| Iodine L-Edge X-Ray Absorption Fine Structure Studies of Polymer-Iodide Salt Complexes |
22 DEC 87 |
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| Authors:
M. L. DenBoer; S. G. Greenbaum; HUNTER COLL NEW YORK DEPT OF PHYSICS AND ASTRONOMY
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 | We report measurements of extended x-ray absorption fine structure (EXAFS) and x-ray absorption near edge structure (XANES) of the L edge of iodine in the polymer electrolytes PPO8NaI, PPO8LiL, and PEI10NaI. The EXAFS indicates a disordered environment for the iodine, although the PEI complex does exhibit several weak oscillations indicating a significantly less disordered environment of the anion in this complex. The XANES results suggest that the iodine is becoming ... |
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| Research on Stable Processible Conducting Polymers for Electronic Applications |
21 DEC 87 |
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| Authors:
Samson A. Jenekhe; Stephen T. Wellinghoff; HONEYWELL INC BLOOMINGTON MN PHYSICAL SCIENCES CENTER
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| The primary objective of this three-year research project was to develop environmentally stable and processible electronically conductive polymers for potential applications in electronics, electro optics, and sensors. Our general approach was to synthesize and characterize several new heteroaromatic polymers and tailor their electronic, optical, and traditional polymer properties for these applications. A further objective was to understand the structure/electronic property relationships in electronically conducting heteroaraomatic polymers. Many new electronically conducting ... |
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| Functional Consequences of Chemical Modification of the Saxitoxin Binding Site on Neuronal Sodium Channels |
15 DEC 87 |
17 pages |
| Authors:
Bruce K. Krueger; MARYLAND UNIV BALTIMORE SCHOOL OF MEDICINE
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 | Sodium channels from rat brain have been studied at the single channel level in planar phospholipid bilayer membranes in the presence of the activating neurotoxins, batrachotoxin (BTX) and veratridine (VER). Three problems have been investigated. First, an Eyring rate theory model has been developed to account for ion movement through the channel under a variety of experimental conditions assuming that permeant and blocking cations interact with the toxin binding site ... |
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| Ion Gun Generated Electromagnetic Interference on the Scatha Satellite |
DEC 87 |
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| Authors:
Leonard E. Weddle; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| Spacecraft charging at geosynchronous orbit can cause satellite anomalies and failure. Experiments in charge control were conducted on the joint Air Force/NASA P78-2 (SCATHA) satellite using both electron and positive ion emission systems. These experiments were monitored by a variety of plasma wave and particle detectors. Plasma wave data show that arcing was taking place during non-neutralized ion beam emission. The arcing was seen to cease when either the beam ... |
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| Quantum Chemical Investigations of the Mechanism of Cationic Polymerization and Theoretical Prediction of Crystal Densities and Decomposition Pathways of Energetic Molecules |
15 NOV 87 |
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| Authors:
Joyce J. Kaufman; JOHNS HOPKINS UNIV BALTIMORE MD
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| This paper discusses: Program Enhancements and New Program Developments on the CRAY Supercomputer; MRD-CI Calculations for Cationic Polymerization of Energetic Oxetanes; Ab-Initio MRD-CI Calculations for Breaking a Chemical Bond in a Molecule in a Crystal; or Other Solid Environment POLY- CRYST; This past year we have made a significant breakthrough. We developed and implemented and used successfully the strategy for ab-initio MRD- CI(multireference double excitation - configuration interaction) calculations for ... |
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| Role of Water in Proton-Hydroxide Conductance Across Model and Biological Membranes |
10 NOV 87 |
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| Authors:
David W. Deamer; CALIFORNIA UNIV DAVIS DEPT OF ZOOLOGY
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| The goal of this research is to understand the barrier properties of lipid bilayers, and particularly the role of transient defects in providing pathways for ion flux. Our approach is to compare proton and potassium flux, using membrane perturbants to probe the barrier. We have found that perturbants such as n-alkanols and diols cause increments in cation flux, which can be used to predict anesthetic effects. The increments are caused ... |
