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71.
72.
If X1, X2 are independent with common density g symmetric about zero, then for all real α. We provide a counter example to show that the converse is false and thus settle a question posed by Burdick (1972). 相似文献
73.
74.
75.
This paper investigates space-times which admit anr-dimensional Lie algebra of homothetic vector fields at least one of which is proer homothetic. The situation is resolved completely ifr 6 and some general results are given whenr 5. Some applications to the study of affine vector fields in space-times are also given and the maximum dimension of this latter algebra is computed and corrects an earlier error. 相似文献
76.
Bellotti R Cafagna F Caliccio M De Cataldo G De Marzo C Erriquez O Favuzzi C Giglietto N Nappi E Spinelli P Cecchini S Fabbri M Giacomelli G Mandrioli G Matteuzzi P Pal B Patrizii L Predieri F Sanzani GL Serra P Spurio M Ahlen S Ficenec D Hazen E Klein S Levin D Marin A Stone JL Sulak LR Worstell W Barish B Coutu S Hong J Liu G Peck C Solie D Steele J Lane C Steinberg R Battistoni G Bilokon H Bloise C Campana P Chiarella V Forti C Grillo A Iarocci E Marini A Patera V Reynoldson J Ronga F 《Physical review D: Particles and fields》1990,42(5):1396-1403
77.
Molecular receptors consisting of two parallel-disposed terpy-M-Cl units (M = Pd2+, Pt2+) are used to form host-guest adducts with aromatic molecules and with neutral square-planar Pt2+ complexes. Host-guest formation is controlled by several factors including pi-pi interactions and, in some cases, weak Pt-Pt interactions between the host and the guest. This latter interaction was examined by comparing the host-guest stability of adducts formed by isoelectronic Pt2+ and Au3+ complexes with the Pt2+ receptor. Consistently, the former is more stable. 相似文献
78.
The amount of platinum dissolved from platinum apparatus used for dissolving silicate materials to obtain solutions for analysis has been determined. The study included apparatus made from an alloy containing 95 % platinum and 5 % gold. The affinity of iron and platinum was investigated, together with the problem of removing iron from platinum after the latter has been contaminated during fusions. The behaviour of platinum in a classical scheme for the analysis of silicate materials was investigated and the distribution of the platinum in various precipitates established. Platinum has been found to interfere in commonly used methods for the determination of silica, aluminium, iron, titanium, calcium and magnesium. 相似文献
79.
80.
Kent P. Steele Dongjaw Tzeng William P. Weber 《Journal of organometallic chemistry》1982,231(4):291-298
Photochemically-generated dimethylsilylene is found in competition experiments to insert preferentially into oxygenhydrogen bonds of alcohols compared to either siliconhydrogen bonds of silanes or siliconoxygen bonds of alkoxysilanes. This selectivity for OH bonds compared to SiH bonds is quite high in tetrahydrofuran and in dilute hydrocarbon solutions. However, it decreases in more concentrated hydrocarbon solutions. These effects are discussed in terms of aggregation of alcohols, hydrogen bonding, and solvent-mediated dimethylsilylene reactivity. 相似文献