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931.
Pan Hong Huang Xiaoxiao Zhang Rui Zhang Tao Chen Yanting Hoang Tuan K. A. Wen Guangwu 《Journal of Solid State Electrochemistry》2018,22(11):3557-3568
Journal of Solid State Electrochemistry - With up to fivefold higher in energy density vs. lithium-ion battery, lithium–sulfur (Li–S) battery is a compelling energy storage system,... 相似文献
932.
Linwang Yuan Zhaoyuan Yu Wen Luo Lin Yi Guonian Lü 《Advances in Applied Clifford Algebras》2013,23(2):497-518
Traditional Euclidean geometry-based Geographical Information System (GIS) is not multidimensional unification with weak ability to object expression and analysis of high dimensions. Geometric algebra (GA) can connect different geometric and algebra systems, and provide rigorous and elegant foundation for expression, modeling and analysis in GIS. This paper proposes the implementation methods for system construction and key components of multidimension-unified GIS. Based on such properties as multidimension-unified and coordinate-free of GA, data models, data indexes, and data analysis algorithms for multidimensional vector data, raster and vector field data are developed. This study indicates that GA provides a new mathematical tool for the development of GIS characterized as multidimension-unified expression and computation. For the development of geographical analysis methods, it can represent multidimensional spatio-temporal changes conveniently. 相似文献
933.
934.
A powerful microwave-assisted three-component Knoevenagel-nucleophilic aromatic substitution reaction of 4-halobenzaldehydes, cyanoacetatic acid esters/cyanoacetamides, and cyclic secondary amines has been developed. 相似文献
935.
Tian Ping ZHANG Wen Peng ZHANG 《数学学报(英文版)》2008,24(2):215-222
The main purpose of this paper is to use the properties of the Gauss sums, primitive characters and the mean value of Dirichlet L-functions to study the hybrid mean value of the error term E(n, l, c, q) and the hyper-Kloosterman sums K(h,n+1,q), the asymptotic property of the mean square value ∑^p c=1 E^2(n, 1, c, p), and give two interesting mean value formulae. 相似文献
936.
Yan Zhou Wen‐Na Zhao Lei Han 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(6):o287-o289
The title compound, 4,4′‐(1,1,1,3,3,3‐hexafluoroisopropylidene)diphthalic acid hexahydrate, C19H10F6O8·6H2O, crystallizes in the centrosymmetric space group Pbcn, with half of the diphthalic acid residue and three water molecules in the asymmetric unit. The organic molecule is located on a crystallographic twofold axis. In the solid, cyclic water hexamers in chair conformations have crystallographically imposed inversion symmetry. Strong O—H...O hydrogen bonds between the hexamers and organic molecules result in a unique three‐dimensional supramolecular network [O...O = 2.554 (2)–2.913 (2) Å]. This compound represents the first example of a (3,4,4,10)‐connected four‐nodal supramolecular topology with the Schläfli symbol (43.5.6.7)2(43.52.7)2(43)2(46.56.62.78.814.99). 相似文献
937.
938.
939.
Jian Gong SHI Han Qing Wang Min WANG Guang Xiong ZHOU. Yong Chun YANG Wen Yan HU 《中国化学快报》2000,11(3):225-228
In a previous paper' we reported two optically active pyridine-2, 6 (l H. 3H)-dionealkatoids speranskalines A and B from SPeranskia luberculala (Bge.) (Euphorbiaceae)We report here the isolation and structural elucidation of two novel poly-oxygenbipyridine alkaloids named speranculatines A (l) and B (2) from this plant.The acetone (or methanol) extract of the air-dried whole plants of .q. IllhelT.lllaluwas subjected to column chromatography on St gel to afford a fraction. whichdemonstrate… 相似文献
940.
S. Shanmuga Sundara Raj Hoong‐Kun Fun Zhong‐Lin Lu Wen Xiao Xiao‐Yang Gong Chang‐Ming Gen 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1013-1014
The crystal structure of the title compound, C15H14N2O2·H2O, is in the keto tautomeric form and the configuration at the azomethine C=N double bond is E. The molecule is non‐planar, with a dihedral angle of 27.3 (1)° between the aromatic rings. The crystal structure is stabilized by extensive hydrogen bonding involving the water molecule and hydrazone moiety. 相似文献