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Nonlinear ion-cyclotron waves in mirror machines. Paper IAEA-CN-38/S-1

Description: Experimental results on ion-cyclotron waves observed in the 2XIIB mirror machine are reviewed, and relevant theoretical work is discussed. The work reported generally substantiates the quasilinear diffusion model of mirror-plasma confinement, but also suggests alternatives. The end-loss current required by theory of the drift-cyclotron loss-cone (DCLC) instability agrees with measurements of this current. The experiment indicates that an increased ratio of plasma radius to ion gyroradius improv… more
Date: May 22, 1980
Creator: Cohen, B. I.; Smith, G. R. & Berk, H. L.
Partner: UNT Libraries Government Documents Department
open access

Plasma confinement experiments in the TMX tandem mirror. Paper IAEA-CN-38/F-1

Description: Results from the new Tandem Mirror Experiment (TMX) are described. Tandem-mirror density and potential profiles are produced using end-plug neutral-beam injection and central-cell gas-fueling. TMX parameters are near those predicted theoretically. The end-plug electron temperature is higher than in the comparably sized single-mirror 2XIIB. Axial confinement of the finite-beta central-cell plasma is improved by the end plugs by as much as a factor of 9. In TMX, end-plug microinstability limits c… more
Date: May 22, 1980
Creator: Simonen, T. C.; Anderson, C. A. & Casper, T. A.
Partner: UNT Libraries Government Documents Department
open access

Harmonic generation of ion waves due to Brillouin backscattering

Description: We report results of simulations of stimulated Brillouin backscatter in which we see the second spatial harmonic of the ion density fluctuation and compare with linear, fluid theory. We also describe examples of the competition between Raman and Brillouin backscatter. 21 refs., 3 figs.
Date: May 22, 1985
Creator: Estabrook, K.; Kruer, W. L. & Haines, M. G.
Partner: UNT Libraries Government Documents Department
open access

Theory of field-reversed mirrors and field-reversed plasma-gun experiments. Paper IAEA-CN-38/R-2

Description: Experimental and theoretical studies of field reversal in a mirror machine are reported. Plasma-gun experiments demonstrate that reversed-field plasma layers are formed. Low energy plasma flowing behind the initially produced plasma front prevents tearing of the layer from the gun muzzle. MHD simulation shows that tearing can be obtained by impeding the slow plasma flow with a plasma divider. It is demonstrated theoretically that a field-reversed mirror imbedded in a multipole field can be sust… more
Date: May 22, 1980
Creator: Anderson, D.V.; Auerbach, S.P. & Berk, H.L.
Partner: UNT Libraries Government Documents Department
open access

Sulfidation of Cadmium at the Nanoscale

Description: We investigate the evolution of structures that result when spherical Cd nanoparticles of a few hundred nanometers in diameter react with dissolved molecular sulfur species in solution to form hollow CdS. Over a wide range of temperatures and concentrations, we find that rapid Cd diffusion through the growing CdS shell localizes the reaction front at the outermost CdS/S interface, leading to hollow particles when all the Cd is consumed. When we examine partially reacted particles, we find that … more
Date: May 22, 2008
Creator: Cabot, Andreu; Smith, Rachel; Yin, Yadong; Zheng, Haimei; Reinhard, Bjorn; Liu, Haitao et al.
Partner: UNT Libraries Government Documents Department
open access

ECLOUD in PS2, PS+, SPS+: AN UPDATE

Description: We present an update of our results for the electron-cloud build-up for several upgrades proposed for the LHC injectors. Specifically, we have re-examined our published results for the ecloud heat load [1] from the perspective of numerical convergence of the simulations vis-a-vis the integration time step {Delta}t. We repeated most of the simulations with ever smaller values of {Delta}t until we reached stable results, indicating numerical convergence; this was achieved at 200-500 slices per bu… more
Date: May 22, 2007
Creator: Furman, M. A.
Partner: UNT Libraries Government Documents Department
open access

Ab Initio Study of 40Ca with an Importance Truncated No-Core Shell Model

Description: We propose an importance truncation scheme for the no-core shell model, which enables converged calculations for nuclei well beyond the p-shell. It is based on an a priori measure for the importance of individual basis states constructed by means of many-body perturbation theory. Only the physically relevant states of the no-core model space are considered, which leads to a dramatic reduction of the basis dimension. We analyze the validity and efficiency of this truncation scheme using differen… more
Date: May 22, 2007
Creator: Roth, R & Navratil, P
Partner: UNT Libraries Government Documents Department
open access

Particle Simulation of Coulomb Collisions: Comparing the Methods of Takizuka & Abe and Nanbu

