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61.
The product of the Asinger reaction between elemental sulfur, n‐butylamine and acetophenone is 8‐(n‐butylaminophenylmethyliden)‐1,2,3,4,5,6,7‐heptathiocane which contains a CS7 ring. A combination of infrared, Raman and inelastic neutron scattering spectroscopies with periodic density functional theory calculations is used to provide a complete assignment of the vibrational spectra of this unusual species. The similarity between the Raman spectra of the compound and that of elemental sulfur is particularly striking. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
62.
We study the Dirac operator D 0 in an external potential V, coupled to a quantized radiation field with energy H f and vector potential A. Our result is a Chernoff-type theorem, i.e., we prove, for the operator D 0+α · A+VH f with λ ∈{0, 1}, that the essential self-adjointness is not affected by the behavior of V at ∞.   相似文献   
63.
The origin and the behaviour of surface charges on the inner walls of differently sized diodes has been investigated by the authors previously. Now, a quantitative treatment is given for the time dependence of the anode current as well as of the potential of an electrode on the outside of the diodes which is characteristic for this method of investigation. The comparison between the results of the calculations and the experimental data shows the models to be adequate on which the calculations are based.  相似文献   
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Ohne Zusammenfassung
Simultaneous determination of boron, chloride, bromide, and iodide in water samples by isotope dilution mass spectrometry
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We develop a new path integral formulation of QCD in radial and axial gauges. This formalism yields free propagators which are free of gauge poles. We find that radial gauges are ghost free. In axial gauges ghosts cannot generally be excluded from the formalism due to the need to fix the residual gauge freedom.  相似文献   
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Summary Carbon disulphide reacts with bis(-mercaptopropylamine)nickel(II) by insertion into the Ni-N bond to yield a planar dithiocarbamate complex, in which the Ni-S bond is broken and a sulphydryl group is formed.  相似文献   
70.
Mohr H  Völkl A 《Electrophoresis》2002,23(13):2130-2137
Peroxisomes (PO) are a heterogeneous population of cell organelles which in mammals are most abundant in liver and kidney. Commonly, differential and density gradient centrifugation are used for their isolation which, however, give only rise to the so-called "heavy" PO with a buoyant density of 1.22-1.24 g/cm(3). Subpopulations other than the heavy PO which are also present in both of these tissues have escaped adequate purification because of their sedimentation characteristics which are close to those of other major organelles, in particular microsomes. Since the purification of these subpopulations has become an essential task in view of the putative importance of peroxisomal subpopulations in the biogenesis of this organelle, alternatives to density gradient centrifugation are required. Recently, we have introduced such a novel approach, named immune free flow electrophoresis (IFFE). IFFE combines the advantages of eletrophoretic separation with the high selectivity of an immune reaction. It makes use of the fact that the electrophoretic mobility of a subcellular particle, complexed with an antibody directed against the cytoplasmic domain of one of its integral membrane proteins is greatly diminished, provided the pH of the electrophoresis buffer is adjusted to pH approximately 8.0, the pI of immunoglobulin G (IgG) molecules. pH-values other than 8.0 proved to be less efficient, probably because IgG molecules only focus at pH 8.0 but are scattered at any other. Applying IFFE to heavy and light mitochondrial as well as microsomal fractions of rat liver not only regular PO (rho = 1.22-1.24 g/cm(3)) but also other subpopulations could be isolated. To substantiate the validity of this approach, we now have subfractionated mouse liver homogenates accordingly. Of the PO subpopulations collected, mainly that obtained from the heavy mitochondrial fraction differed in its composition of matrix and membrane proteins as revealed by immunoblotting. This is in line with the data reported on rat liver thus confirming the potential of IFFE in the isolation of distinct subpopulations of hepatic PO.  相似文献   
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