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Gene conversion in yeast as a function of linear energy transfer (LET) for low-LET radiation

Description: The relative biological effectiveness (RBE) for low-LET radiation is known to depend on such factors as LET and dose rate. Microdosimetric calculations indicate that the biological target size could also be an important parameter, and calculations predict that the RBE for effects produced by hits in target sizes below about 100 nm should be unity for all low LET radiation. We have measured that RBE for gene conversion in yeast (a small target) for five different low LET photon sources, and the … more
Date: May 1, 1992
Creator: Unrau, P.; Morrison, D.P. (Pacific Northwest Lab., Richland, WA (United States)) & Johnson, J.R. (Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.)
Partner: UNT Libraries Government Documents Department
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Metal vapor vacuum arc (MEVVA) high current ion source

Description: An ion source is described in which a metal vapor vacuum arc is used to create the plasma from which the ions are extracted. Beams of a variety of ions have been produced, ranging from lithium up to uranium. At an extraction voltage of 25 kV we've measured an ion beam current of over 1 Ampere, with over 550 ema of the beam in an emittance of 0.07..pi.. cm. mradians (normalized). The ion charge state distribution varies with cathode material and with arc power; for uranium a typical distribution… more
Date: May 1, 1985
Creator: Brown, I.G.
Partner: UNT Libraries Government Documents Department
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Difficulties with inferring neutron cross sections from charged-particle reactions

Description: We have investigated problems associated with inferring cross sections for neutron reactions on unstable nuclei in the mass-90 region from charged-particle reactions on nearby stable targets. We conclude that effects due to precompound evaporation, isospin, and multiple reaction paths severely limit the circumstances under which charged-particle studies may be directly and easily converted to neutron cross sections of useful accuracy. 4 refs., 2 figs.
Date: May 7, 1985
Creator: Gardner, D. G. & Gardner, M. A.
Partner: UNT Libraries Government Documents Department
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Proceedings of the Workshop on Program Options in Intermediate-Energy Physics. Keynote address: New directions in elementary particle physics - pantip from very low to very high energies

Description: The recent development of cooling techniques offers the possibility to obtain intense sources of antiprotons, stacking them as they are produced at a multi-GeV accelerator. The wide array of applications presently considered, ranging from reactions at extremely low energy in the case of p anti p atoms to reactions at hundreds of GeV in the case of head-on collisions between protons and antiprotons accelerated at the same time in a super synchrotron, is reviewed. Special emphasis is put on the p… more
Date: May 1, 1980
Creator: Jacob, M.
Partner: UNT Libraries Government Documents Department
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Construction and testing of a double acting bellows liquid helium pump

Description: The double acting reciprocating bellows liquid helium pump built and tested at the Lawrence Berkeley Laboratory is described. The pump is capable of delivering 50 gs/sup -1/ of liquid helium to supply the two-phase cooling sytem for a large superconducting magnet. The pump is driven by a torque motor at room temperature; the reciprocating motion is transmitted to the pump through a shaft which operates between room temperature and 4/sup 0/K. The design details of this liquid helium pump are pre… more
Date: May 1, 1980
Creator: Burns, W. A.; Green, M. A.; Ross, R. R. & Van Slyke, H.
Partner: UNT Libraries Government Documents Department
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Compact heavy ion RFQ preaccelerator for use at the CERN Linac I

Description: This paper describes the LBL contribution to a project designed to provide fully-stripped oxygen beams for acceleration in the CERN PS complex. A preaccelerator for Linac I, consisting of an ECR ion source, an RFQ linac, and rf matching cavities, is being assembled as part of a collaborative arrangement among LBL, GSI, and CERN. The RFQ, designed and built at LBL, will accept analyzed oxygen +6 beam from the ECR at 5.6 keV/amu, and accelerate it to 139.5 keV/amu, the injection energy required f… more
Date: May 1, 1985
Creator: Gough, R.A.; Staples, J.; Caylor, R.; Howard, D.; MacGill, R. & Tanabe, J.
Partner: UNT Libraries Government Documents Department
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LBL neutralized beam focusing experiment

Description: An intense neutralized Cs/sup +1/ beam has been focused by an electrostatic polarization field induced by a solenoidal magnetic field of 10-25 gauss. This report describes the experiment and compares the results with the predictions of an analytic linearized fluid model and a particle-in-cell simulation which treats the motion of the warm electrons in detail.
Date: May 1, 1985
Creator: Krafft, G. A.; Kim, C. H. & Smith, L.
Partner: UNT Libraries Government Documents Department
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Working Group summary reports from the Advanced Photon Source reliability workshop

