A study of a series of copper(I) compounds which contain a strongly absorbing chromophore (e.g., CuBr(PPh/sub 3/)-(2,2'-bipyridine)) for use as sensitizers in photochemical energy storage systems is described. The generally low sensitization efficiencies of these compounds preclude their use as sensitizers in a practical photochemical energy storage system. Nevertheless, some interesting mechanistic information has emerged from this study, the full details of which are being written for publication. Also, the related compound, Ru(bipy)/sub 2/(NBD)/sup +2/, which features a norbornadiene molecule coordinated directly to a strongly absorbing metal containing fragment was examined. The original rationale for studying this compound was the expectation that the absorption of visible light would result in the population of an electronically excited state in which the electron density of the NBD is considerably perturbed. Relaxation of this state could then occur by a pathway which leads to the rearranged product, quadricyclene. It was found, however, that the sensitization efficiency of this compound is quite low. A comprehensive study of the factors which affect the sensitization efficiencies of Ir(bipy)/sub 2/(bipy')OH/sub 2//sup +3/ is unerway. In order to elucidate the mechanism(s) by which organic sensitizers affect the conversion of norbornadiene to quadricyclene, a study to measure the actual …

As part of the Jet Propulsion Laboratory's Low-Cost Solar Array Project, test methods have been evaluated and procedures developed for testing photovoltaic flat-plate solar cell modules for resistance to impact by hailstones. Testing has included the use of simulated hailstones (frozen ice spheres projected at terminal velocity), steel balls, and other projectile types applied with three loading methods: pneumatic gun, gravity drop, and static loading. Results are presented that compare the advantages and disadvantages of the three test methods. Dropped-steel-ball tests are shown to exhibit little correlation with high-velocity ice-ball tests, whereas statically-loaded steel balls show a somewhat better correlation with ice-ball tests. Results are also presented on the hail impact strength of 16 flat-plate photovoltaic modules. The module designs tested have been shown to be capable of withstanding as large as 1-1/2-inch diameter and not capable of withstanding as small as 1/2-inch diameter simulated hail. The top surface material of the modules has a dominant influence on the hail impact resistance of the modules. In order of increasing impact strength for a given thickness, the top surface materials encountered in the modules tester were: clear silicone rubber, annealed glass, tempered glass, and acrylic sheet. The critical failure mechanism of …

Separate abstracts were prepared for each of the three included sections. (MOW)

Semiscale gravity feed reflood and FLECHT-SET tests have been reviewed to determine phenomena which may be important during LOFT reflood. FLOOD4 and RELAP4/MOD6 predictions for Semiscale and FLECHT-SET tests were compared to experimental data. Based on these comparisons, uncertainties were estimated for the LOFT reflood predictions; these uncertainties were then utilized to bound the extent of cladding oxidation expected for the LOFT L2-3 and L2-4 tests.

Objectives, rationale, and method of a one-year experiment using a residential photovoltaic/thermal power system are presented. Data will be both archived and processed to investigate: (1) series heat pump system performance, and (2) electric utility impacts. A parallel heat pump system will be investigated in a subsequent experiment.

The prinicpal effort during this contract period was directed toward preparing for on-line radiochemical experiments at LAMPF directed toward studying rare processes such as (..pi../sup -/, ..pi../sup +/), (n, ..delta../sup + +/) and (..mu../sup -/, e/sup +/) in /sup 88/Sr. Chemical scavenging techniques to remove interfering products were shown to be effective without significantly affecting the sensitivity of the detection system. Sensitivities of less than 0.1 ..mu..b for the first two processes appear achievable. Detailed statistical analysis of last years' experiments is leading to new limits, about an order of magnitude lower than already reported, on the formation of polyneutrons, reinforcing the conclusion that such species are not particle stable. 100/sup -/GeV ..pi../sup -/ studies of copper spallation are revealing no dramatic differences between spallation with pions and that with protons. Essentially, this report consists of a collection of abstract-like summaries.

Transient processes in radiative transfer have recently become of interest in the modeling of astrophysical phenomena, particularly with regard to the brightness of novae, supernovae, and perhaps even galactic clouds adjacent to quasars. Analytic solutions to a particular class of Marshak wave problems are presented with and without the Marshak (Milne) boundary condition. The choice of boundary condition can have a decisive effect on the coupling of radiative energy to the material energy in the vicinity of a material boundary. The analytic solution obtained can be useful as a tool for calibrating numerical calculation techniques.

The prototype surface examination station for the Fuels and Materials Examination Facility (FMEF) will use closed circuit television (CCTV) for routine modes of operation along with a nuclear periscope for special examination needs. The CCTV and the nuclear periscope were evaluated against prescribed station requirements and compared in a side-by-side demonstration. A quantitative evaluation of their outputs showed that both systems were capable of meeting surface anomaly detection requirements. The CCTV system was superior in its ability to collect, suppress and present data into a more useful form for the experimenters.

