Core restraint systems in LMFBRs maintain control of core mechanics and configuration behavior. Core restraint design is complex due to the close spacing between adjacent components, flux and temperature gradients, and irradiation-induced material property effects. Since the core assemblies interact with each other and transmit loads directly to the core restraint structural members, the core assemblies themselves are an integral part of the core restraint system. This paper presents an assessment of several advanced core restraint system and core assembly concepts relative to the expected performance of currently accepted designs. A recommended order for the development of the advanced concepts is also presented.

Separate abstracts have been entered into the data base for each included paper. (MOW)

A series of alloys have been developed as possible replacements for some austenitic stainless steels. These alloys utilized a Mn substitution for Ni and a reduced Cr concentration from the 18% ordinarily found in the AISI 300 series stainless steels to a concentration of 13%. The base system studied was an alloy containing Fe-16%Mn-13%Cr while other elements added included small additions of N, Si and Mo. A range of microstructures was produced from the alloying additions. The base composition had a triplex (fcc, hcp, bcc) structure while the most highly modified compositions were fully austenitic. Mechanical testing included tensile testing and Charpy V-notch testing conducted at various temperatures between -196/sup 0/C to 23/sup 0/C. Excellent combinations of strength and ductility were obtained (40--65 ksi yield strength, 100--125 ksi ultimate strength, 45--75% elongation and 60--80% reduction of area) at room temperature. Upper shelf energies in Charpy V-notch testing were as high as 185 ft-lbs with a ductile-brittle transition temperature (DBTT) of -160/sup 0/C. Analysis of fracture surfaces determined that alloys without interstitials had no transition in the mode of failure between room temperature and liquid nitrogen temperature. Results of an ASTM sensitization corrosion test, where the experimental alloys were compared to …

The record for the first of the public briefings in the Consumer Information Series scheduled by the Department of Energy is presented. The series presents, for public information and discussion, those DOE policies and programs of specific interest to consumers and public interest groups. In the first meeting DOE officials responded to questions from the public on the DOE role in nuclear policies and programs.

Laboratory tests were conducted on some potential MHD elecrode materials to evaluate their electrochemical reactions. Electrode materials 0.25Fe/sub 3/O/sub 4/ 0.75MgAl/sub 3/O/sub 4/ (FMAS), La/sub 0/ /sub 95/Mg/sub 0/ /sub 03/CrO/sub 3/ (LMC), and 0.10Tb/sub 4/O/sub 7/ 0.90HfO/sub 2/ (THF) were tested in both liquid ana vapor K/sub 2/CO/sub 2/ and K/sub 2/SO/sub 4/, as well as potassium seed. Tests have confirmed that electrochemical reactions are substantially accelerated in these materials when used as electrical conductors. Electrochemical effects are functions of electrolyte composition (especially Fe and K), temperature, and electric current density.

The status of energy-averaged cross sections of fast-reactor structural materials is outlined with emphasis on U.S. data programs in the neutron-energy range 1-10 MeV. Areas of outstanding accomplishment and significant uncertainty are noted with recommendations for future efforts. Attention is primarily given to the main constituents of stainless steel (e.g., Fe, Ni, and Cr) and, secondarily, to alternate structural materials (e.g., V, Ti, Nb, Mo, Zr). Generally, the mass regions of interest are A approximately 50 to 60 and A approximately 90 to 100. Neutron total and elastic-scattering cross sections are discussed with the implication on the non-elastic-cross sections. Cross sections governing discrete-inelastic-neutron-energy transfers are examined in detail. Cross sections for the reactions (n;p), (n;n',p), (n;..cap alpha..), (n;n',..cap alpha..) and (n;2n') are reviewed in the context of fast-reactor performance and/or diagnostics. The primary orientation of the discussion is experimental with some additional attention to the applications of theory, the problems of evaluation and the data sensitivity of representative fast-reactor systems.

Computerized graphics techniques available in the Department of Energy's national laboratories for use in the environmental aspects of energy such as land use planning (including siting), and regional studies, environmental impact assessment are discussed. Areas covered include: computer graphics; mapping/cartography; image processing; animation; computer movies; satellite graphics; surface representation; land use analysis; pattern recognition; demographics analysis; ecological analysis; and biomedical applications. Descriptions of each graphics system included should be sufficient for a potential user to determine its possible use to him. Further, information is available by writing or telephoning the indicated contact person.

