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61.
在喷气Z pinch内爆等离子体研究中,雪铲模型是一种常用的、比较简单的物理模型。根据实验中提供的电流波形,负载线质量和初始半径,可以通过雪铲模型来估算内爆到心的时刻。根据一维运动方程和不同构形下的解析解以及部分实验结果相结合,讨论了雪铲模型的适用范围。数值计算的内爆时间和实验(Gamble II, Double EAGLE, BLACKJACK 5)测量值符合得较好。结果表明,雪铲模型在喷气Z pinch实验的负载优化设计研究中是很有参考价值的方法。 相似文献
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Three N-3-phenyl-2-propenoyl amino acids were synthesized through interaction between 3-phenyl-2-propenoyl chloride and amino acids in alkaline with a high Yield.Structure of the products were identified by elemental analysis,IR and NMR spectroscopy. 相似文献
64.
There is considerable interest in protein adsorption onto microspheres because of its importance in a wide range of biomedical applications, such as artificial tissues and organs, drug delivery systems, biosensors, solid-phase immunoassays, immunomagnetic cell separation and immobilized enzymes or catalyst. It has been well known that the interaction between proteins and microspheres plays important roles in this process. Major interaction involved in the adsorption can be classified as electrostatic, hydrophobic and hydrogen-bonding. Indeed, adsorption of proteins onto microspheres is a complex process and often can involve many dynamic steps, from the initial attachment of the protein on the surface of microspheres to the equilibrium. Also the conformation of proteins probably occurs to a certain degree of deformation or structural change due to the large area of contact. Recently, much interest has been shown in sulfonated microspheres, since sulfonate-group itself is one of components in bio-bodies, as well as is sensitive to the change of pH or ionic strength. Indeed, so far, scanty investigations have been performed in the full range. Also few researches have involved the data on adsorption rate and the maximum amount of protein adsorbed, or the reversibility of the process and conformational change of protein adsorbed as well.In present study, BSA (bovine serum albumin) was chosen as the model protein and sulfonated PMMA [poly(methyl methacrylate)] microspheres as the matrix to investigate the adsorption process.The purpose is to show some information especially the intrinsic information involved by the adsorption process Adsorption of BSA onto sulfonated microspheres (MS) has been investigated as a function of time, protein concentration and pH. The adsorption appears to be a reversible process and the presence of sulfonate groups can play important roles in the adsorption process, so as to increase the amount of protein adsorbed and influences the interaction of BSA molecules. Fig. 1 also shows that the reciprocation between unadsorbed and adsorbed BSA or rearrangement of adsorbed BSA molecules does not produce visible change in the properties of the adsorbed protein. Close to the isoelectric point of BSA (pI 4.7), the amount of protein adsorbed exhibits a maximum. A higher or lower pH results in the significant decrease of the adsorption amount. This is related to the dependence of BSA conformations at different pH conditions. 相似文献
65.
The immobilization of proteins, especially receptor proteins commonly used in high through-put screening of drugs (HTS), have received great attention in recent years. There are many successful isothermal models for describing the adsorption of protein onto solid surface, such as Langmuir model, Bi-Langmuir model, Fowler model, Freundlich model, Freundlich-Langmuir model and Tekmin model etc. In all these models, Langmuir model was the most favorable one model accepted by many researchers, but the experimental results showed that it was not entirely fit to all adsorption behaviors. So new models were required for describing protein adsorption onto microspheres in different conditions.In our research, a novel isothermal model, including Langmuir and other adsorbing behaviors was presented basing on the holding degree of surface active sites and the interaction styles of protein immobilization. In Langmuir model, the adsorbing amount of protein was described as [PS] =Km[P]/1 + K[P], where [PS] was the concentration of adsorbed protein, [P] was the concentration of freeprotein at equilibrium state, and Km and K was constant. According to the interactions of protein and ligands, there were three patterns in the interactions of protein and ligands. On the similar assumption that the interaction of protein and microspheres were three styles, and based on the definition of the holding degree of surface active sites (Y), three adsorption behaviors could be described as Y K[ P ]φ/ K[P]φ+1 or ln K + φ ln[P] =ln(Y/1-Y) in which [P] was the concentration of free protein at equilibrium state, and φ and K was constant. Different scale of φ presented different adsorption behaviors, especially when φ was 1, the adsorption behavior was Langmuir adsorbing model. Figure I indicated the different adsorbing results in different adsorption behaviors (φ>1, φ<1,and φ=1). 相似文献
66.
Ming Zhao WANG Guan Liang CAI Ling XIA Jun Jian YAO Hong Yan CHEN Zhao Xing MENG Bo Li LIUDepartment of Chemistry Beijing Normal University Beijing Chemical Defense Institute PLA Beijing 《中国化学快报》2004,15(4):495-497
The crystal structures of two potential tumor imaging agents and therapeutic agents -copper(Ⅱ) complexes with salicylidene-tyrosinato Schiff base and nitrogen-donor chelating Lewis base, [Cu(sal-tyr)(bipy)] 1 and [Cu(sal-tyr)(phen)]2CH3OH 2 are presented. Our work is helpful to get deep understanding of novel 64Cu tumor imaging agents and therapeutic agents. 相似文献
67.
68.
LI Zi-jian LIU Ning LIU Zhi-qiang LIU Shu-ying HAN Qi-de ZHANG You-yi . Institute of Vascular Medicine Peking University Third Hospital Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing P. R. China . Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun P. R. China 《高等学校化学研究》2006,22(3):319-323
Introduction Adrenoceptors(ARs),membersofthesuperfami lyofG proteincoupledreceptors,arethemostimpor tantreceptorsinvolvedincardiacregulation[1].ARsin cardiacmuscleincludebothαARsandβARssub types,whileinmostmammalianheart,βARsarethe predominantsubtypes.… 相似文献
69.
Cobalt antidot arrays with different thicknesses are fabricated by rf magnetron sputtering onto porous alumina substrates. Scanning electron microscopy and grazing incidence x-ray diffraction are employed to characterize the morphology and crystal structure of the antidot array, respectively. The temperature dependence of magnetic properties shows that in the temperature range 5K--300K, coercivity and squareness increase firstly, reach their maximum values, then decrease. The anomalous temperature dependences of coercivity and squareness are discussed by considering the pinning effect of the antidot and the magnetocrystalline anisotropy. 相似文献
70.
采用固相反应合成了四羟基苯基卟啉与与Fe^2+,Co^2+金属离子的配合物,在室温下,将其与分子O2作用,提纯后得到两种固态氧合配合物.通过元素分析、红外光谱(IR)、核磁共振氢谱(^1HNMR)、电导、热分析(TG/DTA)、紫外光谱(UV)等测试手段确定了氧合配合物的组成为[Co·THPP·O2](NO3)2·2H2O、[Fe·THPP·O2]Cl2·2H2O],可知1mol配合物吸收了1molO2,采用失重法测定了氧合配合物中的配位氧,确定1mol金属配合物吸收1molO2形成超氧配合物. 相似文献