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| Effect of Electric Fields on Membrane Bound (Na,K)-ATPase |
06 NOV 87 |
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| Authors:
Tian Y. Tsong; JOHNS HOPKINS UNIV BALTIMORE MD DEPT OF BIOLOGICAL CHEMISTRY
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| A protein of a cell membrane is structurally sensitive to an electric field because of its charges, helix dipoles and polarizability. When such a protein is exposed to an applied oscillating electric field, the conformational oscillation of the protein can be coupled to driving an endergonic reaction. We have investigated how such an interaction between the sodium, potassium +(Na,K)- ATPase of human erythrocytes and an a.c. field leads to active ... |
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| Adsorption and Desorption of 2,4,6-Trinitrotoluene by Soils |
NOV 1987 |
36 pages |
| Authors:
Judith C. Pennington; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS ENVIRONMENTAL LAB
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| Soil samples collected from 12 Army Ammunition Plants were characterized by chemical and physical tests. Tests included pH, particle size distribution, cation exchange capacity, electrical conductivity, percent organic carbon, and extractable iron, manganese, aluminum, and calcium. Soils were found to be primarily silty loams, low in organic carbon. Trinitrotoluene (TNT) reached a steady state of adsorption with test soils (i.e., no change in TNT solution concentration) within 2 hr of ... |
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| Electron Production, Electron Attachment and Charge Recombination Process in High Pressure Gas Discharges |
NOV 87 |
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| Authors:
Long C. Lee; SAN DIEGO STATE UNIV CA DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
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| A mass spectrometer system has been purchased by this grant. The purchased equipment were used to construct an apparatus as shown in Fig. 1. This apparatus includes a quadrupole mass analyzer, ion detectors, high vacuum pump system, a vacuum chamber, electronics and power supplies, as well as optical multichannel analyzer and excimer laser. This apparatus is being used to analyze the positive and negative ions produced in electrical discharges. The ... |
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| Proceedings of the Topical Meeting on the Microphysics of Surfaces, Beams, and Adsorbates (2nd) Held in Sante Fe, New Mexico on 16-18 February 1987 |
31 OCT 87 |
163 pages |
| Authors:
Jarus W. Quinn; T. M. Mayer; D. J. Ehrlich; T. J. Chuang; OPTICAL SOCIETY OF AMERICA WASHINGTON D C
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| Partial Contents: The reaction of Si(100) 2 x 1 with NO and NH3: The role of surface dangling bonds; Molecular dynamics simulation of low-energy beam deposition of silicon; Visible laser etching of refractory metals by surface modification; Modulated molecular beam studies of the surface chemistry of silicon reaction with reactive gases; Effects of Ar(+) angle of incidence on the etching of Si with Cl2 and low energy Ar(+) ions; Multiphoton ... |
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| Molecular Structure of Triaminoguanidine (TAG) |
OCT 87 |
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| Authors:
A. J. Bracuti; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER DOVER NJ ARMAMENT ENGINEERING DIRECTORATE
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| A single-crystal x-ray diffraction investigation of triaminoguanidine (TAG) was conducted. Lattice parameters, crystal structure, and molecular structure were determined. Structural comparisons were made between the TAG molecule and the TAG cation. |
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| The Orbital-Overlap Factor in Electron Transfer. Sensitivity of Homogeneous Self-Exchange Kinetics for Some Metallocenes to Electronic Structure |
25 SEP 87 |
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| Authors:
Roger M. Nielson; M. N. Golovin; George E. McManis; Michael J. Weaver; PURDUE UNIV LAFAYETTE IN DEPT OF CHEMISTRY
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| Rate constants, k(h)(ex), for the electron self exchange of cobaltocenium-cobaltocene, Cp2Co(+/o), and for the decamethyl derivative (Cp- Me5)2Co(+/0) obtained by using the NMR line broadening technique in acetonitrile and dimethylsulfoxide are compared with corresponding data for the ferrocene couples Cp2Fe(+/0) and (Cp-Me5)(2)Fe(+/0) and bis(benzene)chromium (I)/(O). The rate constants in a given solvent display and marked sensitivity to the reactant structure, the kh(ex) values being about tenfold larger for Cp2Do(+/0) relative ... |
