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Use of molybdenum ion source electrodes at RTNS-II

Description: Reports are reported for an ongoing effort to optimize D+ beam production by the MATS-III ion source used at RTNS-II. The three seven-aperture electrodes, originally consisting of water-cooled copper, have now been tested using uncooled molybdenum and with water cooling on the second (decel) electrode only. Details of the change, the results of the testing, and the benefits in operation, performance and cost are given.
Date: September 29, 1986
Creator: Massoletti, D.J.; Harter, G.A. & Heikkinen, D.W.
Partner: UNT Libraries Government Documents Department
open access

Structure functions: Their status and implications

Description: I discuss the current status of structure functions. Attention is given to the uncertainties in them and the implications of these uncertainties for experimental predictions. I indicate which experiments are capable of removing these uncertainties. 17 refs., 17 figs., 1 tab.
Date: September 29, 1988
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
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Oxide cathode lifetime improvements at RTNS-II

Description: Results are reported for an ongoing effort to optimize D/sup +/ beam production by the MATS-III ion source used at the RTNS-II. The oxide cathode assembly originally designed for lower power operation has been modified and redesigned for higher electron current yield, longer life and serviceability. A factor of 2.5 has been gained in cathode lifetime due to these changes. The details of the changes and results and benefits in operation and performance are given. In addition, the technique used … more
Date: September 29, 1986
Creator: Massoletti, D.J.
Partner: UNT Libraries Government Documents Department
open access

Compact 80-keV neutral-beam module

Description: A compact and maintainable source of 80-keV neutral beams that focus to a high power density is required for the Mirror Fusion Test Facility (MFTF). In the new source being designed and built to meet these requirements, the cross-sectional area is reduced in two ways: by immersing the source in a vacuum where high voltage can be held over smaller distances and by redesigning grid supporting structures. Reliability is increased by reducing the electric fields everywhere else below those present … more
Date: September 29, 1977
Creator: Molvik, A. W.; Baird, E. D.; Berkner, K. H.; Cooper, W. S.; Duffy, T. J.; Ehlers, K. W. et al.
Partner: UNT Libraries Government Documents Department
open access

4. pi. interferometric measurements of laser fusion targets

Description: Apparatus is described for rapidly manipulating a hollow glass microsphere laser fusion target and scanning the entire wall with a double pass interference microscope.
Date: September 29, 1977
Creator: Weinstein, B.W.; Willenborg, D.L.; Weir, J.T. & Hendricks, C.D.
Partner: UNT Libraries Government Documents Department
open access

Regulated 15-V, 7500-A, neutral-beam filament supply

Description: Lawrence Livermore Laboratory (LLL) designed a cost-effective, regulated 15-V, 7500-A filament supply for use with the High-Voltage Test Stand , a major ERDA developmental neutral-beam test facility. The filament supply can float to 200 kV and can provide pulse widths up to 30 s. Powered by a 24-V, 0.5-TJ battery bank, it avoids the use of expensive isolation transformers and induction voltage regulators (IVR's). Battery output is regulated by a water-cooled resistor-contactor combination in wh… more
Date: September 29, 1977
Creator: Reass, W.
Partner: UNT Libraries Government Documents Department
open access

Tradeoffs in capacitor bank design

Description: When designing a capacitor bank for energy storage, the engineer should not use more capacitors, voltage, or energy than necessary to supply the load and to overcome losses. Universal curves presented here aid the designer in making intelligent choices. For example, there is a minimum stored energy to be achieved, but no minimum voltage at which to store it. Included in the curves are the effects of series losses such as voltage drops in regulator tubes or in current-limiting resistors. Capacit… more
Date: September 29, 1977
Creator: Leavitt, G.A.
Partner: UNT Libraries Government Documents Department
open access

Design study of a DPIS injector for a heavy ion FFAG

Description: A new heavy ion injector linac is proposed for providing heavy ion beams to a fixed field alternating gradient (FFAG) accelerator in Kyushu University. A combination of the new intense laser source based injector and the FFAG will be able to accelerate high current ion beams with 100 Hz of a repetition rate. The planned average current reaches 7 {micro}A with carbon 6+ beam.
Date: September 29, 2008
Creator: Okamura,M.; Raparia, D.; Ishibashi, K.; Yonemura, Y. & Kanesue, T.
Partner: UNT Libraries Government Documents Department
open access

Design and Construction Solutions in the Accurate Realization of NCSX Magnetic Fields

