| Thermal Decomposition Mechanism of 1-ethyl-3-methylimidazolium Bromide Ionic Liquid (Preprint) |
14 Sep 2011 |
35 pages |
| Authors:
Steven D Chambreau; Jerry A Boatz; Ghanshyam L Vaghjiani; Christine Koh; Oleg Kostko; Amir Golan; Daniel Strasser; Stephen R Leone; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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 | In order to better understand the volatilization process for ionic liquids, the vapor evolved from heating the ionic liquid 1-ethyl-3-methylimidazolium bromide was analyzed via tunable vacuum ultraviolet photoionization time of flight mass spectrometry (VUV-PI-TOFMS) and thermal gravimetric analysis mass spectrometry (TGA-MS). For this ionic liquid, the experimental results preclude the possible vaporization of intact ion-pairs or the formation of carbenes, but instead indicate the evolution of alkyl bromides and alkylimidazoles, ... |
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| Incompletely-Condensed Fluoroalkyl Silsesquioxanes and Derivatives: Precursors for Low Surface Energy Materials (Preprint) |
13 Sep 2011 |
17 pages |
| Authors:
Sean M Ramirez; Raymond Campos; Timothy S Haddard; Yvonne J Diaz; Rebecca L Stone; Joseph M Mabry; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| A novel synthetic method was developed for the controlled functionalization of Fluorinated Polyhedral Oligomeric SilSesquioxanes (F-POSS), which are useful as low surface energy materials for superhydrophobic and oleophobic materials. Utilizing triflic acid, open-cage compounds were created and then reacted with a variety of dichlorosilanes to produce functional F-POSS structures possessing alkyl, aryl, and acrylate based moieties. The crystal structure for an endo,endo disilanol F-POSS compound was determined by single crystal ... |
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| Inverse Coarse-Graining: A New Tool for Molecular Design |
16 Dec 2010 |
4 pages |
| Authors:
Gregory A Voth; UTAH UNIV SALT LAKE CITY
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| In this AFOSR project a very important set of atomistic and coarse-grained (CG) molecular dynamics (MD) simulations were designed and performed to study the structure and dynamical properties of room temperature ionic liquids (ILs). Eight papers in total were published during the grant period.1-8 Overall, a number of particularly high impact and ground-breaking publications have come out of this body of research, including a reviews in a Special Issue of ... |
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| Destruction Chemistry of Mustard Simulants |
04-Jul-2008 |
37 pages |
| Authors:
J W Bozzelli; F C Gouldin; E M Fisher; CORNELL UNIV ITHACA NY OFFICE OF SPONSORED PROGRAMS
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| This study investigates the destruction chemistry of organosulfur compounds under both pyrolytic and oxidative conditions. We focus on the destruction of alkyl sulfides that are surrogates for chemical warfare agents H, HD, and HT. We report our work on developing thermochemistry, reaction pathways and kinetic parameters for multiple chemical subsystems, using computational chemistry methods. We also report our experimental results from flow reactor experiments for pyrolysis and oxidation of two ... |
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| Platinum Complexes with Optical Limiting and Related Non-linear Optical and Electronic Properties |
NOV 2007 |
6 pages |
| Authors:
Michael Bruce; ADELAIDE UNIV (AUSTRALIA) DEPT OF CHEMISTRY
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| This project consisted of applying several synthetic approaches, some derived from model studies of molecular wires, to the production of several novel types of platinum-alkynyl complexes. |
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| High Mobility Conjugated Polymers |
20 OCT 2007 |
22 pages |
| Authors:
Samson A. Jenekhe; WASHINGTON UNIV SEATTLE DEPT OF CHEMICAL ENGINEERING
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| The performance of all current polymer electronic devices, such as organic field-effect transistors (OFETs), photovoltaic cells, and photodetectors, is limited primarily by the low charge carrier mobilities of current materials. To address this problem this project investigated various polymer semiconductors exhibiting high carrier mobilities and explored their device applications in electronics, optoelectronics, and nanoelectronics. Field-effect electron mobilities as high as 0.1 sq cm/Vs in a spin coated thin films of ... |
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| Alkanethiols on Platinum: Multicomponent Self-Assembled Monolayers |
2006 |
11 pages |
| Authors:
Dmitri Y. Petrovykh; Hiromi Kimura-Suda; Aric Opdahl; Lee J. Richter; Michael J. Tarlov; Lloyd J. Whitman; MARYLAND UNIV COLLEGE PARK DEPT OF PHYSICS
