Two large aperture, 10 cell atmospheric-pressure isobutane Cherenkov counters were designed and constructed for a SLAC streamer chamber experiment. The rejection efficiencies for a 9 GeV/c ..pi../sup -/ were measured to be 99.838 +- .006% and 99.717 +- 008% for the two counters. The design details and performance characteristics are discussed.

The explanation of SN Type I by radioactive decay of /sup 56/Ni requires a relatively small value of the transparency function M/sub ej//v/sub 9//sup 2/ = 0.22 in units of M/sub solar/'s and 10/sup 9/ cm s/sup -1/ to explain the light curve. A minimum mass of /sup 56/Ni is required to explain the peak and near peak luminosity. Subsequent radioactive decay energy must escape in some other form than optical light in order to explain the rapid early and late time decay. Early ultraviolet and infrared radiation are excluded as sinks of energy by observations. PdV work is excluded by theory. The energy loss due to the escape of gamma rays and ..beta../sup +/'s with the above value of M/sub ej//v/sub 9//sup 2/ gives good agreement with the light curve after maximum, provided essentially all the trapped energy is converted to optical light. The peak of SN 1972e is explained with the above transparency value M/sub ej//v/sub 9//sup 2/ = 0.22 and mass of /sup 56/Ni of 0.25 M/sub solar/ or 0.4 M/sub solar/, and a distance of 3.2 Mpc or 4 Mpc, respectively. These values depend critically upon the prediscovery report of Austin (1972), and the assumption again …

Separate abstracts are prepared for twelve papers presented at the symposium. (MCW)

The friction, wear, and corrosion performance of several metallurgical coatings in 200 to 650/sup 0/C sodium are reviewed. Emphasis is placed on those coatings which have successfully passed the qualification tests necessary for acceptance in breeder reactor environments. Tests include friction, wear, corrosion, thermal cycling, self-welding, and irradiation exposure under as-prototypic-as-possible service conditions. Materials tested were coatings of various refractory metal carbides in metallic binders, nickel-base and cobalt-base alloys and intermetallic compounds such as the aluminides and borides. Coating processes evaluated included plasma spray, detonation gun, sputtering, spark-deposition, and solid-state diffusion.

Initial tandem mirror hybrid studies predict the ability to produce large amounts of fissile fuel (2 to 7 tons U233 per year from a 4000 MW plant) at a cost that adds less than 25% to the cost of power from a LWR.

Lasers for fusion experiments use thin-film dielectric coatings for reflecting, antireflecting and polarizing surface elements. Coatings are most important to the Nd:glass laser application. The most important requirements of these coatings are accuracy of the average value of reflectance and transmission, uniformity of amplitude and phase front of the reflected or transmitted light, and laser damage threshold. Damage resistance strongly affects the laser's design and performance. The success of advanced lasers for future experiments and for reactor applications requires significant developments in damage resistant coatings for ultraviolet laser radiation.

The U.S. Department of Energy, Division of Geothermal Energy and Division of Geothermal Resource Management, sponsored a Resource Assessment/Commercialization Planning meeting in Salt Lake City on January 21-24, 1980. The meeting included presentations by state planning and resource teams from all DOE regions. An estimated 130 people representing federal, state and local agencies, industry and private developers attended.

The progress and management of the Department of Energy's geothermal loan guarantee program are discussed. Recommendations for improving the program and matters for consideration by the Congress are included. (MHR)

The Shiva Laser at LLL requires many forms of diagnostics to measure and analyze fusion experiments. This manual describes the operation of a Micro-Processor controlled data acquisition system designed at LLL to measure Neutron Activation during fusion experiments on the Shiva Laser.

A computer simulation code has been developed and validated at the Lawrence Livermore National Laboratory (LLNL) to predict the performance of a railgun electromagnetic accelerator. The code, called MAGRAC (MAGnetic Railgun ACcelerator), models the performance of a railgun driven by a magnetic flux compression current generator (MFCG). The MAGRAC code employs a time-step solution of the nonlinear time-varying element railgun circuit to determine rail currents. From the rail currents, the projectile acceleration, velocity, and position is found. The MAGRAC code was validated through a series of eight railgun tests conducted jointly with the Los Alamos Scientific National Laboratory. This paper describes the formulation of the MAGRAC railgun model and compares the predicted current waveforms with those obtained from full-scale experiments.

