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    24 December 1992, Volume 13 Issue 12
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    Articles
    Studies on Hydrothermal Synthesis,Structure and Properties of NaSn2(PO4)3
    YUE Yong, XU Yue-Hua, PANG Wen-Qin
    1992, 13(12):  1491-1493. 
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    NaSn2(PO4)3 with NASICON structure was prepared by using hydrothermal techniques.The structure and conductivity of the samples were studied.The results show that the hydrothermal synthesis is a new route for preparing NaSn2(PO4)3 compound.This method is more convenient and effective than the conventional solid-state reaction method at high temperature and the pure phase and single crystal can be obtained easily.The structure and properties of the product obtained by hydrothermal crystallization are similar to those of the sample yieled by solid-state reaction.
    Studies on Synthesis Method and Properties of Heteropoly Complex Isomer of β-Nonatungstogallate
    QU Lun-Yu, BI Li-Hua, CHEN Ya-Guang, PENG Jun, YU Ming
    1992, 13(12):  1494-1497. 
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    A method----coordinating equilibrium competition----for synthesizing β-GaW9 heteropolyanion is reported here.The anion was separated in the form of salts with a general formula MaHb[β-GaW9O34H]·xH2O(M+=Na,K,NH4,Me4N,Et4N,a+b=10).The anion is the first β-isomer of Ga-containing heteropoly complexes and it can react with Mn2+ ion to form anion β-GaW9Mn3(H2O)3O3711-.All the complexes prepared here are characterized by IR,UV spectra,CV,ESR,μeff and DTA determinations.The results show that the title complex is reactive towards the coordination reaction and has a trivacance Keggin structure.
    Studies on the Formation of ZrO2/SO42- Superacid System
    Gao Zi, Chen Jian-min, Tang Yi
    1992, 13(12):  1498-1502. 
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    The crystallization,phase transition,dehydration and desulfuration of amorphous ZrO2 impregnated by H2SO4 under various calcination temperatures were studied with XRD,TG-DTG-DTA,SEMand chemical analysis methods.It was found that all these processes are evidently related with the formation of superacid.There are no water and free H2SO4 present in the ZrO2/SO42- superacid system,and the acid strength of the superacid system reaches the maximum as the amorphous ZrO2 transforms into a tetragonal crystal phase and slightly less than 1/3 of the surface Zr atoms are bonded with ZrO2/SO42- radicals.
    Identification of Structure and Investigation of Catalytic Properties on [Fe]ZSM-5 Zeolite Synthesized Without Amines
    YUE Ying, SHEN Wen-Xia, YEN Yi-Chun, DING Ying-Ru
    1992, 13(12):  1503-1506. 
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    [Fe]ZSM-5 Zeolite was synthesized successfully in a alkaline medium by the hydrothermal crystallization method without amines as the templates.The structure of [Fe]ZSM-5 zeolite was identified by means of XRD,TEM,IR,EPR,XPS and Mossbauer spectroscopies.It was proved that the structure of product is a typical ZSM-5 type and Fe3+ ions were introduced into the ZSM-5 framework and were in the lattice of zeolite with a tetrahedral environment.In the conversion reaction from methanol to gasoline he catalytic activity and selectivity of H[Fe]ZSM-5 zeolite synthesized without amines are the same as those of H[Fe]ZSM-5 zeolite synthesized with amine and are much better than those of H[Al]ZSM-5 zeolite.The selectivity for C5+ products is over 80% and the components of aromatic hydrocarbons and isoalkanes in C5+ products are over 75%.
    Synthesis of Potassium Trimanganononatugstosilicate Isomers and Their Property of Oxygen Atom Trasfer
    LIU Jing-Fu, LI Zhen-Zi, LI Bin, ZHAO Ben-Liang, LI Jin-Chang
    1992, 13(12):  1507-1509. 
