A self-consistent design is described for a large tandem mirror experiment (MFTF-B) proposed to be constructed at the Lawrence Livermore Laboratory. Neutral-beam injected yin-yang mirror cells at each end of a 40 meter long central cell, provide MHD stability for the configuration, as in the TMX experiment. The largest potential well confining center-cell ions is generated by ECRH in auxiliary mirror cells (A-cells) added beyond the outer yin-yang mirrors. The required ECRH power (less than or equal to 1 MW) is minimized by use of thermal barriers installed at the local midplanes of each A-cell. In addition, the trapping of cold ions (n cold approx. n hot) in the local potential dips at the A-cell midplanes stabilize loss cone microstabilities. The impact of constraints imposed by neoclassical radial transport (resonant drifts), MHD stability (ballooning modes), and microstability (ion two-stream and loss cone modes) on the overall design will be assessed for the benefit of improving designs in future tandem mirror devices.

In a core schema that attempted to faithfully represent the inter-connectedness of the real world, each class role would need to be made explicit, naming its respectively associated classes and mappings. From each role a characteristic family of derived views can be inferred. In practice, this program need not be fully carried out as there are always connections in the real world which we choose not to model. But it is interesting to imagine an information system that behaved as if all (or at least all obvious) possible views had been automatically defined. It appears that humans have a system for doing some such automatic schema transformation in our natural semantic model of the world. As we constantly shift perspectives we seem always to be able to readily call up whatever role is appropriate for any given object in (mental) view. The work described falls in an area that is just on the edge of currently developing DB technologies. It is motivated by a desire to achieve systems that are more natural, more intelligent, and which better complement and support our own intellectual activity in the management and modelling of complex environments. There are, of course, many issues involved here …

A discussion is presented of issues of current importance in the theory and phenomenology of massive lepton pair production in hadronic interactions. The relevance of higher-twist inverse-power terms for all constituent scattering processes is emphasized. 7 figures.

Several major conceptual design studies of solar central receiver systems and components have been completed in the last year. The results of these studies are used to compare the projected cost of electric power generation using central receiver systems with that of more conventional power generation. The cost estimate for a molten salt central receiver system is given. Levelized busbar energy cost is shown as a function of annual capacity factor indicating the fraction of the cost due to each of the subsystems. The estimated levelized busbar energy cost for a central receiver (70 to 90 mills per kilowatt hour) is compared with the levelized busbar energy cost for a new coal fired Rankine cycle plant. Sensitivities to the initial cost of coal and the delta fuel escalation are shown. (WHK)

A gaseous sampling system was developed to differentially collect all major volatile forms of tritium and carbon-14 according to chemical class. These chemical forms include: tritiated forms of water, hydrogen and organics; as well as /sup 14/C-containing carbon monoxide, carbon dioxide and organics. Sampling campaigns involving the use of this differential /sup 3/H and /sup 14/C collection system have been successfully conducted at a high level liquid waste solidification plant, at a spent fuel storage facility and in the vicinity of power reactors.

Improved specific loading capacity for sodium fire aerosols was the objective of a sand and gravel test series. The aerosol capacity and related differential pressure of eight aggregate filters is presented. A maximum specific aerosol capacity, for dry aerosol, of 2.4 kg (Na) m/sup -2/ was obtained. This filter was loaded to a final differential pressure of 2.6 kPa. The average superficial face velocity was 0.5 cm/s and the average efficiency was 99.8%. The test results indicate that filter capacity increases with aerosol moisture content and with decreasing superficial velocity.

A novel air cleaning concept is being developed for potential use in venting reactor containment buildings. The two-stage system employs a pre-scrubber (a submerged gravel scrubber) and a fibrous scrubber to obtain high removal efficiencies for particulate contaminants. The submerged gravel scrubber is unique in that water flow is induced by the gas flow, eliminating the need for an active liquid pump. In addition, design gas velocities through the gravel bed are 10 to 20 times higher than for a conventional sand bed filter. A series of development tests have been performed on an engineering scale model with a gravel bed area of 0.07 m/sup 2/. Hydraulic tests indicate that the scrubber can be designed to operate at a superficial gas velocity of 0.50 m/s. Aerosol tests were performed with a variety of sodium fire aerosols. The aerosol mass removal efficiency for the pre-scrubber was 99.8% and the efficiency for the system exceeded 99.99%. The test results show that the aerosol removal efficiency is not a strong function of the gas velocity. Scale-up tests were made to evaluate gas distribution on a larger bed. The results demonstrated that the self-cleaning gravel bed can be scaled-up to the sizes required for …

A fluid-structure-interaction algorithm has been developed and incorporated into the two-dimensional code PELE-IC. This code combines an Eulerian incompressible fluid algorithm with a Lagrangian finite element shell algorithm and incorporates the treatment of complex free surfaces. The fluid structure and coupling algorithms have been verified by the calculation of solved problems from the literature and from air and steam blowdown experiments. The code has been used to calculate loads and structural response from air blowdown and the oscillatory condensation of steam bubbles in water suppression pools typical of boiling water reactors. The techniques developed have been extended to three dimensions and implemented in the computer code PELE-3D.

