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991.
氨基硅球表面印迹牛血清白蛋白分离条件的初步探讨 总被引:2,自引:1,他引:1
采用固定模板蛋白表面印迹的方法,在氨丙基衍生的硅球表面制备溶胶-凝胶印迹聚合物识别牛血清白蛋白.以该体系为例对制备蛋白质印迹聚合物的各个基本参数与分离选择性的关系进行研究.结果表明,用正辛基三甲氧基硅烷、氨丙基三乙氧基硅烷、四乙氧基硅烷在摩尔比为42.5:42.5:15,酸度为pH 7.0时进行聚合,并采用01 mol/L NaOH与10%(V/V) HAc-10%(m/V) SDS联用的方法洗脱固定的模板蛋白,由此制备的印迹聚合物的分离选择性能较好;并初步讨论了识别蛋白质的机理. 相似文献
992.
Ming Xue Liu 《数学学报(英文版)》2008,24(9):1471-1474
In this paper, we prove that every operator in a class of contraction operators on a Banach space whose spectrum contains
the unit circle has a nontrivial hyperinvariant subspace.
This research is supported by the Natural Science Foundation of P. R. China (No. 10771039) 相似文献
993.
994.
分别利用白光灯、457-9 nm 氩离子激光、二倍频YAG∶Nd 激光泵浦的诺丹明6G 可调谐窄线宽(0-5 cm -1) 染料激光作为光源, 以单色仪锁相放大器光电倍增管计算机数据采集系统记录光谱, 测量并研究了Y2SiO5∶Eu3 + 晶体的透射光谱、荧光光谱、激发光谱和格位选择荧光光谱。5D0 →7F0,1 ,2 ,3,4 跃迁,30 多根谱线(总数为50 根) 被观察到。在该晶体中Eu3+ 替换Y3+ 离子, 占据两个较低对称性的光学格位, 这两个格位的5D0 7F0 能级跃迁谱线相隔大约只有0-2 nm , 在室温下有一定的光谱关联。并用X射线谱对晶体的晶格常数a , b,c 和晶面角度β进行测量, 测量结果显示掺杂后的晶格常数和未掺杂的Y2SiO5 晶格常数基本一致。 相似文献
995.
Xue Sen FAN Yan Zhen LI Xin Ying ZHANG Xue Yuan HU Jian Ji WANG School of Chemical Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 《中国化学快报》2005,(7)
Room temperature ionic liquids with low melting point (<100℃) salts represent a new class of non-molecular, ionic solvents. Especially those based on the 1-N-alkyl-3- methylimidazolium cations, have shown great promise as an attractive alternative to conventional solvents for catalytic reactions1. On the other hand, FeCl3·6H2O was considered to be an environmentally benign Lewis acid and has been used successfully in several kinds of organic reactions2. Recently we have focused our interes… 相似文献
996.
997.
Chun-fa Li Xue Yang En-min Feng 《应用数学学报(英文版)》2008,24(1):29-40
In this paper, an optimal control problem governed by semilinear parabolic equation which involves the control variable acting on forcing term and coefficients appearing in the higher order derivative terms is formulated and analyzed. The strong variation method, due originally to Mayne et al to solve the optimal control problem of a lumped parameter system, is extended to solve an optimal control problem governed by semilinear parabolic equation, a necessary condition is obtained, the strong variation algorithm for this optimal control problem is presented, and the corresponding convergence result of the algorithm is verified. 相似文献
998.
999.
Gang‐Yin Shi Xue‐Zhi Tang Cai‐Yuan Pan 《Journal of polymer science. Part A, Polymer chemistry》2008,46(7):2390-2401
The tadpole‐shaped amphiphilic copolymers with cyclic polystyrene as the head and a linear poly(N‐isopropylacrylamide) as the tail have been successfully synthesized by combination of reversible addition‐fragmentation chain transfer (RAFT) polymerization and “click” reaction. The synthesis involves two main steps: (1) preparation of a linear acetylene‐terminated PNIPAAM‐b‐PS with a side azido group anchored at the junction between two blocks; (2) intramolecular cyclization reaction to produce the cyclic PS block using “click” chemistry under high dilution. The structures, molecular weights, and molecular weight distributions of the resulted intermediates and the target polymers were characterized by their 1H NMR, FTIR, and gel permeation chromatography. The difference of surface property between tadpole‐shaped polymer and its linear precursor was observed, and the water contact angles on the former surface are larger than that of the latter surface. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2390–2401, 2008 相似文献
1000.
Huan‐Bing Wang Xue‐Si Chen Cai‐Yuan Pan 《Journal of polymer science. Part A, Polymer chemistry》2008,46(4):1388-1401
Novel star‐like hyperbranched polymers with amphiphilic arms were synthesized via three steps. Hyperbranched poly(amido amine)s containing secondary amine and hydroxyl groups were successfully synthesized via Michael addition polymerization of triacrylamide (TT) and 3‐amino‐1,2‐propanediol (APD) with feed molar ratio of 1:2. 1H, 13C, and HSQC NMR techniques were used to clarify polymerization mechanism and the structures of the resultant hyperbranched polymers. Methoxyl poly(ethylene oxide) acrylate (A‐MPEO) and carboxylic acid‐terminated poly(ε‐caprolactone) (PCL) were sequentially reacted with secondary amine and hydroxyl group, and the core–shell structures with poly(1TT‐2APD) as core and two distinguishing polymer chains, PEO and PCL, as shell were constructed. The star‐like hyperbranched polymers have different sizes in dimethyl sulfonate, chloroform, and deionized water, which were characterized by DLS and 1H NMR. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1388–1401, 2008 相似文献