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951.
952.
Shi Lei LIU Xiu Bao DU Jing Lin KONG 《中国化学快报》2006,17(1):41-44
Mistletoes are perennial evergreen, semi-parasitic plants growing on branches or stems of deciduous trees. As a medical plant, mistletoe has the reputation of “magic herb” in Europe and has been used for numerous conditions. Its aqueous extractions have… 相似文献
953.
Hansen (Appl. Algebra Eng. Comm. Comput. 14 (2003) 175) uses cohomological methods to find a lower bound for the minimum distance of an evaluation code determined by a reduced complete intersection in
P2. In this paper, we generalize Hansen's results from
P2 to
Pm; we also show that the hypotheses of Hansen (2003) may be weakened. The proof is succinct and follows by combining the Cayley-Bacharach Theorem and the bounds on evaluation codes obtained in Hansen (Zero-Dimensional Schemes (Ravello, 1992), de Gruyter, Berlin, 1994, pp. 205-211). 相似文献
954.
Ralph Howard 《Advances in Mathematics》2006,204(1):241-261
In 1926 Nakajima (= Matsumura) showed that any convex body in R3 with constant width, constant brightness, and boundary of class C2 is a ball. We show that the regularity assumption on the boundary is unnecessary, so that balls are the only convex bodies of constant width and brightness. 相似文献
955.
Yifan Yang 《Advances in Mathematics》2006,204(2):481-508
We obtain defining equations of modular curves X0(N), X1(N), and X(N) by explicitly constructing modular functions using generalized Dedekind eta functions. As applications, we describe a method of obtaining a basis for the space of cusp forms of weight 2 on a congruence subgroup. We also use our model of X0(37) to find explicit modular parameterization of rational elliptic curves of conductor 37. 相似文献
956.
Summary We characterize finitely generated Laskerian modules over a commutative ring in terms of weakly associated prime ideals. 相似文献
957.
958.
Virgil Percec Anatoliy V. Popov Ernesto Ramirez‐Castillo Oliver Weichold 《Journal of polymer science. Part A, Polymer chemistry》2003,41(21):3283-3299
The first example of living radical polymerization of vinyl chloride carried out in water at 25 °C is reported. This polymerization was initiated by iodoform and catalyzed by nascent Cu0 produced by the disproportionation of CuI in the presence of strongly CuII binding ligands such as tris(2‐aminoethyl)amine or polyethyleneimine. The resulting poly(vinyl chloride) was free of structural defects, had controlled molecular weight and narrow molecular weight distribution, contained two ~CHClI active chain ends, and had a higher syndiotacticity (62%) than the one obtained by conventional free‐radical polymerization at the same temperature (56%). This novel polymerization proceeds, most probably, by a combination of competitive pathways that involves activation by single electron transfer mediated by nascent Cu0 and degenerative chain transfer. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3283–3299, 2003 相似文献
959.
H. Bruin 《Topology and its Applications》2005,152(3):182-200
We consider the inverse limit space (I,f) of a unimodal bonding map f as fixed bonding map. If f has a periodic turning point, then (I,f) has a finite non-empty set of asymptotic arc-components. We show how asymptotic arc-components can be determined from the kneading sequence of f. This gives an alternative to the substitution tiling space approach taken by Barge and Diamond [Ergodic Theory Dynamical Systems 21 (2001) 1333]. 相似文献
960.
T. Matsunawa 《Annals of the Institute of Statistical Mathematics》1998,50(4):603-626
Multivariate parametric statistical uncertainty relations are proved to specify multivariate basic parametric statistical models. The relations are expressed by inequalities. They generally show that we cannot exactly determine simultaneously both a function of observation objects and a parametric statistical model in a compound parametric statistical system composed of observations and a model. As special cases of the relations, statistical fundamental equations are presented which are obtained as the conditions of attainment of the equality sign in the relations. Making use of the result, a generalized multivariate exponential family is derived as a family of minimum uncertainty distributions. In the final section, several multivariate distributions are derived as basic multivariate parametric statistical models. 相似文献