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Time- and space-resolved electron density measurements, made both above the load coil and in the load coil region of a pulsed inductively coupled plasma, are presented. These data, coupled with argon and calcium emission data, give values for the rates of both radial and vertical transport in the plasma. The data indicate that analyte emission behavior is governed primarily by the rate at which the central channel can be heated through radial transport processes. The electron densities measured in the load coil region agree well with electron densities calculated by models assuming local thermodynamic equilibrium, but agree poorly with non-equilibrium models. Some of the timedependent emission behavior observed in previous work with modulated plasmas is explained by non-uniform heating of argon in the load coil region.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria 相似文献
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DeAngelis A Shurtleff VW Dmitrenko O Fox JM 《Journal of the American Chemical Society》2011,133(6):1650-1653
A catalytic, enantioselective method for the C-H functionalization of indoles by diazo compounds has been achieved. With catalytic amounts of Rh(2)(S-NTTL)(4), the putative Rh-carbene intermediates from α-alkyl-α-diazoesters react with indoles at C(3) to provide α-alkyl-α-indolylacetates in high yield and enantioselectivity. From DFT calculations, a mechanism is proposed that involves a Rh-ylide intermediate with oxocarbenium character. 相似文献
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Richard Shurtleff 《General Relativity and Gravitation》1995,27(5):495-509
Two pairs of parallel geodesic intervals can be generated from two such intervals with a common endpoint by suitable application of parallel transfer. When the connection coefficients are symmetric, a parallelogram-like figure with a closed perimeter can be constructed with the two pairs of sides. When the connection coefficients are asymmetric, combining the two pairs of parallel intervals yields a figure with a coordinate gap. To avoid an open perimeter, a fiber that contains many coordinate-like labels is constructed for each point. Then the gap can occur in the fiber of a single point. Thus a closed figure is obtained even when the connection is asymmetric. A process to obtain the coordinate-like quantities in the fiber of one point with respect to a nearby point is described. A discussion of transformations of the coordinate-like quantities follows and the fundamental curvature-like quantity is obtained. 相似文献
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Richard Shurtleff 《General Relativity and Gravitation》1983,15(5):391-402
A geometric model of a spin one-half charged particle based on a modified version of Weyl's unified model of electromagnetism and gravity is presented. The model predicts a short-range force which we identify with the strong force. A nuclear mass formula similar to the Weizsäcker mass formula provides experimental verification of the geometric approach. 相似文献
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