Effects of low-temperature fusion neutron irradiation on critical properties of a monofilament niobium-tin superconductor (open access)

Effects of low-temperature fusion neutron irradiation on critical properties of a monofilament niobium-tin superconductor

The objective of this work was to irradiate a Nb/sub 3/Sn superconductor with 14.8 MeV neutrons at 4 K and measure critical current in transverse fields of up to 12 T, irradiating up to a fluence sufficient to decrease the critical current to below its initial value. Critical temperatures were also to be measured. The samples were to be kept near 4 K between the irradiation and the measurement of critical properties. This work is directed toward establishing an engineering design fluence limit for Nb/sub 3/Sn when used in fusion reactor superconducting magnets.
Date: March 22, 1984
Creator: Guinan, M.W.; Van Konynenburg, R.A. & Mitchell, J.B.
Object Type: Report
System: The UNT Digital Library
Recent US target-physics-related research in heavy-ion inertial fusion: simulations for tamped targets and for disk experiments in accelerator test facilities (open access)

Recent US target-physics-related research in heavy-ion inertial fusion: simulations for tamped targets and for disk experiments in accelerator test facilities

Calculations suggest that experiments relating to disk heating, as well as beam deposition, focusing and transport can be performed within the context of current design proposals for accelerator test-facilities. Since the test-facilities have lower ion kinetic energy and beam pulse power as compared to reactor drivers, we achieve high-beam intensities at the focal spot by using short focal distance and properly designed beam optics. In this regard, the low beam emittance of suggested multi-beam designs are very useful. Possibly even higher focal spot brightness could be obtained by plasma lenses which involve external fields on the beam which is stripped to a higher charge state by passing through a plasma cell. Preliminary results suggest that intensities approx. 10/sup 13/ - 10/sup 14/ W/cm/sup 2/ are achievable. Given these intensities, deposition experiments with heating of disks to greater than a million degrees Kelvin (100 eV) are expected.
Date: March 22, 1982
Creator: Mark, J.W.K.
Object Type: Article
System: The UNT Digital Library
SSC tunnel air conditioning (heating/cooling and dehumidifying) (open access)

SSC tunnel air conditioning (heating/cooling and dehumidifying)

The great distances between penetrations to the SSC tunnel create difficulties in ventilating and air conditioning the tunnel. Major penetrations were assumed for these calculations to be 8000 meters apart (one per sector) into an 8 foot diameter tunnel. The result of this large length to diameter ratio is that one cannot heat or dehumidify only from one end of the sector. Increasing the tunnel diameter to 9 feet does not affect this study; the area actually available for air flow depends on the floor design and space taken up by magnets and other equipment. For the 8 foot diameter tunnel this air flow area is taken to be 50 ft/sup 2/, the full tunnel cross sectional area. The length of the tunnel results in the necessity for distributed heating and dehumidification in the tunnel. Equipment may provide sufficient heating during operations, but there are some uncertainties. Among these are rock thermal conductivity. There must be introduction of outside air and removal of tunnel air. Skidded air intake units sized for 1 mph of tunnel air flow, consuming about 100 kW each, can provide outside air during construction, when circulation of air is not possible, and during operation.
Date: March 22, 1985
Creator: Peterson, T. & Theilacker, J.
Object Type: Report
System: The UNT Digital Library
Environmental radiological studies downstream from Rancho Seco Nuclear Power Generating Station (open access)

Environmental radiological studies downstream from Rancho Seco Nuclear Power Generating Station

This report summarizes the information compiled in 1984 while assessing the environmental impact of radionuclides in aquatic releases from the Rancho Seco Nuclear Power Generating Station. Gamma-emitting radionuclides discharged since 1981 are found in many of the dietary components derived from the creeks receiving the effluent wastewater. Some soils and crops are found to contain radionuclides that originate from the contaminated water that was transferred to land during the irrigation season. /sup 134/Cs and /sup 137/Cs are the primary gamma-emitting radionuclides detected in the edible flesh of fish from the creeks. Concentrations in the flesh of fish decreased exponentially with distance from the plant. No significant differences in the /sup 137/Cs activity were found between male and female fish of equal size, but concentrations may vary in fish of different size, with the season and diet. 21% of the total /sup 137/Cs and /sup 134/Cs discharged between 1981 and 1984 is associated with the creek sediments to a distance of 27 km from the plant. Fractions of the missing inventory have been transferred to land during the irrigation season or to downstream regions more distant than 27 km from the plant. The radiocesium content of the sediments in 1984 decreased …
Date: March 22, 1985
Creator: Noshkin, V. E.; Wong, K. M.; Eagle, R. J.; Dawson, J. W.; Brunk, J. L. & Jokela, T. A.
Object Type: Report
System: The UNT Digital Library
Observations of parametric instabilities in long-scalelength plasmas (open access)