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| We have studied the formation of self-assembled monolayers (SAMs) of n-alkanethiols on platinum thin films using X-ray photoelectron spectroscopy (XPS), reflection-absorption infrared spectroscopy (RAIRS), spectroscopic ellipsometry (SE), and contact angle (CA) measurements. Specifically, SAMs of 1-hexanethiol, 1-dodecanethiol, and 1-octadecanethiol were grown on polycrystalline Pt films, and the effects of Pt surface preparation, deposition conditions, and solvent treatments on the initial quality and stability of the monolayer in air were investigated. ... |
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| Electrochemical Oxidation of Alkylnitro Compounds PP-1345 |
17 AUG 2004 |
31 pages |
| Authors:
Scott K. Lusk; ATK THIOKOL PROPULSION CORP BRIGHAM CITY UT
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| Energetic materials such as bis-dinitropropyl acetal-formal (BDNPA/F), 2,2',4,4',6,6'- hexanitrostillbene (HNS), 2,3-dimethyl-2,3-dinitrobutane (DMDNB), 1,3,5-triamino- 2,4,6-trinitrobenzene (TATB), and 1,3,3-trinitroazetidine (TNAZ) are of strategic interest to the Department of Defense (DoD). These compounds all share energetic structural elements consisting of nitro groups bound to carbon atoms, and the production of such materials is generally accomplished with numerous powerful chemical oxidizers. Use of these reagents generate pernicious waste streams, and these chemical oxidizers are ... |
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| Synthesis, Characterization, and Structural Investigations of 1-amino-3- Substituted-1,2,3-Triazolium Salts, and a New Route to 1-substituted-1,2,3- triazoles |
JAN 2004 |
31 pages |
| Authors:
Gregory Kaplan; Greg Drake; Kerri Tollison; Leslie Hall; Tommy Hawkins; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
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| Quarternary salts based upon 3-alkyl substituted 1-amino-1,2,3- triazolium cations (alkyl = methyl, ethyl, n-propyl, 2-propenyl, and n-butyl) have been synthesized and characterized by vibrational spectra, multinuclear NMR, elemental analysis, and DSC studies. Subsequent diazotization of these salts results in the exclusive formation of 1-alkyl-1,2,3-triazoles. Single crystal x-ray studies were carried out for 1-amino-3- methyl-1,2,3-triazolium iodide, 1-amino-3-ethyl-1,2,3-triazolium bromide, 1-amino-3-npropyl- 1,2,3- triazolium bromide, and 1-amino-3-n-butyl-1,2,3-triazolium bromide as well as the starting heterocycle, ... |
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| 1-Alkyl-4-Amino-1.2.4-Triazolium Salts, New Families of Ionic Liquids |
01 DEC 2003 |
28 pages |
| Authors:
Greg W. Drake; Tommy Hawkins; Kerri Tollison; Leslie Hall; Ashwani Vij; AIR FORCE RESEARCH LAB EDWARDS AFB CA MOTOR BRANCH
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| New classes of ionic liquids based upon the halide and nitrate salts of 1-alkyl substituted-4 amino-1,2,4-triazolium cations (n-alkyl =methyl -decyl, isopropyl, ally, and methylcylcopropyl) have been synthesized, characterized by vibrational spectra, multinuclear nmr, elemental analysis, and DSC studies. Single crystal x-ray diffraction studies were carried out on 1-isopropyl-4- amino-1,2,4-triazolium bromide, 1 -ethyl-4-amino- 1 ,2,4-triazolium bromide, 1 - n-propyl-4-amino- 1 ,2,4-triazolium bromide, 1-n- hexyl-4-amino-1 ,2,4- triazolium bromide, and 1-n-heptyl-4-amino-1,2,4-triazolium bromide, as ... |
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| Enzymatic Analysis of G- and V-Agents and Their Degradation Products |
01-Jul-2003 |
8 pages |
| Authors:
Ilya Elashvili; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD
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| We are presenting a rapid and highly reliable analytical methodology for nerve agents and their degradation products. The approach is to augment existing analytical methods with the specificity of the enzymatic degradation of the agents and their phosphonate ester products. The nerve agents can be hydrolyzed to their respective methylphosphonate alkyl ester (h-agent) products by alkali treatment or by specific hydrolytic enzymes, such as organophosphorus hydrolase (OPH) and organophosphorus acid ... |
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| Protection Against the Acute and Delayed Toxicities of Sulfur Mustard |
APR 2003 |
65 pages |
| Authors:
Zdenka Matijasevic; MASSACHUSETTS UNIV MEDICAL CENTER WORCESTER
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| Both the acute and delayed toxicities of DNA damaging agents represent the outcome of a race between protective and toxic pathways triggered by DNA damage. In order to identify targets for therapeutic intervention and conditions that can modulate the outcome of exposure to sulfur mustard we sought to investigate pathways and early events involved in cellular responses to SM- induced damage. We have identified two levels of cellular responses where ... |
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| Structural Effects on the Physical Properties of Ionic Liquids |
31 MAR 2003 |
3 pages |
| Authors:
Greg Drake; Tom Hawkins; John Wilkes; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
