The BNL Neutral Beam Development Group has been active in the program for the development of high energy, high power neutral beam systems since 1973. These injectors are based on the production, acceleration and neutralization of negative hydrogen or deuterium ions and are supposed to be used for plasma heating and current drive in the next generation of fusion devices. Over the span of 10 years the group has studied plasma-surface type of negative hydrogen ion sources, transport and acceleration of negative ion beams and neutralization of negative ions in gases and plasmas. As the required source parameters (current, pulse length, efficiency) were changing over this period of time, the group developed several types of sources, resulting finally in the design of a steady state device operating with an excellent gas efficiency and having the possibility of scaling-up to the size necessary for a high power neutral beam system. The funding of this program was, however, terminated in FY 83 before the neutral beam performance of the source could be shown. This report will present a summary of the BNL effort over the past ten years, with most emphasis on achievements in FY 83, including the description of the 2 …

It was demonstrated that the nature of the initial solvent used to extract the silver neodecanoate during synthesis or to render it into solution for ink formulation has a profound influence on fired film properties. The lower the boiling point of the initial solvent, the more of it was removed during rotary vacuum evaporation, and the less effect it had on fired film properties. Benzene and tetrahydrofuran were superior to xylene and toluene, and inks which used them in their preparation produced fired films with excellent appearance and adhesion if the proper firing sequence was used. The best films also had electrical resistivities very close to that of pure silver, which indicates that near theoretical density was achieved. Platinum and palladium metallo-organic compounds were investigated so that fired films with good solder leach resistance could be produced. Six metallo-organic compounds were synthesized, four of them were used to make inks, and the properties of films made from these inks were evaluated. The most promising compound evaluated was Pt 2,4 pentane dionate, but additional studies are required.

The Westinghouse Electric Corporation has undertaken to investigate, develop, and characterize laser-assisted processing techniques utilized to produce the fine line, thin metal grid structures that are required to fabricate high-efficiency solar cells. Two basic techniques for metal deposition will be investigated, as follows: (1) photochemical decomposition of liquid or gas phase organometallic compounds utilizing either a focused, CW ultraviolet laser (System 1) or a mask and ultraviolet flood illumination, such as that provided by a repetitively pulsed, defocused excimer laser (System 2), for pattern definition, and (2) thermal deposition of metals from organometallic solutions or vapors utilizing a focused, CW laser beam as a local heat source to draw the metallization pattern. The purpose of this contract is to investigate the various existing laser-assisted film deposition techniques in order to develop a new, cost-effective technology for solar cell metallization. The tasks that will be performed in the conduct of these investigations are detailed. In the first three months of this contract, a comprehensive literature search has been carried out on the various state-of-the-art laser-assisted techniques for metal deposition, including laser chemical vapor deposition and laser photolysis of organometallics, as well as laser-enhanced electroplating. A compact system for the experiments involving …

No new field-ionization data was obtained this quarter. For preasphaltenes, elemental analysis data was obtained on Kentucky and Wyodak preasphaltene samples. In conjunction with the preasphaltene work, solubility and thin-layer chromatography experiments were performed. The results indicated that basic alumina would not be useful as a general stationary phase for the separation of preasphaltenes. Several experiments were carried out with Chromasorb T, and the results showed it would be an adequate substitute for Fluoropak. The hydrocarbons in a sample from Pittsburgh Energy Technology Center were separated by the number of double bonds. The optimum mobile phases for the separation of monohydroxyl aromatics and dihydroxyl aromatics by reversed-phase liquid chromatography were obtained. In addition, a means of predicting retention in normal-phase chromatography was considered, and a NO/sub 2/ high-performance chromatographic column showed promise for the separation of compound classes. 6 references, 4 figures, 7 tables.

Studies of the oxidation and gasification of oil shale char were extended to an investigation of the effects of mineral catalysis. Six shales with differing mineral compositions were studied, including samples from the saline zone in the Western Colorado and from the Antrim shales of Michigan. Oxidation kinetics data, corrected for mass transfer effects, were compared for all six samples. A high assay shale from Utah and a sample from the saline zone were found to have the highest oxidation rates. By examining the data for shales which were water leached and thermally pretreated, it was concluded that both NaO and CaO act as oxidation catalysts. However, as a result of mineral decomposition experiments conducted with a sample from the C-a lease tract, it appears as though the ankeritic dolomite fraction will not decompose as long as there is a minimal CO/sub 2/ over pressure. Rather, low temperature silication reactions appear to take place once the temperature exceeds 925/sup 0/K. An extensive evaluation was also completed for the gasification of an Antrim shale from Michigan. Both the rates of CO/sub 2/ and steam gasification of the char were found to be markedly lower than that observed for a shale sample …

The Rotating Target Neutron Source-II (RTNS-II) facility is the most intense continuous source of 14-MeV neutrons in the world. It is used to study the effects of fast neutrons on materials, to determine their suitability for use in fusion reactors. In RTNS-II, a water-cooled rotating target coated with titanium tritide is bombarded with deuterons. A small fraction of the incident deuterons fuse with the tritons in the target, producing 14.3-MeV neutrons. At present the neutron flux is substantially less than what a fusion test reactor would generate. This report examines the possibilities for upgrading RTNS targets to produce reactor-level neutron fluxes (or more). It is shown that the existing targets are operating near their thermal limit. However, modifications in target design and operating conditions are possible which could reasonably support up to a 30-fold increase in peak neutron flux (approx. 3 x 10/sup 14/ neutrons/cm/sup 2/-sec, or 6 MW/m/sup 2/). The irradiated volume could also be increased, if desired. It seems likely that with some research and experimentation with palladium underlayers, target cladding/overcoating, and/or in-situ retritiding, an acceptable target lifetime can still be achieved at this greatly upgraded neutron flux. The proposed target modifications consist of a number of significant …

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