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| Synthesis, NMR Characterization and Electrical Properties of Siloxane- Based Polymer Electrolytes |
24 AUG 87 |
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| Authors:
R. Spindler; D. F. Shriver; NORTHWESTERN UNIV EVANSTON IL DEPT OF CHEMISTRY
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| A crosslinked siloxane-based polymer has been prepared by the reaction of Poly(methylhudrosiloxane), monomethyl ether poly(ethylene glycol), and poly(ethylene glycol). The polymer, which has been structurally characterized by 29 Si NMR, forms complexes with LISO CF3 that exhibit good ionic conductivities (for a LiSO3CF3 15 wt% complex). The polymer and its salt complexes have been characterized by elemental analysis, 29 Si NMR powder diffraction X-ray powder diffraction, DSC, and AC complex ... |
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| Purified Mojave Toxin Interacts with CA++Mg++ ATPase in Rat Synaptic Membranes |
AUG 87 |
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| Authors:
James P. Chambers; Matthew J. Wayner; James J. Valdes; TEXAS UNIV AT SAN ANTONIO DIV OF LIFE SCIENCES
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| Calcium mediated channels produce changes in intracellular calcium concentration in neural, skeletal, and cardiac tissues. The Ca Mg ATPase is the enzyme responsible for maintaining the Ca gradient across the membrane. Studies of these Ca dependent membrane proteins have been limited due to the scarcity of naturally occuring toxins with which to probe the systems. In this report, we describe the actions of Mojave toxin, an acidic toxin isolated from ... |
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| The Analysis of Metal Finishing Solutions by Ion Chromatography |
AUG 87 |
220 pages |
| Authors:
Samuel Sopok; ARMY ARMAMENT RESEARCH, DEVELOPMENT AND ENGINEERING CENTER WATERVLIET NY BENE T WEAPONS LAB
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| Ion chromatography is very effective for ionic and polar species determinations. Separation of the analyste into pure peaks simplifies detection compared to detecting the same species in the unseparated sample matrix. One of the methods provides important improvements on existing methods, while the rest provide new and improved ways to analyze metal finishing solutions. The advantages of these methods are that considerable improvements were made in the areas of: trace ... |
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| Investigation of the Biologic Activity and Structure Function Relationships of Synthetic Polymers Which Act as Hormones, Behavior Modifiers and Thymic Immunomodulators |
15 JUL 87 |
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| Authors:
Robert L. Hunter; Irene J. Check; Darryl B. Neill; EMORY UNIV ATLANTA GA
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| This project attempts to probe interrelationships between the central nervous, immune and endocrine systems. The key departure was the discovery that certain synthetic copolymers stimulate hyperplasia of cortical lymphocytes in the thymus and increased motor behavior. These copolymers, investigations suggested that these copolymers might mimic the activity of neuropeptides either by interacting with their receptors or by modifying cation fluxes across cell membranes. The experiments in this project have been ... |
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| Correlation of Spectroscopic and Magnetic Data of Two Charge Transfer Compounds of TCNQ with Cationic Copper Chelates |
10 JUL 87 |
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| Authors:
Michael Schwartz; William E. Hatfield; NORTH CAROLINA UNIV AT CHAPEL HILL DEPT OF CHEMISTRY
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| Spectral data for (Cu(en)2) (TCNQ)2 reveal a TCNQ charge transfer band at 1220 nm. The lack of a contribution of paramagnetism from TCNQ(-) to that of (Cu(en)2) (TCNQ)2 is understood since a system with E sub ST of 0.12 eV would exhibit a magnetic susceptibility of .00001 emu/mole at 300 K. The magnetic susceptibility of (Cu(en)2) (TCNQ)2 indicates that one-third an electron is transferred from TCNQ- to (Cu(phen)2) (2+), and ... |
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| Asphalt-Aggregate Interactions in Hot Recycling |
JUL 87 |
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| Authors:
Badru M. Kiggundu; J. K. Newman; NEW MEXICO ENGINEERING RESEARCH INST ALBUQUERQUE
