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Design and development of neutral beam module components (open access)

Design and development of neutral beam module components

The Mirror Fusion Test Facility (MFTF) injection system consists of twenty 20 keV start-up, and twenty-four 80 keV sustaining neutral beam source modules. The neutral beam modules are mounted in four clusters equally spaced around the waist of the vacuum vessel which contains the superconducting magnets. A module is defined here as an assembly consisting of a beam source and the interfacing components between that beam source and the vacuum chamber. Six major interfacing components are the subject of this paper. They are the magnetic shield, the neutralizer duct, the isolation valve, mounting gimbals, aiming bellows and actuators.
Date: November 13, 1979
Creator: Holl, P. M.; Bulmer, R. H.; Dilgard, L. W.; Horvath, J. A.; Molvik, A. W.; Porter, G. D. et al.
System: The UNT Digital Library
Design of the MFTF external vacuum system (open access)

Design of the MFTF external vacuum system

As a result of major experiment success in the LLL mirror program on start-up and stabilization of plasmas in minimum-B magnetic geometry, a Mirror Fusion Test Facility (MFTF) is under construction. Completion is scheduled for September, 1981. MFTF will be used to bridge the gap between present day small mirror experiments and future fusion-reactor activity based on magnetic mirrors. The focal point of the Mirror Fusion Test Facility is the 35 foot diameter by 60 foot long vacuum vessel which encloses the superconducting magnets. High vacuum conditions in the vessel are required to establish and maintain a plasma, and to create and deliver energetic neutral atoms to heat the plasma at the central region.
Date: November 13, 1979
Creator: Holl, P. M.
System: The UNT Digital Library
Designing MFTF thermal absorbers (open access)

Designing MFTF thermal absorbers

Both ion dumps and neutral beam dumps have been designed for the Mirror Fusin Test Facility (MFTF) at the Lawrence Livermore Laboratory. Engineering and design has been completed, and fabrication will be contracted to industrial firms in late 1979. This paper presents the performance requirements, heat density, and heat distribution on both dumps. The thermal analysis for determining the dumps' size and methods for cooling them are discussed. Attention is also directed to mechanical design and fabrication as well as to leading-edge design thermal panels.
Date: November 13, 1979
Creator: Chang, Y.
System: The UNT Digital Library
Final design of the neutral beam lines for the Tokamak Fusion Test Reactor (open access)

Final design of the neutral beam lines for the Tokamak Fusion Test Reactor

Final design of the neutral beam lines for TFTR has been completed. A prototype has been assembled at Lawrence Berkeley Laboratory and is undergoing testing as part of the Neutral Beam System Test Facility (NBSTF). The final neutral beam line (NBL) configuration differs in several details from that previously reported upon; certain components have been added; and testing of the cryopump system has led to some design simplification. It is these developments which are reported herein.
Date: November 13, 1979
Creator: Pittenger, L.C.; Valby, L.E.; Stone, R.R.; Pedrotti, L.R.; Denhoy, B. & Yoard, R.
System: The UNT Digital Library
High density energy storage capacitor (open access)

High density energy storage capacitor

The Nova laser system will use 130 MJ of capacitive energy storage and have a peak power capability of 250,000 MW. This capacitor bank is a significant portion of the laser cost and requires a large portion of the physical facilities. In order to reduce the cost and volume required by the bank, the Laser Fusion Program funded contracts with three energy storage capacitor producers: Aerovox, G.E., and Maxwell Laboratories, to develop higher energy density, lower cost energy storage capacitors. This paper describes the designs which resulted from the Aerovox development contract, and specifically addresses the design and initial life testing of a 12.5 kJ, 22 kV capacitor with a density of 4.2 J/in/sup 3/ and a projected cost in the range of 5 cents per joule.
Date: November 13, 1979
Creator: Whitham, K.; Howland, M. M. & Hutzler, J. R.
System: The UNT Digital Library
Miniature specimen technology for postirradiation fatigue crack growth testing (open access)

