by optimizing the three key parameters: silane flow, depletion, and filament geometry, based on our model developed earlier. Hydrogen coverage of the filament surface likely limits silane decomposition and growth rate at high system pressures. No considerable deterioration in PV device performance is observed when grown at high rate, provided that the epitaxial growth is initiated at low rate. A simple mesa device structure (wafer/epi Si/a-Si(i)/a-Si:H(p)/ITO) with a 2.3 um epitaxial silicon absorber layer was grown at 700 nm/min. The finished device had an open-circuit voltage of 0.424 V without hydrogenation treatment.

Bobela, D. C.; Teplin, C. W.; Young, D. L.; Branz, H. M.; Stradins, P.

2011-07-01T23:59:59.000Z

140

Atmospheric Water Vapor over China  

Science Conference Proceedings (OSTI)

Chinese radiosonde data from 1970 to 1990 are relatively homogeneous in time and are used to examine the climatology, trends, and variability of China’s atmospheric water vapor content. The climatological distribution of precipitable water (PW) ...

Panmao Zhai; Robert E. Eskridge

1997-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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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141

Vapor deposition of hardened niobium  

DOE Patents (OSTI)

A method of coating ceramic nuclear fuel particles containing a major amount of an actinide ceramic in which the particles are placed in a fluidized bed maintained at ca. 800.degree. to ca. 900.degree. C., and niobium pentachloride vapor and carbon tetrachloride vapor are led into the bed, whereby niobium metal is deposited on the particles and carbon is deposited interstitially within the niobium. Coating apparatus used in the method is also disclosed.

Blocher, Jr., John M. (Columbus, OH); Veigel, Neil D. (Columbus, OH); Landrigan, Richard B. (Columbus, OH)

1983-04-19T23:59:59.000Z

142

New plasma source of hydrides for epitaxial growth. Final subcontract report, 15 April 1991--3 September 1993  

DOE Green Energy (OSTI)

This report describes a novel plasma-activated selenium source that was developed during the course of this subcontract and which is significantly different than any other heretofore reported in the scientific literature. It involves microwave excited, magnetically confined plasma sources that are intended to operate under electron cyclotron resonance (ECR) conditions at 2.455 GHz. This source is designed to excite and dissociate the molecular vapor evaporating or subliming from a heated solid or liquid reservoir. It can combine an effusion cell vapor flux with a stream of hydrogen or helium gas, enabling the in-situ generation of hydrides for use in low-pressure growth techniques where long mean free paths are desirable. Experiments were conducted to demonstrate a stable discharge within the source, and measures were identified to improve its operational characteristics. Application of this novel source is anticipated to enable a low-temperature, safe process for the growth of high-quality epitaxial compound semiconductor films. This reduction of epitaxial growth temperatures may enable the fabrication of novel photovoltaic devices that have heretofore been impossible due to the deleterious effects of interdiffusion at heterointerfaces resulting from the high temperatures required to grow adequate quality material using conventional processes.

Stanbery, B.J. [Boeing Defense & Space Group, Seattle, WA (United States)

1994-05-01T23:59:59.000Z

143

Integration of low dimensional crystalline Si into functional epitaxial oxides  

Science Conference Proceedings (OSTI)

In this work we show that by efficiently exploiting the growth kinetics during molecular beam epitaxy (MBE) one could create Si nanostructures of different dimensions. Examples are Si quantum dots (QD) or quantum wells (QW), which are buried into an ... Keywords: Epitaxial gadolinium oxide, Nonvolatile memories, Oxide-semiconductor-oxide quantum well, Resonant tunneling diode, Si quantum dots

Apurba Laha; E. Bugiel; R. Dargis; D. Schwendt; M. Badylevich; V. V. Afanas'ev; A. Stesmans; A. Fissel; H. J. Osten

2009-03-01T23:59:59.000Z

144

Processing of CuInSe{sub 2}-based solar cells: Characterization of deposition processes in terms of chemical reaction analyses. Phase 2 Annual Report, 6 May 1996--5 May 1997  

DOE Green Energy (OSTI)

This report describes research performed by the University of Florida during Phase 2 of this subcontract. First, to study CIGS, researchers adapted a contactless, nondestructive technique previously developed for measuring photogenerated excess carrier lifetimes in SOI wafers. This dual-beam optical modulation (DBOM) technique was used to investigate the differences between three alternative methods of depositing CdS (conventional chemical-bath deposition [CBD], metal-organic chemical vapor deposition [MOCVD], and sputtering). Second, a critical assessment of the Cu-In-Se thermochemical and phase diagram data using standard CALPHAD procedures is being performed. The outcome of this research will produce useful information on equilibrium vapor compositions (required annealing ambients, Sex fluxes from effusion cells), phase diagrams (conditions for melt-assisted growth), chemical potentials (driving forces for diffusion and chemical reactions), and consistent solution models (extents of solid solutions and extending phase diagrams). Third, an integrated facility to fabricate CIS PV devices was established that includes migration-enhanced epitaxy (MEE) for deposition of CIS, a rapid thermal processing furnace for absorber film formation, sputtering of ZnO, CBD or MOCVD of CdS, metallization, and pattern definition.

Anderson, T.

1999-10-20T23:59:59.000Z

145

Epitaxial silicon growth for solar cells. Final report  

DOE Green Energy (OSTI)

The objectives of this contract were: (1) to determine the feasibility of silicon epitaxial growth on low-cost silicon substrates for the development of silicon sheet capable of producing low-cost, high efficiency solar cells; (2) to achieve a goal of 12% (AM-0) efficient solar cells fabricated on thin epitaxial layers (<25 ..mu..m) grown on low-cost substrates; and (3) to evaluate the add-on cost for the epitaxial process and to develop low-cost epitaxial growth procedures for application in conjunction with low-cost silicon substrates. The basic epitaxial procedures and solar-cell fabrication and evaluation techniques are described, followed by a discussion of the development of baseline epitaxial solar-cell structures, grown on high-quality conventional silicon substrates. This work resulted in the definition of three basic structures which reproducibly yielded efficiencies in the range of 12 to 13.7%. These epitaxial growth procedures and baseline structures were then used to grow diagnostic layers and solar cells on four potentially low-cost silicon substrates. A description of the crystallographic properties of such layers and the performance of epitaxially grown solar cells fabricated on these materials is given. The major results were the achievement of cell efficiencies of 10.6 to 11.2% on multigrained substrates and approx. 13% on a low-cost single-crystal substrate. An advanced epitaxial reactor, the Rotary Disc, is described. The results of growing solar-cell structures of the baseline type and on low-cost substrates are given. The add-on cost for the epitaxial process is assessed. These cost estimates show a value of approx. 0.46/W using existing or near-term technologies and project an add-on cost of $0.10/W for future reactors.

D'Aiello, R.V.; Robinson, P.H.; Richman, D.

1979-04-01T23:59:59.000Z

146

Development of Production PVD-AIN Buffer Layer System and Processes to Reduce Epitaxy Costs and Increase LED Efficiency  

SciTech Connect

The DOE has set aggressive goals for solid state lighting (SSL) adoption, which require manufacturing and quality improvements for virtually all process steps leading to an LED luminaire product. The goals pertinent to this proposed project are to reduce the cost and improve the quality of the epitaxial growth processes used to build LED structures. The objectives outlined in this proposal focus on achieving cost reduction and performance improvements over state-of-the-art, using technologies that are low in cost and amenable to high efficiency manufacturing. The objectives of the outlined proposal focus on cost reductions in epitaxial growth by reducing epitaxy layer thickness and hetero-epitaxial strain, and by enabling the use of larger, less expensive silicon substrates and would be accomplished through the introduction of a high productivity reactive sputtering system and an effective sputtered aluminum-nitride (AlN) buffer/nucleation layer process. Success of the proposed project could enable efficient adoption of GaN on-silicon (GaN/Si) epitaxial technology on 150mm silicon substrates. The reduction in epitaxy cost per cm{sup 2} using 150mm GaN-on-Si technology derives from (1) a reduction in cost of ownership and increase in throughput for the buffer deposition process via the elimination of MOCVD buffer layers and other throughput and CoO enhancements, (2) improvement in brightness through reductions in defect density, (3) reduction in substrate cost through the replacement of sapphire with silicon, and (4) reduction in non-ESD yield loss through reductions in wafer bow and temperature variation. The adoption of 150mm GaN/Si processing will also facilitate significant cost reductions in subsequent wafer fabrication manufacturing costs. There were three phases to this project. These three phases overlap in order to aggressively facilitate a commercially available production GaN/Si capability. In Phase I of the project, the repeatability of the performance was analyzed and improvements implemented to the Veeco PVD-AlN prototype system to establish a specification and baseline PVD-AlN films on sapphire and in parallel the evaluation of PVD AlN on silicon substrates began. In Phase II of the project a Beta tool based on a scaled-up process module capable of depositing uniform films on batches of 4”or 6” diameter substrates in a production worthy operation was developed and qualified. In Phase III, the means to increase the throughput of the PVD-AlN system was evaluated and focused primarily on minimizing the impact of the substrate heating and cooling times that dominated the overall cycle time.

Cerio, Frank

2013-09-14T23:59:59.000Z

147

Growth temperature dependence of epitaxial Gd2O3 films on Si(111)  

Science Conference Proceedings (OSTI)

This article reports on the epitaxy of crystalline high @k oxide Gd"2O"3 layers on Si(111) for CMOS gate application. Epitaxial Gd"2O"3 thin films have been grown by Molecular Beam Epitaxy (MBE) on Si(111) substrates between 650 and 750^oC. The structural ... Keywords: Crystalline high ? oxide, Electrical properties, Gd2O3, Molecular beam epitaxy

G. Niu; B. Vilquin; N. Baboux; C. Plossu; L. Becerra; G. Saint-Grions; G. Hollinger

2009-07-01T23:59:59.000Z

148

van der Waals Epitaxy of MoS2 Layers Using Graphene As Growth Templates  

SciTech Connect

We present a method for synthesizing MoS{sub 2}/Graphene hybrid heterostructures with a growth template of graphene-covered Cu foil. Compared to other recent reports, a much lower growth temperature of 400 C is required for this procedure. The chemical vapor deposition of MoS{sub 2} on the graphene surface gives rise to single crystalline hexagonal flakes with a typical lateral size ranging from several hundred nanometers to several micrometers. The precursor (ammonium thiomolybdate) together with solvent was transported to graphene surface by a carrier gas at room temperature, which was then followed by post annealing. At an elevated temperature, the precursor self-assembles to form MoS{sub 2} flakes epitaxially on the graphene surface via thermal decomposition. With higher amount of precursor delivered onto the graphene surface, a continuous MoS{sub 2} film on graphene can be obtained. This simple chemical vapor deposition method provides a unique approach for the synthesis of graphene heterostructures and surface functionalization of graphene. The synthesized two-dimensional MoS{sub 2}/Graphene hybrids possess great potential toward the development of new optical and electronic devices as well as a wide variety of newly synthesizable compounds for catalysts.

Shi, Yumeng [Massachusetts Institute of Technology (MIT); Zhou, Wu [Vanderbilt University; Lu, Ang-Yu [Academia Sinica, Hefei, China; Fang, Wenjing [Massachusetts Institute of Technology (MIT); Lee, Yi-Hsien [Massachusetts Institute of Technology (MIT); Hsu, Allen Long [Massachusetts Institute of Technology (MIT); Kim, Soo Min [Massachusetts Institute of Technology (MIT); Kim, Ki Kang [Massachusetts Institute of Technology (MIT); Yang, Hui Ying [Singapore University of Technology and Design; Liang, Lain-Jong [Academia Sinica, Hefei, China; Idrobo Tapia, Juan C [ORNL; Kong, Jing [Massachusetts Institute of Technology (MIT)

2012-01-01T23:59:59.000Z

149

Ethanol production by vapor compression distillation  

DOE Green Energy (OSTI)

The goal of this project is to develop and demonstrate a one gallon per hour vapor compression distillation unit for fuel ethanol production that can be profitably manufactured and economically operated by individual family units. Vapor compression distillation is already an industrially accepted process and this project's goal is to demonstrate that it can be done economically on a small scale. Theoretically, the process is independent of absolute pressure. It is only necessary that the condenser be at higher pressure than the evaporator. By reducing the entire process to a pressure of approximately 0.1 atmosphere, the evaporation and condensation can occur at near ambient temperature. Even though this approach requires a vacuum pump, and thus will not represent the final cost effective design, it does not require preheaters, high temperature materials, or as much insulation as if it were to operate a near ambient pressure. Therefore, the operation of the ambient temperature unit constitutes the first phase of this project. Presently, the ambient temperature unit is fully assembled and has begun testing. So far it has successfully separated ethanol from a nine to one diluted input solution. However the production rate has been very low.

Ellis, G.S.

1981-01-01T23:59:59.000Z

150

Epitaxial oxygen sponges as low temperature catalysts | ornl.gov  

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

Functional Materials for Energy Functional Materials for Energy Epitaxial oxygen sponges as low temperature catalysts September 10, 2013 Crystal structure of SrCoO2.5 superimposed on a scanning transmission electron microscopy image of an epitaxially stabilized oxygen sponge. Fast and reversible redox reactions at considerably reduced temperatures are achieved by epitaxial stabilization of multivalent transition metal oxides. This illustrates the unprecedented potential of complex oxides for oxide-ionics, where oxidation state changes are used for energy generation, storage and electrochemical sensing. Thermomechanical degradation reduces the overall performance and lifetime of many perovskite oxides undergoing reversible redox reactions, such as those found in solid oxide fuel cells, rechargeable batteries,

151

Epitaxial EuO thin films on GaAs  

SciTech Connect

We demonstrate the epitaxial growth of EuO on GaAs by reactive molecular beam epitaxy. Thin films are grown in an adsorption-controlled regime with the aid of an MgO diffusion barrier. Despite the large lattice mismatch, it is shown that EuO grows well on MgO(001) with excellent magnetic properties. Epitaxy on GaAs is cube-on-cube and longitudinal magneto-optic Kerr effect measurements demonstrate a large Kerr rotation of 0.57 deg., a significant remanent magnetization, and a Curie temperature of 69 K.

Swartz, A. G.; Ciraldo, J.; Wong, J. J. I.; Li Yan; Han Wei; Lin Tao; Shi, J.; Kawakami, R. K. [Department of Physics and Astronomy, University of California, Riverside, California 92521 (United States); Mack, S.; Awschalom, D. D. [Center for Spintronics and Quantum Computation, University of California, Santa Barbara, California 93106 (United States)

2010-09-13T23:59:59.000Z

152

How solvent vapors can improve steam floods  

Science Conference Proceedings (OSTI)

Thermal recovery methods depend for their success on the viscosity reduction of heavy crude oils at high temperatures. The viscosity of a heavy oil can also be reduced if it is diluted with a low-viscosity solvent, such as one of the lighter hydrocarbons. It is not surprising that there has been considerable interest in combining the two methods. The process of injecting vaporized solvent with the steam for a gravity drainage type recovery is described here along with a description of the particular phase behavior of steam/solvent mixtures which is beneficial to the process. And computer simulations which compare steam-only and steam/solvent floods under Athabasca-type conditions are overviewed.

Vogel, J. [Vogel, (Jack), Seabrook, TX (United States)

1996-11-01T23:59:59.000Z

153

Atomic vapor laser isotope separation process  

DOE Patents (OSTI)

A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

Wyeth, R.W.; Paisner, J.A.; Story, T.

1990-08-21T23:59:59.000Z

154

Distribution of Tropical Tropospheric Water Vapor  

Science Conference Proceedings (OSTI)

Utilizing a conceptual model for tropical convection and observational data for water vapor, the maintenance of the vertical distribution of the tropical tropospheric water vapor is discussed. While deep convection induces large-scale subsidence ...

De-Zheng Sun; Richard S. Lindzen

1993-06-01T23:59:59.000Z

155

Atmospheric Water Vapor Characteristics at 70°N  

Science Conference Proceedings (OSTI)

Using an extensive rawinsonde archive, characteristics of Arctic water vapor and its transports at 70°N are examined for the period 1974–1991. Monthly-mean profiles and vertically integrated values of specific humidity and meridional vapor fluxes ...

Mark C. Serreze; Roger G. Barry; John E. Walsh

1995-04-01T23:59:59.000Z

156

Vapor Pressure Measurement of Supercooled Water  

Science Conference Proceedings (OSTI)

A new dewpoint hygrometer was developed for subfreezing temperature application. Vapor pressure of supercooled water was determined by measuring temperatures at the dew-forming surface and the vapor source ice under the flux density balance, and ...

N. Fukuta; C. M. Gramada

2003-08-01T23:59:59.000Z

157

Intersubband Absorption at 1.55 ?M In Aln/Gan Multi Quantum Wells ...  

Science Conference Proceedings (OSTI)

Intersubband Absorption at 1.55 ?M In Aln/Gan Multi Quantum Wells Grown at 770 °C by Metal Organic Vapor Phase Epitaxy using Pulse Injection Method.

158

1997 Workshop on OMVPE  

Science Conference Proceedings (OSTI)

April 13-17, 1997 · Dana Point, California. OMVPE Logo. The 8th Biennial Workshop on Organometallic Vapor Phase Epitaxy (OMVPE), sponsored by the ...

159

Metamorphic Growth for High Quality Lattice-Mismatched III-V Solar ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 15th International Conference on Metal Organic Vapor Phase Epitaxy. Symposium, 15th International Conference on Metal Organic ...

160

Effects of Epitaxial Graphene Stacking, Strain, and Thickness ...  

Science Conference Proceedings (OSTI)

Register as a New User ... Additionally, we have examined epitaxial graphene with mobility values of 25 – 18,100 cm2/Vs, and show that Raman topography is a ...

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

LOW PRESSURE CHEMICAL VAPOR DEPOSITION OF POLYSILICON  

E-Print Network (OSTI)

THEORY The mass transport processes in low pressure chemical vapor deposition (LPCVD) are similar to those occuring in catalytic reactors

Gieske, R.J.

2011-01-01T23:59:59.000Z

162

Vapor Pressures and Heats of Vaporization of Primary Coal Tars  

Office of Scientific and Technical Information (OSTI)

/ PC92544-18 / PC92544-18 VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS FINAL REPORT Grant Dates: August, 1992 - November, 1996 Principal Authors: Eric M. Suuberg (PI) and Vahur Oja Report Submitted: April, 1997 Revised: July, 1997 Grant Number: DE-FG22-92PC92544 Report Submitted by: ERIC M. SUUBERG DIVISION OF ENGINEERING BROWN UNIVERSITY PROVIDENCE, RI 02912 TEL. (401) 863-1420 Prepared For: U. S. DEPT. OF ENERGY FEDERAL ENERGY TECHNOLOGY CENTER P.O. BOX 10940 PITTSBURGH, PA 15236 DR. KAMALENDU DAS, FETC, MORGANTOWN , WV TECHNICAL PROJECT OFFICER "US/DOE Patent Clearance is not required prior to the publication of this document" ii United States Government Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any

163

Means and method for vapor generation  

DOE Patents (OSTI)

A liquid, in heat transfer contact with a surface heated to a temperature well above the vaporization temperature of the liquid, will undergo a multiphase (liquid-vapor) transformation from 0% vapor to 100% vapor. During this transition, the temperature driving force or heat flux and the coefficients of heat transfer across the fluid-solid interface, and the vapor percentage influence the type of heating of the fluid--starting as "feedwater" heating where no vapors are present, progressing to "nucleate" heating where vaporization begins and some vapors are present, and concluding with "film" heating where only vapors are present. Unstable heating between nucleate and film heating can occur, accompanied by possibly large and rapid temperature shifts in the structures. This invention provides for injecting into the region of potential unstable heating and proximate the heated surface superheated vapors in sufficient quantities operable to rapidly increase the vapor percentage of the multiphase mixture by perhaps 10-30% and thereby effectively shift the multiphase mixture beyond the unstable heating region and up to the stable film heating region.

Carlson, Larry W. (Oswego, IL)

1984-01-01T23:59:59.000Z

164

The origin of high-temperature zones in vapor-dominated geothermal systems  

DOE Green Energy (OSTI)

Vapor-dominated geothermal systems are proposed to originate by downward extension (by the ''heat pipe'' mechanism) into hot dry fractured rock above a large cooling igneous intrusion. High temperature zones found by drilling are shallow parts of the original hot dry rock where the penetration of the vapor reservoir was limited, and hot dry rock may extend under much of these reservoirs. An earlier hot water geothermal system may have formed during an early phase of the heating episode.

Truesdell, Alfred H.

1991-01-01T23:59:59.000Z

165

Phase Field Simulations  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... The anisotropic solid-vapor surface energy for a 2D PFC hexagonal crystal is ... Finally, we examine the dynamic case of step-flow growth of a crystal into ... Thermal and Dispersed-Phase Analysis of Nano Fluid Using CFD-A Hybrid ... gas turbine power generation systems because of its high melting point, ...

166

Effect of higher water vapor content on TBC performance  

Science Conference Proceedings (OSTI)

Coal gasification, or IGCC (integrated gasification combined cycle), is one pathway toward cleaner use of coal for power generation with lower emissions. However, when coal-derived synthesis gas (i.e., syngas) is burned in turbines designed for natural gas, turbine manufacturers recommend 'derating,' or lowering the maximum temperature, which lowers the efficiency of the turbine, making electricity from IGCC more expensive. One possible reason for the derating is the higher water vapor contents in the exhaust gas. Water vapor has a detrimental effect on many oxidation-resistant high-temperature materials. In a turbine hot section, Ni-base superalloys are coated with a thermal barrier coating (TBC) allowing the gas temperature to be higher than the superalloy solidus temperature. TBCs have a low thermal conductivity ceramic top coating (typically Y{sub 2}O{sub 3}-stabilized ZrO{sub 2}, or YSZ) and an oxidation-resistant metallic bond coating. For land-based gas turbines, the industry standard is air plasma sprayed (APS) YSZ and high velocity oxygen fuel (HVOF) sprayed NiCoCrAlY bond coatings. To investigate the role of higher water vapor content on TBC performance and possible mitigation strategies, furnace cycling experiments were conducted in dry O{sub 2} and air with 10% (typical with natural gas or jet fuel) or 50 vol% water vapor. Cycle frequency and temperature were accelerated to one hour at 1100 C (with 10 minute cooling to {approx}30 C between each thermal cycle) to induce early failures in coatings that are expected to operate for several years with a metal temperature of {approx}900 C. Coupons (16 mm diameter x 2 mm thick) of commercial second-generation single crystal superalloy CMSX4 were HVOF coated on both sides with {approx}125 {micro}m of Ni-22wt%Co-17Cr-12Al either with 0.7Y or 0.7Y-0.3Hf-0.4Si. One side was then coated with 190-240 {micro}m of APS YSZ. Coatings were cycled until the YSZ top coating spalled. Figure 2 shows the results of the initial phase of experiments. Compared to dry O{sub 2}, the addition of 10% water vapor decreased the lifetime of MCrAlY by {approx}30% for the conventional CMSX4 substrates. Higher average lifetimes were observed with Hf in the bond coating, but a similar decrease in lifetime was observed when water vapor was added. The addition of Y and La to the superalloy substrate did not change the YSZ lifetime with 10% water vapor. However, increasing water vapor content from 10 to 50% did not further decrease the lifetime of either bond coating with the doped superalloy substrate. Thus, these results suggest that higher water vapor contents cannot explain the derating of syngas-fired turbines, and other factors such as sulfur and ash from imperfect syngas cleanup (or upset conditions) need to be explored. Researchers continue to study effects of water vapor on thermally grown alumina scale adhesion and growth rate, and are looking for bond coating compositions more resistant to oxidation in the presence of water vapor.

Pint, Bruce A [ORNL; Haynes, James A [ORNL

2012-01-01T23:59:59.000Z

167

Enhanced frequency up-conversion in Rb vapor  

E-Print Network (OSTI)

We demonstrate highly efficient generation of coherent 420 nm light via up-conversion of near-infrared lasers in a hot rubidium vapor cell. By optimizing pump polarizations and frequencies we achieve a single-pass conversion efficiency of 260%/W, significantly higher than in previous experiments. A full 2D exploration of the coherent light generation and fluorescence as a function of the pump frequencies reveals that coherent blue light is generated at 85Rb two-photon resonances, as predicted by theory, but at high vapor pressure it is suppressed in spectral regions that don't support phase matching or exhibit single-photon Kerr refraction. Favorable scaling of our current 1 mW blue beam power with additional pump power is predicted. Infrared pump polarization could be used for future intensity switching experiments.

Vernier, A; Riis, E; Arnold, A S

2009-01-01T23:59:59.000Z

168

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Prospective challengers to silicon, the long-reigning king of semiconductors for computer chips and other electronic devices, have to overcome silicon's superb collection of materials properties as well as sophisticated fabrication technologies refined by six decades of effort by materials scientists and engineers. Graphene, one of the latest contenders, has a rather impressive list of features of its own but has lacked a key characteristic of all semiconductors, an energy gap (band gap) in its electronic band structure. A multi-institutional collaboration under the leadership of researchers with Berkeley Lab and the University of California, Berkeley, have now demonstrated that growing an epitaxial film of graphene on a silicon carbide substrate results in a significant band gap, 0.26 electron volts (eV), an important step toward making graphene useful as a semiconductor.

169

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Prospective challengers to silicon, the long-reigning king of semiconductors for computer chips and other electronic devices, have to overcome silicon's superb collection of materials properties as well as sophisticated fabrication technologies refined by six decades of effort by materials scientists and engineers. Graphene, one of the latest contenders, has a rather impressive list of features of its own but has lacked a key characteristic of all semiconductors, an energy gap (band gap) in its electronic band structure. A multi-institutional collaboration under the leadership of researchers with Berkeley Lab and the University of California, Berkeley, have now demonstrated that growing an epitaxial film of graphene on a silicon carbide substrate results in a significant band gap, 0.26 electron volts (eV), an important step toward making graphene useful as a semiconductor.

170

New Regenerative Cycle for Vapor Compression Refrigeration  

SciTech Connect

The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and second step of compression. In the proposed system, the compressor compresses the vapor only to 50-60% of the final pressure, while the additional compression is provided by a jet device using internal potential energy of the working fluid flow. Therefore, the amount of mechanical energy required by a compressor is significantly reduced, resulting in the increase of efficiency (either COP or EER). The novelty of the cycle is in the equipment and in the way the multi-staging is accomplished. The anticipated result will be a new refrigeration system that requires less energy to accomplish a cooling task. The application of this technology will be for more efficient designs of: (1) Industrial chillers, (2) Refrigeration plants, (3) Heat pumps, (4) Gas Liquefaction plants, (5) Cryogenic systems.

Mark J. Bergander

2005-08-29T23:59:59.000Z

171

Coupling apparatus for a metal vapor laser  

DOE Patents (OSTI)

Coupling apparatus for a large bore metal vapor laser is disclosed. The coupling apparatus provides for coupling high voltage pulses (approximately 40 KV) to a metal vapor laser with a high repetition rate (approximately 5 KHz). The coupling apparatus utilizes existing thyratron circuits and provides suitable power input to a large bore metal vapor laser while maintaining satisfactory operating lifetimes for the existing thyratron circuits.

Ball, D.G.; Miller, J.L.

1993-02-23T23:59:59.000Z

172

Mercury Vapor (Kooten, 1987) | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor (Kooten, 1987) Mercury Vapor (Kooten, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor (Kooten, 1987) Exploration Activity Details Location Unspecified Exploration Technique Mercury Vapor Activity Date Usefulness useful DOE-funding Unknown Notes Surface soil-mercury surveys are an inexpensive and useful exploration tool for geothermal resources. ---- Surface geochemical surveys for mercury were conducted in 16 areas in 1979-1981 by ARCO Oil and Gas Company as part of its geothermal evaluation program. Three techniques used together have proved satisfactory in evaluating surface mercury data. These are contouring, histograms and cumulative frequency plots of the data. Contouring geochemical data and constructing histograms are standard

173

Thermoplastic Composite with Vapor Grown Carbon Fiber.  

E-Print Network (OSTI)

??Vapor grown carbon fiber (VGCF) is a new class of highly graphitic carbon nanofiber and offers advantages of economy and simpler processing over continuous-fiber composites.… (more)

Lee, Jaewoo

2005-01-01T23:59:59.000Z

174

Moisture Durability of Vapor Permeable Insulating Sheathing ...  

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

Existing Homes, Building Technologies Office (BTO) In this project, Building America team Building Science Corporation researched some of the ramifications of using exterior, vapor...

175

Water Vapor Fields Deduced from METEOSAT-1 Water Vapor Channel Data  

Science Conference Proceedings (OSTI)

A quasi-operational process for the determination of water vapor fields from METEPSAT-1 water vapor channel data is described. Each count of the WV picture is replaced by the corresponding mean relative humidity value using both the calibration ...

M. M. Poc; M. Roulleau

1983-09-01T23:59:59.000Z

176

NO-assisted molecular-beam epitaxial growth of nitrogen substituted EuO  

Science Conference Proceedings (OSTI)

We have investigated a method for substituting oxygen with nitrogen in EuO thin films, which is based on molecular beam epitaxy distillation with NO gas as the oxidizer. By varying the NO gas pressure, we produce crystalline, epitaxial EuO{sub 1-x}N{sub x} films with good control over the films' nitrogen concentration. In situ x-ray photoemission spectroscopy reveals that nitrogen substitution is connected to the formation Eu{sup 3+}4f{sup 6} and a corresponding decrease in the number of Eu{sup 2+}4f{sup 7}, indicating that nitrogen is being incorporated in its 3{sup -} oxidation state. While small amounts of Eu{sup 3+} in over-oxidized Eu{sub 1-{delta}}O thin films lead to a drastic suppression of the ferromagnetism, the formation of Eu{sup 3+} in EuO{sub 1-x}N{sub x} still allows the ferromagnetic phase to exist with an unaffected T{sub c}, thus providing an ideal model system to study the interplay between the magnetic f{sup 7} (J = 7/2) and the non-magnetic f{sup 6} (J = 0) states close to the Fermi level.

Wicks, R. [Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1 (Canada); Altendorf, S. G.; Caspers, C.; Kierspel, H.; Sutarto, R. [II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany); Tjeng, L. H. [II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany); Max Planck Institute for Chemical Physics of Solids, 01187 Dresden (Germany); Damascelli, A. [Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1 (Canada); Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4 (Canada)

2012-04-16T23:59:59.000Z

177

Structure and features of the surface morphology of A{sup 4}B{sup 6} chalcogenide epitaxial films  

Science Conference Proceedings (OSTI)

The structure and features of the surface morphology of Pb{sub 1-x}Mn{sub x}Se (x = 0.03) epitaxial films grown on freshly cleaved BaF{sub 2}(111) faces and PbSe{sub 1-x}S{sub x}(100) (x = 0.12) single-crystal wafers were investigated by molecular beam condensation and the hot-wall method. It is shown that the epitaxial films, in accordance with the data in the literature for other chalcogenides, grow in the (111) and (100) planes, repeating the substrate orientation. Black aggregates are observed on the film surface of the films grown. The results obtained are compared with the data in the literature and generalized for other chalcogenides: A{sup 4}B{sup 6}:Pb (S, Se, Te); Pb{sub 1-x}Sn{sub x} (S, Se, Te); and Pb{sub 1-x}Mn (Se, Te). It is established that the formation of black aggregates, which are second-phase inclusions on the surface of epitaxial films obtained by vacuum thermal deposition, is characteristic of narrow-gap A{sup 4}B{sup 6} chalcogenides.

