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61.
We have developed a novel, high-throughput approach for molecular mass determination of proteins from 14 200 to 116 000 based upon multiplexed, absorbance-based capillary electrophoresis. Via capillary multiplexing, 96 samples were analyzed simultaneously within 30 min. Detection with ultraviolet light obviates the need for protein staining or derivatization. The detection limit of the system was estimated at 5 microg/ml bovine serum albumin (BSA) when sampled from 12.5 mM Tris-HCl. The linear dynamic range was over two orders of magnitude from 5 microg/ml to 1000 microg/ml for BSA. Better than 5% sizing accuracy for protein molecular mass determination and excellent run-to-run and day-to-day reproducibility was obtainable with the described method. 相似文献
62.
Photodissociation dynamics of the CH3 radical at 212.5 nm has been investigated using the H atom Rydberg tagging time-of-flight method with a pure CH3 radical source generated by the photolysis of CH3I at 266 nm. Time-of-flight spectra of the H atom products from the photolysis of both cold and hot methyl radicals have been measured at different photolysis polarizations. Experimental results indicate that the photodissociation of the methyl radical in its ground vibrational state at 212.5 nm excitation occurs on a very fast time scale in comparison with its rotational period, indicating the CH3 dissociation at 212.5 nm occurs on the excited 3s Rydberg state surface. Experimental evidence also shows that the photodissociation of the methyl radical in the nu2 = 1 state of the umbrella mode at 212.5 nm excitation is characteristically different from that in the ground vibrational state. 相似文献
63.
The Turán number of a k-uniform hypergraph H,denoted by exk(n;H),is the maximum number of edges in any k-uniform hypergraph F on n vertices which does not contain H as a subgraph.Let Cl~((k)) denote the family of all k-uniform minimal cycles of length l;S(?1,…,?r) denote the family of hypergraphs consisting of unions of r vertex disjoint minimal cycles of length ?1,…?r,respectively,and Cl~((k))denote a k-uniform linear ... 相似文献
64.
This paper is considering the problem of traveling wave solutions (TWS) for a susceptible-exposed-infectious-recovered (SEIR) epidemic model with discrete diffusion. The threshold condition for the existence and nonexistence of TWS is obtained. More specifically, such kind of solutions are governed by the threshold number ?0. We can find a critical wave speed c? if ?0 > 1, by employing the Schauder's fixed point theorem, limiting argument and two-sided Laplace transform, we confirm that there exists TWS for c > c?, while there exists no TWS for c < c?. We also obtain the nonexistence of TWS for ?0 ≤ 1. At last, we give some biological explanations from the epidemiological perspective. 相似文献
65.
Mathematical Notes - The Boros–Moll polynomials $$P_m(a)$$ arise in the evaluation of a quartic integral. In the past few years, there has been some remarkable research on the properties of... 相似文献
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Jong-Shi Pang 《Mathematical Programming》1993,58(1-3):149-160
This paper is concerned with two well-known families of iterative methods for solving the linear and nonlinear complementarity problems. For the linear complementarity problem, we consider the class of matrix splitting methods and establish, under a finiteness assumption on the number of solutions, a necessary and sufficient condition for the convergence of the sequence of iterates produced. A rate of convergence result for this class of methods is also derived under a stability assumption on the limit solution. For the nonlinear complementarity problem, we establish the convergence of the Newton method under the assumption of a pseudo-regular solution which generalizes Robinson's concept of a strongly regular solution. In both instances, the convergence proofs rely on a common sensitivity result of the linear complementarity problem under perturbation.This work was based on research supported by the National Science Foundation under grant ECS-8717968. 相似文献
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Jin Yi Xu Qian Ran Wei Yi Hua Xiao Ming Wu Qiu Juan Wang Jing Zhang 《中国化学快报》2007,18(3):251-254
A series of 2-alkylbenzimidazole derivatives 9a-n have been designed and synthesized as a novel class of non-peptide angiotensin Ⅱ AT1 receptor antagonists. The synthesized compounds were evaluated for their antagonism of angiotensin Ⅱ, induced contraction in the rabbit thoracic aortic ring and the results showed that compounds 9a, 9g and 9j exhibited potent antagonistic activity of AT1 receptor. 相似文献