Report documenting the progress of the Army Gas-Cooled Reactor Systems Program to develop a mobile nuclear power plant for military field operation.

The first step in a proposed processing method for recovery of uranium from graphite-uranium fuels consists of oxidation of the fuel by oxygen to volatilize the carbon. Residue ash from the combustion step can be treated in a variety of ways to recover and purify the uranium. The combustion step may be caried out by contacting the solid fuel in a fixed or moving bed with a stream of oxygen-bearing gas in a tubular or annular reactor. Oxidizing gas may be introduced to the reactor at several points up the reactor and there may be continuous or intermittent addition of fresh fuel and removal of residue ash.

The first man-made nuclear reactor -- or "pile" as it was then called -- was rather hurriedly improvised and operated in a crowded space under the athletic bleachers of Stagg Field at the University of Chicago on December 2, 1942. Just prior to this time, there began the assembly of a group of physicists with an unusual assignment. They were determined that radiation hazards of unprecedented proportions must be coped with successfully in the conduct of reactor programs as planned. Since these physicists were to be concerned with the health of radiation workers, they were called health physicists. There was no formal instruction available to this first group of health physicists and they perforce received training as they felt their way by firsthand experience and by trial and error. Health physics at Oak Ridge National Laboratory from the very beginning has been organized into three principal areas: applied activities, education and training and research.

Boron-10 has a high thermal neutron capture cross section (3880 barns). Following neutron capture, the subsequent nuclear disintegration produces an alpha particle and a lithium-7 nucleus with the release of an average of 2.34 MeV for the particle irradiation, and in 93% of the reactions there is also the emission of an 0.48 MeV gamma ray: [equation not transcribed]. The kinetic energy is divided between the lithium-7 nucleus and the alpha particle giving the equal and opposite momentums with a range in tissue of about 8-14μ or approximately 1 cell diameter (1). This fact and the reported favorable partition of boron between tumor and the normal brain suggested a possible therapeutic usefulness which has been investigated clinically. The object of our study is to document the biological effects of the B10 (n,α) Li7 reaction on the brain of dogs injected with boron-10 30 minutes prior to irradiation with thermal neutrons. For this, we felt it desirable to estimate a dose for the boron-10 reaction which if exceeded, produces destruction of normal tissue. This dose could then be a reference dose to be utilized as a maximal limit for the irradiation of normal tissue. We have assured that the largest fluence …

The biological evaluation of the thermal neutron capture reaction of boron-10, B10 (n,α)Li7 + 2.786 MeV, has previously been studied, using different particles from the boron-10 thermal neutron capture reaction compared with 250 kvp x-rays has been reported as 1.05 for spleen-thymic weight reduction (1), as 1.5 to 2.0 for skin lesions in pigs (2), and 1.87 for skin lesions of the rabbit's ear (3). The significance of such a calculation is felt to be unreliable for the boron-10 reaction in animals because of the vagaries of dose determination resulting from irregular boron distribution, and by the presence of an adventitious irradiation from fast neutrons and capture gammas that is inadequately determined at present. Our present experiment attempts to circumvent the difficulties attendent to studies of the boron-10 reaction in animals by comparing the effect of this reaction on the proliferative capacity of HeLa cells with those produced with 250 kvp x-ray.

Abstract: This report gives a general description of the single stage axial compressor blade test facility located at the Oak Ridge Gaseous Diffusion Plant, Oak Ridge, Tennessee.

In these lectures we will discuss some examples of information about magnetic properties of solids which can be obtained by neutron scattering. We consider a scattering process in which a neutron with wave vector k and spin σ is incident upon a solid in state q>. (Here q stands for all of the quantum numbers which describe the state of the solid, such as spin and orbital electronic states, phonon numbers, etc.) After interacting with the solid, the neutron goes off with wave-vector k' and spin σ', leaving the solid in state q'>. In performing an experiment of this sort one does not usually observe the initial and final spin states of the neutron or the initial and final states of the solid. We must then sum over all possible final states and average over all initial states.

The present core of the Brookhaven Graphite Reactor consists of some 4900 highly enriched uranium fuel loaded in 615 horizontal fuel channels passing through a 25 foot cube of graphite moderator and reflector. The core is divided into two halves (north and south) by an 8 cm. wide vertical gap in the center of the graphite. The cooling air enters the reactor through inlet filters, at the rate of 270,000 CFM, passes into the central gap and flows bi-directionally through the north and south halves of the core. It then enters the collecting plenums and flows into the north and south ducts. The air is first monitored by the north and south exit air monitors located within the pile building. These are moving filter tape monitors with beta scintillation detectors. They are essentially operational monitors and are maintained by reactor operations. They are essentially operational monitors and are maintained by a reactor operations. The air then passes through the exit air filters, heat exchanger, venturi and on to the fan house where the north and south ducts join. After the fan house the air is monitored by Argon-41 by a Kanne ion chamber syste.

