From the point of view of constituents of a fuel element at temperatures between 2500 and 4500 degree K, the fuel elements can be considered to consist of six types of material: carbon, elements less volatile than carbon, 26 moles of rare gases, 21 moles of alkali metals, 17 moles of alkaline earth metals, and 4 moles of miscellaneous volatile elements. Various processes involving the constituents from 2000 to 45000 degree K are considered. Reactivity gain due to can rupture is discussed.

The maximum temperature in the interior of the fuel element could be greatly reduced by incorporating a liquid between the fuel element and the outer can to increase-heat transfer rates. It is of interest to consider what liquids would be chemically compatible with graphite and the actinide carbides. Elements which melt below 1100 and boil above 1400 deg C that form no stable solid carbides, include Cu, Ga, TI, Ge, Sn, Pb, Sb, Bi, and compounds include GeP, GeS, GaP, Ga/sub 2/S, GaTe, GaAs, SnTe, Sm/sub 3/As/sub 2/, Sb/sub 3/Te/sub 2/, Zn/sub 3/Sb/sub 2/, Zn/sub 3/P/sub 2/, ZnS, ZnTe, and Zn/s ub 3/As/sub 2/. Some of these compounds have equilibrium pressures that might be considered too high, but they may actually vaporize slowly enough because of low vaporization coefficients to make them suitable. There are probably rot enough data nor adequate theories for predicting the rates, and Langmuir type vaporization experiments would be necessary to determine the rates of vaporization of these compounds. The main problem in the use of a heat transfer fluid is that of reaction between the fluid and the actinide carbides. Thermodynamically extensive attack would be expected. However, it may be possible to make the rate …

The quantity and characteristics of fission products in coolant gases due to leaking fuel elements are discussed. It is concluded that the rare gases, the alkali metals, the halides, and Sb may act as permanent gases to a considerable extent. The other fission products are expected to condense out completely on walls or as dust consisting of metals, carbides, and oxides.

From the point of view of predicting melting behavior of fuel elements containing fission products after 50 percent burn-up, the fuel can be considered to consist of 2000 moles Th, 150 moles U, 55 moles of rate earth metal, 31 moles of Zr, 25 moles of Mo, 20 moles of Rh-Ru-Tc, and 15 moles of alkaline earth metal. All other fission products are present in too small amounts to have any important effect upon the melting point or will have vaporized. However, the presence of alkali metal vapor should be considered.

This technical report covers five areas: (1) High-speed computer program; (2) Mathematical methods; (3) ILLIAC use and operations; (4) IBM 650 use and operation; (5) General laboratory information.

The following is taken from ORNL-2257, Instantaneous Velocity Profile Measurement by Photography, by R. E. Lynch, L. D. Palmer, and G. M. Winn. This report is in in preparation status; and errors, inconsistances, and omissions in he language, as well as in the technical aspects, may exist. The technique of using phosphorescent particles to enable photographic determination of qualitative and quantitative instantaneous velocity profiles is covered by AEC Patent Application No. SN-710, 371 issued to F. E. Lynch, L. D. Palmer, H. F. Poppendiek, and G. M. Winn and entitled " A Method of and Means for Visualizing Fluid Flow Patterns.

Standard water treatment practices have proven adequate for scale and corrosion control on the secondary side of the ORR pool-cooling heat exchanger. Corrosion rates measured on specimens exposed to secondary water showed maximum corrosion rates of approximately 1 mpy during the first exposure period and these rates decreased during subsequent exposure.

A preliminary study of dispersing agents for thorium oxide has been completed and several of the dispersants have possible uses. Also many of the industrial dispersing agents tested are not usable with thorium oxide due to induced behavior causing balling and caking. The effects of nitric acid concentration have been observed to also effect each dispersing agent.

Temperatures are given at which two liquid phases form in a synthetic homogeneous reactor fuel solution and its concentrates. The data show a two-liquid-phase boundary temperature of 332°C for the Particular HRT Fuel composition and a flat minimum temperature of 305°C for the initial solution concentrated between 300 and 329°C are presented to indicate solution stability in this temperature region. Some related comments on current HRT operations are given.

The method of calculation of various quantities relating the temperature and the rate of heat removal of UO2 test elements is presented. Graphs of the appropriate quantities as a function of the rate of heat removal are included.

An improved heat sink for space vehicles was proposed in ORNL-CF-59-1-21. Subsequent work on the problem has indicated that there is a substantial probability of a puncture of such a radiator by meteors. To meet this problem a modified geometry has been evolved for which the probability of a meteor puncture should be reduced by a factor of at least 100 relative to the radiator of the original proposal at the expense of an increase in radiator weight of possibly 30%. This memorandum outlines the approach to the problem and a series of similar promising solutions.

Preliminary measurements of the corrosion of titanium were made in 13 M HNO3-0.05 M fluoride using 0.1 M H3BO3 as a liquid and vapor phase complexing agent. Titanium Ax-55 was attacked at average rates of 0.58 and 0.33 mils/month in the liquid and vapor. In dissolver solutions containing 0.5 and 1.0 M titanium, all rates were less than 0.1 mils/month.

