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51.
52.
The valence force constants and compliance constants of twenty-six halogenated methanes, silanes and germanes of symmetry C3v and C2v are reported. Correlations have been found between the primary force constants and the nature of the central atom and of the halogen, and the number of attached halogen atoms. Relationships have also been confirmed between the force and compliance constants and the bond lengths and strengths. 相似文献
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54.
J. Aron 《Fresenius' Journal of Analytical Chemistry》1876,15(1):437-444
Ohne Zusammenfassung 相似文献
55.
For a finitely generated moduleE over the Noetherian ringR we consider formulas for the Krull dimension of the symmetric algebraS(E). A result of Huneke and Rossi is re-proved and an effective formula is derived that reads the dimension ofS(E) from a presentation ofE. They provide a first line of obstructions forS(E) to be an integral domain. For algebras of codimension at most four we give methods, including computer-assisted ones, to ascertain whetherS(E) is a Cohen-Macaulay domain.AMS 1980 Mathematics Subject Classification (1985 Revision). Primary 13H10; Secondary 13-04, 13C05, 13C15Partially supported by CNPq, BrazilPartially supported by the NSF 相似文献
56.
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57.
Jaap VanDerWal Johan W. M. Lagerberg Tom M. A. R. Dubbelman John VanSteveninck 《Photochemistry and photobiology》1995,62(4):757-763
Abstract— Loss of clonogenicity of Chinese hamster ovary (CHO) cells, murine L929 fibroblasts and human bladder carcinoma T24 cells caused by photodynamic treatment (PDT) with hematoporphyrin derivative (HPD) is synergistically enhanced by subsequent incubation with rhodamine 123 in the dark. For CHO and L929 cells this synergistic interaction can be explained by an increased uptake of rhodamine 123 as the result of the photodynamic treatment. With aluminum phthalocyanine (AIPc) as photosensitizer only additive effects were observed in the three cell lines. Incubation in the dark with rhodamine 123, followed by a photodynamic treatment with HPD, resulted in an antagonistic interaction with regard to loss of colony formation. With AIPc the combination of treatments resulted in an additive effect with L929 and T24 cells, whereas with CHO cells a slight antagonistic interaction was observed. An antagonistic effect was also observed in model experiments, treating histidine photodynamically with HPD and measuring oxygen consumption. A possible explanation of these results could be an interaction or complex formation of rhodamine 123 with HPD resulting in a diminished singlet oxygen production. With AIPc this does not take place. 相似文献
58.
J. C. Aron 《Foundations of Physics》1986,16(12):1315-1328
The connection with the quarks of the stochastic model proposed in the two preceding papers is studied; the slopes of the baryon trajectories are calculated with reference to the quarks. Suggestions are made for the interpretation of the model (quadratic or linear addition of the contributions to the mass, dependence of the decay on the quantum numbers of the hadrons involved, etc.) and concerning its link with the quarkonium model, which describes the mesons with charm or beauty. The controversial question of the subquantum level is examined. 相似文献
59.
J. C. Aron 《Foundations of Physics》1986,16(11):1159-1210
The definition of mass as a random variable is applied to the study of the decay rates. A decay is assumed possible when the fluctuation of the Gaussian variables involved makes a definite relation satisfied. Computing the probability of this process leads to the determination of the decay amplitude. This calculation, unified for baryons and mesons, is worked out in the lower and medium spectrum (up to2000 MeV for baryons and mesons), and fits to20 MeV the accurate measurements of width and branching ratios. 相似文献
60.
A new hyperspherical coordinate method for performing atom—diatom quantum mechanical collinear reactive scattering calculations is described. The method is applicable at energies for which breakup channels are open. Comparison with previous results and new results at high energies for H H2 are given. The usefulness of this approach is discussed. 相似文献