Aerobic oxidation assisted by ligand-free palladium catalysts

Aerobic oxidation of electron-rich benzylic and phenyl allylic alcohols was achieved with high yields with only 0.1 mol.% of Pd(OAc)2 catalyst in the absence of any ligand. This procedure was expected to be valuable for realistic industrial-scale applications from both economic as well as environmental points of view.     

稀土在鼠肝中的物种分布

采用 ICP-MS、微量蛋白层析分离技术 ,研究了长时间、低剂量混合稀土及短时间、高剂量硝酸镧分别对大鼠及小鼠作用后 ,稀土在鼠肝中的代谢累积及其物种分布 .结果表明 ,鼠肝中各稀土含量随给药剂量的增加而增大 ,其累积速度大小顺序为 La>Ce>Nd>Pr;经柱层析分离未得到与稀土特异结合的鼠肝蛋白 ;稀土可与多种鼠肝蛋白 (包括多种重要的酶 )结合 ,在一定条件下 ,稀土与其结合蛋白可发生解离     

可剥离膜去除不锈钢表面铀污染的研究

退役的核设施中不锈钢制件表面附着的放射性污染物 ,必须经去污处理后才能回收利用。铀是核工业中最常见的污染放射性元素 ,而不锈钢是核设施中最常用的耐腐蚀金属材料 ,由于以ＵＯ2 +2 状态存在的铀 (Ⅵ ) ,在空气和自身的辐射作用下 ,将逐渐转变为不同的氧化物。采用酸性去污液对不锈钢表面铀污染进行浸泡和擦试去污的方法 ,可以有效的除去不锈钢表面铀污染[1] 。但因浸泡需大量的去污液 ,随之产生大量的带有放射性的废液 ,对这些废液还必须经进一步的浓缩———固化处理。擦试法虽产生固体废物 ,但去污操作麻烦 ,难以对大批量、形状复杂…     

碱解增敏荧光法测定残留甲萘威

甲萘威在0.01mo1/L KOH溶液中可降解为强荧光产物。十六烷基三甲基溴化铵对其增敏后,荧光强度达到其自身荧光强度的6倍。基于此,建立了对残留甲萘威进行荧光测定的新方法。线性动态范围为2.00~1.70×103μg/L;检出限为0.95μg/L;样品的加标回收率在90.2%~99.9%。本法成功地用于叶菜中残留甲萘威的测定。     

Alkylation of benzene with 1-hexene in acidic ionic liquid systems: Et3NHCl-FeCl3and Et3NHCl-AlCl3ionic liquids

Summary The alkylation of benzene with 1-hexene has been investigated in different triethylamine hydrochloride-ferric chloride (Et₃NHCl-FeCl₃) and triethylamine hydrochloride-aluminium chloride (Et₃NHCl-AlCl₃) ionic liquids. Both high catalyst activity and monoalkylation selectivity were observed for these two type of ionic liquids. Systems prepared by modification with HCl in Et₃NHCl-FeCl₃ionic liquids prove to be very suitable solvents and catalysts for the reaction. When employing Et₃NHCl-AlCl₃ionic liquids as catalysts, the reaction takes place in biphasic mode with facile catalyst separation and catalyst recycling.     

2-乙酰氨基-3-苯基-N-苯基-丙烯酰胺衍生物的电子轰击质谱研究

本文报道了6种新的丙烯酰胺衍生物的EI谱。在精确质量测量和B/E,B~2/E联动扫描亚稳离子测定的基础上,着重讨论了该类化合物的共同质谱特征:如分子离子失去H_2O的成环反应;产物离子的开环反应;分子内的氢重排反应等。同时,利用Hammett方程讨论了化合物中N-苯基端苯环上不同取代基对特定碎片离子强度的影响     

偶合反应化学发光法测定痕量银的研究

本文报道了Ａｇ（Ⅰ）催化ｏ－ｐｈｅｎ和Ｋ４Ｆｅ（ＣＮ）６的配位体取代反应与Ｌｕｍｉｎｏｌ－Ｃｕ（ＣＮ）２－４的化学发光反应偶合测定痕量银的方法．方法的线性浓度范围为１×１０－１１～１×１０－７ｇ／ｍＬＡｇ，检出限为４×１０－１２ｇ／ｍＬＡｇ，用于水样分析，结果较为满意     

Concise Synthesis and Antimicrobial Activities of New Substituted 5‐Isoxazolpenicillins

The synthesis of a series of new 5‐isoxazolpenicillins is described, which were obtained by coupling substituted isoxazoles with 6‐APA. Concise large‐scale synthesis of 3,5‐disubstituted isoxazoles by 1,3‐dipolar cycloaddition using copper(I) as catalyst was also investigated. Representative compounds were assayed for antimicrobial activities, showing satisfactory antimicrobial activities against Gram‐negative bacteria.     

柠檬酸铝/聚丙烯酰胺胶态分散凝胶反应动力学和机理的研究

采用粘度法研究了柠檬酸铝（AlCit)与部分水解取丙烯酰胺（HPAM）胶态分散凝胶体系的反应动力学。结果表明，胶态分散凝胶体系的交联反应是一级反应。并推导出胶态分散凝胶体系的反应动力学方程。