A Secure Automated Fuel Fabrication Line is being developed to reduce personnel exposure and to improve safeguards. Fertile and fissile fuel powders are blended in the line for making fuel pellets. A pressurized hopper was developed for use not only as a blender, but also as a storage and feeding device. It works with or without injection tubes to produce a well-blended powder with reduced agglomerate population. Results of blending experiments using dry Kaolin clay and Tempra pigment are given. (DLC)

The HTGR Risk Assessment Study has been extended to include major fires as initiating events. The major aspects of this study have included the development of methodology, the collection and interpretation of fire experience data and the application of these methods and data to an HTGR plant. Qualitative and quantitative methods were derived to screen a nuclear plant layout and identify important fire locations. A fire propagation model was used in conjunction with experience data and detailed fault tree analyses to estimate common cause failure probabilities associated with a spectrum of potential fires. It was determined that fires make a significant contribution to the HTGR risk assessment only at accident frequency levels below 10/sup -7//reactor-year.

Recent reports have demonstrated the possibility of employing photoactive, biological membrane components in photoelectrochemical cells. Present studies in our laboratories have led to the attachment of a much simpler biological complex, the bacterial photosynthetic reaction center isolated from Rhodopseudomonas sphaeroides, directly onto a SnO/sub 2/ semiconductor electrode. Light-induced photovoltages (70mV) and photocurrents (0.5 ..mu..A/cm/sup 2/) not attributable to Dember effects have been observed in photoelectrochemical cells employing reaction-center-coated, SnO/sub 2/ working electrodes. Such reaction-center electrodes may serve as model systems for future organic photovoltaic devices.

Current US energy policy includes many programs directed toward the restructuring of the energy system so as to decrease US dependence on foreign supplies and to increase our reliance on plentiful and environmentally benign energy forms. However, recent events have led to renewed concern over the direction of current energy policy. This study describes three possible energy strategies and analyzes each in terms of its economic, environmental, and national security benefits and costs. Each strategy is represented by a specific policy. The first strategy is to initiate no additional programs or policies beyond those currently in effect or announced. The second is to direct policy toward reducing the growth in energy demand, i.e., energy conservation. The third is to promote increased supply through accelerated development of synthetic and unconventional fuels. The analysis focuses on the evaluation and comparison of these strategy alternatives with respect to their energy, economic, and environmental consequences. The analysis indicates that conservation can substantially reduce import dependence and slow the growth of energy demand, with only a small macroeconomic cost and with substantial environmental benefits; the synfuels policy reduces imports by a smaller amount, does not reduce the growth in energy demand, and involves substantial environmental …

There is a growing interest in defining numerical safety goals for nuclear power plants as exemplified by an ACRS recommendation. This paper proposes a lower frequency limit of approximately 10/sup -4//reactor-year for design basis events. Below this frequency, down, to a small frequency such as 10/sup -5//reactor-year, safety margin can be provided by, say, site emergency plans. Accident sequences below 10/sup -5/ should not impact public safety, but it is prudent that safety research programs examine sequences with significant consequences. Once tentatively agreed upon, quantitative safety goals together with associated implementation tools would be factored into regulatory and design processes.

Bare fused silica surfaces were prepared by subjecting the mechanically polished surface to a rastered cw CO/sub 2/ laser beam. Analysis shows that this processing causes: (a) removal of a uniform layer of fused silica; and (b) a probable re-fusing or healing of existing subsurface fractures. The fused silica removal rate is found to be a function of the laser intensity and scan rate. These surfaces are seen to have very low scatter and to be very smooth. In addition, they have exhibited entrance surface damage thresholds at 1.06 ..mu..m, and 1 nsec, which are substantially above those seen on the mechanically polished surface. When damage does occur, it tends to be at a few isolated points rather than the general uniform damage seen on the mechanicaly polished part. In addition to the damage results, we will discuss an observational technique used for viewing these surfaces which employs dark-field illumination.

Cavity (void) formation and swelling in non-fissile materials during neutron irradiation and charged particle bombardments are reviewed. Helium is the most important inert gas and is primarily active as a cavity nucleant. It also enhances formation of dislocation structure. Preimplantation of helium overstimulates cavity nucleation and gives a different temperature response of swelling than when helium is coimplanted during the damage process. Helium affects, and is affected by, radiation-induced phase instability. Many of these effects are explainable in terms of cavity nucleation on submicroscopic critical size gas bubbles, and on the influence of the neutral sink strength of such bubbles. Titanium and zirconium resist cavity formation when vacancy loops are present.