Description: A workshop was held at APS to address reliability goals for accelerator systems. Seventy-one individuals participated in the workshop, including 30 from other institutions. The goals of the workshop were to: (1) Give attendees an introduction to the basic concepts of reliability analysis. (2) Exchange information on operating experience at existing accelerator facilities and strategies for achieving reliability at facilities under design or in construction. (3) Discuss reliability goals for APS… more
Date: May 1, 1992
Partner: UNT Libraries Government Documents Department
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Anti p-nucleus interaction

Description: Status and future prospects of antiproton-nucleus scattering experiments are presented. These scattering experiments were conducted at antiproton beam momentums of 300 and 600 MeV/c on target nuclei of /sup 6/Li, /sup 12/C, /sup 16/O, /sup 18/O, /sup 40/Ca, /sup 48/Ca, and /sup 208/Pb. Antiproton-proton reactions investigated antiproton-nucleus bound or resonant states in antiproton reactions with d, /sup 6/Li, /sup 12/C, /sup 63/Cu, and /sup 209/Bi. Inelastic scattering experiments investigate… more
Date: May 1, 1986
Creator: Peng, J.C.
Partner: UNT Libraries Government Documents Department
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SOLSTEP: a computer model for predicting the thermodynamic and economic performance of solar thermal power plants

Description: A thermodynamic and economic performance analysis code, SOLSTEP, was developed to facilitate the evaluation of solar thermal power plant designs. The code conducts a time step simulation of the plant thermodynamic performance using actual recorded meteorological and insolation data. Each analysis case provides capacity factor and levelized energy cost results for several plant configurations using various combinations of collector field size and storage capacity. The code has been used to analy… more
Date: May 1, 1979
Creator: Bird, S. P.
Partner: UNT Libraries Government Documents Department
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Report of the group on beam-beam effects in circular colliders

Description: We present a summary of the discussions and conclusions of the working group on beam-beam effects for circular colliders. This group was part of the larger beam-beam dynamics group at the 7th ICFA Workshop on Beam Dynamics, on the subject Beam-Beam and Beam-Radiation Interactions,'' held at UCLA, May 13--16, 1991. 15 refs.
Date: May 1, 1991
Creator: Furman, M. A.
Partner: UNT Libraries Government Documents Department
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Search for new effects in e/sup +/e/sup -/ interactions

Description: Recent measurements of R, the ratio of the total hadron cross section to the lowest order muon pair cross section, are discussed which have systematic overall scale errors on the absolute value of R of 7% or less. Experiments are reviewed that have sought exotic effects in e/sup +/e/sup -/ at the highest available energies. The search for narrow states in the radiative decays of the J/psi and UPSILON are also reviewed. 35 refs., 24 figs. (LEW)
Date: May 1, 1985
Creator: Bloom, E.D.
Partner: UNT Libraries Government Documents Department
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Studies of the Formation of Field Reversed Plasma by a Magnetized Co-Axial Plasma Gun

Description: The gun injects axially into a drift tank followed by a magnetic mirror. For the experiments reported here, only the guide coils outside the vacuum vessel and solenoids on the plasma gun electrodes were used; the mirror coil was not energized. A stainless steel flux conserver is placed in the mirror throat to prevent the plasma from contacting the nonconducting vacuum wall in the region of the mirror. An axis encircling array of magnetic loop probes includes four diamagnetic loops and a loop wh… more
Date: May 28, 1980
Creator: Turner, W. C.; Granneman, E. H. A.; Hartman, C. W.; Prono, D. S.; Taska, J. & Smith, A. C., Jr.
Partner: UNT Libraries Government Documents Department
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Perspective on photovoltaic amorphous silicon

Description: Amorphous silicon is a thin film option that has the potential for a cost-effective product for large-scale utility photovoltaics application. The initial efficiencies for single-junction and multijunction amorphous silicon cells and modules have increased significantly over the past 10 years. The emphasis of research and development has changed to stabilized efficiency, especially that of multijunction modules. NREL has measured 6.3%--7.2% stabilized amorphous silicon module efficiencies for U… more
Date: May 1, 1992
Creator: Luft, W.; Stafford, B. & von Roedern, B.
Partner: UNT Libraries Government Documents Department
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Movable Genetic Elements: Detection of Changes in Maize DNA at the Shrunken Locus Due to the Intervention of Ds Elements