Nuriyev, I. R., E-mail: afinnazarov@yahoo.com [Azerbaijan National Academy of Sciences, Institute of Physics (Azerbaijan)

2009-12-15T23:59:59.000Z

178

Field Studies of Soil Vapor Intrusion at a Vacant Manufactured Gas Plant (MGP) Site in Wisconsin  

Science Conference Proceedings (OSTI)

A comprehensive two-phase field-based research program was completed at a former manufactured gas plant (MGP) site located in Wisconsin during the summer of 2008. The purpose of this ongoing research study is to develop improved approaches and methodologies for characterizing the potential for vapor intrusion (VI) at MGP sites. This report describes the methods, results, and limited data interpretation of Phase I (Passive Soil Gas Survey) and Phase II (Soil, Groundwater, and Soil Gas Sampling) at the vac...

2009-06-30T23:59:59.000Z

179

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents (OSTI)

A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.

Novick, Vincent J.; Johnson, Stanley A.

1997-12-01T23:59:59.000Z

180

G-Band Vapor Radiometer Precipitable Water Vapor (GVRPWV) Value-Added Product  

SciTech Connect

The G-Band Vapor Radiometer Precipitable Water Vapor (GVRPWV) value-added product (VAP) computes precipitable water vapor using neural network techniques from data measured by the GVR. The GVR reports time-series measurements of brightness temperatures for four channels located at 183.3 ± 1, 3, 7, and 14 GHz.

Koontz, A; Cadeddu, M

2012-12-05T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

High sensitive quasi freestanding epitaxial graphene gassensor on 6H-SiC  

E-Print Network (OSTI)

We have measured the electrical response to NO$_2$, N$_2$, NH$_3$ and CO for epitaxial graphene and quasi freestanding epitaxial graphene on 6H-SiC substrates. Quasi freestanding epitaxial graphene shows a 6 fold increase in NO2 sensitivity compared to epitaxial graphene. Both samples show a sensitivity better than the experimentally limited 1 ppb. The strong increase in sensitivity of quasi freestanding epitaxial graphene can be explained by a Fermi-energy close to the Dirac Point leading to a strongly surface doping dependent sample resistance. Both sensors show a negligible sensitivity to N$_2$, NH$_3$ and CO.

Iezhokin, I; Brongersma, S H; Giesbers, A J M; Flipse, C F J

2013-01-01T23:59:59.000Z

182

Molecular beam epitaxy-grown wurtzite MgS thin films for solar-blind ultra-violet detection  

SciTech Connect

Molecular beam epitaxy grown MgS on GaAs(111)B substrate was resulted in wurtzite phase, as demonstrated by detailed structural characterizations. Phenomenological arguments were used to account for why wurtzite phase is preferred over zincblende phase or its most stable rocksalt phase. Results of photoresponse and reflectance measurements performed on wurtzite MgS photodiodes suggest a direct bandgap at around 5.1 eV. Their response peaks at 245 nm with quantum efficiency of 9.9% and enjoys rejection of more than three orders at 320 nm and close to five orders at longer wavelengths, proving the photodiodes highly competitive in solar-blind ultraviolet detection.

Lai, Y. H.; He, Q. L. [Nano Science and Nano Technology Program, The Hong Kong University of Science and Technology, HKSAR, People's Republic of China (China) [Nano Science and Nano Technology Program, The Hong Kong University of Science and Technology, HKSAR, People's Republic of China (China); Department of Physics and William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, HKSAR, People's Republic of China (China); Cheung, W. Y.; Lok, S. K.; Wong, K. S.; Sou, I. K. [Department of Physics and William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, HKSAR, People's Republic of China (China)] [Department of Physics and William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, HKSAR, People's Republic of China (China); Ho, S. K. [Faculty of Science and Technology, University of Macau, Macau, People's Republic of China (China)] [Faculty of Science and Technology, University of Macau, Macau, People's Republic of China (China); Tam, K. W. [Department of Electrical and Electronics Engineering, University of Macau, Macau, People's Republic of China (China)] [Department of Electrical and Electronics Engineering, University of Macau, Macau, People's Republic of China (China)

2013-04-29T23:59:59.000Z

183

Quantitative organic vapor-particle sampler  

DOE Patents (OSTI)

A quantitative organic vapor-particle sampler for sampling semi-volatile organic gases and particulate components. A semi-volatile organic reversible gas sorbent macroreticular resin agglomerates of randomly packed microspheres with the continuous porous structure of particles ranging in size between 0.05-10 .mu.m for use in an integrated diffusion vapor-particle sampler.

Gundel, Lara (Berkeley, CA); Daisey, Joan M. (Walnut Creek, CA); Stevens, Robert K. (Cary, NC)

1998-01-01T23:59:59.000Z

184

A New Global Water Vapor Dataset  

Science Conference Proceedings (OSTI)

A comprehensive and accurate global water vapor dataset is critical to the adequate understanding of water vapor's role in the earth's climate system. To begin to satisfy this need, the authors have produced a blended dataset made up of global, 5-...

David L. Randel; Thomas J. Greenwald; Thomas H. Vonder Haar; Graeme L. Stephens; Mark A. Ringerud; Cynthia L. Combs

1996-06-01T23:59:59.000Z

185

LNG fire and vapor control system technologies  

SciTech Connect

This report provides a review of fire and vapor control practices used in the liquefied natural gas (LNG) industry. Specific objectives of this effort were to summarize the state-of-the-art of LNG fire and vapor control; define representative LNG facilities and their associated fire and vapor control systems; and develop an approach for a quantitative effectiveness evaluation of LNG fire and vapor control systems. In this report a brief summary of LNG physical properties is given. This is followed by a discussion of basic fire and vapor control design philosophy and detailed reviews of fire and vapor control practices. The operating characteristics and typical applications and application limitations of leak detectors, fire detectors, dikes, coatings, closed circuit television, communication systems, dry chemicals, water, high expansion foam, carbon dioxide and halogenated hydrocarbons are described. Summary descriptions of a representative LNG peakshaving facility and import terminal are included in this report together with typical fire and vapor control systems and their locations in these types of facilities. This state-of-the-art review identifies large differences in the application of fire and vapor control systems throughout the LNG industry.

Konzek, G.J.; Yasutake, K.M.; Franklin, A.L.

1982-06-01T23:59:59.000Z

186

Atomic vapor laser isotope separation  

SciTech Connect

Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

Stern, R.C.; Paisner, J.A.

1985-11-08T23:59:59.000Z

187

Molecular beam epitaxy growth of exchange-biased PtMn/NiFe bilayers with a spontaneously ordered PtMn layer  

Science Conference Proceedings (OSTI)

We report the direct epitaxial growth of equiatomic ordered antiferromagnetic PtMn layers by molecular beam epitaxy. Such layers are used in giant magnetoresistance spin valve sensors as the antiferromagnetic pinning layer. Structural characterization and phase identification confirmed the spontaneous formation of the chemically ordered face-centered-tetragonal (L1{sub 0}) phase of PtMn with about 87.4% ordering. Based on the antiferromagnetic PtMn layer, we prepared exchange-biased PtMn/NiFe bilayers with various PtMn thicknesses. The exchange anisotropy field of the bilayer with NiFe grown on PtMn stabilizes at about 50 Oe beyond a PtMn thickness of 15 nm. Although the exchange anisotropy field is small compared to that of the polycrystalline system, the antiferromagnetic domain structure is stable over repetitive external magnetic field cycling and no training effect is observed.

Choi, Y. S.; Petford-Long, A. K.; Ward, R. C. C.; Fan, R.; Goff, J. P.; Hase, T. P. A. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Department of Physics, University of Durham, Durham DH1 3LE (United Kingdom)

2006-04-15T23:59:59.000Z

188

Stacked vapor fed amtec modules  

DOE Patents (OSTI)

The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.

Sievers, Robert K. (North Huntingdon, PA)

1989-01-01T23:59:59.000Z

189

Organic lateral heterojunction devices for vapor-phase chemical detection  

E-Print Network (OSTI)

As the U.S. is engaged in battle overseas, there is an urgent need for the development of sensors for early warning and protection of military forces against potential attacks. On the battlefields, improvised explosive ...

Ho, John C., 1980-

2009-01-01T23:59:59.000Z

190

Ninth International Conference on Metal Organic Vapor Phase ...  

Science Conference Proceedings (OSTI)

Hertz Rent-a-Car System has been selected as the Official Car Rental Company for the ICMOVPE IX. Special rates are being offered and will be honored up to ...

191

Regular Transient Loading Response in a Vapor-Phase  

E-Print Network (OSTI)

from a POTW using a compost bio?lter. ” Water Environ. Res.heat and mass transport within a compost bio?lter: I. ModelM. A. ?1995?. “Operation of compost based bio?lters under

Wright, W F; Schroeder, E D; Chang, Daniel P.Y.

2005-01-01T23:59:59.000Z

192

Ninth International Conference on Metal Organic Vapor Phase ...  

Science Conference Proceedings (OSTI)

Free sample copies of III-Vs Review and information on the Advanced ... on the market an innovative surface contamination analysis with the powerful TOF SIMS ... NIMTEC, located in Chandler, AZ, is a subsidiary of Japan Energy that sells ...

193

Regular Transient Loading Response in a Vapor-Phase  

E-Print Network (OSTI)

JOURNAL OF ENVIRONMENTAL ENGINEERING © ASCE / DECEMBER 2005ENVIRONMENTAL ENGINEERING © ASCE / DECEMBER 2005 / 1657 nol.must be ?led with the ASCE Managing Editor. The manuscript

Wright, W F; Schroeder, E D; Chang, Daniel P.Y.

2005-01-01T23:59:59.000Z

194

Silicon in functional epitaxial oxides: A new group of nanostructures  

Science Conference Proceedings (OSTI)

The ability to integrate low-dimensional crystalline silicon into crystalline insulators with high dielectric constant (high-k) can open the way for a variety of novel applications ranging from high-k replacement in future nonvolatile memory devices ... Keywords: Molecular beam epitaxy, Nanocluster, Nanostructures, Quantum well, Rare-earth oxides, Silicon

A. Fissel; A. Laha; E. Bugiel; D. Kühne; M. Czernohorsky; R. Dargis; H. J. Osten

2008-03-01T23:59:59.000Z

195

Ge epitaxial refill deposition techniques for fabricating pedestal transistor structures  

Science Conference Proceedings (OSTI)

An etch-epitaxial refill technique is described for the fabrication of integrated high-speed Ge transistor structures having a pedestal configuration. The device areas surrounding 0.1 ohm-cm mesa structures were refilled with Ge having a resistivity ...

V. J. Silvestri; T. B. Light; H. N. Yu; A. Reisman

1972-01-01T23:59:59.000Z

196

ARM - Field Campaign - Water Vapor IOP  

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

govCampaignsWater Vapor IOP govCampaignsWater Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Water Vapor IOP 2000.09.18 - 2000.10.08 Lead Scientist : Henry Revercomb Data Availability Yes For data sets, see below. Description Scientific hypothesis: 1. Microwave radiometer (MWR) observations of the 22 GHz water vapor line can accurately constrain the total column amount of water vapor (assuming a calibration accuracy of 0.5 degC or better, which translates into 0.35 mm PWV). 2. Continuous profiling by Raman lidar provides a stable reference for handling sampling problems and observes a fixed column directly above the site only requiring a single height- independent calibration factor. 3. Agreement between the salt-bath calibrated in-situ probes, chilled

197

Low Frequency Acoustic Resonance Studies of the Liquid-Vapor Transition in Silica Aerogel  

E-Print Network (OSTI)

Fluid phase transitions in porous media are a powerful probe of the effect of confinement and disorder on phase transitions. Aerogel may provide a model system in which to study the effect of dilute impurities on a variety of phase transitions. In this paper we present a series of low frequency acoustic experiments on the effect of aerogel on the liquid-vapor phase transition. Acoustic resonators were used to study the liquid-vapor transition in two fluids (helium and neon) and in two different porosity aerogels (95% and 98%). While effective coexistence curves could be mapped out, the transition was sometimes difficult to pinpoint, leading to doubt as to whether this transition can be treated as an equilibrium macroscopic phase transition at all.

Tobias Herman; John Beamish

2005-06-30T23:59:59.000Z

198

Insights in High-Temperature Superconductivity from the Study of Films and Heterostructures Synthesized by Molecular Beam Epitaxy  

Science Conference Proceedings (OSTI)

Using molecular beam epitaxy, we synthesize atomically smooth thin films, multilayers and superlattices of cuprate high-temperature superconductors (HTS). Such heterostructures enable novel experiments that probe the basicphysics of HTS. For example, we have established that HTS and antiferromagnetic phases separate on Ångstrom scale, while the pseudo-gap state apparently mixes with HTS over an anomalously large length scale ('Giant Proximity Effect'). Here, we briefly review our most recent experiments on such films and superlattices. The new results include an unambiguous demonstration of strong coupling of in-plane charge excitations to out-of-plane lattice vibrations and the discovery of interface HTS.

Bozovic,I.

2009-01-09T23:59:59.000Z

199

Methods of preparing flexible photovoltaic devices using epitaxial liftoff, and preserving the integrity of growth substrates used in epitaxial growth  

DOE Patents (OSTI)

There is disclosed methods of making photosensitive devices, such as flexible photovoltaic (PV) devices, through the use of epitaxial liftoff. Also described herein are methods of preparing flexible PV devices comprising a structure having a growth substrate, wherein the selective etching of protective layers yields a smooth growth substrate that us suitable for reuse.

Forrest, Stephen R; Zimmerman, Jeramy; Lee, Kyusang; Shiu, Kuen-Ting

2013-02-19T23:59:59.000Z

200

Cosine (Cobalt Silicide Growth Through Nitrogen-Induced Epitaxy) Process For Epitaxial Cobalt Silicide Formation For High Performance Sha  

DOE Patents (OSTI)

A method for forming an epitaxial cobalt silicide layer on a MOS device includes sputter depositing cobalt in an ambient to form a first layer of cobalt suicide on a gate and source/drain regions of the MOS device. Subsequently, cobalt is sputter deposited again in an ambient of argon to increase the thickness of the cobalt silicide layer to a second thickness.

Lim, Chong Wee (Urbana, IL); Shin, Chan Soo (Daejeon, KR); Gall, Daniel (Troy, NY); Petrov, Ivan Georgiev (Champaign, IL); Greene, Joseph E. (Champaign, IL)

2004-09-28T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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.


201

Mercury Vapor At Desert Peak Area (Varekamp & Buseck, 1983) ...  

Open Energy Info (EERE)

Mercury Vapor At Desert Peak Area (Varekamp & Buseck, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Desert Peak Area...

202

Mercury Vapor At Socorro Mountain Area (Kooten, 1987) | Open...  

Open Energy Info (EERE)

Mercury Vapor At Socorro Mountain Area (Kooten, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Socorro Mountain Area...

203

Abstract: Apparatus for Measuring Vapor-Liquid Equilibrium ...  

Science Conference Proceedings (OSTI)

... Measurements of the vapor pressures and saturated liquid densities of ethanol and the vapor pressure of an ethanol water mixture (ethanol=0.6743 ...

204

Mercury Vapor At Mccoy Geothermal Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

Mercury Vapor At Mccoy Geothermal Area (DOE GTP) Exploration Activity Details Location Mccoy Geothermal Area Exploration Technique Mercury Vapor Activity Date Usefulness not...

205

High Growth Rate of Epitaxial Silicon-Carbon Alloys by High-Order Silane Precursor and Chemical Vapor Deposition  

E-Print Network (OSTI)

rates typically achieved by disilane and silane, respectively, at 575o C. The rate at present is limited precursor HOS than disilane in CVD, even at lower temperatures. Our current growth rates of Si1-yCy alloys

206

Chemical Vapor Deposition Epitaxy of Silicon and Silicon-Carbon Alloys at High Rates and Low Temperatures using Neopentasilane  

E-Print Network (OSTI)

dichlorosilane (slowest) to silane (SiH4) to disilane (Si2H6) (data from our lab) to trisilane (Si3H8) (Ref 2

207

Water vapor retrieval over many surface types  

SciTech Connect

In this paper we present a study of of the water vapor retrieval for many natural surface types which would be valuable for multi-spectral instruments using the existing Continuum Interpolated Band Ratio (CIBR) for the 940 nm water vapor absorption feature. An atmospheric code (6S) and 562 spectra were used to compute the top of the atmosphere radiance near the 940 nm water vapor absorption feature in steps of 2.5 nm as a function of precipitable water (PW). We derive a novel technique called ``Atmospheric Pre-corrected Differential Absorption`` (APDA) and show that APDA performs better than the CIBR over many surface types.

Borel, C.C.; Clodius, W.C.; Johnson, J.

1996-04-01T23:59:59.000Z

208

Modeling engine oil vaporization and transport of the oil vapor in the piston ring pack on internal combustion engines.  

E-Print Network (OSTI)

??A model was developed to study engine oil vaporization and oil vapor transport in the piston ring pack of internal combustion engines. With the assumption… (more)

Cho, Yeunwoo, 1973-

2004-01-01T23:59:59.000Z

209

Analysis of binary vapor turbines  

DOE Green Energy (OSTI)

The effect the binary mixture has on the turbine is examined in terms of design and cost. Several flow theories for turbines and turbine blading are reviewed. The similarity method, which uses dimensionless parameters, is used in determining rotative speeds and diameters for a variety of inlet temperatures and exit pressures. It is shown that the ratio of exit to inlet specific volume for each component in the mixture is the same for each specie. The specific volume ratio constraints are combined with the temperature equalities, the condenser pressure, and the total inlet entropy to form the constraints necessary to determine the exit state uniquely in an isentropic expansion. The non-isentropic exit state is found in a similar manner. The expansion process is examined for several cases and compared with the expansion of a single component vapor. Finally, in order to maintain high efficiency and to meet the criteria which makes the similarity method valid at high inlet temperatures, turbine multistaging is examined and a sample case is given for a two stage turbine.

Bliss, R.W.; Boehm, R.F.; Jacobs, H.R.

1976-12-01T23:59:59.000Z

210

Developmental of a Vapor Cloud Explosion Risk Analysis Tool Using Exceedance Methodology  

E-Print Network (OSTI)

In development projects, designers should take into consideration the possibility of a vapor cloud explosion in the siting and design of a process plant from day one. The most important decisions pertinent to the location of different process areas, separation between different areas, location of occupied buildings and overall layout may be made at the conceptual stage of the project. During the detailed design engineering stage the final calculation of gas explosion loads is an important activity. However, decisions related to the layout and location of occupied buildings at this stage could be very costly. Therefore, at the conceptual phase of the development project for a hydrocarbon facility, it would be helpful to get a picture of possible vapor cloud explosion loads to be used in studying various options. This thesis presents the analytical parameters that are used in vapor cloud explosion risk analysis. It proposes a model structure for the analysis of vapor cloud explosion risks to buildings based on exceedance methodology. This methodology was developed in a computer program which is used to support this thesis. The proposed model considers all possible gas release scenarios through the use of the Monte Carlo simulation. The risk of vapor cloud explosions can be displayed using exceedance curves. The resulting model provides a predictive tool for vapor cloud explosion problems at the early stages of development projects, particularly in siting occupied buildings in onshore hydrocarbon facilities. It can also be used as a quick analytical tool for investigating various aspects of vapor cloud explosions. This model has been applied to a case study, a debutanizer process unit. The model was used to explore the different alternatives of locating a building near the facility. The results from the model were compared to the results of other existing software to determine the model validity. The results show that the model can effectively examine the risk of vapor cloud explosions.

Alghamdi, Salem

2011-08-01T23:59:59.000Z

211

Observed annual and interannual variations in tropospheric water vapor  

SciTech Connect

Radiosonde observations from a global network of 56 radiosonde stations for 1973-1990 are used to describe and quantify annual and interannual variations of tropospheric water vapor. Taking care to identify data inhomogeneities related to changes in instruments or observing practices, monthly mean and anomaly data sets are constructed for dew point, specific humidity, relative humidity, temperature and precipitable water from the surface to 500 mb. Local annual cycles of tropospheric humidity can be classified according to the amplitude and phase of humidity variations which define five humidity regimes. For two regimes, both in middle and high latitudes, relative humidity is fairly constant while the annual cycle of precipitable water is in phase with that of temperature. At some midlatitude stations with a monsoon-like climate, seasonal relative humidity variations are large. In the tropics, seasonal relative humidity variations, especially above the boundary layer, dominate the annual cycle of precipitable water, and precipitable water variations are not related to temperature variations. Correlations of temperature and specific humidity anomalies are generally positive outside the tropics, suggesting that atmospheric warming is associated with increases in water vapor content. However, correlations of temperature and relative humidity anomalies are sometimes not significant and are often negative (e.g., in mid- and high latitude continental regions). Thus relative humidity is not always insensitive to temperature changes. In the tropics, tropospheric water vapor and temperature variations are not well correlated. An empirical orthogonal function analysis of tropical specific humidity variations identified two important modes of variability. The first is a step-like increase in specific humidity that occurred in about 1976-1977, and the second is associated with the El Nino phenomenon.

Gaffen, D.J.

1992-01-01T23:59:59.000Z

212

Perfluorocarbon vapor tagging of blasting cap detonators  

DOE Patents (OSTI)

A plug for a blasting cap is made of an elastomer in which is dissolved a perfluorocarbon. The perfluorocarbon is released as a vapor into the ambient over a long period of time to serve as a detectable taggant.

Dietz, Russell N. (Shoreham, NY); Senum, Gunnar I. (Patchogue, NY)

1981-01-01T23:59:59.000Z

213

Perfluorocarbon vapor tagging of blasting cap detonators  

SciTech Connect

A plug for a blasting cap is made of an elastomer in which is dissolved a perfluorocarbon. The perfluorocarbon is released as a vapor into the ambient over a long period of time to serve as a detectable taggant.

Dietz, R.N.; Senum, G.I.

1981-03-17T23:59:59.000Z

214

Chemical vapor depositing of metal fluorides  

Science Conference Proceedings (OSTI)

High Purity BeF2 and BeF2–AlF3glasses have been deposited by the chemical vapor deposition technique using beryllium and aluminum 1

A. Sarhangi; J. M. Power

1992-01-01T23:59:59.000Z

215

Chemical vapor deposition of antimicrobial polymer coatings  

E-Print Network (OSTI)

There is large and growing interest in making a wide variety of materials and surfaces antimicrobial. Initiated chemical vapor deposition (iCVD), a solventless low-temperature process, is used to form thin films of polymers ...

Martin, Tyler Philip, 1977-

2007-01-01T23:59:59.000Z

216

Chemical vapor deposition of functionalized isobenzofuran polymers  

E-Print Network (OSTI)

This thesis develops a platform for deposition of polymer thin films that can be further tailored by chemical surface modification. First, we explore chemical vapor deposition of functionalized isobenzofuran films using ...

Olsson, Ylva Kristina

2007-01-01T23:59:59.000Z

217

Tropospheric Water Vapor and Climate Sensitivity  

Science Conference Proceedings (OSTI)

Estimates are made of the effect of changes in tropospheric water vapor on the climate sensitivity to doubled carbon dioxide (CO2), using a coarse resolution atmospheric general circulation model coupled to a slab mixed layer ocean. The ...

Edwin K. Schneider; Ben P. Kirtman; Richard S. Lindzen

1999-06-01T23:59:59.000Z

218

Chemical vapor infiltration using microwave energy  

DOE Patents (OSTI)

This invention is comprised of a method for producing reinforced ceramic composite articles by means of chemical vapor infiltration and deposition in which an inverted temperature gradient is utilized. Microwave energy is the source of heat for the process.

Devlin, D.J.; Currier, R.P.; Laia, J.R.; Barbero, R.S.

1992-12-31T23:59:59.000Z

219

Faceted ceramic fibers, tapes or ribbons and epitaxial devices therefrom  

SciTech Connect

A crystalline article includes a single-crystal ceramic fiber, tape or ribbon. The fiber, tape or ribbon has at least one crystallographic facet along its length, which is generally at least one meter long. In the case of sapphire, the facets are R-plane, M-plane, C-plane or A-plane facets. Epitaxial articles, including superconducting articles, can be formed on the fiber, tape or ribbon.

Goyal, Amit (Knoxville, TN)

2012-07-24T23:59:59.000Z

220

CORRELATIONS BETWEEN VAPOR SATURATION, FLUID COMPOSITION, AND WELL DECLINE IN LARDERELLO  

Science Conference Proceedings (OSTI)

A large body of field data from Larderello shows striking temporal correlations between decline of well flow-rate, produced gas/steam ratio, chloride concentration and produced vapor fraction. The latter is inferred from measured concentrations of non-condensible gases in samples of well fluid, using chemical phase equilibrium principles. Observed temporal changes in the vapor fractions can be interpreted in term of a ''multiple source'' model, as suggested by D'Amore and Truesdell (1979). This provides clues to the dynamics of reservoir depletion, and to the evaluation of well productivity and longevity.

D'Amore, F.; Pruess, K.

1985-01-22T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Growth of Thick, On-Axis SiC Epitaxial Layers by High Temperature ...  

Science Conference Proceedings (OSTI)

... Layers by High Temperature Halide CVD for High Voltage Power Devices ... rate, high temperature process ideally suited for thick epitaxial requirements.

222

Process for depositing an oxide epitaxially onto a silicon substrate and structures prepared with the process  

DOE Patents (OSTI)

A process and structure involving a silicon substrate utilizes an ultra high vacuum and molecular beam epitaxy (MBE) methods to grow an epitaxial oxide film upon a surface of the substrate. As the film is grown, the lattice of the compound formed at the silicon interface becomes stabilized, and a base layer comprised of an oxide having a sodium chloride-type lattice structure grows epitaxially upon the compound so as to cover the substrate surface. A perovskite may then be grown epitaxially upon the base layer to render a product which incorporates silicon, with its electronic capabilities, with a perovskite having technologically-significant properties of its own.

McKee, Rodney A. (Kingston, TN); Walker, Frederick J. (Oak Ridge, TN)

1993-01-01T23:59:59.000Z

223

A5, Photovoltaic-Quality Silicon Epitaxy by Hot-Wire CVD at Glass ...  

Science Conference Proceedings (OSTI)

However, PV applications require that the epitaxy be done at high growth rates and ... Using a simple growth rate model, we have optimized gas utilization and ...

224

Deposition of hetero-epitaxial In{sub 2}O{sub 3} thin films by molecular beam epitaxy  

SciTech Connect

Highly oriented thin film In{sub 2}O{sub 3} was heteroepitaxially grown on optically polished (100) plane of single crystalline yttria stabilized zirconia (YSZ) substrate using Molecular Beam Epitaxy (MBE). Full-width at half-maximum (FWHM) of X-ray rocking-curve showed 0.08{degree} for In{sub 2}O{sub 3} 200 nm thick layers indicating that excellent uniformity orientation compared with the heteroepitaxially-grown In{sub 2}O{sub 3} epitaxially deposited by the conventional methods such as electron-beam (e-beam) evaporation or sputtering method. The minimum yield ({chi}{sub min}) of the MBE grown in In{sub 2}O{sub 3} film of Rutherford Backscattering Spectrometry (RBS) was also extremely small value 3.1%, implying the very high crystallinity.

Taga, N.; Maekawa, M. [Asahi Glass Co., Ltd., Yokohama (Japan). Research Center; Shigesato, Y.; Yasui, I. [Univ. of Tokyo (Japan). Inst. of Industrial Science; Haynes, T.E. [Oak Ridge National Lab., TN (United States). Solid State Div.

1996-05-01T23:59:59.000Z

225

Giant magnetoresistive structures based on CrO{sub 2} with epitaxial RuO{sub 2} as the spacer layer  

Science Conference Proceedings (OSTI)

Epitaxial ruthenium dioxide (RuO{sub 2})/chromium dioxide(CrO{sub 2}) thin film heterostructures have been grown on (100)-TiO{sub 2} substrates by chemical vapor deposition. Both current-in-plane (CIP) and current-perpendicular-to-plane (CPP) giant magnetoresistive stacks were fabricated with either Co or another epitaxial CrO{sub 2} layer as the top electrode. The Cr{sub 2}O{sub 3} barrier, which forms naturally on CrO{sub 2} surfaces, is no longer present after the RuO{sub 2} deposition, resulting in a highly conductive interface that has a resistance at least four orders of magnitude lower. However, only very limited magnetoresistance (MR) was observed. Such low MR is due to the appearance of a chemically and magnetically disordered layer at the CrO{sub 2} and RuO{sub 2} interfaces when Cr{sub 2}O{sub 3} is transformed into rutile structures during its intermixing with RuO{sub 2}.

Miao, G.X.; Gupta, A.; Sims, H.; Butler, W.H.; Ghosh, S.; Xiao Gang [Physics Department, Brown University, Providence, Rhode Island 02912 (United States); Center for Materials for Information Technology, University of Alabama, Tuscaloosa, Alabama 35487 (United States); Department of Electrical and Computer Engineering, University of Illinois, Chicago, Illinois 60607 (United States); Physics Department, Brown University, Providence, Rhode Island 02912 (United States)

2005-05-15T23:59:59.000Z

226

Page 1 of 2 `5-Phase' EOS: A Tabular H2O EOS for Shock Physics Codes  

E-Print Network (OSTI)

of the Table The 5-Phase H2O tabular equation of state model includes ice Ih, ice VI, ice VII, liquid determined phase boundaries except for the artificial ice Ih-ice VI boundary and the adjacent liquid boundary density phase boundary occupied by the equilibrium mixtures of ice Ih-vapor and liquid-vapor. The tension

Stewart, Sarah T.

227

The influence of ice nucleation mode and ice vapor growth on simulation of  

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

The influence of ice nucleation mode and ice vapor growth on simulation of The influence of ice nucleation mode and ice vapor growth on simulation of arctic mixed-phase clouds Avramov, Alexander The Pennsylvania State University Category: Modeling Mixed-phase arctic stratus clouds are the predominant cloud type in the Arctic . Perhaps one of the most intriguing of their features is that they tend to have liquid tops that precipitate ice. Despite the fact that this situation is colloidally unstable, these cloud systems are quite long lived - from a few days to over a couple of weeks. Previous studies have suggested that this longevity may be due to a paucity of ice nucleating aerosols (ice nuclei, or IN) in the Arctic. Such studies have shown that small changes in IN concentrations can cause large changes in the amount of liquid water within a mixed-phase stratus deck. We use the Regional

228

The adsorption-controlled growth of LuFe{sub 2}O{sub 4} by molecular-beam epitaxy  

Science Conference Proceedings (OSTI)

We report the growth of single-phase (0001)-oriented epitaxial films of the purported electronically driven multiferroic, LuFe{sub 2}O{sub 4}, on (111) MgAl{sub 2}O{sub 4}, (111) MgO, and (0001) 6H-SiC substrates. Film stoichiometry was regulated using an adsorption-controlled growth process by depositing LuFe{sub 2}O{sub 4} in an iron-rich environment at pressures and temperatures where excess iron desorbs from the film surface during growth. Scanning transmission electron microscopy reveals reaction-free film-substrate interfaces. The magnetization increases rapidly below 240 K, consistent with the paramagnetic-to-ferrimagnetic phase transition of bulk LuFe{sub 2}O{sub 4}. In addition to the {approx}0.35 eV indirect band gap, optical spectroscopy reveals a 3.4 eV direct band gap at the gamma point.

