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[en] The complex PPN⁺ CpV(CO)₃H^- (Cp=eta⁵-C₅H₅ and PPN = (Ph₃P)₂) was prepared in 70% yield and its physical properties and chemical reactions investigated. PPN⁺ CpV(CO)₃H^- reacts with a wide range of organic halides. The organometallic products of these reactions are the vanadium halides PPN⁺[CpV(C)₃X]^- and in some cases the binuclear bridging hydride PPN⁺ [CpV(CO)₃]₂H^-. The borohydride salt PPN⁺[CpV(CO)₃BH₄]^- has also been prepared. The reaction between CpV(CO)₃H^- and organic halides was investigated and compared with halide reductions carried out using tri-n-butyltin hydride. Results demonstrate that in almost all cases, the reduction reaction proceeds via free radical intermediates which are generated in a chain process, and are trapped by hydrogen transfer from CpV(CO)₃H^-. Sodium amalgam reduction of CpRh(CO)₂ or a mixture of CpRh(CO)₂ and CpCo(CO)₂ affords two new anions, PPN⁺ [Cp₂Rh₃(CO)₄]^- and PPN⁺[Cp₂RhCo(CO)₂]^-. CpMo(CO)₃H reacts with CpMo(CO)₃R (R=CH₃,C₂H₅, CH₂C₆H₅) at 25 to 50⁰C to produce aldehyde RCHO and the dimers [CpMo(CO)₃]₂ and [CpMo(CO)₂]₂. In general, CpV(CO)₃H^- appears to transfer a hydrogen atom to the metal radical anion formed in an electron transfer process, whereas CpMo(CO)₃H transfers hydride in a 2-electron process to a vacant coordination site. The chemical consequences are that CpV(CO)₃H^- generally reacts with metal alkyls to give alkanes via intermediate alkyl hydride species whereas CpMo(CO)₃H reacts with metal alkyls to produce aldehyde, via an intermediate acyl hydride species

[en] A tailored periodic spatial magnetic-field variation superimposed on the magnetically supported plasma column of a linear turbulent-heating device leads to electron trapping which, via ''trapped electron'' modes and other instabilities, increases the level of low-frequency turbulence. Impressive increases in ion heating have been observed for only modest strengths of the superimposed field

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[en] In the past year, the linear turbulent-heating device was modified and improved, three new major diagnostic systems were put into operation, and most important of all, the catalytic turbulent-heating by spatial magnetic field variations was successfully demonstrated. One basic goal is to increase the efficiency of coupling energy into low frequency modes which in turn heat the ions selectively. The experimental results strongly indicate this is the case. It is conceivable that ion heating can be improved by the presence of either intentional or unavoidable magnetic field variations

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[en] A floor module used to support a centrifuge machine is a steel framework embedded in a 2-ft (610-mm) thick concrete slab. This steel framework is made up of four cylindrical hollow sockets tied together with four S-beams to form a square pattern. In the event of a centrifuge machine wreck, large forces are transmitted from the machine to the corner sockets (through connecting steel lugs) and to the concrete slab. The floor modules are loaded with a combination of torsion and shear forces in the plane of the floor slab. Precisely how these wreck loads are transmitted to, and reacted by, the floor modules and the surrounding concrete was the scope of a series of full-scale tests performed at the DOE Gas Centrifuge Enrichment Plant (GCEP) located near Piketon, Ohio. This report describes the tests and the results of the data reduction to date

[en] The propagation of ion acoustic wave (IAW) in a double-electron-temperature plasma is investigated both experimentally and theoretically. It is found that the presence of even a small fraction of the lower-electron-temperature component can dominate the behavior of the waves. The results have important implications both for the use of IAW as a diagnostic tool for measuring electron temperature and for the interpretation of turbulent IAW spectra. (auth)

[en] CpMo(CO)₃H (1) and CpMo(CO)₃R (2) (R = CH₃, C₂H₅, CH₂C₆H₅, CD₃, CD₂C₆D₅) undergo a clean and quantitative reaction which yields aldehyde R-CH (3) + dimers Cp₂Mo₂(CO)₄ (4) and Cp₂Mo₂(CO)₆. The methyl and ethyl complexes (2) are converted into their corresponding aldehydes at temperatures between 25 and 50⁰C, the ethyl complex reacting more rapidly. Yields are quantitative and no trace of alkanes is observed; rate constants are listed. The deuterium isotope effects are not evaluated. Three possible mechanisms for these reactions are postulated. 2 figures, 1 table