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    The synthesis and catalysis of epoxidaton for olefin of a-and β-K6H4[SiW9O37 Mn3·(H2O)3]·xH2O are reported.The heteropolyacid salts have an ability to catalyze the epoxidation of olefin by PhIO,and the catalytic activity of them is probably related to the fact that the substituted Mn(II)can be oxidized to a higher oxidation state and the compound with a higher oxidation state has an oxidation property.
    Sythnesis and Effect of p-(Diethylamino)phenylgermanium Sesquioxide on Human Breastcarcinoma Cells in Vitro
    LU Chuan-Xin, ZHANG Shu-Gong, NI Jia-Zuan, NIE Yu-Xiu, CHEN Yu-Lan
    1992, 13(12):  1510-1512. 
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    The organogermanium compound p-(diethylamino)phenylgermanium sesquioxide was prepared with a simplified method,and the structure and properties were characterized.The results of the cancer cell culture show that in the concentration range of 1.00～0.01mmol/Lof the compound in the culture solution does not nearly inhibit the mitoses of human breastcarcinoma cells.
    Studies on Stopped-Flow Fluorescence Kinetic Method for Determination of Trace Titanium
    HUANG Hou-Ping, CAI Ru-Xiu, GAO Deng-Yun, ZENG Yun-e
    1992, 13(12):  1513-1516. 
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    The fluorescence kinetic characteristics of binary complex,Ti-3,5-dibromosalicylfluorone,was studied with a fluorescence kinetic analyzer(using the fluorescence spectiophotometer(Model 930,China)equipped with a self-made flowthrough cell).The influence of flow rate and sampling time on the sensitivity and the precision of method were discussed,Asimple rapid and accurate method of analysis for the fluorescence kinetic determination of titanium was developed.The interference of many ions can be eliminated by the kinetic method and it is satisfactory to apply this method to the determination of titaniutn in rare earth samples and synthetic sample.The limit of detection is 8×10-3 ppm.
    Studies on the Atomization Mechanism of Elements on the Graphite Probe Surface in the Graphite Furnace(Ⅹ)——The Atomization Mechanism of Strontium Nitrate
    DENG Bo, LIU Qiang
    1992, 13(12):  1517-1520. 
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    The objective of this study is to investigate the atomization mechanism of Sr(NO3)2 on the graphite surface by probe atomization combined with other instrumental methods.The atomization mechanism of Sr(NO3)2(s)was proposed,in which Sr(NO3)2 was decomposed into SrO(s)at first during heating then SrO(s)was converted into SrC2(s)and further into Sr(s).The atomization of strontium originates from vaporization of metal.
    A Study of Trace Argon Gas in Solid Determined by Gas Chromatography in Vacuum Melting
    WANG Shi-Tai
    1992, 13(12):  1521-1523. 
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    The paper describes a new method for determining a trace inert gas in the solid by gas chro-matography.It effectivelly solves the problem of feeding the gas specimen in low pressure,and optimizes purification condition of the gas specimen.Calibration curves were drawn with some standard substances,so the reliability of the new method established in the paper is proved.
    The Effect of the Concentration of the Buffer in the Capillary Zone Electrophoresis with PEG-400 Cross Linked Capillary Column
    YANG Guo-Liang, HU Liu-Jiang, CHU Xin-Hua, LIN Bing-Cheng
    1992, 13(12):  1524-1528. 
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    The effect of concentration of the buffer on the migration time,column efficiency,selectivity,resolution and the sampling amount were investigated in CZEwith the PEG-400 cross linked capillary column.Agroup of the peptides were used as the sample.The elution order of about 60% substance pairs changed when the concentration of the buffer changed only from 0.01 mol/Lto 0.04 mol/L.Such effect has been used as the foundation for the optimization of the condition.The peak height and area were increased with the increase of the same amounts of the sample.The relationship between the peak height and the concentration of the buffer was approximately linear.Attention should be paid when one calculates for the sample amount with the expression to the electric injection mode,where the concentration in the sample pool is different from that in the column.
    Studies on Reversible Optical Sensing Membrane for the Determination of Benzyl Amine
    WANG Ke-Min, OUYANG Wen, BIAN Ke-Jun
    1992, 13(12):  1529-1532. 