The objective for the past quarter included reversing the decline in productivity from the methane fermenters, confirming methane and yeast production from acetate, and making trial runs on kraft mill and semichemical mill effluents. Although methane production remained low (20 cc/hr) addition of 2% methanol doubled production. Progress has been made on identifying possible viruses that might be preventing higher methane production. Confirmation that acetate can be used as a substrate for methane production has been obtained. An initial test on the Decker filtrate from a kraft mill gave 20 cc/hr methane production.

Reconstructing past climatic variations can lead to a better understanding of possible future precipitation and groundwater recharge patterns. Work so far has led to several new insights into past climate variability and will provide input into the hydrologic modeling effort in progress for the Waste Management Program. Short-term reconstructions (0 to 350 y) suggest that the basin and range of the southwestern United States have the driest, least variable precipitation record. The Pacific Northwest shows higher variability and several trends lasting for more then 25 y. The Southern High Plains have even more variability, but the upper Midwest and Southwest vary most and have the highest precipitation amounts. Pollen and lake level data from the literature suggest that the Southwest was wetter during at least part of the last glacial maximum than it is today.

Progress in the development of LMFBR and GCFR breeding blanket design parameters is reported under the following headings: interface self-shielding and advanced blanket investigations.

Some criteria for identifying dense plasmas are given. The theoretical analysis gives the following: general characteristics of dense plasmas, statistical model for compressed atoms, and ionization equilibrium in dense plasmas. (MOW)

This report is a summary of the SPSA Annual Technical Report. It covers Small Power Systems Applications activities for FY 1978. Studies were conducted to address current small power system technology as applied to power plants up to 10 MWe in size. Markets for small power systems were characterized and cost goals were established for the project. Candidate power plant system design concepts were selected for evaluation and preliminary performance and cost assessments were made. Economic studies were conducted at JPL and under contract to Burns and McDonnell. Breakeven capital costs were determined for leading contenders among the candidate systems. An applications study was made of the potential use of small power systems in providing part of the demand for pumping power by the extensive aqueduct system of California, estimated to be 1000 MWe by 1985. Criteria and methodologies were developed for application to the ranking of candidate power plant system design concepts. Experimental power plants concepts of 1 MWe rating were studied by three contractors as a Phase I effort leading toward the definition of a power plant configuration for subsequent detail design, construction, testing, and evaluation as Engineering Experiment No. 1 (EE No. 1). Site selection criteria and …

An intense absorption band of /sup 3/MBH/sup 2 +/ at 700nm was characterized in several media and its pK/sub A/ was measured to be 7.17 +- .1 in water. Flash photolysis show that semiethylene blue, MBH/sup +/, formed by quenching /sup 3/MBH/sup 2 +/ with Fe/sub II/(H/sub 2/O)/sub 6//sup 2 +/, decays by disproportionation at a diffusion-controlled rate. Rates of decay of the photostationary state of solutions of MB/sup +/ and Fe/sup II/(H/sub 2/O)/sub 6//sup 2 +/ in acidic media were measured using crossed beams to yield specific rates of oxidation of leucomethylene blue (MBH/sub 3//sup 2 +/) by MB/sup +/ (synproportionation) and by Fe(III). Laser flash-photolysis shows that quenching of MB/sup +/(S/sub 1/) by Fe(H/sub 2/O)/sub 6//sup 2 +/ can result in electron transfer to give MBH/sup +/. Profound differences between processes initiated by quenching triplet methylene blue with Fe(H/sub 2/O)/sub 6//sup 2 +/ and with stable coordination complexes of Fe(II) were found. Quenchers included (Fe/sup II/(CN)/sub 6/)/sup 4 -/, (Fe/sup II/(CN)/sub 4/(bpy)/sub 2/)/sup 2 -/, (Fe/sup II/(CN)/sub 2/(bpy))/sup 0/, and (Fe/sup II/(bpy)/sub 3/)/sup 2 +/. Measurements were made in aqueous and aqueous-alcoholic solutions at pH 2, 4.4, and 8.2. Quenching of /sup 3/MBH/sup 2 +/ or /sup 3/MB/sup …

