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.     

Exposure dose assessment and discussion on radioisotope production and application

The exposure dose status on radioisotope production and application in China has been assessed in the paper. The average annual occupational exposure dose received by workers in the radioisotope production is about one tenth of the annual dose limit in normal situation. It is less than one twentieth for workers in the radioisotope applications. However, the annual collective dose for the latter is higher than the former by one oder of magnitude due to the larger number of workers in the application field. Although the output of radioisotopes increased doubly in 1980's as compared with 1970's, the increase on the annual collective dose was not obvious. For exposure to the public,¹³¹I for example, the collective dose in the radioisotope production decreased by one to two orders of magnitude and the releasing factor reduced by two orders of magnitude. Therefore, the exposure dose received by workers in radioisotope production and application is lower in normal situation. However, the facts worth paying attention to are that there were many events and accidents which happened in the radioisotope applications, especially at the irradiation facilities. The probability of fatal accident was as high as 10^–3 per irradiator year. In order to improve the radiation safety situation, it is imperative to conduct the safety assessment for irradiation facilities, to enhance management of the radioactive wastes and spent sources and to establish the experience feedback system.     

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.     

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.     

Two Novel Sub-skeleton Types of ent-Kauranoids from Isodon gesneroides

Two novel ent-kauranoids with new sub-skeleton types, gesneroidins G and H were isolated as white powder from the ether extract of the leaves of Isodon gesneroides through normal phase column chromatography. Their structures were elucidated as 3β,6α,7β-triacetoxyl-15-hydroxyl-14-oxo-ent- 15,16-seco-kaur-11,17-olide and Iα-hydroxyl-3β,6α,7β,11 β-tetraacetoxyl-ent-nor-15,17-kaur-8,16-olide on the basis of the spectral evidences including ID and 2D NMR spectra.     

Alkyl- and aryl-substituted corroles. 4. Solvent effects on the electrochemical and spectral properties of cobalt corroles

Solvent effects on the electrochemistry and spectroscopic properties of alkyl- and aryl-substituted corroles in nonaqueous media are reported. The oxidation and reduction of six compounds containing zero to seven phenyl or substituted phenyl groups on the macrocycle were studied in four different nonaqueous solvents (CH(2)Cl(2), PhCN, THF, and pyridine) containing 0.1 M tetra-n-butylammonium perchlorate. Dimers were formed upon oxidation of all corroles in CH(2)Cl(2), but this was not the case in the other three solvents, where either monomers or dimers were formed upon oxidation depending upon the solvent Gutmann donor number and the number or location of aryl substituents on the macrocycle. The half-wave potentials were analyzed as a function of the number of aryl substituents on the macrocycle as well as the concentration of added pyridine to PhCN solutions of the compound, and these data were combined with data from the spectroelectrochemistry experiments to determine the stoichiometry of the species actually in solution after the first oxidation or first reduction of each compound. The results of these experiments indicate that reduction of the bispyridine adduct (Cor)Co(III)(py)(2) proceeds via the monopyridine complex (Cor)Co(III)(py) to give in each case the unligated cobalt(II) corrole [(Cor)Co(II)](-). In contrast, pyridine remains coordinated after electrooxidation, and the final product was characterized as [(Cor)Co(III)(py)(2)](+).     

流通池光度滴定法应用—络合反应中的质子释放数测定

用具有流通池的分光光度计作测定装置,建立了由平衡移动法测定络合反应中质子释放数的新方法。方法简单、快速,仅用一个标准溶液,适于在变更pH值范围内金属离子不发生水解和没有其他副反应的体系。     

N叉树上的离散时间量子随机行走

通过离散时间量子随机行走的框架,我们研究了在N叉树上的离散时间量子随机行走,该框架不需要硬币空间,仅仅只需要选择一个除了酉性再无其它限制的演化算子,并且包含了使用再生结构的轨道枚举和z变换.作为结果,我们在封闭形式中计算了在根处的振幅的生成函数.