Novel Method of Preparation of Monolithic Columns for Fast Separation by γ-Ray Irradiation

A porous monolithic sol-gel column with the solution of methacryloxypropyltrimethoxysilane in toluene with an acid catalyst was prepared in the presence and absence of sodium dodecyl sulfate. In situ polymerization was carried out byγ-ray irradiation within the capillary. Theγ-radiation-initiated synthesis could generate radicals directly on the monomer avoiding use of any initiator. The chromatographic behavior of the capillary monolithic columns were studied in the modes of CEC, p-CEC and low pressure-driven separation, all the tests exhibited reversed-phase character. It provided a viable alternative to either thermally initiated or photo polymerization method for the preparation of monolithic columns.     

交流示波极谱滴定法测定氧氟沙星

１引言氧氟沙星（Ｏｆｌｏｘａｃｉｎ，ＯＦＬＸ）为新一代喹喏酮类抗菌药，其含量测定，文献报道可用分光光度法、ＨＰＬＣ、毛细管电泳法、离子选择电极法等。本文详细研究了交流示波极谱滴定法测定ＯＲＬＸ的实验条件，并用以测定其注射液和片剂的含量。２实验部分２．１仪器与试剂交流示波极谱仪，按文献（高鸿，示波极谱滴定，南京：江苏科技出版社，１９８５：１７）组装，ＵＶ－７５４分光光度计（上海第三分析仪器厂），ＯＦＬＸ注射液、片剂、化学对照品（北京制药厂）。容量仪器均经过校正，所用试剂四苯硼钠、硫酸亚铊及ＨＡｃ－…     

乙醇对合成醇用Cu-Co-Fe催化剂的修饰效应

乙醇对合成醇用Ｃｕ┐Ｃｏ┐Ｆｅ催化剂的修饰效应徐杰王向宇杜宝石（郑州大学化学系，郑州４５００５２）辛勤李灿（中国科学院大连化学物理研究所，大连１１６０２３）关键词铜，钴，铁，合成醇，乙醇，修饰作用分类号Ｏ６４３／Ｏ６４７自７０年代以来，已对多种ＣＯ加...     

The Purification of Glucose Type Glycosyl Nitrate and the Synthesis of Spacer—armed N—Acetyllactosamines and Their Dimers

Our previous paper1,2reported the results of selective synthesis of mannose type glycosides and their dimers in our attempt to synthesize derivatives of N-acetyllacto- samine, which could have potential activity of anti-metastasis3. Further studies on the glycosylation of the accepters exploiting glycosyl nitrate instead of the acetate as donor showed interesting chemoselectivity between the two kinds of donor, namely, the glucose type and the mannose type. The reactivity difference of the t…     

Microelectrode Studies on the Pitting Corrosion Process of Stainless Steel

应用微电极法研究不锈钢点腐蚀发生发展过程，首次获得不锈钢夹杂物缺陷在阳极活化电位的活性溶解信息和点腐蚀发展过程蚀点生长和消止两个相互竞争、不断发展的动态行为，深化对夹杂物缺陷诱导点腐蚀的发生及点腐蚀发展过程机理的认识。实验表明，应用微电极技术研究点腐蚀过程可具有若干明显特点：ａ．由于界面双层电容和背景电流的大幅度降低，有利于检测点腐蚀发生和发展过程快速、信号微弱；ｂ．可考察夹杂物缺陷的电化学活性及其诱导点腐蚀成核的重要作用；ｃ．可研究单孔点腐蚀发展的动态行为及影响因素。     

硼烷缺电子多中心桥键的H-F力研究

Hellmann-Feynman静电力表现了分子中电荷分布及对各原子核的作用。H-F力的方向性可描述电子电荷的数量和位置,具有定量、形象和直观的特点,已在弯键的研究中显示出来。这一方法尚可用于多中心缺电子桥键的研究。 1 理论与方法 按LCAO-MO理论对H-F力进行分解,除有重叠力、极化力和屏蔽力外,还有一     

Synthesis of Novel Benzoylphenylurea Chitin Inhibitors From Chlorothalonil(Ⅱ)

IntroductionThe insecticidal activity of benzoylphenylurea( BPU ) analogues,discovered in the early1 970′s[1_ 4] ,is connected with the process ofmoult-ing and appears to affect the chitin synthesis of in-sects. The benzoylphenylurea class of insectgrowth regulators( IGRs) ,interfere with chitinsynthesis in target pests,causing death or abortivedevelopment and are considered to be the fourthgeneration of insecticides or novel materials for in-sect control.Benzoylphenylurea type insecticides…     

镨、钕、钇、甘氨酸三元配合物的晶体结构

在水溶液中培养了镨、钕、钇与甘氨酸形成的三元配合物。元素分析和热分析表明，该配合物可用Ｐｒ_ｘＮｄ_ｙＹ_ｚ（Ｇｌｙ）_６（Ｈ_２Ｏ）_４（ＣｌＯ_４）_６·５Ｈ_２Ｏ（Ｘ＋ｙ＋ｚ＝２）表示其分子式。Ｘ射线衍射方法测定了其单晶结构，结果表明，该晶体属三斜晶系，空间群Ｐ１，化学式Ｐｒ_（０．７７５）Ｎｄ_（０．７００）Ｙ_（０．５２５）Ｃｌ_６Ｏ_（４５）Ｎ_６Ｃ_（１２）Ｈ_（４８），Ｍ_ｒ＝１４６６．０９，晶胞参数如下：ａ＝１１．５６４（１），ｂ＝１４．１１８（３），ｃ＝１５．６６８（２）Ａ，α＝９６．９９（１），β＝１０２．７２（１），γ＝１０５．３３（１）°，晶胞体积Ｖ＝２３６２（１）Ａ~３，Ｚ＝２，Ｄ_ｃ＝２．０６０ｇ／ｃｍ~３，结构偏离因子Ｒ＝０．０３２，Ｒ_ｗ＝０．０４８。晶胞中存在两个络合单元，每个单元可用Ｍ_１Ｍ２（Ｇｌｙ）_６（ＣｌＯ_４）_６（Ｈ_２Ｏ）_４．５Ｈ_２Ｏ表示，Ｍ_１＝０．４Ｐｒ＋０．３７５Ｎｄ＋０．２２５Ｙ，Ｍ２＝０．３７５Ｐｒ＋０．３２５Ｎｄ＋０．３０Ｙ。三种稀土元素按一定比例统计性地占有两个格位。羧基以桥式联结金属离子，形成一维链式聚合物结构。在络合单元中，一个稀土离子是９配位，其配位多面体为畸变?     

2020 Roadmap on two-dimensional nanomaterials for environmental catalysis

This roadmap demonstrates a series of two-dimensional nanomaterials, such as graphene, black phosphorus, oxides, layered double hydroxides, chalcogenides, bismuth-based layered compounds, MXenes, metal organic frameworks, covalent organic frameworks, and others, for environmental catalysis.     

Recyclable self-assembly-supported catalytic system for orthoalkylation

[reaction: see text] A new recyclable supported catalyst system for orthoalkylation was devised using a self-assembly consisting of the barbiturate and 2,4,6-triaminopyrimidine H-bonding motifs. At high temperature, the system is completely homogeneous so as to give an efficient catalytic activity, while it is heterogenized at room temperature to form an insoluble solid phase for the easy recovery of the catalyst after the reaction.