The initial 30-Mw SRE Core III loading will contain a total of 33 fuel elements. Of these, the central 7 fuel elements are test elements and the remaining 26 are driver elements; 4 of the 7 test elements are designated as standard test elements. These elements are identical to the driver elements with the exception of the active fuel length. The remaining 3 test elements are designated as special test elements and incorporate fuel rods of smaller diameter and increased enrichment to obtain higher burnup rates, greater specific power, and higher fuel temperatures. Geometry design data for the various elements considered in the analysis was obtained from Dwg. No. 650 deg F, the mixed-mean coolant outlet temperature for the core at 1200 deg F ( plus or minus 15 deg F), the maximum average temperature on the cladding at 1275 deg F, and the maximum fuel temperature in the range of 2000 to 2100 deg F. The thermal performance of the fuel elements was analyzed with the SORTD code and the Heating code. The results of the analysis are presented in tabular form. Axial temperature profiles are also presented for representative fuel elements. The core outlet coolant mixed-mean temperature was …

The outgassing characteristics of specimens of the EGCR moderator graphite stock were determined in vacuo to a maximum temperature of 1000 deg C using external resistance heating and to 1800 deg C by induction heating. The specimens examined were cut from several locations in two of the 18-in. x 18-in. x 20-ft graphite bars which had been prepared under fabrication conditions comparable to those used for the graphite columns present in the Experimental Gas- Cooled Reactor. Data are given which show the effect of the position of sampling of the bars on the density of the graphite. The volume and composition of desorbates obtained at 300, 600, and 1000 deg C as a function of specimen size and position of specimen within the bars also are given. The volume-time relationships at 300 and 600 deg C can be expressed satisfactorily by v = A log t + B over extended intervals of time. A linear relationship prevails at 1000 deg C only after heating for longer than approximates 800 min. The volume and composition of the desorbates obtained at 1000, 1400, and 1800 deg C using induction heating are tabulated. (auth)

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A hybrid approach was adopted in the use of an on-line computer in setting up and analyzing nuclear physics experiments. In addition to the usually cited advantage of online flexibility and the ability to do off-line calculations, the general purpose computer can simulate data by preserting the results of off-line calculations to the experimenter in a format identical to that used for data display. As compared with off-line calculations at a computer center with subsequent hand or machine plotting, the use of the build-in display hardware provides a more convenient comparison of theory with experiment, as well as greater ease and speed. The advantages of on-line data transformation are preserved without accompanying limitations on the rate of data taking. The data from the experiment consisted of energy correlations in two-particle coincidence experiments. The loci of points in energy-energy space fulfilling energy and momentum conservation were calculated, displayed, and photographed before each experimental run. Interpretation of the experimertal data was assisted by modulation of the loci (of the number of counts per channel) according to the predictions of various models. (auth)

A survey was made of the literature which was published on the reduction of plutonium compounds to plutonium metal between 1950 and April 1963. This report is a summary of the information which was gathered during the survey. (auth)

The thermal and hydraulic core parameters were determined using the SORTD I code for 90% ThO/sub 2/, 10% UO/sub 2/ fuel both for (1) a core containing 592 fuel elements corresponding to the UC reference core with a maximum UC temperature of 2000 deg F and (2) a core containing 784 fuel elements corresponding to a UC core with a maximum UC temperature of 1750 deg F. Eighteen rod elements with 2.5 in./sup 2/ and 3.5 in./sup 2/ fuel areas, and 30 rod elements with 4.5 in./sup 2/ and 5.5 in./sup 2/ fuel areas are analyzed for 8 cases. (auth)

Report documenting the progress of the Army Gas-Cooled Reactor Systems Program to develop a mobile nuclear power plant for military field operation.

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A compound decision problem is the simultaneous consideration of a large number of statistical decision of identical nature. The work of Hannan and Robins are extended to the derivation of optimal asymptotic procedures in the sense of regret risk convergence for a variety of compound decision problems. Convergence theorems are derived. (D.L.C.)

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Thesis submitted to Univ. of Tennessee, Knoxville. Statistical methods were used in an attempt to determine the effect of the tendency to report accidents on the systemic variance in minor injury data over a 6-yr period. The population surveyed included 245 journeymen of 9 skilled craft groups continuously employed during the period. Results indicate that injury and non- injury visits to the dispensary were relatively stable during the 6-yr period and that there was a significant positive relation between non-occupational and injury visits during the period of study. (C.H.)

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The corrosion of 8081 and X-8001 aluminum alloys and the resultant formation of an adherent corrosion product on the corroding surface were investigated under conditions (except radiation) comparable to those that will exist on the surface of fuel-element cladding during operation of the Advanced Test Reactor. Since previous experiments indicated that corrosion penetration of the aluminum clad was unlikely during a reactor cycle provided the water chemistry is properly controlled, most of the studies in this investigation were concerned with the effect of variables on the rate of formation of corrosion- product films. These films have low thermal conductivity and can be a major factor in producing high fuel-element temperatures which lead to fuel-plate instabilities. The experimental procedures were the same as used in a similar study for the High Flux Isotope Reactor, but the ranges of variables investigated were greater than in previous studies. The 6061 and X-8001 alloys corroded to the same extent under the same test conditions until the corrosion product (boehmite) that formed on the surface bccame thick enough to spall spontaneously from the surface, usually about 2 mils thick. Spallation from the surface of the 6061 alloy was always accompanled by localized attack of the …

The development of instruments for controlling reactor operation is reported. A shim-scram actuator was designed incorporating an electromagnetic dnlve for shim and scram, a shim speed limiting device, and a force feedback position indicator. A three-channel trip circuit and a two-out-of-three logic circuit using controlled switches in place of transistors was designed, built, and tested. A capacitance-type temperature sensor was operated in an inert atmosphere at temperatures up to 3782 deg F. Models of a gridded and a compensated a-c ionization chamber were tested in both thermal neutron and gamma environments. The compensated a-c ionization chamber demonstrated better than 98% gamma compensation at a thermalneutron flux of 5 x 10/sup -11/ nv and 1 Mw reactor power. Unpowered charged-fragment neutron detectors using boron-10 or uranium-235 as the emitter coating were demonstrated to respond linearly to changes of thermalneutron flux. Potentials, developed within the detecting circuit, possibly due to contact potentials, are suspected to be the cause of detector output-current instability as a function of time. Fission counter operation at 816 deg C was demonstrated to be feasible, but operation was not entirely satisfactory. Adequate reactor power range neutron sensing to 535 deg C is feasible using uncompensated d-c ionization chambers. …

The deviation from the expected coolant flow distribution within the SNAP 2 reactor is due to the filling and draining of the unfed'' peripheral flow channels. An analysis of the cross-flow in a simulated SNAP 2 model omitting the unfed'' peripheral channels was made. The results of this investigation are presented herein. (auth)

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During this period, continued effort has been placed on the fabrication of high burnup irradiation test specimens, on additional UO2-PuO2 and PuO2 sintering, on oxygen diffusion and thermal expansivity measurements using UO2-PuO2, and on the preparation of reproducible PuO2 powder.

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The equations and procedures of the PTD-1 program for obtaining the surface temperature distribution, the gas bulk temperature, and the pressure distribution for any of the 234 channels in the EGCR are developed. The program, in FORTRAN for the IBM 7090, is designed for any arbitrary power distribution yielding a constant gas outiet temperature or a given maximum surface temperature and includes the effects of thermal radiation on surface and bulk gas temperatures. The flow sheet and some results are included. (auth)

The computer program FATT for calculating the transient temperature distribution in the EGCR core is described. The program, in FORTRAN for the IBM 7090, provides an arbitrary choice of axial increments for the reactor core. The heat transfer coefficients are made temperature-dependent. Provisions are available for plotiing the results from the program on the Calcomp plotter. The equations and some typical results are included, and the finlte difference method of solution is described. (auth)

Differential cross sections for elastic {pi}-p scattering have been measured at eight energies for positive pions and seven energies for negative pions. Energies ranged from 310 to 650 MeV. These measurements were made at the 3-BeV proton synchrotron at Saclay, France. A beam of pions from an internal BeO target was directed into a liquid hydrogen target. Fifty-one scintillation counters and a matrix-coincidence system were used to measure simultaneously elastic events at 21 angles and charged inelastic events at 78 {pi}-p angle pairs. Events were detected by a coincidence of pulses indicating the presence of an incident pion, scattered pion, and recoil proton and the results were stored in the memory of a pulse-height analyzer. Various corrections were applied to the data and a least-squares fit was made to the results at each energy. The form of the fitting function was a power series in the cosine of the center-of-mass angle of the scattered pion. Integration under the fitted curves gave values for the total elastic cross section. The importance of certain angular-momentum states, particularly the D{sub 13} state near 600 MeV, is discussed. Several possible explanations are given of the enhancement in the {pi}{sup -}-p cross sections near 600 …

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