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| This report summarizes results of an investigation of asphalt aggregate interactions in hot recycled systems. Materials used in the research included a severe stripping aggregate and a nonstripping aggregate. Both were evaluated using the Lottman 70 percent retained tensile strength criteria. Additional materials included a 40/60 RAP new aggregate system, one virgin asphalt, two RAP recovered binders, one modifier or recycling agent, and two blends. The modifier was selected using ... |
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| Applications of Multivalent Ionic Conductors to Polymeric Electrolyte Batteries |
JUL 87 |
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| Authors:
J. Y. Cherng; B. B. Owens; W. H. Smyrl; M. Z. Munshi; MINNESOTA UNIV MINNEAPOLIS DEPT OF CHEMICAL ENGINEERING AND MATERIALS SCIENCE
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| Fast ion conduction has been demonstrated in certain polymer materials doped with an alkali metal salt. Recently divalent salts have also been used in the preparation of ionically conducting polymers. Certain complexes were found to be anion conductors while others were cation conductors. It is therefore of interest to study the reasons for the apparent difference. Alternating current measurements are currently being evaluated on a number of polymer divalent salt ... |
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| The Isolation of the Free-Base of the Triaminoguanidinium Ion |
JUN 87 |
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| Authors:
A. J. Bracuti; C. Y. Manning; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER DOVER NJ ARMAMENT ENGINEERING DIRECTORATE
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| A non-aqueous cation exchange method was developed for the preparation and isolation of the highly air-sensitive free-base of the triaminoguanidinium ion. Elemental analysis performed on the free-base indicated its composition was triaminoguanidine rather than triaminoguanidinium hydroxide. |
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| Cation or Solvent-Induced Supermolecular Phthalocyanine Formation: Crown Ether Substituted Phthalocyanines |
JUN 87 |
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| Authors:
Nagao Kobacashi; Alfred B. Lever; YORK UNIV NORTH YORK (ONTARIO) DEPT OF CHEMISTRY
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| Phthalocyanies with four 15-crown-5 ether voids at the 3,4 positions (MtCRPc) (Mt = H2, Zn, Co, Ni and Cu) have been synthesized and characterised. Dimerization of MtCRPC is induced in solvents such as methanol and by addition of some cations (K(+), Ca(2+), and NH4(+), especially K(+). Cofacial dimer formation in the presence of these cations proceeds in a two-step three stage process, as indicated by absorption and emission spectroscopy. These ... |
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| Thermal and Dynamical Effects on Electrodynamic Space Tethers |
08 MAY 87 |
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| Authors:
John S. Prall Jr; ARMY MILITARY PERSONNEL CENTER ALEXANDRIA VA
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| Electrodynamic tethers are essentially long conducting wires which, when deployed from an orbiting satellite, can generate power by converting orbital mechanical energy into electrical energy for use on the satellite. They can accomplish this as a consequence of the electrodynamically induced voltage caused by the movement of the tether with respect to the earth's magnetic field; this acts to drive a current through the tether to an on-board load. Conversely, ... |
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| Sunflower Army Ammunition Plant NQ (Nitroguanidine) Wastewater Treatment GAC/IE (Granular Activated Carbon/Ion Exchange) Pilot Plant |
17 APR 87 |
60 pages |
| Authors:
A. A. Balasco; R. C. Bowen; E. L. Field; R. F. Machacek; L. R. Woodland; LITTLE (ARTHUR D) INC CAMBRIDGE MA
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| The report describes a program to characterize the performance of a granular activated carbon/ion exchange (GAC/IE) pilot plant system for removing pollutants from the various wastewaters of a nitroguanidine (NQ) production plant. This program was carried out at the Sunflower Ammunition Plant, DeSoto, Kansas, from January through May 1986. It was found that carbon beds can efficiently remove NQ from any of the wastewaters tested, that cation exchange beds can ... |
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| China Report, Political, Sociological and Military Affairs, PRC State Council Bulletins, No. 9, 20 Apr.; No. 10, 30 Apr; No. 11, 10 May; No. 12, 20 May 1986 |
16 APR 1987 |
22 pages |
| Authors:
JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA
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| China Report, Political, Sociological and Military Affairs, PRC State Council Bulletin, No. 7, 31 March 1986 |