Description: This report describes our initial attempts at the molecular characterization of a maize controlling element. We have prepared a cDNA probe and used it to detect changes at a locus where Ds elements are found. Evidence of their presence are indicated by changes in the restriction patterns, but there is as yet no information on the physical nature of the controlling elements nor on the kinds of rearrangements they cause.
Date: May 28, 1980
Creator: Burr, B. & Burr, F.A.
Partner: UNT Libraries Government Documents Department
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Conservation and economic development

Description: This oral presentation is about the Espanola Power Savers Project which involves both the utility and for the community. I'm going to spend much of my time today discussing why this project makes sense for the community, but I would like to start with a brief word about why community-based conservation makes sense for utilities. A number of reasons are listed to show why conservation is today's energy resource of choice. But if, for a moment, we take that as a given and ask why community-based … more
Date: May 1, 1992
Creator: Sullivan, M.J.
Partner: UNT Libraries Government Documents Department
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Interim results of the F-5 irradiation experiment and proposed fission product transport mechanisms

Description: This paper presents: (1) results of a study of gamma-scan data for eight fuel rods removed at the end of the first phase of the GCFR F-5 (X317) irradiation experiment in EBR-II; (2) a comparison of cesium and iodine migration behavior in F-5 and previous GCFR irradiation experiments (GB-9, GB-10, and F-1); and (3) proposed cesium and iodine transport mechanisms, based primarily on observed fission product behavior in the irradiation experiments. Two modes of cesium transport, metal vapor transp… more
Date: May 1, 1980
Creator: Bell, W.E.; Greenberg, S.; Goodin, D.T. & Langer, S.
Partner: UNT Libraries Government Documents Department
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Application of a dc SQUID to rf Amplification: NQR

Description: Superconducting QUantum Interference Devices (SQUIDs) have been used for more than a decade for the detection of magnetic resonance. Until recently, these devices had mostly been confined to operation in the audiofrequency range, so that experiments have been restricted to measurements of resonance at low frequencies, or of changes in the static susceptibility of a sample induced by rf irradiation at the resonant frequency. However, the recent extension of the operating range of low noise dc SQ… more
Date: May 1, 1985
Creator: Hilbert, C.; Clarke, J.; Sleator, T. & Hahn, E. L.
Partner: UNT Libraries Government Documents Department
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Study of short-range motion of atomic hydrogen in amorphous silicon by neutron reflectometry

Description: Preliminary results of neutron reflectometry (NR) measurements on rf sputter-deposited a-Si:H/a-Si:D bilayers indicate that this technique may be used to monitor H and D motions over distances of {approx} 10 to 200 {Angstrom} with a nominal resolution of 5--10 {Angstrom}. In studying rf sputter-deposited thin films containing a high density of microvoids annealed at 270 C, we found that the hydrogen diffused a distance of only {approx} 100 {Angstrom}. Further annealing at 270 and 280 C produced… more
Date: May 1, 1992
Creator: Dozier, W.D. (Argonne National Lab., IL (United States)); Herwig, K.W. (Missouri Univ., Columbia, MO (United States). Research Reactor Facility); Shinar, R. (Iowa State Univ. of Science and Technology, Ames, IA (United States). Microelectronics Research Center); Jia, H. & Shinar, J. (Ames Lab., IA (United States))
Partner: UNT Libraries Government Documents Department
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Status of European appliance standards

Description: The European Community (EC) recently commissioned a study of the impact of potential appliance standards on electricity consumption in the twelve EC nations. This study looks at refrigerators, freezers, dishwashers, clothes washers, and clothes dryers. The impact of minimum efficiency standards on electricity use over the time period from 1995--2010 is estimated. The results of this study were presented to the EC in September of 1991. Revisions were made to the draft report and final copies sen… more
Date: May 1, 1992
Creator: Turiel, I. (Lawrence Berkeley Lab., CA (United States)) & Lebot, B. (Agence de L'Environnement et de la Maitrise de L'Energie, Valbonne (France))
Partner: UNT Libraries Government Documents Department
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Analytical methods of electrode design for a relativistic electron gun

Description: The standard paraxial ray equation method for the design of electrodes for an electrostatically focused gun is extended to include relativistic effects and the effects of the beam's azimuthal magnetic field. Solutions for parallel and converging beams are obtained and the predicted currents are compared against those measured on the High Brightness Test Stand. 4 refs., 2 figs.
Date: May 9, 1985
Creator: Caporaso, G.J.; Cole, A.G. & Boyd, J.K.
Partner: UNT Libraries Government Documents Department
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