| Vapor-Phase Infrared Absorptivity Coefficient of Pinacolyl Methylphosphonofluoridate |
May-2009 |
23 pages |
| Authors:
Miles; Alan C Samuels; Ronald W Jr; Barry R Williams; Melissa S Hulet; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD
|
 | We measured the vapor-phase absorptivity coefficient of pinacolyl methylphosphonofluoridate, a chemical warfare agent, (GD, Soman) in the mid-infrared (IR) (4000-550 cm') at a spectral resolution of 0.125 cm1. The GD used in the feedstock was purified by fractional distillation and analyzed by nuclear magnetic resonance, gas chromatography (GC)-mass spectrometry, and GC-IR to verify its purity. We describe the experimental method used to acquire the individual spectra that were used to ... |
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| Vapor-Phase Infrared Absorptivity Coefficient of 2-ChlorovinylDichloroarsine (LEWISITE) |
Jan-2009 |
23 pages |
| Authors:
Miles; Alan C Samuels; H D Durst; Ronald W Jr; Barry R Williams; Melissa S Hulet; Frederic J Berg; Leslie McMahon; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD
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| We measured the vapor-phase absorptivity coefficient of the vesicant chemical warfare agent 2-chlorovinyl dichloroarsine (Lewisite) in the mid-infrared (4000-550/cm) at a spectral resolution of 0.125/cm. The Lewisite used in the feedstock was purified by fractional distillation and analyzed by nuclear magnetic resonance to verify its purity. We describe the experimental method used to acquire the individual spectra that were used to produce the composite spectrum, summarize the statistical uncertainties in ... |
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| Vapor-Phase Infrared Absorptivity Coefficient of Cyclohexyl Isothiocyanate |
01-Jul-2008 |
21 pages |
| Authors:
Miles; Alan C Samuels; Ronald W Jr; Barry R Williams; Melissa S Hulet; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD
|
| We measured the vapor-phase absorptivity coefficient of cyclohexyl isothiocyanate in the mid-infrared (4000-550 cm(-1)) at a spectral resolution of 0.125 cm(-1). The chemical used in the feedstock was subjected to a rigorous analysis by gas chromatography-mass spectrometry, nuclear magnetic resonance, and Karl-Fischer titration to verify its purity. We describe the experimental method used to acquire the individual spectra that were used to produce the composite spectrum and summarize the statistical ... |
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| Vapor-Phase Infrared Absorptivity Coefficient of BIS-(2-Chloroethyl) Sulfide |
01-Jul-2008 |
31 pages |
| Authors:
Alan C Samuels; H D Durst; Barry R Williams; Melissa S Hulet; Ronald W Miles; Frederic J Berg; Leslie McMahon; SCIENCE APPLICATIONS INTERNATIONAL CORP (SAIC) ABINGDON MD
|
| We measured the vapor-phase absorptivity coefficient of the vesicant chemical warfare agent, bis-(2-chloroethyl) sulfide (HD), in the mid-infrared (4000-550/cm) at a spectral resolution of 0.125/cm. The HD used in the feedstock was subjected to a rigorous analysis by gas chromatography (GC) and NMR to verify its purity, and the vapor used to produce the composite spectrum was periodically sampled by GC. In this report, we describe the experimental method employed ... |
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| Carrier Lifetime Dynamics of Epitaxial Layer HVPE Gallium Arsenide Using Time-Resolved Experiments |
MAR 2006 |
79 pages |
| Authors:
Wayne E. Eikenberry; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
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| GaAs is a potential semiconductor material for producing both mid-infrared and terahertz radiation using the new technique of quasi-phase matching in an orientationally patterned GaAs (OP-GaAs) crystal. OP-GaAs is grown using a fast growth process called hydride vapor phase epitaxy (HVPE). Unfortunately, HVPE produces a high number of defects. These defects cause Shockley-Read-Hall recombination rates to dominate over Auger and radiative recombination rates. The carrier lifetime from four OP-GaAs samples ... |
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| Structural Characterization of POSS Siloxane Dimer and Trimer (PREPRINT) |
14 NOV 2005 |
28 pages |
| Authors:
Timothy Haddad; Ashwani Vij; Stan Anderson; Connie Mitchell; Joseph Schwab; Mike Bowers; AIR FORCE RESEARCH LAB EDWARDS AFB CA
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| Ion mobility and molecular modeling methods were used to examine the gas phase conformational properties of POSS (Polyhedral Oligomeric Silsesquioxanes) siloxane oligomers. MALDI generated the sodiated dimers (Cy7T8)2O Na+and (Cp7T8)2O Na+, and the trimer ion [Cy7T8O-Cy8Si8O11-OCy7T8] Na+ (T = SiO1.5, Cy = cyclohexyl, and Cp = cyclopentyl); their collision cross-sections were measured in helium using ion mobility based methods. Experimental results are consistent with one observed conformer for each of ... |