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| Recently work using ionic liquids has risen exponentially in both academic research efforts as well as by industrial large-scale organic synthesis. Much of these efforts have centered around the use of di-alkyl substituted imidazolium salts with an array of anions, many of which are commercially available. The pioneering work carried out by the USAF in the last several decades has shed some light upon some of the physical property effect ... |
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| A Study of the Thermal Stability, Degradation Mechanisms and Properties of Polymer/Organically Modified Layered Silicate Nanocomposites |
MAR 2003 |
97 pages |
| Authors:
Wei-Ping Pan; John T. Riley; Charles W. Lee; WESTERN KENTUCKY UNIV BOWLING GREEN DEPT OF CHEMISTRY
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| PS-MMT nanocomposites were prepared via suspension free radical polymerization of styrene in the dispersed organo-MMT. The results of XRD and TEM indicated that exfoliated nanocomposites were achieved. The effect of surfactants on the properties of then synthesized nanocomposites was studied. It is found that PS_MMT nanocomposite with 5% wt% of organo-MMT gave the greatest improvement in the thermal stability, and PS-MMT nanocomposites with 7.5% of organo- MMT showed the greatest ... |
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| Organic Polymers Modified with Inorganic Polyhedra |
28 FEB 2003 |
28 pages |
| Authors:
Timothy S. Haddad; Rene Gonzalez; ENGINEERING RESEARCH AND CONSULTING INC(ERC INC) EDWARDS AFB CA
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| Nano-sized inorganic clusters(POSS) can be successfully incorporated into a wide variety of different organic polymers. These POSS clusters cause increases to the thermal transitions and mechanical properties of the polymers they are copolymerized into. Not every POSS is the same and the POSS effect on the properties of analogous polymers shows a dependency on the type of alkyl group on the POSS cluster. Rheology of high molecular weight PDMS grafted ... |
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| POSS Polystyrene Copolymers Reactivity and Control |
28 FEB 2003 |
25 pages |
| Authors:
Brian Moore; Timothy Haddad; Rene Gonzalez; ENGINEERING RESEARCH AND CONSULTING INC(ERC INC) EDWARDS AFB CA
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| Nano-sized inorganic clusters(POSS) can be incorporated into polystyrene copolymers from 1-99 wt%. These POSS clusters cause increases to the thermal transitions and mechanical properties of the polymers they are copolymerized into. The POSS effect on the properties of analogous polymers shows a dependency on the type of alkyl group on the POSS cluster. A degree of control over molecular weight can be made using standard kinetic polystyrene parameters. High molecular ... |
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| Tritylsulfinylamine: A New Member in the Family of Sulfinylamines |
25 SEP 2002 |
23 pages |
| Authors:
Karl O. Christe; Michael Gerken; Ralf Haiges; Stefan Schneider; Thorsten Schroer; UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF CHEMISTRY
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| Triphenylmethyl N-sulfinylamine (trityl-NSO) was prepared from the reaction of trityl amine and SOCl2. Trityl-NSO was characterized by 1H, 13C, and 14N NMR spectroscopy in CH2C12 solution and by Raman and infrared spectroscopy in the solid state. Crystals of trityl NSO were grown from n-heptane and characterized by single crystal X-ray diffraction (P1-bar, alpha = 8.9642(9) A, b = 9.2135(9) A, c = 11.0645(11) A, alpha = 93.578(2)0, Beta = 101.098(2)0, ... |
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| 26TH International Symposium on Free Radicals. Assisi, Italy, 2-7 September 2001. Book of Abstracts |
07 SEP 2001 |
227 pages |
| Authors:
PERUGIA UNIV (ITALY) DIPT DI CHIMICA
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| Sessions: (1) Reaction Dynamics: Experiment and Theory. Reactivity of the O(D1) atom: from state-to-state dynamics to multiple pathway chemistry; Quantum dynamics on some atom-hydrogen insertion reactions; UV and near-UV photodissociation dynamics of small hydrocarbon free radicals. (2) Spectroscopy. Some 'radical' new experiments in molecular spectroscopy; Linear triatomic radicals containing transitions metal atoms: a case history of vibronic coupling; Fourier-transform microwave spectroscopy of the acetyl radical. (3) Astrochemistry. Low temperature reactions ... |
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| Protection Against the Acute and Delayed Toxicities of Sulfur Mustard |
APR 2001 |
26 pages |
| Authors:
Zdenka Matijasevic; Michael Volkert; MASSACHUSETTS UNIV MEDICAL CENTER WORCESTER
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| Both the acute and delayed toxicities of DNA damaging agents like sulfur mustard (SM) appear to represent the outcome of a race between protective and toxic pathways triggered by DNA damage. Results obtained within the framework of our first objective to investigate the mechanisms involved in processing SM-induced DNA modifications, have revealed that both nucleotide excision repair (NER) and base excision repair (BER) are involved in processing SM-induced DNA damage. ... |