This workshop attempted to evaluate the status of the current experimental and theoretical understanding of hot electron ring properties. The dominant physical processes that influence ring formation, scaling, and their optimal behavior are also studied. Separate abstracts were prepared for each of the 27 included papers. (MOW)

Yang-Mills theories admitting a charge conjugation, C, which reflects the representation of left-handed fermions f/sub L/ onto themselves, are reviewed with particular attention to flavor chiral theories, where f/sub L/ is non-self-conjugate. Simple cases of the fermion mass matrices in SO/sub 10/ and E/sub 6/ are studied, and it is observed that the weak isospin (I/sup w/)-conserving part of the mass can be classified into its C-conserving and C-violating pieces. If the left-handed fermions are assigned to families of 16's of SO/sub 10/ or 27's of E/sub 6/, then the hypothesis that the I/sup w/ invariant mass violates C maximally, with the C-conserving part put to zero, gives a simple explanation of the low-mass 5-bar + 10 bar structure of the families.

Initial experimental results from the Tandem Mirror Experiment (TMX) are presented. Axial profiles of the plasma density and potential necessary for electrostatically enhanced confinement of the central-cell ions have been generated and sustained for the duration of neutral-beam injection. The resulting central-cell ion confinement against axial loss is improved by a factor as large as 9 above that given by magnetic confinement alone. The plasma exhibits gross magnetohydrodynamic stability and microstability. Under some conditions, a residual level of ion cyclotron fluctuations in the end cells heats the central-cell ions and degrades their confinement.

Using a pilot-sized brine handling system at the Salton Sea Geothermal Field, a series of field tests have been conducted in which various chemical compounds were examined as possible scale control agents. Results of these tests are mentioned with reference to publications on them. (MHR)

Superconducting magnets for fusion energy reactors require massive monolithic stainless steel weldments which must operate at extremely low temperatures under stresses approaching 100 ksi (700 MPa). A three-year study was conducted to determine the feasibility of producing heavy-section welds having usable levels of strength and toughness at 4.2/sup 0/K for fabrication of these structures in Type 304LN plate. Seven welding processes were evaluated. Test weldments in full-thickness plate were made under severe restraint to simulate that of actual structures. Type 316L filler metal was used for most welds. Welds deposited under some conditions and which solidify as primary austenite have exhibited intergranular embrittlement at 4.2/sup 0/K. This is believed to be associated with grain boundary metal carbides or carbonitrides precipitated during reheating of already deposited beads by subsequent passes. Weld deposits which solidify as primary delta ferrite appear immune. Through use of fully austenitic filler metals of low nitrogen content under controlled shielded metal arc welding conditions, and through use of filler metals solidifying as primary delta ferrite where only minimum residuals remain to room temperature, welds of Type 316L composition have been made with 4.2K yield strength matching that of Type 304LN plate and acceptable levels of soundness, ductility …

Currently two simple theories are heavily used in laser-fusion research: the Thomas-Fermi-Dirac statistical model, and an atomic ionization model based on screened hydrogen like energy levels. Recent improvements in these theories are summarized. We show representation calculations of thermodynamic properties, ionization, x-ray emission rates and fast-ion stopping powers, and give a brief sketch of the major unresolved scientific questions.

Two blanket types are being studied: a lithium-sodium pool boiler and a lithium-oxide- or lithium-sodium pool boiler and a lithium-oxide- or aluminate-microsphere moving bed. For each, a wide variety of current technology was considered in handling the tritium. Here, we show the pool boiler with the sulfur-iodine thermochemical cycle first developed and now being piloted by the General Atomic Company. The tritium (T/sub 2/) will be generated in the lithium-sodium mixture where the concentration is approx. 10 ppM and held constant by a scavenging system consisting mainly of permeators. An intermediate sodium loop carries the blanket heat to the thermochemical cycle, and the T/sub 2/ in this loop is held to 1 ppM by a similar scavenging system. With this design, we have maintained blanket inventory at 1 kg of tritium, kept thermochemical cycle losses to 5 Ci/d and environmental loss to 10 Ci/d, and held total plant risk inventory at 7 kg tritium.

Experimental results are presented of the production of Field-Reversed Plasma with a high energy coaxial plasma gun. The gun is magnetized with solenoids inside the center electrode and outside the outer electrode so that plasma emerging from the gun entrains the radial fringer field at the muzzle. The plasma flow extends field lines propagating a high electrical conductivity, the flux inside the center electrode should be preserved. However, for low flux, the trapped flux exceeds by 2 or more the initial flux, possibly because of helical deformation of the current channel extending from the center electrode.

Although users of radiation desire measurement traceability for a number of reasons, including legal, regulatory, contractual, and quality assurance requirements, there exists no real definition of the term in the technical literature. Definitions are proposed for both traceability and traceability to the National Bureau of Standards. The hierarchy of radiation standards is discussed and allowable uncertainties are given for each level. Areas of need with respect to radiation standards are identified, and a system of secondary radiation calibration laboratories is proposed as a means of providing quality calibrations and traceability on a routine basis.