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THE COORDINATION ADSORPTION OF AMINES ON CARBOXYL RESIN IN Cu^(2.) FORM FROM NON-AQUEOUS MEDIUM AND DESORPTION WITH ANHYDROUS ELUANT

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Chinese Journal of Polymer Science 2002年第5期20卷 439-444页

作者： Jia-zheng Li Zuo-qing Shi Yun-ge Fan The State Key Laboratory of Functional Polymer Materials for Adsorption and Separation, Institute of Polymer Chemistry Nankai univer.ity, tianjin 300071, {2. college of chemical Engineering Hebei univer.ity of Technology tianjin 300130 {2. Polymer Materials for Adsorption and Separation Institute of Polymer Chemistry Nankai University 天津 300071

The adsorption of aniline, N-methylaniline and N,N-dimethylaniline onto carboxyl resin in Cu2. form from water, ethanol and n-hexane have been studied. The results show that the adsorption affinities from n-hexane are higher than that from water, and nearly zero from ethanol. The separation factors for the adsorption of these three amines from mixed solution were also examined. The results of continuous column operations show that the breakthrough capacity of aniline from n-hexane reaches 90 mg/g dry resin in Cu2. form, and the amines adsorbed can be stripped with anhydrous ethanol effectively. Adsorption onto carboxyl resin in Cu2. form from non-aqueous medium and desorption with anhydrous eluant can overcome the run-off of Cu2. from the resin, and would show potential advantages in the separation of some water-insoluble natural products.

关键词： coordination adsorption adsorption selectivity amine ligand

Chiral Mn(Ⅲ) salen complex immobilized on imidazole-modified mesoporous material via co-condensation method as an effective catalyst for olefin epoxidation

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Science china Chemistry 2009年第9期52卷 1417-1422页

作者： LOU LanLan1, YU Yi1, YU Kai2. JIANG Shu1, DONG YanLing1 & LIU ShuangXi1 1 Institute of New Catalytic Materials Science, college of Chemistry, Nankai univer.ity, {2. 300071, china 2.college of Environmental Science and Engineering, Nankai univer.ity, {2. 300071, china Institute of New Catalytic Materials Science College of Chemistry Nankai University Tianjin China college of Environmental Science and Engineering Nankai University Tianjin China

An imidazole modified mesoporous material has been prepared through a co-condensation procedure and adopted to covalently anchor chiral Mn(Ⅲ) salen complex. The active centers in the as-synthesized catalyst were presented in the form of ionic species. The results of XRD, FTIR, DRUV-Vis, and N2.sorp-tion confirmed the successful immobilization of chiral Mn(Ⅲ) salen complex inside the channels of the modified support and the maintenance of the mesoporous structure of parent support in the immobi-lized catalyst. This heterogeneous catalyst exhibited comparable catalytic activity and enantioselectiv-ity to those of the homogeneous counterpart in the asymmetric epoxidation of unfunctionalized olefins. Furthermore, notably high turnover frequencies have been obtained over this heterogeneous catalyst for the relatively short reaction time and low catalyst amount, due in part to the ionic property as well as the uniform distribution of the active centers.

关键词： imidazole-functionalized mesoporous material chiral Mn(Ⅲ) salen complex co-condensation asymmetric epoxidation unfunctionalized olefins

NKC-9离子交换树脂细粉催化异丁烯水合反应动力学

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石油化工 2003年第9期32卷 775-778页

作者：王毅周明许春建南开大学化学学院天津300071 天津大学化学工程研究所天津300072

采用半连续反应过程 ,使用NKC -9离子交换树脂细粉 ,改变催化剂浓度、反应温度、反应压力、搅拌转速和异丁烯浓度等条件 ,对异丁烯水合反应动力学进行了实验研究。利用数学模型和非线性最小二乘法对实验数据进行了参数识别 ,得到了动力... 详细信息

采用半连续反应过程 ,使用NKC -9离子交换树脂细粉 ,改变催化剂浓度、反应温度、反应压力、搅拌转速和异丁烯浓度等条件 ,对异丁烯水合反应动力学进行了实验研究。利用数学模型和非线性最小二乘法对实验数据进行了参数识别 ,得到了动力学模型参数。应用该反应动力学模型对异丁烯水合反应过程进行模拟。

关键词：异丁烯水合反应叔丁醇离子交换树脂细粉反应动力学催化

Equations and their physical interpretation in numerical modeling of heavy metals in fluvial rivers

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中国科学：技术科学英文版 2010年第2期53卷 548-557页

作者： HUANG SuiLiang Numerical Simulation Group for Water Environment, tianjin Key Laboratory of Environmental Remediation and Pollution Control, Key Laboratory of Pollution Processes and Environmental Criteria of the Ministry of Education college of Environmental Science and Engineering, Nankai {2., tianjin 300071, china Numerical Simulation Group for Water Environment Tianjin Key Laboratory of Environmental Remediation and Pollution Control Key Laboratory of Pollution Processes and Environmental Criteria of the Ministry of Education college of Environmental Science an

Based on the previous work on the transport-transformation of heavy metal pollutants in fluvial rivers, this paper presented the formulation of a two-dimensional model to describe heavy metal transport-transformation in fluvial rivers by considering basic principles of environmental chemistry, hydraulics, mechanics of sediment transport and recent developments along with three very simplified test cases. The model consists of water flow governing equations, sediment transport governing equations, transport-transformation equation of heavy metal pollutants, and convection-diffusion equations of adsorption-desorption kinetics of particulate heavy metal concentrations on suspended load, bed load and bed sediment. The heavy metal transport-transformation equation is basically a mass balance equation, which demonstrates how sediment transport affects transport-transformation of heavy metals in fluvial rivers. The convection-diffusion equations of adsorption-desorption kinetics of heavy metals, being an extension of batch reactor experimental results and a major advancement of the previous work, take both physical transport, i.e. convection and diffusion and chemical reactions, i.e. adsorption-desorption into account. Effects of sediment transport on heavy metal transport-transformation were clarified through three examples. Specifically, the transport-transformation of heavy metals in a steady, uniform and equilibrium sediment-laden flow was calculated by applying this model, and results were shown to be rational. Both theoretical analysis and numerical simulation indicated that the transport-transformation of heavy metals in sediment-laden flows with clay-enriched riverbed possesses not only the generality of common tracer pollutants, but also characteristics of transport-transformation induced by sediment motion. Future work will be conducted to present validation/application of the model with available data.

