A recommended SM-1A Core I loading chart was derived from available, metallurgically acceptable elements at the SM-1A and SM-1 sites. The derivation was based on local thermal and hydraulic considerations of minimum elementto- element coolant channel clearances. These clearances were determined from field inspection measurements of outer fuel plate spacing, as modified by analytical calculations of plate ripple growth during exposure to reactor operating thermal stresses. (auth)

ABS>A series of neutron multiplication measurements made on sub-critical systems containing enriched uranium and plutonium is presented. These measurements involve both aqueous and metal systems. (auth)

Neutron resonances are analyzed numerically by determining the resonant energies, the total widths, and the neutron widths of the resonances. It was assumed that the total cross section can be represented by the sum of single- level Breit-Wigner formulas, with interference between resonance and potential scattering but no interference between resonances; that the Doppler broadening is represented by a Gaussian function; and that the instrument resolution is represented by a Gaussian function. Gauss' method was used to reduce the nonlinear problem to one in which linear methods can be applied. Some unusual techniques were used for evaluating the integrals in the function for calculating the transmission. Two programs for analyzing transmission data to obtain the parameters of the resonances were written for the IBM 7090 computer. The first program is a shape analysis for determining the resonant energies, the total widths, and the neutron widths of the resonances. This program analyzes the transmission data for as many as six resonances at once. The second program is an area analysis for determining the neutron widths of the resonances for assumed total widths. This program analyzes transmission data containing as many as 20 resonances at once. (auth)

A natural-recirculation dissolver closely approaching a stirred-tank reactor in behavior was developed, and its feasibility was demonstrated in the mercury-catalyzed dissolution of aluminum in nitric acid, It was designed to utilize the heat of reaction and evolution of gaseous reaction products for recirculation and mixing. The dissolvent was 5-molar nitric acid, containing mercury in concentrations from 10/sup -4/ to 10/sup -3/ molar as a catalyst. Dissolution rates for 1/7 scale, simulated MTR fuel elements of 2-S aluminum ranged from 0.25 to 4.0 mg/(cm/sup 2/)(rain), depending on the catalyst concentration in the dissolvent and the dissolvent flow rate. For comparable catalyst and acid feed concentrations, dissolution rates, based on unit net superficial velocities, were nearly 25 times those for dissolution of randomly- packed flat plates in a pilot plant, continuous, flooded dissolver. (auth)

The following report is the first semi-annual report of a literature survey designed to investigate the uses and technology of radioisotopes in the countries of the world from 1955 to the present. This survey includes two phases: 1) involves the direct comparison of radioisotopic work in all fields in various countries as demonstrated at international conferences. 2) involves a more detailed examination and evaluation of the individual fields of interest selected previously (Phase II is also expected to comprise the bulk of the remainder of this investigation).

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Will Wilson, regarding a legal question submitted for clarification: Waiver of salary of District Clerk when called into the Military Service.

Report describing a method for planning shutdown projects and scheduling the manpower to shut down Materials Testing Reactors (MTR) and Engineering Test Reactors (ETR).