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反应型三元铽配合物的合成及发光性能研究

中国稀土学报 2004年第2期22卷 196-200页

作者：郭栋才舒万艮周悦刘又年中南大学化学化工学院湖南长沙410083 湖南大学化学化工学院湖南长沙410082

以邻菲咯啉为第一配体,顺丁烯二酸酐、丙烯腈、十一烯酸、油酸、亚油酸为活性第二配体,合成了5种新的反应型三元铽配合物。通过元素分析,EDTA配位滴定分析,红外、紫外、荧光光谱分析,对标题配合物的组成、结构进行了表征,并研究了它们... 详细信息

以邻菲咯啉为第一配体,顺丁烯二酸酐、丙烯腈、十一烯酸、油酸、亚油酸为活性第二配体,合成了5种新的反应型三元铽配合物。通过元素分析,EDTA配位滴定分析,红外、紫外、荧光光谱分析,对标题配合物的组成、结构进行了表征,并研究了它们的发光性能。结果表明,五种新的反应型三元配合物与相应的二元配合物相比发光强度大大提高,且配合物中引入了能与其它单体共聚的活性第二配体,为合成具有优异发光性能的键合型稀土高分子功能材料提供了一条新的途径。

关键词：无机化学邻菲咯啉反应型三元配合物发光稀土

Formation and evolution mechanisms of large-clusters during rapid solidification process of liquid metal Al

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Science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 101-112页

作者： LIU Rangsu, DONG Kejun, LIU Fengxiang, ZHENG Caixing, LIU Hairong & LI Jiyong Department of Applied Physics, hunan university, changsha 410082. China {2. of Materials Science and engineering, hunan university, changsha 410082. China {2. of chemistry and chemical engineering, hunan university, changsha 410082. China 1. Department of Applied Physics Human University 410082 Changsha China 2. college of Materials Science and engineering Hunan University 410082 Changsha China 3. college of chemistry and {2. engineering Hunan University 410082 Changsha China

A molecular dynamics simulation study has been performed for the formation and evolution characteristics of nano-clusters in a large-scale system consisting of 400000 atoms of liquid metal Al. The center-atom method combined with pair-bond analysis technique and cluster-type index method (CTIM) has been applied here to describe the structural configurations of various basic clusters. It is demonstrated that both the 1551 bond-type and the icosahedral cluster (12.0 12.0) constructed by 1551 bond-types are dominant among all the bond-types and cluster-types, respectively, in the system and play a critical role in the microstructure transitions of liquid metal Al. The nano-clusters (containing up to 150 atoms) are formed by the combination of some middle and small clusters with distinctly different sizes, through mutual competition by unceasing annex and evolution in a seesaw manner (in turn of obtaining and losing),which do not occur as the multi-shell structures accumulated with an atom as the center and the surrounding atoms are arranged according to a certain rule. This is the essential distinction of nano-cluster in liquid metal from those obtained by gaseous deposition, ionic spray methods, and so on. Though the nano-clusters differ from each other in shape and size, all of them possess protruding corners that could become the starting points of various dendrite structures in the solidification processes of liquid metals.

关键词： liquid metal, solidification process, large-cluster configuration, evolution mechanism, computer simulation.

Silylated and acetylated β-cyclodextrins for gas chromatographic stationary phases

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Journal of Central South university of Technology 2001年第4期8卷 239-243页

作者： TANG Ke wen 1,2.,YI Jian ming 2.ZHOU Chun shan 1,ZHONG Shi an 1 (1. college of chemistry and {2. engineering, Central South university, changsha 410083, China 2. college of chemistry and chemical engineering, Yueyang Normal university 1. college of chemistry and {2. engineering Central South University 410083 Changsha China 2. college of chemistry and chemical engineering Yueyang Normal University 414000 Yueyang China

Two new chiral stationary phases, 2.3 di O acetyl 6 O trimethylsilyl β cyclodextrin (DATBCD) and 2.6 di O trimethylsilyl 3 O acetyl β cyclodextrin(DTABCD), were synthesized, their structures were identified by means of infrared and NMR spectra. Capillary columns were coated with the two stationary phases by dynamic method. The chromatographic properties, and enantiomers separation, such as ketone, esters, alcohols and olefines, were investigated on the silylated and acetylated β cyclodextrin stationary phases. The experimental results show that the silylated and acetylated β cyclodextrins are suitable to be used as capillary gas chromatographic stationary phases, the relative polarity of DATBCD and DTABCD stationary phases is respectively 4143 and 392., the column efficiencies are respectively 3084 and 4198, and DATBCD is of stronger enantioselectivity than DTABCD, capacity factor of the first eluted enantiomer ( k 1) and separation factor(α)of α phenylethanol on DATBCD stationary phase are respectively 8.2. and 1.019.

关键词： capillary gas chromatography silylated and acetylated β-cyclodextrins enantiomeric separation

Effect of static magnetic field on activity of immobilized α-amylase

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Chinese Science Bulletin 1997年第2期42卷 127-130页

作者： YAN Liushui, ZHU Yuanbao, HE-Shuang’e and CAO Zhixiang1 Department of chemical engineering, Nanchang Institute of Aeronautical Technology, Nanchang 330034, China 2. Department of {2. and chemical engineering, hunan university, changsha 410082. China Department of chemical engineering Nanchang Institute of Aenwututical Techndogy Nanchang China Department of chemistry and chemical {2. Hunan University Changsha China

BIOLOGICAL effect of magnetic field is one of the three major subjects of contemporary biomagnetism, and is also the basis of applied biomagnetism. In order to explore magnetic biological effects, the influence of various sorts of magnetic field on many living systems as well as their different constructural levels has been extensively studied. However, only a few studies with in vitro enzyme have been reported, and few researches concerning the influence of magnetic field on immobilized enzyme reactions have been published. This note describes

关键词： static magnetic field immobilized α-amylase enzyme activity oscillatory behaviour.

