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901.
902.
Quasi-hereditary algebras can be viewed as a Lie theory approach to the theory of finite dimensional algebras. Motivated by the existence of certain nice bases for representations of semisimple Lie algebras and algebraic groups, we will construct in this paper nice bases for (split) quasi-hereditary algebras and characterize them using these bases. We first introduce the notion of a standardly based algebra, which is a generalized version of a cellular algebra introduced by Graham and Lehrer, and discuss their representation theory. The main result is that an algebra over a commutative local noetherian ring with finite rank is split quasi-hereditary if and only if it is standardly full-based. As an application, we will give an elementary proof of the fact that split symmetric algebras are not quasi-hereditary unless they are semisimple. Finally, some relations between standardly based algebras and cellular algebras are also discussed. 相似文献
903.
本文采用一种优化的硫化助熔剂方法合成了红外上转换材料,这种材料能够在室温下将红外光转换成可见光。这种新工艺在反应效率、生产成本、环境保护、工艺难度等方面均优于传统的热熔工艺。文章给出了红外上转换材料的激励光谱和发射光谱。 相似文献
904.
Zilei Chen Hong Zhang Bing Liu Guosheng Yang Hassan Y. Aboul-Enein Wenbo Wang Ruiyan Ding Hongxia Du Huidong Li 《Chromatographia》2007,66(11-12):887-891
A rapid multi-residue method has been developed for the determination of 16 herbicides in garlic. The analytical procedure is based on prior microwave heating prevention of the generation of sulfur-containing compounds. The garlic samples which had been pretreated were extracted with acetonitrile and cleaned up by solid-phase extraction. The herbicide residues were detected by gas chromatography–mass spectrometry with selected ion monitoring. The recoveries of 16 herbicides ranged from 69.0 to 105.4% with the relative standard deviations (RSD) below 10.1%. The limit of quantification (LOQ) ranged from 0.003 to 0.015 mg kg?1. 相似文献
905.
906.
Du Beiliang 《高校应用数学学报(英文版)》2007,22(2):169-173
A strong partially balanced design SPBD(v, b, k; λ,0) whose b is the maximum number of blocks in all SPBD(v, b, k; λ, 0), as an optimal strong partially balanced design, briefly OSPBD(v, k, λ) is studied. In investigation of authentication codes it has been found that the strong partially balanced design can be used to construct authentication codes. This note investigates the existence of optimal strong partially balanced design OSPBD(v, k, 1) for k = 3 and 4, and shows that there exists an OSPBD(v, k, 1) for any v ≥ k. 相似文献
907.
A percolation study of RTS noise in deep sub-micron MOSFET by Monte Carlo simulation 总被引:2,自引:0,他引:2 下载免费PDF全文
Based on percolation theory and random telegraph signal (RTS) noise generation mechanism, a numerical model for RTS in deep submicron metal-oxide-semiconductor field-effect transistor (MOSFET) was presented, with which the dependence of Tc/Te (where Tc=capture time, Te=emission period ) on energy levels and trap depth with respect to the interface of traps can be simulated. Compared with experimental results, the simulated ones showed a good qualitative agreement. 相似文献
908.
β-环糊精与环氧氯丙烷共聚物的13C-NMR研究 总被引:1,自引:1,他引:0
13C NMR测定了一个系列的环氧氧丙烷与β-环糊精的共聚物,进行了谱峰归属和DEPT谱验证,实验测得2,3-丙二醇基在β-环糊精C(2)-O-位、C(3)-O-位和C(6)-O-位取代的13C NMR化学位移α-取代效应参数,描述了该共聚物分子链的组成和链化学结构特征. 相似文献
909.
Chunheng Liu Yueguang Lu Chunlei Du Xiangang Luo 《International Journal of Infrared and Millimeter Waves》2007,28(12):1115-1122
A aperture-coupled patch antenna is designed with parasitic elements connecting to the rectangle ring on the bottom of antenna
substrate through metal vias, which lead the current induced by patch radiator to the top surface of antenna substrate. Therefore,
the effective radiation is enhanced and higher gain is achieved. The bandwidth is broadened simultaneously due to the structure
of aperture-coupled patch antenna with parasitic elements. Compared to the conventional aperture-coupled patch antenna, the
antenna gain increases averagely 2 dB due to the novel structure. Compared to patch antenna of electromagnetic band-gap, the
dimensions of novel patch antenna greatly decreases, which can be used as element in the array antenna. Two kinds manufactured
antenna are both measured in an anechoic chamber. The good agreements between numerical simulation and experimental prototype
have been obtained. 相似文献
910.
Yttrium forms with CPApM a 1:2 α-complex instantaneously in acidic medium. At pH~5 (buffer solution), the α-complex is transformed to a β-complex with an absorption peak at 755 nm after standing. The transformation reaction is a first-order reaction. The rate constant and the apparent activation energy were found to be 9.67 × 10?1 min?1 and 52.3 kJ·mol?1 respectively. The mechanism of the reaction shows that the β-complex (Y:CPApM=2:4) is formed by combining two molecules of α-complex with the liberation of one proton. 相似文献