Description: The interactions of charged particles in a plasma are in a plasma is governed by the long-range Coulomb collision. We compare two widely used Monte Carlo models for Coulomb collisions. One was developed by Takizuka and Abe in 1977, the other was developed by Nanbu in 1997. We perform deterministic and stochastic error analysis with respect to particle number and time step. The two models produce similar stochastic errors, but Nanbu's model gives smaller time step errors. Error comparisons betwe… more
Date: May 22, 2007
Creator: Wang, C.; Lin, T.; Caflisch, R.; Cohen, B. & Dimits, A.
Partner: UNT Libraries Government Documents Department
open access

Global Cooling: Effect of Urban Albedo on Global Temperature

Description: In many urban areas, pavements and roofs constitute over 60% of urban surfaces (roof 20-25%, pavements about 40%). The roof and the pavement albedo can be increased by about 0.25 and 0.10, respectively, resulting in a net albedo increase for urban areas of about 0.1. Many studies have demonstrated building cooling-energy savings in excess of 20% upon raising roof reflectivity from an existing 10-20% to about 60%. We estimate U.S. potential savings in excess of $1 billion (B) per year in net ann… more
Date: May 22, 2007
Creator: Akbari, Hashem; Menon, Surabi & Rosenfeld, Arthur
Partner: UNT Libraries Government Documents Department
open access

Enantioselective Intramolecular Hydroarylation of Alkenes via Directed C-H Bond Activation

Description: Highly enantioselective catalytic intramolecular ortho-alkylation of aromatic imines containing alkenyl groups tethered at the meta position relative to the imine directing group has been achieved using [RhCl(coe){sub 2}]{sub 2} and chiral phosphoramidite ligands. Cyclization of substrates containing 1,1- and 1,2-disubstituted as well as trisubstituted alkenes were achieved with enantioselectivities >90% ee for each substrate class. Cyclization of substrates with Z-alkene isomers proceeded m… more
Date: May 22, 2008
Creator: Harada, Hitoshi; Thalji, Reema; Bergman, Robert & Ellman, Jonathan
Partner: UNT Libraries Government Documents Department
open access

Software Design of a General Purpose Data Acquisition and Control Executive

Description: The software design of an executive which performs general purpose data acquisition, monitoring, and control is presented. The executive runs on a memory-based mini or micro-computer and communicates with a disk-based computer where data analysis and display are done. The executive design stresses reliability and versatility, and has yielded software which can provide control and monitoring for widely different hardware systems. Applications of this software on two major fusion energy experimen… more
Date: May 22, 1981
Creator: Labiak, W. G. & Minor, E. G.
Partner: UNT Libraries Government Documents Department
open access

A test of Newton's Law of Gravity using the BREN Tower, Nevada

Description: We predicted gravity values on a tower by upward continuing an extensive set of surface data in order to test the 1/r/sup 2/ dependence of Newton's Law of Universal Gravitation. We measured gravity at 12 heights up to 454 m on a tower at the Nevada Test Site, and at 91 locations on the surface of the earth within 2.5 kilometers of the tower. These data have been combined with 60,000 surface gravity measurements within 300 kilometers of the tower and have been used to predict the gravitational f… more
Date: May 22, 1989
Creator: Kasameyer, P.; Thomas, J.; Fackler, O.; Mugge, M.; Kammeraad, J.; Millett, M. et al.
Partner: UNT Libraries Government Documents Department
open access

The. tau. one-prong problem and recent measurements by the HRS (High Resolution Spectrometer) collaboration

Description: We summarize recent measurements by the HRS collaboration of the topological branching fractions, the production cross section, the lifetime, and the rate into electrons of the {tau} lepton. An inconsistency with theoretical expectations persists at the level of two standard deviations. 11 refs., 2 figs., 4 tabs.
Date: May 22, 1989
Creator: Repond, J.
Partner: UNT Libraries Government Documents Department
open access

Integral decay-heat measurements and comparisons to ENDF/B--IV and V

Description: Results from recent integral decay-power experiments are presented and compared with summation calculations. The experiments include the decay power following thermal fission of /sup 233/U, /sup 235/U, and /sup 239/Pu. The summation calculations use ENDF/B-IV decay data and yields from Versions IV and V. Limited comparisons of experimental ..beta.. and ..gamma.. spectra with summation calculations using ENDF/B-IV are included. Generalized least-squares methods are applied to the recent /sup 235… more
Date: May 22, 1978
Creator: England, T. R.; Schenter, R. E. & Schmittroth, F.
Partner: UNT Libraries Government Documents Department
open access

Quality assurance in environmental monitoring at the Lawrence Livermore Laboratory