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| AASERT: Microphase Separation, Viscoelastic Properties and Aging of Amorphous Polyurethane Elastomers |
15 MAR 2001 |
12 pages |
| Authors:
Stuart L. Cooper; Sachin Velankar; DELAWARE UNIV NEWARK DEPT OF CHEMICAL ENGINEERING
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| Thermally stable polynrethanes with low flow temperatures were synthesized at fixed soft segment content (50%), and the relationship between their microstructure and linear viscoelastic properties were studied as a function of block length and block incompatibility. It was found that the materials changed from homogeneous to microphase-separated as segment length and incompatibility increased. Dynamic mechanical experiments demonstrated that unlike most di-and triblock copolymers, polyurethanes are incapable of developing long-range order ... |
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| Ignition of Isomers of Pentane: An Experimental and Kinetic Modeling Study |
04 AUG 2000 |
9 pages |
| Authors:
M. Ribaucour; R. Minetti; L. R. Sochet; H. J. Curran; W. J. Pitz; C. K. Westbrook; UNIVERSITE DES SCIENCES ET TECHNOLOGIE LILLE (FRANCE)
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| Experiments in a rapid compression machine were used to examine the influences of variations in fuel molecular structure on the autoignition of isomers of pentane. Autoignition of stoichiometric mixtures of the three isomers of pentane were studied at compressed gas initial temperatures between 640 K and 900 K and at precompression pressures of 300 and 400 torr. Numerical simulations of the same experiments were carried out using a detailed chemical ... |
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| Towards the Molecular Design of Novel Sensor and High Tech Polymeric Systems |
20 APR 2000 |
8 pages |
| Authors:
Karl F. Freed; Jacek Dudowicz; CHICAGO UNIV IL JAMES FRANCK INST
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| We have greatly extended and applied our theory to describe the thermodynamic properties of mixtures polymers (polymer blends), with applications to explaining experimental data that cannot be explained by any other theories. The extensions involve elucidating general trends in the pressure dependence of polymer phase diagrams, the development of a new theory for random copolymer systems with explicit evaluation of the entropic contributions ... |
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| Mechanistic Investigations of Zero-Valent Metal Reactions with Organohalides |
10 NOV 1999 |
359 pages |
| Authors:
A. L. Roberts; W. A. Arnold; U. Jans; L. A. Totten; J. P. Fennelly; JOHNS HOPKINS UNIV BALTIMORE MD DEPT OF GEOGRAPHY AND ENVIRONMENTAL ENGINEERING
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| Mechanisms of organohalide reactions with zero-valent metals in aqueous solution were examined in batch reactors. Of particular interest were questions of concertedness of electron transfer; reaction kinetics and pathways (especially the extent to which reductive alpha and beta elimination competed with stepwise hydrogenolysis); and correlations between reactivity and reduction potentials. Results with probe compounds (vicinal dibromide stereoisomers and alkyl monobromide free radical "docks") suggested that ... |
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| Mechanisms for Breast Cancer Cell Resistance to Doxorubicin and Solutions to Resistance and Side Effects (97 Breast) |
OCT 1999 |
21 pages |
| Authors:
Tad Koch; COLORADO UNIV AT BOULDER
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| Recent studies indicate that doxorubicin alkylates DNA through catalytic production of formaldehyde and utilization of formaldehyde for attaching itself to 0-bases. This discovery prompted the synthesis of anthracycline-formaldehyde conjugates as improved anti-tumor dmgs. The first conjugate, Doxoform, was equally toxic to both sensitive and resistant breast cancer cells but is predicted to be hydrolytically too unstable. The second conjugate, Epidoxoform, from reaction of epidoxorubicin with formaldehyde was synthesized and characterized ... |
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| Use of the Comet Assay to Detect DNA Damage in Sulfur Mustard-Exposed Human Peripheral Blood Lymphocytes |
JUL 1999 |
27 pages |
| Authors:
Janet Moser; Claire F. Levine; Delvena R. Thomas-Dunmey; Anthony J. Callan; William J. Smith; ARMY MEDICAL RESEARCH INST OF CHEMICAL DEFENSE ABERDEEN PROVING GROUND MD
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| Sulfur mustard (HD) is a vesicating agent that alkylates cellular DNA and produces DNA strand breaks. The comet assay (single-cell gel electrophoresis) was used to detect HD-induced DNA single strand breaks in human peripheral blood lymphocytes (PBL). Specific steps taken to perform the comet assay in our laboratory are outlined. Briefly, PBL were mixed with agarose, mounted on a microscope slide, and lysed. The cellular DNA was treated with an ... |
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| Nonlinear Optical Films From Pair-Wise-Deposited Semi-Ionomeric Syndioregic Polymers |
16 MAR 1999 |
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| Authors:
Richard A. Hollins; Geoffrey A. Lindsay; Marion J. Roberts; Peter Zarras; John D. Stenger-Smith; DEPARTMENT OF THE NAVY WASHINGTON DC
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 | This invention is comprised of new nonlinear optic polymers and a new Langmuir-Blodgett (LB) film deposition scheme for which these polymers were designed. The invention is unique because it produces an electro-optic film which has never undergone electric-field poling nor high temperature treatment. It eliminates the dilution effect of the long hydrophobic alkyl groups, and creates stronger ionic bonds between the polymer chains. Finally, the invention reduces the time to ... |
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| Thermoset Polymers from Inorganic Arylacetylenic Monomers |
15 SEP 1998 |
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| Authors:
Daniel Bucca; Teddy M. Keller; DEPARTMENT OF THE NAVY WASHINGTON DC
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| The present invention is a thermoset having the repeating unit: R'- (Ae' -Ar'-M- Ar"-Ae")-R" where R' and R" are independently selected from the group consisting of hydrogen, unsubstituted alkyl groups, substituted alkyl groups, unsubstituted aryl groups, and substituted aryl eroups, where Ae' and Ae" are independently selected groups with one or more unsaturated carbon-carbon bond and at least two crosslinking moieties, where Ar' and Ar" are independently selected substituted or ... |
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| Rydberg States of Energetic Materials |
01 JUL 1998 |
4 pages |
| Authors:
Elliot R. Bernstein; COLORADO STATE UNIV FORT COLLINS DEPT OF CHEMISTRY
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| Energetic materials are modeled experimentally and theoretically with regard to possible excited electronic Rydberg state reactivity and dissociation. The systems of methyl and ethyl alkyl amines have been studied. We show that these Rydberg states can be both highly reactive and dissociative. Thus, excited Rydberg states are a possible route to radicals and other reactive species for these model systems. We are presently expanding our experimental capabilities to allow study ... |
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| Molecular Structure and Ordering of Phospholipids at a Liquid-Liquid Interface |
JUN 1998 |
19 pages |
| Authors:
R. A. Walker; J. C. Conboy; G. L. Richmond; OREGON UNIV EUGENE DEPT OF CHEMISTRY
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| Vibrational sum frequency spectroscopy in conjunction with interfacial pressure measurements provide direct information about the molecular structure of phosphocholine monolayers adsorbed to the interface between D2O and carbon tetrachloride. Monolayers form from breakup at the interface of aqueous phase phosphocholine vesicles. For the saturated, symmetric, dialkyl phosphocholines used in this study, alkyl chain conformation as inferred from the relative intensity of CH stretch vibrational bands depends on both alkyl chain ... |
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| Mechanistic Studies of C-H Activation Catalysts for Direct Organic Fuel Cell Applications |
25 MAR 1998 |
6 pages |
| Authors:
H. B. Gray; J. E. Bercaw; J. A. Labinger; J. Winkler; CALIFORNIA INST OF TECH PASADENA
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| The goal of this program is to obtain fundamental understanding that will lead to design of catalysts or catalyst systems for C-H bond activation that can function in direct organic fuel cells, and that are based upon molecular species, rather than metal surfaces. In studying C-H activation by platinum complexes, we have used the results of prior mechanistic studies to design complexes that effect C-H activation under milder conditions, and ... |
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| Super-Hydrides |
22 DEC 1997 |
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| Authors:
Herbert C. Brown; PURDUE UNIV LAFAYETTE IN DEPT OF CHEMISTRY
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| In accordance with the specific aims of the project our main focus has been on the asymmetric reduction of prochiral ketones. We further explored the capability of our reducing agent, B-chiorodiisopinocampheylborane (Ipc2BCl), for asymmetric reductions. We studied the kinetic resolution of alpha-tertiary monocyclic and bicyclic ketone and developed optimum conditions to obtain the product alcohol, or the ketone, or both, in very high yields. Ipc2BCl controls the stereochemical outcome in ... |
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| The Molecular Modelling of Silane Primers Adhesive Joints and Composite Materials |
DEC 97 |
30 pages |
| Authors:
P. M. Hobbs; A. J. Kinloch; IMPERIAL COLL OF SCIENCE AND TECHNOLOGYLONDON (UNITED KINGDOM) DEPT OF MECHANICAL ENGINEERING
