Seven runs were made with the system Penn. Ref. Co. "Supersol" (dispersed) water (continuous) to investigate the effects of pulse frequency, amplitude plate spacing, volume flow ratio, and throughput on backmixing, using the technique of continuous injection of a tracer solution into the packed section. Backmixing was found to be surprisingly insensitive to all the above variables over the range studied with the exception of pulse amplitude and continuous phase flow rate, showing greatest dependence on the later. Backmixing increased with decreasing continuous phase flow rate and increased with pulse amplitude.

The monitoring of thermal and resonance neutron flux in a thermal reactor having high flux over periods of time from 1 to 12 months using think Co foils is considered. Special attention is paid to the many correction factors to be applied to the activation data; neutron temperature, effective cadmium cutoff energy, burnout of Co59 and Co60, and decay of Co60. Results on a homogeneity test of 10 mil, 0.08% Co-A1 alloy foils is given.

The effects of oxidation and irradiation on the microsurface structure of pile graphite have been investigated by measuring the surface area and pore size distribution of several samples. The results obtained for both oxidized and irradiated graphite samples indicate that changes in surface characteristics which occur are determined by the flux, temperature of irradiation, and gaseous atmosphere in which the radiation takes place.

In connection with the study of aqueous-tributyIphosphate (TBP) systems, the study of the interactions of various diluents with the TBP has been extended. The diluents used were mineral oil, Amsco 125-90W, dodecane, n-hexane, cyclohexane, benzene, n-octyl bromide, carbon tetrachloride, chloroform and pentachloroethane. The solubility of TBP in water from solutions of these diluents and the solubility of water in the organic phase was determined. For the paraffin hydrocarbons as diluents the solubility of TBP in water was found to increase with increasing molal volume of the diluent. No evidence for the formation of TBP-water complex of simple mole ration was found.

A first iteration of the diffusion theory result is executed for the thermal flux distribution in a 7.5" graphite-uranium lattice cell using the integral equation formulation of transport theory.

The preparation of radioactive metallurgical specimens for microscopic examination is one of the responsibilities of the Radiometallurgy Sub-Unit. An abrasive cut-off machine development program, based upon a previous experimental model, was undertaken to provide a method for sectioning of irradiated materials without undue personnel exposure or spread of contamination and finally to provide data for the design of an abrasive cutting unit for use in the work cells in the Radiometallurgy Building. A horizontal-feed type set-off machine, powered by a 7 1/2 hp motor with V-belt drive, has been developed for the submerged sectioning of irradiated uranium and is currently being used successfully to obtain samples for metallurgical, chemical and physical investigations without excessive personnel exposure or spread of radioactive contaminates.

A laboratory test was performed to determine if a 10% oxalic acid solution could be safely be employed as a substitute to 2% chromic acid plus 5% phosphoric acid for removal of corrosion products from aluminum corrosion samples or slugs.

Ionization measurements of water vapor in vapor-liquid equilibrium were made with a series of chambers on a tritiated water sample which was prepared by burning T2 to T2O and diluting it with H2O. A correction was made for the difference of vapor pressures of HTO and H2O. The effect of HTO adsorbed on chamber walls and electrodes was eliminated from the final result. Using Gerbes data on the number of electron volts to produce an ion pair in air, agreement obtained between the measured source strength and the source strength as computed from pressure, temperature, volume, purity, and dilution data on the original gaseous T2 sample.

Plankton collected from the Columbia River by the net method and by the centrifuge method were compared. The centrifuged plankton (nannoplankton) exceeded the net plankton in weight, in abundance of organisms and in radioactivity. Similar seasonal trends were present in both types of plankton.

A pile gas leak detection system consisting of a purchased mass spectrographic type of helium detector, a long sampling line for use in remote or relatively inaccessable locations, a pump to pull a continuous sample of gas from the tip of the probe to the detector, and a rotameter to measure the gas flow rate in the sampling line has been developed, calibrated, operationally tested. The system is practical for use in locating all pile gas leaks larger than about 0.1 cubic foot per hour.

An analytical method for Cu-64 in reactor effluent has been studied based upon electrodeposition of the active copper with inert copper carrier. A two hour plating time was employed at a current density of 10 ma/sq cm and four volts across the cell. A stainless steel cathode plate was used. Carrier yields of greater than 80% were obtained with a standard deviation of the yield-corrected counting rate as low as 0.24%. Very little, if any contamination by other radioactive elements present was shown by decay curve studies. Self-absorption and self-scatter factors to correct the counting rate were obtained.

