The following report presents neutron-flux measurements made with a concentric-cylinder element (Mark II) and includes axial, radial, and peripheral flux distributions.

Thus we see that the derivation of elementary age theory is based on replacing the probability of collision governed by the Milne kernel by a Gaussian probability having the same zeroth and second moments. It is apparent that the age theory distribution will fail close to the source and at many free paths from the source.

Abstract: "An absolute measurement of the 14.1-Mev (n, 2n) cross sections of Li-6 and Li-7 has been made using the large scintillator technique, resulting in cross sections in barns of 0.070 +/- 0.006 and 0.056 +/- 0.005 for Li-6 and Li-7, respectively."

The feasibility of determining particle sizes in the submicron range by employing an activation analysis - centrifugation method has been demonstrated. It is believed that this method is now applicable to the analysis of thorium oxide for submicron particles. The same techniques are, in most instance, usable in determining particle sized in other sample materials.

Facilities are to be designed for installation at Hanford for the reprocessing of irradiated, low enrichment fuels from non-production reactors, see Reference 1 and 2. The initial design of the processing facilities is to be based on processing the fuels discharged from the Dresden, Yankee, Piqua, Pathfinder and Shippingport (blanket elements only) reactors. Properties of the fuels and cladding make it impossible to completely process them in existing equipment, although the separation and decontamination can be performed in existing facilities once the fueks have been placed in solution form.

The following report provides information conducted with the purpose of ascertaining the effect of oxygen on activated charcoal at approximately one atmosphere by measuring the amount of CO2 formed over a known length of time.

An experiment was designed utilizing a charge-exchange reaction to study the decay and interactions of the neutral K mesons produced. The experiment produced no events that could be interpreted as either the decay or interaction of neutral K mesons. The nature of the experiment and the possible explanations of this unexpected result are presented in this paper.

To determine whether or not the (n,2n) reaction in Be would produce a net increase in fission neutrons in a power plant, the distribution of In resonance neutrons slowed down from fission energies in a graphite block was measured with and without a 2" of Be in front of a U3O8 slab undergoing fission. The thermal neutrons producing the fissions were obtained by slowing down neutrons from a cyclotron source. The observed distribution without Be was well represented by a Gaussian source range 36 cm. (corresponding to an initial fission energy of 3 MeV) and a similar sink of range 7.8 cm. The total In resonance intensity with Be was 5% less than without Be. On the assumption that the effect of the Be is entirely due to its different mean free path and moderating power, the In distribution with Be was calculated. Since the m.f.p. as a function of energy is not known for Be, two separate calculations were made using the highest (2.9 cm.) and the lowest (1.80 cm.) possible values for the effective Be m.f.p. Both calculated curves were found to be higher than the observed Be distribution, indicating that at least 10% of the fission neutrons …

Abstract: "A possible mechanism for the generation of magneto-hydrodynamic whirl rings near the center of the sun is described. The organic relation of the reflection of these whirl rings at the surface of the sun to the cooling of sunspots, orientation, and polarity sequence of sunspots, prominences, flares, and faculae is delineated."

Abstract: "A method has been established for the estimation of volatile organic acids in aqueous process solutions containing UNH, nitric acid, ANN, sodium dichromate and small amounts of hexone. The practice is to distill a 400 ul or 500 ul sample in the presence of an excess of phosphoric acid and ferrous sulfate under a high vacuum; a special apparatus utilizing a receiver cooled with a dry ice-isopropanol mixture is employed. The distillate is taken up in isopropanol and then titrated potentiometrically with standard potassium hydroxide solution. Since nitric acid and organic acids are present, two end points are observed. The potassium hydroxide added between these end points is equivalent to the organic acids. In the titration, CO2 from the atmosphere or in the potassium hydroxide is a source of error. The former was avoided and correction was made for the latter."