Observations of parametric instabilities in long-scalelength plasmas

This paper is organized in the following manner. In the second section we discussed absorption; the dependence of scattered light signatures of parametric instabilities occurring at n/sub e/ less than or equal to n/sub c//4 on corona size is shown in section three; and evidence for suprathermal electron production in these long-scale length plasmas is presented in section four. The results and conclusions are finally summarized in section five.
Date: March 22, 1983
Creator: Campbell, E. M.; Max, C. E.; Phillion, D. W.; Turner, R. E.; Estabrooke, K.; Laskinski, B. et al.
Object Type: Article
System: The UNT Digital Library
The effects of furnace environment on the mechanical properties of vanadium (open access)

The effects of furnace environment on the mechanical properties of vanadium

We have conducted tests to ascertain whether or not exposure to erbia would adversely affect the mechanical properties of vanadium more than the regular annealing furnace environment. Mechanical properties of the vanadium exposed to erbia are not different from those of the vanadium to a regular annealing furnace environment. However, there is a change in the impurity levels, the carbon content increasing and the oxygen content decreasing. There is also anomalous behavior in the strain-hardening and elongation to failure of both the annealed and the erbia specimens. It is possible that hydrogen could have been released as a result of water reacting with the vanadium to form oxides. Very small amounts of hydrogen can impair the mechanical properties of vanadium. It is possible, on the basis of diffusion data, that, should hydrogen be generated in this fashion, it could diffuse completely through the vanadium and contaminate whatever is in contact with the vanadium. Further experiments should be conducted to verify whether or not hydrogen is in fact responsible for the anomalous strain-hardening and elongation-to-failure behavior. 20 refs., 8 figs., 3 tabs.
Date: March 22, 1988
Creator: dePruneda, J. H.; Gallegos, G. F. & Stratman, M. P.
Object Type: Report
System: The UNT Digital Library
Nonlinear materials for frequency conversion (open access)

Nonlinear materials for frequency conversion

Two figures of merit, the threshold power (P/sub th/) and the limiting volume (V/sub min/) can be used to compare the relative efficiency and economy of new harmonic generating crystals. The properties of barium metaborate and L-Arginine phosphate are used to illustrate the effect of nonlinearity, birefringence, and damage threshold on these figures of merit.
Date: March 22, 1988
Creator: Velsko, S. P. & Eimerl, D.
Object Type: Article
System: The UNT Digital Library
Magnetic switching, final chapter, Book I: the ATA upgrade prototype (open access)

Magnetic switching, final chapter, Book I: the ATA upgrade prototype

Efforts directed at finding a 10 kHz switch to replace the current 1 kHz gas blown spark gap have culminated in a prototype for an upgrade of ATA. The design and performance of this prototype as well as possible options and recommendations concerning an eventual upgrade are described. 4 references, 9 figures.
Date: March 22, 1983
Creator: Birx, D.; Cook, E.; Hawkins, S.; Poor, S.; Reginato, L.; Schmidt, J. et al.
Object Type: Article
System: The UNT Digital Library
Lawrence Livermore National Laboratory search and property protection programs -- March 22, 1984 (open access)

Lawrence Livermore National Laboratory search and property protection programs -- March 22, 1984

On November 30, 1983, the LLNL Directorate met to discuss Laboratory policy regarding searches. An advance package (dated November 16, 1983) discussing background issues and DOE`s property protection and safeguards concerns was distributed to the Director and Associate Directors. A number of Associate Directors expressed concern about the nature of the theft problem at the Laboratory. There was also discussion about many employees` perception that Laboratory Management (including the Security Department) really did not care. The Director endorsed the need to establish searches in the SNM areas. The property protection type of searches were perceived as being very sensitive from a labor relations perspective. Nevertheless, the Directorate was sufficiently concerned about the safeguards and property protection issues to request the Security Department to develop a search plan for their review. A draft Search Program was prepared by the Security Department and reviewed individually with the Directorate for their comments. On March 19, 1984, the Directorate met collectively to consider a summary of these individual comments and to finalize a Search Program. Decisions made during that meeting have been incorporated into this document. This plan describes the search procedures that will be implemented at SNM areas and a two point program …
Date: March 22, 1984
Creator: Leary, D.A.
Object Type: Report
System: The UNT Digital Library