Summary: "Criticality was considered impossible in any contingency encountered in practice under either of the following conditions which include no safety factor: (a) In any isolated cylinder not more than 5 in. in disruptor, if the total amount of U235 present does not exceed 7.5 Eg. (b) In an isolated vessel of any shape and size, if the total amount of U235 present does not exceed 880 g. An "isolated" vessel is one which does not "see" more than 0.1 [...] other vessels containing fissionable material."

From abstract: Absolute cross sections for the production of charged secondary particles is the bombardments of aluminum, nickel, silver, and gold by 332-Mev protons, 187-deuterons, and 380-Mev alpha particles have been determined.

Absolute differential cross sections for the reaction p + p - w+ + d were obtained by detecting meson-deuteron coincidences produced by passing the 340-Mev external proton beam of the Berkeley synchro-cyclotron through a liquid hydrogen target.

We consider here the accuracy of relaxation lengths measured during the water-uranium lattice experiments. Since such an analysis for all measurements would take a great deal of time, we have applied it to just one lattice. This one (2:1 water-to-metal ratio) was chosen completely at random.

The radiolytic decomposition of tributyl phosphate has been show by burr to product gases, acids, and polymers. the acids that are formed can limit the usefulness of tributyl phosphate for the processing of radioactive materials. The study of acid formation on radiolysis therefor becomes important to us for the understanding of the mechanism of acid formation, the influence of added materials and the effect of the structure of organo- phosphorous compounds. Samples of purified esters have been irradiated in the ORNL cobalt source. Conclusions: (1) The formation of acid from tributyl phosphate during irradiation with cobalt gamma rays involves a mechanism that is not a primary step. Evidence has been obtained for a secondary reaction that is minimized by the presence of certain compounds. (2) Toluene acting as an inhibitor for radiolytic formation of acid may indicate the usefulness of an aromatic hydrocarbon diluent in processing. (3) The aromatic hydrocarbon, when phenyl, was not effective when it was part of the molecule. (4) First tests revealed that dibutyl butyl-phosphonate produced less acid the TBP and may warrant further consideration for process application.

The following report describes the results from studies based on the toxicity and metabolism of radioactive substances derived from uranium fission. Rats and mice were administered radioactive sodium and reactions and changes were studied.

A wet collection system for aerosols has been developed using fibrous media. Tests show the performance to be in accord with recently developed theory of collection by fibrous media. The effects of varying aerosol particle size, particle density, and gas velocity have indicated that inertial impaction is the primary collection mechanism. Three-year operating experience on several full scale plant installations shows reliable performance.

This report contains the results of tests which demonstrated the feasibility of using graphite labyrinth type seals, i.e., a bushing machined with alternate grooves and lands on the inside diameter to create a sufficient pressure drop to provide a satisfactory seal.

For Co60 source at 15 meters, the air-scattered gamma dose rate predicted by theory is excerpted from ORNL-1575, pp. 167-203. This is compared with experimental measurements for the same source and comparable geometry reported by Convair in CVAC-170T. After applying an appropriate correction for ground scattering as estimated in Mart-55-16T (Convair), the two results are found to be in substantial agreement.

A preliminary design study, Phase I of the ALPR project, has been made in accordance with the Army Reactors Branch specifications for a nuclear "package" power plant with a 200-260-kw electric and 400 kw heating capacity. The plant is to be installed at the Idaho Reactor Testing Station as a prototype for remote arctic installations. The "conventional" power plant as well as the exterior reactor components are described in the accompanying report and cost estimate by Pioneer Service and Engineering Company, Architect-Engineers for the project."Nuclear" components of the reactor are designed by Argonne National Laboratory as described in the present report.

Technical report covering (1) analysis of uranium bromide and chloride samples, (2) the ferric-nitrate method of analyzing uranium fluorides for fluorine, (3) spectrographic determination of boron, cadmium and manganese in magnesium metal, (4) service analyses. contributions to other problems, (5) attempted preparation of uranous oxyfluoride, and (6) corrections in previous reports.

Introduction. With the imminence of non-destructive landings of small instrumented payloads on the moon, many suggestions are being put forth as to methods of analyzing its surface. It is the purpose of this report to present a body of information which, it is hoped, will be useful in examining the feasibility of an early nuclear experiment to determine the elemental constituents of the lunar surface. The reasons for considering a nuclear approach is that it may be possible to perform an analysis without complex and elaborate manipulations, sample preparation or rigid geometrical constraints. Only those experimental designs which come within the presently-available or very-near-future general boundary conditions on weights, power, vehicles, etc., are discussed. The general approach is to consider the bombardment of the lunar surface with various nuclear beams and to examine the possible nuclear reactions which are know to be dependent on the mass and charge of the irradiated material. Then, those resultant radiations are sought which can be detected with little-or-no loss or distortion of the information which they contain.