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| A Kinetic Model for Vapor-liquid Flows |
13 JUL 2005 |
7 pages |
| Authors:
Aldo Frezzotti; Livio Gibelli; Silvia Lorenzani; POLITECNICO DI MILANO (ITALY) IST DI MATEMATICA
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| The evaporation of a liquid slab into vacuum is studied by numerical solutions of the Enskog-Vlasov equation for a fluid of spherical molecules interacting by Sutherland potential. The main aim of this work is to obtain the structure of the vapor-liquid interface in non-equilibrium conditions as well as the distribution function of evaporating molecules. The results show that the distribution function of molecules crossing a properly defined vapor-liquid boundary is ... |
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| System for Bulk Growth of Gallium Nitride. Vapor Phase Epitaxy of Gallium Nitride by Gallium Arc Evaporation |
09 MAR 2005 |
17 pages |
| Authors:
Sten J. Heikman; Umesh K. Mishra; CALIFORNIA UNIV SANTA BARBARA
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| A vapor phase growth system intended for the growth of bulk gallium nitride crystals was investigated. Potential advantages of the growth technique are cheap source materials of high purity, no corrosive gasses, and low operating and equipment costs. Ga contained in a crucible was evaporated by an arc discharge between a W-electrode and the Ga surface, and was transported to the growth zone by a carrier gas flowing over the ... |
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| NiAl Bond Coats Made by a Directed Vapor Deposition Approach |
OCT 2004 |
11 pages |
| Authors:
Z.. Yu; D. D. Hass; H. N. Wadley; VIRGINIA UNIV CHARLOTTESVILLE DEPT OF MATERIALS SCIENCE AND ENGINEERING
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| Intermetallic, nickel aluminide alloys are widely used as bond coat materials in thermal barrier coating systems applied to nickel base super alloy components. They are usually synthesized by a solid-state reaction diffusion heat treatment following the chemical vapor deposition of aluminum on the nickel rich substrate. Here, an electron beam directed vapor deposition (EB-DVD) technique is used to simultaneously evaporate nickel and aluminum and then reactively deposit NiAl bond coats ... |
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| Fundamentals of Friction and Vapor Phase Lubrication |
30 JUL 2004 |
14 pages |
| Authors:
Andrew J. Gellman; CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF CHEMICAL ENGINEERING
|
| This is the final report for the three year research program on "Fundamentals of Friction and Vapor Phase Lubrication" conducted at Carnegie Mellon with support from AFOSR grant number F49630-01-1-0069. The report summarizes the program objectives and summarizes the accomplishments and progress of the research towards the development of new methods for high temperature, vapor phase lubrication (VPL), understanding the tribological properties of quasicrystalline films and the development of a ... |
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| Investigation of Structural and Electrical Defects in GaN/AlGaN structures and MODFETs |
2004 |
24 pages |
| Authors:
Hadis Morkoc; VIRGINIA COMMONWEALTH UNIV RICHMOND
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| In this project, main goal was to focus on MODFET structures to understand the sources of improvements and the sources of degradations. In order to reach one of the objectives, the GaN templates grown by MOCVD was followed by c-beam evaporation of Ti layer. By the means of in-situ nitridation in hydrogen and ammonia environment inside the MOCVD system this Ti layer was converted into an effective nano-network of TiN ... |
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| Metal Solvation and Novel Metal-Ligand Interactions in Gas Phase Clusters |
JUL 2003 |
16 pages |
| Authors:
Michael A. Duncan; GEORGIA UNIV RESEARCH FOUNDATION INC ATHENS
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| Gas phase metal-containing clusters are investigated with time-of- flight mass spectrometry, and with both electronic and vibrational laser spectroscopy. Metal ion-molecule complexes of Mg(+) and Ca(+) are studied with electronic photodissociation spectroscopy near the energies of the atomic cation ((2)P-(2)S) resonances. Vibrational spectroscopy of Mg(+) and Al(+) complexes with CO2 are studied with infrared photodissociation spectroscopy near the CO2 asymmetric stretch vibration. The vibrational spectroscopy of metal oxide and carbide ... |
