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Free-surface velocity measurements of plates driven by reacting and detonating RX-03-BB and PBX-0404 (open access)

Free-surface velocity measurements of plates driven by reacting and detonating RX-03-BB and PBX-0404

Copper plates 90 mm in diameter, of thickness 0.25 mm and 0.5 mm, were accelerated by an adjacent 17 mm thick cylinder of RX-03-BB or PBX-9404-03. The explosive was initiated by impact of a thick flyer from the LLNL 102 mm gun, providing either a reactive or fully detonating wave, by appropriate choice of flyer velocities up to 1.30 mm/..mu..s. The free surface velocity of the plates were measured with a Fabry-Perot velocimeter. Excellent experimental free-surface velocity histories have been obtained. Calculations of this history employing beta-burn and nucleation and growth high explosives models are in good agreement with fully detonating experiments. For reacting RX-03-BB, adjustments in the parameter are needed. The experimental technique gives records whose agreement with calculation is sensitive to the model and is therefore a good way of testing new high explosive models. Also, this method allows one to infer information about the reaction zone length.
Date: July 13, 1981
Creator: Erickson, L. M.; Palmer, H. G.; Parker, N. L. & Vantine, H. C.
System: The UNT Digital Library
Progress in the tandem mirror program (open access)

Progress in the tandem mirror program

Experimental results in TMX have confirmed the basic principles of the tandem-mirror concept. A center-cell particle confinement parameter eta tau approx. 10/sup 11/ cm/sup -3/ s has been obtained at ion temperatures around 100 eV, which is a hundred-fold improvement over single mirrors at the same temperatures. For TMX these results have been obtained at peak beta values in the center cell in the range 10 to 40%, not yet limited by MHD activity; and ion-cyclotron resonant heating (ICRH) in the Phaedrus tandem-mirror experiment has produced beta values approx. 25%, which is several times the ideal MHD limit for that device. In addition, it has been demonstrated that the end fan chambers of TMX simultaneously isolate the hot electrons from the end walls, provide adequate pumping and conveniently dispose of the exhaust plasma energy either by thermal deposition on the end wall or by direct conversion to electricity (at 48% efficiency in agreement with calculations). Also, evidence was obtained for inherent divertor action in TMX, presumably in part responsible for the observed low impurity level (<0.5% low-Z ions in the center cell).
Date: September 13, 1981
Creator: Fowler, T.K. & Borchers, R.R.
System: The UNT Digital Library
Diagnostic timing system for the TMX-Upgrade (open access)

Diagnostic timing system for the TMX-Upgrade

This system provides trigger signals at various times and clock signals at various frequencies for the CAMAC transient recorders of the plasma diagnostics system for the TMX-Upgrade. The timing system is designed so that all clocks are in fixed-phase relation to their corresponding triggers and to each other. Therefore, data recorded from the different diagnostics can be directly time compared. Trigger signals can be generated in 100-ns increments, with an uncertainty of 500 ps. The clock signals have a time uncertainty of less than 1 ns. The system is arranged so that these accuracies are maintained over the entire diagnostic room. The timing system is modular and uses mostly digital delay generators, signal fan outs, and frequency dividers. Because of the modular approach, the system can be arranged in several ways (producing many possible trigger times and sample rate clocks) and still maintain a system in which all clocks and triggers are in a fixed-phase relationship.
Date: October 13, 1981
Creator: Bell, H.H. Jr.; G.W., Coutts & Hinz, A.F.
System: The UNT Digital Library
Immobilization of high level nuclear reactor wastes in SYNROC: a current appraisal. [Synthetic perovskite and hollandite; natural zirconolite and perovskite] (open access)

Immobilization of high level nuclear reactor wastes in SYNROC: a current appraisal. [Synthetic perovskite and hollandite; natural zirconolite and perovskite]

Results are presented for leach testing at 95/sup 0/C and 200/sup 0/C of SYNROC containing 9% and 20% simulated high level radioactive waste, synthetic hollandite and pervoskite samples, and natural zirconolite and pervoskite samples. Single phase synthetic minerals show much higher leach rates than natural mineral samples and polyphase SYNROC samples. Natural zirconolite samples with low radiation damage have leach rates at 200/sup 0/C based on U which are identical to those measured on SYNROC samples. Natural zirconolites with very large accumulated ..cap alpha.. dose and radiation damage have leach rates at 200/sup 0/C which are only 5 times higher than those of low dose samples.
Date: October 13, 1981
Creator: Oversby, V.M. & Ringwood, A.E.
System: The UNT Digital Library
Holdup measurement for nuclear fuel manufacturing plants (open access)

Holdup measurement for nuclear fuel manufacturing plants

The assay of nuclear material holdup in fuel manufacturing plants is a laborious but often necessary part of completing the material balance. A range of instruments, standards, and a methodology for assaying holdup has been developed. The objectives of holdup measurement are ascertaining the amount, distribution, and how firmly fixed the SNM is. The purposes are reconciliation of material unbalance during or after a manufacturing campaign or plant decommissioning, to decide security requirements, or whether further recovery efforts are justified.
Date: July 13, 1981
Creator: Zucker, M.S.; Degen, M.; Cohen, I.; Gody, A.; Summers, R.; Bisset, P. et al.
System: The UNT Digital Library