Thermochemical cycles for the production of synthetic fuels would be especially suited for operation in conjunction with controlled thermonuclear fusion reactors because of the very high temperature energy which such reactors could supply. Furthermore, fusion energy when developed is considered to be an inexhaustable supply of energy. Several high-temperature two-step thermochemical cycles for the production of hydrogen are examined. A thermodynamic analysis of the Fe/sub 3/O/sub 4/--FeO, CrCl/sub 3/--CrCl/sub 2/, and UCl/sub 4/--UCl/sub 3/ pairs reveals the feasibility of the process. A more detailed process analysis is given for the Fe/sub 3/O/sub 4/--FeO system using steam as the heat transfer medium for decomposing the higher valent metal oxide for oxygen production, and hydrolysing the lower oxide for hydrogen production. The steam could be heated to high temperatures by refractory materials absorbing the 14-MeV neutrons in the blanket region of a fusion reactor. Process heat transfer and recovery could be accomplished by regenerative reactors. Proposed operating conditions, the energy balance and the efficiency of the water decomposition process are presented. With a fusion blanket temperature of 2500/sup 0/K, thermal efficiencies for hydrogen production of 74.4% may be obtained.

The authors define and discuss several approaches to establishing de minimis levels, with examples. In order to avoid creating still another constraint on waste facilities or controls, they suggest the term de minimis be applied only when based on environmental radioactivity, dose, or health effect. They further suggest that such usage implies case-by-case numerical evaluation for application to release rates or effluent concentrations.

Some possible characteristics of the new quark suggested by the discovery of T(9.4) are surveyed. An inverse scattering approach to the interquark potential is summarized. 52 references.

An analysis of nondestructive testing (NDT) methods currently being used to evaluate the integrity of Light Water Reactor (LWR) spent fuel shipping casks is presented. An assessment of anticipated NDT needs related to breeder reactor cask requirements is included. Specific R and D approaches to probable NDT problem areas such as the evaluation of austenitic stainless steel weldments are outlined.

A study of fluid mechanical effects on unburned hydrocarbon generation was made in a single compression expansion model automobile engine. Full optical access allowed the color Schlieren observations of various gas motion alongside the engine cylinder. Motion pictures of the gas motion and flame propagation were taken at a rate of seven thousand frames per second for the following cases: (1) intake stroke; (2) exhaust stroke; and (3) compression power stroke with combustion and blow-down with appropriate exhaust valve opening. Unburned fuel concentrations were measured by means of a gas chromatograph. The results show that turbulent motion of the mixture increases the amount of unburned fuel. It is implied that the rolled-up vortices play an important role on wall flame quenching processes in an engine.

The current national program comprises the following major activities: (1) preliminary design, systems studies, and cost estimates for a reference 'pilot-plant' driver [Beam energy = 1 MJ; Beam power on target = 100 TW; specific energy deposition {ge} 20 MJ/gm]; (2) consequent upon this reference design, definition of an intermediate Heavy Ion Demonstration Experiment (HIDE) to test the accelerator technology and to begin to probe the scaling behavior of the heavy-ion target behavior, current thinking suggests that the beam energy should be about 100 kJ, or roughly one-tenth that of the reference design, in present DOE plans, HIDE is assumed to be operating in FY1985 or FY1986. (3) Design of targets optimized for heavy-ion driver; relaxation of the high beam-power requirements would allow accelerator designs to produce lower kinetic energy for the ion and permit a longer final pulse duration, thus easing a difficult demand on present-day accelerator behavior; (4) development of a clear understanding of the design implications of the beam space-charge limits, both longitudinal and transverse, several of the accelerator system design parameters, e.g apertures, number of final beams, size of final focusing magnets, are sensitive to assumptions about the six-dimensional phase-space density and volume of the beam. …

A large volume water sampler using manganese dioxide impregnated cartridges for the in situ separation of plutonium in sea water and ground water was studied. Plutonium concentrations obtained by this technique are compared with a radiochemical coprecipitation method. Consistent results were obtained between the two methods for water samples from the Pacific Ocean and Enewetak lagoon. Different results were noted from samples collected in the Enewetak reef and ground water stations. Using this preconcentration technique and the coprecipitation method it was shown that the physical-chemical characteristics of Pu in Enewetak reef and ground water are different from the lagoon and open ocean.

On the basis of measured temperature distributions in electron beam welding cavities it is shown that the vapor pressure force dominates in the lower region and the surface tension in the upper region. The region where these two forces are approximately equal is unstable and the surface tension force causes inward flow of liquid metal which tends to form a projection. For a specific material this projection location was found to depend on cavity depth. By postulating that the formation of liquid metal projections at this location results in cavity instabilities, a physical model for predicting when spiking would occur was purposed. A procedure then developed for determining the spiking tendency for a specified material and set of weld parameters is described.