A chemical flowsheet is proposed for recovery of strontium and rare earths from Purex wastes. The iron in the waste is first complexed with tartrate and the pH is adjusted with caustic. Strontium and rare earths are extracted by a solvent comprised of di(2-ethylhexyl)phosphoric--sodium di (2-ethylhexyl) phosphate--tributyl phosphate -- Amsco 125-82. and are stripped with nitric acid. Processing the strip product through additional solvent extraction cycles yields isolated, concentrated strontium and rare earth fractions.

The following report discusses the presentation of preliminary density and viscosity data which may explain whether higher viscosities of the Deo Base-TBP systems, and a change in density differences between the two phases will lead to unsatisfactory column operation.

Tests on twenty identically prepared 26 gauge Chromel-Alumel thermocouples have been completed. It appears that wires of this material without protection are unsatisfactory mechanically and thermoelectrically for service in atmospheres of CO₂ at 1000°C.

The purpose of this work was to produce a reliable, inexpensive instrument for the detection of hard beta contamination on the clothing of personnel. Also, the monitoring was required to be accomplished without interrupting the normal activities of the employees.

A promising nonaqueous process for the recovery of uranium from spent fuel elements is under development at Oak Ridge National Laboratory. This process consists of dissolution of the fuel element in a fluoride melt by hydrofluorination at 600 to 700°C, direct fluorination with fluorine for the production and volatilization of UF6, with further decontamination of the product UF6 from fission product activity being secured in a NaF absorption-desorption step. Good decontamination is obtained in the fluorination step due to the low volatility of most of the fission product fluorides. An over-all decontamination factor greater than 106 with adequate uranium recovery has been demonstrated in laboratory scale tests using a double bed procedure for the NaF step. A pilot plant has been constructed for testing the process with various heterogeneous fuel elements. The engineering and operational features of the pilot plant are described

This bibliography contains 37 references on self-shielding cross sections. The bibliography is limited to the period from 1951 through November 1959 with the references arranged alphabetically by title. The sources used in compiling this bibliography were: Abstracts of Classified Reports Nuclear Science Abstracts

The purpose of this new series of reports is to present in roughly finished form the results of the various start-up experiments on the BNL reactor as soon as the analysis of the experimental data is completed.

Either system appears to be fairly satisfactory from a containment standpoint. Current results indicate probable over-all rates of about 0.2mils/mo for titanium vs. 1.5-3.0 mils/mo for Ni-o-nel. Tests are not 100% comparable due to changes made in flowsheet conditions, but have been of sufficient variation and length as to allow good predictions to be made. Both metals show some tendency toward local attack in Thorex solutions. These tendencies are increased by poor welding techniques.

From introduction: The present report is a summary of the experimental work on a laboratory scale to date involving the ammonia reduction and the one step TF4 processes.

The vibrational eigenvalues belonging to the ground electronic state of the HD<sup>+ and HT<sup>+ ions have been calculated. These calculations have been done for the J = 0 rotational state and neglecting the dynamic corrections to the potential. For the HD<sup>+ ion we find twenty-two bound states, and for the HT<sup>+ ion twenty three bound states.

This report focuses on the study of the stabilized pinch program made to increase the plasma temperature and improve the plasma conductivity and containment. One method proposed is the usage of a large toroidal stabilized pinch, which is described here.

Abstract: "From neutron-yield measurements made with a MnSO4 detecting solution, the average number of neutrons produced per inelastic event is determined for a series of elements from lithium to uranium for 340-Mev protons, 190-and 315-Mev deuterons, 490-Mev He3 ions, and 90- and 160-Mev neutrons. The results are analyzed in an attempt to understand the total yield measurements for thick targets and to explain the variation of yield with the atomic number of the target."

Reactivity measurements conducted in the Hanford Test Pile are interpreted to yield resonance integrals for uranium, uranium oxide, thorium and thorium oxide. The experiments were made using cadmium filters and are discussed in terms of the multiplication factor of the Hanford Test Pile.

This report follows ciritical-assembly studies on: the effect on reactivity caused by changes in axial reflector materials; the effect on reactivity and the power perturbation caused by fast safety control-blade guides; the effect of changes in fuel-element material composition; the effect of changes in fuel-elements spacing designed to produce uniform radial power-generation rates.