Brooks, Charles M. [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853-1501 (United States); Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Misra, Rajiv; Schiffer, Peter [Department of Physics and Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Mundy, Julia A. [School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States); Zhang Lei, A.; Liu Zikui [Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Holinsworth, Brian S.; O'Neal, Kenneth R.; Musfeldt, Janice L. [Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996 (United States); Heeg, Tassilo [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853-1501 (United States); Zander, Willi; Schubert, J. [Peter Gruenberg Institut (PGI-9), JARA-Fundamentals of Future Information Technologies, Research Centre Juelich, D-52425 Juelich (Germany); Muller, David A. [School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853 (United States); Schlom, Darrell G. [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853-1501 (United States); Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853 (United States)

2012-09-24T23:59:59.000Z

229

Vapor scavenging by atmospheric aerosol particles  

Science Conference Proceedings (OSTI)

Particle growth due to vapor scavenging was studied using both experimental and computational techniques. Vapor scavenging by particles is an important physical process in the atmosphere because it can result in changes to particle properties (e.g., size, shape, composition, and activity) and, thus, influence atmospheric phenomena in which particles play a role, such as cloud formation and long range transport. The influence of organic vapor on the evolution of a particle mass size distribution was investigated using a modified version of MAEROS (a multicomponent aerosol dynamics code). The modeling study attempted to identify the sources of organic aerosol observed by Novakov and Penner (1993) in a field study in Puerto Rico. Experimentally, vapor scavenging and particle growth were investigated using two techniques. The influence of the presence of organic vapor on the particle`s hydroscopicity was investigated using an electrodynamic balance. The charge on a particle was investigated theoretically and experimentally. A prototype apparatus--the refractive index thermal diffusion chamber (RITDC)--was developed to study multiple particles in the same environment at the same time.

Andrews, E.

1996-05-01T23:59:59.000Z

230

Atomic-level investigation of the growth of Si/Ge by ultrahigh vacuum chemical vapor deposition  

SciTech Connect

Si and Ge films can be prepared under ultrahigh vacuum conditions by chemical vapor deposition using disilane and digermane as source gases. These gases offer a high sticking probability, and are suitable for atomic layer epitaxy. Using synchrotron radiation photoemission spectroscopy and scanning tunneling microscopy, we have examined the surface processes associated with the heteroepitaxial growth of Ge/Si. The measured surface-induced shifts and chemical shifts of the Si 2p and Ge 3d core levels allow us to identify the surface species and to determine the surface chemical composition, and this information is correlated with the atomic features observed by scanning tunneling microscopy. Issues related to precursor dissociation, attachment to dangling bonds, diffusion, surface segregation, growth morphology, and pyrolytic reaction pathways will be discussed. {copyright} {ital 1997 American Vacuum Society.}

Lin, D. [Institute of Physics, National Chiao-Tung University, Hsinchu, Taiwan, Republic of (China)] [Institute of Physics, National Chiao-Tung University, Hsinchu, Taiwan, Republic of (China); Miller, T.; Chiang, T. [Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States)] [Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States)

1997-05-01T23:59:59.000Z

231

High-pressure vapor-liquid equilibria in the propane-1-propanol system  

SciTech Connect

High-pressure isothermal vapor liquid equilibrium data were measured for the propane-1-propanol system at 81.6, 105.2, and 120.1 C in a static equilibrium cell with liquid-phase sampling by a piston-driven sampling rod and homogenizing the sample with a static jet mixer. The vapor phase was sampled by releasing it into an evacuated manifold, and the gas chromatograph was calibrated with a new variable volumetric device. Satisfactory modeling was achieved with the combined method using the UNIQUAC equation with equations of sate: the group contribution EOS, Peng-Robinson EOS, or the two-parameter Virial EOS. Differences between the measured and calculated vapor-phase mole fractions, however, were significant for the lower pressure regions of the 81.6 and 120.1 C isotherms. UNIQUAC parameters, hitherto unavailable, with fairly strong temperature dependence in the 81.6 to 120.1 C range are proposed for the system. The covariance matrix indicated a significant correlation among the parameters. The classical mixing rule interaction parameters required for the original Peng-Robinson EOS in the combined method were obtained using the direct method and were temperature-independent for the isotherms for which the propane was supercritical. The possibility of propane/1-propanol immiscibility was theoretically examined according to the criteria of Baker et al. The plots of Gibbs energy of mixing vs. phase mole fractions did not indicate liquid-phase splitting, but the inferences are EOS-dependent and must await visual confirmation. The authors earlier vapor-phase thermodynamic consistency test indicated the data for all three data sets not to be inconsistent.

Muehlbauer, A.L.; Raal, J.D. (Univ. of Natal, Durban (South Africa))

1993-04-01T23:59:59.000Z

232

atmospheric water vapor | OpenEI  

Open Energy Info (EERE)

atmospheric water vapor atmospheric water vapor Dataset Summary Description (Abstract): Monthly Average Solar Resource for 2-axis tracking concentrating collectors for Mexico, Central America, and the Caribbean Islands. (Purpose): Provide information on the solar resource potential for the data domain. The insolation values represent the average solar energy available to a concentrating collector, such as a dish collector, which tracks the sun continuously. Source NREL Date Released July 31st, 2006 (8 years ago) Date Updated October 30th, 2007 (7 years ago) Keywords atmospheric water vapor Carribean Islands Central America DNI GIS Mexico NREL GEF solar SWERA UNEP Data application/zip icon Download Shapefile (zip, 247.8 KiB) text/csv icon Download Data (csv, 370.6 KiB) Quality Metrics Level of Review Some Review

233

ARM - Field Campaign - Water Vapor IOP  

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

govCampaignsWater Vapor IOP govCampaignsWater Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Water Vapor IOP 1996.09.10 - 1996.09.30 Lead Scientist : Henry Revercomb For data sets, see below. Summary SCHEDULE This IOP will be conducted from September 10 - 30, 1996 (coincident with the Fall ARM-UAV IOP). Instruments that do not require supervision will be operated continuously during this period. Instruments that do require supervision are presently planned to be operated for 8-hour periods each day. Because it is necessary to cover as broad a range of environmental conditions as possible, the daily 8-hour period will be shifted across the diurnal cycle as deemed appropriate during the IOP (but will be maintained as a contiguous 8-hour block).

234

atmoshperic water vapor | OpenEI  

Open Energy Info (EERE)

atmoshperic water vapor atmoshperic water vapor Dataset Summary Description (Abstract): Monthly Average Solar Resource for flat-plate collectors tilted at latitude for China. Source NREL Date Released April 12th, 2005 (9 years ago) Date Updated October 30th, 2007 (7 years ago) Keywords atmoshperic water vapor China GEF GIS NREL solar SWERA TILT UNEP Data application/zip icon Download Shapefile (zip, 625.6 KiB) text/csv icon Download Data (csv, 704.1 KiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Time Period 01/01/1985 - 12/31/1991 License License Open Data Commons Public Domain Dedication and Licence (PDDL) Comment Rate this dataset Usefulness of the metadata Average vote Your vote Usefulness of the dataset Average vote Your vote Ease of access

235

Lattice-registered growth of GaSb on Si (211) with molecular beam epitaxy  

Science Conference Proceedings (OSTI)

A GaSb film was grown on a Si(211) substrate using molecular beam epitaxy indicating full lattice relaxation as well as full lattice registration and dislocation-free growth in the plane perpendicular to the [01 - 1]-direction. Heteroepitaxy of GaSb on a Si(211) substrate is dominated by numerous first order and multiple higher order micro-twins. The atomic-resolved structural study of GaSb films by high-angle annular dark-field scanning transmission electron microscopy reveals that slight tilt, along with twinning, favors the lattice registry to Si(211) substrates. Preferential bonding of impinging Ga and Sb atoms at the interface due to two distinctive bonding sites on the Si(211) surface enables growth that is sublattice-ordered and free of anti-phase boundaries. The role of the substrate orientation on the strain distribution of GaSb epilayers is further elucidated by investigating the local change in the lattice parameter using the geometric phase analysis method and hence effectiveness of the lattice tilting in reducing the interfacial strain was confirmed further.

Hosseini Vajargah, S.; Botton, G. A. [Department of Materials Science and Engineering, McMaster University, Hamilton, Ontario L8S 4L7 (Canada); Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Canadian Centre for Electron Microscopy, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Ghanad-Tavakoli, S. [Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4L7 (Canada); Preston, J. S.; Kleiman, R. N. [Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4L7 (Canada); Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4L7 (Canada)

2012-11-01T23:59:59.000Z

236

Improved thermal stability of Ni-silicides on Si: C epitaxial layers  

Science Conference Proceedings (OSTI)

The thermal stability of Ni-silicides on tensily strained in situ P doped Si:C epitaxial layers was evaluated. The baseline Ni silicidation process was shown to be compatible with Si:C Recessed Source-Drain (RSD) stressors for NMOS strain engineering ... Keywords: Epitaxy, Ni, SiC stressors, Silicide, Thermal stability

V. Machkaoutsan; S. Mertens; M. Bauer; A. Lauwers; K. Verheyden; K. Vanormelingen; P. Verheyen; R. Loo; M. Caymax; S. Jakschik; D. Theodore; P. Absil; S. G. Thomas; E. H. A. Granneman

2007-11-01T23:59:59.000Z

237

Stability and charge transfer at the interface between SiC(0001) and epitaxial graphene  

Science Conference Proceedings (OSTI)

Using density functional calculations, we address the energetics of the interface between the SiC(0001) substrate and the first covalently bonded epitaxial graphene layer. We consider a 63x63R30^o geometry showing the experimental periodicity, a simplified ... Keywords: Charge transfer, Energetic stability, Epitaxial graphene, Interfaces, Silicon carbide

Gabriele Sclauzero; Alfredo Pasquarello

2011-07-01T23:59:59.000Z

238

Si-nanoclusters embedded into epitaxial rare earth oxides: Potential candidate for nonvolatile memory applications  

Science Conference Proceedings (OSTI)

Using an unconventional approach, single crystalline Si-nanoclusters (Si-NCs) with uniform size and higher density were embedded into epitaxial rare earth oxide with two-dimensional spatial arrangements at a defined distance from the substrate using ... Keywords: Epitaxial rare earth oxide, MBE, Nonvolatile memory, Si-nanocluster

Apurba Laha; E. Bugiel; A. Fissel; H. J. Osten

2008-12-01T23:59:59.000Z

239

Integration of functional epitaxial oxides into silicon: from high-k application to nanostructures  

Science Conference Proceedings (OSTI)

We will present results for crystalline gadolinium oxides on silicon in the cubic bixbyite structure grown by solid source molecular beam epitaxy. Additional oxygen supply during growth improves the dielectric properties significantly. Experimental results ... Keywords: Gadolinium oxide, Heterostructures, High-k material, Molecular beam epitaxy

H. J. Osten; M. Czernohorsky; R. Dargis; A. Laha; D. Kühne; E. Bugiel; A. Fissel

2007-09-01T23:59:59.000Z

240

Engineering the interface between epitaxial lanthanide oxide thin films and Si substrates: a route towards tuning the electrical properties  

Science Conference Proceedings (OSTI)

The impact of interface layer composition on electrical properties of epitaxial Gd"2O"3 thin films on Si(001) substrates have been investigated. The electrical properties of epitaxial Gd"2O"3 thin films were improved significantly by controlled modification ... Keywords: Epitaxy, Gd2O3, High-K, Interface engineering

Apurba Laha; A. Fissel; H. J. Osten

2007-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Thermal electric vapor trap arrangement and method  

DOE Patents (OSTI)

A technique for trapping vapor within a section of a tube is disclosed herein. This technique utilizes a conventional, readily providable thermal electric device having a hot side and a cold side and means for powering the device to accomplish this. The cold side of this device is positioned sufficiently close to a predetermined section of the tube and is made sufficiently cold so that any condensable vapor passing through the predetermined tube section is condensed and trapped, preferably within the predetermined tube section itself.

Alger, Terry (Tracy, CA)

1988-01-01T23:59:59.000Z

242

Adsorption of water vapor on reservoir rocks  

DOE Green Energy (OSTI)

Progress is reported on: adsorption of water vapor on reservoir rocks; theoretical investigation of adsorption; estimation of adsorption parameters from transient experiments; transient adsorption experiment -- salinity and noncondensible gas effects; the physics of injection of water into, transport and storage of fluids within, and production of vapor from geothermal reservoirs; injection optimization at the Geysers Geothermal Field; a model to test multiwell data interpretation for heterogeneous reservoirs; earth tide effects on downhole pressure measurements; and a finite-difference model for free surface gravity drainage well test analysis.

Not Available

1993-07-01T23:59:59.000Z

243

Epitaxial growth of MgO and Fe/MgO/Fe magnetic tunnel junctions on (100)-Si by molecular beam epitaxy  

SciTech Connect

Epitaxial growth of MgO barrier on Si is of technological importance due to the symmetry filtering effect of the MgO barrier in conjunction with bcc-ferromagnets. We study the epitaxial growth of MgO on (100)-Si by molecular beam epitaxy. MgO matches Si with 4:3 cell ratio, which renders Fe to be 45 deg. rotated relative to Si, in sharp contrast to the direct epitaxial growth of Fe on Si. The compressive strains from Si lead to the formation of small angle grain boundaries in MgO below 5 nm, and also affect the transport characteristics of Fe/MgO/Fe magnetic tunnel junctions formed on top.

Miao, G. X.; Veenhuizen, M. J. van; Moodera, J. S. [Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Chang, J. Y. [Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Center for Spintronics Research, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Thiel, K.; Seibt, M.; Eilers, G.; Muenzenberg, M. [IV.Physikalisches Institut, Universitaet Goettingen, Goettingen 37073 (Germany)

2008-10-06T23:59:59.000Z

244

Method and Apparatus for Concentrating Vapors for Analysis  

DOE Patents (OSTI)

An apparatus and method are disclosed for pre-concentrating gaseous vapors for analysis. The invention finds application in conjunction with, e.g., analytical instruments where low detection limits for gaseous vapors are desirable. Vapors sorbed and concentrated within the bed of the apparatus can be thermally desorbed achieving at least partial separation of vapor mixtures. The apparatus is suitable, e.g., for preconcentration and sample injection, and provides greater resolution of peaks for vapors within vapor mixtures, yielding detection levels that are 10-10,000 times better than for direct sampling and analysis systems. Features are particularly useful for continuous unattended monitoring applications.

Grate, Jay W. (West Richland, WA); Baldwin, David L. (Kennewick, WA); Anheier, Jr., Norman C. (Richland, WA)

2008-10-07T23:59:59.000Z

245

Gas phase 129Xe NMR imaging and spectroscopy  

E-Print Network (OSTI)

5 l l Dynamic NMR microscopy of gas phase Poiseuille flowmetal vapors and noble gases can be used to efficientlypolarize the nuclei ofthe noble-gas atoms. As a result, the

Kaiser, Lana G.

2010-01-01T23:59:59.000Z

246

Design of a microbreather for two-phase microchannel devices  

E-Print Network (OSTI)

Multiphase flows in microchannels are encountered in a variety of microfluidic applications. Two-phase microchannel heat sinks leverage the latent heat of vaporization to offer an efficient method of dissipating large heat ...

Alexander, Brentan R

2008-01-01T23:59:59.000Z

247

Micro and nanostructured surfaces for enhanced phase change heat transfer  

E-Print Network (OSTI)

Two-phase microchannel heat sinks are of significant interest for thermal management applications, where the latent heat of vaporization offers an efficient method to dissipate large heat fluxes in a compact device. However, ...

Chu, Kuang-Han, Ph. D. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

248

Electronic states in epitaxial graphene fabricated on silicon carbide  

SciTech Connect

An analytical expression for the density of states of a graphene monolayer interacting with a silicon carbide surface (epitaxial graphene) is derived. The density of states of silicon carbide is described within the Haldane-Anderson model. It is shown that the graphene-substrate interaction results in a narrow gap of {approx}0.01-0.06 eV in the density of states of graphene. The graphene atom charge is estimated; it is shown that the charge transfer from the substrate is {approx}10{sup -3}-10{sup -2}e per graphene atom.

Davydov, S. Yu., E-mail: Sergei_Davydov@mail.ru [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation)

2011-08-15T23:59:59.000Z

249

Graphene growth with giant domains using chemical vapor deposition  

E-Print Network (OSTI)

N. Martensson, Controlling graphene corrugation on lattice-in patterned epitaxial graphene, Science, 2006, 312(5777), 92009, 4(6), 17 A. K. Geim, Graphene: Status and Prospects,

Yong, Virginia; Hahn, H. Thomas

2011-01-01T23:59:59.000Z

250

Low Temperature Direct Growth of Graphene Films on Transparent Substrates by Chemical Vapor Deposition  

E-Print Network (OSTI)

and Few- Layer Graphene by Chemical Vapor Deposition",Liu, W. , et al. (2010). "Chemical vapor deposition of large5 1.3.3. Chemical Vapor

Antoine, Geoffrey Sandosh Jeffy

2013-01-01T23:59:59.000Z

251

Infrared phonon structure in epitaxial films of Tl sub 2 Ca sub 2 Ba sub 2 Cu sub 3 O sub 10 at low temperatures  

SciTech Connect

We have used both bolometric and cavity techniques to obtain accurate submillimeter and microwave loss data for epitaxial thin films of Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub 10} at low temperatures. These films have {Tc}=121.5 K, are c-axis oriented, contain some volume fraction of the 2:1:2:2 phase, and are characterized by excellent in-plane epitaxy. The absorptivity of these films at 100 cm{sup {minus}1} is a factor of five lower than that obtained by others from a reflectivity measurement on a ceramic sample. We observe strong phonon structure for frequencies between 70 and 600 cm{sup {minus}1}, which are in agreement with a lattice dynamical calculation. Our results show remarkably similar phonon structure to that observed in the ceramic sample. This is in strong contrast to the case for other high {Tc} superconductors such as YBa{sub 2}Cu{sub 3}O{sub 7}, where phonon structure observed in ceramic samples in absent in epitaxial oriented films and crystals because of the electronic screening due to the high conductivity of the a-b planes. At microwave frequencies the absorptivity follows a frequency squared dependence, and is consistent with the submillimeter results. 6 refs.

Miller, D.; Richards, P.L. (Lawrence Berkeley Lab., CA (United States)); Lee, W.Y. (IBM Research Div., San Jose, CA (United States). Almaden Research Center); Newman, N.; Garrison, S.M. (Conductus, Inc., Sunnyvale, CA (United States)); Martens, J.S. (Sandia National Labs., Albuquerque, NM (United States))

1992-02-01T23:59:59.000Z

252

Measurement of gas transport properties for chemical vapor infiltration  

Science Conference Proceedings (OSTI)

In the chemical vapor infiltration (CVI) process for fabricating ceramic matrix composites (CMCs), transport of gas phase reactant into the fiber preform is a critical step. The transport can be driven by pressure or by concentration. This report describes methods for measuring this for CVI preforms and partially infiltrated composites. Results are presented for Nicalon fiber cloth layup preforms and composites, Nextel fiber braid preforms and composites, and a Nicalon fiber 3-D weave composite. The results are consistent with a percolating network model for gas transport in CVI preforms and composites. This model predicts inherent variability in local pore characteristics and transport properties, and therefore, in local densification during processing; this may lead to production of gastight composites.

Starr, T.L.; Hablutzel, N. [Georgia Inst. of Tech., Atlanta, GA (United States). School of Materials Science and Engineering

1996-12-01T23:59:59.000Z

253

FFT-LB modeling of thermal liquid-vapor systems  

E-Print Network (OSTI)

We further develop a thermal LB model for multiphase flows. In the improved model, we propose to use the FFT scheme to calculate both the convection term and external force term. The usage of FFT scheme is detailed and analyzed. By using the FFT algorithm spatiotemporal discretization errors are decreased dramatically and the conservation of total energy is much better preserved. A direct consequence of the improvement is that the unphysical spurious velocities at the interfacial regions can be damped to neglectable scale. Together with the better conservation of total energy, the more accurate flow velocities lead to the more accurate temperature field which determines the dynamical and final states of the system. With the new model, the phase diagram of the liquid-vapor system obtained from simulation is more consistent with that from theoretical calculation. Very sharp interfaces can be achieved. The accuracy of simulation results are also verified by the Laplace law. The FFT scheme can be easily applied t...

Gan, Yanbiao; Zhang, Guangcai; Li, Yingjun

2012-01-01T23:59:59.000Z

254

Low Temperature Chemical Vapor Deposition Of Thin Film Magnets  

DOE Patents (OSTI)

A thin-film magnet formed from a gas-phase reaction of tetracyanoetheylene (TCNE) OR (TCNQ), 7,7,8,8-tetracyano-P-quinodimethane, and a vanadium-containing compound such as vanadium hexcarbonyl (V(CO).sub.6) and bis(benzene)vanalium (V(C.sub.6 H.sub.6).sub.2) and a process of forming a magnetic thin film upon at least one substrate by chemical vapor deposition (CVD) at a process temperature not exceeding approximately 90.degree. C. and in the absence of a solvent. The magnetic thin film is particularly suitable for being disposed upon rigid or flexible substrates at temperatures in the range of 40.degree. C. and 70.degree. C. The present invention exhibits air-stable characteristics and qualities and is particularly suitable for providing being disposed upon a wide variety of substrates.

Miller, Joel S. (Salt Lake City, UT); Pokhodnya, Kostyantyn I. (Salt Lake City, UT)

2003-12-09T23:59:59.000Z

255

Chemical vapor deposition of hydrogenated amorphous silicon from disilane  

SciTech Connect

The authors describe hydrogenated amorphous silicon (a-Si:H) thin films deposited at growth rates of 1 to 30 A/s by chemical vapor deposition (CVD) from disilane source gas at 24 torr total pressure in a tubular reactor. The effects of substrate temperature and gas holding time (flow rate) on film growth rate and effluent gas composition were measured at temperatures ranging from 360{sup 0} to 485{sup 0}C and gas holding times from 3 to 62s. Effluent gases determined by gas chromatography included silane, disilane and other higher order silanes. A chemical reaction engineering model, based on a silylene (SiH/sub 2/) insertion gas phase reaction network and film growth from both SiH/sub 2/ and high molecular weight silicon species, Si/sub n/H/sub 2n/, was developed. The model predictions were in good agreement with experimentally determined growth rates and effluent gas compositions.

Bogaert, R.J.; Russell, T.W.F.; Klein, M.T. (Delaware Univ., Newark, DE (USA). Dept. of Chemical Engineering); Rocheleau, R.E.; Baron, B.N. (Delaware Univ., Newark, DE (USA). Inst. of Energy Conversion)

1989-10-01T23:59:59.000Z

256

Profiling Atmospheric Water Vapor by Microwave Radiometry  

Science Conference Proceedings (OSTI)

High-altitude microwave radiometric observations at frequencies near 92 and 183.3 GHz were used to study the potential of retrieving atmospheric water vapor profiles over both land and water. An algorithm based on an extended Kaiman-Bucy filter ...

J. R. Wang; J. L. King; T. T. Wilheit; G. Szejwach; L. H. Gesell; R. A. Nieman; D. S. Niver; B. M. Krupp; J. A. Gagliano

1983-05-01T23:59:59.000Z

257

Polynomial Fits to Saturation Vapor Pressure  

Science Conference Proceedings (OSTI)

The authors describe eighth- and sixth-order polynomial fits to Wexler's and Hyland-Wexler's saturation-vapor-pressure expressions. Fits are provided in both least-squares and relative-error norms. Error analysis is presented. The authors show ...

Piotr J. Flatau; Robert L. Walko; William R. Cotton

1992-12-01T23:59:59.000Z

258

Chemical vapor deposition of mullite coatings  

DOE Patents (OSTI)

This invention is directed to the creation of crystalline mullite coatings having uniform microstructure by chemical vapor deposition (CVD). The process comprises the steps of establishing a flow of reactants which will yield mullite in a CVD reactor, and depositing a crystalline coating from the reactant flow. The process will yield crystalline coatings which are dense and of uniform thickness.

Sarin, Vinod (Lexington, MA); Mulpuri, Rao (Boston, MA)

1998-01-01T23:59:59.000Z

259

A Water Vapor Index from Satellite Measurements  

Science Conference Proceedings (OSTI)

A method for deriving a water vapor index is presented. An important feature of the index is the fact that it does not rely on radiosondes. Thus, it is not influenced by problems associated with radiosondes and the extent to which the horizontal ...

Larry M. McMillin; David S. Crosby; Mitchell D. Goldberg

1995-07-01T23:59:59.000Z

260

Microwave plasma chemical vapor deposition of nano-composite...  

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

plasma chemical vapor deposition of nano-composite CPt thin-films Title Microwave plasma chemical vapor deposition of nano-composite CPt thin-films Publication Type Journal...

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Microwave Plasma Chemical Vapor Depositon of Nano-Structured...  

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

Plasma Chemical Vapor Depositon of Nano-Structured SnC Composite Thin-Film anodes for Li-ion Battteries Title Microwave Plasma Chemical Vapor Depositon of Nano-Structured SnC...

262

The Effect of vapor subcooling on film condensation of metals  

E-Print Network (OSTI)

This work presents an analysis of the interfacial "vapor-condensate" temperature distribution, which includes the effect of subcooling (supersaturation) in the vapor. Experimental data from previous investigators for ...

Fedorovich, Eugene D.

1968-01-01T23:59:59.000Z

263

Waste tank headspace gas and vapor characterization reference guide  

SciTech Connect

This document is to serve as a reference guide for gas and vapor sample results presented in tank characterization reports. It describes sampling equipment, devices, and protocols, and sample collection and analysis methods common to all vapor samples.

Huckaby, J.L.

1995-06-01T23:59:59.000Z

264

Atmospheric Solar Heating Rate in the Water Vapor Bands  

Science Conference Proceedings (OSTI)

The total absorption of solar radiation by water vapor in clear atmosphere is parameterized as a simple function of the scaled water vapor amount. For applications to cloudy and hazy atmospheres, the flux-weighted k-distribution functions are ...

Ming-Dah Chou

1986-11-01T23:59:59.000Z

265

Estimating the Atmospheric Water Vapor Content from Sun Photometer Measurements  

Science Conference Proceedings (OSTI)

The differential absorption technique for estimating columnar water vapor values from the analysis of sunphotometric measurements with wide- and narrowband interferential filters centered near 0.94 ?m is discussed and adapted. Water vapor line ...

Artemio Plana-Fattori; Michel Legrand; Didier Tanré; Claude Devaux; Anne Vermeulen; Philippe Dubuisson

1998-08-01T23:59:59.000Z

266

Moisture Durability of Vapor Permeable Insulating Sheathing (Fact Sheet)  

SciTech Connect

In this project, Building America team Building Science Corporation researched some of the ramifications of using exterior, vapor permeable insulation on retrofit walls with vapor permeable cavity insulation. Retrofit strategies are a key factor in reducing exterior building stock consumption.

Not Available

2013-10-01T23:59:59.000Z

267

Improved Retrieval of Integrated Water Vapor from Water Vapor Radiometer Measurements Using Numerical Weather Prediction Models  

Science Conference Proceedings (OSTI)

Water vapor radiometer (WVR) retrieval algorithms require a priori information on atmospheric conditions along the line of sight of the radiometer in order to derive opacities from observed brightness temperatures. This paper's focus is the mean ...

Steven R. Chiswell; Steven Businger; Michael Bevis; Fredrick Solheim; Christian Rocken; Randolph Ware

1994-10-01T23:59:59.000Z

268

Optimal doping control of magnetic semiconductors via subsurfactant epitaxy  

SciTech Connect

Dilute magnetic semiconductors (DMS) with high ferromagnetic ordering temperatures (T{sub c}) have vast potential for advancing spin-based electronics or 'spintronics'. To date, achieving high-T{sub c} DMS typically required doping levels of order 5%. Such high doping levels inevitably compromise the structural homogeneity and carrier mobility of the DMS. Here, we establish 'subsurfactant epitaxy' as a novel kinetic pathway for synthesizing Mn-doped germanium with T{sub c} much higher than room temperature, at dramatically reduced doping levels. This is accomplished by optimal control of the diffusion kinetics of the dopant atoms near the growth front in two separate deposition steps. The first involves a submonolayer dose of Mn on Ge(100) at low temperature, which populates subsurface interstitial sites with Mn while suppressing lateral Mn diffusion and clustering. The second step involves epitaxial growth of Ge at elevated temperature, taking advantage of the strong floating ability of the interstitial Mn dopants towards the newly defined subsurface sites at the growth front. Most remarkably, the Mn dopants trapped inside the film are uniformly distributed at substitutional sites, and the resulting film exhibits ferromagnetism above 400 K at the nominal doping level of only 0.2%.

Zeng, Changgan [ORNL; Zhang, Zhenyu [ORNL; van Benthem, Klaus [ORNL; Chisholm, Matthew F [ORNL; Weitering, Harm H [ORNL

2008-01-01T23:59:59.000Z

269

Direct Evidence for the Suppression of Charge Stripes in Epitaxial {La1.67Sr0.33NiO4} Films  

Science Conference Proceedings (OSTI)

We have successfully grown epitaxial La1.67Sr0.33NiO4 films with a small crystalline mosaic using pulsed laser deposition. With synchrotron radiation, the x-ray-diffraction peaks associated with charge stripes have been successfully observed for relatively thick films. Anomalies due to the charge-ordering transition have been examined using four-point probe resistivity measurements. X-ray scattering provides direct evidence for suppression of the stripe phase in thinner samples; the phase disappears for film thicknesses 2600 Angstroms. The suppression appears to be a result of shrinking the stripe phase domains. This may reflect the stripe phase progressing from nematic to isotropic.

Xie,C.; Budnick, J.; Hines, W.; Wells, B.; He, F.; Moodenbaugh, A.

2008-01-01T23:59:59.000Z

270

Quantitative model of vapor dominated geothermal reservoirs as heat pipes in fractured porous rock  

DOE Green Energy (OSTI)

We present a numerical model of vapor-dominated reservoirs which is based on the well-known conceptual model of White, Muffler, and Truesdell. Computer simulations show that upon heat recharge at the base, a single phase liquid-dominated geothermal reservoir in fractured rock with low matrix permeability will evolve into a two-phase reservoir with B.P.D. (boiling point-for-depth) pressure and temperature profiles. A rather limited discharge event through cracks in the caprock, involving loss of only a few percent of fluids in place, is sufficient to set the system off to evolve a vapor-dominated state. The attributes of this state are discussed, and some features requiring further clarification are identified. 26 refs., 5 figs.

Pruess, K.

1985-03-01T23:59:59.000Z

271

Modeling engine oil vaporization and transport of the oil vapor in the piston ring pack on internal combustion engines  

E-Print Network (OSTI)

A model was developed to study engine oil vaporization and oil vapor transport in the piston ring pack of internal combustion engines. With the assumption that the multi-grade oil can be modeled as a compound of several ...

