A formulation is developed to study reactor power capability based on the likelihood of incipient centerline fuel melting. Attention is also directed to the proper definition of this likelihood. As a consequence, it is shown how to compute the total probability for fuel melting as well as the expected number of fuel pellets and the associated variance. Factors considered include statistical variations in pellet fissile densities, gap sizes, coolant temperatures, reactor power, and the power-to-melt function. General formulas suitable for computation are given along with more transparent analytical results.

Drying of Amberlite IRC-72 ion exchange resin in a fluidized bed dryer was investigated. Resin water content was measured as a function of drying time for various drying temperatures, bed loadings, and air flow rates. An incomplete equation for the induction period and complete model for constant rate drying were developed. Further development of an induction period model requires installation of an accurate air flow measurement device. A drying temperature of 200/sup 0/F results in the shortest drying time with no resin damage. Optimization of the process with regard to other process parameters requires development of a complete drying model. (auth)

Twenty-four separate gas fields producing from geopressured sands have been identified in the South Texas area that includes Hidalgo, Cameron, Willacy and the lower half of Kenedy Counties. Of these, twenty are in Hidalgo County. Geological study and detailed investigation of reservoir parameters in each of the fields have been accomplished. Two areas in particular are discussed in some detail in this paper: the Vicksburg Trend on the west, represented by McAllen Ranch Field, and the south central Frio-Vicksburg delta, including the McAllen-Pharr-Edinburg area. The depth of the geopressured zone in the study area ranges from 7,000 feet in western Hidalgo County to 12,000 feet in the central Cameron County. Temperature data within the fields, corrected to equilibrium values, yields a 300/sup 0/F isogeothermal surface at depths of 10,500 feet to 14,000 feet over the study area. The most critical reservoir parameter was found to be the effective permeability in all the fields in the region. Permeability values ranged from 0.03 md to 8.0 md, with average values over all the fields near 1.0 md. A permeability profile of McAllen-Pharr shows permeability there to be an inverse function of depth, with effective permeability values from 16 md above the geopressured …

An iridium-clad, 100-W /sup 238/PuO/sub 2/ sphere, a prototype for the multihundred-watt radioisotope thermoelectric generator, was exposed for 1 y to a simulated temperate humid climate in an environmental test chamber containing sandy soil. The hot sphere sank into the soil after the first rain, then gradually acquired a hard crust around it as a result of the rainwater reacting with the hot soil during successive rains. Time and temperature profiles of the sphere were recorded during the weekly rains, and the air and rainwater that percolated through the soil were monitored for plutonium. No plutonium was released from the sphere. Aside from the crust formation, very little reaction occurred between the hot iridium shell and the soil.

Summarized is work on the structure of transition metal ion-containing silicate, borate, and other insulator glasses. Raman spectra were measured on lead silicate and on alkali-alkaline earth nitrate glasses. Raman spectra of lead silicate glasses are strongly polarized. The high frequency modes are greatly broadened with respect to alkali silicate glasses and new features appear in the low frequency region related to the lead concentration. The nitrate glass Raman spectra show broadened bands in more or less the positions expected from the molecular modes of the nitrate ions. The broadening and some splitting of these bands can be interpreted in terms of a distribution of local fields around the nitrate ions. An extensive series of chromium-containing silicate and borate glasses were prepared. Chromium appears in both Cr/sup 3 +/ and Cr/sup 6 +/ states. The Raman spectra show that hexavalent chromium exists in the glasses as molecular chromate or dichromate-like clusters. Cr/sup 6 +/ is not incorporated into the network. The local environment of Cr/sup 3 +/ was investigated by optical absorption and luminescence spectroscopy. The optical properties of Cr/sup 3 +/ in silicates were largely independent of base glass composition, which is not true of the borates. A study …

