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121.
Eva Matousková Charles Stegall 《Proceedings of the American Mathematical Society》1996,124(4):1083-1090
A Banach space is not reflexive if and only if there exist a closed separable subspace of and a convex closed subset of with empty interior which contains translates of all compact sets in . If, moreover, is separable, then it is possible to put .
122.
V. I. Chilin P. G. Dodds A. A. Sedaev F. A. Sukochev 《Transactions of the American Mathematical Society》1996,348(12):4895-4918
We present several characterizations of Kadec-Klee properties in symmetric function spaces on the half-line, based on the -functional of J. Peetre. In addition to the usual Kadec-Klee property, we study those symmetric spaces for which sequential convergence in measure (respectively, local convergence in measure) on the unit sphere coincides with norm convergence.
123.
Jun-ichi Tanaka 《Transactions of the American Mathematical Society》1996,348(10):4113-4129
Using the Stone-\v{C}ech compactification of integers, we introduce a free extension of an almost periodic flow. Together with some properties of outer functions, we see that, in a certain class of ergodic Hardy spaces , , the corresponding subspaces are all singly generated. This shows the existence of maximal weak- Dirichlet algebras, different from of the disc, for which the single generator problem is settled.
124.
Bolis Basit Hans Gü nzler 《Transactions of the American Mathematical Society》1996,348(11):4489-4500
Let be a semigroup and a topological space. Let be an Abelian topological group. The right differences of a function are defined by for . Let be continuous at the identity of for all in a neighbourhood of . We give conditions on or range under which is continuous for any topological space . We also seek conditions on under which we conclude that is continuous at for arbitrary . This led us to introduce new classes of semigroups containing all complete metric and locally countably compact quasitopological groups. In this paper we study these classes and explore their relation with Namioka spaces.
125.
Lämmerhofer M 《Journal of chromatography. A》2005,1068(1):3-30
Enantiomer separations by CE employing nonaqueous conditions are reviewed. The general focus of this article is directed towards solvent effects on chiral recognition and the separation mechanism. After a general discussion of solvent effects on the individual processes involved in CE enantiomer separation, specifics for various selector classes are discussed together with a few applications of enantioselective nonaqueous CE. 相似文献
126.
平行双铂丝微电极用于铁氰化钾电流滴定法测定抗坏血酸的研究 总被引:2,自引:0,他引:2
平行双柱微电极是一种基于可逆氧化还原物质在电极间反馈扩散使得信噪比进一步增大的新型微电极,作者首次将这种电极应用于电流滴定分析中。结果显示,电极间距很小时,终点突跃变敏锐,使灵敏度进一步提高。该方法不需搅拌溶液,单次测量样品量只需约3μ1,是一种有实用价值的新方法。 相似文献
127.
双波长分光光度法同时测定贵金属钯和锇 总被引:4,自引:0,他引:4
本文提出了在对羟基苯基荧光酮和溴化十六烷基三甲烷基甲胺存在下,双波长分光光度法同时测定微量和锇的新方法,在pH=7.6~8.0的磷酸盐介质中,钯和锇的对羟基苯基荧光酮-CTMAB配合物吸收光谱相互重叠,选择测定钯配合物的波长对为580.5nm与530.5nm,测定锇配合物的波长对为553.5nm与604.5nm,钯含量在0~7.0μg/10mL范围内,锇含量在0~9.0μg/mL范围内,与ΔA值呈 相似文献
128.
129.
A system to analyze a complex mixture simultaneously on two different columns after one single on-column injection is described. The splitting device, the possibilities of component identification by searching in a data base for Kovats indices on two different polarity stationary phases, and a practical example of an essential oil analysis are presented. 相似文献
130.
O. Cârja 《Journal of Optimization Theory and Applications》1984,44(3):397-406
In this paper, it is shown that the minimal time function is locally Lipschitz continuous for the control systemx=Ax+u in a Banach spadeE, under either of two conditions:A is linear and generates aC
0-semigroup of bounded linear operators; orA is nonlinear, possibly multivalued, and dissipative. The main tool used for the nonlinear case is a result of Barbu concerning the null controllability of the system. 相似文献