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Inertial-confinement-fusion targets (open access)

Inertial-confinement-fusion targets

Inertial confinement fusion (ICF) targets are made as simple flat discs, as hollow shells or as complicated multilayer structures. Many techniques have been devised for producing the targets. Glass and metal shells are made by using drop and bubble techniques. Solid hydrogen shells are also produced by adapting old methods to the solution of modern problems. Some of these techniques, problems and solutions are discussed. In addition, the applications of many of the techniques to fabrication of ICF targets is presented.
Date: November 16, 1981
Creator: Hendricks, C.D.
System: The UNT Digital Library
Projections of transport scaling laws for small toroidal reactors (open access)

Projections of transport scaling laws for small toroidal reactors

Transport in present day Spheromaks is dominated by impurity radiation. Fortunately, this is largely from oxygen and carbon, not metal vapor from the walls of the vessel on plasma guns and it is expected this loss can be eliminated by improved technique. The formation and gross MHD stability properties of these plasmas are quite well understood and so the reactor predictions depend on estimates of the energy loss rates from the plasma. In the absence of significant experimental data one is driven to consider other related devices. Tokamaks show classical ion transport, scaling with 1/B/sup 2/, but anomalous electron transport which is very insensitive to magnetic field, the well known Alcator scaling. The scaling of the Spheromak to a reactor size still produces favorable Q values with these pessimistic results. The reactor is small, with power output in the 10 to 50 MW range, but this could be deployed as a multiple unit power station, with good reliability due to the duplication, or as a small power unit for a ship or remote site. It also makes an attractive test reactor for the near term.
Date: November 16, 1981
Creator: McNamara, B.
System: The UNT Digital Library
Design and test of low-capacitance, air-insulated, 80-kV, 0. 5-sec source cables for MFTF sustaining-neutral-beam power supples (open access)

Design and test of low-capacitance, air-insulated, 80-kV, 0. 5-sec source cables for MFTF sustaining-neutral-beam power supples

The design of air-insulated cables, which meet strict requirements, is described. Inductance, heat transfer, and electrostatic computer codes are used in design. Tests include electric circiut parameters, dc voltage holdoff, impulse voltage holdoff, heat rise at greater than peak duty, and shield mechanical strength.
Date: October 16, 1981
Creator: Mayhall, D. J.; Wilson, J. H.; Caldwell, W. J.; Watson, T. F. & Jenkins Jr., J. W.
System: The UNT Digital Library
Inspection methods for safeguards systems at nuclear facilities (open access)

Inspection methods for safeguards systems at nuclear facilities

A project team at Lawrence Livermore National Laboratory has been developing inspection procedures and training materials for the NRC inspectors of safeguards systems at licensed nuclear facilities. This paper describes (1) procedures developed for inspecting for compliance with the Code of Federal Regulations, (2) training materials for safeguards inspectors on technical topics related to safeguards systems, such as computer surety, alarm systems, sampling techniques, and power supplies, and (3) an inspector-oriented methodology for evaluating the overall effectiveness of safeguards systems.
Date: October 16, 1981
Creator: Minichino, C. & Richard, E.W.
System: The UNT Digital Library
Resistance-driven bunching mode of an accelerated ion pulse (open access)

Resistance-driven bunching mode of an accelerated ion pulse

Amplification of a longitudinal perturbation of an ion pulse in a linear induction accelerator is calculated. The simplified accelerator model consists only of an applied field (E/sub a/), distributed gap impedance per meter (R) and beam-pipe capacity per meter (C). The beam is treated as a cold, one-dimensional fluid. It is found that normal mode frequencies are nearly real, with only a very small damping rate proportional to R. This result is valid for a general current profile and is not restricted to small R. However, the mode structure exhibits spatial amplification from pulse head to tail by the factor exp(RCLv/sub o//2), where L is pulse length and v/sub 0/ is drift velocity. This factor is very large for typical HIF parameters. An initially small disturbance, when expanded in terms of the normal modes, is found to oscillate with maximum amplitude proportional to the amplification factor.
Date: October 16, 1981
Creator: Lee, Edward P.
System: The UNT Digital Library
Surveillance dosimetry of operating power plants (open access)

