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101.
PhGeCl3 reacts with Na{[OP(OEt)2]3CoCp} to give the six-coordinate complex PhCl2Ge{[OP(OEt)2]3CoCp}, characterised spectroscopically and by an X-ray crystal structure determination which showed a firmly-attached tridentate ligand [Ge-O 1.973(2) Å].  相似文献   
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The ingredients required to create a magnetic field in the early Universe are identified, and compared with Sakharov's conditions for baryogenesis. It is also shown that a long range coherent magnetic field is not generated by the classical rolling Higgs vacuum expectation value during the electroweak phase transition.  相似文献   
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This paper presents methods for designing and recording optimal computer-generated diffractive optical elements. The design method is based on an analytic ray-tracing procedure for minimizing aberrations. The recording involves computer-generated masks and multiple lithographic processes in order to form reflective and transmissive multilevel, surface relief-phase, diffractive elements. As a result, the elements can have high diffraction efficiencies over a broad range of incidence angles. Even generalized diffractive elements that operate with highly uniform diffraction efficiency and polychromatic radiation can be designed and recorded by optimizing the shape and height of the relief gratings. To illustrate the effectiveness of the diffractive optical elements, they have been incorporated into a number of applications, involving visible as well as infra-red radiation. Some that deal with coordinate transformation, beam shaping, and polarization control are briefly reviewed.  相似文献   
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We present data on momentum correlations both in and out of the production plane for the reactions π+p→πf+(π+n) and π?p→πf?(π?Δ++). The dissociation products show strikingly similar transverse momentum distributions which in terms of exchange models suggest an equal amount of pion and baryon exchange. For both reactions, we find an approximate factorization in the projectile frame between the transverse momentum of πf and the longitudinal momenta of the dissociation products. Exchange models predict this result equally in both reactions, but it appears much more clearly in the Δ reaction. Finally, we relate the observed longitudinal and transverse momentum distributions in a way suggested by an isotropic decay model.  相似文献   
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Summary This paper continues [2]. We show that the sets of infinitely divisible elements of the Delphic semigroups + (of positive renewal sequences) and P (of standard p-functions) are additively convex, and do a Choquet analysis in each case. We draw up the (M, m) diagram for members of , and deduce from it that the product topology on is metrizable. Finally we look at the arithmetic of , showing that the simples are residual in it, and partially identifying I 0, the set of infinitely divisible elements without simple factors. Many examples are given.I am indebted to Professor D. G. Kendall for his constant help and encouragement in the course of the research leading to this paper and [2].  相似文献   
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