关键词： heavy metals transport-transformation water-sediment-pollutants interaction fluvial rivers numerical modeling

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3 & FENG Hao4 1. Institute of Physics, college of chemical Engineering, Sichuan {2., Chengdu 610065, china 2. Institute of Theoretical Physics, Xihua Normal {2., Nanchong 637002. china 3. Department of Physics, china Oceanography {2., Qingdao 2.6003, china 4. college of Physics, Sichuan {2., Chengdu 610065, china Institute of Physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical Physics Xihua Normal University Nanchong China Department of Physics China Oceanography University Qingdao China college of Physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

CH_4部分氧化制氢Ni-CuZrSiO催化剂的研究

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燃料化学学报 2003年第6期31卷 531-537页

作者：王爱菊钟顺和天津大学化工学院天津300072

采用表面反应改性法制备了ZrO2.SiO2.ZrSiO)表面复合物,用等体积浸渍法制备了ZrSiO负载的Ni Cu双金属催化剂,并用IR、TPD、TPSR和微反技术考察了CH4、H2.和O2.催化剂表面上的化学吸附及反应性能。结果表明,在Ni Cu ZrSiO催化剂上存在着... 详细信息

采用表面反应改性法制备了ZrO2.SiO2.ZrSiO)表面复合物,用等体积浸渍法制备了ZrSiO负载的Ni Cu双金属催化剂,并用IR、TPD、TPSR和微反技术考察了CH4、H2.和O2.催化剂表面上的化学吸附及反应性能。结果表明,在Ni Cu ZrSiO催化剂上存在着Ni Cu金属位,Lewis酸位Znn+和碱位Zr O-三类活性中心;CH4和H2.在金属位和Lewis酸位Znn+和碱位Zr O-的协同作用下可形成解离吸附态;CH4、H2.和O2.Ni Cu ZrSiO催化剂表面上的主要反应产物为H2.CO2.选择性均在95%以上。

关键词：甲烷氢气制备选择氧化复合氧化物载体镍铜双金属催化剂 CH4

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对异丙基苯胺合成工艺的研究

石油化工 2005年第1期34卷 22-25页

作者：张鹏飞赵扬王聪天津大学化学工程研究所天津300072

在开发的HWC-3分子筛催化剂上研究了苯胺和异丙醇合成对异丙基苯胺的反应,得到了较佳的反应条件:温度615～640 K、压力0.1～0.5 MPa、空速1.0～1.5 h-1、苯胺与异丙醇摩尔比1.0～1.5.用精密精馏分离产物,共沸精馏回收未反应的苯胺和异丙... 详细信息

在开发的HWC-3分子筛催化剂上研究了苯胺和异丙醇合成对异丙基苯胺的反应,得到了较佳的反应条件:温度615～640 K、压力0.1～0.5 MPa、空速1.0～1.5 h-1、苯胺与异丙醇摩尔比1.0～1.5.用精密精馏分离产物,共沸精馏回收未反应的苯胺和异丙醇.对异丙基苯胺的选择性为94%,苯胺的单程转化率为19%,原料的总转化率在98%以上.较好地解决了设备腐蚀、'三废'污染、生产成本高、无法实现大规模连续化工业生产等问题.

关键词：苯胺烷基化异丙基苯胺催化合成异丙醇苯胺

Silylated and acetylated β-cyclodextrins for gas chromatographic stationary phases

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Journal of Central South univer.ity 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 chemical Engineering, Central South {2., Changsha 410083, china 2. college of Chemistry and chemical Engineering, Yueyang Normal {2. college of Chemistry and chemical Engineering Central South University Changsha China college of Chemistry and chemical Engineering Yueyang Normal University 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

Preparation of nanocrystalline BaTiO_3 ceramics

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Science china(Technological Sciences) 2009年第6期52卷 1730-1734页

作者： DENG XiangYun1,2.LI DeJun1,LI JianBao2.WANG XiaoHui3 & LI LongTu3 1 college of Physics and Electronic Information,tianjin Normal {2.,tianjin 300387,china 2.Materials and chemical Engineering Institute,Key Laboratory for Hainan Advantage Resources and Applied Technology in chemical Engineering Material of Ministry of Education,Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti,Hainan {2.,Haikou 5702.8,china 3 Department of Materials Science and Engineering,Tsinghua {2.,Beijing 100084,china Materials and chemical Engineering Institute Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Hainan U

The high-dense nanocrystalline BaTiO3(BT)ceramics with grain size smaller than 100nm have been successfully prepared by the two step sintering and the spark plasma sintering(SPS)*** successive transitions in nanograin BT ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions,similar to those in coarse BT ceramics,were revealed by in-situ temperature dependent Raman *** multiphase coexistence and the diffused phase transition character were demonstrated in the 8nm nanocrystalline BT ceramics.

关键词： nanocrystalline BaTiO3 ceramics preparation microstructure size effect