The experimental evaluation of low (10⁻⁸ in/in/hr) creep rates are costly and time consuming. Thus, in answer to a request from the design group, the creep data on Zircaloy-2 obtained at Battelle Memorial Institute is extrapolated into the low creep rate range. Because the methods of extrapolation have not been evaluated at very low creep rates on Zircaloy, two different methods are used to analyze the creep data. The methods of extrapolation are given so that future analyses can be carried out by the design group or by other sections interested in predicting creep rates which have not been experimentally determined.

The angular distribution of the reaction p + p--w+ + d has been measured with the meson and deuteron detected in coincidence. Measurements were made at 30' and 90' in the center of mass system for an incident proton energy of 338 Mev. Similar measurements were made at 30', 60' and 90' for 332 Mev protons.

There has been a revival of interest over the last few years in the theory of the high energy photoelectric effect. this problem has been especially clarified by the work of Pratt. Others have also contributed as will be noted below. In particular these workers have shown that the formula for photoelectric absorption of hard gamma rays by the two K electrons of an atom, which is often quoted in the literature, is too large for heavy elements by a factor amounting to approximately 2 for Pb. It turns out that the error is due to a faulty procedure described in the reference (3), p. 396 for obtaining an estimate of the exact formula.

The following document describes the analysis on an attempt at separating mercury isotopes by making their environments as widely different as possible.

Laboratory studies involving fluid flow through porous media require use of fluids having low dissolved gas content. Water is the major fluid used in various and box model and soil permeability studies carried out by the Geochemical and Geophysical Research group. Tap water supplied to the 222-U Bldg. contains a large amount of dissolved air. Under the reduced pressure encountered during model studies, the air is released from solution and gradually clogs the pores of the sand or other porous material. This, of course. leads to anomalous results and cannot be tolerated in precious studies. A system was required to effectively remove the air and make available a continuous supply of desired water for the model studies.

A device has been designed which will support small spheres and cylinders in a vacuum system during a plating operation. While supporting the object to be plated, the device automatically shifts the position of the supports so that the coating is evenly distributed. This report describes the mechanism by which this motion is achieved.

From page 2: "This article first describes the Bevatron [particle accelerator] and its operation, and then discusses a portion of the research program. The principles of the machine and its early history were given in "The Bevatron," by Lloyd Smith, Scientific American, February 1951."

From abstract: This bibliography consists of references pertaining to "Effects of Nuclear Radiation Upon Electronic and Electrical Components", and to "Electronic and Electrical Components for Critical Environments". References were compiled from the Classified and Unclassified report literature and the published literature. The following indexes and abstract journals were used: Weapons Data Index, AEC Card Catalog, Engineering Index (1950-55), and Office of Technical Services, Research Reports (1956-March '57).

Much of the shielding work carried out with the Bulk Shielding Reactor (BSR) has yielded data of particular interest for the design of swimming pool type reactors, However, it is often difficult for a reactor designer to locate such data since it may be recorded in a report primarily concerned with shielding problems. Therefore, this memorandum presents a bibliography of reports from the Bulk Shielding Facility arranged according to the application of data to the various aspects of reactor design.

Progress report of the Oak Ridge National Laboratory Biology Division providing updates on various projects, experiments, and other work. This report includes a summary of scholarly output from the division and departmental activities in cytology and genetics, mammalian genetics and development, microbial protection and recovery, mammalian recovery, pathology and physiology, general physiology, biochemistry, enzymology and photosynthesis, microbiology, plant biochemistry, and biophysics.

In this study, a physical-numerical model is used to investigate processes important for cratering, or excavation, physics for high-explosive sources in desert alluvium. High explosives do not vaporize much of the geological environment surrounding the initial cavity containing the explosive. Thus, a relatively simple, and in some cases a well-known, equation of state exists for the high-explosive cavity gas for pressure greater than 1 atmosphere. However, nuclear explosives are known to vaporize a great deal of surrounding geological environment during the early part of cavity life history. This vaporized material is believed to condense late in the life history of the cavity, and prior to vent of the cavity gas to the atmosphere, such that the latent heat of condensation plays an important role in nuclear excavation. So far, no numerical-physical models of the response of a geologic environment to a nuclear explosive includes the effect of condensation on the hydrodynamics of late times. Thus, the calculation of the cavity pressure at late times including the effect of condensation is one of the current unsolved problems in the calculation of a crater formed by nuclear explosives. This study, then, develops a predictive, numerical-physical model for H.E. sources of the cavity …

In any underground nuclear explosion, the shock front that propagates from the shot point carries with it energy from the explosion, and distributes this energy by doing work on the surrounding material. In the process, the material undergoes changes in both its physical and mechanical states. If enough energy is deposited in the material, it will vaporize or melt thus changing its physical state, or cause it to crush or crack. During the past few years, special computer codes have been developed for predicting the close-in phenomena of underground nuclear explosions using the laws of physics, and the knowledge of the properties of the materials in which the detonations occur. As a consequence, a better understanding of experimental observations and measurements has evolved.