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排序方式: 共有737条查询结果,搜索用时 93 毫秒
91.
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93.
E. Ühlein P. Kratochvíl H. H. Pfeiffer R. Hähnel A. Sippel E. Best H. Bergmann 《Colloid and polymer science》1967,220(2):171-192
Ohne Zusammenfassung 相似文献
94.
The gross structure oscillations recently observed in heavy-ion elastic or inelastic scattering and fusion cross sections are here analyzed in terms of nuclear surface (creep) wave resonances. Their dispersion curves characterize these waves as being of Rayleigh or of Whispering-Gallery type. 相似文献
95.
E. Ühlein 《Colloid and polymer science》1956,147(3):161-162
Ohne Zusammenfassung 相似文献
96.
William J. Pervin 《Mathematische Annalen》1962,147(4):313-315
97.
A.S Üstünel 《Journal of Functional Analysis》1982,47(2):143-152
98.
99.
A new method to determine quasi diabatic (QD) CASSCF states is presented. The adiabatic states are subjected to a unitary transformation resulting from diagonalization of a state-selection operator. The latter is constructed from the overlap of the adiabatic states with a suitable set of reference states. The multi-state (MS) CASPT2 method is used to account for the dynamical correlation effects in an approach where the QD-CASSCF wave functions are used as reference states. The procedure is applied to avoided crossings in excited states of BeH, LiO and ozone. The advantages of the proposed formulation are discussed. 相似文献
100.
Al-Cu-Fe alloys were prepared by mechanical alloying starting from elemental powders in a high-energy planetary ball mill. Three different alloy compositions with the same c Cu : c Fe ratio of 2:1 but different aluminium contents, that is Al55Cu30Fe15, Al63Cu25Fe12 and Al70Cu20Fe10, were investigated. A sequence of solid-state reactions resulting in quasicrystalline phase formation in Al63Cu25Fe12 proceeds during milling and during annealing of the as-milled powder. These reactions were studied by X-ray diffraction, transmission electron microscopy and differential scanning calorimetry. In order to form an aluminium-matrix composite, Al63Cu25Fe12 single-phase quasicrystalline powders were blended with different amounts of aluminium. In an intermediate milling step the powder blend was homogenized. The powders were consolidated by hot extrusion. The bulk samples revealed a homogeneous dispersion of the particles in the matrix but a rather heterogeneous size distribution. The mechanical properties at room temperature were tested by constant-rate compression tests. A rule-of-mixtures dependence of the ultimate strength and the yield strength on the volume fraction of the quasicrystalline particles was found. 相似文献