Hanford uranium contains minute angular inclusions which affect the microstructure, reactivity, and other important factors controlling the serviceability of the metal. Small quantities of the inclusions have been isolated by chemical means, and the x-ray diffraction patterns and chemical analyses of the isolated materials have been determined. As a first step in the identification of the inclusions present in rolled uranium, a search was made for a chemical method of separating the inclusions from the matrix metal.

The construction and operation of a fission gas generator, containing about 25 grams of uranium in the form of a powder with a high specific surface, are described in detail. The purpose of the work discussed in this report was to examine the feasibility of producing, separating, and assaying samples of Xe135 in preparation for a proposed measurement of the neutron cross section of this isotope. Krypton and xenon are separated by selective adsorption on charcoal at reduced temperature while iodine is removed by charcoal sorption at room temperature.

The Hanford Remote Pipetter has developed into a very useful tool for routine pipetting by semi-skilled non-technical personnel. Radiation exposure to the operators has decreased to normal background levels as proper shielding exists between the sample and the operator. The results achieved by the pipetter have demonstrated its flexibility and simplicity of operation.

Report from Hanford Laboratories concerning "the design and construction of the 100-N Reactor and heat dissipation plant complete with the necessary auxiliaries" (p. 2). Details of its construction and the plant's systems and instrumentation are described as well as economic considerations.

Review of previous work is presented in addition to the results of recent studies concerning loss of primary coolant when the system is cold and pressurized and the problem of supplying adequate cooling following the injection of light water.

This report describes the development of an ultrasonic instrument for resin level measurements in an ion exchange column.

Specifications including detail dimension, materials, fabrication steps, acceptance criteria, and final assembly steps for the swaged uranium dioxide, 19-rod cluster Plutonium Recycle Test Reactor fuel element.

Report presenting research and development activities in the field of radioactive wastes. This particular report is concerned with the fixation of radioactive residues when the failure of a pot liner destroyed the furnace.

Investigation of principles of pulse-column design and effects of operating variables.

Chain reacting conditions for plutonium nitrate in water solution have been examined experimentally for a variety of sizes of spheres and cylinders.

Basic information on the design of the Knolls Atomic Power Laboratory (KAPL) -120 loop.

An electromagnetic eddy current instrument is described that is capable of measuring copper and nickel plating 1 to 8 mils thick plated on bismuth mandrils of various sizes and shapes.

Describes the design criteria, design details, and final installation of a high precision temperature and intimate contact monitor.

Graphs for estimation of plutonium and trans-plutonium isotopic content of irradiated plutonium reactor fuel of various initial isotopic compositions.

Plutonium Oxide Fuels. Mixtures of PWR grade UO2 containing 10, 20, 30, 40, 50, and 60 w/o PuO2 were sintered in hydrogen for 44 hours at 1600 C to get additional data on solubility in this system. Densities of all the pieces were low, approximately 80 percent of theoretical; however, solid solution formation was complete in every case. The low density material should not affect lattice parameter values, but it did slightly reduce the intensity of the reflections.

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 ambient temperature of the Columbia River is of interest to the Aquatic Biology Operation since it provides a basis for controlling the temperatures in various experimental tanks which contain Columbia River organisms and since it provides some indication of whether conditions are favorable for the valuable species of fish living in the river. Since the start-up of the plant, temperatures of the river water have been taken in the several water treatment plants.

Basic Studies. It has been reported previously that mixed crystals of PuO2 and UO2 have a higher sintering rate than UO2 alone. However, results to the contrary were obtained on addition to 1/4, 1/2, 1, 2, 5, and 10 w/o PuO2 to PWR grade UO2. Pellets of the above concentrations were heated for one hour in hydrogen at 100 C intervals from 1000 to 1600C.

Two Zircaloy-clad capsules (GKH-14-19,20) containing two compacts each of high density PuO2-UO2 mixed crystal oxides were shipped to the MTR in December 2, 1958. The compacts contain 0.026 a/o PuO2, have densities of 91 percent of the theoretical value, and will generate the same specific power as an Al-1.8w/o Pu alloy rod of the same diameter would produce. Two capsules (GKH-14-21,22) have been prepared and contain three compacts each of low density, about 65 percent of the theoretical value, PuO2-UO2 mixed crystal oxides. It is tentatively planned to ship the last two capsules during January 1959.

PuO2-UO2 Irradiation Capsules. Four capsules of Zircaloy-clad, sintered PuO2-UO2 mixed crystal oxides in a UO2 matrix are awaiting irradiation in the NTR.

The PRTR pressure loop is an experimental facility to be installed in the Plutonium Recycle Test Reactor, Building 309, for use in testing the feasibility of reactor cooling systems utilizing high pressure water or steam as the coolant. It will furnish operating experience with such systems and serve to test fuel elements and components designed to operate in such environments.

A series of tests conducted in an attempt to reduce the observed O2 content of primary recirculation loop water to a value of <0.14ppm by the current loop method which is a combination of pressurizer degasification and venting flow.

Basic Studies. Sinterability experiments in the system UO2-PuO2 have continued, and data are available at one hour hold times across the UO2-PuO2 composition limits. Sintered densities appear to be markedly dependent on pressed densities with densification occurring very rapidly at higher pressing pressures. The following table illustrates the effect of one hour at temperature on final density for pure plutonium dioxide pressed to both 40 and 60 percent of theoretical density.

The fabrication processes applied to nuclear fuels are subject to severe limitations because of the conditions imposed by the reactor environment. The combined problems of neutrons fluxes, high heat fluxes, corrosion by the coolant , and embrittlement by hydriding or similar reactions may be minimized through establishing rigorous materials and fabrication specifications for fuel and cladding.