| Optical Measurements of Air Plasma |
05 MAY 2008 |
28 pages |
| Authors:
Robert J. Vidmar; NEVADA UNIV BOARD OF REGENTS RENO OFFICE OF SPONSORED RESEARCH
|
 | Electron-beam impact ionization of air was studied in the context of optical diagnostics. The electron beam originates in a pulsed 100 keV 20-mA source and propagated through a 1/2 - mil aluminum transmission window into a 400-liter test cell. Plasma production in air was investigated over the pressure range of 636 Torr to 1 mTorr with pulse durations from 1 ms to 10 ms. Microwave diagnostics were used to quantify ... |
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| ERR Gamma: Does an Orphan Nuclear Receptor Link Steroid Hormone Biogenesis to Endocrine Resistance? |
01 SEP 2007 |
39 pages |
| Authors:
Rebecca B. Riggins; GEORGETOWN UNIV WASHINGTON DC
|
| Estrogen-related receptor gamma (ERR gamma) is an orphan nuclear receptor with structural similarities to ER alpha and ER beta (1). In addition to its ability to transactivate classical and imperfect estrogen response elements (EREs) ERR gamma is a potent activator of transcription from steroidogenic factor-1 (SF-1) response elements (SF-1REs). Many genes regulated by SF-1REs control key aspects of cholesterol and fatty acid synthesis important not only for generation of the ... |
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| Plasma-Arc Deposited Elemental Boron Film for use as a Durable Nonstick Coating |
SEP 2007 |
27 pages |
| Authors:
C. C. Klepper; HY-TECH RESEARCH CORP RADFORD VA
|
| Report developed under Small Business Innovation Research Contract. Under this Phase I SBIR contract, HY-Tech Research performed development of an abrasion resistant, non-stick coating for cookware used by the U.S. Army in the field. The deposition technique uses a vacuum arc source of elemental boron, a high-temperature material with excellent hardness, lubricity and chemical inertness. HY-Tech's boron arc source is based on the vacuum (cathodic) arc process, which produces the ... |
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| Modeling of Hall Thruster Lifetime and Erosion Mechanisms (Preprint) |
SEP 2007 |
27 pages |
| Authors:
Shannon Y. Cheng; Manuel Martinez-Sanchez; MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| An axisymmetric hybrid-PIC model of the Hall thruster plasma discharge has been upgraded to simulate the erosion of the thruster acceleration channel, the degradation of which is the main life-limiting factor of the propulsion system. Evolution of the thruster geometry as a result of material removal due to sputtering is modeled by calculating wall erosion rates, stepping the grid boundary by a chosen time step and altering the computational mesh ... |
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| Controlled Precipitation of Radiation Belt Particles |
23 AUG 2007 |
18 pages |
| Authors:
Umran S. Inan; Timothy F. Bell; Timothy W. Chevalier; STANFORD UNIV CA SPACE TELECOMMUNICATIONS AND RADIOSCIENCE LAB (STAR)
|
| The overall objectives of this work are to: * Quantify the requirements for controlled precipitation of radiation belt particles in order to mitigate space particle effects * Address the issue of coupling of space based antennas to the surrounding magnetoplasma for use in system design * Determine radiated power from single transmitting element The completion of these goals requires the design of antenna-in-plasma codes which simulate the interaction of radiating ... |
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| Analytical Extraction of Plasma Properties Using a Hall Thruster Efficiency Architecture (Preprint) |
22 AUG 2007 |
15 pages |
| Authors:
Daniel L. Brown; C. W. Larson; James M. Hass; Alec D. Gallimore; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACECRAFT PROPULSION BRANCH
|
| An investigation of the conversion from anode electrical energy to jet kinetic energy in a laboratory model Hall thruster test-bed yielded an experimentally determined thrust efficiency based on the product of propellant, voltage, and current utilization. This method accounts for the effects of the ion velocity distribution function (VDF), electron recycle fraction, plume divergence, and the fractional loss of acceleration voltage within the discharge chamber. The architecture of the efficiency ... |
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| Negative Thermal Expansion In Ultrathin Plasma Polymerized Films (Preprint) |
MAR 2007 |
15 pages |
| Authors:
Timothy J. Bunning; Hao Jiang; Srikanth Singamaneni; Vladimir V. Tsukruk; Melburne C. LeMieux; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| Owing to the increasing applications of polymer films with nanoscale thickness, it is imperative to fully characterize the physical properties in these films, which could be significantly different from the bulk properties due to the surface and interfacial effects. Interactions with the substrate and high specific surface area (film/ air and film/ substrate) can cause peculiar properties of the ultrathin polymer films. In a recent study the glass transition of ... |
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| Seeking Radio Emissions from Hypervelocity Micrometeoroid Impacts: Early Experimental Results from the Ground |
15 NOV 2006 |
8 pages |
| Authors:
M. J. Starks; D. L. Cooke; B. K. Dichter; L. C. Chhabildas; W. D. Reinhart; III Thornhill T. F.; AIR FORCE RESEARCH LAB HANSCOM AFB MA
|
| High-velocity impact experiments have been conducted to look for radio frequency (RF) emissions from impact-produced plasmas that could be used to identify micrometeoroid impacts to spacecraft in orbit. Launched by a three-stage light gas gun, 17 mm diameter by 0.9 mm thick Ti6Al-4V flyer plates impacted 0.75 mm thick indium (In) foil at more than 10 km s(-1). The resulting collision presumably ionized some fraction of the vaporized in cloud, ... |
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| Laser Initiation and Radiofrequency Sustainment of Seeded Air Plasmas |
APR 2006 |
49 pages |
| Authors:
J. E. Scharer; WISCONSIN UNIV-MADISON DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
|
| We have carried out research on high density [10(exp 11) - 4 x 10(exp 13)], large volume (500-2500 cc), high-pressure (20-760 Torr), laser initiated plasma produced in nitrogen, argon and air. The low ionization energy organic gas (TMAE) laser-initiated see plasmas create an initial condition that is used for plasma sustainment at much lower radiofrequency (RF) power levels (0.4 - 3 W/cc) than is the case for RF initiation alone. ... |
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| A Study of Collapse Events in Ultraviolet Light Filaments Due to Transient Edge Effects |
MAR 2006 |
110 pages |
| Authors:
Paul L. Muller; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT/DEPT OF ENGINEERING PHYSICS
|
| Intense, short light pulses can form filaments capable of propagating kilometers through the atmosphere. This is due to the nonlinear index of refraction of the atmosphere in response to the pulse's high intensity, which creates a self-focusing effect that further intensifies the pulse. This focusing is balanced by the formation of defocusing plasma by the pulse. A split-step propagation model was used to simulate the propagation of these pulses through ... |
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| An Investigation of Bremsstrahlung Reflection in a Dense Plasma Focus Device |
MAR 2006 |
54 pages |
| Authors:
Robert Thomas; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
|
| An overview of Bremsstrahlung radiation, which is prevalent in high-temperature fusion plasmas, is given, as well as estimates for the power and energy flux to a reflector wall from a dense plasma focus device burning p-11B. From these calculations, the wall temperature and ablation rate can be calculated. The physics derived from Inertial Confinement Fusion (ICF) Hohlraum use are applicable in the case where the wall temperature exceeds 105 K, ... |
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| Macroscopic Computational Model of Dielectric Barrier Discharge Plasma Actuators |
FEB 2006 |
162 pages |
| Authors:
Timothy R. Klein; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT/DEPT OF ENGINEERING PHYSICS
|
| Recent progress in the generation and sustainment of gas discharges at atmospheric pressure has energized research in the field of plasma-aerodynamics. Plasma actuators are promising devices that achieve flow control with no moving parts, do not alter the airfoil shape and place no parts in the flow. The operation of a plasma actuator is examined using a macroscopic (force and power addition) computational fluid dynamic model of a dielectric barrier ... |
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| Fast Surface Temperature Measurement of Teflon Propellant in Pulsed Ablative Discharges Using HgCdTe Photovoltaic Cells (PREPRINT) |
2006 |
39 pages |
| Authors:
Erik L. Antonsen; Rodney L. Burton; Garrett A. Reed; Gregory G. Spanjers; ILLINOIS UNIV AT URBANA
