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in subjects: "Electrostatics"  
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Use of Molecular Modeling to Determine the Interaction and Competition of Gases within Coal for Carbon Dioxide Sequestration

Description: A 3-dimensional coal structural model for the Argonne Premium Coal Pocahontas No. 3 has been generated. The model was constructed based on the wealth of structural information available in the literature with the enhancement that the structural diversity within the structure was represented implicitly (for the first time) based on image analysis of HRTEM in combination with LDMS data. The complex and large structural model (>10,000 carbon atoms) will serve as a basis for examining the intera… more
Date: February 23, 2003
Creator: Evanseck, Jeffrey D. & Madura, Jeffry D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Self-Consistent Simulation of Turbulence and Transport in Tokamak Edge Plasmas

Description: The status of coupling the fluid 3D turbulence code BOUT and the fluid plasma/neutral 2D transport code UEDGE is reported, where both codes simulate the edge region of diverted tokamaks from several cm inside the magnetic separatrix to the far scrape-off layer (SOL), thereby including the magnetic X-point. Because the characteristic time scale of the turbulence is short ({approx} 10{sup -5}-10{sup -4}s) and the profile evolution time scale can be long ({approx} 10{sup -2}-10{sup -1} s owing to … more
Date: September 3, 2003
Creator: Rognlien, T D; Umansky, M V; Xu, X Q & Cohen, R H
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A three-dimensional kinetic theory of continuous-beam stability

Description: This work is a three-dimensional stability study based on the modal analysis for a continuous beam of Kapchinskij-Vladimirskij (KV) distribution. The analysis is carried out self-consistently within the context of linearized Vlasov-Maxwell equations and electrostatic approximation. The emphasis is on investigating the coupling between longitudinal and transverse perturbations in the high-intensity region. The interaction between the transverse modes supported by the KV distribution and those mo… more
Date: January 1, 2003
Creator: Wang, T. F. (Tai-Sen F.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High current heavy ion beams in the electrostatic plasmalens

Description: We describe applications of the electrostatic plasma lens for manipulating and focusing moderate energy, high current, broad, heavy ion beams. Use of a plasma lens in this way has been successfully demonstrated in a series of experiments carried out collaboratively between IP NASU (Kiev) and LBNL (Berkeley) in recent years. Here we briefly review the plasma lens fundamentals, peculiarities of focusing heavy ion beams, and summarize some recent developments (experiments, computer simulations, th… more
Date: September 30, 2003
Creator: Goncharov, A.A. & Brown, I.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Semiannual Progress Report for Stimul-Responsive Polymers with Enhanced Efficiency in Reservoir Recovery Processes

Description: Acrylamide-based hydrophobically modified (HM) polybetaines containing N-butylphenylacrylamide (BPAM) and varying amounts of either sulfobetaine (3-(2-acrylamido-2-methylpropanedimethylammonio)-1-propanesulfonate, AMPDAPS) or carboxybetaine (4-(2-acrylamido-2-methylpropyldimethylammonio) butanoate, AMPDAB) comonomers were synthesized via micellar copolymerization. The terpolymers were characterized via {sup 13}C NMR and UV spectroscopies, classical and dynamic light scattering, and potentiometr… more
Date: February 28, 2003
Creator: McCormick, Charles & Hester, Roger
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In-situ characterization of colloidal soft solution processes.

Description: The purpose of this program was to investigate methods to characterize the colloidal stability of nanoparticles during the synthesis reaction, and to characterize their organization related to interparticle forces. Studies were attempted using Raman spectroscopy and ultrasonic attenuation to observe the nucleation and growth process with characterization of stability parameters such as the zeta potential. The application of the techniques available showed that the instrumentation requires high … more
Date: November 1, 2003
Creator: Tallant, David Robert; Rodriguez, Mark Andrew & Bell, Nelson Simmons
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Specimen charging on thin films with one conducting layer:Discussion of physical principles

Description: While the most familiar consequences of specimen charging in transmission electron microscopy can be eliminated by evaporating a thin conducting film (such as a carbon film) onto an insulating specimen, or by preparing samples directly on such a conducting film to begin with, a more subtle charging effect still remains. We argue here that specimen charging is in this case likely to produce a dipole sheet rather than a layer of positive charge at the surface of the specimen. A simple model of th… more
Date: April 15, 2003
Creator: Glaeser, Robert M. & Downing, Kenneth H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of an Electrostatic Dust Detector for use in a Tokamak Reactor

Description: Initial results from a novel device to detect dust particles settling on remote surfaces are presented. Dust particle inventories are a concern in next-step fusion devices. The increase in duty cycle will lead to a scale-up in the amount of particles generated by plasma material interactions. These particles will be chemically and radiologically hazardous and it will be important to establish that the in-vessel particle inventory is within regulatory limits. The detection device consists of two… more
Date: September 10, 2003
Creator: Bader, A.; Skinner, C. H.; Roquemore, A. L. & Langish, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Multigrid Particle-in-cell Simulations of Plasma Microturbulence

Description: A new scheme to accurately retain kinetic electron effects in particle-in-cell (PIC) simulations for the case of electrostatic drift waves is presented. The splitting scheme, which is based on exact separation between adiabatic and on adiabatic electron responses, is shown to yield more accurate linear growth rates than the standard df scheme. The linear and nonlinear elliptic problems that arise in the splitting scheme are solved using a multi-grid solver. The multi-grid particle-in-cell appro… more
Date: June 17, 2003
Creator: Lewandowski, J. L. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Electrostatic Discharge (ESD) Protection for a Laser Diode Ignited Actuator

