Quarterly progress report on Accurate Nuclear Fuel Burnup Analysis project.

Abstract: The rate of extraction of PuIV in either direction between benzene-TTA and aqueous HNO3 solutions is shown in the present study to be fast enough so that application of the chelate process to continuous operation should be feasible. This conclusion is based on two primary considerations: 1. The mechanism limiting the rate of extraction appears to be diffusion and not chemical-reaction-limiting. 2. The extraction may be controlled by adjustment of the system conditions to give almost any desired specifications of rate and/or equilibrium. A continuous process involving multiple extraction stages with a controlled pH gradient is proposed for obtaining maximum decontamination and plutonium recovery.

Introduction: "A number of determination have been made of the half life of polonium-210 by calorimetry. Counting affords an entirely different method of determining half lives and requires only a small amount of activity. Therefore for comparison a half-life determination by counting was undertaken with a sample of approximately 0.5 millicurie of polonium."

Fused uranium dioxide was separated into fractions of varying particle size by air separation. Specimens of the nominal size of 1/8 by 1/4 by 1½ in. were formed by hydrostatic pressing, firing, and lapping. Specimens prepared from the 0 to 5 μ fraction were the strongest and most dense. The room-temperature density was about 92% of theoretical and the room-temperature flexural strength was about 12,000 1b. per sq. in. When tested at 1000°C., the strength was about 18,000 1b. per sq. in. The flexural strength of specimens decreased and their density decreased as the starting particle size was increased. The crystallization of the urania fragments which had occurred during the firing treatment was observed.

Abstract: A fuel material evaluation was made by destructively examining a full-scale experimental fuel element, irradiated in the SRE to a maximum of 850 Mwd/MTU.

The objective of the study which is being carried out under contract AT(30-1)-2477 is the exploration of all aspects of research in water resources and supply to determine the potential for using radioisotope technology in this research. Problem areas in the application of tracers in this research are being investigated through the evaluation of past experimentation with radioisotopic techniques and through discussions with those who are active in this work. A series of suggestions relating to these techniques will de drawn up to indicate which techniques should be developed further in order that more extensive applications may be found for them.

From abstract: Liquid alkali metals were circulated in a series of structural alloy loops under reactor radiation at high temperature. The first of these loops was a lithium-stainless steel (type 316) system, and the remainder were sodium-Inconel. No effect of radiation other than radioactivation was found. Mass transfer and metallurgical processes attributable to the operating temperatures were observed."

A report about mechanical properties of dilute uranium alloys are being investigated in an effort to develop a high-strength alloy for fuel elements. Elevated temperature tensile tests were made on two dilute uranium-aluminum alloys, and several ternary alloys were arc melted.

A report about equipment being constructed to measure the thermal conductivity and electrical resistivity of irradiated uranium rods clad in Zircaloy 2, with NaK as the heat-transfer medium.

Introduction: The Laboratory follows the recommendations of the National Committee on Radiation Protection concerning permissible exposure limits for those working with radiation. A system of controls and regulations has been established which should ensure that no person at the Laboratory will receive more than the permissible exposure. This manual is intended to provide the minimum background necessary for intelligent cooperation with the regulations.

From introduction: It is the purpose of this study to present field measurements of dispersion in a river and a canal, whose characteristics are unlike streams in which similar work has been done. The Colorado River and the Pierce Canal were selected for testing.

The spectrum of the mono-energetic neutron transport operator for a homogeneous sphere where the neutrons are scattered with spherical symmetry in the laboratory system is considered.

Technical report describing that void measurements were made in the 1/2-inch by 1-3/4-inch rectangular channel, for both flow up and flow down, at pressures of 600, 1000, and 1400 psia, and at various flows and quantities. Results at 1000 psia and 20 percent quality show that for the lowest flow both the void distribution and the average void are much different for flow down than for flow up, the void fraction for flow down being much higher. However, when the flow is increased both the void distribution and average void for flow down tend to approach the corresponding values for flow up. At 1000 psia, both flow up and flow down, the void fraction for 5 percent quality increases gradually from the wall to the center of the channel, and peaks at the center. At 20 percent quality, the void fraction increases abruptly from the wall and tends to be constant over the middle 65 percent of the channel. the void fraction for flow down is always greater than for flow up, other things being equal.