| Vibrational Energy in Molecules and Nanoparticles: Applications to Energetic Materials |
30-Jan-2009 |
11 pages |
| Authors:
Dana D Dlott; ILLINOIS UNIV AT URBANA-CHAMAPIGN
|
 | This report documents progress made by the Dlott group at the University of Illinois during the 32 month period of this AFOSR award. time, and also thee |
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| Demonstration of Lightweight Engineering Solutions for a Low-Cost Safe Explosive Ordnance Destruct Tool |
DEC 2007 |
147 pages |
| Authors:
Pedro J. Freitas; David M. Gerace; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| The continued development of a low-cost and safe method for neutralizing explosive threats is reported. The concept depends on the use of pure nitromethane in a totally encased lightweight plastic shaped charge and the in situ injection of a minute quantity of diethylenetriamine just prior to employment. Penetration and impact initiation capabilities of a baseline charge as well as function reliability were previously demonstrated. The jet from a previously developed ... |
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| Using Quantum Mechanics to Predict Shock Properties of Explosives |
NOV 2006 |
7 pages |
| Authors:
N. A. Romero; W. D. Mattson; B. M. Rice; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| The almost exponential increase in computer power over the last few decades has opened up the venue for increasingly more advanced and accurate computer simulations. As little as ten years ago, quantum mechanical calculations were restricted to predictions of static properties of systems containing tens of atoms, thus limiting first principles explorations to gas phase chemical and physical processes. With today's computers, quantum mechanical calculations can easily be performed for ... |
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| Meso and Micro Scale Propulsion Concepts for Small Spacecraft |
14 JUN 2005 |
26 pages |
| Authors:
R. A. Yetter; V. Yang; I. A. Aksay; F. L. Dryer; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL AND NUCLEAR ENGINEERING
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| A meso/micro scale liquid propellant thruster is being developed for small spacecraft. In this thruster, the liquid propellant was injected directly into the chamber tangentially along the combustor wall. Heat feedback from the flame, once ignited, decomposed and gasified the liquid propellant. The gasification process of the propellant produced a voflex flow in the combustor, which stabilized the gas- phase flame. Modeling studies with gas-phase injection of reactants have shown ... |
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| Meso and Micro Scale Propulsion Concepts for Small Spacecraft |
24 DEC 2004 |
50 pages |
| Authors:
R. A. Yetter; V. Yang; I. A. Aksay; F. L. Dryer; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MECHANICAL AND NUCLEAR ENGINEERING
|
| A meso/micro-scale liquid propellant thruster was designed and developed for small spacecraft. Gas-phase combustion was stabilized in small combustion chambers (approx. 10-200 cu mm) using vortex flows. For liquid propellant steady-state operation, the propellant was injected directly into the chamber tangentially along the combustor wall. Heat feedback from the flame, once ignited, decomposed and gasified the liquid propellant. Although the propellant of interest was a HAN-based liquid propellant, initial studies ... |
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| An Ab Initio Study of Solid Nitromethane, HMX, RDX, and CL20: Successes and Failures of DFT |
DEC 2004 |
9 pages |
| Authors:
Edward F. Byrd; Cary F. Chabalowski; Gustavo E. Scuseria; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Using the PW91 and PBE density functional theories (DFT), we have studied four energetic molecular crystals: nitromethane, HMX, RDX, and CL20 with a wide range of basis sets. Our goal is to assess the accuracy of DFT when applied to organic molecular crystals (such as energetic materials) as scientists are beginning to include this methodology in energetic materials research without knowledge of the limitations of the method. Intramolecular distances, simple ... |
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| First Principles Calculations of the Adsorption of Nitromethane and 1,1- Diamino-2,2-dinitroethylene (FOX-7) Molecules on Al2O3(0001) Surface |
AUG 2004 |
54 pages |
| Authors:
Dan C. Sorescu; Jerry A. Boatz; Donald L. Thompson; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
|
| First-principles calculations based on density functional theory (DFT) and the generalized gradient approximation (GGA) have been used to study the adsorption of nitromethane (NM) and 1,1-diamino-2,2-dinitroethylene (FOX-7) molecules on the basal plane of an alpha-Al2O3 crystal. The calculations employ a (2x2) supercell slab model and 3D periodic boundary conditions. Based on these calculations we have determined that both NM and FOX-7 molecules can adsorb nondissociatively on the surface with the ... |