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| Quantitative Vapor-Phase FTIR Spectra of Dimethyl Methylphosphonate and Methyl Salicylate |
APR 2001 |
21 pages |
| Authors:
Barry R. Williams; David E. Tevault; Leonard C. Buettner; EAI CORP ABINGDON MD
|
| This report summarizes the results of initial tests under Contract No. DAAM01-97-D-0015, Task Order No. 0022. The scope of work was to provide preliminary validation of a system for generating quantitative vapor-phase Fourier transform infrared spectra of CW-related compounds using a saturator cell to generate continuous streams of the compounds. The results of the tests with dimethyl methylphosphonate and methyl salicylate showed that the system appears suitable for the purpose. ... |
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| Growth of AlN and GaN Bulk Crystals from the Vapor Phase |
MAR 2001 |
26 pages |
| Authors:
Z. Sitar; R. Schlesser; H. Shin; E. Arkun; R. F. Davis; NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF MATERIALS SCIENCE AND ENGINEERING
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| Prolonged growth of GaN single crystals resulted in decomposed crystals at high ammonia pressures (>430 Torr). Gas composition analysis using quadrupole mass spectrometry revealed that hydrogen concentration in the gas phase increased with increasing ammonia total pressure above 475 Torr in the absence of Ga source and at above 300 Torr in the presence of Ga source. The enhanced decomposition of GaN at higher pressures can be attributed to the ... |
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| Impact of a Ventilated Hood on Heat Stress at High Relative Humidity |
05 AUG 1999 |
5 pages |
| Authors:
Jonathan Kaufman; Gregory Askew; Barry Shender; Kambiz Farahmand; NAVAL AIR WARFARE CENTER AIRCRAFT DIV PATUXENT RIVER MD
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| Heat stress is a major problem associated with use of encapsulating chemical protective garments. Metabolic and externally imposed heat loads can be degrade cognitive and physical performance and prove life-treating if not adequately extracted from within protective clothing ensembles. Two approaches have historically been used to actively remove heat from encapsulating clothing ensembles: (1) vapor phase cooling, where the heat transfer medium is a vapor such as air; and (2) ... |
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| Nasal Heat Probe to Measure Nasal Cavity Heat and Water Vapor Transport |
03 AUG 1999 |
6 pages |
| Authors:
Kambiz Farahmand; Jonathan Kaufman; NAVAL AIR WARFARE CENTER AIRCRAFT DIV PATUXENT RIVER MD
|
| A Nasal-Heat probe was developed to measure intra-airway heat and vapor transfer. The changes in the intra-airway temperature, respiration rate, respiratory heat and water vapor exchange as a result of environmental conditions were easily determined using this device. The humidity profiles generated were closely related to the heat and water vapor exchange. Heat and mass transfer coefficients in the airways were determined from air stream and wall temperatures inside the ... |
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| Growth and Morphology of Er-Doped GaN on Sapphire and Hydride Vapor Phase Epitaxy Substrates |
JUN 1999 |
6 pages |
| Authors:
R. Birkhahn; R. Hudgins; D. Lee; A. J. Steckl; R. J. Molnar; A. Saleh; J. M. Zavada; CINCINNATI UNIV OH NANOELECTRONICS LAB
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| We report the morphological and compositional characteristics and their effect on optical properties of Er-doped GaN grown by solid source molecular beam epitaxy on sapphire and hydride vapor phase epitaxy GaN substrates. The GaN was grown by molecular beam epitaxy on sapphire substrates using solid sources (for Ga, Al, and Er) and a plasma gas source for N2. The emission spectrum of the GaN:Er films consists of two unique narrow ... |
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| Vapor-Phase Lubricants: Nanometer-Scale Mechanisms and Applications to Sub-Micron and Rotating Machinery |
28 FEB 1999 |
9 pages |
| Authors:
Jacqueline Krim; NORTH CAROLINA STATE UNIV AT RALEIGH
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| Vapor-phase lubricants: Nanometer-scale mechanisms and applications to sub-micron machinery was a new program supported by AFOSR involving a set of experimental seeking to explore the nanometer-scale origins of the lubricating properties of vapor-phase lubricants in controlled environmental conditions and well-defined contact geometries. Although such lubricants have been the subject of much research for over 40 years, the atomic-scale details of their lubrication mechanisms are far from being satisfactorily understood. We ... |
