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.

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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.

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 improved annular centrifugal contactor has been developed for solvent extraction reprocessing of spent nuclear reactor fuel. The design is an extension of a contactor developed several years ago at Argonne National Laboratory. Its distinguishing features are high throughput, high stage efficiency and the ability to handle a broad range of aqueous-to-organic phase flow ratios and density ratios. Direct coupling of the mixing and separating rotor to a motorized spindle simplifies the design and makes the contactor particularly suitable for remote maintenance. A unit that is critically safe by geometry is under test and a larger unit is being fabricated. Multi-stage miniature contactors operating on the annular mixing principle are being used for laboratory flow sheet studies. 8 figures.

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.

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

A technique is described for the noncontact testing of materials using laser deposition to generate a stress pulse and interferometry to record the transient surface displacement. The dilatational wave speed can be measured and, in the particular case of rod or plate specimens, sufficient information can be obtained to evaluate the two elastic constants of an isotropic material. Several applications illustrating the advantages of the approach are summarized.

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

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)

The Lawrence Livermore Laboratory undertook an investigation of the properties of ferrite materials to be used in a 5-MeV, 50-ns linear induction accelerator. The investigation, on a part-time basis, lasted about one year and had the cooperation and helpful suggestions of several manufacturers: TDK of Japan, Phillips of Holland, and Stackpole of the U.S.A. Ferrites have been widely used as tuning cavities for proton synchrotron accelerators at radio frequencies. In such an application, the ..mu..Qf factor is used in describing the figure of merit for ferrites where a high duty factor requires low loss ferrites. In a linear induction accelerator with an average reprate of 5-Hz, the ferrite losses are negligible and the concept of complex permeability in describing the losses will not be introduced, but a large signal ..delta..B/..delta..H will be used to describe their properties. The properties of interest in designing the accelerating cavity were (1) flux swing ..delta..B = B/sub r/ + B/sub m/ greater than 0.5T; (2) a residual flux density B/sub r/ greater than or = to 0.15T with a reset no greater than 2 Oer; (3) a relatively high incremental ..mu.. greater than 400 to keep the excitation current small in relation to the …

The response of the pressure-suspension containment system of Mark I boiling-water reactors to a loss-of-coolant accident (LOCA) is being studied. This response is a design basis for light-water nuclear reactors. Part of the study is being carried out on a /sup 1///sub 5/-scale experimental facility that models the pressure-suppression containment system of the Peach Bottom 2 nuclear power plant. The test series reported here focused on the initial or air-clearing phase of a hypothetical LOCA. Measured forces, measured pressures, and the hydrodynamic phenomena (observed with high-speed cameras) show a logical interrelationship.

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.

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.

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.

Nondestructive analyses of plutonium can be made by detecting and measuring the gamma rays emitted by a sample. Although qualitative and semiquantitative assays can be performed with relative ease, only recently have methods been developed, using computer analysis techniques, that provide quantitative results. This paper reviews some new techniques developed for measuring plutonium. The features of plutonium gamma-ray spectra are reviewed and some of the computer methods used for spectrum analysis are discussed. The discussion includes a description of a powerful computer method of unfolding complex peak multiplets that uses the standard linear least-squares techniques of data analysis. This computer method is based on the generation of response profiles for the isotopes composing a plutonium sample and requires a description of the peak positions, relative intensities, and line shapes. The principles that plutonium isotopic measurements are based on are also developed, followed by illustrations of the measurement procedures as applied to the quantitative analysis of plutonium liquid and solid samples.

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 …

In certain high-current applications the resistance of the aluminum conductors is an important design parameter. Such a case is the aluminum exploding-bridge used in some nuclear detonators. The resistance of the network must be accurately known so that the individual bridge will receive the proper firing current. Vapor-deposited, thick aluminum films (0.011 mm) are often used to produce the necessary circuitry. These films are suitably masked and etched to make the conductors. Conventional etching methods for aluminum or aluminum-0.1 wt percent copper do not yield conductors with a well-defined, reproducible cross section. This results in unacceptable variations in electrical resistance. For this application, we have developed a new etching solution that contains 25 to 50 vol percent polyphosphoric acid, 75 to 50 vol percent orthophosphoric acid, and 10 to 30 g/l ferric chloride. Etching may be done at 55 to 65/sup 0/C, but for precision etching the temperature should be controlled to +-1/sup 0/C. The solution is useful for dip etching of aluminum circuits. The paper describes some limited production experience with this etch.

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.

To view and align Shiva laser targets, two new telemicroscopic instruments integral with TV camera and HeNe laser illuminator have been designed. The common requirement of both instruments is the capability of imaging two objects of different sizes on a TV screen: the large surrogate target (5 mm diameter) and the laser fusion target (0.250 mm diameter) with the same resolution (better than 7 ..mu..m). Both instruments have an optical relay which images the targets on a fixed reference reticle; the object is to center each target on the reticle. One of the instruments reimages the reticle plane onto the TV dectector using a zoom arrangement. This instrument translates the TV camera-zoom assembly in three axes and is thereby capable of exploring an object-space volume of 1 cm/sup 3/. In the other instrument, the reticle plane is reimaged by a zoom lens and this enlarged image is relayed to the TV detector by a cluster of five lenses. Four lateral lenses image the periphery of the surrogate target and the reticle for coincidence. The central objective images the center of the reticle and the fusion target when it is centered.

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.