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131.
María Yolanda Ríos M. Ángeles Ramírez‐Cisneros Ismael León‐Rivera Samuel Estrada‐Soto Gabriel Navarrete‐Vázquez A. Berenice Aguilar‐Guadarrama 《Magnetic resonance in chemistry : MRC》2012,50(4):329-331
Complete 1H and 13C NMR chemical shift assignments for 3,4‐seco‐lup‐20(29)‐en‐3‐oic acid ( 1 ) have been established by means of two‐dimensional COSY, HSQC, HMBC and NOESY spectroscopic experiments as well as by analysis of MS data. Compound 1 was isolated from Decatropis bicolor (Zucc.) Radlk. (Rutaceae) in addition to six coumarins and one alkaloid of known structure. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
132.
The Alperin Weight Conjecture was stated by J. Alperin in 1986 and constitutes one of the main problems in the representation
theory of finite groups. In this paper, we provide a reduction to simple groups and as an application we prove the conjecture
in several cases. 相似文献
133.
134.
The presentation of the quantum cohomology of the moduli spaceof stable vector bundles of rank two and odd degree with fixeddeterminant over a Riemann surface of genus g > 2 is obtained.The argument avoids the use of gauge theory, providing an alternativeproof to that given by the author in Duke Math. J. 98 (1999)525540. 2000 Mathematics Subject Classification 14N35(primary); 14H60, 53D45 (secondary). 相似文献
135.
Gabriel Nagy 《Proceedings of the American Mathematical Society》2002,130(4):1065-1071
We prove that the value of the quasi-trace on an idempotent element in an AW*-factor of type is the same as the dimension of its left (or right) support.
136.
Gabriel Navarro 《Transactions of the American Mathematical Society》2002,354(7):2759-2773
Suppose that is a finite -solvable group. We associate to every irreducible complex character of a canonical pair , where is a -subgroup of and , uniquely determined by up to -conjugacy. This pair behaves as a Green vertex and partitions into ``families" of characters. Using the pair , we give a canonical choice of a certain -radical subgroup of and a character associated to which was predicted by some conjecture of G. R. Robinson.
137.
This article describes the roadside traffic noise surveys conducted in heavily built-up urban areas in Hong Kong. Noise measurements were carried out along 18 major roads in 1999. The measurement data included L10, L50, L90, Leq, Lmax, the number of light vehicles, the number of heavy vehicles, the total traffic flow, and the average speed of vehicles. Statistical analysis using the analysis of variance (ANOVA) and Tukey test (p<0.05) reveals that the total traffic flow and the number of heavy vehicles are the most significant factors of urban traffic noise. Multiple regression was used to derive a set of empirical formulas for predicting L10 noise level due to road traffic. The accuracy of these empirical formulas is quantified and compared to that of another widely used prediction model in Hong Kong--the Calculation of Road Traffic Noise. The applicability of the selected multiple regression model is validated by the noise measurements performed in the winter of 2000. 相似文献
138.
Viciu L Caruntu G Royant N Koenig J Zhou WL Kodenkandath TA Wiley JB 《Inorganic chemistry》2002,41(13):3385-3388
A new series of transition-metal oxyhalides (MCl)LaNb(2)O(7) (M = Cr, Mn, Fe, Co) have been prepared by a simple topochemical route. Layered perovskite hosts (ALaNb(2)O(7), A = Li, Na, K or Rb) were reacted with the corresponding anhydrous metal halides under mild reaction conditions (<400 degrees C). The compounds were examined by X-ray powder diffraction; the series appears to be isostructural with (CuCl)LaNb(2)O(7), and the layer spacings, with the exception of M = Co, follow the trend expected from transition-metal cationic radii. Thermal analysis with differential scanning calorimetry (DSC) shows the materials to be metastable where all four compounds decompose exothermically above 690 degrees C. 相似文献
139.
Here we describe the synthesis of a mesoporous composite material using the self-assembly of well defined tubular building blocks obtained from the exfoliation of [Nb6O17(4-)]n sheets. 相似文献
140.