Surveillance dosimetry of operating power plants

The main focus of the research efforts presently underway is the LWR power reactor surveillance program in which metallurgical test specimens of the reactor PV and dosimetry sensors are placed in three or more surveillance capsules at or near the reactor PV inner wall. They are then irradiated in a temperature and neutron flux-spectrum environment as similar as possible to the PV itself for periods of about 1.5 to 15 effective full-power years (EFPY), with removal of the last capsule at a fluence corresponding to the 30- to 40-year plant end-of-life (EOL) fluence. Because the neutron flux level at the surveillance position is greater than at the vessel, the test is accelerated wit respect to the vessel exposure, allowing early assessment of EOL conditions.
Date: October 16, 1981
Creator: McElroy, W.N.; Davis, A.I. & Gold, R.
System: The UNT Digital Library
SYNROC C: preparation and radwaste distribution (open access)

SYNROC C: preparation and radwaste distribution

Results of the synthesis of SYNROC C from both high surface area (16m/sup 2//g) and low surface area (4m/sup 2//g) powders at low and high oxygen fugacities indicate variations in radionuclide distribution. These results are most striking for the partitioning of uranium between perovskite and zirconolite. In highly active powders, the formation of a pyrochlore precursor ensures that equilibrium partitioning is approached. In less active powders, no low temperature pyrochlore is formed. As a result, the uranium partitioning is a function of nucleation processes. At high oxygen fugacities, uranium is rejected from perovskite and an additional uranium rich phase is formed precluding the synthesis of SYNROC C in air.
Date: October 16, 1981
Creator: Ryerson, F. J.; Hoenig, C. L. & Smith, G. S.
System: The UNT Digital Library
Improving the bulk laser-damage resistance of KDP by baking and pulsed-laser irradiation (open access)

Improving the bulk laser-damage resistance of KDP by baking and pulsed-laser irradiation

Isolated bulk damage centers are produced when KDP crystals are irradiated by 1-ns 1064-nm pulses. We have tested about 100 samples and find the median threshold to be 7 J/cm/sup 2/ when the samples are irradiated only once at each test volume (1-on-1 tests). The median threshold increased to 11 J/cm/sup 2/ when the test volumes were first subjected to subthreshold laser irradiation (n-on-1 tests). We baked several crystals at temperatures from 110 to 165/sup 0/C and remeasured their thresholds. Baking increased thresholds in some crystals, but did not change thresholds of others. The median threshold of baked crystals ranged from 8 to 10 J/cm/sup 2/ depending on the baking temperature. In crystals that had been baked, subthreshold irradiation produced a large change in the bulk damage threshold, and reduced the volume density of damage centers relative to the density observed in unbaked crystals. The data are summarized in the table.
Date: September 16, 1981
Creator: Swain, J.E.; Stokowski, S.E.; Milam, D. & Rainer, F.
System: The UNT Digital Library
Breeder reactor fuel fabrication system development (open access)

Breeder reactor fuel fabrication system development

Significant progress has been made in the design and development of remotely operated breeder reactor fuel fabrication and support systems (e.g., analytical chemistry). These activities are focused by the Secure Automated Fabrication (SAF) Program sponsored by the Department of Energy to provide: a reliable supply of fuel pins to support US liquid metal cooled breeder reactors and at the same time demonstrate the fabrication of mixed uranium/plutonium fuel by remotely operated and automated methods.
Date: July 16, 1981
Creator: Bennett, D.W.; Fritz, R.L.; McLemore, D.R. & Yatabe, J.M.
System: The UNT Digital Library
Design of neutron streak camera for fusion diagnostics (open access)

Design of neutron streak camera for fusion diagnostics

In laser fusion, such as with the NOVA under construction at the Lawrence Livermore National Laboratory, the D-T reaction is expected to be complete within 100 ps. It is important to measure the time-dependence of the neutron flux from the fusion target. We describe the design of a new neutron detector of 20 ps resolving time that can be used to study the history of fusion burn.
Date: June 16, 1981
Creator: Wang, C. L.; Kalibjian, R. & Singh, M. S.
System: The UNT Digital Library
Hyper-filter-fluorescer spectrometer for fusion x-ray diagnostics (open access)

Hyper-filter-fluorescer spectrometer for fusion x-ray diagnostics

The filter-fluorescer spectrometer (FFS) is a powerful tool for measuring x-ray spectrum from high fluence x-ray sources. However, this technique is limited to energies less than 120 keV, because there are no practical absorption edges available above this energy. In this paper, we present a new method of utilizing the filter-fluorescer system for x-ray spectral measurement above 120 keV. The new apparatus is called hyper-filter-fluorescer spectrometer (HFFS).
Date: June 16, 1981
Creator: Wang, C. L.
System: The UNT Digital Library