This is a progress report on the work of ore tressing and pyrometallurgical studies as well as a study of chemical work on phosphates. This report covers the month of November, 1947.

Report discussing theoretical reactor physics, applied reactor physics, the Alpha Experiment, nuclear measurements, and shipboard reactor studies performed during October 1949 at the Knolls Atomic Power Laboratory.

Report discussing "preparation of some stable complexes of uranium hexafluoride with sodium, potassium, and thallium fluorides...Such compounds, reported as stable in air and of low vapor pressure, offered promise as convenient sources of unoxygenated hexa-valent uranium without the difficulties associated with the use of uranium hexafluoride itself."

From abstract: "Results of tests investigating the effects of feed and scrub acidities on the extraction of uranium and contaminants from process slurries by tributyl phosphate-Gulfspray Naphtha in a Scheibel continuous extractor are described. Studies on the fractional precipitation of MgX from a dilute sulfuric acid system throw considerable light on the probable constitution of MgX. Further data on the effect of acidity on the extraction of molybdenum and vanadium into ethyl ether are presented.

The coefficients of thermal conductivity of aluminum-bismuth metal-to-metal bonds, and of aluminum and bismuth surfaces in contact under pressure, were measured.

The uptake of carbon dioxide by plant roots preparations has been demonstrated by various authors. In addition to confirming the fact of fixation, I have investigated the effect of a number of factors involved and the compounds in which the absorbed carbon appears, using carbon-14.

Observations on sheep representing flocks in Utah adjacent to the Nevada Proving Ground were compared with findings made on experimental sheep exposed to various amounts of radioiodine. The Utah sheep showed no evidence of the radiation damage observed in experimentally treated sheep. Estimations of amounts of radioiodine on vegetation required to cause serious thyroid damage following a contamination event are included.

Thermal cycling tests on uranium have shown that the dimensional changes that occur on cycling in the alpha range are directly related to both the texture of the material and its grain size: cold rolled rods generally elongate in the direction of rolling, while the same rods, after a beta-treatment, grow at rates several orders of magnitude lower. This considerable improvement by beta-treatment has been attributed to the texture randomization accompanying the heat-treatment. In the course of this heat-treatment, however, considerable grain growth occurs, which ahs the effect of causing surface roughening on cycling (also referred to as "bumping"); fine grained material generally retains a smooth surface. These observations led to the speculation that the most desirable structure in uranium, from standpoint of dimensional stability, is one that combines both a random texture and a fine grain size. Heat treatment of rolled rod offered no easy method to obtain such a product; powder metallurgical techniques, however, appeared ideally suited for the purpose. To this end, early in 1949, the Sylvania Electric Products Company initiated a program to develop suitable techniques for producing uranium powder compacts having the above-mentioned desired characteristics. Because of the availability of thermal cycling equipment at Argonne, …

The hydrogen contents of several types of fabricated uranium have been determined by a vacuum method and expressed in terms of ccH2/ccU. The data indicate that alpha-rolled metal contains about 0.25 ccH2(STP)/ccU whereas beta heat-treated uranium yielded values between 0.30 and 0.37 cc per cc. Restricted efforts were made to determine where in the heat treatment the 5 to 10 cc of hydrogen per slug were taken up. It appears that no one operation is wholly responsible for this additional gas, although reactions between beta heat treated surfaces containing microscopic defects, and nitric acid may possibly play a large role. In general it may be said that slug produced by powder metallurgical techniques contain less hydrogen than pieces produced by rolling and heat treatment.

The following report measures neutrons and gammas in solid B4C, as well as measuring H2O containing .5% boron by weight in the lid tank. Quantities measured in the following report in borated water are: thermal neutron distribution along the center line of the source (Z); fast neutron dose vs. Z; Gamma dose vs. Z; and neutron absorption by boron within solid B4C.

This is the thirty-seventh progress report of the Laboratory for Nuclear Science at the Massachusetts Institute of Technology. Progress during the period of June 1, 1955 through August 31, 1955 is reported on: (1) Chemistry of the fission elements group, (2) Nuclear chemistry (inorganic) group, (3) Nuclear chemistry (organic) group, (4) Cosmic ray group, (5) Elementary particle scattering group, (6) Neutron physics group, (7) ONR generator group, (8) Radioactivity group, (9) Cyclotron group, (10) Synchrotron group, (11) Theoretical group, (12) Personnel listing.

The majority of two-phase flow problems involving equations of state are solved by use of point-wise utilization steam table values. In this manner, problems involving the use of the various flow equations of continuity, momentum and energy are generally forced into iterative solutions. Considerable effort towards the development of an analytical expression for the state equation seems indicated so as to simplify the analysis of two-phase problems, particularly apparent in the analysis of systems undergoing phase transformation as demonstrated by the significant difference between simple theory and experimental critical flow determinations. The assumption of homogeneous, equilibrium mixture is indicated as a first attack upon the problem.

Results are summarized on theoretical considerations of the excited states of the Ca isotopes, experimental studies of the level structure of Ca42 and Ca44, studies of the production of circularly polarized bremsstrahlung by beta rays, the Moller scattering spectrometer, and the Moller scattering coincidence experiment.