We describe a typical 2D magnetohydrodynamic (MHD) calculation of rundown of plasma in a coaxial, magnetized gun and injection of the plasma and reconnection of the embedded magnetic fields to form a compact toroidal plasma.

The corrosion resistance of six different types of weighted metal coupons was evaluated at 29/sup 0/C (84/sup 0/F) in flowing water containing nitrite-borate-silicate corrosion inhibitors. The question for evaluation was whether it would be more advantageous: (1) to drain the treated cooling water from the centrifuge machine and to expose them to moisture-laden air over an assumed shop downtime and repair perid of 1 month; or (2) to let the treated cooling water remain stagnant in the machines during this downtime. The moisture-laden-air exposure was more detrimental.

It has been assumed that acid rain is predominantly a problem of long-range transport of pollutants from large fossil fuel combustion sources, namely coal-fired utilities. However, close examination of fuel use information and source emission characteristics in the Adirondacks, Florida, and California suggests that local oil burning and automotive sources may be major contributors to the occurrence of acid rain in these areas. This report describes the possible role of local combustion sources in the production of acid rain, discusses the implications of the findings, and their relevance to alternative control strategies for acid rain. Oil-fired boilers, especially the smaller commercial, industrial, and residential units, produce at least 3 to 10 times as much primary sulfate per unit of sulfur content as coal-fired units. Moreover, oil-fired units emit comparatively large quantities of catalytic compounds capable of rapidly converting still more sulfur oxide to sulfate in the atmosphere. Thus, in areas where large quantities of oil are burned, the direct impact from locally generated sulfates may equal or even exceed that produced by imported sulfates derived from distant coal-burning sources. Fuel consumption data show that large quantities of oil are being consumed in areas experiencing acid rain. Forty percent of the …

The incentives for separating and eliminating various elements from radioactive waste prior to final geologic disposal were investigated. Exposure pathways to humans were defined, and potential radiation doses to an individual living within the region of influence of the underground storage site were calculated. The assumed radionuclide source was 1/5 of the accumulated high-level waste from the US nuclear power economy through the year 2000. The repository containing the waste was assumed to be located in a reference salt site geology. The study required numerous assumptions concerning the transport of radioactivity from the geologic storage site to man. The assumptions used maximized the estimated potential radiation doses, particularly in the case of the intrusion water well scenario, where hydrologic flow field dispersion effects were ignored. Thus, incentives for removing elements from the waste tended to be maximized. Incentives were also maximized by assuming that elements removed from the waste could be eliminated from the earth without risk. The results of the study indicate that for reasonable disposal conditions, incentives for partitioning any elements from the waste in order to minimize the risk to humans are marginal at best.

The results of this study demonstrate that the Ir-promoted Ni/Al/sub 2/O/sub 3/ catalyst possesses several valuable and superior characteristics when used for catalytic methanation under typical industrial conditions. These properties include: higher activity by a factor of > 2 than that of the unpromoted Ni/Al/sub 2/O/sub 3/ catalyst; enhanced resistance to deactivation by hydrogen sulfide during exposure to contaminated feedstock, as manifested by the prolonged high methanation activity and extended service lifetime; and high resistance to carbon fouling.

Work on this project is focused on developing design and licensing information for the model facility. The subcontracts for soils and structural design and the security system design have been completed. The rack design subcontract is progressng satisfactorily. Design of facility modifications have been completed and draft reports are underway. Licensing documentation is approximately 65% complete and progressing at a satisfactory pace to meet scheduled projections.

The Spent Fuel Test-Climax (SFT-C) is a test of dry geologic storage of spent nuclear reactor fuel. The SFT-C is located at a depth of 420 m in the Climax granitic stock at the Nevada Test Site. Eleven canisters of spent commercial PWR fuel assemblies are to be stored for 3 to 5 years. Additional heat is supplied by electrical heaters, and more than 800 channels of technical information are being recorded. The measurements include rock temperature, rock displacement and stress, joint motion, and monitoring of the ventilation air volume, temperature, and dewpoint.