State-of-the-art approaches for the calculation of gamma heating in LMFBR core, blanket and reflector regions have been evaluated, with particular emphasis on coupled neutron-gamma methods/cross section sets. The major source of calculational error was found to be the apparent failure to impose a mass-energy balance on total gamma energy yield from neutron capture and other interactions in the preparation of representative neutron-gamma cross section sets. The applicability of many simplifying assumptions was demonstrated, including: volume-weighted homogenization, insensitivity to the shape of the gamma-source-spectrum, gamma energy deposition equal to gamma energy source more than 10 cm inside large zones of uniform composition, and the negligible effect of bremsstrahlung. A simple one-group method was developed to permit rapid, accurate estimation of the large (factor of 2) changes in the gamma energy deposition-to-source ratio possible near region interfaces. The approach, which also ensures conservation of mass-energy, was used in conjunction with coupled neutron-gamma computations to verify that previous experimental measurements of gamma heating in an LMFBR blanket mockup at M. I. T. were in accord with theoretical expectations within the experimental precision of +-10%.

The linear thermal expansion of stoichiometric /sup 238/PuO/sub 2/ was measured over the range 25 to 1600/sup 0/. The value of ..delta..L/L/sub 0/ per degree C, calculated from the data, is ..delta..L/L/sub 0/ = -2.249 x 10/sup -4/ + 9.020 x 10/sup -6/T - 1.130 x 10/sup -9/T/sup 2/ + 1.525 x 10/sup -12/T/sup 3/.

Recent forecasts of total electricity generating capacity and energy demand as well as for electricity produced from nuclear energy and hydroelectric power are presented in tables and graphs to the year 2000. A forecast of the distribution of type of fuel and energy source that will supply the future electricity demand is presented. Use of electricity by each major consuming sector is presented for 1975. Projected demands for electricity in the years 1985 and 2000, as allocated to consuming sectors, are derived and presented.

This report, the seventeenth of a series, is a compendium of monthly progress reports in support of the increased utilization of coal as a source of clean energy. The projects reported include those for hydrocarbonization, solid-liquid separations, chemical research and development, engineering evaluations of nuclear process heat for coal conversion, engineering evaluations of the hydrocarbonization and synthoil processes, and coal-fueled MIUS. Two more runs were completed with the bench-scale hydrocarbonization research system using nitrogen at 20 atm with the preheater at 1400/sup 0/F and the reactor at 1250/sup 0/F. Some difficulty was encountered with the coal feeder and corrective modifications are underway. Revisions and additions were made to the flowsheet for a plant using direct steam gasification of coal, which is thermally driven by a 3000-MW(t) VHTR. In the engineering evaluations work for the synthoil process, flow diagrams for four units were finalized. A preliminary facility site plan was developed. Conceptual design of the solids-liquid separation plant specifying centrifugation followed by filtration of the thickened underflow was completed. In the MIUS program, a /sup 1///sub 12/ scale model of the latest layout is being constructed. (auth)

Progress is reported on research projects in the fields of radiation protection, industrial hygiene, instrument development, fire safety, decontamination, and environmental protection. (HLW)

In the structural design of LMFBR components for elevated temperature service it is necessary to take account of the time-dependent, creep behavior of materials. The accommodation of creep to assure design reliability has required (1) development of new design limits and criteria, (2) development of more detailed representations of material behavior, and (3) application of the most advanced analysis techniques. These developments are summarized and examples are given to illustrate the current state of technology in elevated temperature design.

Preliminary experimental information for beta-ray energy release from fission product decay following thermal-neutron fission of /sup 235/U has been obtained for cooling times between 3 and 14,400 secs. The data were obtained as pulse-height spectra for beta energies between 0.25 and 8 MeV using a two-crystal scintillation spectrometer, and were unfolded to give beta-ray energy spectra of moderate resolution. Two irradiation times, t/sub i/ = 2.4 and 100 sec, were studied. The energy release data were studied. The energy release data were obtained by integrating the observed spectra and then estimating the contribution for E/sub ..beta../ less than 0.25 MeV. Difficulties encountered in this first experiment using the beta-ray detection equipment are discussed. Previously reported preliminary gamma-ray spectra have been compared with spectra calculated using spectral information in the ENDF/B--IV data file for approximately 180 fission products. Several comparisons are presented for t/sub i/ = 100 secs. As expected the comparison is not very good for short cooling times, but is encouraging for t/sub cool/ approximately 2000 secs.