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| High speed Mercury Cadmium Telluride photovoltaic detectors sensitive to infrared emission are investigated as a means of measuring real-time surface temperature on a micro-second timeframe pulsed ablative discharge with Teflon(TradeMark) as the ablated material. Analysis is used to derive a governing equation for detector output voltage for materials with wavelength dependent emissivity. The detector output voltage is experimentally calibrated against thermocouples embedded in heated Teflon. Experimental calibration is performed with ... |
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| Development of a Unified Code for Nonequilibrium Plasma Systems |
31 DEC 2005 |
22 pages |
| Authors:
Iain D. Boyd; MICHIGAN UNIV ANN ARBOR DEPT OF AEROSPACE ENGINEERING
|
| The goal of the project was to develop a new computational code to be used at the Arnold Engineering Development Center, (AEDC), Tullahoma, Tennessee, for analysis of plasmas characterized by high ionization fractions and extremely low number densities. Such conditions arise in two particular test facilities operated at AEDC: (1) the Decade Radiation Test Facility (DRTF), used to test the effects of strong radiation sources on materials and spacecraft components; ... |
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| Collision Dynamics of Rydberg Atoms and Molecules at Ultralow Energies |
31 DEC 2005 |
108 pages |
| Authors:
M. R. Flannery; GEORGIA INST OF TECH ATLANTA SCHOOL OF PHYSICS
|
| First Major Highlight: Collisional Stark Mixing at ultralow energies in Rydberg Plasmas. Atoms in high (n,l) states formed in cold Rydberg plasmas decay to the ground state in a succession of radiative transitions populating intermediate excited states. Which states are populated during cascading and with what probability can be obtained from known transition probabilities. Classical models simplify the calculation considerably, revealing the "trajectory" in nt space followed during the cascade, ... |
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| Excitation of the Magnetospheric Cavity by Space-Based ELF/VLF Transmitters |
30 DEC 2005 |
11 pages |
| Authors:
Timothy F. Bell; STANFORD UNIV CA SPACE TELECOMMUNICATIONS AND RADIOSCIENCE LAB (STAR)
|
| During the period of performance, Stanford University completed the development of integral equations describing the distribution of current along a dipole antenna radiating ELF/VLF waves in the magnetospheric cavity. It was found that the radiation resistance was much smaller near the lower-hybrid resonance frequency than previously believed. Stanford University included the effects of ion temperature in the plasma dielectric tensor. It was found that the ion temperature had a first-order ... |
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| The Role of Dynamic in the Regulation of Signaling by the erbB Family of Receptor Tyrosine Kinases |
14 SEP 2005 |
14 pages |
| Authors:
Megan C. King; Mark Lemmon; PENNSYLVANIA UNIV PHILADELPHIA
|
| Improper regulation of the level and duration of activated erbB family growth factor receptors at the cell surface can lead to uncontrolled cell proliferation and transformation via over-stimulation of mitogenic signaling cascades. The large GTPase dynamin is a key regulator both of transport of receptors to the plasma membrane after receptor biosynthesis and down-regulation of receptors via receptor-mediated endocytosis (RME), during which it is involved in the scission of endocytic ... |
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| Evaluation and Selection of an Efficient Fuel/Air Initiation Strategy for Pulse Detonation Engines |
SEP 2005 |
71 pages |
| Authors:
Brent T. Channell; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Rapid and efficient initiation of hydrocarbon/air mixtures has been identified as one of the critical and enabling technologies for Pulse Detonation Engines (PDEs). Although the NPS Rocket Propulsion Laboratory has successfully demonstrated fuel/air detonations in a valveless pulse detonation engine using ethylene, propane, and JP-10 fuels, past engine designs have relied upon a sensitive fuel/oxygen initiator unit. To realize the increased thermodynamic efficiencies of PDEs and thus compete with ramjets ... |
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| Optical Imaging Provides a Clear Picture of Ionospheric Disturbances |
15 AUG 2005 |
9 pages |
| Authors:
R. Esposito; T. Pedersen; AIR FORCE RESEARCH LAB HANSCOM AFB MA
|
| During daylight hours, ultraviolet light from the sun ionizes the neutral gas of the earth's upper atmosphere (70-1500 km altitude), creating a partially ionized plasma. This plasma then gradually decays throughout the night. The atmospheric region associated with this phenomenon is called the ionosphere, and this zone is of great practical importance to the Department of Defense and civilian industries because of its effect on radio waves. Depending on the ... |
