液膜法分离钒(Ⅳ)的研究

本文用P204-兰113A-煤油组成的滤膜体系处理钒(Ⅳ)的溶液,并考察了表面活性剂、载体、外相pH值、内相酸度、起始钒(Ⅳ)浓度以及乳水比等因素对分离的影响。     

Zr（Ⅳ）／PVA功能膜的膜催化酯化反应研究

在催化与渗透汽化分离技术相偶合的渗透汽化型膜反应器中，研究了羧酸酯的液相合成反应．实验中制备了两类具有强酸催化活性的ｚｒ（Ⅳ）／ＰＶＡ（聚乙烯醇）功能膜，采用管式膜方式，以乙酸正丁酯的合成反应为探针，对这类新型的催化反应技术在催化活性、分离性能以及分离对反应转化的影响等方面进行了探索性研究。从得到的结果看，膜催化酯化反应过程的反应条件和缓，转化率可达到９８％，反应的选择性为１００％．     

某些分子光谱分析法测定核酸的进展

对近年来利用分光光度法、荧光法和共振光散射法定量测定核酸的现状进行了评述，表中列出了重要的反应体系及分析特征，引用文献77篇。     

LBL分子沉积法制备葡萄糖氧化酶电极

采用以静电力为主的逐层分子交替沉积技术制备葡萄糖氧化酶（GOD）电极.通过带有正电荷的聚二甲基二烯丙基铵盐酸盐（PDDA）和带有负电荷的GOD交替沉积在修饰有3-巯基-1-丙基磺酸钠（MPS）的金电极表面.以甲酸二茂铁为电子媒介体,用循环伏安法检测GOD电极对葡萄糖的响应.结果表明,当GOD电极组装层数小于4时,电流响应随着层数的增加而增大,超过4层时电流响应减小.其中4层GOD修饰电极的线性范围为0.55～6.63 mmol•L－1,当pH为7.0时,响应最大.同时电极的检测重现性能良好,相对标准偏差为2.4％.     

Cure reaction and phase behavior of liquid crystalline epoxides-anhydride systems

A series of novel liquid crystalline epoxides with lateral substituents were cured with anhydrides and the cure kinetics was investigated by non-isothermal DSC technique. The results showed that the lengths of lateral substituents have great effect on the value of Ea. The curing reaction became less active, when the liquid crystalline epoxides have long lateral substituents and were controlled by diffusion at the late stage of cure. A nematic structure was observed by POM and XRD.     

无焰燃烧烟密度标准物质的研制

介绍无焰燃烧烟密度标准物质的研制方法。选用合适的α-纤维素作为原材料,经打浆造纸后,作为标准物质候选物,经均匀性检验和稳定性考察合格后,对标准物质进行定值。在无焰燃烧条件下烟密度标准物质的标准值为175,扩展不确定度为8;校正烟密度标准物质的标准值为166,扩展不确定度为8。     

Lignanoids and Diterpenoids from Callicarpa furfuraceae

The three new lignanoids 1 – 3 and the five new phyllocladane diterpenoids 7 – 11 were isolated from the leaves of Callicarpa furfuraceae, together with two known lignanoids, lariciresinol ( 4 ) and (+)‐sesamin ( 5 ), and five known diterpenoids, 17‐norphyllocladane‐3,16‐dion ( 6 ), calliterpenone ( 12 ), calliterpenone 17‐acetate ( 13 ), (3β,16α)‐phyllocladane‐3,16,17‐triol ( 14 ), and (3β,16α)‐phyllocladane‐3,16,17‐triol 17‐acetate ( 15 ). Their structures were established by spectral‐data interpretation.     

pH值对人参皂苷溶出影响规律的液质联用研究

采用液质联用(HPLC-ESI-MSn)技术, 对不同pH值(2.4~11.2)条件下人参皂苷的溶出变化规律进行了系统研究, 并提出了不同人参皂苷化合物的特征质谱裂解规律. 实验结果表明, 中性及碱性溶液对人参皂苷的溶出影响不大, 仅仅在溶出总量上有所差别; 而酸性是影响人参皂苷溶出的一个主要因素, 随着水溶液酸性的增强(pH<4), 人参皂苷溶出的种类明显减少, 表明较强酸性条件下人参皂苷的溶出受到了抑制.     

Poly(choloyl)-based amphiphiles as pore-forming agents: transport-active monomers by design

This paper describes the design and synthesis of a family of pore-forming amphiphiles. Two of these amphiphiles, which are derived from cholic acid, lysine, and p-phenylenediamine, can produce pores in lipid bilayers as individual molecules. In sharp contrast, analogous amphiphiles that do not contain a rigid 1,4-phenylenediamide moiety favor the formation of dimer-based pores. Kinetic evidence in support of monomer- and dimer-based pores has been obtained from Na+ transport measurements across bilayers made from 1-palmitoyl-2-oleoyl-2-sn-glycero-3-phosphocholine (POPC). Structure-activity studies that have been carried out with pore-forming, dimer-based amphiphiles have also revealed a significant activity dependence on their overall compactness. The practical potential of pore-forming amphiphiles with controllable supramolecular properties is briefly discussed.     

First total synthesis of a GPI-anchored peptide

A GPI-anchored dipeptide of sperm CD52 antigen was prepared through a convergent synthesis. First, the dipeptide with its C-terminus free and the GPI with its nonreducing end phosphoethanolamine bearing a free amino group were synthesized separately. Then, the two building blocks were coupled with use of EDC/HOBt as the condensation reagent. Finally, the GPI-anchored peptide was deprotected to give the target molecule 1.