The following quarterly report covers the period during February 16 to May 15, 1963. This report is divided into sections covering the separate activities during this period, studying the thermal behavior of the F-center in RbCl.

Introduction: "This report is an expanded version of the regular monthly letter report and is prepared in this form with the intention of reviewing work on the subject program for Euratom technical personnel. Work performed during the month of September, which normally constitutes the entire letter report, has been condensed under one heading."

The following report is the ninth in a series of monthly reports covering the program with the objective of developing alloys having superior 680 F water and/or 750 to 900 F steam corrosion resistance, as well as developing higher strength alloys for current temperature ranges while still maintaining corrosion resistance comparable to that of Zircaloy-2. This report was made covering the period December 1 to December 31, 1960.

Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. Alloys are being produced by sintering pressed powder aggregates with subsequent arc melting. Alloys have been made at two atomic percent intervals up to thirty atomic per cent carbon. In the future, higher carbon compositions are to be investigated. Techniques have been worked out for the metallographic preparation of the extremely hard and friable alloys.

The following report describes the welding characteristics of several high-strength stainless steels that were considered for use as a pressure vessel to operate at high pressures at 800 F.

Abstract: "Refinement of grain size of the base uranium-chromium eutectic alloy (uranium-5 w/o chromium) by ternary additions is discussed. Thirteen additions to the base alloy were investigated, and three additions were found to exhibit worthwhile grain-refinement tendencies. The three alloys, uranium-5 w/o chromium-0.2 w.o molybdenum, uranium-5 w/o chromium-0.2 w/o germanium, and uranium-5 w/o chromium-0.2 w/o niobium, were heat treated to produce final grain-size structures of between 0.015 and 0.033 mm."

The following report describes the charged secondary particles from all presently known decay modes of positive K mesons that have been identified, and the masses of the primaries measured by the momentum-range method.

The following document analyzes one hundred and seventy-seven bevatron tau mesons for Q value of the tau decay, tau spin and parity, and possible polarization effects.

Abstract: "Experiments were performed to characterize the types of nitro compounds that might be formed by reaction of Shell Spray Base with nitric acid, to determine the extent of their formation, if any, and their path under conditions of nitric acid recovery in the Purex Process. It is concluded that the instability of Shell Spray Base to nitration, under conditions to prevail in the plant, presents neither a disposal problem nor a safety problem."

This report examines a uranium slug that has been produced by powder metallurgical methods and exposed in the 100-DR Pile and was deformed during pile exposure.

The following report analyzes random walks and whether or not they can be used to shed any light on problems of neutron diffusion.

Abstract: "A simple solution to Saha's equation has been obtained. The method of solution involves iteration with respect to the electron pressure or concentration and can be applied to the simultaneous calculations of any number of ions. Sample results are given for lithium and aluminum."

Introduction: "Because of the importance of the value of the transport mean free path of thermal neutrons in deuterium oxide, Kash and Woods proposed to redetermine this value in deuterium oxide (99.4 atom-percent deuterium, by an extrapolation method. Kash and Woods thought that the low value of the transport mean free path might be a source of error. This paper relates studies of procedures by which (1) boron material would be dissolved in high content deuterium oxide without adding foreign atoms, particularly hydrogen atoms which might adversely affect the test, (2) the boron content of the deuterium oxide solvent may be determined, (3) ion exchangers may be deuterized and de-deuterized, and (4) ion exchange may remove specific ions from solution."

Abstract. The separation of uranyl nitrate from aqueous solutions of 0.635 M thorium nitrate, 3 M nitric acid and 3 M calcium nitrate by extraction with organic solvents has been investigated. Solvents which gave good separations were 2-tthyl hexyl acetate, ethyl benzoate, n-butyl either and beta-beta- dichloroethyl ether. In general, higher esters, ethers and alcohols are better for separating uranium from thorium that the lower homologues. Several solvents were tested at lower nitric acid concentrations. Dibutyl cellosolve gave a very good separation when the solution was 0.1 M nitric acid. Of the solvent mixtures studied that of equal parts of n-butyl ether and dibutyl cellosolve gave a good separation.

Introduction. It has been known for a long time that thorium is precipitated by oxalic acid in acid solutions, but a survey of the literature showed no study of the limits of the acidity and oxalic acid excess which yield quantitative results. V. I. Spitzin reports on the solubility of thorium oxalate in varying concentrations of several acids, but the effect of an excess oxalic acid is not included. Since solutions are sometimes presented for analysis that contain more than the recommended two per cent mineral acid, it would be advantageous to be able to quantitatively remove the thorium without otherwise altering the solutions. This was especially of interest in solutions containing bismuth, since it was hoped that some amounts of thorium could be precipitated in nitric acid solutions containing large quantities of bismuth. In removing the bismuth, first by a bismuth oxychloride precipitation, thee is every opportunity for carrying of the thorium.

Abstract. Successive approximations ae obtained from transport theory for the neutron distribution around a black sphere surrounded by a spherical gap and a non-absorbing medium extending to infinity. Six cases are calculated numerically to show the difference between this treatment and simple diffusion theory. The extrapolation distance and a quantity that is essentially the thermal utilization are calculated in different approximations. It is found that the neutron density in the gap, instead of being a constant as predicted by the simple theory, may vary by a factor of one-third in cases of practical interest.

The following report provides information conducted during histological observations made on the anatomy of female mice who have been exposed to 400 arbitrary units of slow neutrons.

This report helps determine tritium in the range of 0.1 to 100% in other gases using an ion chamber that is analyzed within this report.

Abstract: "The cross section for this reaction is calculated for three Hulthen deuteron wave functions. A hard core in the deuteron at one-half meson Compton wavelength reduces the total cross section and flattens the angular distribution in the backwards direction in agreement with experiment."

Abstract: "The distribution ratios and equilibrium constants for the extraction of zirconium and hafnium from 4 M perchloric acid with various combinations of fluorinated [beta]-diketones and organic solvents have been determined. The separation factors K'Zr/K'HF, found for this acidity were: Z-thenoyltrifluoroacetone in benzene, 25; Z-thenoyltrifluoroacetone in o-dichlorobenzene, 16; benzoyltrifluoroacetone in benzene, 18; isovaleroyltrifluoroacetone in benzene, 13; isovaleroyltrifluoroacetone in n-hexane, 13."

Introduction:"A corrosion test program in support of the Redox Project was carried out during the second quarter of 1950 to determine the corrosion rates of several austenitic stainless steels in simulated 202-B Waste Storage solution containing HF, HN03, and H2SO4 acids. The results of this program are contained herein and all original data are recorded in laboratory notebook HW-3282-T."

"Test results indicated that graphite is not suitable for seal face material. A program to evaluate various materials and seal face geometries was initiated. A seal run using nucerite-bearium combination was carried on for six hours."

This is a report of work completed during the period October 1, 1961, to December 31, 1961. The Program fuel element was completed and assembled. After extensive analysis, it was concluded that the fuel was satisfactory for use in the Program.

Nitrate contained in raffinates from Canadian Blind River mills interferes seriously with thorium extraction by secondary amines. With primary amines, however, the effect is negligible and these compounds are the preferred process extractants.