Many elements exhibit anisotropic scattering at energies of interest in reactor calculations. A method is presented for the calculation of transport cross sections including the observed anisotropy.

This memorandum summarizes the results of an analysis to determine the extent of displacement of the EOCR core due to blowdown in case of several postulated hot main gas coolant pipe failures. Results show that the core will be damaged for any hot pipe double-ended failure. Excepting the improbable case of no coolant flow existing proper to the break, the core will be damaged for any hot pipe fracture exposing a total flow area to the atmosphere equal to that of one pipe. Smaller breaks will probably be safe in this respect.

Nitrate contained in raffinates from Canadian Blind River mills interferes seriously with thorium extraction by secondary amines. With primary amines, however, the effect is negligible and these compounds are the preferred process extractants.

In certain phases uranium processing it is poss!ble for operating personnel to acquire internal deposits of uranium. This body burden can be acquired by injection, as in contamination of a wound, by ingestion, of by inhalation. In order to estimate internal exposures, some means of determining the location and extent of these internal deposits is essential.

The measured diffusivity of uranyl nitrate in water at 25ºC was 0.7*10^e cm^2/sec with about 40% average deviation. A program was started to develop nonnuclear uses for depleted uranium. Two continuous DRUHM reaction tuns were terminate due to erratic operation of the sodium metering system. In the second Fluorox run with crude UF, which lasted for 29 hr, a total material balance of 94.8% was obtained and 17.9& of the theoretical amount of UF was collected in cold traps and chemical traps.

The referenced memo asked several questions on the operation of the Purex Plant which are of interest to the Eurochemic personnel. These questions are answered below. 1. A qualitative description of the nitric acid recovery systems is desired -- flow of materials, number of pieces of equipment, etc.

The relative neutron capture gamma production in several prospective iron thermal shielding materials for the New Production Reactor was measured to determine the merit of adding boron to the metal. It was found that for the beam geometry the used addition of 1 1/2 percent boron to the iron before casting reduced the soft gamma production by a factor of 6.5 and the hard gamma production by a factor of 10. No attempt was made to measure gamma or neutron transmissions.

Disposal on a specific retention basic of certain radioactive liquid waste solutions emanating from separations from separations plants has been practiced at Hanford since 1944. As used at Hanford, the term "specific retention" is defined as that volume of waste liquids that may be disposed to the soil* and be held against the force of gravity by the molecular attraction between sand grains and the surface tension of the water, when expressed as percent of packed soil volume. In practice it represents the volume of liquid that may be discharged to a disposal pit of known dimensions without leakage to the ground, water, expressed as percent of the total volume of a column of soil with the same cross section as the pit, and extending from the bottom of the pit to the water table. It is recognized that some degree of lateral spreading will occur which has the effect of enlarging the volume of soil contacted by the liquid.

In the field of nondestructive testing the ultrasonic test method is used extensively. In this method ultrasonic energy generated by a transducer is caused to enter the test specimen. The effect on the transducer is cause to enter the test specimen. The effect on the transmission or reflection of the ultrasonic energy by differing test specimen structure is used as an indirect measure of test specimen characteristics.

Since the start of E-metal processing in December, 1958, critical mass control in the Redox dissolvers has been provided by a combination of administrative controls, revised dissolver charging procedures, and new dissolving processes and operation control procedures. These were all based on a maximum allowable charge of E-Metal to the dissolvers which was equivalent to 45 percent of the minimum critical mass.

A series of experiments has been conducted during the past eighteen months with the objective of degerming the accuracy with which precision parts can be duplicated using a castable tooling plastic as a test shape to be reproduced. A precision ground ground 1/4 inch-thick, 90° steel sector of 4'' radius was chosen. The plastics used in the experiments were the die surfacer mixes of the Devon Cooperation and Ren Plastics, Inc. These were selected for use in the test because of their dimensional stability and wear resistance. Ordinary paste type floor wax was used as a mold release. The first series of tests were primarily intended to gain facility in handling this material. After achieving some familiarity with the use of these castable plastics a technique was devised which seemed to hold promise of precision duplication.

Basic Studies. Sinterability studies on the isomorphous system UO2-PuO2 have continued. One-half inch diameter X 3/8'' long compacts containing physical mixtures of the two components have been heated in hydrogen. Sintered density as a function of time and temperature has been determined for times of one and eight hours up to 1600 C. In general, there seems to be minima on isothermal plots of density versus composition in the intermediate range 20-40 w/o PuO2. At concentrations greater than 40 w/o PuO2, density increases rapidly with increasing PuO2. In every case pure PuO2, (produced by decomposing plutonium oxalate at at 300 C) sintered to a greater density that ball ball milled PWR grade UO2. The data, for a one hour soak time, and tabulated in percent of the theoretical crystallographic density, can be seen below: