二铬四醋酸基簇合物的定域分子轨道研究

利用ＩＮＤＯ自洽场半经验量子化学计算方法和Ｅｄｍｉｓｔｏｎ－Ｒｕｅｄｅｎｂｅｒｇ定域化方法，分别计算了没Ｃｒ－Ｃｒ键长的气相、固相Ｃｒ２（Ｏ２ＣＣＨ３）４分子和沿Ｃｒ－Ｃｒ方向有Ｈ２Ｏ配体的「Ｃｒ２（ＣＯ３）４（Ｈ２Ｏ２）２」＾４－离子的化学键性质，结果表明，Ｃｒ２（Ｏ２ＣＣＨ３）４在气相中存在ｄ四重键，而在固相中则不存在，揭示了四重键长之间的联系，直接给出Ｃｒ－Ｃｒｄ四重键的量子化学图象，并阐明     

植酸与稀土元素的固态配合物的研究

植酸（PllytiC。Cid）又称肌醇六磷酸酯（myo－iflOSitdhX。hSPhOSPh。ie）（简写为H12lHP］常以钙、镁复盐（菲汀Phntin）形式存在于植物中,尤其在谷类和植物的种子中含量较高［'j．植酸具有惊人的骛合能力,除碱金属外几乎能与所有金属离子生成沉淀,一些高价金属离于甚至在强酸性介质中也可定量沉淀［如Ti、Zr、Hf、Th、Ce（IV）和In、Sc等〕,这些性质已初用于Th'"的定量测定L'和SC'"的分离提取「",Gd'"与植酸的配合物被用作核磁共振成倍（MRI）的对比剂［'j．然而,对有关配合物的固态组成及性质研究尚无文献报道．本文…     

PHOTO-INDUCED DOPED POLYANILINE BY THE VINYLIDENE CHLORIDE AND METHYL ACRYLATE COPOLYMER AS PHOTO ACID GENERATOR

The emeraldine base form of polyaniline (PANI) can be doped by a photo-induceddoping method. In this method a copolymer of vinylidene chloride and methyl acrylate(VCMAC) was used as photo acid generator which can release proton when it is exposedto ultraviolet light (λ= 254 nm). The structure of PANI-VCMAC system before and afterirradiation was characterized by elemental analysis, IR, XPS, and SEM images. Resultsobtained indicate that the photo-induced doping characteristics, such as doping positionand type of charge carriers, are similar to that of PANI doped with HCl. The poor room-temperature conductivity (～10~(-5)S/cm) of PANI-VCMAC system after irradiation maybe due to low doping degree (～pH= 3) and the difference in morphology as compared withPANI-HCl film.     

SYNTHESIS OF ORGANOGERMANE OLIGOMERS VIA LIGAND SUBSTITUTION POLYMERIZATION FROM 1, 4-DIOXANE COMPLEX OF GERMANIUM DICHLORIDE

Some organogermanium oligomers with different side groups were synthesized via li-gand substitution polymerization from 1, 4-dioxane complex of germanium dichloride withdifferent organolithitum compounds. The oligomers were isolated through either precipi-tation from methanol or extraction using toluene with a yield of no less than 50%. Theweiglit average molecular weight (M_w) of the oligomers is ranging from 1.4×10~3 to 5.9×10~3depending on the type and alkyl length of the organolithium compounds used.     

Crystal Structure of (6S,9S,13R,14S)-7,8-Didehydro-3,7-dimethoxy-17-methylmorphinan-4,6-diol

1 INTRODUCTION (9S,13R,14S)-7,8-Didehydro-3,7-dimethoxy-4-hydroxy-17-methylmorphinan-6-one I is an impor- tant natural product that was used to ease pain, decrease blood pressure and diminish inflammation. In order to study the stereochemistry of the reduction of I with potassium boronhydride, the crystal structure of the title compound II was determined by X-ray diffraction method. 2 EXPERIMENTAL 2. 1 Instrument The melting point was measured on a Yanagimoto MP-500 apparatus…     

乙烯-α-烯烃共聚物的结晶性能及其临界序列结晶长度的研究

本文用DSC、WAXD及偏光显微镜(PLM)方法,研究了化学反应法催化剂合成的乙烯-α-烯烃共聚物的结晶性能及其临界序列结晶长度。结果表明,随共聚物中α-烯烃含量增大,共聚物的微晶尺寸、结晶度及熔点均逐渐减小,而晶胞参数增大。变化的辐度戊烯>辛烯。共聚物的临界结晶序列长度(n)和k值均戊烯<辛烯。上述结果表明影响支链进入晶格的主要因素是α-烯烃支链长度和结构。     

丙酮中除虫脲溶液标准物质研制

采用重量-容量法制备丙酮中除虫脲溶液标准物质。准确称量国家二级标准物质除虫脲溶解到色谱纯丙酮中,通过A级容量瓶定容至500 mL,摇匀后分装到2 mL安瓿瓶内共460瓶,每瓶为1 mL,保持低温迅速封口,配制过程中室温保持在(20±2)℃。采用液相色谱法进行均匀性、稳定性检验和定值结果验证。从样品中随机抽取16瓶进行均匀性检验,经F检验表明,在95%的置信区间范围内该标准物质均匀性良好;采用t检验对标准物质稳定性进行检验,标准物质在12月内稳定性良好。对该标准物质的不确定度进行了评定,研制的丙酮中除虫脲溶液标准物质定值结果为100μg/mL,相对扩展不确定度为2%(k=2)。结果表明,该标准物质均匀性与稳定性良好,量值准确,可用于日常分析检测中的方法评价和仪器校准。     

密闭微波辅助萃取当归粉中的阿魏酸

利用密闭微波样品制备系统(具有压力控制部件),对当归中的有效成分阿魏酸的萃取进行研究,比较了密闭微波萃取同超声波萃取和索氏萃取阿魏酸提取率的差异.结果表明:微波萃取与其他两种萃取方法相比,具有速度快和萃取率高的特点.并得到了阿魏酸提取的最佳条件:微波功率为400 W,萃取剂为90%的乙醇(体积分数),固-液比为1∶15,微波辐射为240 s,当归粒径为75μm.     

6-O-Sulfated Modification of Natural Glycoalkaloids Chaconine and Solanine

Introduction Glycoalkaloids(GAS)arepotentiallytoxicsecond aryplantmetabolitesfoundinpotatoes,tomatoesand eggplants[1].Someinvestigationshaveindicatedthat glycoalkaloidsmusthavebeenevolvedinnaturetopro tectplantsagainstbacteria,fungi,insects,andani mals.Th…     

丙烯酸Fe3+型树脂在非水介质中对鞣酸的配位吸附及洗脱性能

将Fe3 载于丙烯酸树脂上,制备了在非水介质中对鞣酸具有良好吸附性能的配位吸附树脂.在甲醇中,树脂对鞣酸的吸附符合Langmuir单分子层吸附模型,静态饱和吸附量为34mg/g,吸附为粒扩散控制过程.动态吸附中,树脂对鞣酸的泄漏吸附量为25mg/g,饱和吸附量32mg/g.采用5%的甲胺乙醇溶液作洗脱剂,洗脱率95%.树脂在吸附及洗脱过程中未见Fe3 脱落.