14 APR 1987 |
21 pages |
| Authors:
JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA
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| China Report, Political, Sociological and Military Affairs, PRC State Council Bulletins, No. 3, 20 Feb; No. 4, 28 Feb; No. 5, 10 Mar 1986 |
11 APR 1987 |
18 pages |
| Authors:
JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA
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| A Compact Digital Communications System. Part 3. Generalising the Phase Locked Loop. Memorandum rept. |
APR 87 |
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| Authors:
J. A. Pritchard; ROYAL SIGNALS AND RADAR ESTABLISHMENT MALVERN (ENGLAND)
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| We describe a generalisation of the phase locked loop principle which eliminates the problem of carrier recovery when applied to phase shift signals. The system is tolerant of signal fading and shows orders of magnitude improvements in pull in range and tracking performance over current systems used in satcoms. Pull in range exceeds 150 Hz in an absolute signal to noise ratio of worse than -10 dB. The loop will ... |
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| The Hueckel Model for Small Metal Clusters. 3. Anion Structures and HMO (Hueckel Molecular Orbital) Electron Affinities |
APR 87 |
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| Authors:
D. M. Lindsay; Lin Chu; Youqi Wang; Thomas F. George; STATE UNIV OF NEW YORK AT BUFFALO DEPT OF CHEMISTRY
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| The most stable structures for the alkali-like clusters M3-Mg- are calculated within the framework of the simple Huckel model. The Huckel geometries are, on average, slightly less compact than those of the neutral and cation clusters, a phenomenon which may be related to the additional electronic kinetic energy of the anions. Cluster compactness is quantified by an estimation of 'soft sphere' volumes, which also allows for a comparison of classical ... |
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| Investigation of Sheath Phenomena in Electronegative Glow Discharges |
APR 87 |
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| Authors:
Gary L. Duke; AIR COMMAND AND STAFF COLL MAXWELL AFB AL
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| Investigates sheath phenomena in electronegative glow discharges. Calculations have been performed for He/HC1, Ar/HC1, and Xe/HC1 mixtures to model the cathode fall region of a gas discharge. The electric field, Townsend ionization and attachment coefficients, as well as positive ion, negative ion, and electron densities were were calculated as a function of distance. Attachment was found to increase the voltage and length of the cathode fall. Efficient ionization of the ... |
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| China Report, Political, Sociological and Military Affairs, PRC State Council Bulletins, Nos. 33-34, 10, 20 December 1985 |
30 MAR 1987 |
17 pages |
| Authors:
JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA
|
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| Chemiluminescence from AqueousMicellar Systems |
24 MAR 87 |
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| Authors:
A. P. Schaap; WAYNE STATE UNIV DETROIT MICH DEPT OF CHEMISTRY
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| A. Chemical and Enzymatic Triggering of 1,2-Dioxetanes A series of dioxetanes which are thermally stable at ambient temperature but which can be triggered for efficient chemiluminescence on demand by the addition of the appropriate chemical catalyst or enzyme have been discovered the process involves the removal of a protecting group from a stable form of the dioxetane to generate an unstable aryloxide intermediate which decomposes spontaneously to yield the luminescence. ... |
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| Electronics and Ionic Transport in Polymers |
15 MAR 87 |
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| Authors:
Martin Pomerantz; John R. Reynolds; Krishnan Rajeshwar; Dennis S. Marynick; Timothy D. Shaffer; TEXAS UNIV AT ARLINGTON DEPT OF CHEMISTRY
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| Ion transport studies of the 'self-doped' copolymer, poly(pyrrole-co- 3-(pyrrol-1-yl)propane sulfonate have shown that lithium mobility is 50% higher than butyl nitride. Polymerizaton of 3-(pyrrol-1-yl) propane sulfonate with ferric chloride has provided a water soluble polymer. A study of anodic polymerization of pyrrole using a quartz crystal microbalance, set up to be used in solution, shows poor polymerization efficiency at the beginning but improves as the reaction proceeds. The band gap ... |