The purpose of the test was to check the extraction crane rails in the area of the reactor pit for level and parallelism. The west extraction crane rail exceeded the allowed tolerance of 1/32 inch at only one location. The elevation of the north bumper was out of tolerance by 1/64 inch. The east extraction crane rail was consistently lower than the west rail by as much as 8/64 inch. The east rail was parallel with the west rail within allowable tolerances over the length tested except at one location where the transit was located, approximately 41 feet from the north bumper.

The purpose of the test was to determine the radiation levels inside the concrete enclosures but outside the reactor plant containers after shutdown following plant power operation. Radiation levels at the survey points in the 1-AC and 10BD Boiler Chambers Enclosures and in the Reactor Container Enclosure indicated that no significant radiation hazards were present approximately 25 minutes after all rods had been inserted. The radiation levels approximately 4 minutes after shutdown at the survey points in the Auxiliary Chamber Enclosure indicated that several points were above background, the highest test level being obtained in contact with the East Auxiliary Chamber container drain pipe.

Abstract: Critical experiment studies were performed, varying the parameters U235, B10 and metal to water ratio, in the SM-2 7 x 7 core configuration with 38 stationary elements and seven control rods of the SM-1 (APPR-1) type. An experimental mock-up of the SM-1 was assembled using the basic SM-2 fuel plates. Excellent agreement between the SM-1 boron loading, determined by chemical analysis, and the SM-1 mock-up boron loading, for equivalent bank positions, was noted. Several SM-2 mock-ups, cold clean and midlife, were assembled and studied with regard to reflector effects, flow divider effects, relative control rod array worths, critical rod configurations, and relative power distributions. The results of these experiments indicate as satisfactory a U235 loading of 36.4 Kg and a B10 loading of 63.4 grams for the SM-2. Attention is drawn to numerous power peaks present in the active core. The open seven control rod array has a slight reactivity advantage over the closed seven array and consequent minor disadvantage with respect to "stuck rod" criteria.

The original goal of this investigation was to compare the thermodynamic characteristics of the gases in and behind the shock fronts in gases at initial pressures in the millimeter range and to compare these characteristics in the geometries of single and double discharges. The shock fronts were not visible, so it was not possible, at these pressures, to get visual data from the shock front itself. The parameters giving the properties of the gases were faces. Measurements made with an image converter camera (which is still in the development stage) agree well with these made with a photomultiplier tube. Differences are observed between the front velocities in the cases studied. These are of the order of 3 to 15 per cent. Considering the nature of the shot to shot fluctuations in the discharges and the inductance variation between the single and double discharges represent a physical difference. The mathematical treatment which says that two equal strength colliding with a wall behaves, has not been shown to be inadequate by this investigation. It was hoped that a stronger confirmation could be fien to the theory, but the accuracy of the data does not warrant it.

"A new phenomenon which can, under certain circumstances, account for anomalous magnetic and spectral behavior of planar nickel(II) complexes has been discovered. This is a molecular association of the solute molecules in solvents of low coordinating power. It is shown that the magnetic moment and spectrum of bis(2.6-dimethyl1-3,5-heptanediono)nickel(II), Ni(DIBM)z, dissolved in toluene, are dependent upon both temperature and concentration.

The development of nuclear reactors and other nuclear particle sources has given the analyst a new analysis method which can be successfully applied to the determination of microgram and submicrogram quantities of many elements. Known as "radioactivation analysis", this method is one in which an "activation" by some type of nuclear reaction is used to produce a radioactive isotope of the element to be determined. Since this radioisotope decays with its own characteristic radiations and half-life, it is possible to make radioactivation analysis a very specific analysis. Chemical separations of the radioisotope are employed whenever necessary and its radioactivity measured by some type of radiation counter.

Abstract: The results of activity buildup studies in the SM-1 performed during Core I lifetime (June 3, 1957 to April 28, 1960) are reported. Data are presented on the extent, nature, and mechanism of the buildup of long-lived gamma emitting nuclides in the reactor primary system. Radiation levels after reactor shutdown are presented, as well as mathematical equations used to account for the observed activity levels. The data have shown that Co60 is the major contributor to radiation levels in the SM-1. Co60 activity arises from the cobalt in Haynes 25 alloy flux suppressors, and the cobalt impurity in stainless steel. After 35 months operation at an average power level of 55%, deposited Co60 activity accounted for approximately 83% of the total radiation level (mr/hr) contributed by the long-lived gamma emitting nuclides. The contribution of the primary coolant activity to the total radiation level is insignificant when compared to the contribution of the activity deposited on the walls of the system. The radiation level on the super-heater side of the steam generator was about 1400 mr/hr after 35 months of reactor operation. The percentages of Co60 activity in the coolant and in the deposits were not the same. This indicates …

The power of nuclear track research emulsion as a fast neutron dosimeter is examined in the exposure of a human phantom to PuBe neutrons. Semiautomatic track scanning and high-speed data analysis obviate the major disadvantages of this dosimeter, and allow the following basic information to be obtained without a serious cost in time: the rulative proton recoil energy spectrum, the absolute differential proton track den sity spectrum, and the average proton recoil energy at various locations in the phantom. From this are calculated the total absorbed local tissue doze due is proton recoils, the local thermal neutron intensity, and that portion of the tissue doze due to thermal [formula] tracks.