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    The reversible optical sensing membrane for the determination of benzyl amine is described.It incorporates dinaphthyl macrocyclic polyether as the ionophore of benzyl amine cation and lipophilic pHindictor in a plasticzed PVCmembrane.The competitive binding of benzyl amine cation and hydrogen ion in the membrane yields large absorbance changes which can easily be measured in the visible spectral range.The response performance of this sensor and its theoretical response equations are reported.
    Studies on the Response Characteristic of Microwave Induced Plasma Ionization Detector
    YUAi-Min, WANG Xu, JIN Qin-Han
    1992, 13(12):  1533-1535. 
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    The experimental parameters were examined in detail which affect the response characteristic of the new developed microwave induced plasma ionization detector for gas chromatography.Under optimum conditions,the analytical performance is improved.The sensitivity to benzene is 1.6×10-12 g/mL,and the linear range is 105.The result also shows that the detector is a concentration-type detector,and the main mechanism which makes the sample ionized is photoionization process.
    Differential Reciprocal Oscillographic Chronopotentiometric Titration
    ZHENG Jian-Bin, BI Shu-Ping, GAO Hong(H. Kao)
    1992, 13(12):  1536-1538. 
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    A new method called differential reciprocal oscillographic ehronopoientiometric titration is presented,it maked use of appearance or disappearance of a peak of depolarizer on differential reciprocal oseillogram to indicate the end point of titration.This method was applied to the titration of Pb2+,Cd2+,Ni2+,Co2+,Zn2+,Ga3+ and Cu2+ by EDTA or EGTA.The end point of titration is very easy to be observed
    Computer-Assisted Optimization of Selection of Synthetic Condition(Ⅰ)——Azodrin (Pesticides) Synthesis
    WANG Qin-Sun, SHAO Rui-Lian, YAN Bing-Wen, HAN Xian-Zheng, LI Hong
    1992, 13(12):  1539-1541. 
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    A computer-assisted method is presented for optimization of selection of reaction condition(Reactant concentration,molecular ratio and treatment time)in organic synthesis.The optimization method is based on a polynomial estimated from fifteen preliminary runs.This is followed by a computer scanning technique.The yield and content of product is used as the criterion.The validity of the optimization strategy is proved by applying to the technical Azodrin synthesis.Good agreement is ob-tained between the predicted and experimental results.
    Preparation and Characterization of an Ester-Containing Polymer Packing for High Performance Liquid Chromatography
    ZUO Yu-Min, LI Ai-Min, XUAN Guang-Shan, GUI Ming-De, YANG Xue-Jin
    1992, 13(12):  1542-1545. 
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    An ethylene glycol dimethylacrylate-styrene-divinylbenzene copolymer,used as packing for high performance liquid chromatography was prepared by a novel suspension polymerization process.The spherical particle sizes of the polymer are 5±2 urn.Some column parameters such as the permeability,theoretical plate height and selectivity were determined and compared with the data of similar packings in the literature.It has been found that the ester-containing polymer has not only the higher efficiency but also very good physical properties such as high rigidity and permeability,and that it is suitable for the separation of medium polarity mixtures of aromatic amines,phenols and cyclohex-anone peroxides.
    A Novel Secondary Metabolite from the Soft Coral Lobophytum Caledonense
    SU Jing-Yu, MENG Yan-Hui, ZENG Long-Mei, WANG Qi-Wen
    1992, 13(12):  1546-1547. 
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    Å novel secondary metabolite,lobocalone(1),was isolated from the soft coral Lobophytum caieilonen.se Tix Dur collected from the South China Sea.Its structure and relative stereochemistry were determined mainly by one and two-dimensional NMRand NOESYas(1R*,3R*,4R*)-3-(1'-methyl)vinyl-4-methyl-4-vinylcyclohexyl methyl ketone.