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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Science China chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2. ZHANG GuoLi2. HUANG KeLong2. LI Yuanjian3 & YI JianMin1,2.1 Department of chemistry and chemical {2., hunan Institute of Science and Technology, Yueyang 414000, China 2.college of chemistry and chemical {2., Central South university, changsha 410083, China 3 college of Pharmaceutical Science, Central South university, changsha 410078, China Department of chemistry and chemical {2. Hunan Institute of Science and TechnologyYueyang 414000China college of chemistry and {2. engineering Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2.dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 2..6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Synthesis and purification of trialkyl compounds of gallium and indium

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Rare Metals 2002年第1期21卷 1-6页

作者： SHU Wangen, ZHOU Zhongcheng and LI Xiong chemistry and chemical {2. college, Central South university, changsha 410083, China chemistry and chemistry {2. college Central South University Changsha 410083 chemistry and chemical {2. college Central South University Changsha 410083

The The research progress in trialkyl compounds of gallium andindium was discussed from two aspect, one was the chemical synthesisof the compounds and the other was the purification of them. Thereare three synthesis routes be- ing reported in the first aspect, *** route staring form pure metal, the route starting from the puremetal trihalides, and the electrochemical route. In the secondaspect, the purifying methods of decomposition-distillation and zonerefining were reviewed.

关键词： trialkyl compounds gallium nd indium synthesis purification

Preparation of well-defined polystyrene/silica hybrid nanoparticles by ATRP

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Science China chemistry 2008年第1期51卷 51-57页

作者： OU BaoLi1,2.LI DuXin2.1 college of chemistry and {2. engineering,hunan university of Science and Technology,Xiangtan 4112.1, China 2.State Key Laboratory of Powder Metallurgy,Central South university,changsha 410083, China 1. college of chemistry and {2. engineering Hunan University of Science and Technology Xiangtan 411201 China 2. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

Immobilization of the atom transfer radical polymerization (ATRP) macroinitiators at the silica nanoparticle surfaces was achieved through surface modification with excess toluene-2.4-diisocynate (TDI), after which the residual isocyanate groups were converted into ATRP macroinitiators. Structurally well-defined polystyrene chains were grown from the nanoparticle surfaces to yield individual particles composed of a silica core and a well-defined, densely grafted outer polystyrene by ATRP, which was initiated by the as-synthesized silica-based macroinitiator. FTIR, NMR and gel permeation chro-matography (GPC) were used to characterize the polystyrene/silica hybrid particles.

关键词： silica nanoparticles surface modification atom transfer radical polymerization polystyrene hybrid particle

Preparation of polystyrene/silica nanocomposites by radical copolymerization of styrene with silica macromonomer

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Science China chemistry 2007年第3期50卷 385-391页

作者： OU BaoLi1,2.& LI DuXin2.1 college of chemistry and {2. engineering, hunan university of Science and Technology, Xiangtan 4112.1, China 2.State Key Laboratory of Powder Metallurgy, Central South university, changsha 410083, China 1. college of chemistry and {2. engineering Hunan University of Science and Technology Xiangtan 411201 China 2. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

A two-stage process has been developed to generate the silica-based macromonomer through surface-modification of silica with polymerizable vinyl groups. The silica surfaces were treated with excess 2.4-toluene diisocynate (TDI), after which the residual isocyanate groups were converted into polymerizable vinyl groups by reaction with hydroxypropylacrylate (HPA). Thus, polystyrene/silica nanocomposites were prepared by conventional radical copolymerization of styrene with silica macromonomer. The main effecting factors, such as ratios of styrene to the macromonomer, together with polymerization time on the copolymerization were studied in detail. FTIR, DSC and TGA were utilized to characterize the nanocomposites. Experimental results revealed that the silica nanoparticles act as cross-linking points in the polystytene/silica nanocomposites, and the glass transition temperatures of the nanocomposites are higher than that of the corresponding pure polystyrene. The glass transition temperatures of nanocomposites increased with the increasing of silica contents, which were further ascertained by DSC.

关键词： silica nanoparticles surface modification styrene radical copolymerization nanocomposites

Synthesis and Characterization of Polyurethane/Poly (Urethane Modified Bismaleimide-Bismaleimide) IPNs

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Chinese chemical Letters 2000年第6期11卷 525-526页

作者： Yuan Li CAI Peng Sheng LIU (college of chemistry and {2. engineering, Xiangtan university, hunan 411105) Xiangtan Univ Coll Chem & Chem Engn Xiangtan 411105 Peoples R China

PU/P(UBMI-BMI) IPNs with excellent thermal stability and mechanical properties were synthesized and characterized. The interpenetrating occurs in the hard segment domains of PU, which leads to enhancement of hydrogen ... 详细信息

关键词： PU/P(UBMI-BMI) IPNs synthesis characterization