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| Modification of Aerodynamic Surfaces Using Plasma |
JUL 2005 |
111 pages |
| Authors:
Igor M. Minaev; MOSCOW STATE UNIV (RUSSIA)
|
| This report results from a contract tasking M.V. Lomonosov Moscow State University (MSU) as follows: The contractor will accomplish the following: (1) develop and manufacture a compact plasma generator; (2) manufacture various geometric shaped wind tunnel models; (3) investigate the propagation of electric fields and discharges over the models; (4) conduct aerodynamic wind tunnel testing; (5) investigate the effect of the plasma on aerodynamic performance and assess sensitivities to plasma ... |
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| Collision Physics in Atmospheric Pressure Non-Equilibrium Plasmas |
JUN 2005 |
4 pages |
| Authors:
Alfred Z. Msezane; CLARK ATLANTA UNIV GA DEPT OF PHYSICS
|
| Recently, a new aspect of interchannel coupling has been found 1, known as spin-orbit activated interchannel coupling, stimulated by an experimental study on photoionization of Xe in the vicinity of the 3d threshold. This effect results only through the spin-orbit splitting of inner-shell thresholds. Effects of spin-orbit activated interchannel coupling on nondipole 2 photoelectron angular distribution asymmetry parameters have been discussed, including the spin-polarization of photoelectrons from 3d electrons of ... |
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| Absolutely Calibrated Vacuum Ultraviolet Spectra in the 150 nm to 250 nm Range from Plasmas Generated by the NIKE KrF Laser |
25 MAR 2005 |
31 pages |
| Authors:
J. F. Seely; Uri Feldman; G. E. Holland; J. L. Weaver; A. N. Mostovych; S. P. Obenschain; A. J. Schmitt; R. Lehmberg; Benjawan Kjornarattanawanich; C. A. Back; NAVAL RESEARCH LAB WASHINGTON DC SPACE SCIENCE DIV
|
| High resolution vacuum ultraviolet (VUV) spectra were recorded from plasmas generated by the NIKE KrF laser for the purpose of observing emission from the two-plasmon decay instability (TPDI) at 2/3 the NIKE wavelength (165 nm). The targets were irradiated by up to 43 overlapping beams with intensity up to ≈1014 W/sq cm and with beam smoothing by induced spatial incoherence (ISI). The targets consisted of planar foils of CH, BN, ... |
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| COLISEUM: An Application Programming Interface for 3D Plasma Simulations |
20 DEC 2004 |
19 pages |
| Authors:
Douglas VanGilder; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
|
| APPROACH: A new 3D plasma simulation system (COLISEUM) is being developed: * Allows easy implementation of various plasma simulation modules for quicker code development & controllable fidelity * Using COTS extensively. CURRENT STATUS: * Low-fidelity plume (prescribed plume & ray tracing) * High- fidelity plume (AQUILA & DRACO) * Thruster modeling (HET & Colloid). FUTURE WORK: * DRACO (charging, sputtering, surface contamination) * AQUILA (parallel, generalized collisions) * Device modeling ... |
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| Investigation of Ion Beam Neutralization Processes With 2-D and 3-D PIC Simulations |
DEC 2004 |
10 pages |
| Authors:
Adrian Wheelock; David L. Cooke; Nicholas A. Gatsonis; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| While it is common knowledge that ion beams are easily neutralized for both current and charge density using a variety of means, the precise process of neutralization remains unknown. With the increasing importance of electric propulsion, and in particular micropropulsion systems, this question is of significant importance. Additionally, it has bearing on thruster design, space instrument calibration, electrodynamic tethers, and ionospheric research. A review of the present state of knowledge ... |
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| Relationship Between Mammographic Density and IGF Levels Among Hispanic and Non-Hispanic White Women |
AUG 2004 |
5 pages |
| Authors:
Leslie Arendell; Zhao Chen; ARIZONA UNIV TUCSON
|
| The purpose of this study is to use information collected from the parent study, the Women's Breast and Bone Density study (WBBD)to investigate the relationship between breast density and IGF levels in pre and postmenopausal Hispanic and non-Hispanic White women. The parent study was completed by the May 31, 2003. In all, recruitment was a lower than expected for the Hispanic women, but all recruitment goals were either met or ... |
