温度对Al-Zn-In-Sn-Mg阳极性能影响的探讨

对Al 5Zn 0 .0 5In 0 .1Sn 1Mg合金牺牲阳极进行 5 10℃× 10h的固溶处理 ,测定了未经固溶处理和经固溶处理的阳极在 2 0℃和 6 5℃ 30 g/L的溶液中的电化学性能 ,并进行交流阻抗测试 .结果表明 :温度升高 ,铝阳极电化学性能和溶解性能变差 ;固溶处理对阳极性能改善有利 ;高温下 ,铝阳极晶粒脱落和析氢自腐蚀更剧烈导致阳极电流效率下降 .     

Research progresses of artificial nucleic acid cleavage agents

Artificial nucleic acid cleavage agents have attracted close attention because they play important roles in biochemistry and molecular biology. According to the cleavage mechanism of nucleic acid, they are divided into three types, namely free radical, phosphodiester bond hydrolysis and elimination cleavage agents. In this review, a series of cleavage agents, including the site- and sequence-specific ones, are illustrated, and some suggestions for the future researches in this field are also put forward.     

南海油田海底输油管线失效牺牲阳极的研究

对南海油田某海底输油管线失效的牺牲阳极进行了电化学性能测试、阳极表面溶解形态分析和扫描电镜及能谱分析，并对其溶解产物作了X－射线衍射分析。分析结果表明，阳极失效的原因是其结构存在缺陷，有严重的晶界偏析，从而导致了晶间腐蚀。     

商周玉琮功用浅议

在中国古代文化中,玉琮有其特殊的历史地位,散发着浓郁的气息.它在静止状态中凝聚着张力;在祭祀的烟火缭绕中,它当然又能造成一种静穆和神秘的气氛.     

论清代宗族法三位一体的社会控制功能

清代宗族法代表了中国封建社会宗族法的最高成就。前人对宗族法的研究多囿于宗族内部,未窥全豹。从辩证唯物主义、历史唯物主义的立场出发,自下而上地全面探讨清代宗族法借助家长专制、祭祀之礼、宗族力量实现政治、经济、文化三位一体的全方位的社会控制,有助于了解封建统治延伸到基层社会生活方方面面的历史过程,对于我国社会主义法治理论与实践有着重要的认识和借鉴价值。     

一种含双络合剂的三价铬镀液研究

本文作者研究了以硫氰酸根和甘氨酸为络合剂的三价铬镀液,得到了光亮和均匀的镀层,并讨论了其最适宜的工艺条件和沉积机理.     

Ferric chloride-catalyzed decarboxylative alkylation of β-keto acids with benzylic alcohols

β-Keto acids are unstable to heat,acids,and bases,and have rarely been employed as carbon nucleophiles for the formation of carbon-carbon bonds.In this context,an efficient decarboxylative alkylation reaction of β-keto acids with benzylic alcohols has been developed,for the first time,through sequential cleavage of carbon-oxygen and carbon-carbon bonds.In the presence of 10 mol% of ferric chloride,a range of β-keto acids smoothly undergo decarboxylative alkylation with benzylic alcohols to give structurally diverse unsymmetric ketones in moderate to excellent yields and with extremely high regioselectivity.Preliminary mechanistic studies indicate that the reaction proceeds through an SN1 alkylation followed by decarboxylation.     

镁基脱硫剂与铁水炉外脱硫

介绍几种镁基脱硫剂的制务圾镁基脱硫技术的与应用现状，期望有助于我国镁基脱硫技术的提高。     

磷氮型极压抗磨添加剂性能的研究

合成了磷氮型极压抗磨添加剂亚磷酸二丁酯-马来酸二丁酯-胺衍生物(Ⅰ)和亚磷酸二丁酯-丙烯酸酯-胺衍生物(Ⅱ)。研究表明烷基链较长时油溶性好,用伯胺时极压抗磨性好。经比较,Ⅰ中采用十二胺衍生物(Ⅰ-4)时,其极压抗磨性最好(WSD=0.38mm,P_B=1176N,铜片腐蚀结果为1b),它在基础油(750SN)中最佳用量为2%(wt)。用差热分析、红外光谱和俄歇尔电子能谱初步研究表明:磷氮剂(Ⅰ-4)的作用机理是在摩擦表面形成一种含有磷酸铁的化学保护膜。