Investigations on the relative biological effectiveness (RBE) of densely ionizing radiations (with high LET, rate of linear energy transfer) are of importance in both fundamental and applied radiobiology. In the latter, they serve as a basis in setting permissible exposure levels for types of radiation about which little long range experience is available. Some of the best RBE studies have been done on chromosomal aberrations. The difficulty is determining RBE on the basis of chromosomal exchanges or 2-break aberrations is that the dose-response curves differ for radiations of different LET and dose rate. The dose-squared term tends to predominate with radiations of low LET (such as γ rays and most X rays) and high doses or dose rates; the linear term dominates with high LET tracks in general and at low doses or dose rates. The shape of the curves is thought to reflect the existence of two classes of mechanisms by which chromosome exchanges are produced; exchanges caused by the passage of a single ionizing particle account for the linear component of the dose-response curve, exchanges due to the interaction of effects of two independent ionizing particles are responsible for the dose-squared component. This model has been amply confirmed …

If one injects into an animal H3-thymidine, 50% of it is incorporated into deoxyribonucleic acid (DNA), within approximately 30 to 45 minutes, while the rest is catabolized. A storage of H3-thymidine for later incorporation into DNA does not occur, on the basis of available evidence. Once incorporated, the label remains bound to DNA until cell death and no unequivocal evidence has as yet been presented to indicate metabolic renewal or intracellular turnover of the DNA molecule. The loss of labeled DNA from the bone marrow is therefore directly influenced by the rate of proliferation of the various cell types with release of mature cells into the peripheral blood.

In brief, these facilities consist of a 250 KvP X-ray generator; two areas of a research reactor, one a well thermalized unit of moderate capacity and a larger area with a mixed thermal and fast neutron distribution, all of which are used for brief, acute exposure. A 10 acre field, currently with almost 4000 curies of cobalt 60, serves to irradiate entire plants for either short or long periods of time. Recently, the flux density of the thermal column was increased by a factor of 5 over the original density. This was accomplished by lowering the thermal column 12 inches deeper into the reactor shield. Fast neutrons at this higher flux density are also available to the cooperator. An additional facility available to the program is the array of kilocurie gamma sources in the Nuclear Engineering Department of Brookhaven National Laboratory.

Abstract. The kangaroo rat is readily tamed and has certain characteristics that make it unique and of interest in highly specialized research programs. Studies were conducted on its ability to exist on a dried diet with only a bare minimum of water and that obtained from succulent plants. Hematological studies indicate that the kangaroo rat exhibits a different hematological distribution of cells than the mouse or rat. The lymphocyte constitutes 81.4% of the total leuokocytes. The hematocrit has a value of 46 to 48 in spite of the high degree of water conservation practiced by the animal. The response to ionizing radiation of this species does not differ from that reported for the mouse or rat. Behavior studies indicate that the digging characteristics of the kangaroo rat are similar to those of the gerbil. Furthermore, the animal shows definite psychotic tendencies under the influence of psychotomimetics like LSD-25 and psilocybin. An evaluation of the physiological responses of isolated tissues from this animal as well as its responses to anesthetics is being undertaken to evaluate its further usefulness in the laboratory.

Activities in a program to develop techniques in the use of pulsed neutron sources to measure shutdown parameters related to large thermal power reactors are reported. The experimental work centers around aspects of detecting neutrons in the presence of 10/sup 7/ r/hr gamma fields. Boric acid experiments and Humboldt Bay experiments are reported.

