Description of cooling, shielding, controls are discussed for 100 kw and 1 Mw operation of a low cost experimental neutron chain reactor.

Equilibrium krypton and xenon adsorption isotherms were obtained for four varieties of charcoal and for Linde Molecular Sieves Types 4A and 5A, generally at 0, 25, and 60°c. Such data are of interest in connection with design and evaluation of adsorbers for radioactive noble gas fission products. The isotherms were fitted, by linear regression analysis, to straight-line forms of the Freundlich and Langmuir equations. The Freundlich linear equation gave the better fit and the parameters of this equation are presented for each of the isotherms. Also presented are the constants for an equation representing the temperature dependence of arbitrary adsorption coefficients, the coefficients having been calculated from the Freundlich isotherm parameters. Some aspects of the applicability and accuracy of these results are discussed.

This report is presented in order to provide a satisfactory system of symbols and identifications for process-instrumentation equipment and to promote a uniformity of practice that will simplify and expedite instrumentation work. It is intended that the systems presented here should be capable of designating and identifying the multitude of instrumentation items which are used for control and operation of conventional processes, as well as for specialized work peculiar to ORNL. Instrument Society of America standards have been adhered to whenever practical.

Oscillations have been observed in a magnetically supported cylindrical rod of plasma. This rod of plasma can be the discharge occurring in the defining aperture of a Mode II, pressure gradient arc. Similar oscillations can also occur in the column of a Mode I arc. These oscillations appear to be the mechanism that drives the Mode II blowup phenomena.

Results of the examinations of corrosion specimens exposed in the HRT are presented. Specimens examined included (1) core screen samples, (2) core specimen array No. 1, (3) blanket specimen array No. 2, (4) core solution line specimen arrays No. 103 and 103A, (5) blanket solution line specimen array No. 203. Complete information is still not available on all the specimens removed from the reactor, however, those data which have been accumulated are presented. These include corrosion rates, computed from specimen weight-changes, and results of chemical analyses of scales removed from the specimens or specimen holders. Also included in the report is a summary of the HRT operating schedule during exposure of the specimen and of the status of examinations for those specimens removed from the reactor prior to run 20.

Report issued by the Oak Ridge National Laboratory discussing semiannual progress made by the Instrumentation and Controls Division. Descriptions of progress and studies conducted are presented. This report includes illustrations, and photographs.

Technical report detailing expansion of the Aircraft Nuclear Propulsion at the Oak Ridge National Laboratory. Major facilities completed at this time were the Shielding Rector, the ANP Critical Facility, and the 86-in. Cyclotron. Outlines further need for radiation damage studies. [From Summary]

Report issued by the Oak Ridge National Laboratory discussing quarterly progress made by the Homogeneous Reactor Program. Descriptions of progress and studies conducted are presented. This report includes tables, illustrations, and photographs.

Report issued by the Oak Ridge National Laboratory discussing quarterly progress made by the Homogeneous Reactor Program. Descriptions of progress and studies conducted are presented. This report includes tables, illustrations, and photographs.

Further calculations have been made to determine the desired radial fuel distribution in the HFIR and in the forthcoming HFIR critical experiment. In the process the design of the core was changed to include a 1-cm-thick annular space of water between the two nearly equally thick fuel annuli, a metal-to-water ratio in the fuel annuli of 1.0 (0.050 in. thick plates and coolant channels ) was specified, and the active length of the core was increased from 18 to 20 in. Results of the calculations indicated that the largest ratio of maximum meat thickness to minimum meat thickness occurred in the inner fuel annulus and was equal to 3.6, while the maximum fuel concentration occurred in the outer fuel annulus and was equivalent to about 0.7 g of U-235/cm^3 of meat. The total U-235 loading for this core was 8.01 kg, which results in a core lifetime of about 14 days.

A simplified method was developed for calculating wall-scatter gamma radiation escaping through a shield opening. The method was applied to the HRT and the results showed that next to the line of sight contribution, scattering of the wall of the shield opening was the main contribution to the dose at the rear edge of the shield. Design charts were prepared that give the dose as a function of the gamma source location with the reactor cell.

The countercurrent gas-liquid system BF3(g)—anisole·BF3(l) for the concentration of boron isotopes has been studied. The single-storage separation factor varies from 1.039 at 0°C to 1.029 at 30°C. Rate of exchange is rapid, and, with efficient contacting equipment, complete exchange may be obtained in less than 15 sec. A total separation of 1.525 has been realized in laboratory equipment. The critical-product reflux reaction is quite efficient. Only about 55 moles of BF3 remain in each million moles of effluent solvent under laboratory conditions. The vapor pressure of BF3 over the complex rises sharply as the temperature is increased. At 0°C the pressure is 150 mm Hg, and at 40°C the pressure has risen to 1800 mm Hg. From vapor-pressure measurements, an approximate upper limit of ΔH= -12kcal per mole of complex was calculated for the reaction [equation not transcribed]. Qualitative tests indicate good resistance of anisole to decomposition by BF3 under plant conditions. The uncatalyzed exchange of boron between BF3 and BCl3 was found to be too slow to be exploited in a countercurrent system. The single-stage, equilibrium separation factor for the Nitrox system is a function of acid concentration. At 26°C the factor ranges from 1.064 with 1 M acid …

Report issued by the Oak Ridge National Laboratory discussing the Research Reactor (ORR). General descriptions of the ORR are presented. This report includes tables, and illustrations.

The fact that material transport does occur under conditions of finite temperature difference in a flowing molten metal system was established. The rate mass transfer was thought to be either diffusion limited or solution rate limited. It is believed that the mass transfer of structural materials in Na or NaK systems is solution rate limited. The limiting process has not been qualitatively or quantitatively confirmed for the Inconel-Na or Inconel-NaK system. Increasing the maximum system wall temperature increases the amount of mass transfer, at least above 1300 deg F. The effect of the total temperature difference across the system on the amount of mass transfer was determined.

Technical report describing the tests on types 309, 316, and 347 stainless steel. These steels were tested for a total of 779 to 828 hours in three different synthetic waste solutions. Results shoe that the best all-around corrosion resistance to the test conditions was exhibited by 316 stainless steel, but in one solution 347 stainless steel was more resistant. [From Abstract]

One of the considerations in designing a flat plate fuel element is the resistance of the fuel plates, especially the outer plates in the fuel plate array, to deflection and permanent deformation as a result of pressure differentials. An investigation was recently initiated wit the objective of obtaining preliminary information on the APPR-type fuel element to determine the effect of pressure differentials on the outer plates in the fuel assembly. The APPR-1 fuel element consists of 18 flat composite stainless steel fuel plates, joined to grooved 50 mil thick type 304L stainless steel side plates by brazing with Coast Metals N. P. alloy.

The IBM-70% code GHT has been programmed for the 7090computer, to be run under control of the IBM-7090 FORTAN Monitor System. By eliminating the use of tapes for intermediate number storage, it has been possible to reduce computing time by a factor of 26 over the 704. A minimum of three tapes are required; one for input, one for output, and the System tape. One scratch tape is required for transient problems, and one punch tape is required if the steady-state temperature distribution is to be punched on cards.

Technical report outlining the rate of production of modified MTR type fuel elements for the Bulk Shielding Facility has proceeded. Includes compatibility test that were started as a guide in the selection of materials suitable for fuel-element fabrication. [From Summary]

Analytical expressions were obtained for the time behavior of fuel concentrations and fuel-feed rates in single-region, spherical, UO3-ThO2-D2O reactors.

From introduction: "The work described in this report was carried out as part of the feasibility study (ORNL-117) of a supercritical water reactor (SCWR) for use in nuclear propulsion of aircraft. The object of this work was to study the dynamic behavior of a particular design of supercritical water reactor. Numerical results are presented in Appendix I."

A program translates an algebraic language like Algol into the machine language of an electronic computer must perform the following functions.

Calculated data and graphs describing the effects of continuous thermal-neutron irradiation of thorium, the usual method of operations of homogeneous reactors, are presented.The buildup and decay of U^233, Pa^233, other heavy isotopes, and fission products are considered on the basis of best available cross-section and fission-yield data. The effects of the heavy isotopes and fission products on neutron economy are discussed.

The measured pressure drop across the reactor core, with the sample holder in place, is 6.9 psi, more than twice the estimated value. Better estimates, based on more rigorous mathematical analysis, should be possible for future problems of this type. The 2% density difference which produced the relatively high velocity of approximately 1 fps, in this experiment, will result from a temperature difference of about 8 C. It is concluded that the bulk fluid temperature near the sample holder will be less than 8 C above the average temperature at the same elevation in the core.

This report considers the HFIR reflector design criteria and presents a summary of the reflector design. The reflector type chosen as complying best with the established criteria consists of a 3 in. thick removable beryllium annulus utilizing four concentric cylinders with cooling water flowing through the annuli between cylinders, and an outer 9 in. thick permanent beryllium annulus with axial circular coolant holes. Reflector support structures and experimental facilities are described and probable beryllium replacement costs are indicated.