Cho, Yeunwoo, 1973-

2004-01-01T23:59:59.000Z

272

Metal film deposition by laser breakdown chemical vapor deposition  

Science Conference Proceedings (OSTI)

Dielectric breakdown of gas mixtures can be used to deposit homogeneous thin films by chemical vapor deposition with appropriate control of flow and pressure conditions to suppress gas phase nucleation and particle formation. Using a pulsed CO/sub 2/ laser operating at 10.6 microns where there is no significant resonant absorption in any of the source gases, we have succeeded in depositing homogeneous films from several gas phase precursors by gas phase laser pyrolysis. Nickel and molybdenum from the respective carbonyls and tungsten from the hexafluoride have been examined to date. In each case the gas precursor is buffered to reduce the partial pressure of the reactants and to induce breakdown. The films are spectrally reflective and uniform over a large area. Films have been characterized by Auger electron spectroscopy, x-ray diffraction, pull tests, and resistivity measurements. The highest quality films have resulted from the nickel depositions. Detailed x-ray diffraction analysis of these films yields a very small domain size (approx. 50 A) consistent with rapid quenching from the gas phase reaction zone. This analysis also shows nickel carbide formation consistent with the temperature of the reaction zone and the Auger electron spectroscopy results which show some carbon and oxygen incorporation (8% and 1% respectively). Gas phase transport and condensation of the molybdenum carbonyl results in substantial carbon and oxygen contamination of the molybdenum films requiring heated substrates, a requirement not consistent with the goals of the program to maximize the quench rate of the deposition. Results from tungsten deposition experiments representing a reduction chemistry instead of the decomposition chemistry involved in the carbonyl experiments are also reported.

Jervis, T.R.

1985-01-01T23:59:59.000Z

273

Monolayer Graphene Growth on Ni(111) by Low Temperature Chemical Vapor Deposition  

Science Conference Proceedings (OSTI)

In contrast to the commonly employed high temperature chemical vapor deposition growth that leads to multilayer graphene formation by carbon segregation from the bulk, we demonstrate that below 600 C graphene can be grown in a self-limiting monolayer growth process. Optimum growth is achieved at {approx}550 C. Above this temperature, carbon diffusion into the bulk is limiting the surface growth rate, while at temperatures below {approx}500 C a competing surface carbide phase impedes graphene formation.

Batzill, M.; Sutter, P.; Addou, R.; Dahal, A.

2012-01-09T23:59:59.000Z

274

Evaluation of selected chemical processes for production of low-cost silicon (Phase II). Silicon Material Task Low-Cost Silicon Solar Array Project. Eighth quarterly progress report, July 1, 1977--September 30, 1977. [Zinc vapor reduction of silicon tetrachloride in fluidized bed of seed particles  

DOE Green Energy (OSTI)

Progress is reported in the design of a large experimental facility for the preparation of high-purity silicon by the zinc vapor reduction of silicon tetrachloride in a fluidized bed of seed particles to form a free-flowing granular product. As of July 25, 1977, the capacity goal for the experimental facility was raised from 25 to 50 MT Si/year. Process flow diagrams and materials/energy flow sheets have been revised to conform to the higher capacity and a plant layout has been developed for locating the facility within an available structure. A unit-by-unit review of instrumentation and other requirements has been made, with the inclusion of those items in the flow diagrams and flow sheets. Alternative designs are presented for a silicon carbide-coated carbon-lined fluidized-bed reactor contained in hot-wall stainless steel, including alternative designs for zinc vaporizers based on detailed heat-transfer calculations. Conditions and equipment for the conversion of by-product chlorine to hypochlorite for use in the treatment of sewage effluent locally were defined. The logistics of 19 percent NaOH delivery and pick-up of 14 percent NaOCL was worked out and equipment suppliers were identified. Heat dissipation requirements for the fluidized bed, Zn/ZnCl/sub 2/ condenser, and SiCl/sub 4/ waste disposal sections were established. Resistivity and purity data were obtained for DuPont's silicon prepared by batchwise zinc reduction of SiCl/sub 4/. A preliminary safety review was made of the experimental facility. During the report period, the miniplant was operated to (1) provide 2.2 kg of product for JPL evaluation, (2) evaluate methods of product withdrawal, and (3) test three zinc vaporizer concepts. Results of the zinc vaporizer tests were consistent with concurrent heat-transfer calculations. An average value of approximately 450 Btu hr/sup -1/ ft/sup -2/ F/sup -1/ for heat transfer from graphite to boiling zinc (1 atm) was determined.

Blocher, J.M. Jr.; Browning, M.F.; Wilson, W.J.; Carmichael, D.C.

1977-10-20T23:59:59.000Z

275

Advanced Membrane Systems: Recovering Wasteful and Hazardous Fuel Vapors at the Gasoline Tank  

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

Case study covering Compact Membrane Systems, Inc. and its membrane vapor processor that recovers fuel vapors from gasoline refueling.

276

Epitaxial growth of metal fluoride thin films by pulsed-laser deposition  

SciTech Connect

We have studied growth of GdLiF4 thin films for optical waveguide applications. Epitaxial, c-axis oriented GdLiF4 films wer grown from undoped GdLiF4 targets in an on-axis Pulsed-laser deposition geometry on (100) CaF2. These films exhibit a high density of particulates on the surface which are ejected from the target in the ablation process. Growth from Nd-doped polycrystalline GdLiF4 ablation targets results in smooth films with lower particulate densities, as Nd doping increases the optical absorption of GdLiF4 at the ablation laser wavelength 193 nm and permits efficient pulsed-laser deposition. Optical emission spectra of the ablation pume reveals the presence of atomic F, Gd, and Li, indicating the dissociation of the metal-fluorine bonds in the ablation process. In addition, we find that the residual background oxygen pressure must be reduced to avoid formation of Gd4O3F6 as an impurity oxyfluoride phase in the films.

Norton, D.P.; Budal, J.D.; Chakoumakos, B.C.; Geohegan, D.B. [Oak Ridge National Lab., TN (United States); Puretzky, A. [AN SSSR, Troitsk (Russian Federation). Inst. Spektroskopii

1995-12-01T23:59:59.000Z

277

Vapor-pressure lowering in geothermal systems  

SciTech Connect

The water vapor-pressure lowering phenomenon in porous media was investigated for a range of temperatures by measuring vapor pressure vs. mass of water adsorbed in consolidated sandstone cores and unconsolidated silica sands. Experimental results showed that the mass of water adsorbed on the rock surface is much more than the amount of pore steam. Results also revealed that the water adsorption is caused mainly by micropores in the porous medium. Measurement of the mass of methane and ethane adsorbed on dry rocks showed that the amount of adsorption is not great in comparison with the pore gas. It was found that adsorption data for water/sandstone core studies could be normalized with respect to temperature. Although this appears not to have been reported previously, it does agree in principle with findings for solid powders with micropores. Another interesting result was that reanalysis of previous studies of capillarity in sandstones indicates that experimental data probably were influenced mostly by adsorption.

Hsieh, C.H.; Ramey, H.J. Jr.

1983-02-01T23:59:59.000Z

278

Hydrocarbon pool and vapor fire data analysis  

SciTech Connect

The flame geometry and thermal radiation data from a series of large scale experiments involving liquefied petroleum gas (LPG) and gasoline spills on water were analyzed. The experiments were conducted at the Naval Weapons Center, China Lake, California. Two types of fires have been studied; namely, pool fires and vapor fires. The spill quantity varied from 4 m/sup 3/ to approximately 6 m/sup 3/. The LPG pool fire flame height to diameter ratio were between 3.5 and 4.5. The gasoline flame height was about 2. The flame emissive powers for LPG pool fires ranged from 78 kW/m/sup 2/ to 115 kW/m/sup 2/. The average surface emissive power for gasoline pool fire was 40 kW/m/sup 2/. The LPG vapor fire emissive power ranged from 159 to 269 kW/m/sup 2/. 63 figures, 13 tables.

Mudan, K.S.

1984-10-01T23:59:59.000Z

279

Copper vapor laser modular packaging assembly  

DOE Patents (OSTI)

A modularized packaging arrangement for one or more copper vapor lasers and associated equipment is disclosed herein. This arrangement includes a single housing which contains the laser or lasers and all their associated equipment except power, water and neon, and means for bringing power, water, and neon which are necessary to the operation of the lasers into the container for use by the laser or lasers and their associated equipment.

Alger, Terry W. (Tracy, CA); Ault, Earl R. (Dublin, CA); Moses, Edward I. (Castro Valley, CA)

1992-01-01T23:59:59.000Z

280

Copper vapor laser modular packaging assembly  

DOE Patents (OSTI)

A modularized packaging arrangement for one or more copper vapor lasers and associated equipment is disclosed herein. This arrangement includes a single housing which contains the laser or lasers and all their associated equipment except power, water and neon, and means for bringing power, water, and neon which are necessary to the operation of the lasers into the container for use by the laser or lasers and their associated equipment. 2 figs.

Alger, T.W.; Ault, E.R.; Moses, E.I.

1992-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

DuPont Chemical Vapor Technical Report  

Science Conference Proceedings (OSTI)

DuPont Safety Resources was tasked with reviewing the current chemical vapor control practices and providing preventive recommendations on best commercial techniques to control worker exposures. The increased focus of the tank closure project to meet the 2024 Tri-Party Agreement (TPA) milestones has surfaced concerns among some CH2MHill employees and other interested parties. CH2MHill is committed to providing a safe working environment for employees and desires to safely manage the tank farm operations using appropriate control measures. To address worker concerns, CH2MHill has chartered a ''Chemical Vapors Project'' to integrate the activities of multiple CH2MHill project teams, and solicit the expertise of external resources, including an independent Industrial Hygiene expert panel, a communications consultant, and DuPont Safety Resources. Over a three-month time period, DuPont worked with CH2MHill ESH&Q, Industrial Hygiene, Engineering, and the independent expert panel to perform the assessment. The process included overview presentations, formal interviews, informal discussions, documentation review, and literature review. DuPont Safety Resources concluded that it is highly unlikely that workers in the tank farms are exposed to chemicals above established standards. Additionally, the conventional and radiological chemistry is understood, the inherent chemical hazards are known, and the risk associated with chemical vapor exposure is properly managed. The assessment highlighted management's commitment to addressing chemical vapor hazards and controlling the associated risks. Additionally, we found the Industrial Hygiene staff to be technically competent and well motivated. The tank characterization data resides in a comprehensive database containing the tank chemical compositions and relevant airborne concentrations.

MOORE, T.L.

2003-10-03T23:59:59.000Z

282

OPERATIONAL TESTS OF EBWR VAPOR RECOVERY SYSTEM  

SciTech Connect

A description of the Experimental Boiling Water Reactor vapor-recovery system is given. The seal air operating pressures, temperatures, and moisture content were measured. Air flow through the seals was measured and seal wear was assessed. Assuming direct-cycle D/sub 2/ operation, the seals were evaluated relative to the amount of D/sub 2/ leakage that would be controlled (C.J.G.)

Gariboldi, R.J.; Jacobson, D.R.

1960-08-01T23:59:59.000Z

283

Transport properties of fission product vapors  

DOE Green Energy (OSTI)

Kinetic theory of gases is used to calculate the transport properties of fission product vapors in a steam and hydrogen environment. Provided in tabular form is diffusivity of steam and hydrogen, viscosity and thermal conductivity of the gaseous mixture, and diffusivity of cesium iodide, cesium hydroxide, diatomic tellurium and tellurium dioxide. These transport properties are required in determining the thermal-hydraulics of and fission product transport in light water reactors.

Im, K.H.; Ahluwalia, R.K.

1983-07-01T23:59:59.000Z

284

Apparatus and method for photochemical vapor deposition  

DOE Patents (OSTI)

A photochemical vapor deposition apparatus includes a reactor housing having a window in one wall above a reaction chamber in the housing. A transparent curtain divides the reaction chamber into a reaction zone and a flush zone. At least one substrate is mounted in the reaction zone in light communication with the window so that ultraviolet radiation may penetrate through the window into the reaction zone. The window is kept clear by a gas flowing through the flush zone.

Jackson, Scott C. (Wilmington, DE); Rocheleau, Richard E. (Wilmington, DE)

1987-03-31T23:59:59.000Z

285

Passive vapor transport solar heating systems  

DOE Green Energy (OSTI)

In the systems under consideration, refrigerant is evaporated in a solar collector and condensed in thermal storage for space or water heating located within the building at a level below that of the collector. Condensed liquid is lifted to an accumulator above the collector by the vapor pressure generated in the collector. Tests of two systems are described, and it is concluded that one of these systems offers distinct advantages.

Hedstrom, J.C.; Neeper, D.A.

1985-01-01T23:59:59.000Z

286

A molecular view of vapor deposited glasses  

SciTech Connect

Recently, novel organic glassy materials that exhibit remarkable stability have been prepared by vapor deposition. The thermophysical properties of these new ''stable'' glasses are equivalent to those that common glasses would exhibit after aging over periods lasting thousands of years. The origin of such enhanced stability has been elusive; in the absence of detailed models, past studies have discussed the formation of new polyamorphs or that of nanocrystals to explain the observed behavior. In this work, an atomistic molecular model of trehalose, a disaccharide of glucose, is used to examine the properties of vapor-deposited stable glasses. Consistent with experiment, the model predicts the formation of stable glasses having a higher density, a lower enthalpy, and higher onset temperatures than those of the corresponding ''ordinary'' glass formed by quenching the bulk liquid. Simulations reveal that newly formed layers of the growing vapor-deposited film exhibit greater mobility than the remainder of the material, thereby enabling a reorganization of the film as it is grown. They also reveal that ''stable'' glasses exhibit a distinct layered structure in the direction normal to the substrate that is responsible for their unusual properties.

Singh, Sadanand; Pablo, Juan J. de [Department of Chemical and Biological Engineering, University of Wisconsin, Madison Wisconsin 53706 (United States)

2011-05-21T23:59:59.000Z

287

Heat storage system utilizing phase change materials government rights  

DOE Patents (OSTI)

A thermal energy transport and storage system is provided which includes an evaporator containing a mixture of a first phase change material and a silica powder, and a condenser containing a second phase change material. The silica powder/PCM mixture absorbs heat energy from a source such as a solar collector such that the phase change material forms a vapor which is transported from the evaporator to the condenser, where the second phase change material melts and stores the heat energy, then releases the energy to an environmental space via a heat exchanger. The vapor is condensed to a liquid which is transported back to the evaporator. The system allows the repeated transfer of thermal energy using the heat of vaporization and condensation of the phase change material.

Salyer, Ival O. (Dayton, OH)

2000-09-12T23:59:59.000Z

288

Three-fold diffraction symmetry in epitaxial graphene and the SiC substrate  

E-Print Network (OSTI)

Epitaxial Graphene and the SiC Substrate D.A. Siegel, 1, 2in graphene ?lms on 6H-SiC(0001) have been studied by lowgrown on the C face of SiC (which possesses azimuthal

Siegel, D A

2010-01-01T23:59:59.000Z

289

Epitaxial Ge/Il-V Heterostructures : MOCVD growth, characterization, and applications  

E-Print Network (OSTI)

Epitaxial Ge thin films are being investigated for many important roles in next generation microelectronics. Metal-oxide-semiconductor field effect transistors (MOSFETs) utilizing Ge channels have demonstrated dramatic ...

Bai, Yu, Ph.D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

290

Understanding controls on interfacial wetting at epitaxial graphene: Experiment and Theory  

SciTech Connect

The interaction of interfacial water with graphitic carbon at the atomic scale is studied as a function of the hydrophobicity of epitaxial graphene. High resolution x-ray reflectivity shows that the graphene-water contact angle is controlled by the average graphene thickness, due to the fraction of the film surface expressed as the epitaxial buffer layer whose contact angle (contact angle c = 73 ) is substantially smaller than that of multilayer graphene ( c = 93 ). Classical and ab initio molecular dynamics simulations show that the reduced contact angle of the buffer layer is due to both its epitaxy with the SiC substrate and the presence of interfacial defects. This insight clarifies the relationship between interfacial water structure and hydrophobicity, in general, and suggests new routes to control interface properties of epitaxial graphene.

Zhou, Hua [Argonne National Laboratory (ANL); Ganesh, Panchapakesan [ORNL; Presser, Volker [Drexel University; Wander, Matthew C [ORNL; Fenter, Paul [Argonne National Laboratory (ANL); Kent, Paul R [ORNL; Jiang, Deen [ORNL; Chialvo, Ariel A [ORNL; Mcdonough, John [Drexel University; Shuford, Kevin L [ORNL; Gogotsi, Yury G. [Drexel University

2012-01-01T23:59:59.000Z

291

Epitaxial VN,,001... Grown and Analyzed In situ by XPS and UPS. II. Analysis of Ar  

E-Print Network (OSTI)

Epitaxial VN,,001... Grown and Analyzed In situ by XPS and UPS. II. Analysis of Ar¿ Sputter Etched-welded to a Mo substrate heater. In Situ Preparation: The epitaxial VN 001 layers were grown in a multichamber that has been shown Ref. 1 to produce sharp 1 1 RHEED patterns. The target, a 5-cm-diam water-cooled V disk

Gall, Daniel

292

High-quality epitaxial CoFe/Si(111) heterostructures fabricated by low-temperature molecular beam epitaxy  

SciTech Connect

We demonstrate atomically controlled heterojunctions consisting of ferromagnetic CoFe alloys and silicon (Si) using low-temperature molecular beam epitaxy with a good atomic matching at the (111) plane. The saturation magnetization of the CoFe layers grown reaches {approx}85% of the value of bulk samples reported so far, and can be systematically controlled by tuning the ratio of Co to Fe, indicating that the silicidation reactions between CoFe and Si are suppressed and the heterojunctions are very high quality. We find that the Schottky barrier height of the high-quality CoFe/Si(111) junctions is unexpectedly low compared to the previous data for other metal/Si ones, implying the reduction in the Fermi-level-pinning effect. We can expand the available high-quality ferromagnet/Si heterostructures in the field of Si-based spintronics.

Maeda, Y.; Yamada, S.; Ando, Y.; Yamane, K.; Miyao, M. [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Hamaya, K. [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); PRESTO, Japan Science and Technology Agency, Sanbancho, Tokyo 102-0075 (Japan)

2010-11-08T23:59:59.000Z

293

A comparison of diamond growth rate using in-liquid and conventional plasma chemical vapor deposition methods  

Science Conference Proceedings (OSTI)

In order to make high-speed deposition of diamond effective, diamond growth rates for gas-phase microwave plasma chemical vapor deposition and in-liquid microwave plasma chemical vapor deposition are compared. A mixed gas of methane and hydrogen is used as the source gas for the gas-phase deposition, and a methanol solution of ethanol is used as the source liquid for the in-liquid deposition. The experimental system pressure is in the range of 60-150 kPa. While the growth rate of diamond increases as the pressure increases, the amount of input microwave energy per unit volume of diamond is 1 kW h/mm{sup 3} regardless of the method used. Since the in-liquid deposition method provides a superior cooling effect through the evaporation of the liquid itself, a higher electric input power can be applied to the electrodes under higher pressure environments. The growth rate of in-liquid microwave plasma chemical vapor deposition process is found to be greater than conventional gas-phase microwave plasma chemical vapor deposition process under the same pressure conditions.

Takahashi, Yoshiyuki; Toyota, Hiromichi; Nomura, Shinfuku; Mukasa, Shinobu [Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama 790-8577 (Japan); Inoue, Toru [Geodynamics Research Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)

2009-06-01T23:59:59.000Z

294

Liquid phase epitaxial growth and characterization of germanium far infrared blocked impurity band detectors  

E-Print Network (OSTI)

can be a thin layer of indium tin oxide sputtered onto theis Sn-doped In 2 0 3 (Indium Tin Oxide or ITO) which is an

Bandaru, Jordana

2001-01-01T23:59:59.000Z

295

Development of (Re)BaCuO Coated Conductors by Liquid Phase Epitaxy  

E-Print Network (OSTI)

higher Birr and potential savings in cryogen consumption costs and reducing the design complexity of cryogenic system. 2.4.1 Power generator and electric motor HTS generators and motors have the advantages of higher power density, higher efficiency... .3.5 Irreversibility line 15 2.4 Electric Power Applications of HTS 16 2.4.1 Power generator and electric motor 16 2.4.2 Energy storage 16 2.4.3 Electrical transmission and distribution 17 2.5 Summary 18 References 18 Chapter III Crystal Growth...

Cheng, Yee Siau

296

Vapor port and groundwater sampling well  

DOE Patents (OSTI)

A method and apparatus have been developed for combining groundwater monitoring wells with unsaturated-zone vapor sampling ports. The apparatus allows concurrent monitoring of both the unsaturated and the saturated zone from the same well at contaminated areas. The innovative well design allows for concurrent sampling of groundwater and volatile organic compounds (VOCs) in the vadose (unsaturated) zone from a single well, saving considerable time and money. The sample tubes are banded to the outer well casing during installation of the well casing. 10 figs.

Hubbell, J.M.; Wylie, A.H.

1996-01-09T23:59:59.000Z

297

Vapor port and groundwater sampling well  

DOE Patents (OSTI)

A method and apparatus has been developed for combining groundwater monitoring wells with unsaturated-zone vapor sampling ports. The apparatus allows concurrent monitoring of both the unsaturated and the saturated zone from the same well at contaminated areas. The innovative well design allows for concurrent sampling of groundwater and volatile organic compounds (VOCs) in the vadose (unsaturated) zone from a single well, saving considerable time and money. The sample tubes are banded to the outer well casing during installation of the well casing.

Hubbell, Joel M. (Idaho Falls, ID); Wylie, Allan H. (Idaho Falls, ID)

1996-01-01T23:59:59.000Z

298

Copper vapor laser acoustic thermometry system  

DOE Patents (OSTI)

A copper vapor laser (CVL) acoustic thermometry system is disclosed. The invention couples an acoustic pulse a predetermined distance into a laser tube by means of a transducer and an alumina rod such that an echo pulse is returned along the alumina rod to the point of entry. The time differential between the point of entry of the acoustic pulse into the laser tube and the exit of the echo pulse is related to the temperature at the predetermined distance within the laser tube. This information is processed and can provide an accurate indication of the average temperature within the laser tube.

Galkowski, J.J.

1986-08-27T23:59:59.000Z

299

Photochemical studies of alkali halide vapors  

SciTech Connect

Thesis. An apparatus has been constructed for studying the photodissociation of alkali halides to produce excited alkali metal atoms. The key component is a low pressure H/sub 2/ arc continuum uv source. Radiation from this source, modulated by a chopping wheel and analyzed by a monochromator, enters a cell containing the alkali halide vapor. In the appropriate wavelength range, photodissociation occurs to produce the alkali atom in an excited /sup 2/p state, the flourescence from which is detected by a photomultiplier-lock-in amplifier combination. (auth)

Earl, B.L.

1973-08-01T23:59:59.000Z

300

ARM - Field Campaign - Fall 1997 Water Vapor IOP  

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

Water Vapor IOP Water Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Fall 1997 Water Vapor IOP 1997.09.15 - 1997.10.05 Lead Scientist : Henry Revercomb For data sets, see below. Summary The Water Vapor IOP was conducted as a follow-up to a predecessor IOP on water vapor held in September 1996. This IOP relied heavily on both ground-based guest and CART instrumentation and in-situ aircraft and tethered sonde/kite measurements. Primary operational hours were from 6 p.m. Central until at least midnight, with aircraft support normally from about 9 p.m. until midnight when available. However, many daytime measurements were made to support this IOP. The first Water Vapor IOP primarily concentrated on the atmosphere's lowest

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Analysis of the transient compressible vapor flow in heat pipe  

SciTech Connect

The transient compressible one-dimensional vapor flow dynamics in a heat pipe is modeled. The numerical results are obtained by using the implicit non-iterative Beam-Warming finite difference method. The model is tested for simulated heat pipe vapor flow and actual vapor flow in cylindrical heat pipes. A good comparison of the present transient results for the simulated heat pipe vapor flow with the previous results of a two-dimensional numerical model is achieved and the steady state results are in agreement with the existing experimental data. The transient behavior of the vapor flow under subsonic, sonic, and supersonic speeds and high mass flow rates are successfully predicted. The one-dimensional model also describes the vapor flow dynamics in cylindrical heat pipes at high temperatures.

Jang, J.H.; Faghri, A. [Wright State Univ., Dayton, OH (United States); Chang, W.S. [Wright Research and Development Center, Wright-Patterson, OH (United States)

1989-07-01T23:59:59.000Z

302

Method and apparatus for concentrating vapors for analysis  

DOE Patents (OSTI)

A pre-concentration device and a method are disclosed for concentrating gaseous vapors for analysis. Vapors sorbed and concentrated within the bed of the pre-concentration device are thermally desorbed, achieving at least partial separation of the vapor mixtures. The pre-concentration device is suitable, e.g., for pre-concentration and sample injection, and provides greater resolution of peaks for vapors within vapor mixtures, yielding detection levels that are 10-10,000 times better than direct sampling and analysis systems. Features are particularly useful for continuous unattended monitoring applications. The invention finds application in conjunction with, e.g., analytical instruments where low detection limits for gaseous vapors are desirable.

Grate, Jay W. (West Richland, WA); Baldwin, David L. (Kennewick, WA); Anheier, Jr., Norman C. (Richland, WA)

2012-06-05T23:59:59.000Z

303

Phase Stability, Phase Transformations, and Reactive Phase ...  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... New Phase in Stoichiometric Cu6Sn5 and Effect of Ni Addition on Phase Stabilization in Wide Temperature Range · Optical Properties of ...

304

Effects of capillary heterogeneity on vapor-liquid counterflow in porous media  

DOE Green Energy (OSTI)

Based on a continuum description, the effect of capillary heterogeneity, induced by variation in permeability, on the steady state, countercurrent, vapor-liquid flow in porous media is analyzed. It is shown that the heterogeneity acts as a body force, that may enhance or diminish gravity effects on heat pipes. Selection rules that determine the steady states reached in homogeneous, gravity-driven heat pipes are also formulated. It is shown that the ``infinite`` two-phase zone may terminate by a substantial change in the permeability somewhere in the medium. The two possible sequences, liquid - liquid dominated - dry, or liquid - vapor dominated - dry find applications in geothermal systems. Finally, it is shown that although weak heterogeneity affects only gravity controlled flows, stronger variations in permeability can give rise to significant capillary effects.

Stubos, A.K.; Satik, C.; Yortsos, Y.C.

1992-06-01T23:59:59.000Z

305

Effects of capillary heterogeneity on vapor-liquid counterflow in porous media  

DOE Green Energy (OSTI)

Based on a continuum description, the effect of capillary heterogeneity, induced by variation in permeability, on the steady state, countercurrent, vapor-liquid flow in porous media is analyzed. It is shown that the heterogeneity acts as a body force, that may enhance or diminish gravity effects on heat pipes. Selection rules that determine the steady states reached in homogeneous, gravity-driven heat pipes are also formulated. It is shown that the infinite'' two-phase zone may terminate by a substantial change in the permeability somewhere in the medium. The two possible sequences, liquid - liquid dominated - dry, or liquid - vapor dominated - dry find applications in geothermal systems. Finally, it is shown that although weak heterogeneity affects only gravity controlled flows, stronger variations in permeability can give rise to significant capillary effects.

Stubos, A.K.; Satik, C.; Yortsos, Y.C.

1992-06-01T23:59:59.000Z

306

Method for controlling corrosion in thermal vapor injection gases  

DOE Patents (OSTI)

An improvement in the method for producing high pressure thermal vapor streams from combustion gases for injection into subterranean oil producing formations to stimulate the production of viscous minerals is described. The improvement involves controlling corrosion in such thermal vapor gases by injecting water near the flame in the combustion zone and injecting ammonia into a vapor producing vessel to contact the combustion gases exiting the combustion chamber.

Sperry, John S. (Houston, TX); Krajicek, Richard W. (Houston, TX)

1981-01-01T23:59:59.000Z

307

Water injection as a means for reducing non-condensible andcorrosive gases in steam produced from vapor-dominated reservoirs  

Science Conference Proceedings (OSTI)

Large-scale water injection at The Geysers, California, hasgenerated substantial benefits in terms of sustaining reservoir pressuresand production rates, as well as improving steam composition by reducingthe content of non-condensible gases (NCGs). Two effects have beenrecognized and discussed in the literature as contributing to improvedsteam composition, (1) boiling of injectate provides a source of "clean"steam to production wells, and (2) pressurization effects induced byboiling of injected water reduce upflow of native steam with large NCGconcentrations from depth. In this paper we focus on a possibleadditional effect that could reduce NCGs in produced steam by dissolutionin a condensed aqueous phase.Boiling of injectate causes pressurizationeffects that will fairly rapidly migrate outward, away from the injectionpoint. Pressure increases will cause an increase in the saturation ofcondensed phase due to vapor adsorption on mineral surfaces, andcapillary condensation in small pores. NCGs will dissolve in theadditional condensed phase which, depending upon their solubility, mayreduce NCG concentrations in residual steam.We have analyzed thepartitioning of HCl between vapor and aqueous phases, and have performednumerical simulations of injection into superheated vapor zones. Oursimulations provide evidence that dissolution in the condensed phase canindeed reduce NCG concentrations in produced steam.

Pruess, Karsten; Spycher, Nicolas; Kneafsey, Timothy J.

2007-01-08T23:59:59.000Z

308

Si(001):B gas-source molecular-beam epitaxy: Boron surface segregation and its effect on film growth kinetics  

E-Print Network (OSTI)

The use of disilane (Si2H6) rather than silane (SiH4) for Si 001 gas-source molecular-beam epitaxy GS

Spila, Timothy P.

309

A ghost fluid method for compressible reacting flows with phase change  

Science Conference Proceedings (OSTI)

A modified interfacial Riemann problem accounting for phase change and surface tension was developed to couple a reacting gas to a vaporizing compressible liquid. Results from the proposed numerical method compare well with empirically measured separation ... Keywords: Chemically reacting flow, Compressible multiphase flow, Ghost fluid method, Level set method, Navier-Stokes equations, Vaporization

Ryan W. Houim; Kenneth K. Kuo

2013-02-01T23:59:59.000Z

310

Phase Diagrams  

Science Conference Proceedings (OSTI)

Mar 7, 2013 ... Computational Thermodynamics and Kinetics: Phase Diagrams ... TMS: Alloy Phases Committee, TMS: Chemistry and Physics of Materials ...

311

Mercury Vapor At Lassen Volcanic National Park Area (Varekamp...  

Open Energy Info (EERE)

Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Mercury Vapor At Lassen Volcanic National Park Area (Varekamp & Buseck, 1983) Jump to:...

312

Mercury Vapor At Mickey Hot Springs Area (Varekamp & Buseck,...  

Open Energy Info (EERE)

Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Mercury Vapor At Mickey Hot Springs Area (Varekamp & Buseck, 1983) Jump to: navigation,...

313

Mercury Vapor At Breitenbush Hot Springs Area (Varekamp & Buseck...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Breitenbush Hot Springs Area (Varekamp & Buseck, 1983) Exploration Activity...

314

Mercury Vapor At Vale Hot Springs Area (Varekamp & Buseck, 1983...  

Open Energy Info (EERE)

Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Mercury Vapor At Vale Hot Springs Area (Varekamp & Buseck, 1983) Jump to: navigation, search...

315

Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) | Open Energy  

Open Energy Info (EERE)

Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Exploration Activity Details Location Haleakala Volcano Area Exploration Technique Mercury Vapor Activity Date Usefulness not indicated DOE-funding Unknown Notes The field survey program on the northwest rift zone consisted of soil mercury and radon emanometry surveys, groundwater temperature and chemistry studies, Schlumberger resistivity soundings and self-potential profiles. Geophysical and geochemical surveys along this rift (southwest) were limited by difficult field conditions and access limitations. The geophysical program consisted of one Schlumberger sounding, one

316

Measurements of Vapor Pressures and PVT Properties for n ...  

