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221.
F. Archibald Muller 《Foundations of Physics Letters》1992,5(6):591-595
In a recent article [1] M.A. Oliver argues there is a conflict between Einstein's Special Theory of Relativity (STR) and Cosmology. In ascertaining this conflict (see below), Oliver finds allies in Bergmann [2] and Bondi [3]. To resolve this conflict, he proposes to restore the classical (mechanical) concepts of space and time [1, p.666] and an absolute rest-frame. I shall devote a few words (1) to the Principle of Relativity and (2) to the notion of cosmic time in cosmology; this enables me (3) to argue that the alleged conflict between STR and Cosmology is based on a misunderstanding of the Principle of Relativity. (4) Finally I take a critical look at Oliver's allies. 相似文献
222.
A new range of polar imidazolium and phosphate-containing ligands was synthesised from readily available starting materials in high yielding multi-step transformations. These ligands were used to generate Pd catalysts for Suzuki and Heck C–C coupling reactions in organic and organic/aqueous media. The catalysts performed well in aqueous media in the Suzuki reaction and less well in the Heck reaction, related to substrate solubility in the aqueous media. When moving to ionic liquids, the Heck reaction dramatically improved, especially in media compatible with the polar catalysts and the non-polar reagents. In all cases, the catalysts were stable to the formation of Pd black, a form of degradation that frequently befalls Pd catalysts. The catalysts could be successfully recycled without loss of activity. 相似文献
223.
Let D denote the collection of dyadic intervals in the unitinterval. Let be a rearrangement of the dyadic intervals. Westudy the induced operator
where hI is the L normalized Haar function. We find geometricconditions on which are necessary and sufficient for T to bebounded on BMO. We also characterize the rearrangements of theLp normalized Haar system in Lp. 1991 Mathematics Subject Classification:42C20, 43A17, 47B38. 相似文献
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The linear viscoelastic behavior of model rubbertoughened polymer melts has been studied. The most significant influence of the dispersed crosslinked rubber phase on the melt rheology of the blends is the existence of a secondary plateau for the storage modulus G′ at low frequencies. This behavior was ascribed to a percolation phenomenon, leading to the formation of a threedimensional network of inclusions, and contributing to the elasticity at low frequencies of the blend. Two different systems were investigated: (a) a polystyrene matrix with crosslinked and structured latex particles and (b) silicon oil matrices with homogeneous crosslinked PMMA particles. An initial shearing history was found to influence the dynamic mechanical properties of the molten blends and in particular to lower the lowfrequency plateau value for G′. During a subsequent annealing, the plateau modulus increases again. These results are in agreement with the assumption of a particle network. 相似文献
229.
The organocobalt complexes [CoR2L2], with (a) L = PEtPh2 and R = 2,3,5,6- C6HCl4, 2,4,6-C6H2Cl3 and 2,6-C6H3Cl2; and (b) R = 2,4,6-C6H2Cl3 and L = PEt3, PEt2Ph, dpe, 3,5-lut and bipy, have been obtained by reaction of RMgX with [CoCl2L2] or by ligand exchange from [CoR2(PEtPh2)2]. The decompositions in benzene and carbon tetrachloride, and under oxidative conditions have been studied. In benzene solutions, the stability decreases with decrease in the number of chlorine atoms in R. A mixture of RH and RR is obtained in a ratio which depends on the nature of L, the configuration of the complex, and the presence of oxidants. The thermal decomposition takes place through a tricoordinate intermediate “CoR2L”, when L = phosphine, or directly from [CoR2L2] when L = amine. The oxidatively induced decomposition takes place through a cobalt(III) intermediate, which gives RR when L = phosphine or RX (X = H, Br) when L = amine. The process is intramolecular in all cases. 相似文献
230.
The MELANIE project: from a biopsy to automatic protein map interpretation by computer. 总被引:3,自引:0,他引:3
R D Appel D F Hochstrasser M Funk J R Vargas C Pellegrini A F Muller J R Scherrer 《Electrophoresis》1991,12(10):722-735
The goals of the MELANIE project are to determine if disease-associated patterns can be detected in high resolution two-dimensional polyacrylamide gel electrophoresis (HR 2D-PAGE) images and if a diagnosis can be established automatically by computer. The ELSIE/MELANIE system is a set of computer programs which automatically detect, quantify, and compare protein spots shown on HR 2D-PAGE images. Classification programs help the physician to find disease-associated patterns from a given set of two-dimensional gel electrophoresis images and to form diagnostic rules. Prototype expert systems that use these rules to establish a diagnosis from new HR 2D-PAGE images have been developed. They successfully diagnosed cirrhosis of the liver and were able to distinguish a variety of cancer types from biopsies known to be cancerous. 相似文献