Miniature specimen technology for postirradiation fatigue crack growth testing

Current magnetic fusion reactor design concepts require that the fatigue behavior of candidate first wall materials be characterized. Fatigue crack growth may, in fact, be the design limiting factor in these cyclic reactor concepts given the inevitable presence of crack-like flaws in fabricated sheet structures. Miniature specimen technology has been developed to provide the large data base necessary to characterize irradiation effects on the fatigue crack growth behavior. An electrical potential method of measuring crack growth rates is employed on miniature center-cracked-tension specimens (1.27 cm x 2.54 cm x 0.061 cm). Results of a baseline study on 20% cold-worked 316 stainless steel, which was tested in an in-cell prototypic fatigue machine, are presented. The miniature fatigue machine is designed for low cost, on-line, real time testing of irradiated fusion candidate alloys. It will enable large scale characterization and development of candidate first wall alloys.
Date: November 13, 1979
Creator: Mervyn, D.A. & Ermi, A.M.
System: The UNT Digital Library
Mirror Fusion Test Facility magnet (open access)

Mirror Fusion Test Facility magnet

The Mirror Fusion Test Facility (MFTF) is the largest of the mirror program experiments for magnetic fusion energy. It seeks to combine and extend the near-classical plasma confinement achieved in 2XIIB with the most advanced neutral-beam and magnet technologies. The product of ion density and confinement time will be improved more than an order of magnitude, while the superconducting magnet weight will be extrapolated from the 15 tons in Baseball II to 375 tons in MFTF. Recent reactor studies show that the MFTF will traverse much of the distance in magnet technology towards the reactor regime. Design specifics of the magnet are given. (MOW)
Date: November 13, 1979
Creator: Henning, C. H.; Hodges, A. J.; Van Sant, J. H.; Hinkle, R. E.; Horvath, J. A.; Hintz, R. E. et al.
System: The UNT Digital Library
Tandem mirror magnet system for MFTF. [MFTF-B] (open access)

Tandem mirror magnet system for MFTF. [MFTF-B]

The Lawrence Livermore Laboratory (LLL) is planning a major extension to the Mirror Fusion Test Facility (MFTF) now under construction at Livermore, CA. This extension brings MFTF to a full tandem mirror configuration, incorporating new ideas for improved plasma confinement. The tandem MFTF is tentatively called MFTF-B. As with most magnetic fusion devices, the confinement coils dominate the overall configuration. This paper concentrates on the MFTF-B magnet configuration, especially field shaping and structural considerations. (MOW)
Date: November 13, 1979
Creator: Bulmer, R. H.
System: The UNT Digital Library
Clinch River Breeder Reactor Plant steam generator: FEW tube test model post test examination (open access)

Clinch River Breeder Reactor Plant steam generator: FEW tube test model post test examination

The Steam Generator Few Tube Test (FTT) is part of an extensive testing program being carried out in support of the Clinch River Breeder Reactor Plant (CRBRP) steam generator design. The testing of full-length seven-tube evaporator and three-tube superheater models of the CRBRP design was conducted to provide steady-state thermal/hydraulic performance data to full power per tube and to verify the absence of multi-year endurance problems. The problems encountered with the mechanical features of the FTT model design which led to premature test termination and the results of the post-test examination are described.
Date: September 13, 1979
Creator: Impellezzeri, J. R. & Camaret, T. L.
System: The UNT Digital Library
Consequences of intensity constraints on inertial confinement fusion (open access)

Consequences of intensity constraints on inertial confinement fusion

It is shown that the conflicting requirements of high implosion efficiency (low corona temperature) and adequate energy transport (high corona temperature) can, together with other effects, limit useful infrared light intensities to values on the order of 100 Tw/cm/sup 2/. Increased interest in ultraviolet lasers, for which this intensity constraint is expected to be less severe, and the entry of charged-particle drivers in the inertial confinement fusion (ICF) competition are consequences of this limitation. Analytical results based on a simple model are presented which show how the gain of an ICF target is modified by the existence of an arbitrary intensity constraint.
Date: September 13, 1979
Creator: Kidder, R.E.
System: The UNT Digital Library
Automated Electron Microprobe Identification of Minerals in Stream Sediments for the National Uranium Resources Evaluation Program. (open access)

Automated Electron Microprobe Identification of Minerals in Stream Sediments for the National Uranium Resources Evaluation Program.

