表面修饰二氧化锡纳米微晶的制备与表征

制备了硅烷偶联剂KH-570表面修饰的SnO2纳米微晶，通过FT-IR、XPS、TEM和TG-DTA对其结构和表面特性进行表征和研究. FT-IR和XPS分析结果确证了KH-570与SnO2表面是以化学键合或物理吸附方式相结合,粒子表面存在酯基等有机官能团的红外吸收特征；观测到KH-570中Si原子的Si2s和Si2p谱线. TEM分析表明，表面修饰反应增强了SnO2纳米微晶的疏水性和分散性.由XPS和TG的实测数据探讨了纳米粒子具有较低包覆量的可能原因.     

洋葱色素的提取及抗氧化活性的测定

分别用芬顿（Fenton）反应法和1，1-二苯-2-苦肼基（DPPH）法测定了洋葱色素的抗氧化作用。结果表明，洋葱色素对羟自由基和DPPH自由基均有一定的清除作用，其清除率大小依次为42．4％，58．2％。洋葱色素是十分具有开发利用价值的天然色素。     

汞—钯试剂络合物极谱吸附波的研究

在极谱催化波和吸附波方面,国内进行了大量的研究,但汞的络合物吸附波至今未见报道。钯试剂已用于光度法测定钯等。我们在研究该试剂与金属离子络合的极谱行为时发现,在硼砂介质中,试剂与Hg~(2+)可形成电活性络合物并可用于汞的测定。     

碳碳不饱和键氟化加成反应的研究进展

选择性地向有机物中引入氟原子越来越受到重视，近年来通过碳碳不饱和键的 氟化加成来引入氟原子发展迅速。综述了碳碳不饱和键氟化加成反应的研究进展。     

Synthesis of a homotrifunctional conjugation reagent based on maleimide chemistry

A novel homotrifunctional conjugation reagent, 1,3,5-tris-(N-maleimidomethyl)benzene has been synthesized in high yield with minimum purification. The reactivity of this compound was examined by using l-cysteine as a nucleophile.     

New reagent for the preparation of oligonucleotides involving a 5′-thiophosphate or a 5′-phosphate group

We report here a novel, simple reagent enabling the chemical incorporation of a thiophosphate or a phosphate group at the 5′-end of oligonucleotides using very mild basic deprotection conditions. This method can be useful in the case of alkali sensitive modified oligonucleotides. This reagent also gives access to the preparation of bifunctional oligonucleotides with either a thiophosphate group at the 5′-end and a phosphate at the 3′-end, or two thiophosphate groups at both the 5′- and the 3′-ends, or a 5′-thiophosphate group and a 3′-amino-containing linker.     

NMR determination of enantiomeric composition of 1-substituted 3-amino-1,2-dicarba-closo-dodecaboranes using Eu(hfc)3

Experimental conditions for determination of enantiomeric composition of 1-substituted 3-aminocarboranes by ¹H and ¹³C NMR spectroscopy using chiral shift reagent Eu(hfc)₃ have been found.     

Fast and highly selective determination of cyanide with 2,2-dihydroxy-1,3-indanedione

A very simple, accurate, fast, selective and sensitive assay of cyanide based on its reaction with 2,2-dihydroxy-l,3-indanedione at basic pH is proposed. As little as 0.01 μg ml⁻¹ of cyanide can be determined. The molar absorptivity may reach 5.1–8.0×10⁴ l mol⁻¹ cm⁻¹ depending on the reaction conditions. Thus, 1 ml of sample solution is mixed with 500 μl of 5 mg ml⁻¹ solution of 2,2-dihydroxy-1,3-indanedione monohydrate in 2% sodium carbonate. The absorbance of the purple color is measured at 510 nm in 1-cm glass cuvettes, 10–15 min after mixing the reagents. The procedure could also be used to identify free CN⁻ in natural waters and hydrocyanic acid in the environment.     

SYNTHESIS AND PROPERTIES OF SULFONATED POLY（ARYLENE ETHER） CONTAINING TRIPHENYL METHANE MOIETIES FROM ISOCYNATE MASKED BISPHENOL

A novel sulfonated poly（arylene ether） containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by ^1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N＇-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton＇s reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly （MEA） prepared with the asmade film （706 EW, 100 μm dry thickness） shows better cell performance than Nation 115-MEA in the whole current density range.     

手性多噁唑啉的一步合成方法

尽管已报道了多种结构类型的手性单或双噁唑啉, 但手性多噁唑啉的合成及其应用的文献报道比较少. 本工作以多元羧酸为原料, 与手性2-氨基-1-丁醇经一步反应合成了8个手性多噁唑啉, 产率为89%～98%, 其结构经¹ H NMR谱、IR谱、MS谱和元素分析确证.