In studies of the fabrication of fuel subassemblies for the supercritical-water reactor, the limited ductility of stainless steel-UO₂ fuel sheet made the fabrication of corrugated-flat-plate-type subassemblies impractical. A fabricable MTR-type assembly, 5/8 in. square and 30 in. long, was developed. Methods for edge cladding fuel sheet were developed and a brazing alloy, GE-75, was found to be corrosion resistant in supercritical water.

Abstract: "Small amounts of acetic acid, equivalent to 400 ul. of 0.3 to 0.13 g/L. can be titrated coulonatrically in the presence of a 10 to 25-fold excess of HN03 in 70%, isopropanol. An accuracy of +/- 0.1% and a precision of +/- 8.5% (99% limite) are obtained.

"Time of flight spectrometers for the study of neutrons emitted in charged particle reactions have become important in recent years, following the development of suitable photomultiplier tubes and electronic circuits for nanosecond (ns) timing measurements. The principle of operation is simple. The particles exciting the nuclear reactions in which the neutrons are produced fall on the target in bunches of the order of a nanosecond in width. the arrival of product neutrons at a organic scintillation counter (proton recoil) detector placed a few meters from the target gives signals which can be used to determine the flight time of the neutrons from target to detector. A time-reference pule corresponding to the arrival of beam pulses at the target is required."

The flux standard is a device which will give a known flux-linkage change to be used as a calibration. At the Radiation Laboratory, two types of flux standards are used, a stationary type and a portable type.

Abstract. Some diffusion parameters of water are computed with various thermal-neutron scattering laws. It is found that the diffusion cooling coefficient, in particular, is reasonably sensitive to the scattering law, but that the diffusion cooling coefficients predicted by the Radkowsky and Nelkin kernels are in fortuitious agreement. The coefficients computed for the Nelkin kernel, when treated in a manner consistent with the way in which experimental data are treated, are in reasonable agreement with the results of a recent experiment.

Abstract. Recently (CP-1989) it has been shown that the neutron density, and thus the heat production, at the end of a slug with an A1 cap may be appreciably higher than that at the middle of the slag. A re-examination of earlier temperature calculations is made in light of this effect.

This is a report of what may be an invention in a process or processes for preparing roughly spherical uranium metal particles suitable for use in matrix type nuclear reactor fuel elements.

A method of performing a series of solvent extractions using a minimum of pulse generators is briefly outlined.