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| The adhesion of a series of organosilanes, with varying lengths of alkyl chain, adsorbed on different metal-oxide substrates have been modelled using a computational molecular dynamics (MD) approach. The silanes modelled were: (a) the fully hydrolysed version of gamma- glycidoxypropyltrimethoxysilane (GPMS), (b) the fully hydrolysed version of gamma- glycidoxydecyltrimethoxysilane (GDMS), and (c) the fully hydrolysed version of gamma- glycidoxyeicosyltrimethoxysilane (GEMS). The substrates were corundum (alpha-Al2O3), an amorphous form of aluminium ... |
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| Molecule-Sized Gates Based on Surface-Confined Dendrimers |
31 JUL 97 |
13 pages |
| Authors:
Mingqi Zhao; Hideo Tokuhisa; Richard M. Crooks; TEXAS A AND M UNIV COLLEGE STATION DEPT OF CHEMISTRY
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| In this report we demonstrate for the first time that surface confined-dendrimers embedded within self-assembled monolayers (SAMs) of alkylthiols can act as ion gates of molecular dimension. These composite organic thin films are conceptually, structurally, and chemically very similar to the membrane/protein composites found in nature. The key findings of this paper are that dendrimers can be well sealed within self-assembled alkylthiol monolayers and that as a function of the ... |
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| Vibrational Spectroscopy of Molecules at Liquid/Liquid Interfaces |
30 MAY 97 |
27 pages |
| Authors:
G. L. Richmond; OREGON UNIV EUGENE DEPT OF CHEMISTRY
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| Measurement of the nonlinear vibrational spectrum of molecules at a liquid/liquid interface has recently been achieved by the use of total internal reflection sum frequency vibrational spectroscopy (TIR SFVS). This report describes this nonlinear optical technique and gives examples of the type of information which has been obtained about interfacial water and surfactants adsorbed at this interface. The surfactants examined include simple alkyl cationic and anionic surfactants commonly used in ... |
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| Ligand Exchange Reactions in Organometallic Vapor-Phase Epitaxy |
23 MAY 97 |
17 pages |
| Authors:
Menno J. Kappers; Michael L. Warddrip; Kerri J. Wilkerson; Robert F. Hicks; CALIFORNIA UNIV LOS ANGELES
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| The organometallic vapor phase epitaxy (OMVPE) of CdZnTe and InGaAs alloys has been studied using on-line infrared spectroscopy and ex-situ X-ray crystallography. During II-VI OMVPE, ligand exchange reactions between dimethylcadmium and diethylzinc produce more reactive ethylcadmium species, and less reactive methylzinc species. During III-V OMVPE, reactions between trimethylindium and triethylgallium produce more reactive ethylindium compounds and less reactive methylgallium compounds. The large difference in reactivities of these sources makes it ... |
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| Pretreatment with P-Nitrophenyl Phosphoramides: Spontaneous Reactivation of Blood ChE after Oral Administration to Guinea Pigs |
MAY 97 |
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| Authors:
M. Polhuijs; H. J. van der Wiel; J. P. Langenberg; H. P. Benschop; PRINS MAURITS LABORATORIUM TNO RIJSWIJK (NETHERLANDS)
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| Oral efficacy of p-nitrophenyl 2,2,2-trifluoroethyl phosphoramidate, 2,2-difluoroethyl p-nitrophenyl phosphoramidate, 2-fluoroethyl p-nitrophenyl phosphoramidate, n-butyl p-nitrophenyl phosphoramidate and of the reference compounds pyridostigmine and physostigmine has been studied in the guinea pig, as determined by measuring spontaneous reactivation of blood ChE inhibited by these pretreatment compounds. The fluoroalkyl phosphoramidates were not absorbed sufficiently from the gastro-intestinal tract into blood. Blood AChE was not inhibited by the 2-fluoro-compound at all and the time-course ... |
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| Detection of Hydroxysarin in Serum Samples of Japanese Citizens Allegedly Exposed to Sarin |
APR 97 |
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| Authors:
D. H. Platenburg; D. Noort; A. G. Hulst; A. L. De Jong; J. P. Langenberg; PRINS MAURITS LABORATORIUM TNO RIJSWIJK (NETHERLANDS)
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| The treatment of chemical warfare casualties of the Iran-Iraq War has clearly demonstrated the need for reliable and sensitive methods for retrospective detection of exposure to chemical warfare agents. Recently, a new type of proliferation of chemical warfare agents has emerged with the use of nerve agents by the AUM Shinriyko sect in terrorist attacks in the Tokyo subway and at Matsumoto, Japan. Our laboratory is engaged in the development ... |
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| Capillary Electrophoresis Coupled On-Line with Flame Photometric Detection: Determination of Alkylphosphonic Acids |
FEB 97 |
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| Authors:
Ch. E. Kientz; E. W. Hooijschuur; PRINS MAURITS LABORATORIUM TNO RIJSWIJK (NETHERLANDS)