This report addresses the automated electron microprobe identification of materials in stream sediments for he national uranium resources evaluation program.
Date: August 13, 1979
Creator: Mosley, W. C., Jr.
System: The UNT Digital Library
Investigation of ecosystems impacts from geothermal development in Imperial Valley, California (open access)

Investigation of ecosystems impacts from geothermal development in Imperial Valley, California

A summary of three years of field ecological investigation in Imperial Valley Environmental Program is presented. The potential terrestrial habitat impacts of geothermal development are discussed for shorebirds and waterfowl habitat, the endangered clapper rail, powerline corridors, noise effects, animal trace element burdens, and the desert community. Aquatic habitats are discussed in terms of Salton Sea salinity, effects of geothermal brine discharges to the Salton Sea, trace element baselines, and potential toxicity of brine spills in freshwater. Studies of impacts on agriculture involved brine movement in soil, release of trace metals, trace element baselines in soil and plants, water requirements of crops, and H{sub 2}S effects on crop production in the presence of CO{sub 2} and ozone.
Date: July 13, 1979
Creator: Shinn, J.H.; Ireland, R.R.; Kercher, J.R.; Koranda, J.J. & Tompkins, G.A.
System: The UNT Digital Library
Latch-up control in CMOS integrated circuits (open access)

Latch-up control in CMOS integrated circuits

The potential for latch-up, a pnpn self-sustaining low impedance state, is inherent in standard bulk CMOS-integrated circuit structures. Under normal bias, the parasitic SCR is in its blocking state but, if subjected to a large voltage spike or if exposed to an ionizing environment, triggering may occur. This may result in device burn-out or loss of state. The problem has been extensively studied for space and weapons applications. Prevention of latch-up has been achieved in conservative design (approx. 9 ..mu..m p-well depths) by the use of minority lifetime control methods such as gold doping and neutron irradiation and by modifying the base transport factor with buried layers. The push toward VLSI densities will enhance parasitic action sufficiently so that the problem will become of more universal concern. The paper will surveys latch-up control methods presently employed for weapons and space applications on present (approx. 9 ..mu..m p-well) CMOS and indicates the extent of their applicability to VLSI designs.
Date: July 13, 1979
Creator: Ochoa, A.; Dawes, W.; Estreich, D. & Packard, H.
System: The UNT Digital Library
Prospects for generating 1-10 TPa pressures with a railgun (open access)

Prospects for generating 1-10 TPa pressures with a railgun

It has been demonstrated that a plasma arc can be accelerated along two current carrying parallel rails and used to accelerate a projectile. We have performed an extensive analysis and found the task of using a railgun to accelerate an impactor plate to velocities of 10 to 40 km/s to be feasible with contemporary technology. This range of impact velocities would enable shock pressures of 1 to 10 TPa to be generated for EOS research.
Date: July 13, 1979
Creator: Hawke, R. S. & Scudder, J. K.
System: The UNT Digital Library
Fusion: the power source of the future Inertial Confinement Option (open access)

Fusion: the power source of the future Inertial Confinement Option

Among the various energy options opened to man, fusion appears particularly attractive since fuel is plentiful, cheap, and universally available, the reaction is self quenching, produces in itself no radioactive wastes and radiation hazards are minimum. However, creating on earth conditions emulating the sun is not as easy task. Two significantly different approaches to obtaining the necessary conditions are being actively pursued and both have shown encouraging progress in the past few years. Magnetic confinement will be discussed in the next paper. Inertial confinement fusion is progressing towards scientific breakeven in the 1980's. High yield targets have been successfully imploded proving the feasibility of thermonuclear burn. High densities have recently been achieved using glass lasers as drivers. Power plants using fusion sources are being studied and could become operational in the early 2000's.
Date: June 13, 1979
Creator: Rupert, V.
System: The UNT Digital Library
Transfer factors for assessing the dose from radionuclides in agricultural products (open access)