    Investigation of Bioactive Sesquiterpenoids from Celastrus Paniculatus
    TU Yong-Qiang, WU Da-Gang, ZHANG Xian-Min, HAO Xiao-Jiang
    1992, 13(12):  1548-1550. 
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    Three new β-dihydroagarofuran sesquiterpenoids were isolated from Celastrus paniculatus.Their structures were elucidated mainly on the basis of 2D NMR,1R and mass spectrometry.
    Studies on Chemical Ingredients of the Essential Oil of Cymbopogon Distans(Nees) W. Wats
    XUE Dun-Yuan, SONG Mao-Sen, CHEN Ning, CHEN Yao-Za
    1992, 13(12):  1551-1552. 
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    Cymbopogon distans(ness)W.wats was found to contain a-terpinene(27.8%),piperitone(18.2%),intermedeol(14.4%),and geranyl acetate(7.3%)as the main components in the essential oil by means,of preparative column chromatographic isolation and IR,1H NMRand MSspectrom-etry.Ail the 26 components were identified and estimated from the essential oil both by capillary gas chromatagraphy-mass spectrometry and by the Kovats index of the components on the OV-101 liquid phase.
    Determination of 4 Drugs of Ephedrines in Urine by GC/MSD
    GUI Kai-Rong, ZHOU Yi, ZHANG Chang-Jiu, CHEN Shi-Zhi
    1992, 13(12):  1553-1554. 
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    A GC/MSD SIM Method for separation and determination of 4 drugs of ephedrines in human urine is presented.This method is fit to the detection of ephedrines in doping control.
    Using Molecular Graphics, Molecular Mechanics,Quantum Chemistry and Electrostatic Potential Methods to Study Structure-Property Relationship on Pesticides(Ⅲ)——A Simple Method for Obtaining Optimum Conformation of Organic Molecule
    YAN Bo, LAI Cheng-Ming, LIN Shao-Fan, LI Zheng-Ming
    1992, 13(12):  1555-1557. 
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    A simple method for obtaining the optimum conformation of organic molecule is presented,which is in terms of rotating a part of molecule about a single bond one by one,and it is called the "single-bond progressive rotating method".By it we have calculated the optimum conformation of pesticide molecule ALLY,and compared it with similar structural molecule N-[2'-pyrimidinyl]-2-ethyl carboxylate-benzene sulfonylurea,of which the crystal structure has been determinated recently.It is found that the conformations between those molecules are approximate to same.
    α-Oxo Ketene Cyclic Dithioacetal Chemistry(Ⅴ)——Synthesis of β,β-1,3-Dithiopropylidene-α,β-unsaturated Aryl Ketones
    YANG Zhi-Yun, DONG De-Wen, LIU Qun , HU Yu-Lan, JING Feng-Ying, XIAO Yan-Wen
    1992, 13(12):  1558-1560. 
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    Seven title compounds were synthesized from aryl ketones with active methylene.It is proved that potassium tert-butoxide is an effective base in this procedure.When the proportion of substrate :carbon disulfide :potassium tert-butoxide i 1,3-dibromopropane is 1:1:2:1.0-1.1,the reaction gave the best yield.In the reaction,the proper concentration to potassium tert-butoxide is 0.4-0.6 mol/Land 1,3-dibromopropane is more effective than 1,3-dichloropropane as the halohy-drocarbon.In the products,2b～2g are new compounds.
    Synthesis of Spin-Labelled Anticancer Derivatives of 5-Fluorouracil
    WANG Yan-Guang, TIAN Xuan, LI Jing-Xin, CHEN Yao-Zu
    1992, 13(12):  1561-1563. 
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    Ten spin-labelled derivatives of 5-fluorouracil,as the potential anticancer agents,were synthesized.The structures of these new compounds were examined by IR,UV,MS,ESR and elementary analysis.The preliminary pharmacological tests show that some of the compounds possess anticancer activity against leukemia L1210 and utericervucak carcubbina U14 in mice.
