硅烷化剂-苯基二甲基氯硅烷的合成研究

苯基二甲基氯硅烷是一种空间位阻封闭剂，保护剂。由于分子中的Si-Cl键很活泼所以能与有机化合物中含活泼氢的官能团（如羟基、羰基、羧基、氨基等）反应，取代其中的活泼氢，其衍生物在酸及碱条件下比三甲基醚类更为稳定。有机化合物中的活泼氢被硅烷基取代后，变成化学稳定性很高的中间产物，且其它基团的反应活性不受影响；反应结束后，通过催化水解或醇解反应，可在不影响分子中其余部分前提下脱去硅烷基，恢复被保护的活泼氢。     

HPLC-MS/MS多反应监测法测定藜蒿中绿原酸的含量

藜蒿(Artem isia SelengensisTurcz)是菊科蒿属草本植物,主要生长在江西鄱阳湖区域的草滩上,在我国其它地区也有分布。该植物不仅可食用,风味独特,是长江中下游地区的地方特色蔬菜,而且可作药用,具有抑菌、消炎、抗氧化等功效,是一种具有重要开发价值的植物资源[1]。近年来许多     

Thin-Film Morphologies of Random Copolymers as Functions of Thermal History

Series polymers of butyl methacrylate with various contents of 3-(trimethoxysilyl)propyl methacrylate (MSMA) that introduces crosslinking networks among the macromolecules upon hydrolysis and self-condensation have been synthesized by free radical polymerization, and the influence of crosslinking density on the film properties has been examined. The polymer solutions were spin-cast over a layer of polystyrene brush to yield homogeneous polymer films. When the films of about 30 nm thick were exposed to moisture and then heated at 60 degrees C for hydrolysis and self-condensation of MSMA groups, the initially flat surfaces became slightly coarser but without apparent dewetting. Further annealing at 140 degrees C resulted in dewetting of the thin films, whose morphologies in thermodynamic equilibrium were related to the chemical compositions of the polymers. The polymers having higher contents of MSMA exhibited significantly reduced dewetting at the high temperature, due to the higher density of crosslinking networks that restricted the molecular mobility. In contrast to the thin films of about 30 nm thick, thicker films (about 100 nm) showed only a slight dewetting, even non-dewetting at the elevated temperature. Copyright 2001 Academic Press.     

Banach空间中Volterra非线性积分方程的Carathéodory解

本文在相当弱的条件下研究Ｂａｎａｃｈ空间中Ｖｏｌｔｅｒｒａ非线性积分方程的Ｃａｒａｔｈｅｏｄｏｒｙ解的存在性,证明方法简洁且与现有文献不同．     

Analysis of simple shear endochronic equations for finite plastic deformation

IntroductionThestress_strainbehaviorofmaterialswithfiniteplasticdeformationisaninterestingissue ,onwhichsignificantprogresshasbeenmadethroughboththephenomenologicalandphysicalapproaches.Thephenomenologicalapproachisbasedoncontinuummechanicsofplasticity .Ithasitsadvantageinsolvingcomplicatedproblemsbecauseofitssimplicity .Mostofphenomenologicaltheoriesareinvolvedintheconceptofcorotationalrates.Thematerialderivativeofstresswasnotobjectiveunderfinitedeformation .TheJaumannratewasusuallyusedbefo…     

简单剪切有限塑性内时理论分析

在有限塑性内时理论中引入Jaumann率、广义Jaumann率、扶率及Wu率,并以此分析了简单剪切大变形问题．结果验证了简单剪切变形中,采用次弹性或内时刚塑性材料的Jaumann率客观模型,随单调递增的剪切变形剪切应力和法向应力都会出现振荡现象．这说明振荡现象的出现不取决于弹塑性模型,而与选取不同的客观率有很大的关系．同时指出在简单剪切大变形时,法向应力并不为零．     

Existence of solutions to differential inclusions in Banach spaces

I.IntroductionOwingtothefactthatthesystemwithwhicheconomics,biologyandsoonaredefinitelyconcernedtohaveuncertainty,includingthatcausedbyrestrictiononknowledge.asformathematicaltreatment,generallytheycanonlybedescribedbymeansofdifferentialinclusionsinsteadofdifferentialequations.Itiswell-knownthatthederivativex')ofasolutionx.)tothedifferentialequationx'(t)=f(t,x(t))inheritsthereqularityproperitiesofthemapfandthefunctionx(').Thisisnolongerthecasewithdifferentialinclusionsandisoneofthereasonswhyt…     

用投影空间重投影重建迭代法重建电弧温度场

本文结合气体温度场的先验知识,研究了基于光束偏转层析技术的投影空间重投影重建迭代法,考查了数据误差、有限观察角和遮挡物对重建精度的影响.作为一个应用实例,诊断了自由电弧等离子体的温度分布.     

猪肝中克伦特罗和沙丁胺醇的毛细管电泳-质谱联用分析

盐酸克仑特罗和沙丁胺醇等均属激动剂类药物,人体的累计摄入量超过一定值或食用了高残留的内脏组织,易出现毒副作用[1],因此许多国家都将其列为违禁药物。近年来一些不法饲养业主受利益驱使,将沙丁胺醇(salbutamol)作为“瘦肉精”的替代品在生猪养殖中非法使用。关于克伦特罗和     

一种扩展的RBAC模型-GDTRBAC模型的设计

在Sandhu等提出的RBAC96模型中RBAC3的基础上，针对其在机构自身组织结构的管理功能和动态授权方面的不足进行了改进，提出了一种扩展的模型RBAC-GDTRBAC，通过在该模型中引入组、用户授权、有状态任务等概念，增强了RBAC机构管理的能力，增加了对动态授权的支持并能够支持工作的时序要求。