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| The separation performance and sensitivity of an earlier developed system which uses capillary electrophoresis coupled on-line with a flame photometric detector (originally developed for gas chromatography) are considerably improved. The liquid junction used in order to decouple the electrical field shows a negligible influence on the performance of the system as compared with on-line UV detection. The system is used to determine alkylphosphonic acids, which are the hydrolysis products of ... |
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| Chemical Reactivity as a Function of Molecular Distance and Orientation: A Fundamental Study of Oxidative Coupling Polymerization |
09 JAN 97 |
17 pages |
| Authors:
R. S. Duran; FLORIDA UNIV GAINESVILLE DEPT OF CHEMISTRY
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| A series of surface-active, functionalized anilines were polymerized at fluid interfaces. By carefully maintaining isobaric conditions, kinetic and derived thermodynamic activation parameters were determined. The substitution position of the alkyl moiety on the aniline ring and the applied surface pressure was found to strongly influence the kinetics. Further analysis allowed a two rate constant model to be developed. The experiments were also extended to the polymerization of thin films at ... |
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| DeNovo Design of Protein-Protein Interactions |
SEP 96 |
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| Authors:
Wesley E. Stites; ARKANSAS UNIV FAYETTEVILLE DEPT OF CHEMISTRY AND BIOCHEMISTRY
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| Final results are reported in three areas: Chemical crosslinking of proteins, the effects of surface hydrophobicity, and the design of a dimeric protein. In the area of chemical crosslinking in collaboration with Dr. Clarence Broomfield at USAMRICD it was shown that mustard gas alkylates and crosslinks proteins at cysteine residues. It was also shown that crosslinked protein dimers differ dramatically from non-cross linked protein in their stability and denaturation behavior. ... |
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| Analysis of Nerve Agent Degradation Products Using Capillary Ion Electrophoresis |
AUG 96 |
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| Authors:
Paul C. Bossle; Michael W. Ellzy; Stuart A. Oehrle; EDGEWOOD RESEARCH DEVELOPMENT AND ENGINEERING CENTER ABERDEEN PROVING GROUND MD
|
| A method has been developed for the analysis of nerve agent degradation products using capillary ion electrophoresis. Analysis of the primary degradation products isopropyl methylphosphonic acid (IMPA), ethyl methylphosphonic acid (EMPA), pinacolyl methylphosphonic acid (PMPA), and methylphosphonic acid (MPA) was accomplished with run times of <5 min. Detection of low milligrams/liter levels of degradation products in spiked water samples was possible. The analysis of the alkyl methylphosphonic acids required little ... |
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| Polymeric Self-Assembled Monolayers. 4. Synthesis, Characterization, and Stability of omega-Functionalized, Self-Assembled Diacetylenic and Polydiacetylenic Monolayers |
24 JUN 96 |
69 pages |
| Authors:
T. Kim; K. C. Chan; R. M. Crooks; Q. Ye; L. Sun; TEXAS A AND M UNIV COLLEGE STATION DEPT OF CHEMISTRY
|
| Here we discuss the preparation and characterization of photopolymerizable, self-assembled monolayers (SAMs) that consist of acid-, hydroxyl-, and methyl-terminated n-alkylthiois containing a diacetylene group (HS(CH 2)10C equivalent C(triple bonds)CC(triples bonds)C(CH2)10X; X=COOH, CH2OH, and CH3, respectively). The acid and hydroxyl surfaces are readily amenable to further synthetic elaboration, while the methyl-terminated SAM results in a clean, low-energy surface. As demonstrated by Fourier transform infrared external reflectance spectroscopy (FTIR-ERS), surface-enhanced Raman spectroscopy ... |
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| Hydrolysis and Condensation of Tin(IV) Alkoxide Compounds: The Control of Structural Evolution |
JUN 96 |
7 pages |
| Authors:
M. J. Hampden-Smith; NEW MEXICO UNIV ALBUQUERQUE DEPT OF CHEMISTRY
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| We have studied ester elimination in a number of model systems to determine the criteria which promote or inhibit such reactions. The model systems generally involve metal centers which possess NMR active nuclei such as 29Si, 119, 117Sn and 207Pb. In these systems, we have conducted a number of 170 labeling experiments which reveal that ester elimination is probably an associative process that requires electropositive metal alkoxide centers, accessible coordination ... |
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| Synthesis of Novel Tetrametallic and Trimetallic Compounds from Reactions of MMe3(M=Al,Ga) with 1,2-(H2E)2C6H4(E=N,P) |
21 MAY 96 |
32 pages |
| Authors:
Richard L. Wells; Hamid Rahbarnoohi; Paul B. Glaser; Louise M. Liable-Sands; Arnold L. Rheingold; DUKE UNIV DURHAM NC DEPT OF CHEMISTRY