    A Study of the Properties of Metastable Zone of the K2SO4 Aqueous Solution(Ⅳ)——The Effect of Impuritie Li+ on the Crystallization Process of K2SO4 Solution
    WANG Zi-Chen, GUO Xin-Xin, ZHANG Li-Hua, XU Bao-Kun, ZHAO Mu-Yu
    1992, 13(12):  1564-1567. 
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    The effect of Li+ ion on the metastable zone width and the nucleation characteristic parameters of K2SO4 aqueous solution were invesigated.It was found that the metastable zone widths were increased in the presence of Li+ .The influence of Li+ on the metastable zone width may be a result of its effect on the specific surface energy δ12 and the nucleation energy G(r*).
    Studies on Transient Response for Dehydrogenation of Ethylbenzene over FeZSM-5
    KAN Qiu-Bin, WU Zhi-Yun, ZHAO Zhong-Qing, PENG Shao-Yi
    1992, 13(12):  1568-1571. 
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    The transient response for dehydrogenation of ethylbenzene over ferrosilicate catalyst was studied.On the basis of the results of investigation for the surface adsorptive state of ethylbenzene from IRand EPR,the model of the reaction mechanism was given as follows;styrene was produced by dehydrogenation of activation adsorbed ethylbenzene over the catalyst.The model can be used to explain satisfactorily the transient response curves and kinetic behaviour of the reaction.
    Kinetics and Mechanism of the Consecutive Substitution Reactions of Bis (alkylxanthato)platinium(Ⅱ) with Piperidine in Benzene Medium
    WANG Shu-Qin, LIU Bao-Sheng, SHEN Shi-Gang, DING Tian-Hui, WANG An-Zhou
    1992, 13(12):  1572-1576. 
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    The title reactions have been studied by spectrophotometry.The products of the first and second steps of the substitution reactions are Pt(S2COR)(S2CN(CH2)5)and Pt(S2CN(CH2)5)2 respectively.The reaction order in each of the complexes is unity,and the apparent reaction orders in piperi-dine are in the ranges of 2.0 to 2.6 and 1.5 to 1.9 respectively.Amechanism involving an additive preequilibration was proposed.The rate equation derived from the mechanism explained all of the experimental results satisfactorily.The preequilibrium constants and the rate constants of the rate determining steps were calculated,and the structures of the adducts were discussed and reasonably infered,Activation parameters and isokinetic temperatures(β1=283±7K,β2=263±25K)were calculated.
    A Theoretical Study of Excited State Proton Transfer Reaction of 3-Hydroxypicolinamide
    XU Weng-Guo, FENG Ji-Kang, SUN Jia-Zhong
    1992, 13(12):  1577-1581. 
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    Using AM1 and INDO/SDCI method,a theoretical study of excited-state proton transfer reaction of 3-hydroxypicolinamide has been done.We get the potential energy surface,barrier,transition state and assign the spectra of related compounds theoretically,all calculated results are in good agreement with experiments.Then the mechanism of photochemical reaction and the possibility of applications are discussed.
    Studies on the Synthesis, Structure and Properties of Cluster [Fe(DMF)6][W2S6]
    ZHANG Zhi-Gui, WANG Tao, NIU Shu-Yun, DONG Wei-Tong, FAN Yu-Guo
    1992, 13(12):  1582-1585. 
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    A novel cluster [Fe(DMF)6][W2S6] was prepared by using(NH4)2WS4,FeCl3 and NaS2CNC5H10 as the reaction materials.Its structure was determined by X-ray method.The parameters of the crystal cell for the compound are a=0.8778(1)nm,b=0.9467(3)nm,c=l.1362(6)nm,α=71.506(1)°o,β=74.775(2)°,γ=74.775(2)°,V=0.84806 nm3 and Z=1.The structure was refined by block-diagonal matrix least square method,and the final agreement factor is R=0.0811.Moreover,the infrared spectra and UV-Visible spectra were measured.
