λ噬菌体溶源/裂解转换调控与定态熵

被λ噬菌体感染的大肠杆菌是研究生物基因调控网络的重要模板之一. 根据该调控系统操纵子与调控蛋白相互作用特点, 利用热力学配分函数描述调控蛋白与操纵子的结合概率, 在给出该调控系统的动力学分岔的基础上, 计算系统各定态的热力学熵. 结果显示, 溶源态和裂解态较鞍点和分岔点具有更低的熵值, 且溶源态的熵最低, 说明处于溶源态的系统具有更高的生物序.     

加权Herz型Hardy空间上的Littlewood-Paley g*λ函数

讨论了在q=2的情形下,Littlewood-Paley gλ*函数在加权Herz型Hardy空间中的有界性,即当0相似文献   

双菱体λ/4消色差相位延迟器的设计

根据菲涅尔全内反射相变理论,给出了双菱体λ/4消色差器的结构设计、性能分析和测量方法.由有效通光孔径和光线追迹设计出BK7玻璃在波长532 nm时相位延迟λ/4的双菱体的结构,用作532 nm至1 064 nm波长范围的标准λ/4相位延迟器.理论分析了入射角变化和波长变化对双菱体相位延迟的影响,当入射角变化限制在±4.3°以内时,其影响得到补偿;波长从532 nm到1 064 nm产生的误差为－0.65°.采用椭偏法中的消光技术,分别实测了双菱体在532 nm和1 064 nm波长下的相位延迟为：90.08±0.14°和88.99±0.1°,可知两不同波长产生的相位延迟误差为－1.09°.     

Generalized R-KKM theorems in topological space and their applications

In this paper, we introduce generalized R-KKM mapping and discuss some new generalized R-KKM theorem under the nonconvexity setting of topological space. As applications, some new minimax inequalities, saddle point theorem are proved in topological space. Our theorems unified and extend many known results in recent literature.     

A convenient approach to λ-phosphinines via interaction of phosphorylated 3-pyrrolidinocrotonitrile with 2-bromoacetophenones

The alkylation of 2-(diphenylphosphino)-3-pyrrolidin-1-ylbut-2-enenitrile with a set of bromoacetophenones has been studied. Cyclization of the phosphonium salts into 6-cyano-3-hydroxy-3-aryl-1,1-diphenyl-5-pyrrolidin-1-yl-1,2,3,4-tetrahydrophosphininium bromides under heating in the presence of catalytic amount of a base is discussed. Starting both from the acyclic and the cyclic phosphonium salts, new types of λ⁵-phosphinines have been synthesized.     

[2,2,2-TRIFLUOR-1-(2-HYDROXYPHENYL)ETHYL]-PHOSPHONSÄURE: MOLEKÜLSTRUKTUR VON [2,2,2-TRIFLUOR-1-(2-HYDROXYPHENYL)-ETHYL]DIMETHYLPHOSPHONAT

Abstract

The interaction of trimethylphosphite (1) and 2-trifluoroacetylphenol (2) yielded 4,5-benzo-2,2,2-trimethoxy-3-trifluoromethyl-1,2λ⁵[sgrave]⁵-oxaphosphol (3) and trimethylphosphate but not the expected 3-hydroxy derivative. Hydrolysis of compound 3 furnished the respective acyclic dimethylphosphonate 4 which was converted into the bis(trimethylsilyl)ester 5 and finally into the free phosphonic acid 6. O-trimethylsilylated compound 8 added to tris(trimethylsilyl)phospite (7) furnishing phosphonate 9 without abstracting the [sgrave]-oxygen. The molecular structure of 4 exhibited a somewhat distorted tetrahedral arrangement of substituents around phosphorus. An intermolecular hydrogen bridge O—H… O[dbnd]P was observed (O…O = 266.7 pm).     

超立方体上的多元线性回归模型的最优设计

对n维超立方体上的多元线性回归模型采用2n个顶点进行均匀测度设计,证明了该设计在Iλ最优准则及D、A最优准则下都是最优设计,并给出了n=2,3时的最小二乘估计.     

Synthesis of phosphanaphthalenes and nido-carborane fused six-membered phosphacycles

A simple method to synthesize luminescent λ⁵-phosphanaphthalenes and zwitterionic nido-carborane fused six-membered phosphacycles was developed from the reaction of ortho-phosphinobenzoaldehydes or ortho-phosphinocarboranylaldehydes with an electron-deficient alkyne,respectively.Similar results were obtained with the imino analogues.