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81.
A combined surface activation and “grafting to” strategy was developed to convert divinylbenzene particles into weak cation exchangers suitable for protein separation. The initial activation step was based on plasma modification with bromoform, which rendered the particles amenable to further reaction with nucleophiles by introducing Br to a surface content of 11.2 atom‐%, as determined by X‐ray photoelectron spectroscopy. Grafting of thiol‐terminated glydicyl methacrylate telomers to freshly plasma activated surfaces was accomplished without the use of added initiator, and the grafting was verified both by reduction in bromine content and the appearance of sulfur‐carbon linkages, showing that the surface grafts were covalently bonded. Following grafting the attached glydicyl methacrylate telomer tentacles were further modified by a two‐step procedure involving hydrolysis to 2,3‐hydroxypropyl groups and conversion of hydroxyl groups to carboxylate functionality by succinic anhydride. The final material was capable of baseline separating four model proteins in 3 min by gradient cation exchange chromatography in a fully aqueous eluent.  相似文献   
82.
非酯类拟除虫菊酯研究进展   总被引:3,自引:0,他引:3  
马军安  黄润秋 《合成化学》1999,7(3):238-251
从结构活性关系和合成方面综述了非酯类拟除虫菊酯的研究进展。  相似文献   
83.
The density function perturbation theory (DFPT) is employed to study the linear thermal expansion and heat capacity at constant pressure (with the quasiharmonic approximation) for wurtzite GaN. The calculated results of linear thermal expansion coefficient and heat capacity at constant pressure are compared with the available experimental data in a wide temperature range. Generally these properties calculated agree well with experimental data except at high temperature, thus it suggests the thermal expansion and heat capacity can be well calculated from this first-principle approach.  相似文献   
84.
对格上Erceg式p.q.(p.)度量的注记   总被引:4,自引:0,他引:4  
本文的主要结果是大幅度地简化了Erceg引入的不分明度量的无点化定义,建立了相应的点式刻画.  相似文献   
85.
In this paper we prove that the equational class generated by bounded BCK‐algebras is the variety generated by the class of finite simple bounded BCK‐algebras. To obtain these results we prove that every simple algebra in the equational class generated by bounded BCK‐algebras is also a relatively simple bounded BCK‐algebra. Moreover, we show that every simple bounded BCK‐algebra can be embedded into a simple integral commutative bounded residuated lattice. We extend our main results to some richer subreducts of the class of integral commutative bounded residuated lattices and to the involutive case. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
86.
We consider a linear sytem in a Banach lattice and provide a simple theorem of the alternative (or Farkas lemma) without the usual closure condition.

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87.
Summary A tool for analyzing spatio-temporal complex physical phenomena was recently proposed by the authors, Aubry et al. [5]. This tool consists in decomposing a spatially and temporally evolving signal into orthogonal temporal modes (temporal “structures”) and orthogonal spatial modes (spatial “structures”) which are coupled. This allows the introduction of a temporal configuration space and a spatial one which are related to each other by an isomorphism. In this paper, we show how such a tool can be used to analyze space-time bifurcations, that is, qualitative changes in both space and time as a parameter varies. The Hopf bifurcation and various spatio-temporal symmetry related bifurcations, such as bifurcations to traveling waves, are studied in detail. In particular, it is shown that symmetry-breaking bifurcations can be detected by analyzing the temporal and spatial eigenspaces of the decomposition which then lose their degeneracy, namely their invariance under the symmetry. Furthermore, we show how an extension of the theory to “quasi-symmetries” permits the treatment of nondegenerate signals and leads to an exponentially decreasing law of the energy spectrum. Examples extracted from numerically obtained solutions of the Kuramoto-Sivashinsky equation, a coupled map lattice, and fully developed turbulence are given to illustrate the theory.  相似文献   
88.
基于系统非线性的红外焦平面非均匀性校正   总被引:4,自引:3,他引:1  
付小宁  殷世民  刘上乾 《光子学报》2002,31(10):1277-1280
采用系统非线性描述和分析方法,从基于红外参考辐射源的校正算法原理入手,提出了一种新的红外焦平面非均匀性校正方法.该算法将每个探测器单元视为一个非线性系统,因此,该算法原理既对基于红外参考辐射源的非均匀性校正算法成立,对基于场景的校正算法在一定条件下也有效,能够适应非均匀性随时间和环境改变而发生缓慢变化的情形,是一种自适应算法.  相似文献   
89.
形体老化与疾病的非线性主成分分析   总被引:2,自引:0,他引:2  
本文把 5个形体老化指标及 13种慢性病指标分别做成两个综合指标 ,再去研究人体老化、疾病与性别及年龄的关系。文中使用非线性主成分法及指出一般线性主成分法的局限性  相似文献   
90.
大小周期正方格子复合结构的光子带隙特性   总被引:1,自引:0,他引:1       下载免费PDF全文
曾隽  潘杰勇  董建文  汪河洲 《物理学报》2006,55(6):2785-2788
把具有宽完全带隙的粗锐复合的周期常数为a的二维正方格子再与周期常数为a2的大周期简单正方格子复合,发现大周期正方格子起缺陷作用.并发现当a2<5a时,缺陷态明显地随入射角度变化.此变化随a2的增大而减少.用FDTD方法计算了其透射和反射谱,结果表明缺陷峰透射率与a2的大小成反比.另外还发现: 缺陷峰结构与大周期正方格子的圆柱直径的关系曲线与a2关系不大.通过调节大周期正方格子的圆柱的直径,可获得单 关键词: 光子晶体 光子能隙 复式结构 缺陷态  相似文献   
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