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| First-Principles Calculations of the Adsorption of Nitromethane and 1,1- Diamino-2,2-dinitroethylene (FOX-7) Molecules on the Al(111) Surface |
31 MAR 2003 |
33 pages |
| Authors:
Dan C. Sorescu; Jerry A. Boatz; Donald L. Thompson; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| First-principles calculations based on spin-polarized density functional theory (DFT) and the generalized gradient approximation (GGA) have been used to study the adsorption of nitromethane (NM) and 1,1-diamino-2,2- dinitroethylene (FOX-7) molecules on the Al(111) surface. The calculations employ (3x3) aluminum slab geometries and 3D periodic boundary conditions. Based on these calculations, we have determined that both dissociative and nondissociative adsorption mechanisms are possible, depending on the molecular orientation and the particular ... |
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| Theoretical Chemical Dynamics Studies of the Decomposition of Cyclic Nitramines |
30 JUN 2002 |
6 pages |
| Authors:
Donald L. Thompson; OKLAHOMA STATE UNIV STILLWATER DEPT OFCHEMISTRY
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| Research performed over the period April 1, 2001 - June 30, 2002 supported by the U.S. Army Research Office (Contract No.: DAAD19-01-1-0022) is described. This research program is concerned with the development of theoretical and computational methods and studies fundamental processes in energetic materials. The work during this report period focused on the following: (1) Molecular dynamics simulations of liquid nitromethane. (2) Simulations of the photodissociation of methyl nitrite on ... |
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| Destruction of Energetic Materials in Supercritical Water |
25 JUN 2002 |
217 pages |
| Authors:
S. J. Buelow; D. Allen; G. K. Anderson; F. L. Archuleta; J. H. Atencio; LOS ALAMOS NATIONAL LAB NM
|
| This effort was a survey of the compatibility of a broad series of representative energetic materials (EM) commonly used in propellants, munitions and explosives with a proposed process of controlled decomposition in water near or above the critical temperature (approximately 373 CC), Central issues, in order of consideration, are safety, environmental compatibility of decomposition products, destruction efficiency, extrapolation to compounded formulations of EM, and engineering considerations for scale-up to full-scale ... |
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| First Principles Calculation of the Chemisorption Properties of Nitro- Containing Molecules on the Al(111) Surface (Multiscale Simulations of High Energy Density Materials Challenge Project) |
17 MAY 2002 |
9 pages |
| Authors:
Dan C. Sorescu; Jerry A. Boatz; Donald L. Thompson; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE WEST
|
| First-principles calculations based on spin-polarized density functional theory (DFT) and the generalized gradient approximation (GGA) have been used to study the adsorption of nitromethane (NM), 1,1-diamino-2,2- dinitroethylene (FOX7) and 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) on Al(111) surface. The calculations employ aluminum slab geometries and 3D periodic boundary conditions. Three surface models have been considered in these studies. |
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| Simulations of Energetic Materials for Rocket Propulsion: Obtaining More "Bang for the Buck" |
29 APR 2002 |
5 pages |
| Authors:
Dan C. Sorescu; Donald L. Thompson; Jerry Boatz; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE WEST
|
| Powderized aluminum has long been used as an energetic ingredient in rocket propellant formulations, comprising approximately 15-20% of some conventional ammonium perchlorate solid propellant formulations. However, the performance of aluminum is reduced by the rapid formation of an aluminum oxide overcoat on aluminum particles prior to combustion, which also inhibits efficient burning. Furthermore, formation of the oxide overcoat severely reduces the potential advantages of using high surface-to-volume-ratio ultrafine aluminum particles, ... |
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| The Mechanism and Dynamics of Explosive Combustion in Aerosol Fuels |
NOV 2001 |
5 pages |
| Authors:
Roger Miller; Tomas Baer; NORTH CAROLINA UNIV AT CHAPEL HILL DEPTOF CHEMISTRY
|
| Our initial experiments explored the mechanism of vaporization/ ionization in liquid and nitrobenzene aerosols using CO2 laser evaporation and 193 run excimer laser ionization. Those experiments were critical in characterizing the capabilities of our apparatus and in laying the framework for the behavior of non-reactive species in our two-laser design. The use of multi- photon ionization schemes with the excimer laser resulted in highly fragmented mass spectra, making the identification ... |