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| Photoionization Technique for Growth of Metallic Films. |
10 MAR 1987 |
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| Authors:
James G. Eden; David B. Geohegan; DEPARTMENT OF THE AIR FORCE WASHINGTON DC
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| A novel method and system for depositing films of selected metallic or semiconductor materials, and particularly of the group III, IV, and V elements is described which comprises heating a halide compound of the material to produce vapor within a substantially closed chamber, irradiating the vapor with light of preselected wavelength to dissociatively photoionize the vapor into the constituent positive ions of the material and negative halogen ions, and subjecting ... |
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| Ion-Exchanged Waveguides for Signal Processing Applications - A Novel Electrolytic Process |
07 MAR 87 |
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| Authors:
R. V. Ramaswamy; FLORIDA UNIV GAINESVILLE DEPT OF ELECTRICAL ENGINEERING
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| Ion exchange process and technology for fabrication of optical waveguides has been studied systematically to improve the reproducibility and establish the correlation between the process parameters and the component characteristics. Two-step process has been studied extensively and used for fabrication of low-loss fiber-compatible single-mode buried channel waveguides using the Na+ - Ag+ cation pair. Nonlinear waveguides have been studied theoretically and some of the predictions have been verified experimentally in ... |
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| Evaluation of Resins Cured by Ultraviolet Radiation and in Conjunction with Fiber Optic Systems for Use in the Field Repair of Composite Materials |
MAR 87 |
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| Authors:
Michael S. Sennett; Stanley E. Wentworth; ARMY LAB COMMAND WATERTOWN MA MATERIAL TECHNOLOGY LAB
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| Several commercially available resins designed to be cured with ultraviolet radiation were evaluated with respect to their potential for use in the field repair of composite materials. Thermal and mechanical properties of cured resins were evaluated by DSC and TBA techniques. Some cured resins exhibited physical properties which may be suitable for repair application. None of the tested materials was able to cure when impregnated in woven graphite cloth which ... |
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| An Examination of the Structural Features of Triaminoguanidinium 5- Aminotetrazolate Monohydrate |
MAR 87 |
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| Authors:
A. J. Bracuti; J. M. Troup; Michael Extine; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER DOVER NJ ARMAMENT ENGINEERING DIRECTORATE
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| The crystal structure of triaminoguanidinium 5-aminotetrazolate monohydrate was determined with 3-D x-ray diffraction data. The monoclinic structure (C 2/c) has unit-cell parameters: a = 10.448(2),b = 10.387(1), c = 15. 514(3)A, and beta = 93.11(1) degrees. The structure consists of of ions and water molecules packed in hydrogen bonded helicoidal chains which are laterally hydrogen bonded to form an infinite 3-dimensional network. In the cation, strict planarity is only observed ... |
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| Laboratory Studies of Atomic Collision Processes |
26 FEB 87 |
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| Authors:
R. Johnsen; M. A. Biondi; PITTSBURGH UNIV PA DEPT OF PHYSICS
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| Accomplishments: Dissociative recombination of O4(+) ions with electrons as a function of electron temperature. Development of computer codes to describe electron-energy gain and loss processes in plasmas heated by microwaves, including effects of inelastic collisions with molecules and spatially non uniform fields. Development of the rf conductivity method to determine electron and ion densities in plasmas at atmospheric neutral densities. Development of mass spectrometric techniques to analyze the ion composition ... |
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| Tests of a Model for Macromolecular Migration on Myoblast Cell Surfaces Exposed to Alternating Electric Fields |
22 JAN 87 |
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| Authors:
Lin-Liu Sen; Asher R. Sheppard; LOMA LINDA UNIV CALIF