"Design work was completed and construction initiated on a prototype field altimeter based on the gas density dependence of Townsend discharge current in an electrical discharge. The design of an ion tracer air velocity meter for laboratory applications, and construction of three units were successfully completed. Theoretical and experimental support is presented, showing the applicability of the ion tracer system to the accurate measurement of linear gas velocity. The operating range of the laboratory meter is 150 to 2500 ft/min at ambient pressures between 200 mu and 30.0 mm Hg. Further investigations on the application of the ion tracer concept to flowrate measurements are presented. By generating velocity profile curves with an ion tracer calibrated thermoanemometer, it was possible to determine the flowrate for 2 flow and pressure conditions; 37.5 cfm at 19.6 mm and 75 cfm at 9.8 mm Hg. Comparison with a calibrated Rotameter technique was within 5% in both cases. Also presented are some preliminary investigations leading to the development of a generalized ion tracer flowmeter for low gas densities. Results of some supplemental electrical discharge experiments in rarefied atmospheres are described. It was observed that electrical oscillations could be produced in a low density gas discharge, …

Technical report. From Abstract : "The crystal structure of bis(meta-chlorobenzoyl) methane has been determined by three dimensional anisotropic least squares refinement of scintillation counter data. The molecule was found to be nearly planar with a maximum deviation from the least squares molecular plane of 0.068Å and an average deviation of 0.023Å. Fourier transform techniques to locate phenyl rings provided the key to the structure determination. The intramolecular bond distances and thermal parameters of the oxygen atoms support a resonant, enol ring with a symmetric, intramolecular hydrogen bond. The structure confirms conslusions from the structure of bis(meta-bromobenzoyl) methane where the symmetry of the molecule was forced by the crystal symmetry."

A series of W-5 Re/W-26 Re thermocouples have been electron beam welded at the Hamilton Standard Division at our request. This technical report is a summary of our evaluation of these joints. These weldments did exhibit incomplete fusion in cap welds and some porosity in undesirable lead junction shapes. In fairness, this was a single attempt to make a difficult joint, and the objective of ungrounded 1/16 OD clad joints was met. As noted by Hamilton, two changes are necessary to improve this joint design: (1) swaging to forming the clad end rather than crimping prior to cap welding. (2) using a fixture with rotary motion on a tilting axis.

Technical report. From report : "The method of least squares refinement is based on the prediction of the theory of errors that, if the errors of the observed structure factors follow the Gaussian distribution, the most nearly correct atomic parameters will be those which result in the minimization of the residual R = Σi [√wi(|Fo| - |Fc|)i]2."

Technical report. From Abstract : "Accurate measurements on boiling points and surface tensions of mixtures of benzyl acetate with dioxan, aniline and meta-cresol over the entire range of concentration are reported. The results have been analysed in terms of quasi-crystalline model which is partially successful in representing the composition dependence of heats of mixing, boiling points and surface tension except for composition dependence of boiling points of benzyl acetate and meta-cresol."

From Introduction: "One part of this study, which is presented in this Monograph, consists of an analysis of electric energy usage and electric power demand data obtained from a sample group of occupied houses at Little Rock Air Force Base in Arkansas, equipped with heat pumps, water heaters, cooking ranges, clothes dryers, and miscellaneous appliances all operated by electricity."

The following report is part of a series of quarterly reports discussing investigations on the development of zirconium-base alloys having corrosion resistance and strength superior to Zircaloy-2 and/or development of materials of equivalent corrosion resistance by exhibiting enhanced strength. This report covers the period between May 29 and June 18 of 1958, made by the United States and the European Atomic Energy Community (EURATOM).

Abstract: This technical report covers development of an AG-Cd-In alternate absorber section for Army Type SM reactors. It describes the absorber material composition and the geometric configuration. It gives the nuclear and thermal analyses supporting this configuration and a detailed description of the manufacturing practice employed in fabricating the final design component.

From abstract: "The formation constants of the RChOH- species, formed by interaction of individual rare-earth nitrilotriacetate species and KOH at 25°C and an ionic strength of 0.1, have been determined by the potentiometric method, i.e., computed from the pH values of equilibrium mixtures containing varying proportions of rare-earth complex and base. The relationship of these constants to the ion-exchange separation of rare earths at high pH has been discussed."

Technical report describing and evaluating the the three experimental methods for obtaining equation of state data at low temperatures; (1) approximate measurement of the PVT relationship by a piston-displacement technique, (2) the measurement of a heat capacity at constant volume as a function of molar volume and temperature, and (3) direct measurement of the pressure variation of the elastic constants using ultrasonic techniques. X-ray methods also might be applicable.

The General Electric Company is proceeding with an irradiation program to proof test a representative array of Savannah I fuel rods. Irradiation of a test assembly containing Savannah I fuel rods has begun and it is proposed that the results of this irradiation will permit an advance evaluation of the fuel performance and fuel burnup in the Savannah I reactor. This report covers the first two quarters of the reporting period. All aspects of the subject program have been consolidated and applicable portions are discussed in some detail.