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| A Preliminary Study on the Vapor/Mist Phase Lubrication of a Spur Gearbox |
FEB 1999 |
14 pages |
| Authors:
Wilfredo Morales; Robert F. Handschuh; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| Organophosphates have been the primary compounds used in vapor/mist phase lubrication studies involving ferrous bearing material. Experimental results have indicated that the initial formation of an iron phosphate film on a rubbing ferrous surface, followed by the growth (by cationic diffusion) of a lubricious pyrophosphate-type coating over the iron phosphate, is the reason organophosphates work well as vapor/mist phase lubricants. Recent work, however, has shown that this mechanism leads to ... |
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| Gas-Phase Pollutant Decomposition with Non-Thermal Plasmas: Simple Removal Equations and Figures-of Merit |
1999 |
24 pages |
| Authors:
Louis A. Rosocha; LOS ALAMOS NATIONAL LAB NM
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| Non-thermal plasmas (NTPs) are a type of advanced oxidation and reduction technology for treating gas-phase chemical pollutants. Such plasmas are good sources of highly reactive oxidative and reductive species (free radicals and others), e.g., O(P3), OH, N, H, NH, CH, O3, O2 (delta-1), and plasma electrons. Because radical-attack reaction rate constants are very large for many chemical species, entrained pollutants are readily decomposed by NTPs. ... |
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| Compensator Control for Chemical Vapor Deposition Film Growth Using Reduced Order Design Models |
1999 |
30 pages |
| Authors:
G. M. Kepler; H. T. Tran; H. T. Banks; NORTH CAROLINA STATE UNIV AT RALEIGH CENTER FOR RESEARCH IN SCIENTIFIC COMPUTATION
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| We present a summary of investigations on the use of proper orthogonal decomposition (POD) techniques as a reduced basis method for computation of feedback controls and compensators in a high pressure chemical vapor deposition (HPCVD) reactor that includes multiple species and controls, gas phase reactions, and time dependent tracking signals that are consistent with pulsed vapor reactant inputs. Numerical implementation of the model-based feedback control uses a reduced order state ... |
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| Final Comprehensive Technical Report for the Evaluation of Soil Vapor Extraction and Treatment Using Internal Combustion Engine Technology |
JUL 1998 |
67 pages |
| Authors:
Peter R. Guest; PARSONS ENGINEERING SCIENCE INC DENVER CO
|
| Under contract to AFCEE, Parsons ES collected cost and performance data to demonstrate the effectiveness of SVE technology using a modified ICE to extract and destroy fuel hydrocarbons at four Air Force sites. This CTR is intended to summarize the results of the demonstrations by presenting: Analytical data collected during the demonstrations; ICE cost and performance data collected during the demonstrations; An analysis of the ICE vapor treatment efficiency and ... |
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| Ninth International Conference on Metal Organic Vapor Phase Epitaxy (ICMOVPE IX) Held in the Sheraton Grand Hotel, Torrey Pines, CA on June 1-4, 1998 |
01 JUN 1998 |
34 pages |
| Authors:
Scott; MINERALS METALS AND MATERIALS SOCIETY WARRENDALE PA
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| The Ninth International Conference on Metal Organic Vapor Phase Epitaxy (ICMOVPEIX) at the Sheraton Grand Hotel Torrey Pines, CA. The Sponsoring organization was the Minerals, metals and Materials Society. The complete set of presentation abstracts was published in the Journal of Materials. |
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| Water in the Gas Phase |
JUN 1998 |
132 pages |
| Authors:
UNIVERSITE DE MARNE-LA-VALLEE CHAMPS-SUR-MARNE (FRANCE)
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| The Final Proceedings for International Conference on Water in the Gas Phase, 21 June 1998 - 24 June 1998 This is an interdisciplinary conference. Topics include a wide range of scientific aspects of the properties and structure of water and water nanoclusters in the gas phase. |
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| Energetic Fuel Droplet Gasification with Liquid-Phase Reaction |
15 MAY 1998 |
31 pages |
| Authors:
William A. Sirignano; David N. Schiller; CALIFORNIA UNIV IRVINE DEPT OF MECHANICAL AND AEROSPACE ENGINEERING