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| The Response of Propellants to Plasma Radiation |
JUN 2004 |
27 pages |
| Authors:
Richard A. Beyer; Rose A. Pesce-Rodriquez; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Experiments have been done where standard and research propellants were exposed to the visible and infrared (IR) light from a high-energy plasma discharge. Measurements of mass lost by the sample. analysis of the IR spectra of evolved gases. and optical microscopy have been used to characterize the response. In addition. the response for graphite-free JA2 conditioned to hot and cold temperatures has shown that the magnitude of the response for ... |
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| Heterodyne Interferometer for Triggering Gas-Puff PRSs |
25 MAY 2004 |
33 pages |
| Authors:
Robert C. Hazelton; HY-TECH RESEARCH CORP RADFORD VA
|
| Consistent timing between the injection of gas in plasma radiation sources (PRSs) and the generator current pulse is crucial to producing high- yield x-ray pulses. This Phase 1 SBIR effort has shown that triggering modes currently used in DTRA's x-ray simulator program (high voltage trigger pin; command fire mode) introduce an effective variation in initial load mass of +/- 11%, and this may be as high as +/-20%. This variation ... |
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| Temporally Resolved Langmuir Probe Measurements in LAPPS |
12 APR 2004 |
28 pages |
| Authors:
Darrin Leonhardt; WIlliam Amatucci; George Gatling; NAVAL RESEARCH LAB WASHINGTON DC
|
| Electron beams efficiently ionize and dissociate gas, to form low temperature (<1.5 eV) high-density (1O(to the 10)-lO(to the 12)cm(to the -3) plasmas with low internal fields. These plasma sources have culminated in LAPPS, NRL's Large Area Plasma Processing System for surface modification of materials. Single Langmuir probes were constructed and used to determine global plasma parameters (electron temperature, density, and plasma potential) in modulated plasmas generated by high-energy (2 keV) ... |
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| MHD Turbulence at Moderate Magnetic Raynolds Number |
24 MAR 2004 |
12 pages |
| Authors:
B. Knaepen; S. Kassinos; D. Carati; UNIVERSITE LIBRE DE BRUXELLES (BELGIUM)STATISTICAL AND PLASMA PHYSICS
|
| Magnetohydrodynamics applies to many conductive fluid and plasma flows encountered in nature and in industrial applications. In numerous circumstances, the flow is subject to a strong mean magnetic field. This happens in the earth's liquid core and is ubiquitous in solar physics for topics like sunspots, solar flares, solar corona, solar wind etc. Mean magnetic fields play an important role on even larger scales, for instance in the dynamics of ... |
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| Optimization of Off-Axis ICOS and Applications to Flow Tube Kinetics |
31 DEC 2003 |
12 pages |
| Authors:
Manish Gupta; Anthony O'Keefe; LOS GATOS RESEARCH MOUNTAIN VIEW CA
|
| In this AFOSR granting period, Los Gatos Research explored the capabilities of Off-Axis Integrated Cavity Output Spectroscopy (Off-Axis ICOS) with an especial emphasis towards flow-tube kinetics studies. Specifically, search was performed to ascertain the application of Off-Axis ICOS to spatial imaging, time-dependant phenomenon, and through-plasma spectroscopy. Achievements included developing a theoretical framework to simulate spot pattern images in the presence of spatially-inhomogeneous cavity loss, simulating the time-dependent cavity transmission for ... |
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| Physical Methods For Inactivating Spores: A Critical Assessment |
19 NOV 2003 |
8 pages |
| Authors:
Glenn E. Spangler; Peter Setlow; Barbara Setlow; TECHNISPAN LLC PIKESVILLE MD
|
| A significant literature has developed around the application of physical techniques to the inactivation of spores. These include pulsed high electric fields, plasma sterilization, and supercritical fluid extraction, in addition to the more traditional autoclaving technique. Pulsed high electric fields electroporate protective membranes, plasma sterilizers generate very reactive species, and supercritical fluids extract biologically significant compounds. Not all these techniques work as described, however. The cortex interferes with electroporation by ... |
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| Monitoring Sulfur Mustard Exposure by the GC-MS Analysis of Thiodiglycol Cleaved from Blood Proteins |
18 NOV 2003 |
8 pages |
| Authors:
William D. Korte; J. R. Smith; Benedict R. Capacio; Michael DeLion; Dana R. Anderson; ARMY MEDICAL RESEARCH INST OF CHEMICAL DEFENSE ABERDEEN PROVING GROUND MD
|
| A GC-MS assay of thiodiglycol (TDG) released from blood protein adducts of sulfur mustard (SM) was developed. Exposure of pig blood to SM (24 nM to 400 nM) resulted in a SM concentration-dependent increase in plasma TDG levels from 2.0 pg/mg protein to 38 pg/mg protein. TDG levels in blood samples drawn from monkeys (Chlorocebus aethiops) after a 1.0 mg/kg intravenous SM injection decreased from 220 pg/mg to 10 pg/mg ... |
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| Thermochemical Processes in Plasma Aerodynamics (CD-ROM) |
20 OCT 2003 |
|
| Authors:
A. A. Turchak; A. V. Korabelnikov; A. L. Kuranov; Silvano Casini; V. K. Vasilyev; LENINETZ HOLDING CO NIPGS SAINT PETERSBURG (RUSSIA) HYPERSONIC SYSTEM RESEARCH INST
|
 | ELECTRONIC FILE CHARACTERISTICS: 10 files; Adobe Acrobat (.PDF) and MS Word (.DOC). PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 19.9 MB. SYSTEMS DETAIL NOTE: ABSTRACT: The Final Proceedings for Thermochemical Processes in Plasma Aerodynamics, 28-31 July 2003. This is an interdisciplinary conference. Topics to be covered include 1) Active thermal protection on the basis of endothermic reactions; 2) The problem of catalysis at the conversion of hydrocarbon fuel; 3) Burning ... |
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| Estimation of Parameters of Plasma on the Data on Shock Wave Passage Through Plasma |
OCT 2003 |
5 pages |
| Authors:
V. V. Kuchinsky; V. J. Goljatin; HYPERSONIC SYSTEMS RESEARCH INST SAINT PETERSBURG (RUSSIA)
|
| The report is devoted to an opportunity of use of measurement results of various shock waves parameters for an estimation of parameters of plasma through which the shock wave is distributed. The purpose of the report is discussion of various experimental situations in which the data of the measurements which have been carried out by different methods, will allow to make representation about a condition of plasma (or spatial heterogeneity ... |
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| RF Discharge at Medium and High Pressure and Its Possibilities for Material Surface Modification |
OCT 2003 |
|
| Authors:
A. F. Alexandrov; G. E. Bugrov; E. A. Kralkina; V. B. Pavlov; V. Plaksin; V. P. Savinov; V. Yu. Sergeenko; I. B. Timofeev; K. V. Vavilin; MOSCOW STATE UNIV (RUSSIA) DEPT OF PHYSICS
|
| During last years the tendency became evident to develop and utilize discharge at medium and high pressure in industry especially for plasma chemical applications and surface modification of materials. The review of the literature 1 devoted to this subjects, on the one hand specifies wide opportunities of such discharges and on the other hand demonstrates absence of detailed understanding of physical processes mechanisms in medium and high pressure discharges as ... |
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| Combined Non-Self-Maintained Discharge in Air for Generating of Chemically Active Particles |
OCT 2003 |
8 pages |
| Authors:
N. V. Ardelyan; V. L. Bychkov; O. A. Gordeev; A. I. Klimov; MOSCOW STATE UNIV (RUSSIA)
|
| Development of plasma technologies for problems of external and internal gas dynamics is impossible without the detailed studies of different discharge types both self maintained and non-self maintained improvement. These questions were discussed in many scientific forums recently. In particular, the longitudinal and transversal gas discharges in air were studied in air flows 1- 3 for their applications in applied problems of external and internal aerodynamics (ignition of flammable mixtures ... |
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| Plasma Antennas: Survey of Techniques and Current State of the Art |
29 SEP 2003 |
32 pages |
| Authors:
David C. Jenn; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Plasma antennas refer to a wide variety of antenna concepts that incorporate some use of an ionized medium. This study summarizes the basic theory behind the operation of plasma antennas based on a survey of patents and technical publications. Methods of exciting and confining plasmas are discussed, and the current state of the art in plasma technology is examined. |
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| Analysis of Gases Produced by Three Underwater Cutting Devices |
JUL 2003 |
9 pages |
| Authors:
R. S. Lillo; J. M. Caldwell; NAVY EXPERIMENTAL DIVING UNIT PANAMA CITY FL
|
