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A loop was operated in the Brookhaven Graphite Research Reactor to determine the effect of in-pile irradiation on the corrosion of various materials by a uranium-bismuth solution. The loop was fabricated of 2V4% chrome-1% molybdenum steel and contained, in the in-pile section, specimens of low-chrome steels, carbon steel, molybdenum, beryllium, tantalum, and graphite. The uranium-bismuth solution containing 869 ppm uranium-235, 98 ppm uranium-238, 236 ppm zirconium, and 346 ppm magnesium was circulated at 5Vi gpm. A temperature difference of 75°C was maintained on the loop. The in-pile test section ran at 500°C and the finned cooler section at 425°C. The in-pile test section was exposed to a neutron flux of 4.4 X10^^ neutrons/cm^-sec which provided a fission density of 5.5 X10" fissions/cm^-sec. Metallographic examination indicated that the corrosion and/or erosion of the steel and graphite specimens was nil. Wetting of the specimens by the uranium-bismuth solution was limited. Results indicate that in-pile and out-of-pile experimental results are similar and that fission fragment recoils did not contribute materially to either wetting or corrosion under the conditions imposed in this test.

A high-efficiency power cycle is proposed in which molecular hydrogen gas is used as a working fluid in a regenerative closed Brayton cycle. The hydrogen gas is compressed by an absorption-desorption cycle on metal hydride (FeTiH(x)) beds. Low-temperature solar or geothermal heat (temperature about 100 degrees C) is used for the compression process, and high-temperature fossil fuel or nuclear heat (temperature about 700 degrees C) supplies the expansion work in the turbine. Typically, about 90 percent of the high-temperature heat input is converted to electricity, while about 3 kilowatts of low-temperature heat is required per kilowatt of electrical output.

An equation, derived from experimental data, was developed to describe the pressure-drop-flow relationship in fixed beds of small, irregularly shaped particles. Within test limits the calculated and measured values agreed within 6%. Because this study was undertaken to solve a particular problem, it is specialized and the range of parameters is fairly restrictive. All experimental runs were made wilh beds of particles with an average particle diameter ranging from 4.8 to 45 pm and hydrogen flow rates of 3.11 x 10-3 to 1.52 x 10-1 SCFM/in.2. With one exception the bed material was deactivated FeTi 'hydride or unhydrided FeTi alloy; one run was made with S i c powder, which has approximately the same particle shape and surface characteristics as FeTi. The pressure-drop data were used in the design of a hydride reservoir to determine the spacing of porous-metal tubes which serve as particle-barrier filters in the bed.