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| An analytical and computational study of the gasification and oxidation of an energetic liquid fuel droplet is presented. Single-step, finite- rate. Arrhenius reaction rate expressions are used for exothermic liquid-phase decomposition and gas-phase oxidation. The liquid fuel is assumed to decompose to a gaseous product at a fixed number of bubble sites per unit mass (specified a priori) within the droplet. Decomposed gas escapes the droplet surface by: (1) decomposition ... |
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| Vapour Phase Growth of Thick Monocrystalline GaN Epitaxial Layers by Sandwich-Method |
OCT 97 |
60 pages |
| Authors:
E. N. Mokhov; Yu. A. Vodakov; A. D. Roenkov; P. G. Baranov; M. E. Boiko; JOINT STOCK CO AGENCY FOR SCIENCE AND TECHNOLOGY SAINT PETERSBURG (RUSSIA)
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| The basic investigations leading to the fabrication of thick (more than 0.2 mm) monocrystalline layers of GaN on the silicon carbide substrates are performed. GaN layers were grown by sublimation sandwich-method in ammonia atmosphere. GaN polycrystalline powder and metallic Ga were used as a vapor source. The growth was carried out in quartz reactors both horizontal, and vertical types, in furnaces with high-frequency heating. The possibility of growing of thick ... |
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| National Environmental Technology Test Sites (NETTS). Technology Demonstration Application Analysis Report. Titanium Dioxide Photocatalytic Oxidation of Vapors Contaminated with Chlorinated Compounds. Revision No. 1 |
12 SEP 1997 |
|
| Authors:
URS GREINER INC SACRAMENTO CA
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| Gas Phase Reactions for the CVD of Diamond Films |
01 OCT 96 |
8 pages |
| Authors:
J. E. Lawler; L. W. Anderson; WISCONSIN UNIV-MADISON DEPT OF PHYSICS
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| The study of the gas phase chemical and physical reactions that occur in the chemical vapor deposition (CVD) of diamond was the goal of ARO grants DAAH04-93-G-0260 and DAAH04-93-0185. We have developed an ultra-sensitive white light absorption spectroscopy technique and have used it together with absorption spectroscopy at the SRC synchrotron to determine the density of CH4, CH3, CH2, CH, C, and C2H2 and the dissociation fraction (H)/(H2)in various CVD ... |
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| In-Situ Monitoring and Feedback Control of Metalorganic Precursor Delivery. |
06 OCT 1995 |
23 pages |
| Authors:
William J. DeSisto; Brian Rappoli; DEPARTMENT OF THE NAVY WASHINGTON DC
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| The in-situ monitoring of metalorganic precursor delivery in a metalorganic chemical vapor deposition oxide system in high temperature super conductors (HTSC) film growth is accomplished by utilizing the distinct absorbance bands for metalorganic compounds. As an ultraviolet-visible light beam is passed through an effluent metalorganic gas stream the relative change in ultraviolet-visible absorbance of the ultraviolet-visible light beam passing through the effluent metalorganic gas stream is monitored. Stoichiometry control is ... |
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| Metal-Organic Vapor Phase Epitaxy of Controlled Deep Level Structures |
23 AUG 95 |
10 pages |
| Authors:
Thomas F. Kuech; Kevin L. Bray; WISCONSIN UNIV-MADISON DEPT OF CHEMICAL ENGINEERING
|
| The controlled introduction of oxygen into GaAs and In(x)Ga(1-x)As during metal organic vapor phase epitaxy was studied through the development of unique oxygen doping sources. The electrical, optical and other deep level properties of the GaAs: defect were studied over an oxygen concentration range of 10(exp 16) to 10(exp 20)/cu cm. Oxygen introduces several levels into the band gap of GaAs leading to the compensation of the electrically active shallow ... |
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| Use of D2 to Elucidate OMVPE Growth Mechanisms |
01 MAY 94 |
10 pages |
| Authors:
Gerald B. Stringfellow; UTAH UNIV SALT LAKE CITY
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| The research concentrated on two important areas of organometallic vapor phase epitaxial growth: (1) A study of the pyrolysis reactions and rates for five new antimony precursors: trivinylantimony (TVSb), triisopropylantimony (TIPSb), triallylantimony (TASb), tertiary- butyldimethyl-antimony (TBDMSb), and diisopropylantimonyhydride (DIPSbH). They have been compared with the standard precursor, trimethylantimony (TMSb). The pyrolysis temperatures for TIPSb, TASb, TBDMSb, and DIPSbH are all much lower than for TVSb, which is similar to TMSb. ... |
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| Evaluation of the OSHA 42 and NIOSH 5521 Methods in Determining the Free Isocyanate Concentration in Aerosols and Vapor Phases During Application of Two Component 1, 6 - Hexamethylene Diisocyanate Paints |