| The gas produced during underwater testing of 3 cutting systems was collected and analyzed to assess the explosion hazard related to the 3 processes. The underwater plasma cutting system produced up to 6% H2, while the UK cutting rod produced up to 95% H2. As the lower flammable/explosive limits of H2 in air are 4%, H2 safety issues are potentially related to using both these cutting processes. However, the explosive ... |
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| Ion Energy Diagnostics in the Far-Field Plume of a High-Specific Impulse Hall Thruster |
30 JUN 2003 |
13 pages |
| Authors:
Richard R. Hofer; James M. Haas; Alec D. Gallimore; AIR FORCE RESEARCH LAB EDWARDS AFB CA
|
| Retarding potential analyzer and cylindrical Langmuir probe measurements were taken on the laboratory model NASA-173Mv2 to improve understanding of the physical processes affecting Hall thruster performance at high specific impulse. A retarding potential analyzer was used to measure the ion voltage distribution at voltages of 300-800 V. A cylindrical Langmuir probe was also used to obtain the local plasma potential so that the true ion voltage was obtained. The goal ... |
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| Polymers Used as Fuel for Laser Plasma Thrusters in Small Satellites |
30 APR 2003 |
50 pages |
| Authors:
Thomas Lippert; PAUL SCHERRER INST VILLIGEN (SWITZERLAND)
|
| This report results from a contract tasking Paul Scherrer Institut as follows: The contractor will investigate those properties of promising polymers which influence the performance of Laser Plasma Thrusters LPTs). Preliminary data show that the properties of the ablated polymer have a strong effect on the achievable specific impulse. Among the issues to be investigated are choice of substrate and adhesion of the polymer to the substrate influence of dopants ... |
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| 29TH IEEE International Conference on Plasma Science |
01 SEP 2002 |
|
| Authors:
Robert Fedosejevs; INSTITUTE OF ELECTRICAL AND ELECTRONICSENGINEERS INC PISCATAWAY NJ
|
| The 29th IEEE Conference on Plasma Science was held in Banff, Alberta, Canada from May 26-30, 2002. A total of 440 abstracts were submitted for Plenary, invited, oral and poster presentations which are included in the Conference Record Book. The presentations covered all major areas of Plasma Science including partially ionized plasmas, space plasmas, microwave devices, Z-pinches, magnetic fusion, laser-produced plasmas, flat panel displays, Plasma processing, medical and biological applications, ... |
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| Studies of Electron-Ion Interactions Using the CRYRING Heavy-Ion Storage Ring Facility |
AUG 2002 |
12 pages |
| Authors:
Mats Larsson; STOCKHOLM UNIV (SWEDEN)
|
| This report results from a contract tasking Stockholm University as follows: CRYRING, a synchrotron/heavy-ion storage ring facility, has proved to be a powerful tool for measurements of branching ratios in recombination of polyatomic molecular ions. However, there are important questions that still need to be addressed for organic ions such as: 1)Is there a mass limit at which fragmentation decreases or even vanishes and most or all of the electron ... |
|
| International Workshop Thermochemical and Plasma Processes in Aerodynamics, Held in Saint-Petersburg, 15-19 July, 2002 |
19 JUL 2002 |
195 pages |
| Authors:
LENINETZ HOLDING CO NIPGS SAINT PETERSBURG (RUSSIA) HYPERSONIC SYSTEM RESEARCH INST
|
| The Final Proceedings for Thermochemical Processes in Plasma Aerodynamics, 15 July 2002 - 18 July 2002 This is an interdisciplinary conference. Topics to be covered include 1) Active thermal protection on the basis of endothermic reactions; 2) The problem of catalysis at the conversion of hydrocarbon fuel; 3) Burning of a modified hydrocarbon fuel; 4) Non-equilibrium kinetics with hydrocarbon components participation; 5) Plasma aerodynamics of flows. |
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| Algorithm Development for the Two-Fluid Plasma Model |
13 MAY 2002 |
24 pages |
| Authors:
Uri Shumlak; UNIV OF WASHINGTON SEATTLE DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| A preliminary algorithm based on the two-fluid plasma model is developed to investigate the possibility of simulating plasmas with a more physically accurate model than the MHD (magnetohydrodynamic) model. The algorithm is based on a Roe-type approximate Riemann Solver. Beginning with the two-fluid plasma model, the governing equations are normalized and formulated in conservation form. The eigenvalues and eigenvectors of the system flux Jacobians are determined and properly normalized to ... |