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| Laser Initiated Decomposition in Aerosol Fuels: A Method for Probing the Early Stages of Ignition and Detonation |
SEP 2001 |
6 pages |
| Authors:
Roger E. Miller; Tomas Baer; NORTH CAROLINA UNIV AT CHAPEL HILL DEPTOF CHEMISTRY
|
| The DURIP grant has been used to purchase two new infra-red laser systems that have been used to initiate combustion of energetic aerosol particles. One is a CO2 laser capable of delivering up to 1.5 J of pulsed power, while the other is an OPO laser pumped by an existing Nd:YAG laser to provide tunable radiation in the 2.7 to 3.3 micrometers range. These lasers have been used to help ... |
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| The Mechanism and Dynamics of Explosive Combustion in Aerosol Fuels |
15 AUG 2000 |
5 pages |
| Authors:
Roger E. Miller; Tomas Baer; NORTH CAROLINA UNIV AT CHAPEL HILL DEPTOF CHEMISTRY
|
| This project investigates the explosive combustion of aerosol fuels using a single particle mass spectrometer. Initiating explosive reactions of small samples (-l0(-12) grams) in vacuum allows the intermediate products of the reaction to escape into a collisionless region where we detect them using laser spectroscopy. Recent results from our laboratory explore the mechanism of amine sensitization in nitromethane. We initiate the decomposition of nitromethane/ diethylamine ... |
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| The Mechanism and Dynamics of Explosive Combustion in Aerosol Fuels |
11 JUL 2000 |
5 pages |
| Authors:
Roger E. Miller; Tomas Baer; NORTH CAROLINA UNIV AT CHAPEL HILL DEPTOF CHEMISTRY
|
| This project investigates the explosive combustion of aerosol fuels using a single particle mass spectrometer. Initiating explosive reactions of small samples (tilde 10 to the -12 grams) in vacuum allows the intermediate products of the reaction to escape into a collisionless region where we detect them using laser spectroscopy. Recent results from our laboratory explore the mechanism of amine sensitization in nitromethane. We initiate the ... |
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| Initiation of Energetic Solids: The First Nanosecond |
31 MAR 1999 |
9 pages |
| Authors:
Dana D. Dlott; ILLINOIS UNIV AT URBANA
|
| The goal is to understand what occurs at the molecular level during shock initiation of energetic materials. We have developed the nanoshock technique, which lets us shock any solid material and study its molecules using ultrafast vibrational spectroscopy with 25 ps time resolution. Test experiments were conducted with anthracene to verify the performance of this technique, which was subsequently extended to energetic materials including RDX and NTO. A related theoretical ... |
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| The Mechanism and Dynamics of Explosive Combustion in Aerosol Fuels |
1999 |
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| Authors:
Roger E. Miller; Tomas Baer; NORTH CAROLINA UNIV AT CHAPEL HILL DEPTOF CHEMISTRY
|
 | This project investigates the explosive combustion of aerosol fuels using a single particle mass spectrometer. Initiating explosive reactions of small samples (^10 (exp -12) grams) in vacuum allows the intermediate products of the reaction to escape into a collisionless region where we detect them using laser spectroscopy. Recent results from our laboratory explore the mechanism of amine sensitization in nitromethane. We initiate the decomposition of ... |
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| Ignition, Combustion and Kinetics of Energetic Materials |
30 JUN 1998 |
45 pages |
| Authors:
K. K. Kuo; S. T. Thynell; T. B. Brill; V. Yang; T. A. Litzinger; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF NUCLEAR ENGINEERING
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| To develop a comprehensive model of nitramine propellant ignition and combustion, the appropriate numerical analysis was developed to solve both transient and steady state combustion, including detailed finite rate chemical kinetics, thermodynamic phase transition, and sub-surface reactions. The model was advanced to predict ignition phenomena. Modeling work was complemented by conducting various experiments. Using fast thermolysis, significant accomplishments were made in studies of the decomposition behavior of propellant ingredients, such ... |
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| Energetic Compounds for Use in Shaped-Charge, Follow-Through Devices |
MAR 97 |
29 pages |
| Authors:
John D. Sullivan Jr.; Abe Turetsky; EDGEWOOD RESEARCH DEVELOPMENT AND ENGINEERING CENTER ABERDEEN PROVING GROUND MD
|
