Abstract: "The information contained in this report consists of personnel exposures to radioactive dust resulting from a thorium rolling operation."

From introduction: "This report summarizes the experimental data obtained at the San Pablo Laboratory on the corrosion of 5% Cr - 0.5% Mo steel by bismuth under conditions that allow mass transfer to occur. The bismuth is circulated through a temperature gradient by means of a thermosiphon loop."

It was shown that without further major development the detectors proposed for the Body Monitor can be expected to detect 0.02 microcurie of plutonium at the center of the chest cavity. This is the permissible body burden of insoluble forms of plutonium. The detection level can be decreased by decreasing the background counting rate. Decreases in the background can reasonably be expected; it should be possible to detect a small fraction of the permissible body burden. If it can be shown, as suggested by other work, that americium will remain with plutonium, then within at least a few months after entry into the body it should be possible to measure the plutonium by detection of rays from Am²⁴¹.

Conclusions from the study: "Radioactive dusts are carcinogenic, and can cause cancer of the lung. complete dose response curves have not yet been determined. All the parameters that render this demonstrably toxic material (radioactive dust) have not yet been evaluated. It is strongly suggested by the experimental data that duration of radiological insult to the lung is an important factor in eliciting lung cancer. The atmospheric tolerance concentrations now in use seem to afford little margin of safety."

This report describes corrosion rate of uranium in hydrogen-saturated water appears to be constant with respect to time after a brief induction period and to involve only one type of over-all reaction, in which pitting effects are slight or nonexistent.

An ex-reactor test stimulating the charging of a tubular fuel element in a Zircaloy-2 process tube showed a problem of severe process tube scratching and galling may occur if metal sliding contact fuel element supports are used. Both the fuel supports and the process tubes were autoclaved. Although the conditions of this test were severe in that the sharp edges rather than a flat surface of the supports were in contact with the process tube, it pointed out the potential problem of galling by point on small area contact supports on heavy fuel elements. This difficulty had not been observed with the lighter tubular or cluster fuel elements used in KER irradiation. In addition to the loss of metal and thinning of the process tube after a number of charge-discharge operations, these scratches may lead to localized corrosion or act as points of stress concentration.

This report deals with the (1.1) physical properties of graphite, (1.2) effects of pile irradiation on the properties of graphite, (1.3) effect of irradiation on "ceramic" materials, (1.4) exposure and dosage for radiation damage experiments, (1.5) apparatus for the measurement of the thermal conductivity of solids, (1.6) effects of radiation on ice -- the thermoluminescence of ice, (1.7) investigation of color centers and other optical properties of single crystals. (2.1) radiation chemistry of liquids, (3.1) radiochemical investigation of the spontaneous fission of Cm242, (3.2) radiochemical service, (3.3) on the one-body model of alpha, (4.1) spectrographic analysis, (4.2) chemical analysis, (5.1) the 60-inch cyclotron.

Progress report of the Oak Ridge National Laboratory Metallurgy Division providing updates on various projects, experiments, and other work. This report includes a summary of nondestructive testing, physical chemistry of corrosion, fundamental physico-metallurgical research, HRP metallurgy, process metallurgy, metallurgical materials and processing, metallography, and ceramics research.

Experimental studies on continuous denitration performed in 321 Building resulted in the development of an agitated-through-type calciner. The performance of a paddle-agitated 4-in.-diameter by 44-in.-long reactor was sufficiently promising to warrant construction of a 16-in.-diameter by 8 ft.-long semi-plant scale model. This progress report summarizes the results of studies to date employing the semi-plant scale calciner.

Production Test 313-105-13-M authorized the irradiation of a uranium - 0.4 atomic per cent chromium alloy to determine the relative stability of this material during irradiation. Five tubes, each containing six four-inch alloy slugs, were irradiated to exposures ranging from 156 to 834 MWD/T. This report describes the results of the visual examination of the bare uranium alloy slugs and the results of the test to determine slug breaking strength. The breaking strength of both the U-Cr alloy slugs and the normal uranium control slugs was reduced by exposure in the pile. The breaking strength of those U-Cr alloy pieces not cracked or broken in the jackets before examination was consistently greater than the breaking strength of the normal uranium at all exposures.