    Catalytical Behaviour of Superionic Conductors in Oxidative Coupling of Methane
    BI Ying-Li, LI Li-Tao, ZHEN Kai-Ji, YANG Xiang-Guang, WEI Quan, LI Sen-Zi
    1992, 13(12):  1586-1589. 
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    The essence and common nature of the oxidation-coupling of methane are studied and explored.In order to increase C2 yield,the superionic conductors as the catalysts were added into the ionic conductors CaOand La2O3 for enhancing the charge transfer in the reaction.It is found that the type of charge transfer strongly influences the properties of the catalysts in the above reaction and C2 yield is coincident with the charge transfer ability of the added superionic conductors.
    Studies on the Structure and Properties of 9-Hydroxy-fluorene-9-carboxylic Acid
    YU Yun-Peng, ZHU Duo-Lin, YAN Da-Yu, ZHAO Zhu-Liu, WANG Jin-Fan, YE Xue-Qi
    1992, 13(12):  1590-1593. 
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    The IR,UVand 1H NMR spectra of 9-hydroxy-fluorene-9-carboxylic acid was determined and explained.Its geometry structure parameters were obtained by optimization with MNDO method and it is found that the parameters are consistent with the X-ray diffraction results of its methyl ester.The positions of 9-substituents is unsymmetrical to the molecular plane.The hydroxy and the carboxyl are located on the two sides of the fluorene plane respectively.
    Cesium-Selective PVC Membrane Electrode Based on a Newly Crown Ether
    ZHOU Jun-Ting, YAN Xiao-Ci, LUO Ming-Dao, QU Song-Sheng, YU Zong-Yuan
    1992, 13(12):  1594-1596. 
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    A cesium ion selective PVC membrane electrode based on 4,4'-ditert-butyl di-benzo-2i-C-7 is presented.The electrode has the best sensitivity and considerably good selectivity over alkali and alkaline earth ions in monocrown ethers.
    Preparation of PbS Ultrafine Particles in Different Chemical Micro-Circumstances and Studies on Their Spectra
    LI Shou-Tian, ZOU Bing-Suo, ZHANG Yan, XIAO Liang-Zhi, LI Tie-Jin, ZHAO Jia-Long, HUANG Shi-Hua, YU Jia-Qi
    1992, 13(12):  1597-1600. 
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    In this paper we report the preparation of PbS UFP(ultrafine particles)in different surficial chemistry circumstances and the study of their adsorption spectra and their emission and excitation spectra.At room temperature,the quantum size effect,especially,the separated peak structrues of the spectra were observed.The result indicates that the surficial chemistry micro-circumstances greatly influence the optical properties of the ultrafine particles.The PbS UFPmodified by a layer of AOT moiecule has an infrared luminescent band at 1.1 urn and for the PbS UFP modified by a layer of DBS molecule the infrared luminescent band was not observed.
    Studies on Bond Character of Phenyl Rare Earth Gadolinium Complex
    MENG Qing-Bo, LI Zhen-Xiang, LIN Guan-Yang, CHEN Wen-Qi, GUO Chun-Xiao
    1992, 13(12):  1601-1602. 
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    The electronic structure,bond character,and reaction mechanism of phenyl rare earth complex,C6H5GdCl2·4THF,have been studied by using INDO method.The results obtained show that the Lewis acidity of Gd ion is weakened and polarity of Gd-Cl bond is decreased in the ethyl ether with a weak polarity,and substitution of GdCl3 with phenyl lithium as soft base is forced.After electron-withdrawing phenyl substituted Cl,the positive charge of the rare earth ion is increased.The bond order of bond between phenyl and rare earth ion is larger than that of π bond between neutral benzene and rare earth ion,so the covalency of the former is larger than that of the latter.The redistribution of the valent charges caused by the phenyl coordination leads to the weakening of ortho and para C—H bonds of phenyl,and causes some reaction easily.
    Studies on Acidity of HZSM-5 Modified by Si(CH3)3Cl and Its Catalytic Behaviour in n-Hexane Aromatization
    JIAO Qing-Zhe, JIANG Da-Zhen, ZHENG Wei-Min
    1992, 13(12):  1603-1605. 