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| The proposal that low frequency alternating electric fields may cause a net displacement of charged cell surface molecules similar to the effect observed with static electric fields is tested. Spherical myoblasts obtained from cultured embryos of Xenopus laevis were exposed for 30 min to static fields (2.5 to 9.5 V/cm) and for 30 to 75 min to 10- and 60-Hz electric fields in the range 18 toi 34 V/cm sub ... |
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| Dependence of the Reaction Probability of Benzene on the Size of Gaseous Niobium Clusters |
14 JAN 87 |
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| Authors:
R. J. St. Pierre; M. A. El-Sayed; CALIFORNIA UNIV LOS ANGELES DEPT OF CHEMISTRY AND BIOCHEMISTRY
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| Small niobium atomic clusters (Nbx, x = 1-15), synthesized by laser vaporization in a supersonic molecular beam system, are mixed with benzene in a fast flow reactor and detected by excimer laser photoionization time-of-flight mass spectrometry. The ratio of the observed mass peak ion intensity of NbxC6 to that of NbxC6H6 + NbxC6 at low excimer laser intensities is used as a measure of the observed conversion of NbxC6H6 into ... |
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| Parallel Algorithms for Computer Vision |
JAN 87 |
|
| Authors:
Tomaso Poggio; James Little; MASSACHUSETTS INST OF TECH CAMBRIDGE
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| The general goals of this research effort is to explore the potential applications and performance of fine grained computer architectures for vision. The body of this report gives a brief overview of the results of the research during the first twelve months of effort. A taxonomy of parallel vision algorithms has been refined. Parallel versions of several Class 1 algorithms (for early vision, directly derived from regularization methods) have been ... |
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| Polymeric Electrolytes |
87 |
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| Authors:
P. M. Blonsky; S. Clancy; L. C. Hardy; C. S. Harris; R. Spindler; NORTHWESTERN UNIV EVANSTON IL MATERIALS RESEARCH CENTER
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| Research on solvent-free polymer electrolytes is currently very active, because of their potential applications in high energy density batteries, specific ion sensors, electrochromic displays, and other electrochemical devices. Pure ionic and mixed ionic-electronic conducting polymer-salt complexes will be discussed in this report. Vibrational spectroscopy, X-ray diffraction and EXAFS spectroscopy studies have provided structural information on PEO-salt complexes. For the sodium and lithium complexes, the cations are coordinated to the polyether ... |
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| Purification, Structure and Properties of Escherichia coli tRNA pseudouridine Synthase 1 |
87 |
|
| Authors:
Harold O. Kammen; Christopher C. Marvel; Larry Hardy; Edward E. Penhoet; CALIFORNIA UNIV OAKLAND NAVAL BIOSCIENCES LAB
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| The RNA modification enzyme, tRNA pseudourine synthase I (PSUI) has been isolated in 95% purity from an Escherichia coli strain harboring multicopy plasmid with a 2.3kb insert for the hisT operon. Its molecular size, amino acid composition and N-terminal sequence correspond to those predicted by the structure and expression of the hisT gene. Enzyme activity, as measured by a 3H release assay, is unaffected by pretreatment if PSUI with micrococcal ... |
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| Liquid Crystalline Polyethers |
87 |
|
| Authors:
Virgil Percec; CASE WESTERN RESERVE UNIV CLEVELAND OH DEPT OF MACROMOLECULAR SCIENCE
|
| The first part of this paper will review recent work from our laboratory on structural principles and their use in the synthesis of thermotropic-lyotropic main chain liquid crystalline (LC) polyethers. Two synthetic procedures, i.e., phase transfer catalyzed polyetherification and cationic ring opening polymerization of bridged bicyclic ethers will be described, and examples will be provided for the synthesis of polyethers containing flexible spacers, adn of quasirigid polyethers. A detailed discussion ... |
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| Liquid Crystalline Copoly(vinylether)s Containing 4(4')-Methoxy-4'(4)- Hydroxy-Alpha-Methylstilbene Constitutional Isomers as Side Groups |
87 |
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| Authors:
Virgil Percec; Dimitris Tomazos; CASE WESTERN RESERVE UNIV CLEVELAND OH DEPT OF MACROMOLECULAR SCIENCE
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| Ethoxy vinyl ethers containing 4-methoxy-4'-hydroxy-alpha- methylstilbene and 4-hydroxy-4'-methoxy-alpha-methylstilbene constitutional isomers as side groups were synthesized by phase transfer catalyzed etherification of a mixture containing the above mentioned isomers with 2- chloroethylvinyl ether. Cationic copolymerization of various ratios between the two constitutional isomeric monomers led to a mixture of two copolymers which were separated by fractional precipitation. One copolymer exhibits a nematic mesophase, the other exhibits two smectic mesophases. |