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| Synthesis of Biocompatible Surfaces by Different Techniques |
APR 2002 |
|
| Authors:
E. Garreta; T. Fernandez; S. Borros; J. Esteve; C. Colominas; BARCELONA UNIV (SPAIN)
|
| IN THE PRESENT WORK, A SOL-GEL METHOD OF HA synthesis has been developed using different calcium and phosphorous precursors. In order to make a porous scaffold, HA aerogel formation and HA liofilization processes have been studied. The liofilized HA and the MA aerogels have been characterized by SEM-EDX and X-Ray diffraction. Finally, so as to improve the biocompatibility and the bioadhesion of the MA scaffolds, different plasma polymerization techniques have ... |
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| Antimicrobial Coatings Obtained in an Atmospheric Pressure Dielectric Barrier Glow Discharge |
APR 2002 |
|
| Authors:
Sabine Paulussen; Dirk Vangeneugden; Oliver Goossens; Erik Dekempeneer; FLEMISH INST FOR TECHNOLOGICAL RESEARCH(VITO) MOL (BELGIUM)
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| This paper addresses the development of plasma polymer coatings that should prevent bacteria from adhering to medical devices, implants, textile fibers, packaging materials, etc. The two main parameters affecting bacterial colonization onto surfaces are the surface energy and the surface roughness. Both parameters can be adjusted by the deposition of a thin plasma polymer coating in an atmospheric pressure dielectric barrier glow discharge. According to SEM, FTIR, SPM, XPS and ... |
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| Initiation of Chemical Reactions in Energetic Materials Using Plasmas and Arc Channels |
29 MAR 2002 |
35 pages |
| Authors:
Mohamed A. Bourham; NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF NUCLEAR ENGINEERING
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| Experiments were conducted to determine the spatial and temporal distribution of the plasma temperature, pressure, number density, and velocity in the plasma-flow-field of an electrothermal source. The experiments revealed a decreasing plasma pressure, plasma temperature and plasma number density as plasma is leaving the capillary source and expands in air. The plasma jet velocity 2 inches from the source exit was found to be about 1300 m/s. Following plasma flow-field ... |
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| Positron Plasmas in the Laboratory |
20 MAR 2002 |
6 pages |
| Authors:
Clifford M. Surko; CALIFORNIA UNIV SAN DIEGO LA JOLLA
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| This grant supported work to develop efficient methods to accumulate low-energy positrons in the laboratory and to use the resulting positron plasmas for a range of scientific and technological applications. Techniques for trapping and manipulating positrons were refined and expanded. A new generation of positron accumulator was designed and built. It functions up to specifications, confining 3 x 10(exp 8) positrons at densities >- 10(exp 7)/cu cm. A new technique ... |
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| Investigation of Non-Equilibrium Plasmas |
06 MAR 2002 |
416 pages |
| Authors:
Clark W. Hawk; ALABAMA UNIV IN HUNTSVILLE
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| The research program investigated non-equilibrium plasmas with a variety of simple gases for the purpose of obtaining experimental data that can be used to anchor analytical models of flowing plasmas suitable for various electric propulsion devices. A microwave plasma generator(MPG) operating. at .2. 45GHz and 3kW was the initial source of the plasmas. The working fluids included: argon, helium, nitrogen, carbon dioxide, and water vapor. The research also included investigation ... |
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| Prostate Cancer in Nigerians, Jamaicans and U.S. Blacks |
MAR 2002 |
10 pages |
| Authors:
Vincent L. Freeman; LOYOLA UNIV MAYWOOD IL
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| This research attempts to develop the infrastructure for comparative studies of prostate cancer involving West Africa, the Caribbean and the United States. Six essential areas are addressed: case recruitment, case characterization, tissue collection and storage, integrated database development, targeted laboratory expertise and pilot research. Key Research Accomplishment During Year 1: (1) changed title of project to "Prostate Cancer in Nigerians, Jamaicans and U.S. Blacks"; (2) maintained the centralized data repository ... |
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Reports by Keyword(s)
PLASMAS(PHYSICS)