MAY 94 |
64 pages |
| Authors:
John L. Bell Jr; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH
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| When sampling for isocyanates, the two currently recommended methods (OSHA 42 and NIOSH 5521) have limitations that cause under estimation of the isocyanate concentration reported. During spray painting operations, isocyanate is present in both aerosol and vapor forms. When the NIOSH method is used the midget impinger inlet and outlet nozzles tend to plug as paint particles collect there during sampling. As the outlet nozzle opening becomes smaller, the velocity ... |
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| Interactions Between Organized, Surface-Confined Monolayers and Vapor- Phase Probe Molecules. 7. Comparison of Self-Assemblying Organomercaptan Monolayers Deposited on Gold from Liquid and Vapor Phases |
23 NOV 93 |
11 pages |
| Authors:
O. Chailapakul; L. Sun; C. Xu; R. M. Crooks; NEW MEXICO UNIV ALBUQUERQUE DEPT OF CHEMISTRY
|
| We report a comparative study of the structure and chemistry of methyl-terminated n-alkanethiol self-assembling monolayers (SAMs) formed from liquid and vapor phases. Three different SAMs are considered: Au/HS(CH2)nCH3, n=5, 11, and 15. Liquid-phase-deposited films were prepared by exposure of Au substrates to dilute ethanol solutions of the n-alkanethiols followed by ethanol rinsing, and vapor-phase-deposited SAMs were prepared by exposure of the Au surface to 10%-of-saturation n-alkanethiol vapors followed by N2 ... |
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| Progress Report for ONR Grant N00014-93-1-0015 (University of Wisconsin) |
15 JUL 93 |
4 pages |
| Authors:
WISCONSIN UNIV-MADISON CENTER FOR MATHEMATICAL SCIENCES
|
| The research effort of Slemrod has been directed to developing a discrete velocity kinetic theory model for liquid-vapor phase transitions. The aim of the research is to develop a 'basic principles' description of liquid- vapor phase transitions (such as those occurring in an internal combustion engine) which is not a priori biased by ad hoc equations of state (constitutive relations). The modelling is almost completely finished, numerical simulations are being ... |
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| Size Dependence of Chemical Reactivity of Gaseous Metal Clusters, A New Mechanistic Probe |
17 MAY 93 |
17 pages |
| Authors:
M. A. El-Sayed; CALIFORNIA UNIV LOS ANGELES DEPT OF CHEMISTRY AND BIOCHEMISTRY
|
| The determination of the mechanisms of chemical reactions leading to the formation of different types of materials is one of the principal occupations of many chemists today. To accomplish this, the dependence of the observed transformation is studied as a function of a number of intensive variables such as temperature, pressure, concentration of reactants as well as the Hydrogen ion concentration of the solution. In this account, we summarize recent ... |
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| Comparison of Epitaxial Growth Techniques for III-V Layer Structures |
22 MAY 92 |
|
| Authors:
G. B. Stringfellow; UTAH UNIV SALT LAKE CITY DEPT OF MATERIALS SCIENCE AND ENGINEERING
|
 | Epitaxial processes are essential for the growth of III/V alloy semiconductors for electronic and photonic devices. For the growth of elaborately structured materials such as heterojunctions, quantum wells, and superlattices for the fabrication of the most advanced electronic and photonic devices, in particular, vapor phase growth processes have become standard. This paper will deal specifically with the epitaxial (mainly vapor phase) growth of III/V semiconductor materials. The approach taken here ... |
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| In-Place Electrically Heated Regeneration of Vapor-Phase Activated Carbon |
SEP 90 |
90 pages |
| Authors:
Rhonda Levy; R. E. Hicks; Harris Gold; FOSTER-MILLER INC WALTHAM MA
|
| The Air Force is using the air stripping process to remove a variety of volatile organic contaminants from groundwater. Vapor-phase granular activated carbon (GAC) has proven successful in treating the contaminated air stream emanating from air stripping columns. but conventional regeneration methods are expensive, require transfer of the carbon. and degrade the carbon. The objective of this experimental program was to determine the feasibility of using electrically-heated processes for the ... |
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| Dynamics of Electronically Excited Species in Gaseous and Condensed Phase |
DEC 89 |
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| Authors:
P. K. Swaminathan; M. J. Redmon; C. S. Murthy; B. C. Garrett; G. A. Natanson; CHEMICAL DYNAMICS CORP UPPER MARLBORO MD
