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

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 engineering, Hunan Institute of Science and Technology, Yueyang 414000,{3. 2 college of Chemistry and chemical engineering, Central South University, Changsha 410083.{3. 3.college of Pharmaceutical Science, Central South University, Changsha 410078,{3. department of Chemistry and chemical engineering Hunan Institute of Science and TechnologyYueyang 414000China college of Chemistry and chemical 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 27.6% 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

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Performance of Hyperspherical Harmonic Expansionon the Low-lying P and D States of Helium Atom

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chemical Research in Chinese Universities 2000年第4期16卷 351-355页

作者： WANG Yi-xuan, ZHUANG Bing-you and LIU Cheng-bu (School of Chemistry, shandong University, jinan 2.01.0, china) ({3. of Chemistry, Weifang college, Weifang 261043. china) shandong Univ Sch Chem Jinan 250100 Peoples R China Weifang Coll Dept Chem Weifang 261043 Peoples R China

The wave functions of the n1,3. (n=2, 3. 4) and the n 1,3. (n=3. 4, 5 ) low-lying states of the helium atom are expanded into the complete sets of the symmetrically adapted basis functions from hyperspherical harmonic functions in the angle part and of generalized Laguerre functions in the radial part respectively, and are then augmented by the simplest type of Jastrow correlation factor to incorporate electron-nucleus cusp only. The excellent agreement between the present nonrelativistic eigen-energies and those from the sophisticated configuration interaction (CI) method for the examined states indicates that the hyperspherical harmonic method can also be applied to the P and the D excited states of the helium atom.

关键词： Hyperspherical coordinate Helium atom Excited state

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Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2,3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,Nanjing University,Nanjing 210093.china 2. Nanjing college of chemical Technology,Nanjing 210048,china 3. Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse,Nanjing 21003.,china 1. State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. Nanjing college of chemical Technology Nanjing 210048 China 3. Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2MG, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

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Hybrid particle swarm cooperative optimization algorithm and its application to MBC in alumina production

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Progress in Natural Science:Materials International 2008年第11期18卷 1423-1428页

作者： Shengli Song~(a,b) Li Kong~a Yong Gan~b Rijian Su~(a,b) a department of Control Scienee and engineering,Huazhong University oF Science and Technology,Wuhan 43.074,china b {3. of Computer and Communication engineering,Zhengzhou University of light industry,Zhengzhou 450002,china department of Control Science and engineering Huazhong University of Science and Technology Wuhan 430074 China college of Computer and Communication engineering Zhengzhou University of Light Industry Zhengzhou 450002 China

An effective hybrid particle swarm cooperative optimization(HPSCO)algorithm combining simulated annealing method and sim- plex method is *** main idea is to divide particle swarm into several sub-groups and achieve optimization through coop- erativeness of different sub-groups among the *** proposed algorithm is tested by benchmark functions and applied to material balance computation(MBC)in alumina *** show that HPSCO,with both a better stability and a steady convergence,has faster convergence speed and higher global convergence ability than the single method and the improved particle swarm optimization *** importantly,results demonstrate that HPSCO is more feasible and efficient than other algorithms in MBC.

关键词： PSO Simulated annealing Simplex Cooperative optimization

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Multiary turbo code fitting for unitary space-time modulation and its MAP decoding algorithm

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Science china(Information Sciences) 2010年第12期53卷 2610-2619页

作者： ZHANG DaPeng 1,2,3.LU Ju 1,XU HongJi 1 & ZHANG XingYu 1 1 School of Information Science and engineering,shandong University,jinan {3.,china 2 State Key Laboratory of Integrated Services Networks,Xidian University,Xi'an 710077,china 3.department of Avionics engineering,First Aeronautical college of the Air Force,Xinyang 464000,china 1. School of Information Science and engineering Shandong University Jinan 250100 China2. State Key Laboratory of Integrated Services Networks Xidian University Xi’an 710077 China3. Department of Avionics Engineering First Aeronautical College of the Air Force Xinyang 464000 China

Unitary space-time modulation(USTM) fits for rapid Rayleigh flat fading channels as it can realize wireless communication when neither the transmitter nor the receiver knows the channel state information(CSI).However,an intrinsic problem is that only when the signal-to-noise ratio(SNR) is high can it give an ideal bit error rate(BER) *** existing bit-wise processing scheme of the combination of turbo code and USTM improves the BER performance and results in an unacceptable calculation complexity,storage and time delay *** this paper,we propose a multiary processing scheme and its corresponding multiary MAP decoding *** results verify that our scheme can reduce the system complexity while keep a good BER ***,we present the first analysis of the reason for the BER performance deterioration of the combination scheme at low SNR with the help of the definition of USTM.

关键词： multiple-input multiple-output unitary space-time modulation turbo code MAP decoding diversity

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Effects of Cationic Starch / Aluminum Hydroxide System on the Retention and Drainage of Wheat Straw Pulps

Effects of Cationic Starch / Aluminum Hydroxide System on th...

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第三届国际非木材纤维制浆造纸会议

作者： Liu Wenxia Sun Yanling Li Ronggang department of chemical engineering {3. Institute of light industry jinan 2.01.0 {3. china

＜正＞The effects of Cationic starch /aluminum hydroxide system on the retention and drainage of wheat straw pulp loaded with PCC were investigated. Aluminum hydroxide was prepared by the reaction of alum and sodium hydroxide in situ. By the investigation. we found that the cationic starch / aluminum hydroxide system exhibited remarkable effects on the retention and drainage of wheat straw pulps loaded with PCC （retention on particular） , and depended highly on pH, contact time of the furnish with alum before web formation, starch and alum dosage and the extent of pulp washing.

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Electrochemical performance of LiFePO_4 cathode material for Li-ion battery

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Rare Metals 2006年第z1期25卷 62-66页

作者： LI Shuzhong LI Chao FAN Yanliang XU Jiaqiang WANG Tao YANG Shuting engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China Department of Chemical Engineering College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China

In the search for improved materials for rechargeable lithium batteries, LiFePO4 offers interesting possibilities because of its low raw materials cost, environmental friendliness and safety. The main drawback with using the material is its poor electronic conductivity and this limitation has to be overcome. Here Al-doped LiFePO4/C composite cathode materials were prepared by a polymer-network synthesis technique. Testing of X-ray diffraction, charge-discharge, and cyclic voltammetry were carried out for its performance. Results show that Al-doped LiFePO4/C composite cathode materials have a high initial capacity, good cycle stability and excellent low temperature performance. The electrical conductivity of LiFePO4 material can be obviously improved by doping Al. The better electrochemical performances of Al-doped LiFePO4/C composite cathode materials have a connection with its conductivity.

关键词： lithium ion batteries LiFePO4 doping electrochemical performance

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Theoretical Studies on the Structures and Reactions of Halocarbenoids(Ⅰ)Structures and Stability of Chlorocarbenoid CHCl_2

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chemical Research in Chinese Universities 1997年第3期13卷 256-261页

作者： Li LI Ji-hai, FENG Sheng-yu,Liu Wei (chemical college,shandong University,{3., 2.01.0) shandong UNIV CHEM COLLJINAN 250100PEOPLES R CHINA

The chlorocarbenoid , CHCl2Li , was studied by means of ab initio molecular or- bital theory. Three equilibrium structures and two isomerization transition states were located. The calculations showed that the three-membered ring structure is the most stable. The 'classical tetrahedral' structure is not the local minimum on the potential energy surface.

关键词： Chlorocarbenoid isomeric structure Ab initio molecular orbital calcu- lation

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STUDY ON POLYMERIZATION OF OILLESS ALKYD RESIN WITH PHENYLTRIETHOXYSILANE

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Chinese chemical Letters 1992年第8期3卷 615-618页

作者： Shi Tai WANG Qing Si ZHANG Wan Yong MA shandong college of light {3.,jinan,2.01.0

Oilless alkyd resin modified with the silicoorganic compounds has been obtained successfully by *** appropriate proportion of silicoorganic compounds,the polymerized product has higher hardness and lustre than that of... 详细信息

关键词： high STUDY ON POLYMERIZATION OF OILLESS ALKYD RESIN WITH PHENYLTRIETHOXYSILANE than

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Study on Laboratory Method for Refining of SR Diesel Fuel

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china Petroleum Processing & Petrochemical Technology 2006年第3期8卷 57-60页

作者： Li Junling1 Zheng Tinglu2 Han Zhaping3.(1. college of Chemistry and chemical engineering,{3. Petroleum University (East{3.) Dongying 257061 2. shandong Jingbo Petrochemical Co. 3. shandong Donghai Petrochemical Co.) college of Chemistry and chemical engineering China Petroleum University (East China) Dongying 257061 China shandong Jingbo Petrochemical Co. China shandong Donghai Petrochemical Co. China

The method for refining the straight-run diesel fuel was studied in laboratory scale in order to make the acid number of diesel fraction comply with the standard while removing the naphthenic acids contained in diesel without causing environmental pollution. After comparing the effect of refining using three solvents, the isopropyl alcohol-HOA was specified as the best solvent. Meanwhile, the relationship between the acid number of diesel fraction and the amount of solvent used and the relationship between the concentration of solvent and temperature and the stability of diesel in terms of its acid number were also investigated. Experimental results had shown that when the mass fraction of the HOA-IPA solvent was 20% at a dosage of 17 mL of the solvent and a temperature of 3.℃, the acid number of the refined diesel fraction was 0.015 mg KOH/g with a good stability of acidity in the diesel fraction.

关键词： straight-run diesel deacidification refining naphthenic acid

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