The computer control system used on the twelve Neutral Beams of the 2XIIB experiment at the Lawrence Livermore Laboratory (LLL) has evolved over the last three years. It is now in its final form and in regular use. It provides automatic data collection, reduction, and graphics presentation, as well as automatic conditioning, automatic normal operation, and processing of calorimeter data. This paper presents an overview of the capabilities and implementation of the current system, a detailed discussion of the automatic conditioning algorithm, and discusses the future directions for neutral beam automation.

Four manuals containing methods for the accountability of plutonium nitrate solutions, plutonium dioxide, uranium dioxide and mixed uranium-plutonium oxide have been prepared by us and issued by the U.S. Nuclear Regulatory Commission. A similar manual on methods for the accountability of uranium and plutonium in reprocessing plant dissolver solutions is now in preparation. In the present paper, we discuss the contents of the previously issued manuals and give a preview of the manual now being prepared.

A numerical analysis has been performed on the time-dependent equations of heat balance, gas convection, pressure drop, and mass-flow rate for supercritical helium gas flowing through a tubular superconductor. Three dimensional graphs of wall temperature, gas temperature, and mass-flow rate as functions of position and time are used to show the evolution of normal zones. In contrast to other methods of studying stability in superconductors by a quasi-steady-state analysis of critical-sized normal zones (minimum propagating zone), our analysis shows that stability is influenced by both the magnitude and the time dependence of the disturbance. As the current is increased in a system subjected to certain types of thermal disturbances, propagating normal zones may originate at positions well downstream from the site of the disturbance. At higher currents, propagating zones may originate both downstream and at the disturbed site, coalescing into a large propagating normal zone. With certain types of disturbances (such as an extraneous heat source over a short length of conductor), higher critical currents may be reached by fast current ramping, while with other types of disturbances (such as self heating in a degraded section of conductor), slow current ramping leads to higher critical currents.

Bronze-processed Nb/sub 3/Sn composite wire conductors exhibit changes in their superconducting parameters when strained in tension. This paper describes a detailed study of the effect of strain on critical current and an analysis by optical and SEM techniques of crack formation in the Nb/sub 3/Sn layer under strain. The effect of strain history on both reversible and irreversible changes in critical current and the roles of differential thermal contraction induced residual strains and of Nb/sub 3/Sn cracking are discussed.

In analyzing CaF/sub 2/:Dy (TLD-200) data from the environmental monitoring program at the Lawrence Livermore Laboratory, a quantity of significance is the dose to the thermoluminescence dosimeters during shielded storage. This paper describes a method for determining this shield dose, which can then be related to the dose from cosmic radiation. Data, based on quarterly TLD exposure periods, show a range of 43-56 ..mu..rads per day in a 75 mm thick lead shield. Observed variations in the shield dose have led to studies of prolonged exposure of TLDs to elevated and reduced temperatures typical of those in the Livermore Valley.

The Lawrence Livermore Laboratory (LLL) is currently in the construction stage of the Mirror Fusion Test Facility (MFTF). MFTF will be the next large mirror fusion experiment and employs a large set of superconducting Yin-Yang coils. These coils contain 54,430 kg of stabilized NbTi conductor and will generate a peak field of 7.68 T with a stored energy of 409 MJ. This paper presents details of the design of these coils and the status of the fabrication.

Appropriate treatment for internal depositions of some radionuclides can reduce the radiation doses by as much as factors of two to ten. While at first thought that may seem a relatively small therapeutic effect, it is a useful gain for the patient in reducing the dose and may be a significant help in preventing late effects from the radiation. The list of important available treatments include agents that reduce gastrointestinal absorption, blocking and diluting compounds, mobilizing agents, and chelating drugs. Wound irrigation or excision and lung lavage are mechanical techniques that can reduce radionuclide depositions. Successful treatment depends on early application of these drugs and techniques following exposure. This must be done usually on the basis of very limited exposure information, which emphasizes the need for preplanning the medical emergency program if internal radioactive contamination is possible. In most cases, the risks of treatment are well identified. Since the exposure risks are often poorly understood when the decision for treatment must be made, the omission of treatment can be more serious than proceeding with a low or no risk therapeutic regimen.