|
| In order to assess the potential of energetic molecules to be advanced rocket propellants, the Air Force High Energy Density Materials Program requires theoretical methods to predict the lifetimes of energetic molecules in condensed phase. This research met this need by developing novel dynamical methods which can be used to elucidate the microscopic dynamics controlling lifetimes relevant to energy storage in isolated and matrix-embedded molecules. This has resulted in the ... |
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| Ultra High Speed Compound Semiconductors and Real Time Signal Processing |
01 MAY 89 |
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| Authors:
J. P. Krusius; CORNELL UNIV ITHACA NY SCHOOL OF ELECTRICAL ENGINEERING
|
| This report is the annual report on research conducted under the auspices of the Joint Services Electronics Program at Cornell University. The research is grouped under two themes: (a) ultra high speed compound semiconductors, and (b) real time signal processing. Results on OMVPE materials growth, femtosecond laser probing of hot carriers, and ensemble Monte Carlo simulations are reported on under the first theme. Accomplishments on VLSI algorithms, fault tolerant architectures, ... |
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| Spectrometric Studies of Gas Phase Collision Processes |
10 FEB 89 |
|
| Authors:
J. B. Fenn; YALE UNIV NEW HAVEN CONN
|
| Measurements have been made of the total radiation intensity from free jets of carbon dioxide and carbon that were excited in the source by a corona discharge. The radiation per molecule, obtained from the ratio of total intensity to source density, increases sharply when source temperature and pressure are such as the produce clustering in a jet of unexcited gas. We believe this enhancement may be due to interaction between ... |
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| Laser Studies of Gas Phase Radical Reactions |
JAN 89 |
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| Authors:
G. Hancock; OXFORD UNIV (ENGLAND) PHYSICAL CHEMISTRY LAB
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| A series of measurements on free radicals produced by chemical reaction and photodissociation has been made, using laser methods for formation and in some cases, detection. Highly exothermic reactions between oxygen atoms and both CF2 and CHF radicals have been studied by time resolved Fourier transform infrared emission spectroscopy, yielding information on the reaction pathway, emitting products, kinetics of formation and quenching, and the nascent vibrational distributions. Emitting species hydrogen ... |
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| Ion Pair Solvation |
21 SEP 88 |
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| Authors:
Jack Simons; UTAH UNIV SALT LAKE CITY DEPT OF CHEMISTRY
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| New tools for the computational simulation of ion and ion pair dynamics in the gas phase and in solution have been developed. Both classical and quantum mechanical methods were explored. Monte Carlo techniques for incorporating thermodynamic equilibrium effects of surrounding solvent molecules have been incorporated into the computer codes. New techniques for computing highly accurate weak interaction energies among anions and solvent molecules have been development and tested. Keywords: Solvation; ... |
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| Electronic States of the XenHc1 Systems in Gas and Condensed Phases |
MAY 88 |
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| Authors:
Isidore Last; Thomas F. George; STATE UNIV OF NEW YORK AT BUFFALO DEPT OF CHEMISTRY
|
| Systems formed by one Cl, one H and one or several Xe atoms are considered by the semiempirical diatomics-in-ionic-systems method, which takes into account the charge delocalization in ionic states and the coupling between the neutral and ionic states. Calculations are performed both for gas-phase systems, such as van der Waals complexes and clusters XenHCl (n = 1,2,4,8,12) and ionic molecules (HXen)Cl, and for systems formed in Xe solids doped ... |
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| Laser Studies of Gas Phase Radical Reactions |
31 MAR 88 |
|
| Authors:
G. Hancock; OXFORD UNIV (ENGLAND) PHYSICAL CHEMISTRY LAB
|
| (1) CF Chemistry: Radiative lifetimes of the carbon fluoride ion has been measured, with values of 26.7 and 26.Ins obtained respectively. This is the first time that such direct measurements have been reported, and the work is now being prepared for submission to Chemical Physics Letters. (2) O + CF and O + CF2 reactions: Interferograms of IR emission accompanying the O + CF2 reaction have been recorded as a ... |
