The distribution of fuel elements in the EBWR core is described. Spike elements with boron steel strips were provided in the core for burnup allowance. A calibration of the control rod system with Zircaloy followers was made. Void coefficient measurements were made for two different H/sub 3/BO/sub 3/ concentrations. Power runs were made, and reactivity loss vs. power characteristic was obtained. Steam remaining in the core, or carryunder,'' was indicated. Some of the spikes were removed for increasing the power to 80 Mw. Calculations were made of the reactivity loss with coolant void and of the average void vs. reactor power. (D. L.C.)

Over the past few years we have developed a system which allows several different liquid hydrogen and liquid deuterium targets to be placed in the electron beam of the Stanford Mark III accelerator and which can be operated from a remote position. The geometry of our scattering chamber requires that the motion (of the various targets into position) must be in the vertical direction, but that the overall height of the system be constant. These requirements are met by using an internal retractable bellows arrangement to raise and lower the target cells. As many as five cells can be used in conjunction with a single reservoir system.

From 19th International Union of Pure and Applied Chemistry Congress, London. A systematic introduction is presented to the subject of the variation with pH of the polarographic half-wave potential, which is probably the most readily measured electrochemical energetic parameter of organic compounds. Emphasis is placed on (a) the types of relationships observed for both reversible and irreversible electrode processes, (b) the mathematical formulation of these relationships, (c) the structural, mechanistic, kinetic, and environmental factors influencing such relationships, and (d) the presumptive physical causes for such relationships, e.g., the effect of pH on the electrochemical kinetics. Although the discussion is primarily concerned with behavior in aqueous solution, the conclusions drawn are equally valid for nonaqueous media in which hydrogen ion or some other Lewis acid can play a significant role. The half-wave potential for an organic electrode process may be independent of pH, or may vary lineanly or sigmoidally; other types of relationships observed are likely to be combinations of such effects. These variations may be due (a) to direct participation of hydrogen ion in the transition state involving the electroactive site in the organic molecule and the electron source, e.g., polarization of the bond to be broken, (b) to control …

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In contrast to the miscibility gap previously reported for the system HfC-UC, complete solid solubility of these carbides at 2000 c- C was demonstrated. Included are the preparation, heating conditions, x-ray data, and chemical analysis of the starting materials and the solid solutions. (P.C.H.)