Science Conference Proceedings (OSTI)

Page 1. Measurements of Vapor Pressures and PVT Properties for n-Butane from 280 to 440 K at Pressures to 200 MPa ...

2006-07-20T23:59:59.000Z

317

Interaction of sodium vapor and graphite studied by ...  

Science Conference Proceedings (OSTI)

The kinetics of the reaction between graphite and sodium vapor is analyzed with support ... High temperature compression test to determine the anode paste ...

318

Optimal Control of Vapor Extraction of Heavy Oil.  

E-Print Network (OSTI)

??Vapor extraction (Vapex) process is an emerging technology for viscous oil recovery that has gained much attention in the oil industry. However, the oil production… (more)

Muhamad, Hameed

2012-01-01T23:59:59.000Z

319

ARM - Field Campaign - ARM-FIRE Water Vapor Experiment  

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

Order Data Browell, Edward LASE Order Data Gutman, Seth GPS Order Data Richardson, Scott Chilled Mirror Order Data Sachse, G. Water Vapor Order Data Schmidlin, Francis CM Sondes...

320

Molecular restrictions for human eye irritation by chemical vapors  

E-Print Network (OSTI)

and reactive airborne chemicals. Pharmacol. Toxicol. 1998;WL. Chemesthesis: The Common Chemical Sense. In: Finger TE,MH. Quantification of chemical vapors in chemosensory

Cometto-Muniz, J. Enrique; Cain, William S.; Abraham, Michael H.

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Raman Lidar Measurements of Aerosols and Water Vapor During the...  

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

Raman Lidar Measurements of Aerosols and Water Vapor During the May 2003 Aerosol IOP R. A. Ferrare National Aeronautics and Space Administration Langley Research Center Hampton,...

322

Cesium vapor cycle for an advanced LMFBR  

SciTech Connect

A review indicates that a cesium vapor topping cycle appears attractive for use in the intermediate fluid circuit of an advanced LMFBR designed for a reactor outlet temperature of 1250$sup 0$F or more and would have the following advantages: (1) it would increase the thermal efficiency by about 5 to 10 points (from approximately 40 percent to approximately 45 to 50 percent) thus reducing the amount of waste heat rejected to the environment by 15 to 30 percent. (2) the higher thermal efficiency should reduce the overall capital cost of the reactor plant in dollars per kilowatt. (3) the cesium can be distilled out of the intermediate fluid circuit to leave it bone-dry, thus greatly reducing the time and cost of maintenance work (particularly for the steam generator). (4) the large volume and low pressure of the cesium vapor region in the cesium condenser-steam generator greatly reduces the magnitude of pressure fluctuations that might occur in the event of a leak in a steam generator tube, and the characteristics inherent in a condenser make it easy to design for rapid concentration of any noncondensibles that may form as a consequence of a steam leak into the cesium region so that a steam leak can be detected easily in the very early stages of its development. (auth)

Fraas, A.P.

1975-01-01T23:59:59.000Z

323

Reactions of atmospheric vapors with lunar soil  

SciTech Connect

Detailed experimental data have been acquired for the hydration of the surfaces of lunar fines. Inert vapor adsorption has been employed to measure the surface properties (surface energy, surface area, porosity, etc.) and changes wrought in the hydration-dehydration processes. Plausible mechanisms have been considered and the predominant process involves hydration of the metamict metallosilicate surfaces to form a hydrated laminar structure akin to terrestrial clays. Additional credence for this interpretation is obtained by comparison to existing geochemical literature concerning terrestrial weathering of primary metallosilicates. The surface properties of the hydrated lunar fines are compared favorably to those of terrestrial clay minerals. In addition, experimental results are given to show that fresh disordered surfaces of volcanic sand react with water vapor in a manner virtually identical to the majority of the lunar fines. The results show that ion track etching and/or grain boundary attack are minor contributions in the weathering of lunar fines in the realm of our microgravimetric experimental conditions. 14 references. (auth)

Fuller, E.L. Jr.; Agron, P.A.

1976-03-01T23:59:59.000Z

324

Integration of Global Positioning System and Scanning Water Vapor Radiometers for Precipitable Water Vapor and Cloud Liquid Path Estimates  

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

Integration of Global Positioning System and Scanning Integration of Global Positioning System and Scanning Water Vapor Radiometers for Precipitable Water Vapor and Cloud Liquid Path Estimates V. Mattioli and P. Basili Department of Electronic and Information Engineering University of Perugia Perugia, Italy E. R. Westwater Cooperative Institute for Research in Environmental Sciences University of Colorado National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado Introduction In recent years the Global Positioning System (GPS) has proved to be a reliable instrument for measuring precipitable water vapor (PWV) (Bevis et al. 1992), offering an independent source of information on water vapor when compared with microwave radiometers (MWRs), and/or radiosonde

325

Vapor and gas sampling of Single-Shell Tank 241-A-101 using the Vapor Sampling System  

Science Conference Proceedings (OSTI)

This document presents sampling data resulting from the June 8, 1995, sampling of SST 241-A-101 using the Vapor Sampling System.

Caprio, G.S.

1995-11-01T23:59:59.000Z

326

Vapor and gas sampling of single-shell tank 241-SX-106 using the vapor sampling system  

SciTech Connect

This document presents sampling data resulting from the March 24, 1995, sampling of SST 241-SX-106 using the vapor sampling system.

Caprio, G.S.

1995-09-20T23:59:59.000Z

327

Low temperature epitaxial growth of Ge on cube- textured Ni  

SciTech Connect

Quasi- single crystal Ge films were grown on [001]<010> textured Ni substrate at a temperature of 350 oC using an insulating buffer layer of CaF2. A direct deposition of Ge on Ni at 350 oC was shown to alloy with Ni. From x- ray pole figure analysis, it was shown that Ge grew epitaxially with the same orientation as CaF2 and the dispersions in the out- of- plane and in- plane directions were found to be 1.7 0.1o and 6 1o, respectively. In the out- of- plane direction, Ge[111]||CaF2[111]||Ni[001]. In addition, the Ge consisted of four equivalent in- plane oriented domains such that two mutually orthogonal directions: Ge 211 and Ge 011 are parallel to mutually orthogonal directions: Ni 110 and Ni 110 , respectively of the Ni(001) surface. This was shown to be originated from the four equivalent in- plane oriented domains of CaF2 created to minimize the mismatch strain between CaF2 and Ni in those directions.

GIARE, C [Rensselaer Polytechnic Institute (RPI); Palazzo, J [Rensselaer Polytechnic Institute (RPI); Goyal, Amit [ORNL; WANG, G [Rensselaer Polytechnic Institute (RPI); LU, T [Rensselaer Polytechnic Institute (RPI)

2012-01-01T23:59:59.000Z

328

Chemically homogeneous and thermally reversible oxidation of epitaxial graphene  

Science Conference Proceedings (OSTI)

With its exceptional charge mobility, graphene holds great promise for applications in next-generation electronics. In an effort to tailor its properties and interfacial characteristics, the chemical functionalization of graphene is being actively pursued. The oxidation of graphene via the Hummers method is most widely used in current studies, although the chemical inhomogeneity and irreversibility of the resulting graphene oxide compromises its use in high-performance devices. Here, we present an alternative approach for oxidizing epitaxial graphene using atomic oxygen in ultrahigh vacuum. Atomic-resolution characterization with scanning tunnelling microscopy is quantitatively compared to density functional theory, showing that ultrahigh-vacuum oxidization results in uniform epoxy functionalization. Furthermore, this oxidation is shown to be fully reversible at temperatures as low as 260 8C using scanning tunnelling microscopy and spectroscopic techniques. In this manner, ultrahigh-vacuum oxidation overcomes the limitations of Hummers-method graphene oxide, thus creating new opportunities for the study and application of chemically functionalized graphene.

Hossain, Md. Zakir [Northwestern University, Evanston; Johns, James E. [Northwestern University, Evanston; Bevan, Kirk H [ORNL; Karmel, Hunter J. [Northwestern University, Evanston; Liang, Yu Teng [Northwestern University, Evanston; Yoshimoto, Shinya [University of Tokyo, Tokyo, Japan; Mukai, Kozo [University of Tokyo, Tokyo, Japan; Koitaya, Tatanori [University of Tokyo, Tokyo, Japan; Yoshinobu, Jun [University of Tokyo, Tokyo, Japan; Kawai, Maki [University of Tokyo, Tokyo, Japan; Lear, Amanda M. [Indiana University; Kesmodel, Larry L. [Indiana University; Tait, Steven L. [Indiana University; Hersam, Mark C. [Northwestern University, Evanston

2012-01-01T23:59:59.000Z

329

Formation behavior of Be{sub x}Zn{sub 1-x}O alloys grown by plasma-assisted molecular beam epitaxy  

SciTech Connect

We report the phase formation behavior of Be{sub x}Zn{sub 1-x}O alloys grown by plasma-assisted molecular beam epitaxy. We find the alloy with low- and high-Be contents could be obtained by alloying BeO into ZnO films. X-ray diffraction measurements shows the c lattice constant value shrinks, and room temperature absorption shows the energy band-gap widens after Be incorporated. However, the alloy with intermediate Be composition are unstable and segregated into low- and high-Be contents BeZnO alloys. We demonstrate the phase segregation of Be{sub x}Zn{sub 1-x}O alloys with intermediate Be composition resulted from large internal strain induced by large lattice mismatch between BeO and ZnO.

Chen, Mingming; Zhu, Yuan; Su, Longxing; Zhang, Quanlin; Chen, Anqi; Ji, Xu; Xiang, Rong; Gui, Xuchun; Wu, Tianzhun [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China)] [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Pan, Bicai [Department of Physics and Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China)] [Department of Physics and Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China); Tang, Zikang [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China) [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)

2013-05-20T23:59:59.000Z

330

Phase transitions in nanoscale ferroelectric structures.  

Science Conference Proceedings (OSTI)

Over decades of effort, investigations of the intrinsic phase transition behavior of nanoscale ferroelectric structures have been greatly complicated by materials processing variations and by the common and uncontrolled occurrence of spacecharge, which interacts directly with the polarization and can obscure fundamental behavior. These challenges have largely been overcome, and great progress in understanding the details of this class of phase transitions has been made, largely based on advances in the growth of high-quality, epitaxial ferroelectric films and in the theory and simulation of ferroelectricity. Here we will discuss recent progress in understanding the ferroelectric phase transition in a particular class of model systems: nanoscale perovskite thin-film heterostructures. The outlook for ferroelectric technology based on these results is promising, and extensions to laterally confined nanostructures will be described.

Streiffer, S. K.; Fong, D. D. (Center for Nanoscale Materials); ( MSD)

2009-01-01T23:59:59.000Z

331

The Water Vapor Abundance in Orion KL Outflows  

E-Print Network (OSTI)

We present the detection and modeling of more than 70 far-IR pure rotational lines of water vapor, including the 18O and 17O isotopologues, towards Orion KL. Observations were performed with the Long Wavelength Spectrometer Fabry-Perot (LWS/FP; R~6800-9700) on board the Infrared Space Observatory (ISO) between ~43 and ~197 um. The water line profiles evolve from P-Cygni type profiles (even for the H2O18 lines) to pure emission at wavelengths above ~100 um. We find that most of the water emission/absorption arises from an extended flow of gas expanding at 25+-5 kms^-1. Non-local radiative transfer models show that much of the water excitation and line profile formation is driven by the dust continuum emission. The derived beam averaged water abundance is 2-3x10^-5. The inferred gas temperature Tk=80-100 K suggests that: (i) water could have been formed in the "plateau" by gas phase neutral-neutral reactions with activation barriers if the gas was previously heated (e.g. by shocks) to >500 K and/or (ii) H2O formation in the outflow is dominated by in-situ evaporation of grain water-ice mantles and/or (iii) H2O was formed in the innermost and warmer regions (e.g. the hot core) and was swept up in ~1000 yr, the dynamical timescale of the outflow.

J. Cernicharo; J. R. Goicoechea; F. Daniel; M. R. Lerate; M. J. Barlow; B. M. Swinyard; E. van Dishoeck; T. L. Lim; S. Viti; J. Yates

2006-08-16T23:59:59.000Z

332

FFT-LB modeling of thermal liquid-vapor systems  

E-Print Network (OSTI)

We further develop a thermal LB model for multiphase flows. In the improved model, we propose to use the FFT scheme to calculate both the convection term and external force term. The usage of FFT scheme is detailed and analyzed. By using the FFT algorithm spatiotemporal discretization errors are decreased dramatically and the conservation of total energy is much better preserved. A direct consequence of the improvement is that the unphysical spurious velocities at the interfacial regions can be damped to neglectable scale. Together with the better conservation of total energy, the more accurate flow velocities lead to the more accurate temperature field which determines the dynamical and final states of the system. With the new model, the phase diagram of the liquid-vapor system obtained from simulation is more consistent with that from theoretical calculation. Very sharp interfaces can be achieved. The accuracy of simulation results are also verified by the Laplace law. The FFT scheme can be easily applied to other models for multiphase flows.

Yanbiao Gan; Aiguo Xu; Guangcai Zhang; Yingjun Li

2010-11-16T23:59:59.000Z

333

Chemical vapor deposition of amorphous silicon films from disilane  

SciTech Connect

Amorphous silicon films for fabrication of solar cells have been deposited by thermal chemical vapor deposition (CVD) from disilane (Si/sub 2/H/sub 6/) using a tubular flow reactor. A mathematical description for the CVD reactor was developed and solved by a numerical procedure. The proposed chemical reaction network for the model is based on silylene (SiH/sub 2/) insertion in the gas phase and film growth from SiH/sub 2/ and silicon polymers (Si/sub n/N/sub 2n/, n approx. 10). Estimates of the rate constants have been obtained for trisilane decomposition, silicon polymer formation, and polymer dehydrogenation. The silane unimolecular decomposition rate constants were corrected for pressure effects. The model behavior is compared to the experimental results over the range of conditions: reactor temperature (360 to 485/sup 0/C), pressures (2 to 48 torr), and gas holding time (1 to 70 s). Within the above range of conditions, film growth rate varies from 0.01 to 30 A/s. Results indicate that silicon polymers are the main film precursors for gas holding times greater than 3 s. Film growth by silylene only becomes important at short holding times, large inert gas dilution, and positions near the beginning of the reactor hot zone.

Bogaert, R.J.

1986-01-01T23:59:59.000Z

334

Wavelength controlled InAs/InP quantum dots for telecom laser applications  

Science Conference Proceedings (OSTI)

This article reviews the recent progress in the growth and device applications of InAs/InP quantum dots (QDs) for telecom applications. Wavelength tuning of the metalorganic vapor-phase epitaxy grown single layer and stacked InAs QDs embedded in InGaAsP/InP ... Keywords: InAs, InGaAsP, InP (100), Laser, Metalorganic vapor-phase epitaxy, Quantum dot

S. Anantathanasarn; R. Nötzel; P. J. van Veldhoven; F. W. M. van Otten; Y. Barbarin; G. Servanton; T. de Vries; E. Smalbrugge; E. J. Geluk; T. J. Eijkemans; E. A. J. M. Bente; Y. S. Oei; M. K. Smit; J. H. Wolter

2006-12-01T23:59:59.000Z

335

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR  

E-Print Network (OSTI)

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR By SCOTT RUSSELL WAITUKAITIS A Thesis Submitted: #12;Abstract I describe a study of Faraday rotation in a hot lithium vapor. I begin by dis- cussing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 The Lithium Oven and Solenoid . . . . . . . . . . . . . . . . . 7 3 Theoretical Framework

Cronin, Alex D.

336

New Regenerative Cycle for Vapor Compression Refrigeration  

Office of Scientific and Technical Information (OSTI)

SCIENTIFIC REPORT SCIENTIFIC REPORT Title Page Project Title: New Regenerative Cycle for Vapor Compression Refrigeration DOE Award Number: DE-FG36-04GO14327 Document Title: Final Scientific Report Period Covered by Report: September 30, 2004 to September 30, 2005 Name and Address of Recipient Organization: Magnetic Development, Inc., 68 Winterhill Road, Madison, CT 06443, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Contact Information: Mark J. Bergander, Ph.D., P.E., Principal Investigator, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Project Objective (as stated in the proposal): The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient

337

FLAMMABILITY CHARACTERISTICS OF COMBUSTIBLE GASES AND VAPORS  

Office of Scientific and Technical Information (OSTI)

Bulletin 627 Bulletin 627 BUREAU o b MINES FLAMMABILITY CHARACTERISTICS OF COMBUSTIBLE GASES AND VAPORS By Michael G. Zabetakis DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement,

338

Gas transport model for chemical vapor infiltration  

Science Conference Proceedings (OSTI)

A node-bond percolation model is presented for the gas permeability and pore surface area of the coarse porosity in woven fiber structures during densification by chemical vapor infiltration (CVI). Model parameters include the number of nodes per unit volume and their spatial distribution, and the node and bond radii and their variability. These parameters relate directly to structural features of the weave. Some uncertainty exists in the proper partition of the porosity between ``node`` and ``bond`` and between intra-tow and inter-tow, although the total is constrained by the known fiber loading in the structure. Applied to cloth layup preforms the model gives good agreement with the limited number of available measurements.

Starr, T.L. [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States)

1995-09-01T23:59:59.000Z

339

Hybrid Vapor Compression Adsorption System: Thermal Storage Using Hybrid Vapor Compression Adsorption System  

SciTech Connect

HEATS Project: UTRC is developing a new climate-control system for EVs that uses a hybrid vapor compression adsorption system with thermal energy storage. The targeted, closed system will use energy during the battery-charging step to recharge the thermal storage, and it will use minimal power to provide cooling or heating to the cabin during a drive cycle. The team will use a unique approach of absorbing a refrigerant on a metal salt, which will create a lightweight, high-energy-density refrigerant. This unique working pair can operate indefinitely as a traditional vapor compression heat pump using electrical energy, if desired. The project will deliver a hot-and-cold battery that provides comfort to the passengers using minimal power, substantially extending the driving range of EVs.

None

2012-01-04T23:59:59.000Z

340

Structure of epitaxial (Fe,N) codoped rutile TiO2 thin films by x-ray absorption  

Science Conference Proceedings (OSTI)

Homoepitaxial thin films of Fe:TiO2 and (Fe,N):TiO2 were deposited on rutile(110) by molecular beam epitaxy. X-ray absorption near edge spectroscopy (XANES) spectra were collected at the Ti L-edge, Fe L-edge, O K-edge, N K-edge, and Ti K-edge. No evidence of structural disorder associated with a high concentration of oxygen vacancies is observed. Substitution of Fe for Ti could not be confirmed, although secondary phase Fe2O3 and metallic Fe can be ruled out. The similarity of the N K-edge spectra to O, and the presence of a strong x-ray linear dichroism (XLD) signal for the N K-edge, indicates that N is substitutional for O in the rutile lattice, and is not present as a secondary phase such as TiN. Simulations of the XANES spectra qualitatively confirm substitution, although N appears to be present in more than one local environment. Neither Fe:TiO2 nor (Fe,N):TiO2 exhibit intrinsic room temperature ferromagnetism, despite the presence of mixed valence Fe(II)/Fe(III) in the reduced (Fe,N):TiO2 film.

Kaspar, Tiffany C.; Ney, A.; Mangham, Andrew N.; Heald, Steve M.; Joly, Yves; Ney, V.; Wilhelm, F.; Rogalev, A.; Yakou, Flora; Chambers, Scott A.

2012-07-23T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Worker Protection from Chemical Vapors: Hanford Tank Farms  

Science Conference Proceedings (OSTI)

Chemical vapor emissions from underground hazardous waste storage tanks on the Hanford site in eastern Washington State are a potential concern because workers enter the tank farms on a regular basis for waste retrievals, equipment maintenance, and surveillance. Tank farm contractors are in the process of retrieving all remaining waste from aging single-shell tanks, some of which date to World War II, and transferring it to newer double-shell tanks. During the waste retrieval process, tank farm workers are potentially exposed to fugitive chemical vapors that can escape from tank head-spaces and other emission points. The tanks are known to hold more than 1,500 different species of chemicals, in addition to radionuclides. Exposure assessments have fully characterized the hazards from chemical vapors in half of the tank farms. Extensive sampling and analysis has been done to characterize the chemical properties of hazardous waste and to evaluate potential health hazards of vapors at the ground surface, where workers perform maintenance and waste transfer activities. Worker concerns, risk communication, and exposure assessment are discussed, including evaluation of the potential hazards of complex mixtures of chemical vapors. Concentrations of vapors above occupational exposure limits (OEL) were detected only at exhaust stacks and passive breather filter outlets. Beyond five feet from the sources, vapors disperse rapidly. No vapors have been measured above 50% of their OELs more than five feet from the source. Vapor controls are focused on limited hazard zones around sources. Further evaluations of vapors include analysis of routes of exposure and thorough analysis of nuisance odors. (authors)

Anderson, T.J. [CH2M HILL Hanford Group, Inc. / Environmental Health, Richland, WA (United States)

2007-07-01T23:59:59.000Z

342

Thermodynamics Resource: Gas-Phase Database and the Condensed-Phase Data File  

DOE Data Explorer (OSTI)

The Thermodynamics Resource provides thermochemistry for gas-phase and condensed species relevant to a wide range of high-temperature processes, including chemical vapor deposition (CVD), chemical vapor infiltration (CVI), catalysis, combustion, materials corrosion, and aerosol processing. Thermochemistry is the foundation for understanding chemical reactions and as such is essential to the development of predictive models for many high-temperature processes. The database includes thermodynamic data (heats of formation, enthalpies, entropies, and heat capacities) for gas and condensed-phase species, thermodynamic models for specific condensed-phase material systems that account for non-ideal behavior in those systems, and a wide range of calculated molecular properties for gas-phase species. (Specialized Interface)

Allendorf, Mark D.; Besmann, Theodore M.

343

The control of size and areal density of InAs self-assembled quantum dots in selective area molecular beam epitaxy on GaAs (001) surface  

Science Conference Proceedings (OSTI)

The growth of InAs quantum dots (QDs) on GaAs (001) substrates by selective area molecular beam epitaxy (SA-MBE) with dielectric mask is investigated. The GaAs polycrystals on the mask, which is formed during growth due to low GaAs selectivity between ... Keywords: InAs quantum dots, Molecular beam epitaxy, Selective area epitaxy

J. C. Lin; P. W. Fry; R. A. Hogg; M. Hopkinson; I. M. Ross; A. G. Cullis; R. S. Kolodka; A. I. Tartakovskii; M. S. Skolnick

2006-12-01T23:59:59.000Z

344

The Effects of Water Vapor on the Oxidation of Nickel-Base ...  

Science Conference Proceedings (OSTI)

water vapor are compared at temperatures from 700°C to 1100°C. It is shown that water vapor affects the oxidation of such alloys in different ways. Water vapor ...

345

Water Vapor Flux Measurements from Ground-Based Vertically Pointed Water Vapor Differential Absorption and Doppler Lidars  

Science Conference Proceedings (OSTI)

For the first time, two lidar systems were used to measure the vertical water vapor flux in a convective boundary layer by means of eddy correlation. This was achieved by combining a water vapor differential absorption lidar and a heterodyne wind ...

Andreas Giez; Gerhard Ehret; Ronald L. Schwiesow; Kenneth J. Davis; Donald H. Lenschow

1999-02-01T23:59:59.000Z

346

Structural controlled magnetic anisotropy in Heusler L1{sub 0}-MnGa epitaxial thin films  

Science Conference Proceedings (OSTI)

Ferromagnetic L1{sub 0}-MnGa thin films have been epitaxially grown on GaN, sapphire, and MgO substrates using molecular beam epitaxy. Using diffraction techniques, the epitaxial relationships are determined. It is found that the crystalline orientation of the films differ due to the influence of the substrate. By comparing the magnetic anisotropy to the structural properties, a clear correlation could be established indicating that the in-plane and out-of-plane anisotropy is directly determined by the crystal orientation of the film and could be controlled via selection of the substrates. This result could be helpful in tailoring magnetic anisotropy in thin films for spintronic applications.

Wang Kangkang; Lu Erdong; Smith, Arthur R. [Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, Ohio 45701 (United States); Knepper, Jacob W.; Yang Fengyuan [Department of Physics, Ohio State University, 191 Woodruff Ave., Columbus, Ohio 43210 (United States)

2011-04-18T23:59:59.000Z

347

An ultra-thin buffer layer for Ge epitaxial layers on Si  

SciTech Connect

Using an Fe{sub 3}Si insertion layer, we study epitaxial growth of Ge layers on a Si substrate by a low-temperature molecular beam epitaxy technique. When we insert only a 10-nm-thick Fe{sub 3}Si layer in between Si and Ge, epitaxial Ge layers can be obtained on Si. The detailed structural characterizations reveal that a large lattice mismatch of {approx}4% is completely relaxed in the Fe{sub 3}Si layer. This means that the Fe{sub 3}Si layers can become ultra-thin buffer layers for Ge on Si. This method will give a way to realize a universal buffer layer for Ge, GaAs, and related devices on a Si platform.

Kawano, M.; Yamada, S.; Tanikawa, K.; Miyao, M.; Hamaya, K. [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan)] [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Sawano, K. [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan)] [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan)

2013-03-25T23:59:59.000Z

348

Phase five  

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

Phase five Phase five 1663 Los Alamos science and technology magazine Latest Issue:November 2013 All Issues » submit Phase five Los Alamos physicists have conclusively demonstrated the existence of a new phase of matter. November 25, 2013 Phase five Scientists still have more to learn about the exotic physics of specialty materials. What makes the cuprates special? How about a new phase of matter. Ceramic metals known as cuprates have mystified physicists for decades. They exhibit a variety of distinct phases of matter, each with its own specific properties, including a phase bearing an exotic type of magnetism, a high-temperature superconducting phase, an ordinary metal phase, a poorly understood and weird metallic phase simply called a strange metal, and an equally poorly understood metallic phase known as the pseudogap. The

349

Ion-assisted doping of 2-6 compounds during physical vapor deposition  

DOE Green Energy (OSTI)

This report describes a research program to (1) investigate ion-assisted doping during chemical vapor deposition of CdTe and (2) determine the influence of co-depositing ionized dopant atoms in the growth and structural and photoelectronic properties of the deposited films. In p-CdTe homo-epitaxial films, we controlled doping up to about 6 {times} 10{sup 16} cm{sup {minus}3} and 2 {times} 10{sup 17} cm{sub {minus}3} or ion-assisted depositions with As and P ions, respectively. At a growth rate of approximately 0.1 {mu}m/min, a substrate temperature of 400{degree}C, and ion energy of 60 eV, a maximum doping density was found near an ion current of 0.6{mu}A/cm{sup 2}. Related studies included elucidating the role of low-energy ion damage in the ion-assisted doping process, and investigating the decrease in carrier density near the surface of p-CdTe upon heating in vacuum, H{sub 2}, or Ar. We demonstrate the ability to make carrier density profiles and to grade junctions, and we present preliminary results from polycrystalline p-CdTe films grown on graphite and alumina substrates. We also present solar cells prepared using the p-CdTe as the collector area and n-CdS as the window layer, and we examine their photovoltaic parameters for different carrier densities and configurations in p-CdTe. 91 refs., 44 figs., 5 tabs.

Bube, R H [Stanford Univ., CA (USA). Dept. of Materials Science and Engineering

1990-07-01T23:59:59.000Z

350

Phase equilibrium studies  

DOE Green Energy (OSTI)

A phase equilibrium model has been developed for the SRC-I process, as well as the other coal liquefaction processes. It is applicable to both vapor/liquid and liquid/liquid equilibria; it also provides an approximate but adequate description of aqueous mixtures where the volatile electrolyte components dissociate to form ionic species. This report completes the description of the model presented in an earlier report (Mathias and Stein, 1983a). Comparisons of the model to previously published data on coal-fluid mixtures are presented. Further, a preliminary analysis of new data on SRC-I coal fluids is presented. Finally, the current capabilities and deficiencies of the model are discussed. 25 references, 17 figures, 30 tables.

Mathias, P.M.; Stein, F.P.

1983-09-01T23:59:59.000Z

351

Epitaxial growth on silicon and characterization of MnF{sub 2} and ZnF{sub 2} layers with metastable orthorhombic structure  

SciTech Connect

The growth of MnF{sub 2} and ZnF{sub 2} layers on Si(001) and Si(111) substrates was studied by molecular-beam epitaxy. Calcium fluoride buffer layers with (001) (110), and (111) orientations were used to prevent chemical interaction of MnF{sub 2} and ZnF{sub 2} molecules with the Si substrate. The analysis of x-ray and reflection high-energy electron-diffraction (RHEED) patterns showed that MnF{sub 2} layers grow on all of these planes in the orthorhombic {alpha}-PbO{sub 2}-type crystal phase observed earlier only at high pressures and temperatures. Atomic force microscopy revealed a strong dependence of the surface morphology on the buffer orientation and growth temperature. The best-ordered MnF{sub 2} growth occurred at 500 deg. C on a CaF{sub 2} (110) buffer layer. The diffraction analysis enabled us to find the epitaxial relations at the MnF{sub 2}/CaF{sub 2} interface. A careful analysis of the RHEED patterns of the films grown on CaF{sub 2}(001) showed a similarity in the structure and growth modes between MnF{sub 2} and ZnF{sub 2} layers, with ZnF{sub 2} tending to form multiphase layers. These findings are in agreement with the x-ray diffraction measurements.

Kaveev, A.K.; Anisimov, O.V.; Banshchikov, A.G.; Kartenko, N.F.; Ulin, V.P.; Sokolov, N.S. [Ioffe Physico-Technical Institute Russian Academy of Sciences, St. Petersburg 194021 (Russian Federation)

2005-07-01T23:59:59.000Z

352

Infrared phonon structure in epitaxial films of Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub 10} at low temperatures  

SciTech Connect

We have used both bolometric and cavity techniques to obtain accurate submillimeter and microwave loss data for epitaxial thin films of Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub 10} at low temperatures. These films have {Tc}=121.5 K, are c-axis oriented, contain some volume fraction of the 2:1:2:2 phase, and are characterized by excellent in-plane epitaxy. The absorptivity of these films at 100 cm{sup {minus}1} is a factor of five lower than that obtained by others from a reflectivity measurement on a ceramic sample. We observe strong phonon structure for frequencies between 70 and 600 cm{sup {minus}1}, which are in agreement with a lattice dynamical calculation. Our results show remarkably similar phonon structure to that observed in the ceramic sample. This is in strong contrast to the case for other high {Tc} superconductors such as YBa{sub 2}Cu{sub 3}O{sub 7}, where phonon structure observed in ceramic samples in absent in epitaxial oriented films and crystals because of the electronic screening due to the high conductivity of the a-b planes. At microwave frequencies the absorptivity follows a frequency squared dependence, and is consistent with the submillimeter results. 6 refs.

