我国大戟二萜酯及其生理活性研究新进展

介绍了我国近１０年来从大戟属植物中发现的二萜酯类新化合物及它们的刺激性，抗癌活性和杀菌作用等生理活性的研究，其中包括５种新发现碳骨架的２０个高氧化型二萜多酯类化合物。     

丙烯酸酯共聚物乳液自交联反应的研究

本文研究了含环氧基的丙烯酸酯四元共聚物乳液交联后的溶胀度、自交联反应及动力学.结果表明:交联共聚物的溶胀度Q随甲基丙烯酸环氧丙酯单体含量的增加而降低,共聚物在受热的情况下,环氧基因在羧基的作用下开环而发生交联反应,产生网状结构.     

层状正极材料LiNi1/6Co1/6Mn2/3O2的制备及电池性能

0引言为解决目前日益严重的汽车尾气排放对城市空气造成污染问题,作为绿色能源的锂离子电池已成为动力电池的首选对象。国际上,高容量、大功率锂离子电池早于1995年已开始研制。1996年,我国天津电源研究所也进行了大容量锂离子蓄电池及电池组的探索[1]。目前,锂离子电池的正极材料是制约其大规模推广应用的关键。现研究的正极材料主要包括具有层状结构的LiCoO2,LiN iO2和LiM nO2及具有尖晶石结构的LiM n2O4等。其中LiC oO2作为目前唯一已经商业化的正极材料具有理论容量高、可循环性能好等优点,但因Co资源的相对缺乏导致其价格高昂。…     

Copper Promoted Au/ZnO-CuO Catalysts for Low Temperature Water-gas Shift Reaction

IntroductionThe water-gas shift(WGS)reaction is an impor-tant step in many important chemical processes[1].Re-cently,the renewed interest in the removal of CO bythe WGS reaction has grown significantly because of theincreasing attention to pure hydrogen p…     

Pb2＋在液/液界面迁移的电化学研究及其应用

用循环伏安法研究了双硫腙络合推动Pb^2＋在水/乙酰丙酮界面迁移的伏安过程. 实验证明, 该过程是受扩散控制的不可逆过程, Pb^2＋由水相转移到有机相中, 与双硫腙形成络合物Pb(DzH)₂. Pb^2＋的峰电位在－0.3 V处, 并且在5× 10^－6～0.1 mol•L^－1范围内与峰电流成正比. 这一方法为工业废水中铅的在线、现场测定提供了可靠、灵敏的检测方法.     

A-P-S组合策略的多重绩效及其“褪色”效应分析

为了降低城市交通拥堵及空气污染程度,本文在现有研究的基础上引入罚款政策,利用系统动力学方法原理构建了机动车污染物减排管控模型。通过仿真和比较分析来探索空气污染收费(Air pollution charging fee,简称APCF)、罚款(penalty)和补贴(subsidy)政策(简称A-P-S策略)的作用效果。研究结果表明:一方面,组合策略具有多重绩效,不但能够降低污染损失(经济-环境效益)、死亡人口的生命价值(社会-经济效益)、交通拥堵程度(社会效益)和机动车污染物总量(环境效益),而且能大大改善环境生态承载力(环境效益)和机动车非法出行增长量(社会安全绩效);另一方面,政策在实施过程中也会遇到一定的局限性,如初期的滞后性,后期的“褪色”效应和“反弹”效应,因此,从长期来看,需要及时调整组合方案。最后,根据仿真结果提出了相应的政策建议,进而为城市交通和环保等相关部门提供决策参考。     

ISOLATION,CHARACTERIZATION AND EXPRESSION OF THE COMPLEMENTARY DNA FOR HUMAN TUMOR NECROSIS FACTOR (TNF-α)

A cDNA for human TNF-α (615bp) was isolated by means of polymerase chain reaction (PCR) using first strand cDNA from PMA-induced HL-60 cells as template. The result from sequencing the 615 bp cDNA fragment indicated that it corresponded to the entire sequence of mature human TNF coding region. Direct expression of mature human TNF was achieved using a plasmid pHT-1 constructed by ligation of the cDNA and a synthetic DNA. The IPTG-induced bacterial product (hTNF) showed cytotoxicity to mouse L-929 cells. The TNF activity was further identified by neutralization of a specific monoclonal antibody against human TNF-α. Approximately 80,000 units of activity were detected per ml of culture at A600=2.     

