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排序方式: 共有257条查询结果,搜索用时 15 毫秒
71.
Journal of Chemical Crystallography - The synthesis and structure of a novel ortho-fluoroazobenzene, methyl 4-bromo-3-((2,6-difluorophenyl)diazenyl) benzoate is described. The title molecule... 相似文献
72.
Benedict H. Gross 《Israel Journal of Mathematics》1999,113(1):61-93
In this paper, we develop an algebraic theory of modular forms, for connected, reductive groupsG overQ with the property that every arithmetic subgroup Γ ofG(Q) is finite. This theory includes our previous work [15] on semi-simple groupsG withG(R) compact, as well as the theory of algebraic Hecke characters for Serre tori [20]. The theory of algebraic modular forms
leads to a workable theory of modular forms (modp), which we hope can be used to parameterize odd modular Galois representations.
The theory developed here was inspired by a letter of Serre to Tate in 1987, which has appeared recently [21]. I want to thank
Serre for sending me a copy of this letter, and for many helpful discussions on the topic. 相似文献
73.
Shanshan Qin Lancang Shui Benedict Osuagwu Nikita Denisov Dr. Alexander B. Tesler Prof. Patrik Schmuki 《ChemistryOpen》2022,11(3):e202200010
Titanium dioxide (TiO2) and, in particular, its anatase polymorph, is widely studied for photocatalytic H2 production. In the present work, we examine the importance of reactive facets of anatase crystallites on the photocatalytic H2 evolution from aqueous methanol solutions. For this, we synthesized anatase TiO2 nanocrystals with a large amount of either {001} facets, that is, nanosheets, or {101} facets, that is, octahedral nanocubes, and examined their photocatalytic H2 evolution and then repeated this procedure with samples where Pt co-catalyst is present on all facets. Octahedral nanocubes with abundant {101} facets produce >4 times more H2 than nanosheets enriched in {001} facets if the reaction is carried out under co-catalyst-free conditions. For samples that carry Pt co-catalyst on both {001} and {101} facets, faceting loses entirely its significance. This demonstrates that the beneficial role of faceting, namely the introduction of {101} facets that act as electron transfer mediator is relevant only for co-catalyst-free TiO2 surfaces. 相似文献
74.
In the paper researches of human's greater circulation,
modeled as an electric equivalent circuit were presented. The results of
investigations were obtained by applying of electric equivalent circuit and
compared with data supplied by a physical, hydrodynamic model of the
circulatory system, elaborated by the Biocybernetics Group at the Foundation
of Cardiac Surgery Development (Zabrze, Poland). 相似文献
75.
We describe a novel physical application of the OctTree data structure [P. Meagher, Comput. Graphics Image Process 19(2) (1982) 129–147] in a dynamically tessellating algorithm, in conjunction with an object-oriented, constructive solid geometry library (DOC), to efficiently determine pore size distributions in large multi-particle systems. We apply the DOC library to investigate the evolving dynamics of pore formation in multi-particle systems, such as a mixture of smooth hard cubes and spheres and a collection of frictional soft spheres. We demonstrate that the algorithm is able to provide insight into the effect of structural changes on the porosity network; for example, during the uniaxial compaction of soft spheres, we find the number density of pores increases while the mean volume of the pores decreases. This trend is responsible for a shift in the distribution of the pore volumes to favour smaller volumes. We anticipate that the DOC method will have wider applications in the area of granular materials for studying the changes in pore structure in both experimental and numerical systems as a complement to the analysis of particle packing. 相似文献
76.
Patel DG Benedict JB Kopelman RA Frank NL 《Chemical communications (Cambridge, England)》2005,(17):2208-2210
The single crystals of a closed form spirooxazine spiro[azahomoadamantane-isoquinolinoxazine] were found for the first time to undergo photocoloration processes consistent with photochromism in the single crystalline phase. 相似文献
77.
78.
Benedict?M.?N.?CarterEmail author Alex?B.?Nielsen 《General Relativity and Gravitation》2005,37(9):1629-1634
The static potential for a massless scalar field shares the essential features of the scalar gravitational mode in a tensorial
perturbation analysis about the background solution. Using the fluxbrane construction of [8] we calculate the lowest order
of the static potential of a massless scalar field on a thin brane using series solutions to the scalar field's Klein Gordon
equation and we find that it has the same form as Newton's Law of Gravity. We claim our method will in general provide a quick
and useful check that one may use to see if their model will recover Newton's Law to lowest order on the brane. 相似文献
79.
80.
Benedict Y. K. Ho Leonard Spialter Lee D. Smithson 《Journal of mass spectrometry : JMS》1975,10(8):617-624
High resolution mass spectra have been obtained for a series of methyl, ethyl and phenyl substituted siloxazolidones (cyclic compounds derived from the condensation of organosilane derivatives with amino acids). The effects on the mass spectra of these compounds upon substitution at the saturated ring carbon and at the silicon atom, the migratory nature of the phenyl group on nitrogen, and theextent of biphenyl radical ion formation in the skeletal rearrangement processes have been examined. 相似文献