Description: The quality assurance program for environmental monitoring that has been developed at the Lawrence Livermore Laboratory (LLL) consists of procedure documentation, replicate field-sample analysis, and participation in intercomparison measurements. Sampling, analytical, data processing, and record keeping procedures are described. A replicate-sample collection schedule has been established for all media sampled at LLL. At present, blind-spiked samples are not utilized. Flow rates of air samplers … more
Date: May 22, 1978
Creator: Lindeken, C. L.; White, J. H. & Silver, W. J.
Partner: UNT Libraries Government Documents Department
open access

['UNT professor offers expertise of Barnes collection', May 22, 1994]

Description: An article from the newspaper the Denton Record-Chronicle written by Tim Leenerts. The piece discusses the lectures given by Dr. R. William McCarter on the Barnes collection, which was being shown at the Kimbell Art Museum in Fort Worth.
Date: May 22, 1994
Creator: Leenerts, Tim
Partner: UNT Libraries Special Collections
open access

Physics goals and signatures at the SSC

Description: The physics goals of the SSC are presented and the capabilities of the SSC to achieve them are assessed. New gauge bosons, electroweak symmetry breaking, supersymmetry, and quark substructure are the primary targets for particle physics research and the SSC is the most effective means to find them. 2 refs., 4 figs.
Date: May 22, 1990
Creator: Cahn, R.N.
Partner: UNT Libraries Government Documents Department
open access

Basic criticality relations for gas core design

Description: Minimum critical fissile concentrations are calculated for U-233, U-235, Pu-239, and Am-242m mixed homogeneously with hydrogen at temperatures to 15,000K. Minimum critical masses of the same mixtures in a 1000 liter sphere are also calculated. It is shown that propellent efficiencies of a gas core fizzler engine using Am-242m as fuel would exceed those in a solid core engine as small as 1000L operating at 100 atmospheres pressure. The same would be true for Pu-239 and possibly U-233 at pressure… more
Date: May 22, 1992
Creator: Tanner, J. E.
Partner: UNT Libraries Government Documents Department
open access

Geobotanical Remote Sensing for Geothermal Exploration

Description: This paper presents a plan for increasing the mapped resource base for geothermal exploration in the Western US. We plan to image large areas in the western US with recently developed high resolution hyperspectral geobotanical remote sensing tools. The proposed imaging systems have the ability to map visible faults, surface effluents, historical signatures, and discover subtle hidden faults and hidden thermal systems. Large regions can be imaged at reasonable costs. The technique of geobotanica… more
Date: May 22, 2001
Creator: Pickles, W. L.; Kasameyer, P. W.; Martini, B. A.; Potts, D. C. & Silver, E. A.
Partner: UNT Libraries Government Documents Department
open access

Certification Testing and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen Storage

Description: Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen or ambient-temperature compressed hydrogen. This flexibility results in multiple advantages with respect to compressed hydrogen tanks or low-pressure liquid hydrogen tanks. Our work is directed at verifying that commercially available aluminum-lined, fiber-wrapped pressure vessels can be safely used to store liquid hydrogen. A series of tests have been conducted, and the results indicate th… more
Date: May 22, 2002
Creator: Aceves, S. M.; Martinez-Frias, J. & Espinosa-Loza, F.
Partner: UNT Libraries Government Documents Department
open access

Heavy Quarkonium Production at LHC through W Boson Decays

Description: The production of the heavy (c{bar c})-quarkonium, (c{bar b})-quarkonium, and (b{bar b})-quarkonium states [({bar Q}') quarkonium for short], via the W{sup +} semi-inclusive decays, has been systematically studied within the framework of the nonrelativistic QCD. In addition to the two color-singlet S-wave states, we also discuss the production of the four color-singlet P-wave states |(Q{bar Q}')({sup 1}P{sub 1}){sub 1}> and |(Q{bar Q}')({sup 3}P{sub J}){sub 1}> [with J = (0,1,2)] together… more
Date: May 22, 2012
Creator: Liao, Qi-Li; U., /Chongqing; Wu, Xing-Gang; /SLAC, /Chongqing U.; Jiang, Jun; Yang, Zhi et al.
Partner: UNT Libraries Government Documents Department
open access

RADIOLOGICAL SURVEY STATION DEVELOPMENT FOR THE PIT DISASSEMBLY AND CONVERSION PROJECT

Description: The Savannah River National Laboratory (SRNL) has developed prototype equipment to demonstrate remote surveying of Inner and Outer DOE Standard 3013 containers for fixed and transferable contamination in accordance with DOE Standard 3013 and 10 CFR 835 Appendix B. When fully developed the equipment will be part of a larger suite of equipment used to package material in accordance with DOE Standard 3013 at the Pit Disassembly and Conversion Project slated for installation at the Savannah River S… more
Date: May 22, 2011
Creator: Dalmaso, M.; Gibbs, K. & Gregory, D.
Partner: UNT Libraries Government Documents Department
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