Part I. Experimental Reactors: The effect of prompt-neutron lifetime upon reactor safety was investigated for the HRT. It was found that for a given pressure rise the allowable rate of reactivity addition was relatively insensitive to the average prompt-neutron lifetime, although the rate de creased somewhat with decreasing lifetime for the higher pressure rises. With only source neutrons present and the reactor initially subcritical, the allowable rate was practically independent of the initial value of k£. For a core-pressure rise of 400 psi, the corresponding rate of reactivity addition was about 0.8% per second; for a pressure rise of 4000 psi, the rate was 2.5 to 3.0% per second. Part II. Thorium Breeder Reactor: An economic study of one-region thorium breeder reactors was completed. Where possible, the process characteristics and cost factors were the same as those used previously in studies of two-region-type reactors. The mini mum-cost reactor is about 12 ft in diameter, operating with 260 g of thorium per liter on a chemical processing cycle of about 450 days. The ratio of U232 to U233 produced is approximately 2 x 10~4 VIM in the minimum-cost one-region system, compared with 4 x 10 5 in the two-region system. The …

The purpose of this report is to provide data pertaining to the corrosion damage incurred in the use of oxalic acid as a cleaning agent for process equipment.

Radioactive decay data are used to calculate the atomic masses of the heavy isotopes, A> 203. The four radioactive families are then connected by means of neutron binding energies known from reactions on various isotopes. Finally all the masses are collectively adjusted for the best fit with mass spectrographic information available in this region. The masses so calculated are presented. Differences between masses of isotopes are estimated to have an of (plus/minus) 0.00020 mas units or about 200 Kev; the position of the masses taken collectively is in doubt by about 1.5 Mev.

The thermal decomposition of the higher oxides of praseodymium and americium have been investigated.

A two-group approximation of the fission ratios and Pu production in an infinite hollow matrix is developed

This report describes the work carried out in 321 Building semiworks equipment, to define the factors contributing to high corrosion-product contamination and presents recommendations for reducing the impurity level to meet current specifications (maximum of 200 parts total metals per million parts U).

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.

This report describes observations of a sample of Carbon-14, or radiocarbon, made using the method of mass spectrometry.

The designer's concept of a test program for the 30-Mw prototype intermediate heat exchanger and steam generator designed and fabricated as part of the Sodium Components Development Program is presented. The performance data will serve to verify the thermal design, or allow application of improved techniques to future designs, give an improved basis for stress analysis in design of future units, and demonstrate the capability and limitations of the units in relation to the performance specifications for which they were designed. Welding techniques for type 316 stainless steel are described. The specifications and operating conditions of the units are given along with instrumentation drawings showing test equipment design and arrangement.

From abstract: "The results of recent measurements on the equations of state of sodium and xenon are discussed. The experimental data for each of these are analyzed to show that the isothermal compressibility is solely a function of volume within experimental accuracy. The basic differences between the low temperature PV relationships for sodium and xenon are shown to be easily understandable in terms of the elementary theories of these substances. The range of experimental pressures (to 20 kbars) and temperatures (20°K to the triple point) is sufficiently great so as to produce significant changes in the lattice thermal properties in each case. These changes are indicated through the use of zero pressure heat capacity data in combination with the equation of state data to calculate the volume and temperature dependence of the Debye Θ. The result is quite spectacular for xenon, where a pressure of 20 kbars roughly doubles ΘD."

The nature and types of internal molecular and thermal motions that polymer chains and polymer segments undergo have a great bearing on the physical behavior of polymeric solids. A relatively new tool is now available that permits us to observe and study internal thermally-induced motions directly at the atomic or molecular level rather than from macroscopic observations. this tool is nuclear magnetic resonance spectroscopy. This talk discusses (1) the nature of nuclear magnetic resonance, (2) NMR line shapes and the influence of temperature, (3) NMR line widths and second moments as a function of temperature, and (4) lists six general conclusions.

This report discusses the field of nucleonics in the wake of the development of the atomic bomb, ruminating on the training and curriculum necessary for the next generation of chemical and nuclear engineers.

From abstract: "A pile will run steadily at an arbitrary level if it is just critical. For a pile not at equilibrium, equations of motion can be set up that contain as variables the pile power, the number of delayed neutron emitters and, in case it is of importance, also the pile temperature. The coefficients will depend on the average lifetime of the neutrons in the pile, the fractions and periods of delayed neutrons, temperature coefficients of resistivity and similar quantities. For a definite 'excess resistivity', which may be positive or negative, the power level will change exponentially with time with periods determined by the so-called 'labour' relation. For control and safety problems the transient behavior of the pile under reactivity changes has to be investigated. A number of limiting cases can be solved explicitly. A general method for the solution of the pile equations is available for small deviations from a steady state. In this case a pile impedance can be defined in close analogy to electric circuit theory."

Unanticipated radioactive contamination of the 200 Areas environs was discovered in the latter part of 1947, about 2.5 years after the startup of the Bismuth Phosphate Separation Plants. It was subsequently established that this contamination was due to radioactive particles emanating from the Separation Plants' stacks, and the need for exhaust ventilation air filtration equipment was recognized. Sand filters were installed in the fall of 1948 in the ventilation systems of the B and T Bismuth Phosphate Plants. These filter units essentially eliminated this contamination problem and have performed satisfactorily to the present time.