Transfer factors for assessing the dose from radionuclides in agricultural products

Transfer factors to predict the environmental transport of radionuclides through terrestrial foodchains to man were derived from the literature for radionuclides associated with the nuclear fuel cycle. We present updated transfer coefficients to predict the concentration of a radionuclide in cow's milk and other animal products and concentration factors (CF) to predict the concentration in a food or feed crop from that in soil. Where possible we note the variation of the transfer factor with physical and chemical form of the radionuclide and environmental factors, and characterize the distribution and uncertainty in the estimate. The updated transfer factors are compared with those listed in regulatory guides. The new estimates lead to recommended changes (both increases and decreases) in the listed transfer coefficients for milk and meat and to the suggested practice of adopting multiple soil-to-plant CF's that vary with the type of crop and soil in the place of a single generic CF to predict the concentration of a radionuclide in a crop from that in soil. The updated transfer factors will be useful to assess the dose from radionuclides released from nuclear facilities and evaluating compliance with regulations governing the release of radionuclides.
Date: June 13, 1979
Creator: Ng, Y.C.; Colsher, C.S. & Thompson, S.E.
System: The UNT Digital Library
Determination of absolute quantum efficiencies by photoacoustic spectroscopy (open access)

Determination of absolute quantum efficiencies by photoacoustic spectroscopy

A method is described whereby the absolute radiative quantum efficiency of paramagnetic ions in liquids or solids can be determined from photoacoustic measurements. 1 figure.
Date: April 13, 1979
Creator: Rosencwaig, A.; Weber, M. J. & Saroyan, R. A.
System: The UNT Digital Library
Ion beam production in the plasma focus device (open access)

Ion beam production in the plasma focus device

Livermore results are reviewed and compared with recent measurements of high energy ions in the plasma focus device at other laboratories. We will also discuss diagnostic techniques for measuring high energy ions including nuclear activation, particle track detectors, solid state (silicon PIN) detectors, and neutron time-of-flight measurements.
Date: April 13, 1979
Creator: Gullickson, R. L.; Pickles, W. L.; Price, D. F.; Sahlin, H. L. & Wainwright, T. E.
System: The UNT Digital Library
Photoacoustic stress (open access)

Photoacoustic stress

The theory for photoacoustic-induced stress in condensed media is developed both for near-field and far-field conditions.
Date: April 13, 1979
Creator: Rosencwaig, Allan & Scheimer, James F.
System: The UNT Digital Library
Regionalization of ground motion attenuation in the conterminous United States (open access)

Regionalization of ground motion attenuation in the conterminous United States

Attenuation results from geometric spreading and from absorption. The former is almost independent of crustal geology or physiographic region. The latter depends strongly on crustal geology and the state of the earth's upper mantle. Except for very high-frequency waves, absorption does not affect ground motion at distances less than 25 to 50 km. Thus, in the near-field zone, the attenuation in the eastern United States will be similar to that in the western United States. Most of the differences in ground motion can be accounted for by differences in attenuation caused by differences in absorption. The other important factor is that for some Western earthquakes the fault breaks the earth's surface, resulting in larger ground motion. No Eastern earthquakes are known to have broken the earth's surface by faulting. The stress drop of Eastern earthquakes may be higher than for Western earthquakes of the same seismic moment, which would affect the high-frequency spectral content. This factor is believed to be of much less significance than differences in absorption in explaining the differences in ground motion between the East and the West. 6 figures.
Date: April 13, 1979
Creator: Chung, D.H. & Bernreuter, D.L.
System: The UNT Digital Library
Rupture-safe pressure transducers (open access)

Rupture-safe pressure transducers

The design, fabrication and testing of a rupture-safe transducer for measuring gas pressures in a manned-area field environment are described. (LCL)
Date: March 13, 1979
Creator: Holten, D.C.
System: The UNT Digital Library