Description: The National Compact Stellarator Experiment, NCSX, is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in partnership with the Oak Ridge national Laboratory. The goal of NCSX is to provide the understanding necessary to develop an attractive, disruption free, steady state compact stellaratorbased reactor design. This paper describes the recently revised designs of the critical interfaces between the modular coils, the construction solutions developed to meet assembly toleranc… more
Date: September 29, 2008
Creator: Heitzenroeder, P.; Dudek, Lawrence E.; Brooks, Arthur W.; Viola, Michael E.; Brown, Thomas; Neilson, George H. et al.
Partner: UNT Libraries Government Documents Department
open access

LONGITUDINAL RESISTIVE INSTABILITIES OF INTENSE COASTING BEAMS IN PARTICLE ACCELERATORS

Description: The effect of finite resistance in the vacuum-tank walls on the longitudinal stability of an intense beam of particles in an accelerator is investigated theoretically. We show that even if the particle frequency is an increasing function of particle energy, the wall resistance can render the beam unstable against longitudinal bunching. In the absence of frequency spread in the unperturbed beam, the instability occurs with a growth rate that is proportional to (N/{sigma}){sup 1/2}, where N is th… more
Date: September 29, 1964
Creator: Neil, V. Kelvin & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
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Dynamic Response of Copper Subjected to Quasi-Isentropic, Gas-Gun Driven Loading

Description: A transmission electron microscopy study of quasi-isentropic high-pressure loading (peak pressures between 18 GPa and 52 GPa) of polycrystalline and monocrystalline copper was carried out. Deformation mechanisms and defect substructures at different pressures were analyzed. Current evidence suggests a deformation substructure consisting of twinning at the higher pressures and heavily dislocated laths and dislocation cells at the intermediate and lower pressures, respectively. Evidence of stacki… more
Date: September 29, 2005
Creator: Jarmakani, H.; McNaney, J. M.; Schneider, M. S.; Orlikowski, D.; Nguyen, J. H.; Kad, B. et al.
Partner: UNT Libraries Government Documents Department
open access

Laser-based profile and energy monitor for H beams

Description: A beam profile and energy monitor for H{sup -} beams based on laser photoneutralization was built at Brookhaven National Laboratory (BNL)* for use on the High Intensity Neutrino Source (HMS) at Fermilab. An H{sup -} ion has a first ionization potential of 0.75eV and can be neutralized by light from a Nd:YAG laser ({lambda}=1064nm). To measure beam profiles, a narrow laser beam is stepped across the ion beam, removing electrons from the portion of the H{sup -} beam intercepted by the laser. Thes… more
Date: September 29, 2008
Creator: Connolly, R.; Alessi, J.; Bellavia, S.; Dawson, C.; Degen, C.; Meng, W. et al.
Partner: UNT Libraries Government Documents Department
open access

Status of DPIS development in BNL

Description: Direct injection scheme was proposed in 2000 at RIKEN in Japan. The first beam test was done at Tokyo Institute of Technology using a CO{sub 2} laser and an 80 MHz 4 vane RFQ in 2001, and further development continued in RIKEN. In 2006, all the experimental equipment were moved to BNL and a new development program was started. We report on our recent activities at BNL including the use of a frozen gas target for the laser source, low charge state ion beam production and a newly developed laser … more
Date: September 29, 2008
Creator: Okamura,M.; Tamura, J. & Kanesue, T.
Partner: UNT Libraries Government Documents Department
open access

Ionic Liquids: Radiation Chemistry, Solvation Dynamics and Reactivity Patterns

Description: Ionic liquids (ILs) are a rapidly expanding family of condensed-phase media with important applications in energy production, nuclear fuel and waste processing, improving the efficiency and safety of industrial chemical processes, and pollution prevention. ILs are generally nonvolatile, noncombustible, highly conductive, recyclable and capable of dissolving a wide variety of materials. They are finding new uses in chemical synthesis, catalysis, separations chemistry, electrochemistry and other … more
Date: September 29, 2008
Creator: Wishart, J. F.
Partner: UNT Libraries Government Documents Department
open access

Rap1 integrates tissue polarity, lumen formation, and tumorigenicpotential in human breast epithelial cells

Description: Maintenance of apico-basal polarity in normal breast epithelial acini requires a balance between cell proliferation, cell death, and proper cell-cell and cell-extracellular matrix signaling. Aberrations in any of these processes can disrupt tissue architecture and initiate tumor formation. Here we show that the small GTPase Rap1 is a crucial element in organizing acinar structure and inducing lumen formation. Rap1 activity in malignant HMT-3522 T4-2 cells is appreciably higher than in S1 cells,… more
Date: September 29, 2006
Creator: Itoh, Masahiko; Nelson, Celeste M.; Myers, Connie A. & Bissell,Mina J.
Partner: UNT Libraries Government Documents Department
open access

Plasma Performance Improvement with Lithium-Coated Plasma-Facing Components in NSTX