A continuous gamma-monitoring instrument capable of measuring the activity of the product of the Uranium Recovery plant has been developed and applied under process conditions. It has a detection limit of 15% and a normal range of up 1000% of the activity of natural uranium. Activity measurements made with this instrument have shown good correlation with laboratory determinations and are contributing to improved control of the solvent extraction process.

This report refutes earlier calculations made in the flux level of exponential piles. The results of the earlier calculations made on subcritical assemblies using critical assembly equations are in error. The calculations used in this report were more successful.

The approaches to the solution of the problem of removing or nullifying the effect of the hydrolysis of uranyl ion on acid titrations were: 1) use of a complexing agent and titration technique suitable for micro samples; 2) addition of a reagent that reacts with uranium to release 1 or 2 equivalents of acid per mole of uranium present (this permits correcting the titration value for the acid contributed by the uranium, or conversely permits an alkimetric titration of uranium); 3) separation of the uranium and acid with subsequent titration of the acid; and 4) direct titration of the sample with base. All these approaches yielded at least one method suitable for titrating acid in micro samples of uranium nitrate solutions.

This is the sixteenth quarterly report of the research and development activities of the Radiological Sciences Department, Hanford Atomic Products Operation, as before, includes some items charged to control but included for general interest. Such are identified as "not charged to research."

An experiment now in progress should give some accurate information about the thermal neutron absorption cross section of carbon 12. This report outlines and summarizes this experiment and analyzes it to determine the main sources of error and the probably error in the final result.

Abstract; Test instruments developed at the Dr. Förster Institute, Reutlingen, Germany, were considered for possible application to Savannah River nondestructive inspection problems involving stainless steel and aluminum tubing. None of the equipment can solve these problems without modifications. Several instruments are recommended for further study in connection with their use with aluminum tubing. None will be considered for use with stainless steel at this time."

From abstract: "The circumstances are described pertaining to an explosion in a TNX evaporator during the concentration of a uranyl nitrate-nitric acid solution. TBP and Amsco diluent were probably present in the evaporator charge. A laboratory program involving small-scale atmospheric and closed-vessel distillations of various mixtures of UNH, HNO3, Amsco, TBP, and water indicate that an exothermic reaction between TBP and UNH, or between TBP and HNO3, or both, was responsible for the explosion. The danger areas of temperature, TBP concentration, pressure, and heating rate are defined and recommendations are made for safe evaporator operation.

From abstract: "The Standard Pile was first brought to criticality on July 25, 1953. The first two months of operation permitted calibration of the reactor and preparation of it for use as a neutron source in exponential experiments."

From abstract: "A monitor for detection of surface-adsorbed tritium beta particles has been developed. The detecting element is a windowless Geiger tube with the counting gas flowing through it. The normal limit of detection of a single-tube probe is 800 d/m of tritium, while a three-tube probe is probably limited to about 2000 d/m. Both probes have a counting efficiency of about 10% for tritium."

From abstract: "The development, design, specification, and manufacture of special-purpose thermocouples sheathed in stainless steel for use in nuclear reactors are described. In connection with this work, a three element cable for transmitting the signal from neutron-flux measuring devices was developed."

The gas commonly used in the chamber of the Simpson Proportional Alpha Counter (ASP) is the high grade, 99% pure methane. The cost of the gas has often raised the question of finding an adequate substitute and a number of substitutions have been attempted. Commercial methane has been substituted successfully for 99% pure methane and its use is recommended in ASP counters. Neither commercial nor technical methane caused any significant changes in instrument operation.

Many factors are responsible for the rapid growth of analytical chemistry during the past ten to fifteen years. One of the most important of these factors is the greatly increased significance to present day chemistry of many elements that in the recent past were principally chemical curiosities. Since the Atomic Energy program is concerned with many such elements, it is of interest to discuss the cause for this concern and the resulting effect on the field of analytical chemistry. A number of pertinent analytical research problems at Hanford will be cited as examples.

The purpose of the short duration corrosion test was to obtain preliminary data regarding the corrosion resistance of the spring steel wire in Purex process waste solutions and to measure any changes in the tensile properties of the wire resulting from this exposure.