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91.
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J. M. Schultz 《Journal of Polymer Science.Polymer Physics》1992,30(7):785-786
94.
Variable temperature (300-40 K) 4-probe d.c. conduction studies on Cs2[Pt(CN)4](FHF)0.39 and Rb2[Pt(CN)4](FHF)0.40 are described. In these salts T3D occurs at a lower temperature than in K2[Pt(CN)4]Br0.3·3H2O and this is attributed to the absence of an inter-chain network of hydrogen bonded water molecules in the bifluorides. 相似文献
95.
A total synthesis of the cytotoxic phytoalexin juncusol () is described. 相似文献
96.
We determine the local structure of isolated positively charged muonium (Mu+) in heavily doped p-type GaAs based on muon level crossing resonance and zero applied field muon spin depolarization data. These measurements provide the first direct experimental confirmation that Mu+, and by analogy H+, is located within a stretched Ga-As bond. The distances between Mu+ and the nearest neighbor Ga and As atoms are estimated to be 1.83 +/- 0.10 A; and 1.76 +/- 0.10 A, respectively. These results are compared to existing theoretical calculations on the structure of hydrogen in GaAs and additionally provide data on the induced electric field gradients. 相似文献
97.
98.
Fracture mechanisms in bulk metallic glassy materials 总被引:1,自引:0,他引:1
We find that the failure of bulk metallic glassy (BMG) materials follows three modes, i.e., shear fracture with a fracture plane significantly deviating from 45 degrees to the loading direction, normal tensile fracture with a fracture plane perpendicular to the loading direction, or distensile fracture in a break or splitting mode with a fracture plane parallel to the loading direction. The actually occurring type of failure strongly depends on the applied loading mode and the microstructure of the material. Extensive evidence indicates that the Tresca fracture criterion is invalid, and for the first time, three fracture criteria are developed for isotropic materials with high strength, such as advanced BMGs or the newly developed bulk nanostructural materials. 相似文献
99.
Mohd Mustapa MF Harris R Esposito D Chubb NA Mould J Schultz D Driscoll PC Tabor AB 《The Journal of organic chemistry》2003,68(21):8193-8198
Two diastereomeric analogues of ring C of nisin incorporating a novel norlanthionine residue have been synthesized via a triply orthogonal protecting group strategy. A full structural study was carried out by NMR, which elucidated the conformational properties of the two peptides and enabled the identity of each diastereoisomer to be proposed. 相似文献
100.