Basic requirements for the pilot plants are that they produce a net product and that they have a potential for commercial upgrade. We have investigated a small standard mirror fusion-fission hybrid, a two-component tandem mirror hybrid, and two versions of a field-reversed mirror fusion reactor--one a steady state, single cell reactor with a neutral beam-sustained plasma, the other a moving ring field-reversed mirror where the plasma passes through a reaction chamber with no energy addition.

Aqueous waste streams from nuclear fuel processing operations may contain trace quantities of heavy metals such as uranium. Conventional chemical and physical treatment may be ineffective or very expensive when uranium concentrations in the range of 10 to 100 g/m/sup 3/ must be reduced to 1 g/m/sup 3/ or less. The ability of some microorganisms to adsorb or complex dissolved heavy metals offers an alternative treatment method. Uranium uptake by Saccharomyces cerevisiae NRRL Y-2574 and a strain of Pseudomonas aeruginosa was examined to identify factors which might affect a process for the removal of uranium from wastewater streams. At uranium concentrations in the range of 10 to 500 g/m/sup 3/, where the binding capacity of the biomass was not exceeded, temperature, pH, and initial uranium concentration were found to influence the rate of uranium uptake, but not the soluble uranium concentration at equilibrium. 6 figs.

The ETOE-2/MC/sup 2/-2/SDX multigroup cross-section processing codes were designed to provide a comprehensive neutron cross-section processing capability for a wide range of applications including critical experiment analysis and core design calculations. Fundamental nuclear data from ENDF/B provide the primary input to the code system, and the output consists of a user-specified CCCC ISOTXS multigroup cross-section data file. Great flexibility is provided to the user in specifying the rigor of the calculation, so that a unified cross-section processing system with a single data base which may be used for both preliminary survey scoping studies and rigorous design calculations is available. The principal program blocks of the code system include a library processor and format converter between ENDF/B data and the MC/sup 2/-2/SDX library; an ultra-fine-group fundamental-mode calculation (MC/sup 2/-2) which provides a composition-dependent spectrum calculation and broad-group collapsing capability; a rigorous hyper-fine-group, spatially hetegeneous resolved resonance calculation (RABANL) to supplement the more approximate NR approximation used in the ultra-fine-group treatment; and an intermediate group space-dependent capability (SDX). 5 figures, 4 tables.

Investigation of about 1,600 mines and prospects for perennial discharge resulted in the measurement of temperature, pH, specific conductance, and discharge at 80 sites to provide information for a geothermal data base. Measurements were made in the fall, winter, and late spring or early summer to provide information about seasonal variability. None of the temperatures measured exceeded the mean annual air temperature by 15/sup 0/F, but three areas were noted where discharges were anomalously warm, based upon high temperatures, slight temperature variation, and quantity of discharge. The most promising area, at the Gold Bug mine in the Little Rockies, discharges water averaging 7.3/sup 0/C (12.1/sup 0/F) above the mean annual air temperature. The discharge may represent water heated during circulation within the syenite intrusive body. If the syenite is enriched in uranium and thorium, an abnormal amount of heat would be produced by radioactive decay. Alternatively, the water may move through deep permeable sedimentary strata, such as the Madison Group, and be discharged to the surface through fractures in the pluton.

By irradiating cells attached to thin Mylar foils with diatomic deuteron beams, the role of interaction distance in radiobiology can be investigated in a unique manner. The molecule breaks up into two separate ions which diverge from each other because of the multiple scattering process in the foil and in the cellular material. A distribution of separation distances results whose characteristic separation depends on the Mylar foil thickness. An experimental facility to use diatomic beams is described. Cell survival results for V79 Chinese hamster cells synchronized in late S phase show that damage does result from tracks separated by as much as 250 nm. However, damage also results from interaction at nanometer dimensions.

The goal of TVA's Availability Improvement Program for its fossil-fueled power plants is to increase plant availability from 79 to 83%, to reduce the forced outage rate from 10 to 7%, and to reduce the equivalent outage rate related to forced deratings from 6 to 2%. As background for this program historical data on plant availabilities, trends toward improved availability, factors which contribute to current reliability, and ongoing programs to improve fossil-fueled plant reliability are discussed. (LCL)

Experimental and theoretical studies have been performed to characterize the behavior of airborne particulates (aerosols) expected to be produced by hypothetical core disassembly accidents (HCDA's) in liquid metal fast breeder reactors (LMFBR's). These aerosol studies include work on aerosol transport in a 20-m high, 850-m/sup 3/ closed vessel at moderate concentrations; aerosol transport in a small vessel under conditions of high concentration (approx. 1000 g/m/sup 3/), high turbulence, and high temperature (approx. 2000/sup 0/C); and aerosol transport through various leak paths. These studies have shown that little, if any, airborne debris from LMFBR HCDA's would reach the atmosphere exterior to an intact reactor containment building.

Typological and geographic analyses indicate that Tell el Yahudiyeh ware (found in Cyprus, Egypt, Nubia, and the Levant during the Middle Bronze period, c. 1750-1550 B.C.) were probably manufactured in two areas, the Nile Valley and the Levant. Activation analysis was carried out and correlated with the archaeological analyses. Results confirm the two "families" of the ware, one Egyptian and one Levantine. Speculations are offered on the social interaction of the period. 11 figures, 2 tables. (DLC)