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| The independent 2:1 reactions of MMe3 (M = Al, Ga) with 1,2-(H2P) 2C6H4 resulted in the formation of the novel 8-membered tetrametallic ring compounds with the general formula ((Me2M)4((mu- PH)2(C6H4))2) (M = Al (1), Ga (2)) in a nearly quantitative yield. Combining AlMe3 and 1,2-(H2P)2C6H4 in a 1:1 ratio also afforded 1. The reaction of AlMe3 with 1,2-(H2N)2C6H4 (2:1) yielded the novel asymmetric compound ((Me2Al)2AlMe(C6H4(NH)2)2)-AlMe3 (3). Compound 3 is composed ... |
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| Enzymatic Polymerization of Phenolic Biomonomers Derived from Cashew Nut Shell Liquid (CNSL) |
07 MAY 96 |
22 pages |
| Authors:
K. S. Alva; P. L. Nayak; J. Kumar; S. K. Tripathy; MASSACHUSETTS UNIV LOWELL DEPT OF CHEMISTRY
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| Enzymatic polymerization of alkyl phenols derived from a renewable resource, viz. cashew nut shell, has been carried out in dioxane-water mixture. The reaction and reaction products have been characterized by a number of spectroscopic, microscopic and thermometric methods. These monomers have also been copolymerized with various substituted phenols. The homopolymers are soluble in organic solvents while the copolymers are crosslinked with negligible solubility. Enzymatic polymerization in dioxane-water solvent mixture results ... |
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| Miscibility, Solubility, and Viscosity Measurements for R-236EA with Potential Lubricants |
MAY 1996 |
63 pages |
| Authors:
S. C. Zoz; M. B. Pate; IOWA STATE UNIV AMES
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| The report gives results of miscibility, solubility, and viscosity measurements of refrigerant R-236ea with three potential lubricants. The lubricants were a mineral oil, alkylbenzene, and polyol ester, each with a nominal viscosity of 68 cSt. The miscibility tests were performed in a test facility consisting of a series of miniature test cells in a constant- temperature bath. The bath temperature was precisely controlled over a range of -50 to 90 ... |
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| Preparation and Characterization of Arsine Derivatives: X-Ray Crystal Structures of As(Si(t)BuMe2)3, As(SiMe3)2,(SiPh3), Et3Ga.As(SiMe3)2(SiPh3), and As(SePh)3 |
MAY 96 |
30 pages |
| Authors:
Ryan A. Baldwin; Hamid Rahbarnoohi; Leonidas J. Jones Iii.; Andrew T. McPhail; Richard L. Wells; DUKE UNIV DURHAM NC DEPT OF CHEMISTRY
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| For the last decade, our laboratory has had great interest in the chemistry of silylarsines 1. These compounds, in combination with Group 13 alkyl or halogen derivatives, have been shown to be excellent starting reagents for preparing compounds which contain the Group 13 element-arsenic bond. Although the reactivity of silylarsines is well documented (vide supra), structural characterization data for these species has been limited to solution- and gas- phase measurements ... |
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| Environmentally Benign Sol-Gel Surface Treatment for Aluminum Bonding Applications |
22 APR 1996 |
34 pages |
| Authors:
Joseph H. Osborne; Kay Y. Blohowiak; Donald F. Sekits; BOEING DEFENSE AND SPACE GROUP SEATTLE WA
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| A surface treatment process for aluminum using sol-gel chemistry has been developed that produces strong adhesive bonds without the rinse water requirements of traditional anodizing or etching processes. In this process, an acid catalyzed sol composed of zirconium alkoxide and a silane coupling agent in water was applied to etched or grit blasted aluminum substrates by immersion or spraying. After drying at 212 deg F for 1 hour, panels were ... |
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| Fluoroalkyl Iodide Photodecomposition on Diamond(100)-An Efficient Route to the Fluorination of Diamond Surfaces |
96 |
7 pages |
| Authors:
V. S. Smentkowski; J. T. Yates Jr; PITTSBURGH UNIV PA
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| The photodecomposition of CF3I and C4F9I overlayers at 119K on diamond (100) surfaces has been shown to be an efficient route to fluorination of the diamond surface. X-ray photoelectron spectroscopy (XPS) has been used for photoactivation as well as for studies of the following processes: the photodecomposition of the fluoroalkyl iodide molecules: the attachment of the photofragments to the diamond surface; and the thermal decomposition of the fluoroalkyl ligands. Chemisorbed ... |
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| Amphiphilic Linear-branched Copolymers and Their Fluorinated Dendritic Analogs |
1996 |
3 pages |
| Authors:
Dong Yu; Jean M. Frechet; CALIFORNIA UNIV BERKELEY DEPT OF CHEMISTRY
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| Copolymers of PEG and analogs of second generation dendrimer have been synthesized and characterized. Normal polyether dendrimers can be replaced by other branched structures with similar physical properties. Incorporation of fluorinated chains enhance the hydrophobicity of the dendrimer. Attachment of long alkyl chains to dendrimers to achieve the same goal is under investigation and applications of the amphiphilic copolymers are being explored. |
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Reports by Keyword(s)
ALKYL RADICALS