In Furnace No. 1 during this quarter, experiments were conducted in which the total argon purge rate in this furnace was decreased. A number of extremely significant changes in the crystallographic structure and electronic quality of the ribbons were observed in these experiments. Ribbon segments were grown in which the equilibrium defect structure was no longer present and the electrical properties improved to the extent that cells of 50 cm/sup 2/ area having AM1 efficiencies over 11% could be prepared. In Furnace No. 3A, the final five-ribbon demonstration run was performed. The furnace performed nearly flawlessly over the 15 hour run during which approx. 30 meters of 5 cm wide ribbon were grown at a rate of approx. 3.3 cm/min from each of the five cartridges. Initial evaluation of a small lot of 45 cm/sup 2/ solar cells of approx. 9% (AM1) efficiency. Subsequent to this final multiple demonstration run, the furnace was converted to be operated with three 10 cm width cartridges, plus a melt replenishment unit. This conversion is now complete, and the first growth runs using one cartridge and the melt replenisher have produced approx. 4 meters of 10 cm wide ribbon at a growth rate of …

The status and program plans for the DOE program to design and develop a long-life, safe Brayton isotope power system for space power are described. (WHK)

The magnetic shields of the Mirror Fusion Test Facility neutral beam sources must keep the inner magnetic field below 0.15 mT inside an unsymmetrical ambient magnetic field of 0.05 to 1.5 T. Numerical computations and 1/10th-scale experiments were used to arrive at a three-layer shield design consisting of two thin nickel-iron alloy shells inside a thick mild steel shell. A 1/10th-scale prototype test confirmed the final design.

This report describes studies pertaining to long-term risks from the disposal of high-level nuclear waste in deep mined cavities. The results presented supplement peviously reported work. Previously studied scenarios are examined in greater depth, and the analysis is extended to deal with alternative fuel cycles.

In growth station JPL No. 1 the work during this quarter centered around trying to evaluate any influences on ribbon quality which might be caused by various materials of construction which are used in the growth furnace. At the present level of ribbon quality, which has produced 8.5% to 9.5% efficient solar cells, no particular influence of any furnace part was detected. The experiments rather led to the suspicion that the general environment and the somewhat unoptimized materials handling procedures might be responsible for the current variations in ribbon quality and that, therefore, continuous work with this furnace under rather more stringent environmental conditions and operating procedures could perhaps improve materials quality to some extent. The work on Machine 3A (the multiple furnace) was continued with two multiple growth runs being performed. In these runs, the melt replenishment system performed poorly and extensive modifications to it have been designed to make reliable melt feeding for five ribbon growth possible. Although in the first quality assessment runs ever performed with the melt replenishment system diffusion lengths nearly as great as those found in non-melt replenished runs were found, we have not yet apparently identified all the factors affecting SiC density in …

Processes which can lead to mobilization of brine adjacent to spent fuel or nuclear waste canisters and some of the thermomechanical consequences have been investigated. Velocities as high as 4 x 10/sup -7/ m s/sup -1/ (13 m y/sup -1/) are calculated at the salt/canister boundary. As much as 40 liters of pure NaCl brine could accumulate around each canister during a 10-year storage period. Accumulations of bittern brines would probably be less, in the range of 2 to 5 liters. With 0.5% water, NaCl brine accumulation over a 10-year storage cycle around a spent fuel canister producing 0.6 kW of heat is expected to be less than 1 liter for centimeter-size inclusions and less than 0.5 liter for millimeter-size inclusions. For bittern brines, about 25 years would be required to accumulate 0.4 liter. The most serious mechanical consequence of brine migration would be the increased mobility of the waste canister due to pressure solution. In pressure solution enhanced deformation, the existence of a thin film of fluid either between grains or between media (such as between a canister and the salt) provides a pathway by which the salt can be redistributed leading to a marked increase in strain rates …

This program was initiated in September 1976, with the objective and scope of determining the relationships between the shale characteristics, hydrocarbon gas contents, and well location, and thereby provide a sound basis for (1) assessing the productive capacity of the Eastern Devonian Gas Shale deposits, and (2) guiding research, development and demonstration projects to enhance the recovery of natural gas from the shale deposits. Included in the scope of the program are a number of elemental tasks as a part of the Resource Inventory and Shale Characterization subprojects of DOE's Eastern Gas Shales Project designed to provide large quantities of support data for current and possibly future needs of the Project.

Progress in LMFBR safety studies is briefly summarized.

This review covers the various approaches that have utilized the reversed-field concept. Its possible use in a working reactor is discussed. (MOW)

A Parabolic Dish-Electric Transport concept for dispersed solar thermal generation is considered. In this concept the power generated by 15 kWe Solar Generation Units is electrically collected in a large plant. Various approaches are possible for the conversion of mechanical shaft output of the heat engines to electricity. This study focuses on the Application of Field Modulated Generation System (FMGS) for that purpose. Initially the state-of-the-art of FMGS is presented, and the application of FMGS to dispersed solar thermal electric generation is investigated. This is followed by the definition of the control and monitoring requirements for solar generation system. Then comparison is made between FMGS approach and other options. Finally, the technology developmental needs are identified.