The following report summarizes the data taken from a series of measurements on the combustion and ignition properties of hexone. The experiments were taken at the Bureau of Mines Central Experiment Station by their personnel, and the samples were given to them by KAPL and Hanford.

This report describes the preparation and testing of corrosion on brazed, vacuum-tight aluminum joints for finned aluminum tubing to contain uranium slugs.

Abstract: "The half-life of polonium has been measured by a calorimetric method using samples several thousand times larger than have been previously available. The value is found to be 138.3 +/- 0.1% days."

The first part of this quarterly progress report details reactor theory and design, discussing the aircraft reactor experiment, experimental reactor engineering, reactor physics, and critical experiments. The second part of this report is not included. The third part of this quarterly progress report details materials research, discussing corrosion research, physical properties and heat-transfer research, metallurgy and ceramics, chemistry of high-temperature liquids, and radiation damage. The fourth part of this quarterly progress report details alternate systems, discussing a supercritical water reactor, circulating-moderator-coolant reactors. The fifth part of this quarterly progress report includes appendixes.

Abstract: The removal of both SM-1 Core I high burnup elements from the SM-1 Core II and the insertion of two SM-1 Core I spare elements i their places are discussed. Nuclear and thermal characteristics of Core II with the change are presented and conclusion related to the change in hazard potential are made. If the core change indicated by this report is made, local peaking factors will be decreased and burnout ratios will be increased. This, of course, in itself leads to a more conservative estimate of core safety. There is no conceivable reason why this perturbation may not be safely made in the SM-1 Core II.

For some time, the need has been recognized for an X-ray diffraction unit applicable to studies concerning the crystallographic characteristics of pile irradiated materials. Except for studies involving specimens of low activity, it has been impossible in the past to investigate materials which emit intense beta and gamma radiations. The exact type and degree of irradiation damage to high activity materials has been largely a matter of theoretical conjecture. The object of this report is to describe an X-ray diffraction spectrometer that can be used to collect crystallographic data from irradiated materials.

Report discussing progress made by the National Research Corporation in developing preparation of ductile zirconium for the month of August, 1949.

Abstract: This technical report consists of series of drawings of the instrument with the following explanation. The modification of the Simpson Methane flow proportional counter consists of a means for inserting and replacing samples into the chamber through an air-lock device which avoids the introduction of even a small quantity of air into the active volume of the chamber. This is accompanied by sweeping out the small volume of the air-lock containing the sample with methane gas before the sample is introduced into the chamber -- this sweeping out requiring only a few seconds. The mechanical construction is somewhat simplified over that employed in the Simpson counter design, although the electrical and counting characteristics are essentially duplicates of those employed in the Simpson version. Voltage plateaus about 400 volts long, flat within 1% per 100 volts are obtained with the counter, with the operating point at about 2500 volts for methane at one atmosphere pressure. A plateau extending over a range of about 40% variation in amplification factor is obtained. Standard samples have been checked to standard deviation of +/-0.3% over a period of one year. The counter is rather gas-tight and is ready for use within about ten minutes …

Uranium ore from Radium Hill, South Australia was leached with hot sulfuric acid solutions and the uranium recovered from solution by uranous phosphate precipitation or by use of anion exchange resins.

Report discussing experiments on the interaction of neutron-absorber materials and metal matrix materials used in the fabrication of control rods, such as "boron, cadmium, and some of the rare-earth elements such as gadolinium and europium...In order to evaluate the reactions that might occur during fabrication and use, experiments were carried out in which combinations of the various control materials were heated in intimate contact with the several matrices at elevated temperatures."

A commercially available electronic high vacuum pump has bee tested on various types of mass spectrometers used at the Oak Ridge Gaseous Diffusion Plant. Considerable savings in operating and maintenance costs can be realized from the use of this pump. the greatest savings result from the elimination of the cold trap required for the diffusion pump whether it is cooled by liquid nitrogen or by mechanical refrigeration. additional savings results from the fact that the pump currently is usually an adequate indication of the pressure in the spectrometer tube and that a continuously running mechanical fore pump is not required.

Quarterly report discussing the progress made with various projects at Argonne National Laboratory during the period from January to March 1948.