| Six organic compounds (4,5-dihydro-3-nitroisoxazole, 2,2- dinitropropane, 1,1-dinitroethane, 1-3-dinitropropane, nitrocyclopropane, and trans-1,2-dinitrocyclopropane) were prepared for detonation testing. Sensitized nitromethane solutions of these compounds were detonated using plastic blocks to observe blast power. The volume of the crater in the observation block was measured: the larger the crater, the more powerful the detonation. A statistical treatment of the results was performed. 1,1-Dinitroethane and trans-1, 2- dinitrocyclopropane gave the most promising results. 1,3-Dinitropropane ... |
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| Energetic Compounds for Use in Shaped-Charge, Follow-Through Devices |
MAR 97 |
29 pages |
| Authors:
Peter A. Wade; John D. Sullivan Jr.; Abe Turetsky; BATTELLE COLUMBUS LABS RESEARCH TRIANGLE PARK NC
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| Six organic compounds (4,5-dihydro-3-nitroisoxazole, 2,2- dinitropropane, 1,1-dinitroethane, 1,3-dinitropropane, nitrocyclopropane, and trans-1,2-dinitrocyclopropane) were prepared for detonation testing. Sensitized nitromethane solutions of these compounds were detonated using plastic blocks to observe blast power. The volume of the crater in the observation block was measured: the larger the crater, the more powerful the detonation. A statistical treatment of the results was performed, 1,1 -Dinitroethane and trans-1, 2- dinitrocyclopropane gave the most promising results. ... |
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| Energy and State Resolved Studies of the Pathways of Molecular Decomposition |
21 AUG 96 |
20 pages |
| Authors:
F. F. Crim; WISCONSIN UNIV-MADISON DEPT OF CHEMISTRY
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| The report describes studies of molecular decomposition using molecular beam photodissociation with vacuum ultraviolet photoionization detection of products. Information on the energy release and decomposition pathways of nitromethane, nitrobenzene, and organometallic molecules come from these studies. |
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| Response of Energetic Solids to Heat and Shock Pulses |
FEB 96 |
6 pages |
| Authors:
Dana D. Dlott; ILLINOIS UNIV AT URBANA
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| The problem is to develop experimental methods for studying the first events in initiation of an energetic material by a shock wave, to develop a detailed understanding of how initiation occurs. Using advanced laser systems in our laboratory, we have developed techniques to reproducibly generate microshock waves in energetic materials. We have developed new techniques to probe the behavior of materials and molecules during the shock process. In order to ... |
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| Conductivities of Lithium Tris(trifluoromethanesulfonyl) Methide in Aqueous and Nonaqueous Solutions at 25 degree C |
FEB 96 |
18 pages |
| Authors:
Charles W. Walker Jr.; Mark Salomon; ARMY RESEARCH LAB FORT MONMOUTH NJ
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| In order to determine the solution properties of lithium tris(trifluoromethanesulfonyl) methide (LiMe) in water and the aprotic solvents acetonitrile (AN), propylene carbonate (PC), N,N-dimethylformamide (DMF), and nitromethane (MeNO2), conductance measurements have been carried out at 25 deg C. Molar conductivities at infinite dilution and ion pair association constants were obtained analyzing the experimental data with the Fuoss-Hsia conductance equation using the expansion of Fernandez-Prini and Justice with and without inclusion ... |
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| Study of the Compression Behavior of High Performance Fibers |
31 JAN 96 |
22 pages |
| Authors:
Satish Kumar; Malcolm B. Polk; GEORGIA TECH RESEARCH CORP ATLANTA
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| Compression behavior of pitch and PAN based carbon fibers and its dependence on structure and morphology has been studied. Structure development in PAN based fibers with heat treatment temperature has been followed using raman spectroscopy. Compressive strength of glassy resins has been studied. Crosslinking in the free annealed methyl pendant PBZT fibers have been verified using (13)C solid state NMR. Based on the axial compressive strength, torsional modulus, and transverse ... |
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| Calculations to Support the Design of a Seismic Source Test |
01 NOV 95 |
63 pages |
| Authors:
David M. O'Donnell; Michael W. McKay; SCIENCE APPLICATIONS INTERNATIONAL CORP SAN DIEGO CA
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| Two numerical simulations were performed with the 2-D RAGE code to examine potential designs for a proposed seismic source test. The first calculation simulated the original design of the proposed SHIST test which was intended to demonstrate the use of near-source instrumentation developed in the HYDROPLUS program along with near-field seismic instrumentation to evaluate the seismic source function for hard rock. The calculation modeled the explosion of a 20-ton sphere ... |