Asynchronous Chinese hamster cells were irradiated with 10 Jm/sup -2/ uv radiation and 0.25 to 4 hours later pulse-labeled with (/sup 3/H)thymidine. Cells synchronized by shaking off mitotic and G/sub 1/ cells were irradiated in either the G/sub 1/-phase or S-phase of the cell cycle and pulse-labeled with (/sup 3/H)thymidine in the S-phase. After a 12 to 14 hour chase in unlabeled medium, the DNA was extracted, incubated with Micrococcus luteus uv-endonuclease and sedimented in alkaline sucrose. The number of endonuclease sensitive sites decreased as the time between uv irradiation and pulse-labeling of daughter DNA increased. Further, there were significantly less endonuclease sensitive sites in the daughter DNA from cells irradiated in the G/sub 1/-phase than in the S-phase. These data indicate that very few, if any, dimers are transferred from parental DNA to daughter DNA and that the dimers detected in daughter DNA may be due to the irradiation of replicating daughter DNA before labeling.

Separate abstracts were prepared for each of the 50 included papers. (MOW)

The Hanford Purex Plant has demonstrated suitability for reprocessing irradiated thoria (ThO/sub 2/) target elements on a campaign basis. A 1965 process test and major production campaigns conducted in 1966 and 1970 recovered nitrate solution form products totaling approximately 565 tons of thorium and 820 kilograms of /sup 233/U. The overall recoveries for the 1970 campaign based on reactor input data were 94.9 percent for thorium and 95.2 percent for uranium. The primary function of the Hanford Purex Plant is reprocessing of irradiated uranium fuel elements to separate and purify uranium, plutonium and neptunium. Converting the plant to thoria reprocessing required major process development work and equipment modifications. The operation and performance of the Plant during the 1970 thoria reprocessing campaign is discussed in this report. The discussion includes background information on the process and equipment, problems encountered, and changes recommended for future campaigns.

Fast Flux Test Facility (FFTF) cold traps, including the Reactor Primary Cold Trap, the Reactor Secondary Cold Trap and the Closed Loop Cold Trap were fabricated and their thermal performances measured on sodium test systems. The cold traps all met reactor requirements after necessary economizer modifications. Mercury tests were performed to study the effect of woven wire packing on the flow of a liquid metal adjacent to a heated vertical wall as occurs in the cold trap crystallizer. The mesh was observed to alter the velocity distribution in the natural convection flow region. Cold trapping experiments have been done to determine the interaction of hydrogen and tritium isotopes during precipitation. It was determined that the hydrogen removal rate is of primary importance in tritium removal from sodium. Isotopic exchange plays a negligible role in cold trapping tritium. A one-dimensional computer model has been developed to predict hydride and oxide precipitation patterns. Experiments have been done using an essentially one-dimensional (long, thin) tube to compare results with the model.

This report contains the program and abstracts of papers presented at the Second American Physical Society Topical Conference on High Temperature Plasma Diagnostics, March 1-3, 1978, Santa Fe, New Mexico.

The goals of the United States Department of Energy sodium removal and decontamination programs are (1) to identify plant requirements and develop safe effective processes for sodium removal, both for experimental facilities and for reactor components, (2) to develop effective decontamination processes for removing deposited radioactivity, (3) to establish and put into use a set of workable criteria for requalification and return to service of components after sodium removal and decontamination, (4) to design, build and operate facilities in which to perform the sodium removal and decontamination operations. The paper gives a summary of progress toward each of these goals. Three basic processes for sodium removal have been investigated extensively: the use of water vapor in an inert carrier gas, the use of alcohol-type reagent, and evaporation. The process development work on the first two processes has been essentially completed. The evaporative process is still under development, but preliminary parameters have been established.

Coal-oil mixture (COM) combustion technology is regarded by the Department of energy as near term, and potentially applicable to existing utility and industrial steam generators, and for injection into blast furnaces. From work done previously, it has been established that COM can be existing boilers and blast furnaces. Therefore, the issues being addressed by the current DOE program are: (1) determination of best available technology to achieve environmentally-acceptable long-term reliable operation, and (2) determination of applications for which COM can be utilized economically. Some of the technological options have begun to be determined by projects already under way. However, many projects are still in the early stages of development.

A transport equation theory of electron backscattering and x ray production is derived and applied to energy dissipation of 30-KeV electrons for copper as a function of depth and to the energy distribution of backscattered electrons for copper, aluminum, and gold. These results are plotted and compared with experiment. Plots for variations of backscattering with atomic number and with angle of incidence, and polar plots of backscattering for 30-keV electrons at normal incidence are also presented. 10 references, seven figures. (JFP)

A MWPC camera for Nuclear Medicine imaging with positron emitting isotopes has been built. The two planar detectors are converter coupled MWPC with sensitive area 48 x 48 cm/sup 2/ placed 50 cm apart with clear space in between for the patient. The effective sensitivity of 5.8% for each detector with a spatial resolution of 7 mm FWHM on the image plane is achieved by use of honeycomb lead-on-plastic onverters. Present performance in imaging test objects and in clinical applications is described, using various computer 3D reconstruction algorithms. Developments in progress include the use of small diameter lead oxide glass tube converters; techniques to eliminate multiple scatter events and improve the point response function; and electronics to provide accidental event subtraction.