"We want to point out that there is a possible method for determining the anomalous magnetic moment of the Λ from the observation of metastable states of hyperframents. There are two possible sources for the apparent difference of binding energies of a hyperfragment. One of these comes from the difference of Q values due to the decay into an excited and ground states of the residual nucleus. The other possibility will arise if there exists a metastable state of the decaying hyperfragment."

From abstract: "The mass spectra of the α-amino acids have been obtained in a mass spectrometer equipped with a heated crucible ion source. Correlations of these data have been made with the molecular formulae of the ion fragments, and mechanisms leading to these fragments are proposed. Comparisons of these data have been made with the mass spectra of the ethyl esters of the amino acids and with other carboxylic acids and their esters."

The following report describes the electron spectrum of protactinium derived from 23 minute thorium 233 that was produced by neutron capture in stable thorium.

From Introduction: "The self-shielding characteristics of a number of absorbers and of U-235 and U-238 have been investigated in PPA-20 (66°). Most of the measurements have been made in Ring 3 at the core mid-plane. The foil doubling technique was employed. Particular attention was given to 'thin' foil regions for the purpose of extrapolating the data to zero thickness."

The purpose of the test was to determine the direction and magnitude of any drift in the temperature sensing elements and the receiver-indicating units for the primary loop and pressurizer resistance thermometers. To obtain intercalibration data for various temperature sensing elements in the primary coolant system. To obtain data on the difference between the calculated signal generated by the BF-3 counters, considering the known rate of decay of the PO-BE source, and the measured values. Determination of temperature sensing element and instrumentation drifts could not be made due to a lack of comparative data. Five temperature intercalibrations were performed using the calibrating Tc resistance thermometers as a standard. The data obtained from the nuclear instrumentation was too erratic to form any conclusions.

The purpose of the test was to determine the direction and magnitude of any drift in the temperature sensing elements and the receiver-indicating units for the primary loop and pressurizer resistance thermometers. To obtain intercalibration data for various temperature sensing elements in the primary coolant system. To obtain data on the difference between the calculated signal generated by the BF-3 counters, considering the known rate of decay of the PO-BE source, and the measured values. Of the 62 core thermocouples observed 19 were either reading less than 400 F or were reading in excess of 20 F from the calibrating thermometer temperatures. In each case the thermocouple was considered defective. The remainder were within 2 per cent of the calibrating thermometers. The primary loop (Norwood Indicators) resistance thermometers all read with 0.2 percent of the calibrating thermometers. No conclusion could be made for the pressurizer temperature instruments or the boiler Tb resistance thermometers, except that the 1A boiler temperature varied 10 F to 20 F from the 1Band 1C boiler temperatures. A laboratory calibration of this instrument will be made. The data obtained from the source range nuclear instrumentation was too erratic to form any conclusion. No drift evaluation on …

"Using the Brookhaven fast chopper, transmission curves were obtained for the 6.70 +/- .06 ev resonance in U238 using four different thicknesses of natural uranium metal." The measurements for the transmission curves are summarized in the table provided.

This technical report presents necessary information required to operate the raw materials feed preparation plant. The information herein is intended to serve as a guide to operating personnel and to provide general data concerning the process.

"A program of creep-rupture tests of several bars of Beryllium has been completed. The tests were made at 1200, 1400, 1550, and 1700 F. in protective atmospheres of tank helium or hydrogen. The results are given in a summary table and by creep and design curves. A description of the test set-up is included."

The purpose of the test was to determine critical bank heights and bank worths for various rod configurations at ambient temperatures. The critical rod bank position and bank worths for four different control rod bank rod configuration were determined after 5032 EFPH's of operation. The value were corrected to a reactor coolant temperature of 145 F and a pressure of 400 psig. The bank worths were corrected to 145 F so that the results of the performance could be compared with the results of previous performances.

From introduction: "The study's objectives were to determine the approximate rate of general corrosion so as to reveal; any abnormal corrosion occurring during processing operations; to determine the suitability of a large variety of alloys and plastics as materials of construction; and to ascertain process conditions which would minimize corrosion."

A comparison of the simple impact theories of line broadening by electrons with the detailed computations of Kivel, Bloom, and Margenau.