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排序方式: 共有9109条查询结果,搜索用时 31 毫秒
961.
V. Korepin N. Slavnov 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,5(3):555-557
We discovered a simple quadratic equation, which relates scattering phases of particles on Fermi surface. We consider one-dimensional
Bose gas and XXZ Heisenberg quantum spin chain.
Received: 4 December 1997 / Accepted: 17 March 1998 相似文献
962.
Irradiation caused DNA single-strand breaks in S180 cells in the presence oflaser-hematoporphyrin derivative(HPD).The number of single strand breaks was 3.69 ×10~(10)break dolton~(-1).The analysis of base composition of DNA showed that the effect of laser-HPDirradiation on guanine was the highest,being 5-12 times as high as those of the three others(adenine,cytosine and thymine).It was different from the nature of DNA damage caused by γ-ray irradiation. 相似文献
963.
964.
Artur Heil 《Topology and its Applications》1985,21(3):269-286
We define for every so-called admissible relation r in the Steenrod algebra and for every oriented spherical fibration ξ over a CW-space an exotic characteristic class (mod 2) ε(r)(ξ), which is primitive and vanishes for sphere bundles. The set of exotic classes associated with the universal spherical fibration and the admissible Adem relations are compared with the algebra generators of H1(BSG;2) due to Milgram. Moreover, their behaviour under the action of is computed. Finally, we give a secondary Wu formula for exotic classes of special Poincaré duality spaces. 相似文献
965.
Certain Stiefel-Whitney classes of manifolds with smooth, effective toral actions are shown to be computable in terms of Poincare duals of fixed point sets of isotropy subgroups. As an application the toral degrees of symmetry of certain Dold manifolds are determined. 相似文献
966.
J. -L. Charvet R. Dayras D. Durand O. Lopez D. Cussol D. Dor L. Nalpas A. Van Lauwe C. Volant 《Nuclear Physics A》2004,730(3-4):431-447
A previous analysis of the charge (Z) correlations in the ΔZ−Z plane for 129Xe+natSn central collisions at 32 MeV/n has shown an enhancement in the production of equally sized fragments (low ΔZ) which was interpreted as an evidence for spinodal decomposition. However, the signal is weak and rises the question of the estimation of the uncorrelated yield. After a critical analysis of its robustness, we propose in this paper a new technique to build the uncorrelated yield in the charge correlation function. The application of this method to 129Xe+natSn central collision data at 32, 39, 45 and 50 MeV/n does not show any particular enhancement of the correlation function in any ΔZ bin. 相似文献
967.
A method for the microdetermination of periodate in the presence of iodate is presented. It is based on reduction of periodate to iodate by leucothionine generated in situ by photochemical reaction between EDTA and blue thionine. Biamperometric curves are used for evaluation, representing reduction time for the periodate versus the current generated in the oxidation of the Tred in excess after the end-point. A polarographic study of the process is presented. An applied potential of 100 mV is suitable for the biamperometric measurements with Pt—Pt electrodes. The method is applicable for 0.4–45 ppm periodate. Iodate does not interfere up to IO-3 : IO-4 ratios of 100:1. 相似文献
968.
Explicit examples of finite subgroups of the group of homotopy classes of self-homotopy equivalences of some flat Riemannian manifolds which cannot be lifted to effective actions are given. It is also shown that no finite subgroups of the kernel of π0(Homeo(M))→Out π1(M) can be lifted back to Homeo(M), for a large class of flat manifolds M. Some results of an earlier paper by the authors are refined and related to recent work of R. Schoen and S.T. Yau. 相似文献
969.
Precipitate-type electrodes (benzidine sulfate or phosphate and hexammino-cobalt(III) nitrate in silicone rubber), and liquid ion-exchanger electrodes based on quaternary ammonium and phosphonium and triphenyltin salts were tested for the assay of phosphate ions. Good sensitivity was achieved with the phosphonium and triphenyltin salts, but both lacked sufficient selectivity for routine-assays. 相似文献
970.
Amperometric oxygen electrodes are useful transducers for enzymatic analyses. One must, however, account for contributions from oxygen incorporation or depletion caused by sample introduction, stirring and diffusion, or non-enzymatic reactions, as well as for instrumental response time. Examples of various characteristics of these contributions are shown and discussed from a theoretical basis. 相似文献