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121.
Katalin Gyarmati 《Periodica Mathematica Hungarica》2006,52(2):9-26
Summary We study the pseudorandom properties of the power generator (which includes as special cases the RSA generator and the Blum--Blum--Shub
generator). In order to estimate the pseudorandom measures character sums with exponential functions are used. 相似文献
122.
György Keglevich Andrea Kerényi Helga Szelke Timea Imre 《Transition Metal Chemistry》2006,31(3):306-309
Reaction of a series of P-amino and P-cycloalkoxy dibenzo[c.e][1,2]oxaphosphorines (1), (3) and (5) with cis-bis(benzonitrile)dichloroplatinum(II) afforded the title bis(dibenzooxaphosphorino) complexes (2), (4) and (6), respectively. In the case of chiral P-substituents, the complexes (4) and (6) were obtained in homo and heterochiral forms. Stereospecific 1J(195Pt–P) couplings found in the 31P-n.m.r. spectra of the products (2), (4) and (6) suggested the cis orientation of the identical substituents. 相似文献
123.
124.
Modifying the shape of FB-spline curves 总被引:1,自引:0,他引:1
FB-spline curves are the unification of recently developed trigonometric CB-spline and hyperbolic HB-spline curves, including the classical B-spline curves. These generalized curves overcome some restrictions of B-spline curves and allow to design some important curves like helix, cycloids or catenary. Their properties, however, have been studied only theoretically. In this paper practical shape modification algorithms of FB-spline curves are discussed, including the geometrical effects of the alteration of shape parameters, which are essential from the users’ point of view. 相似文献
125.
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127.
Thin-layer Chromatographic behavior of 22 steroids were compared in five systems of different compositions and polarities. Some of the steroids studied are new: mainly aromatic steroid derivatives substituted with hydroxy on carbon-2 or carbon-4, or both carbon-2 and carbon-4 of the aromatic ring: from a biological point of view they are of importance as metabolic intermediates. 相似文献
128.
J. Gerse J. Kern J. Imre L. Zsinka 《Journal of Radioanalytical and Nuclear Chemistry》1988,128(1):71-79
Three SUBLITECHR technetium generators were milked and generator products were tested for 5 d. Radionuclidic and radiochemical purity, pH of sodium pertechnetate solutions were -emitting impurities and pirogenity were not carried out. We can summarize that generators were running efficiently during our test period and in all cases the pertechnetate produced met the requirements of the European Pharmacopoeia. 相似文献
129.
The pyrolysis of the long (C≥5) chain n-alkanes is reviewed with emphasis on the radical chain mechanism and on the reactions of the intermediate alkyl radicals. The effects of the experimental conditions and conversion on the types and distributions of the final products are also evaluated. The Arrhenius rate parameters are summarized for both the elementary steps and the overall decomposition reactions. 相似文献
130.