Miller, D.; Richards, P.L. [Lawrence Berkeley Lab., CA (United States); Lee, W.Y. [IBM Research Div., San Jose, CA (United States). Almaden Research Center; Newman, N.; Garrison, S.M. [Conductus, Inc., Sunnyvale, CA (United States); Martens, J.S. [Sandia National Labs., Albuquerque, NM (United States)

1992-02-01T23:59:59.000Z

353

Site-controlled Ag nanocrystals grown by molecular beam epitaxy-Towards plasmonic integration technology  

Science Conference Proceedings (OSTI)

We demonstrate site-controlled growth of epitaxial Ag nanocrystals on patterned GaAs substrates by molecular beam epitaxy with high degree of long-range uniformity. The alignment is based on lithographically defined holes in which position controlled InAs quantum dots are grown. The Ag nanocrystals self-align preferentially on top of the InAs quantum dots. No such ordering is observed in the absence of InAs quantum dots, proving that the ordering is strain-driven. The presented technique facilitates the placement of active plasmonic nanostructures at arbitrarily defined positions enabling their integration into complex devices and plasmonic circuits.

Urbanczyk, Adam [COBRA Research Institute on Communication Technology, Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Noetzel, Richard [Institute for Systems based on Optoelectronics and Microtechnology (ISOM), ETSI Telecommunication, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain)

2012-12-15T23:59:59.000Z

354

Magnetism and transport properties of epitaxial Fe-Ga thin films on GaAs(001)  

SciTech Connect

Epitaxial Fe-Ga thin films in disordered bcc {alpha}-Fe crystal structure (A2) have been grown on GaAs(001) by molecular beam epitaxy. The saturated magnetization (M{sub S}) decreased from 1371 to 1105 kA/m with increasing Ga concentration from 10.5 to 24.3 % at room temperature. The lattice parameter increased with the increase in Ga content because of the larger atomic radius of Ga atom than that of Fe. The increase in carrier density with Ga content caused in lower resistivity.

Duong Anh Tuan; Shin, Yooleemi; Cho, Sunglae [Department of Physics, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Dang Duc Dung [Department of Physics, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Department of General Physics, School of Engineering Physics, Ha Noi University of Science and Technology, 1 Dai Co Viet road, Ha Noi (Viet Nam); Vo Thanh Son [Centers for Nanobioenineering and Spintronics, Chungnam National University, Daejon 350-746 (Korea, Republic of)

2012-04-01T23:59:59.000Z

355

Understanding controls on interfacial wetting at epitaxial graphene: Experiment and Theory  

SciTech Connect

The interaction of water with graphitic carbon at the atomic scale is studied as a function of the hydrophobicity of epitaxial graphene. High resolution X-ray reflectivity combined with both classical and ab initio molecular dynamics simulations allows us to understand how the graphene-water interface changes as the hydrophobicity of intrinsic multilayer graphene (contact angle c = 93 ) is reduced by the presence of substrate and surface defect sites, leading to increased hydrophilicity ( c = 73 ) for zero-layer graphene (i.e., the epitaxial buffer layer). The relationship between water depletion and hydrophobicity (i.e., the hydrophobic gap) is also clarified by the current findings.

Zhou, Hua [Argonne National Laboratory (ANL); Ganesh, Panchapakesan [ORNL; Presser, Volker [Drexel University; Wander, Matthew C [ORNL; Fenter, Paul [Argonne National Laboratory (ANL); Kent, Paul R [ORNL; Jiang, Deen [ORNL; Chialvo, Ariel A [ORNL; Mcdonough, John [Drexel University; Shuford, Kevin L [ORNL; Gogotsi, Yury G. [Drexel University

2012-01-01T23:59:59.000Z

356

Thermal Design of an Ultrahigh Temperature Vapor Core Reactor Combined Cycle Nuclear Power Plant  

SciTech Connect

Current work modeling high temperature compact heat exchangers may demonstrate the design feasibility of a Vapor Core Reactor (VCR) driven combined cycle power plant. For solid nuclear fuel designs, the cycle efficiency is typically limited by a metallurgical temperature limit which is dictated by fuel and structural melting points. In a vapor core, the gas/vapor phase nuclear fuel is uniformly mixed with the topping cycle working fluid. Heat is generated homogeneously throughout the working fluid thus extending the metallurgical temperature limit. Because of the high temperature, magnetohydrodynamic (MHD) generation is employed for topping cycle power extraction. MHD rejected heat is transported via compact heat exchanger to a conventional Brayton gas turbine bottoming cycle. High bottoming cycle mass flow rates are required to remove the waste heat because of low heat capacities for the bottoming cycle gas. High mass flow is also necessary to balance the high Uranium Tetrafluoride (UF{sub 4}) mass flow rate in the topping cycle. Heat exchanger design is critical due to the high temperatures and corrosive influence of fluoride compounds and fission products existing in VCR/MHD exhaust. Working fluid compositions for the topping cycle include variations of Uranium Tetrafluoride, Helium and various electrical conductivity seeds for the MHD. Bottoming cycle working fluid compositions include variations of Helium and Xenon. Some thought has been given to include liquid metal vapor in the bottoming cycle for a Cheng or evaporative cooled design enhancement. The NASA Glenn Lewis Research Center code Chemical Equilibrium with Applications (CEA) is utilized for evaluating chemical species existing in the gas stream. Work being conducted demonstrates the compact heat exchanger design, utilization of the CEA code, and assessment of different topping and bottoming working fluid compositions. (authors)

Bays, Samuel E.; Anghaie, Samim; Smith, Blair; Knight, Travis [Innovative Space Power and Propulsion Institute, University of Florida, 202 Nuclear Science Building, Gainesville, FL 32611 (United States)

2004-07-01T23:59:59.000Z

357

Mercury Vapor At Silver Peak Area (Henkle, Et Al., 2005) | Open...  

Open Energy Info (EERE)

Mercury Vapor At Silver Peak Area (Henkle, Et Al., 2005) Exploration Activity Details Location Silver Peak Area Exploration Technique Mercury Vapor Activity Date Usefulness useful...

358

EA-0881: Tank 241-c-103 Organic Vapor and Liquid Characterization...  

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

881: Tank 241-c-103 Organic Vapor and Liquid Characterization and Supporting Activities, Hanford Site, Richland, Washington EA-0881: Tank 241-c-103 Organic Vapor and Liquid...

359

Does EIA report water vapor emissions data? - FAQ - U.S. Energy ...  

U.S. Energy Information Administration (EIA)

Does EIA report water vapor emissions data? No. Water vapor is the most abundant greenhouse gas, but most scientists believe that human activity has a very small ...

360

Enhanced Attenuation Technologies: Passive Soil Vapor Extraction  

SciTech Connect

Passive soil vapor extraction (PSVE) is an enhanced attenuation (EA) approach that removes volatile contaminants from soil. The extraction is driven by natural pressure gradients between the subsurface and atmosphere (Barometric Pumping), or by renewable sources of energy such as wind or solar power (Assisted PSVE). The technology is applicable for remediating sites with low levels of contamination and for transitioning sites from active source technologies such as active soil vapor extraction (ASVE) to natural attenuation. PSVE systems are simple to design and operate and are more cost effective than active systems in many scenarios. Thus, PSVE is often appropriate as an interim-remedial or polishing strategy. Over the past decade, PSVE has been demonstrated in the U.S. and in Europe. These demonstrations provide practical information to assist in selecting, designing and implementing the technology. These demonstrations indicate that the technology can be effective in achieving remedial objectives in a timely fashion. The keys to success include: (1) Application at sites where the residual source quantities, and associated fluxes to groundwater, are relatively low; (2) Selection of the appropriate passive energy source - barometric pumping in cases with a deep vadose zone and barrier (e.g., clay) layers that separate the subsurface from the atmosphere and renewable energy assisted PSVE in other settings and where higher flow rates are required. (3) Provision of sufficient access to the contaminated vadose zones through the spacing and number of extraction wells. This PSVE technology report provides a summary of the relevant technical background, real-world case study performance, key design and cost considerations, and a scenario-based cost evaluation. The key design and cost considerations are organized into a flowchart that dovetails with the Enhanced Attenuation: Chlorinated Organics Guidance of the Interstate Technology and Regulatory Council (ITRC). The PSVE flowchart provides a structured process to determine if the technology is, or is not, reasonable and defensible for a particular site. The central basis for that decision is the expected performance of PSVE under the site specific conditions. Will PSVE have sufficient mass removal rates to reduce the release, or flux, of contamination into the underlying groundwater so that the site can meet it overall remedial objectives? The summary technical information, case study experiences, and structured decision process provided in this 'user guide' should assist environmental decision-makers, regulators, and engineers in selecting and successfully implementing PSVE at appropriate sites.

Vangelas, K.; Looney, B.; Kamath, R.; Adamson, D.; Newell, C.

2010-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Desalination Using Vapor-Compression Distillation  

E-Print Network (OSTI)

The ability to produce potable water economically is the primary purpose of seawater desalination research. Reverse osmosis (RO) and multi-stage flash (MSF) cost more than potable water produced from fresh water resources. As an alternative to RO and MSF, this research investigates a high-efficiency mechanical vapor-compression distillation system that employs an improved water flow arrangement. The incoming salt concentration was 0.15% salt for brackish water and 3.5% salt for seawater, whereas the outgoing salt concentration was 1.5% and 7%, respectively. Distillation was performed at 439 K (331oF) and 722 kPa (105 psia) for both brackish water feed and seawater feed. Water costs of the various conditions were calculated for brackish water and seawater feeds using optimum conditions considered as 25 and 20 stages, respectively. For brackish water at a temperature difference of 0.96 K (1.73oF), the energy requirement is 2.0 kWh/m3 (7.53 kWh/kgal). At this condition, the estimated water cost is $0.39/m3 ($1.48/kgal) achieved with 10,000,000 gal/day distillate, 30-year bond, 5% interest rate, and $0.05/kWh electricity. For seawater at a temperature difference of 0.44 K (0.80oF), the energy requirement is 3.97 kWh/m3 (15.0 kWh/kgal) and the estimated water cost is $0.61/m3 ($2.31/kgal). Greater efficiency of the vapor compression system is achieved by connecting multiple evaporators in series, rather than the traditional parallel arrangement. The efficiency results from the gradual increase of salinity in each stage of the series arrangement in comparison to parallel. Calculations using various temperature differences between boiling brine and condensing steam show the series arrangement has the greatest improvement at lower temperature differences. The following table shows the improvement of a series flow arrangement compared to parallel: ?T (K) Improvement (%)*1.111 2.222 3.333 15.21 10.80 8.37 * Incoming salt concentration: 3.5% Outgoing salt concentration: 7% Temperature: 450 K (350oF) Pressure: 928 kPa (120 psig) Stages: 4

Lubis, Mirna R.

2009-05-01T23:59:59.000Z

362

Physicochemical Perturbations of Phase Equilibriums  

E-Print Network (OSTI)

The alternative approach to the displacement of gas/liquid equilibrium is developed on the basis of the Clapeyron equation. The phase transition in the system with well-established properties is taken as a reference process to search for the parameters of phase transition in the perturbed equilibrium system. The main equation, derived in the framework of both classical thermodynamics and statistical mechanics, establishes a correlation between variations of enthalpies of evaporation, \\Delta (\\Delta H), which is induced by perturbations, and the equilibrium vapor pressures. The dissolution of a solute, changing the surface shape, and the effect of the external field of adsorbents are considered as the perturbing actions on the liquid phase. The model provides the unified method for studying (1) solutions, (2) membrane separations (3) surface phenomena, and (4) effect of the adsorption field; it leads to the useful relations between \\Delta (\\Delta H), on the one hand, and the osmotic pressures, the Donnan poten...

Dobruskin, Vladimir Kh

2010-01-01T23:59:59.000Z

363

Lattice mismatched epitaxy of heterostructures for non-nitride green light emitting devices  

E-Print Network (OSTI)

In this project, we implement modern metal organic chemical vapor deposition (MOCVD) technology to fabricate monolithic platforms which integrate traditionally incompatible materials with the ultimate goal of achieving ...

Mori, Michael James

2008-01-01T23:59:59.000Z

364

Numerical simulation of water injection into vapor-dominated reservoirs  

DOE Green Energy (OSTI)

Water injection into vapor-dominated reservoirs is a means of condensate disposal, as well as a reservoir management tool for enhancing energy recovery and reservoir life. We review different approaches to modeling the complex fluid and heat flow processes during injection into vapor-dominated systems. Vapor pressure lowering, grid orientation effects, and physical dispersion of injection plumes from reservoir heterogeneity are important considerations for a realistic modeling of injection effects. An example of detailed three-dimensional modeling of injection experiments at The Geysers is given.

Pruess, K.

1995-01-01T23:59:59.000Z

365

Controlling the vapor pressure of a mercury lamp  

DOE Patents (OSTI)

The invention described herein discloses a method and apparatus for controlling the Hg vapor pressure within a lamp. This is done by establishing and controlling two temperature zones within the lamp. One zone is colder than the other zone. The first zone is called the cold spot. By controlling the temperature of the cold spot, the Hg vapor pressure within the lamp is controlled. Likewise, by controlling the Hg vapor pressure of the lamp, the intensity and linewidth of the radiation emitted from the lamp is controlled.

Grossman, Mark W. (Belmont, MA); George, William A. (Rockport, MA)

1988-01-01T23:59:59.000Z

366

Controlling the vapor pressure of a mercury lamp  

DOE Patents (OSTI)

The invention described herein discloses a method and apparatus for controlling the Hg vapor pressure within a lamp. This is done by establishing and controlling two temperature zones within the lamp. One zone is colder than the other zone. The first zone is called the cold spot. By controlling the temperature of the cold spot, the Hg vapor pressure within the lamp is controlled. Likewise, by controlling the Hg vapor pressure of the lamp, the intensity and linewidth of the radiation emitted from the lamp is controlled. 2 figs.

Grossman, M.W.; George, W.A.

1988-05-24T23:59:59.000Z

367

Simple microwave field imaging technique using hot atomic vapor cells  

E-Print Network (OSTI)

We demonstrate a simple technique for microwave field imaging using alkali atoms in a vapor cell. The microwave field to be measured drives Rabi oscillations on atomic hyperfine transitions, which are detected in a spatially resolved way using a laser beam and a CCD camera. Our vapor cell geometry enables single-shot recording of two-dimensional microwave field images with 350 {\\mu}m spatial resolution. Using microfabricated vapor cell arrays, a resolution of a few micrometers seems feasible. All vector components of the microwave magnetic field can be imaged. Our apparatus is simple and compact and does not require cryogenics or ultra-high vacuum.

Böhi, Pascal

2012-01-01T23:59:59.000Z

368

Simple microwave field imaging technique using hot atomic vapor cells  

E-Print Network (OSTI)

We demonstrate a simple technique for microwave field imaging using alkali atoms in a vapor cell. The microwave field to be measured drives Rabi oscillations on atomic hyperfine transitions, which are detected in a spatially resolved way using a laser beam and a camera. Our vapor cell geometry enables single-shot recording of two-dimensional microwave field images with 350 {\\mu}m spatial resolution. Using microfabricated vapor cell arrays, a resolution of a few micrometers seems feasible. All vector components of the microwave magnetic field can be imaged. Our apparatus is simple and compact and does not require cryogenics or ultra-high vacuum.

Pascal Böhi; Philipp Treutlein

2012-07-20T23:59:59.000Z

369

Mercury Vapor At Medicine Lake Area (Kooten, 1987) | Open Energy  

Open Energy Info (EERE)

Kooten, 1987) Kooten, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Medicine Lake Area (Kooten, 1987) Exploration Activity Details Location Medicine Lake Area Exploration Technique Mercury Vapor Activity Date Usefulness could be useful with more improvements DOE-funding Unknown References Gerald K. Van Kooten (1987) Geothermal Exploration Using Surface Mercury Geochemistry Retrieved from "http://en.openei.org/w/index.php?title=Mercury_Vapor_At_Medicine_Lake_Area_(Kooten,_1987)&oldid=386431" Category: Exploration Activities What links here Related changes Special pages Printable version Permanent link Browse properties 429 Throttled (bot load) Error 429 Throttled (bot load) Throttled (bot load) Guru Meditation:

370

Nanofaceting and alloy decomposition: From basic studies to advanced photonic devices  

Science Conference Proceedings (OSTI)

Most of the modern epitaxial structures for semiconductor lasers serving the needs of optical storage and fiber pumping are grown on misoriented GaAs(001) substrates. It has been found in metal-organic vapor-phase epitaxy that surface misorientation ... Keywords: Alloy decomposition, High resolution, Nanofaceting, Photonic bangap crystal laser, Polarized photoluminescence, Quantum well, Quantum wire, Transmission electron microscopy

V. A. Shchukin; N. N. Ledentsov; I. P. Soshnikov; N. V. Kryzhanovskaya; M. V. Maximov; N. D. Zakharov; P. Werner; D. Bimberg

2006-12-01T23:59:59.000Z

371

Catalytic Reactor For Oxidizing Mercury Vapor  

DOE Patents (OSTI)

A catalytic reactor (10) for oxidizing elemental mercury contained in flue gas is provided. The catalyst reactor (10) comprises within a flue gas conduit a perforated corona discharge plate (30a, b) having a plurality of through openings (33) and a plurality of projecting corona discharge electrodes (31); a perforated electrode plate (40a, b, c) having a plurality of through openings (43) axially aligned with the through openings (33) of the perforated corona discharge plate (30a, b) displaced from and opposing the tips of the corona discharge electrodes (31); and a catalyst member (60a, b, c, d) overlaying that face of the perforated electrode plate (40a, b, c) opposing the tips of the corona discharge electrodes (31). A uniformly distributed corona discharge plasma (1000) is intermittently generated between the plurality of corona discharge electrode tips (31) and the catalyst member (60a, b, c, d) when a stream of flue gas is passed through the conduit. During those periods when corona discharge (1000) is not being generated, the catalyst molecules of the catalyst member (60a, b, c, d) adsorb mercury vapor contained in the passing flue gas. During those periods when corona discharge (1000) is being generated, ions and active radicals contained in the generated corona discharge plasma (1000) desorb the mercury from the catalyst molecules of the catalyst member (60a, b, c, d), oxidizing the mercury in virtually simultaneous manner. The desorption process regenerates and activates the catalyst member molecules.

Helfritch, Dennis J. (Baltimore, MD)

1998-07-28T23:59:59.000Z

372

Dynamics of nucleation in chemical vapor deposition  

Science Conference Proceedings (OSTI)

We study the evolution of layer morphology during the early stages of metal chemical vapor deposition (CVD) onto Si(100) via pyrolysis of Fe(CO){sub 5} below 250{degrees}C. Scanning tunneling microscopy (STM) shows that nuclei formation is limited by precursor dissociation which occurs on terraces, not at step sites. Also, the average size of clusters formed during CVD is larger than for Fe growth by evaporation (a random deposition process). Based on STM data and Monte Carlo simulations, we conclude that the CVD-growth morphology is affected by preferential dissociation of Fe(CO){sub 5} molecules at existing Fe clusters -- an autocatalytic effect. We demonstrate that nucleation kinetics can be used to control formation of metal nanostructures on chemically tailored surfaces. Reactive sites on Si (001) are first passivated by hydrogen. H atoms are locally removed by electron stimulated desorption using electrons emitted from the STM tip. Subsequent pyrolysis of Fe(CO){sub 5} leads to selective nucleation and growth of Fe films in the areas where H has been removed.

Mayer, T.M.; Adams, D.P.; Swartzentruber, B.S.; Chason, E.

1995-11-01T23:59:59.000Z

373

Modeling of LNG Pool Spreading and Vaporization  

E-Print Network (OSTI)

In this work, a source term model for estimating the rate of spreading and vaporization of LNG on land and sea is introduced. The model takes into account the composition changes of the boiling mixture, the varying thermodynamic properties due to preferential boiling within the mixture and the effect of boiling on conductive heat transfer. The heat, mass and momentum balance equations are derived for continuous and instantaneous spills and mixture thermodynamic effects are incorporated. A parameter sensitivity analysis was conducted to determine the effect of boiling heat transfer regimes, friction, thermal contact/roughness correction parameter and VLE/mixture thermodynamics on the pool spreading behavior. The aim was to provide a better understanding of these governing phenomena and their relative importance throughout the pool lifetime. The spread model was validated against available experimental data for pool spreading on concrete and sea. The model is solved using Matlab for two continuous and instantaneous spill scenarios and is validated against experimental data on cryogenic pool spreading found in literature.

Basha, Omar 1988-

2012-12-01T23:59:59.000Z

374

Occupational Exposure Evaluation of Complex Vapor Mixtures at the Hanford Nuclear Waste Site, Washington Work-site Vapor Characterization  

SciTech Connect

Extensive sampling and analysis has been done over the years to characterize the radioactive and chemical properties of hazardous waste stored in 177 underground tanks at the Hanford site in eastern Washington State. The purpose of these analyses was to evaluate safety and environmental concerns related to tank stability. More recently, characterization studies have broadened to evaluate potential health hazards of chemical vapors at the ground surface, where workers perform maintenance and waste transfer activities. Chemical vapor emissions from underground hazardous waste storage tanks on the Hanford site are a potential concern because workers enter the tank farms on a regular basis for waste retrievals, equipment maintenance, and surveillance. The extensive sampling done during this campaign evaluated vapor concentrations of more than 100 different chemical at 70 sites in and around one section of the tank farms. Sampling identified only four vapors (ammonia, nitrous oxide, nitrosodimethylamine, and nitrosomethylethylamine) that were present above occupational exposure limits. These elevated concentrations were detected only at exhaust stacks and passive breather filter outlets. Beyond five feet from the sources, vapors disperse rapidly. No vapors were measured above 10% of their OELs more than five feet from the source. This suggests that vapor controls can be focused on limited hazard zones around sources. (authors)

Anderson, T. J. [CH2M HILL Hanford Group, Inc. / Environmental Health, P.O. Box 1000, S7-70, Richland, WA 99352 (United States)

2006-07-01T23:59:59.000Z

375

MATERIAL QUALITY CHARACTERIZATION OF CDZNTE SUBSTRATES FOR HGCDTE EPITAXY.  

Science Conference Proceedings (OSTI)

CdZnTe (CZT) has been traditionally used as substrate for HgCdTe (MCT) epitaxy. The constraint of good lattice matching plays a fundamental role in the use of this substrate. In, fact, despite the difficulties in growing large area of affordable high-quality substrates, CZT wafers remain the best choice for high yield infrared devices. Nevertheless, material quality of the substrate and epilayer play a limiting role in IR focal plane array (FPA) detector technology. Furthermore, data suggest that the quality of the epilayer is affected by imperfections in the CZT substrate. In addition the pixel size for the current generation of FPAs (less than 20 {micro}m) suggests a need for detailed microscale characterization and an understanding of the substrates and epilayers on at least the spatial scale of the pixel dimensions. In an effort to understand the correlation between material quality and device performances, we have begun to study CZT substrates to investigate bulk and surface properties. The National Synchrotron Light Source (NSLS, BNL) permits a wide variety of material investigations that take advantage of the highly collimated photon radiation emitted from the X-ray and VUV-IR rings. Synchrotron radiation offers the capability to combine good resolution and shorter exposure times than conventional X-ray sources, which allow the ability for high-resolution mapping of relatively large areas in an acceptable amount of time. Transmission X-ray diffraction techniques, such as white beam topography and rocking curves, have already been used for bulk investigation [l] as well as IR transmission microspectroscopy. Surface studies on CZT substrates were performed using X-ray diffraction. By correlating results from the different material and device investigations, we offer a more complete characterization of bulk and surface crystalline quality and their effects on device performance. Information on the location of grain boundaries and precipitates, evaluation of impurity content, and stoichiometry variations will be reported. The ultimate goal is to understand the defects in CZT substrates and their effects on the performance and uniformity of MCT epilayers [2], and then to apply this understanding to produce better infrared detectors.

CARINI, G.A.; BOLOTNIKOV, A.E.; CAMARDA, G.S.; JAMES, R.B.; ET AL.

2005-08-18T23:59:59.000Z

376

Characterization of Epitaxial Film Silicon Solar Cells Grown on Seeded Display Glass: Preprint  

DOE Green Energy (OSTI)

We report characterizations of epitaxial film crystal silicon (c-Si) solar cells with open-circuit voltages (Voc) above 560 mV. The 2-um absorber cells are grown by low-temperature (<750 degrees C) hot-wire CVD (HWCVD) on Corning EAGLE XG display glass coated with a layer-transferred (LT) Si seed. The high Voc is a result of low-defect epitaxial Si (epi-Si) growth and effective hydrogen passivation of defects. The quality of HWCVD epitaxial growth on seeded glass substrates depends on the crystallographic quality of the seed and the morphology of the epitaxial growth surface. Heterojunction devices consist of glass/c-Si LT seed/ epi n+ Si:P/epi n- Si:P/intrinsic a-Si:H/p+ a-Si:H/ITO. Similar devices grown on electronically 'dead' n+ wafers have given Voc {approx}630 mV and {approx}8% efficiency with no light trapping features. Here we study the effects of the seed surface polish on epi-Si quality, how hydrogenation influences the device character, and the dominant junction transport physics.

Young, D. L.; Grover, S.; Teplin, C.; Stradins, P.; LaSalvia, V.; Chuang, T. K.; Couillard, J. G.; Branz, H. M.

2012-06-01T23:59:59.000Z

377

Characterization of Epitaxial Film Silicon Solar Cells Grown on Seeded Display Glass: Preprint  

Science Conference Proceedings (OSTI)

We report characterizations of epitaxial film crystal silicon (c-Si) solar cells with open-circuit voltages (Voc) above 560 mV. The 2-um absorber cells are grown by low-temperature (EAGLE XG display glass coated with a layer-transferred (LT) Si seed. The high Voc is a result of low-defect epitaxial Si (epi-Si) growth and effective hydrogen passivation of defects. The quality of HWCVD epitaxial growth on seeded glass substrates depends on the crystallographic quality of the seed and the morphology of the epitaxial growth surface. Heterojunction devices consist of glass/c-Si LT seed/ epi n+ Si:P/epi n- Si:P/intrinsic a-Si:H/p+ a-Si:H/ITO. Similar devices grown on electronically 'dead' n+ wafers have given Voc {approx}630 mV and {approx}8% efficiency with no light trapping features. Here we study the effects of the seed surface polish on epi-Si quality, how hydrogenation influences the device character, and the dominant junction transport physics.

Young, D. L.; Grover, S.; Teplin, C.; Stradins, P.; LaSalvia, V.; Chuang, T. K.; Couillard, J. G.; Branz, H. M.

2012-06-01T23:59:59.000Z

378

Fabrication of magnetic tunnel junctions with epitaxial and textured ferromagnetic layers  

DOE Patents (OSTI)

This invention relates to magnetic tunnel junctions and methods for making the magnetic tunnel junctions. The magnetic tunnel junctions include a tunnel barrier oxide layer sandwiched between two ferromagnetic layers both of which are epitaxial or textured with respect to the underlying substrate upon which the magnetic tunnel junctions are grown. The magnetic tunnel junctions provide improved magnetic properties, sharper interfaces and few defects.

Chang, Y. Austin (Middleton, WI); Yang, Jianhua Joshua (Madison, WI)

2008-11-11T23:59:59.000Z

379

Molecular beam epitaxy passivation studies of Ge and III-V semiconductors for advanced CMOS  

Science Conference Proceedings (OSTI)

Future CMOS technologies will require the use of substrate material with a very high mobility in order to fulfil the performance requirements. Therefore, combination of Ge p-MOS with n-MOS devices made out of high mobility III/V compounds, such as GaAs, ... Keywords: High mobility semiconductors, Molecular beam epitaxy (MBE), Passivation

C. Merckling; J. Penaud; D. Kohen; F. Bellenger; A. Alian; G. Brammertz; M. El-Kazzi; M. Houssa; J. Dekoster; M. Caymax; M. Meuris; M. M. Heyns

2009-07-01T23:59:59.000Z

380

Industrial Heat Pumps Using Solid/Vapor Working Fluids  

E-Print Network (OSTI)

Industrial heat pumps have the potential to reduce the operating costs of chemical and heat treating processes in the chemical, petroleum, paper, dairy, and many other industries. The cost development of fossil fuel and other prime energy require excellent efficiency/cost ratios and hardware designs adaptable to specific process needs, in order to compete with vapor re-compression recovery systems. The state-of-the-art heat pump equipment employing liquid/vapor working fluids fulfills the requirements only in some applications. The employment of solid/vapor complex compounds leads to more cost effective heat recovery, which is due to simple hardware with no moving parts, extraordinary low maintenance effort, excellent temperature lifts avoiding the need of two-stage systems, and low first cost. This paper describes the advantages and disadvantages of solid/vapor working media.

Rockenfeller, U.

1986-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

Broadband Water Vapor Transmission Functions for Atmospheric IR Flux Computations  

Science Conference Proceedings (OSTI)

Transmission functions associated with water vapor molecular line and e-type absorption in the IR spectral regions are presented in the form of simple analytical functions and small tables, from which atmospheric IR fluxes and cooling rates can ...

Ming-Dah Chou

1984-05-01T23:59:59.000Z

382

Characterization of Advanced Avalanche Photodiodes for Water Vapor Lidar Receivers  

Science Conference Proceedings (OSTI)

Development of advanced differential absorption lidar (DIAL) receivers is very important to increase the accuracy of atmospheric water vapor measurements. A major component of such receivers is the optical detector. In the near-infrared wavelength range ...

Refaat Tamer F.; Halama Gary E.; DeYoung Russell J.

2000-07-01T23:59:59.000Z

383

ARM - Field Campaign - Arctic Winter Water Vapor IOP  

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

govCampaignsArctic Winter Water Vapor IOP govCampaignsArctic Winter Water Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Arctic Winter Water Vapor IOP 2004.03.09 - 2004.04.09 Lead Scientist : Ed Westwater Data Availability http://www.etl.noaa.gov/programs/2004/wviop/data will contain quicklooks of all of the data. For data sets, see below. Summary During the IOP, the Ground-based Scanning Radiometer of NOAA/ETL, and the ARM MicroWave Radiometer and Microwave Profiler, yielded excellent data over a range of conditions. In all, angular-scanned and calibrated radiometric data from 22.345 to 380 GHz were taken. The Precipitable Water Vapor varied about an order of magnitude from 1 to 10 mm, and surface temperatures varied from about -10 to -40 deg. Celcius. Vaisala RS90

384

Overview of the ARM/FIRE Water Vapor Experiment (AFWEX)  

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

Overview of the ARM/FIRE Water Vapor Overview of the ARM/FIRE Water Vapor Experiment (AFWEX) D. C. Tobin, H. E. Revercomb, and D. D. Turner University of Wisconsin-Madison Madison, Wisconsin Introduction An overview of the ARM/FIRE Water Vapor Experiment (AFWEX) is given. This field experiment was conducted during November-December 2000 near the central ground-based Atmospheric Radiation Measurement (ARM) site in north central Oklahoma, and was sponsored jointly by the ARM, the National Aeronautics and Space Administration (NASA) First ISCCP Regional Experiment (FIRE), and the National Polar-orbiting Operational Environmental Satellite System (NPOESS) programs. Its primary goal was to collect accurate measurements of upper-level (~8 to 12 km) water vapor near the ground-based ARM site. These data are being used to determine the accuracy of measurements that are

385

Numerical analysis of vapor flow in a micro heat pipe  

E-Print Network (OSTI)

The vapor flow in a flat plate micro heat pipe with both uniform and linear heat flux boundary conditions has been numerically analyzed. For both types of boundary conditions, the Navier-Stokes equations with steady incompressible two-dimensional flow were solved using the SIMPLE method. The results indicate that the pressure, shear stress, and friction factor under linear heat flux boundary conditions are considerably smoother, and hence, more closely approximate the real situation. As the heat flux increases, the pressure drop increases, but the friction factor demonstrates only a slight change for different heat flux conditions. The size and shape of the micro heat pipe vapor space was shown to have a significant influence on the vapor flow behavior for micro heat pipes. When the vapor space area decreases, the pressure drop, shear stress, and friction factor all significantly increase.