Oligomer mixtures of 800, 2200, and 4000 molecular weight polystyrene have been fractionated using silica and bonded phase columns under similar conditions of solvent gradient and flow rate. Using a hexane/tetrahydrofuran gradient, the silica and nitro phases were best in that they separated 41 and 43 oligomers, respectively. At the other extreme, a phenyl bonded phase column gave virtually no resolution using a water/THF gradient and a cyano bonded phase column, using the earlier hexane/tetrahydrofuran system, resolved only 10 oligomers. Amino and octadecyl bonded phase columns gave results intermediate between these two extremes. The strength of the solvent used to dissolve the sample was found to be of critical importance. Use of too good a sample solvent seriously degraded the attainable resolution. When number average and weight average molecular weights for an 800 molecular weight polystyrene sample were calculated from the oligomer distribution, the silica column gave values which were most consistent with those reported from other methods.

Commercial 2-1/4 Cr-1 Mo low strength steel specimens have been tested to measure their susceptibility to hydrogen embrittlement in an environment of H/sub 2/S at 50 psig. It was found that two factors, viz. (i) the plane stress zones on the crack front in compact tension specimens and (ii) incubation time effects, seriously confounded measurements on these steels when tested by conventional rising load experiments. Because of the incubation time effect, K/sub or/ (the stress intensity at which cracking starts in a rising load test) is a loading rate dependent variable and is usually significantly greater than the arrest stress intensity, K/sub arr/ in a bolt loaded test. K/sub arr/ must therefore be used as a measure of hydrogen resistance. The incubation time has been significantly reduced by cyclicly loading in the environment to initiate the crack and K/sub arr/ has been measured by holding the specimen in constant displacement immediately after crack initiation. The plane stress problem has been eliminated by deeply side grooving the compact tension (CT) specimens. As an example of the importance of these effects a 3T CT smooth sided specimen was compared with a side grooved 2T CT specimen of the same steel. Whereas the …

Commercial 2 1/4 Cr-1 Mo low strength steel specimens have been tested to measure their susceptibility to hydrogen embrittlement in an environment of H/sub 2/S at 50 psig. It was found that two factors, viz. (1) the plane stress zones on the crack front in compact tension specimens, and (2) incubation time effects, seriously confounded measurements on these steels when tested by conventional rising load experiments. Because of the incubation time effect, K/sub or/ (the stress intensity at which cracking starts in a rising load test) is a loading rate dependent variable and is usually significantly greater than the arrest stress intensity, K/sub arr/ in a bolt loaded test. K/sub arr/ must therefore be used as a measure of hydrogen resistance. The incubation time has been significantly reduced by cyclicly loading in the environment to initiate the crack and K/sub arr/ has been measured by holding the specimen in constant displacement immediately after crack initiation. The plane stress problem has been eliminated by deeply side grooving the compact tension (CT) specimens. As an example of the importance of these effects a 3T CT smooth sided specimen was compared with a side grooved 2T CT specimen of the same steel. Whereas …

The growth rate of plant cells can be defined in terms of five parameters: the hydraulic conductivity of the tissue (L'p), the rate of export from the cell to the wall of a wall loosening factor (dW/dt), the capacity of the wall to be loosened in response to the wall loosening factor (WLC), the osmotic potential of the cells and outside solution (..pi../sub c/ and ..pi../sub o/, respectively), and the yield threshold for wall expansion (Y). The study assesses each of these parameters under conditions where growth is being enhanced or inhibited, with the purpose of explaining at the cellular level just how growth is being controlled. (ACR)

A simple model is derived to calculate the hydrodynamic decay of laser-generated shock waves. Comparison with detailed hydrocode simulations shows good agreement between calculated time evolution of shock pressure, position, and instantaneous pressure profile. Reliability of the model decreases in regions of the target where superthermal-electron preheat effects become comparable to shock effects.