Description: The use of laser diodes in devices to ignite pyrotechnics provides unique new capabilities including the elimination of electrostatic discharge (ESD) pulses entering the device. The Faraday cage formed by the construction of these devices removes the concern of inadvertent ignition of the energetic material. However, the laser diode itself can be damaged by ESD pulses, therefore, to enhance reliability, some protection of the laser diode is necessary. The development of the MC4612 Optical Actua… more
Date: June 1, 2003
Creator: SALAS, FREDERICK J.; SANCHEZ, DANIEL H. & WEINLEIN, JOHN HARVEY
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Electron Temperature Fluctuations and Cross-Field Heat Transport in the Edge of Diii-D

Description: OAK-B135 The fluctuating E x B velocity due to electrostatic turbulence is widely accepted as a major contributor to the anomalous cross-field transport of particles and heat in the tokamak edge and scrape-off layer (SOL) plasmas. This has been confirmed by direct measurements of the turbulent E x B transport in a number of experiments. Correlated fluctuations of the plasma radial velocity v{sub r}, density n, and temperature T{sub e} result in time-average fluxes of particles and heat given by… more
Date: July 1, 2003
Creator: Rudakov, D. L.; Boedo, J. A.; Moyer, R. A.; Kraseninnikov, S.; Mahdavi, M. A.; McKee, G. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Barrier to Trap Filling CuIn1-xGaxSe2: Preprint

Description: Voltage pulses of variable length were applied to CuIn1-xGaxSe2/CdS (0< x< 1) junction solar cells. The resulting transient capacitance emission signal was recorded for several minutes. The amplitude of the capacitance emission signal increased linearly with the log of pulse time. These data do not follow the standard model for trap capture and emission of carriers. Instead they follow a simple electrostatic model based on electrostatic charging of traps.
Date: April 1, 2003
Creator: Young, D. L.; Ramanathan, K.; Contreras, M.; Abushama, J. & Crandall, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

THE AGS ELECTROSTATIC SEPTUM.

Description: The previous slow beam extraction electro static septum in the AGS was designed in 1981. Research documented at the Fermi Laboratory was used as the base line for this design. The septum consisted of a ground plane of .002 inch diameter wire tungsten-rhenium alloy (75%W 25%Re) with a hollow welded titanium cathode assembly. The vacuum chamber is stationary and the septum is moved with a pair of high vacuum linear feed throughs. After years of beam time, the frequency of failures increased. The … more
Date: May 12, 2003
Creator: HOCK,J. RUSSO,T. GLEN,J. BROWN,K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Mesoscopic Fluctuations in the Distribution of Electronic Defects Near the Surface Layer of Cu(In,Ga)Se2

Description: High-resolution cathodoluminescence spectroscopic imaging (CLSI) has been employed to study the radiative recombination processes in Cu(In,Ga)Se2 (CIGS) films used in solar cells. Mesoscopic fluctuations of the electrostatic potential explain the observed behavior for the radiative transitions identified in the emission spectrum. We show evidence for passivation of grain boundaries near the surface layers of these films. In addition, our results suggest different point defect physics for the su… more
Date: May 1, 2003
Creator: Romero, M. J.; Ramanathan, K.; Contreras, M. A.; Al-Jassim, M. M.; AbuShama, J. & Noufi, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

On the transition rates of the Fe X and Fe XIV corona lines

Description: Despite a considerable scatter of the theoretical predictions of the M1/E2 transition rate of the ''red iron line'' (FeX) in the solar corona, there is disagreement of all the results with the single measurement that used an electrostatic ion trap. Employing a heavy-ion storage ring for measuring the same transition in isoelectronic ions of Co, Ni, and Cu, the situation has been clarified, and a new data point for FeX can be determined by extrapolation. This result agrees with the basic atomic … more
Date: November 20, 2003
Creator: Trabert, E
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chaos and collective relaxation in galaxies and charged-particle beams

Description: Both galaxies and charged particle beams can exhibit collective relaxation on surprisingly short time scales. This can be attributed to the effects of chaos, often triggered by resonances caused by time-dependences in the bulk potential, which act almost identically for attractive gravitational and repulsive electrostatic forces. These similarities suggest that many physical processes at work in galaxies, albeit not subject to direct controlled experiments, can be tested indirectly using facili… more
Date: January 1, 2003
Creator: Bohn, Courtlandt; U., /Fermilab /Northern Illinois; Kandrup, Henry E.; U., /Florida; Kishek, Rami A.; O'Shea, Patrick G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Particle-in-cell simulations of the high current experiment

Description: The particle-in-cell code WARP has been used to simulate beam dynamics for the intense ion beam of the High Current Experiment. First a study was done of the dynamic aperture of the alternating-gradient electrostatic quadrupole lattice of the experiment, including nonlinearity due to image forces and imperfections of the focusing lattice field. It was found that particle loss, rather than emittance growth, determined the usable aperture. Simulations of transport in the High Current Experiment w… more
Date: May 1, 2003
Creator: Celata, C. M.; Bieniosek, F. M.; Prost, L.; Seidl, P. A.; Friedman, A. & Grote, D. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electromagnetic Weibel Instability in Intense Charged Particle Beams with Large Energy Anisotropy

Description: In plasmas with strongly anisotropic distribution functions, collective instabilities may develop if there is sufficient coupling between the transverse and longitudinal degrees of freedom. Our previous numerical and theoretical studies of intense charged particle beams with large temperature anisotropy [E. A. Startsev, R. C. Davidson and H. Qin, PRSTAB, 6, 084401 (2003); Phys. Plasmas 9, 3138 (2002)] demonstrated that a fast, electrostatic, Harris-like instability develops, and saturates nonli… more
Date: October 20, 2003
Creator: Startsev, Edward A. & Davidson, Ronald C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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