The laser Raman scattering analysis of combustion flames requires a knowledge of the scattering cross sections for a variety of molecular species. Since cross sections are known for only the most common and most stable of molecules (e.g., N/sub 2/, O/sub 2/ and H/sub 2/), a program to calculate cross sections for other molecules of interest to combustion analysis has been initiated. In this paper theoretically-determined cross sections for H/sub 2/, N/sub 2/, OH, LiH, and O/sub 2/ are presented. Comparison with the few experimentally determined cross sections indicates that the theoretical approach is a reliable method for determining Raman scattering cross sections for those molecules whose cross sections cannot be readily determined experimentally. (auth)

The experimental procedure for irradiating the above specimens is given. No results are presented. (MOW)

Separate abstracts were prepared for 16 sections of this report. A list is included of 21 publications during the time period covered. (CH)

In separations of solids from liquids by filtration, the motion of liquid is customarily normal to the filtering surface, and solids are left on the filter. In a variation called cross-flow filtration, liquid is pumped parallel to the filtering surface. By this device, thickening of flux-limiting filtercake is slowed, and the original stream is separated into a large volume of filtrate and a concentrated slurry of solids. Results reported here were obtained in cross-flow filtration used as an element in physical-chemical treatment of municipal sewage, mostly with the effluent from primary settling, but in some cases, with clarified activated sludge effluent as feed. Filtrate from passage through fabric tubes (1-inch fire-hose jackets) of primary effluent, treated with iron or aluminum salts, with powdered activated carbon (PAC), or with both hydrolyzable ions and PAC, was generally of quality superior in turbidity, organic carbon and other respects to the effluent from biological secondary treatment. Effects on product quality and flux of pressure, circulation velocity, additive concentration, water recovery, pH and other variables were investigated. Based on production rates obtained, estimates of treatment costs were made.

Light water reactor safety activities performed during July through September 1975 are summarized. The isothermal blowdown test series of the Semiscale Mod-1 test program has provided data for evaluation of break flow phenomena and analyses of piping flow regimes and pump performance. In the LOFT Program, measurement uncertainties were evaluated. The Thermal Fuels Behavior Program completed two power-cooling-mismatch tests on PWR-type fuel rods to investigate critical heat flux characteristics. Model development and verification efforts of the Reactor Behavior Program included development of the SPLEN1 computer code, subroutines for the FRAP-T code, verification of RELAP4, and results of the Halden Recycle Plutonium Experiment.

The numeric and text processor of the MASTER CONTROL (MCP) data-base-management system permits the user to define fields and arrays that are functionally dependent on the data retained in a data base. This allows the storage of only the essential and unique information and data, and the calculation of derivable quantities as required. The derived quantity can be expressed as an arithmetic expression, that is, a functional relationship. Functions can be multiply subscripted and can be embedded within other functions at up to 58 levels. They can be stored either semi-permanently in a repertoire of functional relations, or they can be defined interactively from a terminal and used immediately for searching on the derived value. The processor also permits the conversion of literal strings into numbers, and vice versa. In addition, the user can define dictionaries that allow the expansion of keyed sentinels associated with records in the data base into fully descriptive expressions. This option can be used for cost-effective searching and data compaction. The functional definitions are reduced to Polish notation and stored in a disk file from which they are either retrieved on demand and evaluated according to the data of records specified or used in any …

An investigation of the densification of precompounded powder of the A15 phase Nb/sub 3/(Al,Ge) was made. The influence of various parameters such as additives, temperature, pressure and time in sintering of this material was studied. Since cold pressing followed by sintering did not produce sufficient density, the hot pressing technique was used. By hot pressing at 1450/sup 0/C for /sup 1///sub 2/ hour under 6 ksi pressure, about 95 percent densification was achieved. Results provide information that could lead to the development of a viable process for producing superconductors based on this compound. 14 figures, 17 references.