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| Color Removal Using Alum and Cationic Polymers |
DEC 86 |
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| Authors:
Randall L. Cooper; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF CIVIL ENGINEERING
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| Color in natural waters is often due to the presence of humic materials. Humic materials may be precursors for trihalomethanes (THM's)in water that is chlorinated for disinfection. The removal of humic compounds before chlorination of drinking water helps to prevent the formation of THM's. A common operation employed to lower the humic content or color of a natural water is that of coagulation, with alum and synthetic polymers being common ... |
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| Development of Assay Methods for Liquid Propellants |
DEC 86 |
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| Authors:
Nollie Swynnerton; Henry Hamil; William O. Seals; SOUTHWEST RESEARCH INST SAN ANTONIO TX
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| A feasibility study determined that mobile phase ion chromatography (MPIC) and high performance ion chromatography, (HPIC) can identify and quantify the components of a liquid propellant. MPIC used a Dionex ion chromatograph equipped with a cation fiber suppressor and electrochemical and conductivity detectors in series. Sharp peaks were detected for the hydroxylamine and triethanolamine in LP 1845. In this sample, 252.7 ppm hydroxylammonium nitrate (86.9 ppm as free hydroxylamine) and ... |
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| Functional Consequences of Chemical Modification of the Saxitoxin Binding Site on Neuronal Sodium Channels |
31 OCT 86 |
16 pages |
| Authors:
Bruce K. Krueger; Robert J. French; MARYLAND UNIV BALTIMORE SCHOOL OF MEDICINE
|
| Voltage-dependent, saxitoxin-(STX-) sensitive sodium channels from rat brain are being studied at the single channel level in artificial planar phospholipid bilayer membranes. In the presence of the activating neurotoxin, batrachotoxin, the channels are selective for sodium over other cations, are blocked by nanomolar extracellular STX and are more likely to be open at depolarized membrane potentials. The carboxyl-specific reagent, trimethyloxonium, renders the channels insensitive to STX, reduces the rate of ... |
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| Synthesis and Characterization of New Low-Dimensional Metal Complex Conductors |
01 OCT 86 |
|
| Authors:
William E. Hatfield; NORTH CAROLINA UNIV AT CHAPEL HILL DEPT OF CHEMISTRY
|
| This research program was devoted to the synthesis and characterization of new transition metal compounds which had the potential of high electrical conductivities. Since band formation and electrical conductivity is enhanced by strong intermolecular interactions fully and partially oxidized metallomacrocyclic complexes were synthesized and characterized. Electrochemical methods were developed for crystal growth to overcome solubility problems which led to mixed phase products in earlier studies. These principles were extended to ... |
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| Cationic Polymerizations of 1,3,,6-Trioxocane and 2-Butyl-1,3,6- Trioxocane |
01 OCT 86 |
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| Authors:
James C. Chien; Baobei Xu; C. P. Lillya; MASSACHUSETTS UNIV AMHERST DEPT OF POLYMER SCIENCE AND ENGINEERING
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| The polymerization of 1,3,6-trioxocane (TOC) has been reinvestigated. The reaction occurs without an introduction period to give high MW linear polymers. The degree of polymerization is not independent of conversion. Polymers having M sub n as high as 81,000 and M sub w/M sub n approx. 1.4 and with very strong mechanical strength can be obtained. These results contrast with earlier reports of long induction periods and products with M ... |
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| Salt Effects in Photoinduced Electron Transfer Reactions |
14 SEP 86 |
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| Authors:
Gary B. Schuster; Barbara Goodson; ILLINOIS UNIV AT URBANA ROGER ADAMS LAB
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| Metal salts and oxygen react synergistically to inhibit back electron transfer in photoinduced reactions. Keywords: Electron transfer; Cation; and radical. |
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