Efforts at the Jet Propulsion Laboratory toward the production of pure polycrystaline silicon are centered on the concept of silicon particle growth in a fluidized bed reactor (FBR) and a continuous flow pyrolyzer (CFP). The CFP possibly can provide the seed particles which will be grown to larger sizes in the FBR. In both the reactors polycrystalline silicon is obtaned from the pyrolysis of silane. A part of the JPL effort is to develop a model of silicon particle growth for the purpose of predicting particle growth rates and product particle size distributions in the FBR and the CFP. This repot describes the mathematical models of silicon particle growth in the FBR and the CFP.

The impacts described here for 1985 and 1990 are based on a national energy projection which assumes medium energy demand and fuel supply through 1990 but does not incorporate the policies of the National Energy Act (NEA). This scenario, referred to as the Projection Series C or the TRENDLONG MID-MID scenario, is one of six possible energy futures developed by the DOE Energy Information Administration for the Department's 1977 Annual Report to Congress. It was chosen as representative of the official DOE national energy projections when this project was initiated, prior to the passage of the National Energy Act. Since the RIIA program is part of an ongoing review of the regional impact of energy policies, the next phase will examine the National Energy Act (NEA) and initiatives suggested by the President's second National Energy Plan. However, since coal utilization increases under the NEA, in general, impacts identified in the TRENDLONG Series C Scenario should provide a framework for the discussion of impacts by NEA. The environmental impacts discussed in this volume are for Federal Region I (Maine, Vermont, New Hampshire, Massachusetts, Rhode Island, and Connecticut). However, there are nine companion volumes, one for each of the other Federal Regions.

Thermochemical equilibrium computations for the preparation of silicon (Si) by the reaction between sodium (Na), either liquid or vapor, with silicon tetrafluoride (SiF/sub 4/) and silicon tetrachloride (SiCl/sub 4/) are presented. Computations indicate that SiF/sub 4/ reacts with either liquid or gaseous Na to produce temperatures sufficiently high to form molten Si. Liquid Na reacts with SiF/sub 4/ to produce substantially higher Si yields than does the free combustion reaction with Na vapor; however, the Na vapor/SiF/sub 4/ reaction, if temperature-constrained at the Si melting point, produces an expected Si yield close to 100%. A stoichiometric mixture of liquid Na and SiCl/sub 4/ vapor reacts to produce liquid Si, gaseous sodium chloride (NaCl), and a small concentration of Si subhalides. Gaseous Na, however, reacts with SiCl/sub 4/ to form entirely gaseous reaction products and a high yield of Si (liquid) but subhalide concentrations are greater than when liquid Na is used. The reactions of a number of impurity elements in Na, during the course of the Na-Si halide reaction, have been described. Of those considered, only calcium (Ca), magnesium (Mg), phosphorus (P), and strontium (Sr) are expected to co-exist to any extent in Na vapor and none is expected to …

A computer-assisted thermochemical equilibrium analysis was conducted for the silicon transport reaction: Si(s) + SiF/sub 4/(g) = (intermediates) = Si(s) + SiF/sub 4/(g). The calculations indicated that a substantial transport rate should be possible at temperatures of 1700/sup 0/K and one atmosphere pressure. Computations were made to determine whether the elemental impurities present in metallurgical-grade silicon would transfer in this process. It was concluded that aluminum, chromium, copper, iron, manganese, molybdenum, nickel, vanadium, and zirconium would not transfer, but that boron, magnesium, phosphorus, and titanium would transfer.

This report is the first in a series and details the results accomplished under the following tasks: (1) evaluation of existing passive solar calculation methods, (2) BLAST/DOE-1 program interface and comparison with BR-202, and (3) development of analytic relationships between the thermal balance and weighting factor techniques. The various methods available for use in thermal load analysis are presented with detailed informaton on algorithms used in the thermal balance and weighting factor techniques. (MOW)

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 …

The structure and electrical activity of planar defects in EFG Silicon was investigated by optical, electron beam induced current (EBIC), and transmission electron microscopy (TEM). What appears to be twin boundaries by both optical microscopy + etching, and by EBIC are in reality systems of microtwins, some of which are only a few atomic lattice planes thick. The electrical activity of planar defects appears to be correlated with emission of dislocations especially at termination points. Impurity effects may also play a role. Twin boundaries per se appear not to be electricaly active.

The Fusion Materials Irradiation Test Facility (FMIT) is a high-energy, high-flux neutron source for fusion materials development. The FMIT linear accelerator will produce a 35 MeV beam of deuterons that generates high-energy neutrons by a nuclear stripping reaction with flowing liquid lithium targets. The targets will be located in two identical irradiation test cells, either of which will provide an irradiation volume of 10 cm/sup 3/ at a neutron flux of 10/sup 15/ n/cm/sup 2/-s and 500 cm/sup 3/ at a flux of 10/sup 14/ n/cm/sup 2/-s. FMIT has been authorized by the US Congress and will be constructed and operated by the Hanford Engineering Development Laboratory (HEDL) at Richland, Washington, in collaboration with the Los Alamos Scientific Laboratory (LASL) which is providing the accelerator design. The project is currently entering the detailed design phase, targeting for start of construction in early 1980 and operaion in 1983-84. Research and development programs are underway at both HEDL and LASL to resolve uncertainties in the lithium target and accelerator designs.

This program has the objective 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. The Y-1 well in Allegany County, New York was sampled in September 1978. 412 samples were collected from the Allegany County, New York well. Characterization data on Y-1 (EGSP New York No. 1), Allegany County, New York well is reported and discussed. Analysis of the hydrocarbon gases in Y-1 samples indicates that the longer chain hydrocarbon gases (ethane, propane, butane) in these shales are significantly higher than in previous wells. The carbon contents of the Y-1 (Allegany County, New York) well, on the other hand, are somewhat lower than predicted from the hydrocarbon gas contents. There is still a positive relationship between the carbon and hydrocarbon gas contents, however. A similar relationship is also apparent between the sulfur and hydrocarbon gas contents. No unusual trends are observed in the porosity values, and a reasonable agreement exists between the measured Hg-intrusion values and those …

A program to design, fabricate, and verify by test a low-cost (in volume production), modularized, practical solar air heater adaptable for new or retrofit space-heating and hot-water applications is described. The unique hardware elements of the SOLAIR II medium-temperature air heater described are the TCA solar collectors, energy transfer module, interconnecting ductwork, and mounting hardware. SOLAIR II is a two-tank domestic hot-water-augmented system. The system is described in detail; market and design analyses are described; fabrication procedures are noted; and design verification tests and results are discussed. The design used for the pre-production lot was essentially the SOLAIR II design and will serve as the basis for future design evaluations as the product is introduced into the commercial market.

Analytical procedures were refined for the Structural Assessment Approach for assessing the Material Control and Accounting systems at facilities that contain special nuclear material. Requirements were established for an efficient, feasible algorithm to be used in evaluating system performance measures that involve the probability of detection. Algorithm requirements to calculate the probability of detection for a given type of adversary and the target set are described.