A review of current programs to develop superconducting power transmission shows that current plans require helium refrigerators operating at 5 to 13/sup 0/K and 3 to 15 atm pressure with compressor power input in the range of 1,300 to 3,500 HP. Future requirements will probably trend toward slightly higher temperatures and larger refrigerators. Present large helium refrigerators and APCI standard nitrogen plants were studied and an average outage frequency of about 18 per year is found to be typical for both. Cost and reliability studies of alternate refrigeration systems based on studies of components shows that the best current system which would have a failure rate of once in 20 years would consist of two full size oil flooded screw compressors in parallel, manifolded to two full size cold boxes and a liquid helium back up dewar. The principal area of development needed to implement this system is in the switch over mechanisms. These include switching to an auxillary power source in the event of power interruption, switching to the standby compressor, and switching to the back up liquid helium dewar. Costs are projected as being only slightly greater than preliminary estimates.

Ionization equilibrium calculations are carried out for iron ions at a density of 10/sup 12/ cm/sup -3/ in a (hydrogen) plasma with electron density 10/sup 14/ cm/sup -3/, at temperatures from 0.8 to 10 keV. The computed radiated power loss from this plasma due to the iron ions ranges from about 4 W/cm/sup 3/ at the lowest temperature to about 0.4 W/cm/sup 3/ at the highest temperature; loss rates for other electron and ion densities will scale approximately as N/sub e/N/sub Fe/10/sup 26/. The losses are due principally to collisionally excited line radiation (especially ..delta..n = 0 transitions) at low temperatures, and to collisionally excited ..delta..n not equal to 0 transitions and to continuum radiative recombination at high temperatures. Spectra are also computed for diagnostic x-ray K/sub ..cap alpha../ (1s - 2p) transitions; the change in spectral distribution as a function of temperature agrees well with observations in the ST Tokamak. Bound-bound radiative transitions and dielectronic recombination are discussed at length in appendices; the latter process is of great importance in the establishment of ionization equilibrium, and in the excitation of K/sub ..cap alpha../ radiation at the lower temperatures.

Measurements were made of the neutron spectrum produced by bombarding a thick beryllium target with 30-MeV deuterons at the University of California, Davis cyclotron. This spectrum is of interest in studying the effect of neutrons on materials to be used in future fusion reactors. The spectrum was inferred from the activation of two sets of detector foils placed at 0/sup 0/ to the deuteron beam, one immediately behind the beryllium target block, and one 40 mm to the rear. A least-squares program was used to analyze the foil activation data to obtain the fluence in each of seven energy groups. The neutron spectrum (fluence/MeV) close to the target decreases continuously with energy in the range 5-32 MeV, while the spectrum 40 mm back has a peak at about 13 MeV. The contribution from neutrons of energies less than 10 MeV is much greater than that found in previous spectral measurements made at large distances from the target. This difference is attributed to the neutrons which are emitted at large angles from the deuteron beam. These observations show the importance of evaluating the neutron spectrum near the target if samples of materials are to be irradiated in this location. (auth)

Acid-Thorex flowsheets using tributyl phosphate (TBP) to process feed which simulated that from HTGR fuels were tested in pulsed solvent extraction columns. Tests were performed to study the effects of solvent degradation and solids in the feed and decontamination performance using tracer Zr-95. Equipment recommendations for each process step are made. The Acid-Thorex process is expected to provide relatively trouble-free operation in commercial reprocessing of HTGR fuel. (auth)

This report describes the design, fabrication, and calibration which have been completed for the modified specular photometer. The basic instrument is designed to examine the reflection or transmission of solar materials by measuring the amount of radiation which is reflected or transmitted by the material into a given acceptance aperture. (WDM)