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| Spectroscopic Study of Reaction Intermediates and Mechanisms in Nitramine Decomposition and Combustion |
20 MAY 95 |
40 pages |
| Authors:
Marilyn B. Jacox; NATIONAL INST OF STANDARDS AND TECHNOLOGY GAITHERSBURG MD MOLECULAR PHYSICS DIV
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| The infrared spectra of reaction intermediates trapped in solid neon were studied in order to support the development of diagnostics for short-lived species which are reaction carriers in nitramine decomposition and combustion and to derive information about reactions which are important in the condensed- phase decomposition of nitramines. Nitromethane and monomethylnitramine were used as model compounds in these studies. Evidence was obtained for the formation of water complexes with both ... |
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| State Resolved Differential Cross Sections for Reactions Important to the Decomposition of Energetic Materials |
01 SEP 94 |
10 pages |
| Authors:
Paul L. Houston; CORNELL UNIV ITHACA NY DEPT OF CHEMISTRY
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| This final report describes the research whose goal was to develop a new technique for characterizing the velocity distributions of state-selected reaction products and to use this technique to study reactions of importance to the decomposition of energetic materials. In this technique, the three- dimensional product velocity distribution is determined by ionizing the appropriate species, waiting for a delay while the species separate along their trajectories, and then projecting the ... |
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| Liquid Explosive in Pipes |
JAN 94 |
25 pages |
| Authors:
John D. Sullivan; William B. Sunderland; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
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| A simple effective means of testing a liquid explosive in the field was conceived and demonstrated. The central idea was to contain the liquid explosive in plastic pipe and to utilize high speed photography to examine detonation characteristics. Because plastic pipe is a weak confinement, it does not promote detonation of liquid explosive. All the liquid explosives tested were amine-sensitized nitromethane mixtures. Photo diagnostics of the detonations were enhanced by ... |
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| On the Viability of Nitronic Acids in the Decomposition of Nitroaromatics: A Theoretical Study of Nitronic Acids |
AUG 93 |
70 pages |
| Authors:
Koop Lammertsma; ALABAMA UNIV IN BIRMINGHAM DEPT OF CHEMISTRY
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| The nitro aci-nitro, keto enol, and imine enamine tautomeric processes in nitromethane, acetaldehyde, and acetaldimine were investigated at the G1 level of theory, in nitroacetaldehyde, 2- nitroacetaldimine, and 3-nitropropene at MP4/6-31G*, in 2-nitroaniline, 2- nitrophenol, and 2-nitrotoluene at MP2/6-31 G*, and in 2,6-dinitroaniline, 2,6- dinitrophenol, 2,6-dinitrotoluene, 2,4,6-trinitroaniline (picramide), 2,4,6- trinitrophenol(picric acid, PA), and 2,4,6-trinitrotoluene (NT) at HF/6-31 G*. These studies demonstrate that the ease of tautomerization is in the order ... |
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| Sensitive Detection of Gas-Phase Nitro-Containing Energetic Materials Employing 226-nm Radiation |
JUL 93 |
30 pages |
| Authors:
Rosario C. Sausa; George W. Lemire; Josef B. Simeonsson; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
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| The development of a novel technique for sensing trace vapors of -NO2 containing compounds is reported. This technique is based on the use of one laser operating at 226 nm to both photofragment the target molecule and detect the characteristic NO fragment, formed from a rapid predissociation of NO2 by resonance-enhanced multiphoton ionization (REMPI) and/or laser-induced fluorescence (LIF) via its A2 sum (+)-X2Pi(0,0) band origin. The analytical utility of this ... |
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| Proceedings of International Detonation Symposium (10th), Held in Boston, Massachusetts on July 12 - 16, 1993 |
JUL 93 |
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| Authors:
OFFICE OF NAVAL RESEARCH ARLINGTON VA
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| Reacting Liquid Monopropellant Sprays-Experiments with High Velocity Full Cone Sprays in 33 MPa, 500 Degrees C Nitrogen |
DEC 92 |
63 pages |
| Authors:
Avi Birk; Michael McQuaid; Gary Bliesener; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