Liu, Xiaoqin

1996-01-01T23:59:59.000Z

386

Intercomparison of Four Commercial Analyzers for Water Vapor Isotope Measurement  

Science Conference Proceedings (OSTI)

The ?18O and ?D of atmospheric water vapor are important tracers in hydrological and ecological studies. Isotope ratio infrared spectroscopy (IRIS) provides an in situ technology for measuring ?18O and ?D in ambient conditions. An intercomparison ...

Xue-Fa Wen; Xuhui Lee; Xiao-Min Sun; Jian-Lin Wang; Ya-Kun Tang; Sheng-Gong Li; Gui-Rui Yu

2012-02-01T23:59:59.000Z

387

Moisture Vertical Structure, Column Water Vapor, and Tropical Deep Convection  

Science Conference Proceedings (OSTI)

The vertical structure of the relationship between water vapor and precipitation is analyzed in 5 yr of radiosonde and precipitation gauge data from the Nauru Atmospheric Radiation Measurement (ARM) site. The first vertical principal component of ...

Christopher E. Holloway; J. David Neelin

2009-06-01T23:59:59.000Z

388

Improved Magnus Form Approximation of Saturation Vapor Pressure  

Science Conference Proceedings (OSTI)

Algorithms, based on Magnus's form equations, are described that minimize the difference between several relationships between temperature and water vapor pressure at saturation that are commonly used in archiving data. The work was initiated in ...

Oleg A. Alduchov; Robert E. Eskridge

1996-04-01T23:59:59.000Z

389

Advanced Chemical Heat Pumps Using Liquid-Vapor Reactions  

E-Print Network (OSTI)

Chemical heat pumps utilizing liquid-vapor reactions can be configured in forms analogous to electric drive vapor-compression heat pumps and heat activated absorption heat pumps. Basic thermodynamic considerations eliminate some heat pumps and place restrictive working fluid requirements on others, but two thermodynamically feasible systems have significant potential advantage over conventional technology. An electric drive reactive heat pump can use smaller heat exchangers and compressor than a vapor-compression machine, and have more flexible operating characteristics. A waste heat driven heat pump (temperature amplifier) using liquid-vapor chemical reactions- can operate with higher coefficient of performance and smaller heat exchangers than an absorption temperature amplifying heat pump. Higher temperatures and larger temperature lifts should also be possible.

Kirol, L.

1987-09-01T23:59:59.000Z

390

Upper-Tropospheric Water Vapor from UARS MLS  

Science Conference Proceedings (OSTI)

Initial results of upper-tropospheric water vapor obtained from the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS) are presented. MLS is less affected by clouds than infrared or visible techniques, and the UARS ...

W. G. Read; J. W. Waters; D. A. Flower; L. Froidevaux; R. F. Jarnot; D. L. Hartmann; R. S. Harwood; R. B. Rood

1995-12-01T23:59:59.000Z

391

Ice Growth from the Vapor at ?5°C  

Science Conference Proceedings (OSTI)

Results are summarized and illustrated from a long series of experiments on ice growth from the vapor, nearly all in a very small range of conditions: ?5°C, slightly below liquid water saturation, with minimal environmental gradients and no ...

Charles A. Knight

2012-06-01T23:59:59.000Z

392

New Equations for Computing Vapor Pressure and Enhancement Factor  

Science Conference Proceedings (OSTI)

Equations are presented which relate saturation vapor pressure to temperature for moist air. The equations are designed to be easily implemented on a calculator or computer and can be used to convert in either direction. They are more accurate ...

Arden L. Buck

1981-12-01T23:59:59.000Z

393

Solar Radiation Absorption due to Water Vapor: Advanced Broadband Parameterizations  

Science Conference Proceedings (OSTI)

Accurate parameterizations for calculating solar radiation absorption in the atmospheric column due to water vapor lines and continuum are proposed for use in broadband shortwave radiative transfer codes. The error in the absorption values is ...

Tatiana A. Tarasova; Boris A. Fomin

2000-11-01T23:59:59.000Z

394

Water vapor and the dynamics of climate changes  

E-Print Network (OSTI)

Water vapor is not only Earth's dominant greenhouse gas. Through the release of latent heat when it condenses, it also plays an active role in dynamic processes that shape the global circulation of the atmosphere and thus ...

Schneider, Tapio

395

Heat transfer during film condensation of a liquid metal vapor  

E-Print Network (OSTI)

The object of this investigation is to resolve the discrepancy between theory and experiment for the case of heat transfer durirnfilm condensation of liquid metal vapors. Experiments by previous investigators have yielded ...

Sukhatme, S. P.

1964-01-01T23:59:59.000Z

396

Photoinitiated chemical vapor depostion [sic] : mechanism and applications  

E-Print Network (OSTI)

Photoinitiated chemical vapor deposition (piCVD) is developed as a simple, solventless, and rapid method for the deposition of swellable hydrogels and functional hydrogel copolymers. Mechanistic experiments show that piCVD ...

Baxamusa, Salmaan Husain

2009-01-01T23:59:59.000Z

397

Chemical vapor deposition of organosilicon and sacrificial polymer thin films  

E-Print Network (OSTI)

Chemical vapor deposition (CVD) produced films for a wide array of applications from a variety of organosilicon and organic precursors. The structure and properties of thin films were controlled by varying processing ...

Casserly, Thomas Bryan

2005-01-01T23:59:59.000Z

398

The Arm Program's Water Vapor Intensive Observation Periods  

Science Conference Proceedings (OSTI)

A series of water vapor intensive observation periods (WVIOPs) were conducted at the Atmospheric Radiation Measurement (ARM) site in Oklahoma between 1996 and 2000. The goals of these WVIOPs are to characterize the accuracy of the operational ...

H. E. Revercomb; D. D. Turner; D. C. Tobin; R. O. Knuteson; W. F. Feltz; J. Barnard; J. Bösenberg; S. Clough; D. Cook; R. Ferrare; J. Goldsmith; S. Gutman; R. Halthore; B. Lesht; J. Liljegren; H. Linné; J. Michalsky; V. Morris; W. Porch; S. Richardson; B. Schmid; M. Splitt; T. Van Hove; E. Westwater; D. Whiteman

2003-02-01T23:59:59.000Z

399

Column Water Vapor Content in Clear and Cloudy Skies  

Science Conference Proceedings (OSTI)

With radiosonde data from 15 Northern Hemisphere stations, surface-to-400-mb column water vapor is computed from daytime soundings for 1988–1990. On the basis of simultaneous surface visual cloud observations, the data are categorized according ...

Dian J. Gaffen; William P. Elliott

1993-12-01T23:59:59.000Z

400

Initiated chemical vapor deposition of functional polyacrylic thin films  

E-Print Network (OSTI)

Initiated chemical vapor deposition (iCVD) was explored as a novel method for synthesis of functional polyacrylic thin films. The process introduces a peroxide initiator, which can be decomposed at low temperatures (<200?C) ...

Mao, Yu, 1975-

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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.


401

Mercury Vapor At Kawaihae Area (Thomas, 1986) | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor At Kawaihae Area (Thomas, 1986) Mercury Vapor At Kawaihae Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Kawaihae Area (Thomas, 1986) Exploration Activity Details Location Kawaihae Area Exploration Technique Mercury Vapor Activity Date Usefulness not useful DOE-funding Unknown Notes The soil geochemistry yielded quite complex patterns of mercury concentrations and radonemanation rates within the survey area (Cox and Cuff, 1981c). Mercury concentrations (Fig. 38) showed a general minimum along the Kawaihae-Waimea roads and a broad trend of increasing mercury concentrations toward both the north and south. There is no correlation apparent between the mercury patterns and either the resistivity sounding data or the surface geology in the area. The radon emanometry data (Fig.

402

Mercury Vapor At Lualualei Valley Area (Thomas, 1986) | Open Energy  

Open Energy Info (EERE)

Mercury Vapor At Lualualei Valley Area (Thomas, 1986) Mercury Vapor At Lualualei Valley Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Lualualei Valley Area (Thomas, 1986) Exploration Activity Details Location Lualualei Valley Area Exploration Technique Mercury Vapor Activity Date Usefulness useful DOE-funding Unknown Notes Soil mercury and radon emanation surveys were performed over much of the accessible surface of Lualualei Valley (Cox and Thomas, 1979). The results of these surveys (Figs 7 and 8) delineated several areas in which soil mercury concentrations or radon emanation rates were substantially above normal background values. Some of these areas were apparently coincident with the mapped fracture systems associated with the caldera boundaries.

403

Raman Lidar Profiling of Tropospheric Water Vapor over Kangerlussuaq, Greenland  

Science Conference Proceedings (OSTI)

A new measurement capability has been implemented in the Arctic Lidar Technology (ARCLITE) system at the Sondrestrom upper-atmosphere research facility near Kangerlussuaq, Greenland (67.0°N, 50.9°W), enabling estimates of atmospheric water vapor ...

Ryan Reynolds Neely III; Jeffrey P. Thayer

2011-09-01T23:59:59.000Z

404

Lidar Monitoring of the Water Vapor Cycle in the Troposphere  

Science Conference Proceedings (OSTI)

The water vapor mixing ratio distribution in the lower and middle troposphere has been continuously monitored, using an active lidar system. The methodology of the differential absorption laser method used for these measurements is summarized and ...

C. Cahen; G. Megie; P. Flamant

1982-10-01T23:59:59.000Z

405

Injection locked oscillator system for pulsed metal vapor lasers  

SciTech Connect

An injection locked oscillator system for pulsed metal vapor lasers is disclosed. The invention includes the combination of a seeding oscillator with an injection locked oscillator (ILO) for improving the quality, particularly the intensity, of an output laser beam pulse. The present invention includes means for matching the first seeder laser pulses from the seeding oscillator to second laser pulses of a metal vapor laser to improve the quality, and particularly the intensity, of the output laser beam pulse.

Warner, Bruce E. (Livermore, CA); Ault, Earl R. (Dublin, CA)

1988-01-01T23:59:59.000Z

406

Determination of the Vapor Pressure of Lanthanum Fluoride  

SciTech Connect

Preliminary experiments have been made to determine the vapor pressure of lanthanum fluoride between 0.001 and 0.1 millimeter of mercury by means of the Knudsen effusion method. A tantalum cell for this purpose is described. Only preliminary results were obtained and they were all in a relatively high pressure region. However, a plot of the vapor pressure against the reciprocal of absolute temperature approximates a straight line such as would be predicted from theoretical considerations.

Stone, B. D.

1954-04-07T23:59:59.000Z

407

Heat Recovery in Distillation by Mechanical Vapor Recompression  

E-Print Network (OSTI)

A significant reduction in distillation tower energy requirements can be achieved by mechanical vapor recompression. Three design approaches for heating a distillation tower reboiler by mechanical vapor recompression are presented. The advantages of using a screw compressor are discussed in detail. An example of a xylene extraction tower is sited, illustrating the economic attractiveness in which a simple payback period of less than two years is achievable.

Becker, F. E.; Zakak, A. I.

1986-06-01T23:59:59.000Z

408

Grid orientation effects in the simulation of cold water injection into depleted vapor zones  

DOE Green Energy (OSTI)

A considerable body of field experience with injection has been accumulated at Larderello, Italy and The Geysers, California; the results have been mixed. There are well documented cases where injection has increased flow rates of nearby wells. Return of injected fluid as steam from production wells has been observed directly through chemical and isotopic changes of produced fluids (Giovannoni et al., 1981; Nuti et al., 1981). In other cases injection has caused thermal interference and has degraded the temperature and pressure of production wells. Water injection into depleted vapor zones gives rise to complex two-phase fluid flow and heat transfer processes with phase change. These are further complicated by the fractured-porous nature of the reservoir rocks. An optimization of injection design and operating practice is desirable; this requires realistic and robust mathematical modeling capabilities.

Pruess, K.

1991-01-01T23:59:59.000Z

409

Generalization of vapor pressure lowering effects in an existing geothermal simulator  

DOE Green Energy (OSTI)

Thermodynamic properties of pore water are shown to be different from those of bulk water because of interfacial forces between the aqueous and solid phases. This {open_quotes}vapor-pressure lowering{close_quotes} (VPL) effect is described through Kelvin`s equation, which relates VPL to properties of the liquid phase. An algorithm that accounts for VPL had previously been implented in the geothermal simulator TETRAD. This algorithm applies to a narrow range of reservoir properties, and in some cases leads in inconsistencies. This report presents a generalization of the VPL algorithm which removes many of its limitations. The governing equations for the generalization are presented, assumptions and limitations of the method are discussed, and the modifications are validated.

Shook, G.M.

1993-06-01T23:59:59.000Z

410

Properties of molecular beam epitaxy grown Eu{sub x}(transition metal){sub y} films (transition metals: Mn, Cr)  

Science Conference Proceedings (OSTI)

The electronic and crystallographic structures, as well as the magnetic properties, of Eu{sub x}(transition metal){sub y} (transition metals: Mn, Cr) thin films grown by molecular beam epitaxy were studied. Relative changes of the Eu/Mn and Eu/Cr ratios derived from the XPS lines, as well as x-ray reflectivity, indicate mixing of the Eu/Mn and Eu/Cr layers. Valency transitions from Eu{sup 2+} to Eu{sup 3+} were observed in both systems for most studied stoichiometries. A transition to a magnetically ordered phase was observed at 15 K, 40 K, and 62 K for selected films in the Eu-Mn system, and at 50 K for the film with a Eu/Cr ratio of 0.5.

Balin, K. [A. Chelkowski Institute of Physics, University of Silesia, Katowice, 40-007 (Poland); Center for Magnetism and Magnetic Nanostructures, University of Colorado at Colorado Springs, Colorado Springs, Colorado 80918 (United States); Nowak, A. [A. Chelkowski Institute of Physics, University of Silesia, Katowice, 40-007 (Poland); Laboratoire de Physique de l'Etat Condense, University du Maine, Le Mans Cedex, 72085 (France); Gibaud, A. [Laboratoire de Physique de l'Etat Condense, University du Maine, Le Mans Cedex, 72085 (France); Szade, J. [A. Chelkowski Institute of Physics, University of Silesia, Katowice, 40-007 (Poland); Celinski, Z. [Center for Magnetism and Magnetic Nanostructures, University of Colorado at Colorado Springs, Colorado Springs, Colorado 80918 (United States)

2011-04-01T23:59:59.000Z

411

Magnetic properties of MnSb inclusions formed in GaSb matrix directly during molecular beam epitaxial growth  

Science Conference Proceedings (OSTI)

Despite of intensive search for the proper semiconductor base materials for spintronic devices working at room temperature no appropriate material based on ferromagnetic semiconductors has been found so far. We demonstrate that the phase segregated system with MnSb hexagonal inclusions inside the GaSb matrix, formed directly during the molecular beam epitaxial growth reveals the ferromagnetic properties at room temperature and is a good candidate for exploitation in spintronics. Furthermore, the MnSb inclusions with only one crystalline structure were identified in this GaMn:MnSb granular material. The SQUID magnetometry confirmed that this material exhibits ferromagnetic like behavior starting from helium up to room temperature. Moreover, the magnetic anisotropy was found which was present also at room temperature, and it was proved that by choosing a proper substrate it is possible to control the direction of easy axis of inclusions' magnetization moment between in-plane and out-of-plane; the latter is important in view of potential applications in spintronic devices.

Lawniczak-Jablonska, Krystyna; Wolska, Anna; Klepka, Marcin T.; Kret, Slawomir; Kurowska, Boguslawa; Kowalski, Bogdan J. [Institute of Physics PAS, al. Lotnikow 32/46, 02-668 Warsaw (Poland); Gosk, Jacek [Institute of Experimental Physics, University of Warsaw, Hoza 69, 00-681 Warsaw (Poland); Faculty of Physics, Warsaw University of Technology, Koszykowa 75, 00-662 Warsaw (Poland); Twardowski, Andrzej; Wasik, Dariusz; Kwiatkowski, Adam [Institute of Experimental Physics, University of Warsaw, Hoza 69, 00-681 Warsaw (Poland); Sadowski, Janusz [Institute of Physics PAS, al. Lotnikow 32/46, 02-668 Warsaw (Poland); MAX-Lab, Lund University, SE-221 00 Lund (Sweden)

2011-04-01T23:59:59.000Z

412

ARM: Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals  

DOE Data Explorer (OSTI)

Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

Maria Cadeddu

413

Low temperature plasma enhanced chemical vapor deposition of silicon oxide films using disilane and nitrous oxide  

Science Conference Proceedings (OSTI)

Keywords: disilane, low temperature, nitrous oxide, plasma enhanced chemical vapor deposition, silicon oxide

Juho Song; G. S. Lee; P. K. Ajmera

1995-10-01T23:59:59.000Z

414

Low-temperature formation of epitaxial graphene on 6H-SiC induced by continuous electron beam irradiation  

Science Conference Proceedings (OSTI)

It is observed that epitaxial graphene forms on the surface of a 6H-SiC substrate by irradiating electron beam directly on the sample surface in high vacuum at relatively low temperature ({approx}670 Degree-Sign C). The symmetric shape and full width at half maximum of 2D peak in the Raman spectra indicate that the formed epitaxial graphene is turbostratic. The gradual change of the Raman spectra with electron beam irradiation time increasing suggests that randomly distributed small grains of epitaxial graphene form first and grow laterally to cover the entire irradiated area. The sheet resistance of epitaxial graphene film is measured to be {approx}6.7 k{Omega}/sq.

Go, Heungseok; Jeon, Youngeun; Park, Kibog [School of Electrical and Computer Engineering, KIER-UNIST Advanced Center for Energy, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); Kwak, Jinsung; Yoo, Jung-Woo; Youb Kim, Sung; Kwon, Soon-Yong [School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); Kim, Sung-Dae; Kim, Young-Woon [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Cheol Lee, Byung; Suk Kang, Hyun [Quantum Optics Laboratory, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Ko, Jae-Hyeon [Department of Physics, Hallym University, Chuncheon Gangwondo 200-702 (Korea, Republic of); Kim, Nam [Division of Convergence Technology, Korea Research Institute of Standards and Science, Daejeon 305-340 (Korea, Republic of); Kim, Bum-Kyu [Department of Physics, Chonbuk National University, Jeonju Chonbuk 561-756 (Korea, Republic of)

2012-08-27T23:59:59.000Z

415

Dynamic modeling of plasma-vapor interactions during plasma disruptions  

SciTech Connect

Intense deposition of energy in short times on fusion reactor components during a plasma disruption may cause severe surface erosion due to ablation of these components. The exact amount of the eroded material is very important to the reactor design and its lifetime. During the plasma deposition, the vaporized wall material will interact with the incoming plasma particles and may shield the rest of the wall from damage. The vapor shielding may then prolong the lifetime of these components and increase the reactor duty cycle. To correctly evaluate the impact of vapor shielding effect a comprehensive model is developed. In this model the dynamic slowing down of the plasma particles, both ions and electrons, with the eroded wall material is established. Different interaction processes between the plasma particles and the ablated material is included. The generated photons radiation source and the transport of this radiation through the vapor to the wall is modeled. Recent experimental data on disruptions is analyzed and compared with model predictions. Vapor shielding may be effective in reducing the overall erosion rate for certain plasma disruption parameters and conditions.

Hassanein, A.; Ehst, D.A.

1992-05-01T23:59:59.000Z

416

Vapor etching of nuclear tracks in dielectric materials  

DOE Patents (OSTI)

A process involving vapor etching of nuclear tracks in dielectric materials for creating high aspect ratio (i.e., length much greater than diameter), isolated cylindrical holes in dielectric materials that have been exposed to high-energy atomic particles. The process includes cleaning the surface of the tracked material and exposing the cleaned surface to a vapor of a suitable etchant. Independent control of the temperatures of the vapor and the tracked materials provide the means to vary separately the etch rates for the latent track region and the non-tracked material. As a rule, the tracked regions etch at a greater rate than the non-tracked regions. In addition, the vapor-etched holes can be enlarged and smoothed by subsequent dipping in a liquid etchant. The 20-1000 nm diameter holes resulting from the vapor etching process can be useful as molds for electroplating nanometer-sized filaments, etching gate cavities for deposition of nano-cones, developing high-aspect ratio holes in trackable resists, and as filters for a variety of molecular-sized particles in virtually any liquid or gas by selecting the dielectric material that is compatible with the liquid or gas of interest.

Musket, Ronald G. (Danville, CA); Porter, John D. (Berkeley, CA); Yoshiyama, James M. (Fremont, CA); Contolini, Robert J. (Lake Oswego, OR)

2000-01-01T23:59:59.000Z

417

Drying of pulverized material with heated condensible vapor  

DOE Patents (OSTI)

Apparatus for drying pulverized material utilizes a high enthalpy condensable vapor such as steam for removing moisture from the individual particles of the pulverized material. The initially wet particulate material is tangentially delivered by a carrier vapor flow to an upper portion of a generally vertical cylindrical separation drum. The lateral wall of the separation drum is provided with a plurality of flow guides for directing the vapor tangentially therein in the direction of particulate material flow. Positioned concentrically within the separation drum and along the longitudinal axis thereof is a water-cooled condensation cylinder which is provided with a plurality of collection plates, or fines, on the outer lateral surface thereof. The cooled collection fines are aligned counter to the flow of the pulverized material and high enthalpy vapor mixture to maximize water vapor condensation thereon. The condensed liquid which includes moisture removed from the pulverized materials then flows downward along the outer surface of the coolant cylinder and is collected and removed. The particles travel in a shallow helix due to respective centrifugal and vertical acceleration forces applied thereto. The individual particles of the pulverized material are directed outwardly by the vortex flow where they contact the inner cylindrical surface of the separation drum and are then deposited at the bottom thereof for easy collection and removal. The pulverized material drying apparatus is particularly adapted for drying coal fines and facilitates the recovery of the pulverized coal. 2 figs.

Carlson, L.W.

1984-08-16T23:59:59.000Z

418

Numerical studies of gravity effects in two-phase reservoirs  

DOE Green Energy (OSTI)

Numerical studies are performed to investigate the effects of localized feed zones on the pressure transients in two-phase reservoirs. It is shown that gravity effects can significantly affect the pressure transients, because of the large difference in the density of liquid water and vapor. Pressure transients for shallow and deep feed zones and the resulting fluid flow patterns are discussed.

Bodvarsson, G.S.; Cox, B.L.

1986-06-01T23:59:59.000Z

419

High efficiency vapor-fed AMTEC system for direct conversion. Final report  

DOE Green Energy (OSTI)

The Alkali Metal Thermal to Electric Converter (AMTEC) is a high temperature, high efficiency system for converting thermal to electrical energy, with no moving parts. It is based on the unique properties of {beta}{double_prime}-alumina solid electrolyte (BASE), which is an excellent conductor of sodium ions, but an extremely poor conductor of electrons. When the inside of the BASE is maintained at a higher temperature and pressure, a concentration gradient is created across the BASE. Electrons and sodium atoms cannot pass through the BASE. However, the sodium atoms are ionized, and the sodium ions move through the BASE to the lower potential (temperature) region. The electrons travel externally to the AMTEC cell, providing power. There are a number of potential advantages to a wick-pumped, vapor-fed AMTEC system when compared with other designs. A wick-pumped system uses capillary forces to passively return liquid to the evaporator, and to distribute the liquid in the evaporator. Since the fluid return is self-regulating, multiple BASE tubes can use a single remote condenser, potentially improving efficiency in advanced AMTEC designs. Since the system is vapor-fed, sodium vapor is supplied at a uniform temperature and flux to the BASE tube, even with non-uniform heat fluxes and temperatures at the evaporator. The primary objective of the Phase 2 program was to develop wick-pumped AMTEC cells. During the program, procedures to fabricate wicks with smaller pore sizes were developed, to allow operation of an AMTEC cell at 800 C. A revised design was made for a High-Temperature, Wick-Fed AMTEC cell. In addition to the smaller wick pore size, several other changes were made to increase the cell efficiency: (1) internal artery return of condensate; (2) high temperature electrical feedthrough; and (3) separate heat pipe for providing heat to the BASE.

Anderson, W.G.; Bland, J.J.

1997-05-23T23:59:59.000Z

420

An advanced vapor-compression desalination system  

E-Print Network (OSTI)

Currently, the two dominant desalination methods are reverse osmosis (RO) and multi-stage flash (MSF). RO requires large capital investment and maintenance, whereas MSF is too energy intensive. An innovative vapor-compression desalination system is developed in this study. A comprehensive mathematical model for the heat exchanger/evaporator is described. The literature indicates that extraordinarily high overall heat transfer coefficients for the evaporator are possible at selected operating conditions that employ dropwise condensation in the steam side and pool boiling in the liquid side. A smooth titanium surface is chosen to promote dropwise condensation and to resist corrosion. To maximize energy efficiency, a combined-cycle cogeneration scheme is employed composed of a gas turbine, a heat recovery boiler, and a steam turbine that drive a compressor. The combined-cycle power source is oversized relative to the needs of the compressor. The excess power is converted to electricity and sold to the open market. A three-effect evaporator is employed. It is fed with seawater, assumed to be 3.5% salt. Boiling brine (7% salt) is in the low pressure side of the heat exchanger and condensing steam is in the high-pressure side of the heat exchanger. The condensing steam flows at 1.52 m/s (5 ft/s), which maximizes the heat transfer coefficient. The plant is sized to produce 37,854 m3/d (10 mill gal/day) and is assumed to be financed with a 5%, 30-yr municipal bond. Two economic cases were emphasized: the United States and the Middle East. For the United States, the fuel costs $5/GJ ($5.27/mill Btu) with the latent heat exchanger at ( ) 1.11 K 2.00 F T � = ° . The required compressor energy is 14 MJ/m3 (14.7 kW h/thous gal). The capital cost for the U.S. is $884 d/m3 ($3,342/thous gal) and the delivered water selling price is $0.47/m3 ($1.79/thous/gal). For the Middle East, the fuel costs $0.5/GJ ($0.53/mill Btu) with the latent heat exchanger at K T 33 . 3 = � ( ) F 00 . 6 ° . The required compressor energy is 26 MJ/m3 (27.3 kW h/thous gal). ). The capital cost for the Middle East is $620 d/m3 ($2,344/thous gal), and the delivered water selling price is $0.25/m3 ($0.95/thous/gal). In all cases, the water selling price is attractive relative to competing technologies.

Lara Ruiz, Jorge Horacio Juan

2005-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "vapor phase epitaxy" 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

PHASE DETECTOR  

DOE Patents (OSTI)

A phase detector circuit is described for use at very high frequencies of the order of 50 megacycles. The detector circuit includes a pair of rectifiers inverted relative to each other. One voltage to be compared is applied to the two rectifiers in phase opposition and the other voltage to be compared is commonly applied to the two rectifiers. The two result:ng d-c voltages derived from the rectifiers are combined in phase opposition to produce a single d-c voltage having amplitude and polarity characteristics dependent upon the phase relation between the signals to be compared. Principal novelty resides in the employment of a half-wave transmission line to derive the phase opposing signals from the first voltage to be compared for application to the two rectifiers in place of the transformer commonly utilized for such purpose in phase detector circuits for operation at lower frequency.

Kippenhan, D.O.

1959-09-01T23:59:59.000Z

422

Equilibrium predictions of the role of organosilicon compounds in the chemical vapor deposition of silicon carbide  

DOE Green Energy (OSTI)

Equilibrium calculations are reported for a range of conditions used to deposit silicon carbide (SiC) from Si-C-H mixtures such as those using SiH{sub 4}, C{sub 2}H{sub 4}, and H{sub 2} as reactants. Included are 37 molecules containing both silicon and carbon, allowing as assessment to be made of the importance of organosilicon species to the deposition process. The results indicate that Si{sub 2}C and SiCH{sub 2} may contribute to epitaxial SiC deposition and that formation of these and other organosilicon species is favored by low H{sub 2} concentrations. In addition, simulations of gas-phase equilibria expected under low-pressure, low-temperature conditions show that some organosilicon radicals that are kinetically favored are also thermodynamically favored. These include SiC{sub 2}, SiCCH, and HSiCCH, which could results from the reactor of SiH{sub 2} with unsaturated reactants such as C{sub 2}H{sub 2}. The results suggest that combining an inert carrier gas with an excess of a surface-reactive hydrocarbon such as C{sub 2}H{sub 2} could increase deposition rates without forming silicon-rich deposits. 25 refs.

Allendorf, M.D.

1992-06-01T23:59:59.000Z

423

PHASE BEHAVIOR OF LIGHT GASES IN HYDROCARBON AND AQUEOUS SOLVENTS  

Science Conference Proceedings (OSTI)

Under previous support from the Department of Energy, an experimental facility has been established and operated to measure valuable vapor-liquid equilibrium data for systems of interest in the production and processing of coal fluids. To facilitate the development and testing of models for prediction of the phase behavior for such systems, we have acquired substantial amounts of data on the equilibrium phase compositions for binary mixtures of heavy hydrocarbon solvents with a variety of supercritical solutes, including hydrogen, methane, ethane, carbon monoxide, and carbon dioxide. The present project focuses on measuring the phase behavior of light gases and water in Fischer-Tropsch (F-T) type solvents at conditions encountered in indirect liquefaction processes and evaluating and developing theoretically-based correlating frameworks to predict the phase behavior of such systems. Specific goals of the proposed work include (a) developing a state-of-the-art experimental facility to permit highly accurate measurements of equilibrium phase compositions (solubilities) of challenging F-T systems, (b) measuring these properties for systematically-selected binary, ternary and molten F-T wax mixtures to provide critically needed input data for correlation development, (c) developing and testing models suitable for describing the phase behavior of such mixtures, and (d) presenting the modeling results in generalized, practical formats suitable for use in process engineering calculations. During the present period, the Park-Gasem-Robinson (PGR) equation of state (EOS) has been modified to improve its volumetric and equilibrium predictions. Specifically, the attractive term of the PGR equation was modified to enhance the flexibility of the model, and a new expression was developed for the temperature dependence of the attractive term in this segment-segment interaction model. The predictive capability of the modified PGR EOS for vapor pressure, and saturated liquid and vapor densities was evaluated for selected normal paraffins, normal alkenes, cyclo-paraffins, light aromatics, argon, carbon dioxide and water. The generalized EOS constants and substance-specific characteristic parameters in the modified PGR EOS were obtained from the pure component vapor pressures, and saturated liquid and vapor molar volumes. The calculated phase properties were compared to those of the Peng-Robinson (PR), the simplified-perturbed-hard-chain theory (SPHCT) and the original PGR equations. Generally, the performance of the proposed EOS was better than the PR, SPHCT and original PGR equations in predicting the pure fluid properties (%AAD of 1.3, 2.8 and 3.7 for vapor pressure, saturated liquid and vapor densities, respectively).

KHALED A.M. GASEM; ROBERT L. ROBINSON, JR.