Y2O3涂层负载Pd整体式催化剂的制备和催化性能

以Y(NO3)3为前驱体制备了Y2O3涂层的堇青石蜂窝陶瓷载体.扫描电子显微镜、X射线能谱和超声波振荡等表征结果表明,Y2O3涂层不但具有良好的抗振荡性和粘结强度,而且具有很强的吸附催化剂活性组分(H2PdCl4)的能力,适合制备负载型Pd催化剂.以甲苯和乙酸乙酯完全燃烧为模型反应考察了催化剂的活性,发现以Y2O3涂层堇青石蜂窝陶瓷为载体的整体式Pd/Y2O3催化剂具有良好的催化活性和热稳定性,甲苯和乙酸乙酯催化燃烧的T99分别为210和300℃;催化剂经900℃焙烧4 h后,T99仅提高20℃,表明催化剂具有很高的热稳定性.催化剂的X射线衍射、拉曼光谱和程序升温还原结果表明,Pd/Y2O3催化剂经低温焙烧时,Y2O3和PdO均高度分散在堇青石蜂窝陶瓷的表面,而高温焙烧使催化剂活性组分PdO晶粒增大,从而导致催化剂活性下降.     

Fe(OH)2悬浮液在EDTA作用下氧气氧化生成δ-FeOOH的机理研究

At room temperature and in the presence of trace EDTA, the formation of δ-FeOOH was studied by the rapid oxidation of Fe(OH)2 suspension with O2. The structural and morphological changes were characterized by various techniques such as XRD, FTIR and TEM. γ-FeOOH and (δ-FeOOH) formed simutaneously in the early period of oxidation. But as the rate of mass transfer was in equilibrium, trace (γ-FeOOH) vanished gradually. Accordingly, pure phase δ-FeOOH was obtained. At the same time, critical amount ratio K of EDTA to Fe2+ was verified. The experiments show that the reactivity, rate of the oxidizing agent and pH of the initial medium were important factors for the formation of pure phase (δ-FeOOH). Under the auxiliary effect of EDTA, the reactivity of O2 was nearly improved to that of H2O2. And the process of the oxidation that Fe(OH)2 suspension was oxidized by O2 under that condition was discussed.     

一个新颖的三维异核锑(Ⅲ)-镨(Ⅲ)配合物[Sb2-μ4-(EDTA)2Pr(H2O)5]NO3·4H2O的合成、晶体结构及热分解研究

合成了锑-镨与乙二胺四乙酸形成的新颖三维配合物[Sb2-μ4-(EDTA)2Pr(H2O)5]NO3·4H2O,用元素分析、红外光谱、热分析及X射线单晶衍射法等进行了组成和结构表征.结果表明该配合物属正交晶系,空间群Pnn2;晶胞参数:a=1.07031(2)nm,b=2.30805(4)nm,c=0.72343(2)nm,V=1.78711(7)nm3,Z=2,Dc=2.202g/cm3,F(000)=1164,μ=2.955mm-1,GOF=1.000,最终偏离因子R1=0.0203,wR2=0.0545[I>2σ(Ⅰ)].在标题化合物中,每个镨(Ⅲ)离子的配位数为9,与五个水分子中的五个氧原子和四个羧基氧原子配位,形成三帽三角棱柱空间配位多面体.锑(Ⅲ)与EDTA离子中的四个氧原子和两个氮原子配位,在赤道平面上有一孤对电子.同时讨论了配合物的热分解过程.