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| Experiments were conducted to elucidate the jet breakup, atomization, and combustion of liquid monopropellant sprays through the use of imaging and spectroscopic techniques. Hydroxylammonium nitrate (HAN) based monopropellants LGPI845 and LGPI898 were injected at velocities ranging from 100 to 240 m/s through circular orifices into 33-MPa 500 deg C nitrogen. Experiments with nitromethane, ethanol, and aqueous HAN and TEAN solutions were also conducted. Spray dynamics were recorded via high-speed cinematography. ... |
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| Solvent Dynamical Effects in Electron Transfer: Electrochemical-Exchange Kinetics of Sesquibicyclic Hydrazines as a Probe of Coupled Vibrational Activation |
OCT 92 |
39 pages |
| Authors:
Donald K. Phelps; Michael T. Ramm; Yichun Wang; Stephen F. Nelson; Michael J. Weaver; PURDUE UNIV LAFAYETTE IN DEPT OF CHEMISTRY
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| Rate constants for electrochemical exchange of three sesquibicyclic hydrazine-radical cation redox couples, k(e)(ex), obtained at mercury by means of phase-selective ac voltammetry, are reported in seven solvents - acetonitrile, acetone, nitromethane, N, N-dimethylformamide, dimethylsulfoxide, benzonitrile and methanol. The hydrazine couples - denoted here 1+/0, 2+/0, and 3+/0 - feature variations in the bridgehead alkyl groups; they each exhibit substantial high-frequency vibrational barriers (4.5-5 kcal mol-1) to electrochemical exchange. These system's ... |
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| Analytical Assessment of the Suitability of a Liquid Explosive Substitute for Shaped Charge Testing |
MAY 91 |
29 pages |
| Authors:
Steven M. Buc; SYSTEM PLANNING CORP ARLINGTON VA
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| In this analysis, a 95% nitromethane (NMe) and 5% diethylamine (DEA) liquid explosive is substituted into a BRL 3.3 inch 42 degree conical copper lined charge. The original charge is Octol loaded. Since NMe is less energetic, it is expected to give a reduced jet tip velocity, less jet mass, and lower overall jet kinetic energy. This would naturally follow from the use of a lower energy density explosive. The ... |
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| An Intermolecular H-O Potential for Methyl Rotations in Solid Nitromethane |
APR 91 |
34 pages |
| Authors:
Betsy M. Rice; S. F. Trevino; ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD
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| A reliable determination of the (H-O) intermolecular potential by which of nitromethane interact with each other is presented. This effort is based upon a body of experimental information which is available on the crystal structure and the rotational properties of the methyl group of the molecule in the solid state. The crystal structure is known in the temperature range of 4 to 233 K. The rotational properties of the methyl ... |
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| Patterned Etching of Infrared Detector Arrays |
19 MAR 91 |
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| Authors:
Andrew Freedman; AERODYNE RESEARCH INC BILLERICA MA
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| We have attempted to develop a patterned etching technique for infrared detector arrays based on photo-induced processes. The technique is based on the efficacy of methyl radical etching of II-VI compounds such as HgCdTe and CdTe. Methyl radicals were produced in a pattern above a HgCdTe substrate by photodissociation a radical precursor such as acetone or nitromethane using an excimer laser operating at 193 nm. Neither optical nor scanning electron ... |
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| Kinetics of Propellant Combustion and Muzzle Flash Reactions |
28 NOV 90 |
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| Authors:
Arthur Fontijn; RENSSELAER POLYTECHNIC INST TROY NY DEPT OF CHEMICAL ENGINEERING
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| Knowledge of the kinetics of reactions taking place during propellant burning is essential to the development of improved energetic materials. Models lacking such information are devoid of physical significance and are of little use in extrapolation from one system to another. In the present work an HTP (high-temperature photochemistry) reactor has been used to measure the kinetics of a number of individual reactions, identified as important in propellant combustion models. ... |
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| Fluorescent Probe Investigation of a Water-Soluble Polyphosphazene |
31 MAY 90 |
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| Authors:
C. E. Hoyle; P. Wisian-Neilson; P. M. Chatterton; M. A. Trapp; UNIVERSITY OF SOUTHERN MISSISSIPPI HATTIESBURG DEPT OF POLYMER SCIENCE
