Report issued by the Argonne National Laboratory discussing high-flux research reactor design studies. As stated in the summary, "this report presents a reactor design to meet the needs of the basic research program at Argonne National Laboratory. The program requires some irradiation in thermal flux...and some beam experiments..." (p. 5). This report includes tables, and illustrations.

Technical report describing the investigation undertaken to determine the necessary requirements for obtaining sound bonded joints on tantalum. Corrosion and Mass Transfer Loops LTTN 237A and 427 called for fabrication of 430 stainless steel clad tantalum tubing. Since there was little or no experience at welding this material at CANEL, specimens were welded using vacuum chambers and plastic chambers as normally used for loop fabrication. Resistance welding was performed without the use of a special atmosphere producing sound bonds.

Calculations are given for eighteen stainless steel clad helium bonded specimens of UO2-ThO2 containing normal U to be placed in 6 holes in a holder in a position of the ORR not to exceed a peak unperturbed flux of 4 x 10^14 n.cm^2/sec and irradiated to a peak nvt of 1.96 x 10^21 neutrons/cm^2

Report discussing the use of chemical concentrations of certain elements in uranium deposits of the Colorado Plateau as a guide for the size of the deposits.

A report regarding chemical composition as a guide to the size of uranium deposits in the Salt Wash member of the Morrison formation, Colorado Plateau

Several experiments have been performed at ORNL with light water solutions of uranyl nitrate (highly enriched in either U^233 or U^235) in an essentially bare sphere 27 inches in diameter. This report presents the results of several calculations with elementary bare reactor theory and a discussion of the observed discrepancies between the calculated and experimental results. If the observed critical concentration is used in the calculations, the calculated effective multiplication constant is less than unity' thus a higher critical concentration would be predicted than is actually observed.

The "absolute" containment of ions in the DCX magnetic mirror field resulting from the cylindrical symmetry of the field is discussed. The regions of confinement in space and momentum are plotted for 300 Kev deuterons.

A new package type facility for corrosion decontamination studies has been designed and fabricated. This report gives a description, drawings, and comments on its operation. It has been in operation since December, 1958.

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.

In a discussion about design of cyclotron resonators, the suggestion has been made that a wide range variable-frequency system might be constructed with two coupled resonant circuits. It also would present the possibility of tuning without the switching of high-current contacts, a troublesome item now commonly used for cyclotrons. One of the circuits would be the dee and its stem which might, or might not, be tuned. The second circuit could be located out of the magnet gap in a region where more space is usually available. Tuning could be accomplished by variation of the coupling between the two circuits and/or by, say, variable capacitance of the tuned, or tunable, circuit.

A means for decontaminating the primary system of recirculating type reactor is necessary to insure operation and maintenance. This recirculation system can be contaminated by fuel element rupture products and induced corrosion product activities.

The transfer or circulation of raw dissolver solutions containing gross particulate matter presents many problems not easily overcome by standard pumping equipment. In April of 1956 the HAPO concept of a modified Archimedes screw pump was developed. Two basic models, externally powered and driven through extended shafts, were constructed and tested. Operation of these preliminary models was so satisfactory that a third unit, integrally formed into drive motor, was built and placed in extended life test. This report describes construction and testing of the third and final model.

To summarize one finds that for diffusion in a temperature gradient by a vacancy mechanism one must have E(M) < E(F). No such restrictions occur for interstitial diffusion. The spatial vacancy distribution is very nearly the equilibrium distribution if dislocations are present. If no dislocations are present then one could obtain E(M) by measurement of the spatial distribution.

Report discussing a study of the distribution, volume, and lithologies of sedimentary rocks of the Colorado Plateau, and of the distribution of elements contained within these rocks.

Plutonium Fuels Development Basic studies. Experiments to determine the effect of plutonium dioxide additions on the sinterability of UO2 have continued. PuO2 has been added to ball milled PWR grade UO2 as a physical mixture, and in the form of the mixed crystal oxide.

The use of mercury as a solvent in the recovery of uranium from spent fuels is of the interest at Oak Ridge National Laboratory. The vapor pressure of mercury is lowered by increased concentration of uranium. By dew-point measurements, the vapor pressure at 175°C was found to very between 2 and 8mm of mercury, and at 375°C, between 300 and 1100 mm of mercury, depending upon composition as described below. Plots of the log of mercury vapor pressure vs. the reciprocal of absolute temperature gave a family of straight lines. Each line corresponded to one of the composition: UHg2, UHg3, UHg4, and a saturated solution of UHg4 in Hg. No Mutual solubility of the intermetallics was indicated.

The power and estimated reprocessing load are tabulated for existing and proposed United States and United States-built reactors of 10 Kw or greater thermal power.

Abstract: "An exploding copper wire, one millimeter in diameter, 30 centimeters long, has been developed as a fuse component for a Los Alamos capacitor energy source to be employed in controlled thermonuclear research studies. The fuse allows the passage of the high normal duty "action" (13,700 ampere-coulombs per capacitor) at a 20-second repetition rate. However, it interrupts the circuit to a shorted capacitor in 12 microseconds, thereby protecting the faulted capacitor from explosive energy consumption. The initial phase of the development included observations of various metals (copper, silver, iron, and nickel) as well as various configurations (straight wires, helixes, foils, and tubes). Direct scaling of previous small exploding wire studies at Sandia Corporation was demonstrated with scaling factors up to 700,000."

A test program conducted to develop high integrity piping and seal components for Plutonium Recycle Test Reactor installation. Methods of preventing leakage of costly D2O coolant and maintaining operational safety were investigated.

By using a large central fuel and blanket reprocessing facility, slurry-fueled aqueous homogeneous reactors can attain an estimated minimum fuel cycle cost of 1.4-1.6 mills/kwh; with solution-fueled two-region reactors, a doubling time of 14 years may be obtained at a fuel cycle cost of 2.0 mills/kwh. On-site processing appears desirable only for large power stations made up of reactors designed for short doubling times. For instance, a solution-fueled two-region reactor can attain a 12-year doubling time at an estimated fuel cycle cost of 1.5 mills/kwh at a 2000 Mw electricity station with an on-site processing plant.

The purpose of the Analytical Laboratory Manual is to assemble the basic procedures to be used for the analyses of materials employed within the Fuels Preparation Department. The methods appear in detailed steps suitable for laboratory use. This document replaces the "Essential Material Analytical Manual, " HW-25375 and "Metal Preparation Analytical Manual," HW-30862.

It is being considered that the in-reactor portion of the test section of the PRTR Gas-Cooled Loop Facility consist, in part, of two concentric Inconel-X tubes. The outer tube is the main stress member, with 3.5 O.D. and a wall thickness of 0.065. The inner tube is 3.0 O.D. and has a wall thickness of 0.030. The inner tube provides an annular gas space to serve as thermal insulation.

Abstract: "The cross section for the Be-9(n, t')Li-7*-->Li-7 + Y(0.477 Mev) reaction has been measured in the vicinity of 14 Mev by detecting the gamma-rays at scattering angles from 30 to 150 degrees. A time-of-flight technique was used to distinguish the gamma-rays from the high neutron background. The cross section drops from 20 mb at 13.6 Mev to 10 mb at 14.1 Mev and then rises to 30 mb at 14.7 Mev."

The following is a semiannual progress report, preliminary in nature, covering work done in the period of December 1, 1958 to May 31, 1959.