A New Synthetic Approach to Elvucitabine

A new synthetic approach to elvucitabine started from L-xylose via the reactions of 10 steps in an overall yield of 20% was developed. The key steps included trimethylsilyl trifluoromethanesulfonate(TMSOTf)-mediated stereocontrolled β-glycosidation and exquisite choice of chloroacetyl group for the protection of hydroxyl groups as well as the corresponding deprotection under notably mild conditions. The structure of elvucitabine, in particular, the stereochemistry thereof, was unambiguously determined by comparison of the physical properties, such as ¹H NMR data and the specific rotation, of the synthesized sample with those reported.     

我国元素病因学研究现状及中药微量元素研究的展望

综述了我国地方病元素病因学及临床疾病元素病因学研究取得的成果,包括：我国地方病元素病因和临床疾病元素病因研究,艾滋病防治的研究,并展望了中药微量元素研究的未来,元素平衡食疗治疗艾滋病的研究,中药元素成分和方剂微量元素成分的研究,有望取得更大的突破性进展。     

N,N′- 双(3-羧基水杨醛叉缩胺乙基)草酰胺均双核铜(Ⅱ),镍(Ⅱ)配合物合成和性能研究

近来发现草酰胺具有多原子成桥功能,Kahn和廖代正等人^[1,2]设计合成一些对称和不对称草酰桥联的双核及多核配合物,并对其性质进行研究,本文报导N,N'-双（3－羧基水杨醛叉缩胺乙基）草酰胺配体及其铜（II）,镍（II）均双核配合物的合成和表征,及铜双核配合物的电化学性能研究。     

Determination of water states and the structural parameters of W/O microemulsions

The states of water in sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane/water reverse(W/O) microemulsions system have been investigated by using Fourier transform infrared spectroscopy(FT-IR) technique. The broad peak obtained for hydroxy(O-H) of water has been resolved by least square curve-fitting. It has been observed that the water solubilized in microemul-sion droplets has four states, i.e. bound water with sulfo-group, free water, bound water with sodium counterion in the water pool of microemulsion droplets and a small amount of trapped water in the palisade layer of microemulsion droplets. The following have also been determined: the aggregation number (n), the radius of the water pool in the microemulsions(rw), the thickness of the bound water with sulfo-group(d1), the thickness of the bound water with sodium counterion(d2), the total thickness of the bound water (d) and the effective area of head groups of AOT(AAOT).     

烷氧基菲咯啉设计合成及其氮磷杂配铜光敏剂的光解水制氢性能

以功能化氮配体为导向,以4,7-二苯基-1,10-菲咯啉为原料,经季铵化、氧化、卤化和醚化合成了一类新型的2,9-二烷氧基-4,7-二苯基-1,10-菲咯啉配体5a~5e。再以Xantphos为膦配体,通过原位配位方法合成一系列氮磷杂配铜光敏剂(Cu PS A~H),在均相光解水制氢体系中研究其光敏活性。制氢结果表明,以2,9-二乙氧基为较佳取代基,Cu PS D的催化产氢总转换数(TON)可达270。在光电物理性能分析中,发现这类杂配铜配合物都有一对相似的氧化还原电位(Eoxd=-0.8 V,Ered=-1.2 V)。具有乙氧取代基的铜配合物CuPSD相对于其他取代基的铜基配合物,荧光最弱,表明乙氧基有助于提高荧光淬灭效率,增强铜光敏剂的光化学转换能力。     

N，N＇-双(3-羧基水杨醛叉缩胺乙基)草酰胺均双核铜(Ⅱ)，镍(Ⅱ)配合物合成和性能研究

The homobinuclear complexes of Cu (Ⅱ) and Ni (Ⅱ) with N, N＇-bis(3-Carboxyl salicyl aminal ethylene) oxalamide were synthesized, and characterized by elemental analysis, IR spectra, Uv-visible spectra, conductometry, thermogravimetry, and magnetic susceptibility measurement, which indicated the complexes own an oxalic amide bridge-linking structure. Room temperature magnetic moment data show that there are antiferromagnetic spin coupling through oxalic amide conjugated double bond, In DMF, the redox half wave potential of Cu (Ⅱ) binuclear complexes have been measured by cyclic voltammetry, which proves that the Cu (Ⅱ) complex has two redox waves.     

表面活性剂和四烷基溴化铵的复配 Ⅲ.四烷基溴化铵碳氢链长对离子型表面活性剂在气/液表面吸附行为的影响

本文考察了四烷基澳化铵(TAAB)碳氢链长对离子型表面活性剂SDS和DTAB在气/液表面吸附行为的影响.实验结果表明,与表面活性剂离子对应的添加剂反离子是影响其水溶液表面活性的主要因素,因而TAAB对SDS表现出明显的效应,对DTAB影响效果则和同浓度的NaBr类似.除了对表面活性离子头基电荷的静电屏蔽外,TAA+的碳氢基团和SD-碳氢链间还可能发生疏水相互作用,但后者受TAA+离子体积制约.TAAB对SDS在气/液表面吸附行为的影响是上述几个因素的综合作用结果.     

活性炭在醋酸水溶液中对醋酸的吸附实验条件探索

通过活性炭在醋酸水溶液中对醋酸的吸附实验 ,确定合适的醋酸水溶液浓度范围和振荡时间等实验条件 ,该实验条件随实验温度变化而不同。用SA310 0表面积分析仪测定活性炭的比表面积 ,并与该方法测定的活性炭比表面积数值进行比较 ,分析了该实验方法产生误差的原因     

电化学生物传感器在环境监测中的应用及发展前景

简要介绍了电化学生物传感器的工作原理,重点论述了电化学生物传感器在环境监测领域的应用及其研究进展,主要包括水环境污染物和大气污染物的监测,以及农药残留的监测等.同时,对电化学生物传感器的发展方向及前景进行了展望.     

溶胶凝胶辅助水热可控合成ZnO不同形貌分级结构光催化剂

以Zn(NO₃)₂·6H₂O、柠檬酸和NaOH为原料,采用溶胶凝胶(sol-gel)辅助水热法,仅通过改变水热时间,就可得到片花、棒花及梭状3种不同形貌ZnO分级结构。利用XRD、SEM、UV-Vis DRS、光致发光光谱(PL)和氮低温吸附-脱附等手段对合成的ZnO样品进行了表征。推测了合成条件下不同形貌ZnO分级结构形成的机理。以活性翠兰(KGL)为模拟印染废水,考察了其光催化活性。结果表明,虽然所合成的不同形貌的ZnO样品在光照120 min后均能使KGL降解78%以上,但其中水热4 h得到的片花状ZnO光催化性能最好,可降解99%的KGL,这与其片花状的形貌、较大的比表面积、较多的表面氧缺陷和极性面有关。