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| The fluorescent probes were utilized to investigate the microenvironment created by a water-soluble polyphosphazene copolymer in aqueous solution. The combination of intensity, wavelength shift, and vibrational analysis measurements of the three small molecule probes is used to postulate an environment at high pH (with no added electrolyte) which is similar in polarity to methanol. In the absence of excess small molecule electrolyte, negatively charged probes are repelled by the charge ... |
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| United States Air Force Research Initiation Program for 1988. Volume 2 |
APR 90 |
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| Authors:
Rodney C. Darrah; Claude Cavender; UNIVERSAL ENERGY SYSTEMS INC DAYTON OH
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| Partial contents: NMR studies of alkylammonium-chloroaluminate room- temperature electrolytes; Mechanistic studies on the thermal decomposition of NTO by high performance liquid chromatography; Aromatic nitrations in chloroaluminate melts; Calculated C-NO2 bond dissociation energies A MCSCF study of the rearrangement of nitromethane to methyl nitrate; Sodium as an electrode for chloroaluminate; Transient shock waves in a Mach 3 flow; Ab-initio and semi- empirical molecular orbital studies of energetic materials (Nitrogen heterocyclics) and ... |
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| Synthesis of Triisocyanate Curatives - II |
MAR 90 |
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| Authors:
Jeffrey W. Gilman; DAYTON UNIV OH RESEARCH INST
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| A new triisocyanate curative octyltriprimaryisocyanate, OCTYPI, was prepared from via a six-step synthesis. The triamine, TAPN a precursor to triisocyanatopropyl nitromethane, TIPN, an energetic triisocyanate curative was also prepared via a six-step synthesis. Various selective reduction methods for preparation of energetic triisocyanates were surveyed. Subject Terms: Isocyanate, Tri isocyanate, Curative, Crosslinking agent, Diphenylphosphoryl azide, DPPA, Alcohol, Amine, Phosgene. (JES) |
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| Solvent Relaxation in Electron-Transfer Reactions: Comparisons between Barrier-Crossing Dynamics in Water and Polar Aprotic Media |
01 JUL 89 |
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| Authors:
Roger M. Nielson; George E. McManis; Michael J. Weaver; PURDUE UNIV LAFAYETTE IN DEPT OF CHEMISTRY
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| Rate constants, k sub ex, for electron self exchange of three metallocene redox couples, carboxymethyl (cobaltocenium-cobaltocene) CpCO2Me2) 2Co+o, hydroxymethyl (ferrocenium-ferrocene) (Cp (dot) CpCH2OH)Fe+/o, and trimethylaminomethyl (ferrocenium-ferrocene) (Cp (dot) CpCH2NMe3)Fe2+/2, obtained using proton NMR line broadening, are utilized along with optical electron-transfer energies for the mixed-valence biferrocenylacetylene cation to obtain solvent-dependent frequencies, (Kappa sub el)(n sub n), in water relative to those in methanol and six aprotic solvents. While (Kappa sub ... |
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| Compendium of Nitromethane Data Relevant to the Tactical Explosive System (TEXS) Program |
APR 89 |
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| Authors:
J. Hershkowitz; B. M. Dobratz; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER DOVER NJ FIRE SUPPO RT ARMAMENT CENTER
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| A comprehensive search of the literature was conducted on nitromethane and hazards associated in its use. Each reference was reviewed and a summary provided. These summaries were grouped into the categories: Adiabatio compression, detonation, tests, change in properties, health hazards, and problems. Associated with use in the Tactical Explosive System (TEXS). A guide to the use of the compendium amd suggestions for research are included. |
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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 88 |
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| Authors:
Joyce J. Kaufman; JOHNS HOPKINS UNIV BALTIMORE MD
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| This report pertains to: 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, AB-Initio Multireference Coupled Cluster and Multireference CI Calculations for Protonation NH3 / Deprotonation NH4(+); MR-CC (Multireference-Coupled Cluster) - A state-of-the- theoretical-art multireference coupled cluster (for both closed and opened shell systems) was rewritten, ... |
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| Synthesis of Triisocyanate Curatives |
NOV 88 |
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| Authors:
Jeffrey W. Gilman; DAYTON UNIV OH RESEARCH INST
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| The objective of this task is the improvement of solid propellant systems through the synthesis of new polymeric propellant ingredients. This task is divided into three sub-tasks: Isocyanate Crosslinking Agents, Novel Energetic Binders, and Energetic Internal Plasticizers. To date our efforts have focused exclusively on the first sub-task. A new triisocyanate curative triisocyanatomethylethane, TIME, was prepared from trimethylolethane via a four step synthesis. The triol precursor to octyltriprimaryisocyanate, OCTYPI, was ... |
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| Experiments with Liquid Gun Propellants |
AUG 88 |
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| Authors:
J. D. Knapton; C. Watson; I. C. Stobie; G. Klingenberg; ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD
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| Closed chamber and gun firing tests on various liquid monopropellants were performed at the Fraunhofer-Institute (EMI-AFB) and the Ballistic Research Laboratory (BRL). The objectives of the study were twofold: (1) to investigate the ignition requirements of the propellants in both a closed chamber and a gun and (2) to investigate the combustion characteristics of the propellants, also in both a closed chamber and a gun. Pyrotechnic igniters were used in ... |
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| Contractors Meeting on Combustion Rocket Propulsion Diagnostics of Reacting Flow Held in Monrovia, California on 13-17 June 1988 |
13 JUN 88 |
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| Authors:
J. M. Tishkoff; M. A. Birkan; G. S. Roy; S. G. Lekoudis; CALIFORNIA INST OF TECH PASADENA DIV OF ENGINEERING AND APPLIED SCIENCE
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| Abstracts are given for research efforts on airbreathing combustion, rocket propulsion, and diagnostics of reacting flows. Keywords: Shear layers, Turbulence, Instability, Electromagnetic propulsion, Plasma propulsion, Erosion, Magnetoplasmadynamic thrusters, Fluid dynamics, Arcjet thrust chambers, Electrothermal propulsion, Laser thermal propulsion, Electric discharges, Chemical kinetics, Nitramines, Nitroform compounds, Solid propellants, Acoustic flow fields, Solid rocket combustion chambers, Acoustic waves. (aw) |
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| High-Molecular Compounds (Selected Articles) |
07 JAN 88 |
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| Authors:
FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH
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| The polymerization of methyl methacrylate (MMA) in the presence of nitroalkanes is accompanied by a decrease in spin-lattice relaxation time even in the absence of a monomer-to-polymer transformation, which is evidently linked to the participation of free radicals in the process. With the objective of elucidating the nature of these free radicals and developing some estimate of their concentration, we undertook to investigate the polymerization of MMA in the presence ... |
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| Material Properties Test Number 2. Data Report |
MAR 87 |
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| Authors:
William A. Kitch; Thomas F. Hayden III; Harry Bewley; Eric J. Rinehart; AIR FORCE WEAPONS LAB KIRTLAND AFB NM
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| As part of the Cratering and Related Effects -- Dry Soil (CARES Dry) Test program, the Air Force Weapons Laboratory conducted the MP no. 2 test. The purpose of the test was to determine the dynamic material properties of the soil in situ. The test consisted of a spherical charge buried 20 m deep, containing 20 tons of nitromethane. The soil surrounding the charge was instrumented with stress and velocity ... |
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| Synthesis and Chemistry of Polynitroalkanes and Polynitroolefins |
15 OCT 86 |
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| Authors:
Clifford D. Bedford; Jeffrey C. Bottaro; Robert J. Schmitt; SRI INTERNATIONAL MENLO PARK CA CHEMISTRY LAB
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| The objective of the current study was to develop new methods for carbon, nitroxides, and nitrogen bond formation. Below we summarize the results of there major research areas: (1) Nonacidic amine nitration. Two new nonacidic nitrating agents were developed that proved to be effective in secondary nitramine synthesis; 2,2-bis(chloromethyl)propane-1,3-diol dinitrate and 2- trifluoromethyl-2-propyl nitrate. These two nitrating reagents give nitramines in 60-100% yield without nitrosamine by-product formation. The reaction scope ... |
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Reports by Keyword(s)
NITROMETHANE
