苯基荧光酮－TritonX－100荧光熄灭法测定微量钼研究

本文用荧光熄灭法研究了苯基荧光酮－ＴｒｉｔｏｎＸ－１００－Ｍｏ（Ⅵ）体系的测定方法及条件。在ｐＨ１．０～３．０的盐酸介质中，Ｍｏ（Ⅵ）检测限为０．２μｇ／２５ｍＬｆｆ在０．２～２．０μｇ／２５ｍＬ范围内具有线性关系。本法灵敏度高，选择性好，用于检测球墨铸铁中的微量钼，结果满意。     

双单体原位接枝插层法制备聚丙烯纳米复合材料的研究Ⅰ.制备、表征及力学性能的研究

用有机插层剂处理蒙脱土原土 ,制得有机蒙脱土 (O MMT) .采用双单体 (马来酸酐和苯乙烯 )原位接枝插层法 ,制备了聚丙烯 蒙脱土纳米复合材料母料 .将母料与聚丙烯基体在双螺杆上共混挤出 ,制得聚丙烯 蒙脱土纳米复合材料 (PP Montmorillonetenanocomposites,PMNC) .这是制备聚合物纳米复合材料的一种新方法 .通过X 射线衍射测试 (XRD)表明 ,有机蒙脱土片层 0 0 1面间距从原土的 1 4 9nm扩大到 2 96nm ,复合材料中蒙脱土片层 0 0 1面间距由有机蒙脱土的 2 96nm扩大到 4 0nm .力学性能测试表明 ,复合材料的力学性能明显优于PP基体 ,在提高材料拉伸强度的同时 ,缺口冲击强度也得到很大的提高 .用扫描电镜 (SEM)对材料的冲击断面形貌进行了研究 ,并从理论上分析了断裂机理 .随着蒙脱土含量的增加 ,冲击断裂形式逐渐从脆性断裂变成韧性断裂     

涂膏热解法制备钛基Sn、Sb氧化物电极

研究了涂膏热解法制备Ti/Sn、Sb氧化物电极的新工艺，考察了SnCl4、SbCl3加入量和烧结温度对电极寿命和析氧电位的影响，并对电极进行了SEM、EDS、XRD测试.结果表明，在涂层厚度相近时，涂膏法制备的电极与热解法相比，具有表面氧化物分布均匀和TiO2不易裸露的优点，从而提高了析氧电位，延长了电极寿命，使电极具有很高的电催化活性和电化学稳定性.     

α-四(烷基苯氧基)酞菁配合物的合成与表征

以邻苯二甲酸酐为原料，经硝化、氨化、亲核取代和金属离子模扳等多步反应合成了两个系列共5个叔丁基取代苯氧基金属酞菁配合物，产物经元素分析，IR表征，测定了目标配合物的紫外可见吸收光谱、荧光光谱及在有机溶剂中的溶解性。结果发现：与无取代金属酞菁配合物相比，Q带最大吸收光谱波长红移；在710nm波激发下，目标配合物在环已烷等有机溶剂中均有荧光发射(最大发射波长在760nm左右)；在二氯甲烷、氯仿、环已烷、Py、苯、甲苯、乙基环已烷、乙基溶纤剂等中溶解性能良好。     

Synthesis of Related Compounds of Carotenoid

类胡萝卜素是一类奇特的色素，由高等植物和微生物光化学合成，作为防止单线氧通过光敏反应产生危害的必要基团，类胡萝卜素最近受到了关注。类胡萝卜素联于富勒烯上，既可大大增加在可见光区域光诱导电子转移的有效吸收断面，又可抑制富勒烯敏化单线氧的危害能力。合成了类胡萝卜素的相关化合物，报道的某些反应条件先进且简洁。     

8-羟基喹啉钛配合物/甲基铝氧烷催化体系用于苯乙烯的间规聚合

８ 羟基喹啉钛配合物／甲基铝氧烷催化体系用于苯乙烯的间规聚合许学翔周鼐谢光华（中国科学院化学研究所北京１０００８０）关键词８ 羟基喹啉钛配合物，苯乙烯，甲基铝氧烷，间规聚合自日本学者Ｉｓｈｉｈａｒａ［１］发现单茂钛ＣｐＴｉＣｌ３在甲基铝氧烷（Ｍ...     

Direct Electrochemistry of Hemoglobin in Layer-by-layer {PDDA/Hb}_n Films Assembled on Pyrolytic Graphite Electrodes

The principle of alternate adsorption can be used to design and control specific molecular architectures1. Protein-polyion layer-by-layer assembly opens a possibility of organizing proteins with specific molecular architectural plan1 and studying redox proteins with electrochemical methods2. Recently, we reported electrochemistry of layer-by-layer {PSS/Mb}n films grown on PG electrodes1. In this work, layer-by-layer {PDDA/Hb}n films were fabricated on PG electrodes. Electrochemistry and …     

Laurenidificin, a new brominated C15-acetogenin from the marine red alga Laurencia nidifica

<正>A new brominated C_(15)-acetogenin,namely,laurenidificin,was isolated from the marine red alga Laurencia nidifica.Its structure was determined on the basis of spectroscopic methods.     

Matching Realization of Uq（sln＋1） of Higher Rank in the Quantum Weyl Algebra Wq（2n）

In the paper, we further realize the higher rank quantized universal enveloping algebra Uq（sln＋1） as certain quantum differential operators in the quantum Weyl algebra Wq （2n） defined over the quantum divided power algebra Sq（n） of rank n. We give the quantum differential operators realization for both the simple root vectors and the non-simple root vectors of Uq（sln＋1）. The nice behavior of the quantum root vectors formulas under the action of the Lusztig symmetries once again indicates that our realization model is naturally matched.     

Sieving polymer synthesis by reversible addition fragmentation chain transfer polymerization

Replaceable sieving polymers are the fundamental component for high‐resolution nucleic acids separation in CE. The choice of polymer and its physical properties play significant roles in influencing separation performance. Recently, reversible addition fragmentation chain transfer (RAFT) polymerization has been shown to be a versatile polymerization technique capable of yielding well‐defined polymers previously unattainable by conventional free‐radical polymerization. In this study, a high molecular weight poly‐(N,N‐dimethylacrylamide) (PDMA) at 765 000 gmol^?1 with a polydispersity index of 1.55 was successfully synthesized with the use of chain transfer agent—2‐propionic acidyl butyl trithiocarbonate in a multistep sequential RAFT polymerization approach. This study represents the first demonstration of RAFT polymerization for synthesizing polymers with the molecular weight range suitable for high‐resolution DNA separation in sieving electrophoresis. Adjustment of pH in the reaction was found to be crucial for the successful RAFT polymerization of high molecular weight polymer as the buffered condition minimizes the effect of hydrolysis and aminolysis commonly associated with trithiocarbonate chain transfer agents. The separation efficiency of 2‐propionic acidyl butyl trithiocarbonate PDMA was found to have marginally superior separation performance compared to a commercial PDMA formulation, POP?‐CAP, of similar molecular weight range.