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| Gas Phase Ion-Molecule Chemistry of Phosphorus and Sulfur Compounds |
18 MAR 88 |
|
| Authors:
Charles H. DePuy; Veronica M. Bierbaum; COLORADO UNIV AT BOULDER DEPT OF CHEMISTRY
|
| This final report summarizes three years of research on the ion molecule chemistry of phosphorus and sulfur compounds in the gas phase. A new instrument, the tandem flowing afterglow SIFT drift, has been successfully designed and constructed; the instrument has exceptional sensitivity, resolution and versatility. New techniques have been developed for the preparation of reactive phosphorus and sulfur species. The gas phase chemistry of energy-rich ions and neutrals has been ... |
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| Shock Induced Chemistry: Application and Development of Ultrafast Nonlinear Probes of the Energy Dynamics of Molecules in Solids |
88 |
|
| Authors:
Michael D. Fayer; STANFORD UNIV CA DEPT OF CHEMISTRY
|
| We have made significant progress in a number of areas which have led to increased understanding of the dynamics of molecules in solids and in the development of new experimental techniques and associated theory for the investigation of solids and gas phase systems. This work will be briefly summarized in this section. A list of publications which have resulted from the research supported by this contract is given following the ... |
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| Gas-Phase Photoelectron Spectroscopy of Metals and Metal Oxides of Importance in the Upper Atmosphere |
01 OCT 87 |
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| Authors:
J. M. Dyke; SOUTHAMPTON UNIV (ENGLAND) DEPT OF CHEMISTRY
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| Photoelectron spectroscopy is used to study in the gas phase the electronic structure of metals and metal oxides which are of importance in the upper atmosphere. Ionization energies and cross-sections at discrete wavelengths are obtained. Exothermicities of charge exchange reactions of metal oxides and dioxides of importance to atmospheric modelling calculations will be determined. |
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| Investigation of Real-Time Two-Dimensional Visualization of Fuel Spray Liquid/Vapor Distribution via Exciplex Fluorescence |
30 AUG 87 |
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| Authors:
James F. Verdieck; Arthur A. Rotunno; Lynn A. Melton; UNITED TECHNOLOGIES RESEARCH CENTER EAST HARTFORD CT
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| This final report describes the achievements of the research program carried out under the subject contract. The overall aim of the study was to develop a new and unique combustion diagnostic technique which would provide the real-time, two-dimensional visualization of both the liquid and vapor phase of a fuel spray by means of laser-induced exciplex fluorescence. Significant achievements toward this end were: (1) Demonstration and application of an exciplex thermometer, ... |
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| The Kinetics and Dynamics of Iodine Monofluoride Formation in Gas-Phase Collisions |
17 JUN 87 |
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| Authors:
J. C. Whitehead; VICTORIA UNIV OF MANCHESTER (ENGLAND) DEPT OF CHEMISTRY
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| Chemiluminescence has been studied for the reactions of fluorine atoms with a range of inorganic iodides. From the form of the resulting IF(B) vibrational state distributions, it is concluded that in all F/iodide systems IF(B) is produced by the recombination of a fluorine atom with an excited iodine atom. This is supported by the results of VUV laser-fluorescence probing and kinetic modelling. Keywords: Chemiluminescence, Iodine monofluoride, Iodine atoms, Fluorine atoms, ... |
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| Chemical Reactions in Turbulent Mixing Flows |
01 JUN 87 |
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| Authors:
P. E. Dimotakis; J. E. Broadwell; A. Leonard; CALIFORNIA INST OF TECH PASADENA GRADUATE AERONAUTICAL LABS
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| Work continues primarily in gas phase turbulent mixing amd chemical reactions with extensions to compressible (supersonic) shear layers. In the gas phase shear layer work, investigations concentrate on subsonic shear layer free stream density ratio effects, and a design effort in support of the planned extension of the hydrogen-fluorine shear flow facility to supersonic flows. In jet flows, measurements of gas phase jet mixing, using laser Rayleigh scattering techniques developed ... |
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