1998-08-31T23:59:59.000Z

424

Physicochemical Perturbations of Phase Equilibriums  

E-Print Network (OSTI)

The alternative approach to the displacement of gas/liquid equilibrium is developed on the basis of the Clapeyron equation. The phase transition in the system with well-established properties is taken as a reference process to search for the parameters of phase transition in the perturbed equilibrium system. The main equation, derived in the framework of both classical thermodynamics and statistical mechanics, establishes a correlation between variations of enthalpies of evaporation, \\Delta (\\Delta H), which is induced by perturbations, and the equilibrium vapor pressures. The dissolution of a solute, changing the surface shape, and the effect of the external field of adsorbents are considered as the perturbing actions on the liquid phase. The model provides the unified method for studying (1) solutions, (2) membrane separations (3) surface phenomena, and (4) effect of the adsorption field; it leads to the useful relations between \\Delta (\\Delta H), on the one hand, and the osmotic pressures, the Donnan potential, the surface curvature, and the pore structure, on the other hand. The value of \\Delta(\\Delta H) has a clear physical meaning and gives a new insight into our understanding of the apparently different phenomena. The model is applicable if the change between entropies of the comparable gas phases is far more than the difference between entropies of the liquid phases.

Vladimir Kh. Dobruskin

2010-06-13T23:59:59.000Z

425

Low temperature photochemical vapor deposition of alloy and mixed metal oxide films  

DOE Patents (OSTI)

Method and apparatus for formation of an alloy thin film, or a mixed metal oxide thin film, on a substrate at relatively low temperatures. Precursor vapor(s) containing the desired thin film constituents is positioned adjacent to the substrate and irradiated by light having wavelengths in a selected wavelength range, to dissociate the gas(es) and provide atoms or molecules containing only the desired constituents. These gases then deposit at relatively low temperatures as a thin film on the substrate. The precursor vapor(s) is formed by vaporization of one or more precursor materials, where the vaporization temperature(s) is selected to control the ratio of concentration of metals present in the precursor vapor(s) and/or the total precursor vapor pressure.

Liu, David K. (San Pablo, CA)

1992-01-01T23:59:59.000Z

426

Effect of pressure on the phase behavior and structure of water confined between nanoscale hydrophobic and hydrophilic plates  

E-Print Network (OSTI)

.1 GPa, the system crystallizes into a bilayer ice. A P-d phase diagram showing the vapor, liquid, and bilayer ice phases is proposed. When water is confined by hydrophilic hydroxylated silica platesEffect of pressure on the phase behavior and structure of water confined between nanoscale

427

Method utilizing laser-processing for the growth of epitaxial p-n junctions  

DOE Patents (OSTI)

This invention is a new method for the formation of epitaxial p-n junctions in silicon. The method is relatively simple, rapid, and reliable. It produces doped epitaxial layers which are of well-controlled thickness and whose electrical properties are satisfactory. An illustrative form of the method comprises co-depositing a selected dopant and amorphous silicon on a crystalline silicon substrate to form a doped layer of amorphous silicon thereon. This layer then is irradiated with at least one laser pulse to generate a melt front which moves through the layer, into the silicon body to a depth effecting melting of virginal silicon, and back to the surface of the layer. The method may be conducted with dopants (e.g., boron and phosphorus) whose distribution coefficients approximate unity.

Young, R.T.; Narayan, J.; Wood, R.F.

1979-11-23T23:59:59.000Z

428

Validation of TES Temperature and Water Vapor Retrievals with ARM  

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

Validation of TES Temperature and Water Vapor Retrievals with ARM Validation of TES Temperature and Water Vapor Retrievals with ARM Observations Cady-Pereira, Karen Atmospheric and Environmental Research, Inc. Shephard, Mark Atmospheric and Environmental Research, Inc. Clough, Shepard Atmospheric and Environmental Research Mlawer, Eli Atmospheric & Environmental Research, Inc. Turner, David University of Wisconsin-Madison Category: Atmospheric State and Surface The primary objective of the TES (Tropospheric Emission Spectrometer) instrument on the Aura spacecraft is the retrieval of trace gases, especially water vapor and ozone. The TES retrievals extremely useful for global monitoring of the atmospheric state, but they must be validated. The ARM sites are well instrumented and provide continuous measurements, which

429

High temperature vapor pressure and the critical point of potassium  

SciTech Connect

The vapor pressure of potassium was experimentally determined from 2100 deg F up to-its critical temperature. An empirical equation of the form ln P = A + B/T + C ln T + DT/sup 1.5/ was found to best fit the data. A critical pressure of 2378.2 plus or minus 4.0 psia (161.79 plus or minus 0.27 ata) was measured. The corresponding critical temperature, extrapolated from the pressure-- temperature curve, is 4105.4 plus or minus 5 deg R (2280.8 plus or minus 3 deg K). The technique employed was tae pressure tube method developed earlier in this laboratory and used for determining the vapor pressure of rubidium and cesium. This method measures tae critical pressure directly, as well as the vapor pressure st lower temperatures. (4 tables, 6 figures, 26 references) (auth)

Jerez, W.R.; Bhise, V.S.; Das Gupta, S.; Bonilla, C.F.

1973-01-01T23:59:59.000Z

430

Atmospheric Precorrected Differential Absorption technique to retrieve columnar water vapor  

Science Conference Proceedings (OSTI)

Differential absorption techniques are suitable to retrieve the total column water vapor contents from imaging spectroscopy data. A technique called Atmospheric Precorrected Differential Absorption (APDA) is derived directly from simplified radiative transfer equations. It combines a partial atmospheric correction with a differential absorption technique. The atmospheric path radiance term is iteratively corrected during the retrieval of water vapor. This improves the results especially over low background albedos. The error of the method for various ground reflectance spectra is below 7% for most of the spectra. The channel combinations for two test cases are then defined, using a quantitative procedure, which is based on MODTRAN simulations and the image itself. An error analysis indicates that the influence of aerosols and channel calibration is minimal. The APDA technique is then applied to two AVIRIS images acquired in 1991 and 1995. The accuracy of the measured water vapor columns is within a range of {+-}5% compared to ground truth radiosonde data.

Schlaepfer, D.; Itten, K.I. [Univ. of Zuerich (Switzerland). Dept. of Geography] [Univ. of Zuerich (Switzerland). Dept. of Geography; Borel, C.C. [Los Alamos National Lab., NM (United States)] [Los Alamos National Lab., NM (United States); Keller, J. [Paul Scherrer Inst., Villigen (Switzerland)] [Paul Scherrer Inst., Villigen (Switzerland)

1998-09-01T23:59:59.000Z

431

Interactions between Liquid-Wall Vapor and Edge Plasmas  

DOE Green Energy (OSTI)

The use of liquid walls for fusion reactors could help solve problems associated with material erosion from high plasma heat-loads and neutronic activation of structures. A key issue analyzed here is the influx of impurity ions to the core plasma from the vapor of liquid side-walls. Numerical 2D transport simulations are performed for a slab geometry which approximates the edge region of a reactor-size tokamak. Both lithium vapor (from Li or SnLi walls) and fluorine vapor (from Flibe walls) are considered for hydrogen edge-plasmas in the high- and low-recycling regimes. It is found that the minimum influx is from lithium with a low-recycling hydrogen plasma, and the maximum influx occurs for fluorine with a high-recycling hydrogen plasma.

Rognlien, T D; Rensink, M E

2000-05-25T23:59:59.000Z

432

Intermediate Vapor Expansion Distillation and Nested Enrichment Cascade Distillation  

E-Print Network (OSTI)

Although it is known that incorporating an intermediate reboiler or reflux condenser in a distillation column will improve column efficiency by 15 to 100%, there has been little use of this technique to date." Intermediate vapor compression heat pumping was recently introduced as one practical means of achieving this benefit. Introduced in this paper are two new means having added advantages over compression: intermediate vapor expansion heat pumping, and nested enrichment cascades. In both cases the efficiency advantage is obtained without requiring import of shaft work. With intermediate vapor expansion, the expander is more efficient and less costly than the compressor which achieves comparable improvement in distillation efficiency. With the "nested enrichment" technique, the increased efficiency is obtained without requiring either compressors or expanders.

Erickson, D. C.

1986-06-01T23:59:59.000Z

433

A new comprehensive semiempirical approach to calculate three-phase water/hydrocarbons equilibria  

E-Print Network (OSTI)

A new comprehensive semiempirical approach (CSA) has been developed to calculate three-phase water/hydrocarbons equilibria. It uses both laboratory data (stagewise isochoric distillation data) and Peng-Robinson EOS. It considers mutual solubility between water and hydrocarbons. The CSA calculates phase equilibria by applying the thermodynamic equalities between phases and material balance of the systems. The CSA also includes a self-tuning algorithm that allows the user to tune the input parameters, i.e. vapor phase composition (vi). In this study, the CSA has been used to run the data from Billman (1989) and Beladi (1995). These data include two ternary systems of n-heptane/n-dodecane/water, for which their initial overall compositions are different, and one ternary system of n-decane/n-pentadecane/water. The vapor phase composition (yi) data has been tuned to satisfy the following material balance equation: [] The approachhas been verified by comparing the calculated vapor phase composition (yi calc ) with yi data and yi tuning value. They all matched each other in some range of data uncertainty. The data uncertainty ranges from 0.62 to 60.6%. The oleic phase composition can be used to show that solubility of water in oleic phase cannot be neglected. It is shown in this study that vapor-oleic three-phase K-values are slightly dependent upon composition. It is also shown that the lighter the hydrocarbon component, the higher the vapor-oleic three-phase K-values are. The aqueous phase composition in this study shows that solubility of hydrocarbons in the aqueous phase is insignificant,

Tandia, Bagus Krisna

1995-01-01T23:59:59.000Z

434

Atmospheric-Pressure Chemical Vapor Deposition of Iron Pyrite Thin Films  

Science Conference Proceedings (OSTI)

Iron pyrite (cubic FeS{sub 2}) is a promising candidate absorber material for earth-abundant thin-film solar cells. In this report, single-phase, large-grain, and uniform polycrystalline pyrite thin films are fabricated on glass and molybdenum-coated glass substrates by atmospheric-pressure chemical vapor deposition (AP-CVD) using the reaction of iron(III) acetylacetonate and tert-butyl disulfide in argon at 300 C, followed by sulfur annealing at 500--550 C to convert marcasite impurities to pyrite. The pyrite-marcasite phase composition depends strongly on the concentration of sodium in the growth substrate and the sulfur partial pressure during annealing. Phase and elemental composition of the films are characterized by X-ray diffraction, Raman spectroscopy, Auger electron spectroscopy, secondary ion mass spectrometry, Rutherford backscattering spectrometry, and X-ray photoelectron spectroscopy. The in-plane electrical properties are surprisingly insensitive to phase and elemental impurities, with all films showing p-type, thermally activated transport with a small activation energy ({approx}30 meV), a room- temperature resistivity of {approx}1 {Omega} cm, and low mobility. These ubiquitous electrical properties may result from robust surface effects. These CVD pyrite thin films are well suited to fundamental electrical studies and the fabrication of pyrite photovoltaic device stacks.

Berry, Nicholas; Cheng, Ming; Perkins, Craig L.; Limpinsel, Moritz; Hemminger, John C.; Law, Matt (NREL); (UCI)

2012-10-23T23:59:59.000Z

435

Fabrication of precision high quality facets on molecular beam epitaxy material  

DOE Patents (OSTI)

Fabricating mirrored vertical surfaces on semiconductor layered material grown by molecular beam epitaxy (MBE). Low energy chemically assisted ion beam etching (CAIBE) is employed to prepare mirrored vertical surfaces on MBE-grown III-V materials under unusually low concentrations of oxygen in evacuated etching atmospheres of chlorine and xenon ion beams. UV-stabilized smooth-surfaced photoresist materials contribute to highly vertical, high quality mirrored surfaces during the etching.

Petersen, Holly E. (Tracy, CA); Goward, William D. (Antioch, CA); Dijaili, Sol P. (Moraga, CA)

2001-01-01T23:59:59.000Z

436

Low-temperature grown graphene films by using molecular beam epitaxy  

Science Conference Proceedings (OSTI)

Complete graphene film is prepared by depositing carbon atoms directly on Cu foils in a molecular beam epitaxy chamber at 300 Degree-Sign C. The Raman spectrum of the film has indicated that high-quality few-layer graphene is obtained. With back-gated transistor architecture, the characteristic current modulation of graphene transistors is observed. Following the similar growth procedure, graphitization is observed at room temperature, which is consistent with the molecular dynamics simulations of graphene growth.

Lin, Meng-Yu [Institute of Electronics, National Taiwan University, Taipei, Taiwan (China); Research Center for Applied Sciences, Academia Sinica, Nankang, Taipei, Taiwan (China); Guo, Wei-Ching; Wang, Pro-Yao [Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung, Taiwan (China); Wu, Meng-Hsun [College of Photonics, National Chiao-Tung University, Tainan, Taiwan (China); Liu, Te-Huan; Chang, Chien-Cheng [Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan (China); Pao, Chun-Wei; Lin, Shih-Yen [Research Center for Applied Sciences, Academia Sinica, Nankang, Taipei, Taiwan (China); Lee, Si-Chen [Institute of Electronics, National Taiwan University, Taipei, Taiwan (China)

2012-11-26T23:59:59.000Z

437

Vapor sampling of the headspace of radioactive waste storage tanks  

DOE Green Energy (OSTI)

This paper recants the history of vapor sampling in the headspaces of radioactive waste storage tanks at Hanford. The first two tanks to receive extensive vapor pressure sampling were Tanks 241-SY-101 and 241-C-103. At various times, a gas chromatography, on-line mass spectrometer, solid state hydrogen monitor, FTIR, and radio acoustic ammonia monitor have been installed. The head space gas sampling activities will continue for the next few years. The current goal is to sample the headspace for all the tanks. Some tank headspaces will be sampled several times to see the data vary with time. Other tanks will have continuous monitors installed to provide additional data.

Reynolds, D.A., Westinghouse Hanford

1996-05-22T23:59:59.000Z

438

Collimated Blue and Infrared Beams Generated by Two-Photon Excitation in Rb Vapor  

E-Print Network (OSTI)

Utilizing two-photon excitation in hot Rb vapor we demonstrate the generation of collimated optical fields at 420 nm and 1324 nm. Input laser beams at 780 nm and 776 nm enter a heated Rb vapor cell collinear and circularly polarized, driving Rb atoms to the $5D_{5/2}$ state. Under phase-matching conditions coherence among the $5S_{1/2}\\rightarrow 5P_{3/2}\\rightarrow 5D_{5/2} \\rightarrow 6P_{3/2}$ transitions produces a blue (420 nm) beam by four-wave mixing. We also observe a forward and backward propagating IR (1324 nm) beam, due to cascading decays through the $6S_{1/2}\\rightarrow 5P_{1/2}$ states. Power saturation of the generated beams is investigated by scaling the input powers to greater than 200 mW, resulting in a coherent blue beam of 9.1 mW power, almost an order of magnitude larger than previously achieved. We measure the dependences of both beams in relation to the Rb density, the frequency detuning between Rb ground state hyperfine levels, and the input laser intensities.

Sell, J F; DePaola, B D; Knize, R J

2013-01-01T23:59:59.000Z

439

Process for depositing epitaxial alkaline earth oxide onto a substrate and structures prepared with the process  

Science Conference Proceedings (OSTI)

A process and structure involving a silicon substrate utilize molecular beam epitaxy (MBE) and/or electron beam evaporation methods and an ultra-high vacuum facility to grow a layup of epitaxial alkaline earth oxide films upon the substrate surface. By selecting metal constituents for the oxides and in the appropriate proportions so that the lattice parameter of each oxide grown closely approximates that of the substrate or base layer upon which oxide is grown, lattice strain at the film/film or film/substrate interface of adjacent films is appreciably reduced or relieved. Moreover, by selecting constituents for the oxides so that the lattice parameters of the materials of adjacent oxide films either increase or decrease in size from one parameter to another parameter, a graded layup of films can be grown (with reduced strain levels therebetween) so that the outer film has a lattice parameter which closely approximates that of, and thus accomodates the epitaxial growth of, a pervoskite chosen to be grown upon the outer film.

McKee, Rodney A. (Kingston, TN); Walker, Frederick J. (Oak Ridge, TN)

1996-01-01T23:59:59.000Z

440

Homobuffer thickness effect on the background electron carrier concentration of epitaxial ZnO thin films  

Science Conference Proceedings (OSTI)

Epitaxial ZnO thin films were grown on r-plane sapphire substrates using plasma-assisted molecular-beam epitaxy. ZnO homobuffer layers grown at a lower temperature were introduced to improve the crystallinity of the top ZnO thin films. Thicker homobuffer layers lead to better crystallinity of the subsequent epitaxial ZnO thin films due to the strain relaxation effect. Residual background electron carrier concentration in these undoped ZnO thin films first decreases, then increases as the buffer layer thickness increases from {approx}1 to 30 nm, with a minimum electron concentration of {approx}1x10{sup 17} cm{sup -3} occurring in ZnO homobuffer of {approx}5 nm. These results demonstrate that the optimized ZnO homobuffer thickness to achieve both good ZnO crystallinity and low residual electron concentration is determined by the relative electron carrier concentration ratios and mobility ratios between the buffer and epi-ZnO layers.

Yang, Z.; Zhou, H. M.; Li, L.; Zhao, J. Z.; Liu, J. L. [Department of Electrical Engineering, Quantum Structures Laboratory, University of California, Riverside, California 92521 (United States); Chen, W. V.; Yu, P. K. L. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States)

2010-09-15T23:59:59.000Z

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441

The Atomic Vapor Laser Isotope Separation Program. [Atomic Vapor Laser Isotope Separation (AVLIS) Program  

SciTech Connect

This report provides the finding and recommendations on the audit of the Atomic Vapor Laser Isotope Separation (AVLIS) program. The status of the program was assessed to determine whether the Department was achieving objectives stated in its January 1990 Plan for the Demonstration, Transition and Deployment of AVLIS Technology. Through Fiscal Year 1991, the Department had spent about $1.1 billion to develop AVLIS technology. The January 1990 plan provided for AVLIS to be far enough along by September to enable the Department to make a determination of the technical and economic feasibility of deployment. However, the milestones needed to support that determination were not met. An estimated $550 million would be needed to complete AVLIS engineering development and related testing prior to deployment. The earliest possible deployment date has slipped to beyond the year 2000. It is recommended that the Department reassess the requirement for AVLIS in light of program delays and changes that have taken place in the enrichment market since January 1990. Following the reassessment, a decision should be made to either fully support and promote the actions needed to complete AVLIS development or discontinue support for the program entirely. Management's position is that the Department will successfully complete the AVLIS technology demonstration and that the program should continue until it can be transferred to a Government corporation. Although the auditors recognize that AVLIS may be transferred, there are enough technical and financial uncertainties that a thorough assessment is warranted.

Not Available

1992-11-09T23:59:59.000Z

442

Development of a wet vapor homogeneous liquid metal MHD power system. Final report  

DOE Green Energy (OSTI)

A feasibility study for the approval of liquid metal seeds recovery from a liquid metal vapor-inert gas mixture was conducted and presented in this report. The research activity included background studies on processes relating to mixing stream condenser performance, parametric studies and its experimental validation. The condensation process under study includes mass transfer phenomena combined with heat transfer and phase change. Numerical methods were used in order to solve the dynamic equations and to carry out the parametric study as well as the experimental data reduction. The MSC performance is highly effected by droplet diameter, thus the possibility of atomizing liquid metals were experimentally investigated. The results are generalized and finally used for a set of recommendations by which the recovery of seeds is expected to be feasible.

Branover, H.; Unger, Y.; El-Boher, A.; Schweitzer, H.

1991-09-01T23:59:59.000Z

443

Computation of Infrared Cooling Rates in the Water Vapor Bands  

Science Conference Proceedings (OSTI)

A fast but accurate method for calculating the infrared radiative terms due to water vapor has been developed. It makes use of the behavior in the far wings of absorption lines to scale transmission along an inhomogencous path to an equivalent ...

Ming Dah Chou; Albert Arking

1980-04-01T23:59:59.000Z

444

Probing Hurricanes with Stable Isotopes of Rain and Water Vapor  

Science Conference Proceedings (OSTI)

Rain and water vapor were collected during flights in Hurricanes Olivia (1994), Opal (1995), Marilyn (1995), and Hortense (1995) and analyzed for their stable isotopic concentrations, or ratios, H218O:H2O and HDO:H2O. The spatial patterns and ...

Stanley Gedzelman; James Lawrence; John Gamache; Michael Black; Edward Hindman; Robert Black; Jason Dunion; Hugh Willoughby; Xiaoping Zhang

2003-06-01T23:59:59.000Z

445

Observation of Water Vapor Greenhouse Absorption over the Gulf of Mexico Using Aircraft and Satellite Data  

Science Conference Proceedings (OSTI)

Through its interaction with radiation, water vapor provides an important link between the ocean and atmosphere. One way this occurs is through the greenhouse effect; observations of water vapor greenhouse absorption in the Gulf of Mexico during ...

David Marsden; Francisco P. J. Valero

2004-03-01T23:59:59.000Z

446

Investigation of Turbulent Processes in the Lower Troposphere with Water Vapor DIAL and Radar–RASS  

Science Conference Proceedings (OSTI)

High-resolution water vapor and wind measurements in the lower troposphere within the scope of the Baltic Sea Experiment (BALTEX) are presented. The measurements were performed during a field campaign with a new water vapor differential ...

V. Wulfmeyer

1999-04-01T23:59:59.000Z

447

Method and apparatus to measure vapor pressure in a flow system  

DOE Patents (OSTI)

The present invention is directed to a method for determining, by a condensation method, the vapor pressure of a material with a known vapor pressure versus temperature characteristic, in a flow system particularly in a mercury isotope enrichment process.

Grossman, Mark W. (Belmont, MA); Biblarz, Oscar (Swampscott, MA)

1991-01-01T23:59:59.000Z

448

Influence of a Tropical Island Mountain on Solar Radiation, Air Temperature and Vapor Pressure  

Science Conference Proceedings (OSTI)

Measured solar radiation, air temperature, and water vapor pressure at 17 stations on the northwest flank of Haleakala, Maui, Hawaii are compared with modeled clear day solar radiation and free atmosphere air temperature and water vapor pressure. ...

Dennis Nullet

1989-03-01T23:59:59.000Z

449

Modes and Mechanisms of Global Water Vapor Variability over the Twentieth Century  

Science Conference Proceedings (OSTI)

The modes and mechanisms of the annual water vapor variations over the twentieth century are investigated based on a newly developed twentieth-century atmospheric reanalysis product. It is found that the leading modes of global water vapor ...

Liping Zhang; Lixin Wu; Bolan Gan

2013-08-01T23:59:59.000Z

450

Water Vapor Transport and the Production of Precipitation in the Eastern Fertile Crescent  

Science Conference Proceedings (OSTI)

The study presented here attempts to quantify the significance of southerly water vapor fluxes on precipitation occurring in the eastern Fertile Crescent region. The water vapor fluxes were investigated at high temporal and spatial resolution by ...

J. P. Evans; R. B. Smith

2006-12-01T23:59:59.000Z

451

Automated Retrievals of Water Vapor and Aerosol Profiles from an Operational Raman Lidar  

Science Conference Proceedings (OSTI)

Automated routines have been developed to derive water vapor mixing ratio, relative humidity, aerosol extinction and backscatter coefficient, and linear depolarization profiles, as well as total precipitable water vapor and aerosol optical ...

D. D. Turner; R. A. Ferrare; L. A. Heilman Brasseur; W. F. Feltz; T. P. Tooman

2002-01-01T23:59:59.000Z

452

Tropical Water Vapor and Cloud Feedbacks in Climate Models: A Further Assessment Using Coupled Simulations  

Science Conference Proceedings (OSTI)

By comparing the response of clouds and water vapor to ENSO forcing in nature with that in Atmospheric Model Intercomparison Project (AMIP) simulations by some leading climate models, an earlier evaluation of tropical cloud and water vapor ...

De-Zheng Sun; Yongqiang Yu; Tao Zhang

2009-03-01T23:59:59.000Z

453

A Comparison of Water Vapor Measurements Made by Raman Lidar and Radiosondes  

Science Conference Proceedings (OSTI)

This paper examines the calibration characteristics of the NASA/GSFC Raman water vapor lidar during three field experiments that occurred between 1991 and 1993. The lidar water vapor profiles are calibrated using relative humidity profiles ...

R. A. Ferrare; S. H. Melfi; D. N. Whiteman; K. D. Evans; F. J. Schmidlin; D. O'C. Starr

1995-12-01T23:59:59.000Z

454

Heat transfer during film condensation of potassium vapor on a horizontal plate  

E-Print Network (OSTI)

The object of the investigation is to analyze the following two features of heat transfer during condensation of potassium vapor: a. Heat transfer during film condensation of a pure saturated potassium vapor on a horizontal ...

Meyrial, Paul M.

1968-01-01T23:59:59.000Z

455

Chemical vapor deposition thin films as biopassivation coatings and directly patternable dielectrics  

E-Print Network (OSTI)

Organosilicon thin films deposited by pulsed plasma-enhanced chemical vapor deposition (PPECVD) and hot-filament chemical vapor deposition (HFCVD) were investigated as potential biopassivation coatings for neural probes. ...

Pryce Lewis, Hilton G. (Hilton Gavin), 1973-

2001-01-01T23:59:59.000Z

456

Determination of concentration-dependent dispersion of propane in vapor extraction of heavy oil.  

E-Print Network (OSTI)

??Vapex (vapor extraction) is a solvent-based non-thermal in-situ heavy oil recovery process. In Vapex process, a vaporized hydrocarbon solvent is injected into an upper horizontal… (more)

Abukhalifeh, Hadil

2010-01-01T23:59:59.000Z

457

Measurements of the Vapor Pressure of Supercooled Water Using Infrared Spectroscopy  

Science Conference Proceedings (OSTI)

Measurements are presented of the vapor pressure of supercooled water utilizing infrared spectroscopy, which enables unambiguous verification that the authors’ data correspond to the vapor pressure of liquid water, not a mixture of liquid water ...

Will Cantrell; Eli Ochshorn; Alexander Kostinski; Keith Bozin

2008-09-01T23:59:59.000Z

458

Phase Transformations  

Science Conference Proceedings (OSTI)

Aug 9, 2013 ... O. Advanced Neutron and Synchrotron Studies of Materials: Phase .... We will describe recent advances at the Advanced Photon Source in ... Finally, we will describe upgrade plans for microdiffraction capabilities at the APS.

459

Plasma Kinetics in Electrical Discharge in Mixture of Air, Water and Ethanol Vapors for Hydrogen Enriched Syngas Production  

E-Print Network (OSTI)

The complex theoretical and experimental investigation of plasma kinetics of the electric discharge in the mixture of air and ethanol-water vapors is carried out. The discharge was burning in the cavity, formed by air jets pumping between electrodes, placed in aqueous ethanol solution. It is found out that the hydrogen yield from the discharge is maximal in the case when ethanol and water in the solution are in equal amounts. It is shown that the hydrogen production increases with the discharge power and reaches the saturation at high value. The concentrations of the main stable gas-phase components, measured experimentally and calculated numerically, agree well in the most cases.

Shchedrin, A I; Ryabtsev, A V; Chernyak, V Ya; Yukhymenko, V V; Olszewski, S V; Naumov, V V; Prysiazhnevych, I V; Solomenko, E V; Demchina, V P; Kudryavtsev, V S

2008-01-01T23:59:59.000Z

460

Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System  

DOE Green Energy (OSTI)

This report summarizes work performed on this project from April 2005 through September 2005. In previous work, a series of laboratory scale experiments were conducted to determine the feasibility of using a SMZ system coupled with a VPB to remove and ultimately destroy the organic pollutants found in produced water. Based on the laboratory scale data, a field test of the process was conducted at the McGrath Salt Water Disposal facility in July and August of 2005. The system performed well over repeated feed and regeneration cycles demonstrating the viability of the process for long term operation. Of the BTEX components present in the produced water, benzene had the lowest adsorption affinity for the SMZ and thus controlled the sorption cycle length. Regeneration of the SMZ using air sparging was found to be sufficient in the field to maintain the SMZ adsorption capacity and to allow continuous operation of the system. As expected, the BTEX concentrations in the regeneration off gas stream were initially very high in a given regeneration cycle. However, a granular activated carbon buffering column placed upstream of the VPB reduced the peak BTEX concentrations to acceptable levels for the VPB. In this way, the VPB was able to maintain stable performance over the entire SMZ regeneration period despite the intermittent nature of the feed.

Soondong Kwon; Elaine B. Darby; Li-Jung Chen; Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

2005-09-11T23:59:59.000Z

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461

Vapor Phase Elemental Sulfur Tech Brief DRAFT bbl 08-24  

saturated heated gas into access wells to distribute the gas throughout the site. Solid ... need to inject liquid/fluids). ...

462

Vapor Phase Catalytic Upgrading of Model Biomass-Derived Oxygenate Compounds  

SciTech Connect

When biomass is converted to a liquid bio-oil through pyrolysis, it has a significantly higher oxygen content compared to petroleum fractions. In order to convert the pyrolysis products into infrastructure-compatible fuels, oxygen removal is required. Oxygen removal can be achieved by both hydrotreating (which requires the addition of hydrogen) and decarboxylation or decarbonylation, whereby oxygen is rejected as CO2 and CO, respectively. In the present contribution, a number of catalysts were tested for their activity and selectivity in deoxygenation of model biomass-derived oxygenated compounds (e.g., acetic acid, phenol). Comparison of catalytic activity of materials for different compounds, as well as material characterization results will be discussed. Materials tested will include modified zeolites and supported transition metal catalysts.

Yung, M. M.; Gomez, E.; Kuhn, J. N.

2012-01-01T23:59:59.000Z

463

A NOVEL VAPOR-PHASE PROCESS FOR DEEP DESULFURIZATION OF NAPHTHA/DIESEL  

Science Conference Proceedings (OSTI)

Tier 2 regulations issued by the U.S. Environmental Protection Agency (EPA) require a substantial reduction in the sulfur content of gasoline. Similar regulations have been enacted for the sulfur level in on-road diesel and recently off-road diesel. The removal of this sulfur with existing and installed technology faces technical and economic challenges. These challenges created the opportunity for new emerging technologies. Research Triangle Institute (RTI) with subcontract support from Kellogg Brown & Root, Inc., (KBR) used this opportunity to develop RTI's transport reactor naphtha desulfurization (TReND) process. Starting with a simple conceptual process design and some laboratory results that showed promise, RTI initiated an accelerated research program for sorbent development, process development, and marketing and commercialization. Sorbent development has resulted in the identification of an active and attrition resistant sorbent that has been prepared in commercial equipment in 100 lb batches. Process development has demonstrated both the sulfur removal performance and regeneration potential of this sorbent. Process development has scaled up testing from small laboratory to pilot plant transport reactor testing. Testing in the transport reactor pilot plant has demonstrated the attrition resistance, selective sulfur removal activity, and regeneration activity of this sorbent material. Marketing and commercialization activities have shown with the existing information that the process has significant capital and operating cost benefits over existing and other emerging technologies. The market assessment and analysis provided valuable feedback about the testing and performance requirements for the technical development program. This market analysis also provided a list of potential candidates for hosting a demonstration unit. Although the narrow window of opportunity generated by the new sulfur regulations and the conservative nature of the refining industry slowed progress of the demonstration unit, negotiations with potential partners are proceeding for commercialization of this process.

B.S. Turk; R.P. Gupta; S.K. Gangwal