Description: Lithium as a plasma-facing material has many attractive features, including a reduction in the recycling of hydrogenic species and the potential for withstanding high heat and neutron fluxes in fusion reactors. Recent NSTX experiments have shown, for the first time, significant and recurring benefits of lithium coatings on plasma-facing components (PFC's) to the performance of divertor plasmas in both L- and H- mode confinement regimes heated by high-power neutral beams. They included decreases… more
Date: September 29, 2008
Creator: Kaita, R., et. al.
Partner: UNT Libraries Government Documents Department
open access

EBIS preinjector construction status

Description: A new heavy ion preinjector is presently under construction at Brookhaven National Laboratory. This preinjector uses an Electron Beam Ion Source (EBIS), and an WQ and IH Linac, both operating at 100.625 MHz, to produce 2 MeV/u ions of any species for use, after further acceleration, at the Relativistic Heavy Ion Collider, and the NASA Space Radiation Laboratory. Among the increased capabilities provided by this preinjector are the ability to produce ions of any species, and the ability to switc… more
Date: September 29, 2008
Creator: Alessi,J.; Barton, D.; Beebe, E.; Bellavia, S.; Gould, O.; Kponou, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Tools and methods for implementing the control systems on the Mirror Fusion Test Facility

Description: Installation of the major hardware subsystems for MFTF is nearing completion. These subsystems include the Fusion Chamber System, the eighty KV Neutral Beam System, the Superconducting Magnet System, and the Personnel Safety System. The Local Controls group has undertaken a uniform aproach to implementing the control systems for all of these hardware subsystems. This approach has two major aspects: (1) to provide a stand-alone computer control system with a remote, portable terminal so that com… more
Date: September 29, 1981
Creator: Minor, E. G. & Labiak, W. G.
Partner: UNT Libraries Government Documents Department
open access

Debugging in a multi-processor environment

Description: The Supervisory Control and Diagnostic System (SCDS) for the Mirror Fusion Test Facility (MFTF) consists of nine 32-bit minicomputers arranged in a tightly coupled distributed computer system utilizing a share memory as the data exchange medium. Debugging of more than one program in the multi-processor environment is a difficult process. This paper describes what new tools were developed and how the testing of software is performed in the SCDS for the MFTF project.
Date: September 29, 1981
Creator: Spann, J.M.
Partner: UNT Libraries Government Documents Department
open access

The LLNL CR-39 personnel neutron dosimeter

Description: We developed a personnel neutron dosimetry system based on the electrochemical etching of CR-39 plastic at elevated temperatures. The doses obtained using this dosimeter system are more accurate than those obtained using other dosimetry systems, especially when varied neutron spectra are encountered. This CR-39 dosimetry system does not have the severe energy dependence that exists with albedo neutron dosimeters or the fading and reading problems encountered with NTA film. 3 refs., 4 figs.
Date: September 29, 1987
Creator: Hankins, D.E.; Homann, S. & Westermark, J.
Partner: UNT Libraries Government Documents Department
open access

DC gradient-B pumping of tandem-mirror thermal barriers

Description: Passive pumping of tandem-mirror thermal barriers by a combination of E x B and gradient magnetic field (grad-B) drifts has the advantages of engineering simplicity, low power consumption and selectivity in pumping out trapped thermal ions while retaining high-energy sloshing ions, hot electrons, and central-cell ions. Specifically, installing dc perturbation coils in suitable locations utilizes the differences in the turning points of these populations. In addition, we can dispose of the therm… more
Date: September 29, 1981
Creator: Hamilton, G.W.
Partner: UNT Libraries Government Documents Department
open access

Geothermal energy: the resource and the environment

Description: A general overview of geothermal energy is presented. The current usage, geological origin, and environmental effects of geothermal development are summarized with emphasis on the numerous facets of the resource that may be singled out by interested individuals for further study. The conclusion is made that total geothermal development will be but a small percentage of the U.S. energy requirement, but that geothermal energy is and will be regionally significant as an energy resource.
Date: September 29, 1978
Creator: Arnold, H.G.
Partner: UNT Libraries Government Documents Department
open access

Plastic dislocation motion via nonequilibrium molecular and continuum dynamics

Description: The classical two-dimensional close-packed triangular lattice, with nearest-neighbor spring forces, is a convenient standard material for the investigation of dislocation motion and plastic flow. Two kinds of calculations, based on this standard material, are described here: (1) Molecular Dynamics simulations, incorporating adiabatic strains described with the help of Doll's Tensor, and (2) Continuum Dynamics simulations, incorporating periodic boundaries and dislocation interaction through str… more
Date: September 29, 1980
Creator: Hoover, W. G.; Ladd, A. J. C. & Hoover, N. E.
Partner: UNT Libraries Government Documents Department
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