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    The surface properties of HZSM-5 zeolite modified by Si(CH3)3Cl were studied by TPD,IR,27A1 MAS NMR.Catalytic reaction of n-hexane aromatization was investigated by continuous-reaction.The coke of catalysts was measured by DSC.It was found that the concentration of the strong Bronsted acid sites decreased and that of the stronger Lewis acid sites increased after modification by Si(CH3)3Cl.The TPDpeaks of NH3,which were presumally attributed to the stronger acid sites,were decreased by the deposition of Si(CH3)3Cl on the surface of the zeolite.The conversion of n-hexane and selectivities of aromatic compounds were controlled by changing the concentration of the stronger acid sites.But aromatic compounds distribution can be attained by controlling the pore opening and channel of the zeolite.
    A Study of the Inclusion Phenomenon of Hexamethylenamine with Phenol-Type Compounds
    GUO Wen-Sheng, FU Xing-Ji, XU Yong-Ting, YANG De-Jun, LU Yang, WANG Shu-Chun, ZHENG Qi-Tai
    1992, 13(12):  1606-1608. 
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    This paper reports that the host species hexamethylenamine forms channel-type inclusion compounds with phenol type compounds,such as p-nitrophenol,catechol,resorcinol,hydroquinone,and p-hydroxybenzaldehyde.Their molar ratios(host/guest)are1:l,1:2,1:1,1:1 and 1:2 respectively,and melting points are 144～145℃,164℃(sub.),203℃(sub.),198℃(sub.)and 116～118℃ in the same sequence.The result of X-ray diffraction shows that the crystal of inclusion compound formed by the title host and p-nitrophenol belongs to triclinic system space group P1.The parameters are a=0.5899(1)nm,b=0.7056(1)nm,c=2.5186(11)nm,α=87.53(3)°,β=96.71(3)°,γ=90.0(2)°,Z=2.Because of the presence of random water molecules in the inclusion compound crystalline,R=0.138.The results of X-ray diffraction and IRof other inclusion compounds are also given.
    Synthesis and Characterization of 1-Octene/Penten-4-ol-1 Copolymer
    FENG Lin-Xian, XIANG Mao-Liang, DONG Wei-Min, FAN Zhi-Qiang
    1992, 13(12):  1609-1612. 
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    A polar monomer,4-pentenoxyl trimethyl siiane,was synthesized,copolymerization of l-octene with it over solvay TiCl3 /Al(i-Bu)3 catalyst was studied and the title copolymers having various hydroxyl group contents were obtained by hydrolyzing the product and were characterized by elementary analyses and infrared spectrometry.Moreover,the reactivity ratios of two monomers were determined:r1(octene)=2.28±0.15,r2(PTMS)=0.47±0.05.
    Graft Copolymerization of Styrene with Unsaturated Side Groups-Containing Polyoxyethylene and Properties of the Products
    XIE Hong-Quan, ZHANG Cong-Yun, GUO Jun-Shi, LIU Yong
    1992, 13(12):  1613-1616. 
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    Graft copolymerization of styrene with copolymer of ethylene oxide and allyl glycidyl ether was studied.The graft efficiency can reach about 50%.The crude products were purified with extractions and characterized with IRand 1H NMR.The complexes of the graft copolymers with LiClO4 exhibit a conductivity approaching 10-4 S/cm at 25℃ The graft copolymers possess good emulsifying property and phase transfer catalytic property in Williamson reaction.
    The Effect of Core-Shell Structure on the Mechanical Properties of PS/PA LIPN
    LI Yu-Wei, WANG Jing-Yuan, LIU Rui-Ying, TANG Xin-Yi
    1992, 13(12):  1617-1620. 
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    The effect of core-shell structure on the mechanical properties of PS/PA LIPN was systematically studied.Their dynamic mechanical and mechanical properties were investigated via changing feeding order and swelling time as well as using the method of multistage polymerization for interpene-tration.The results reveal that changing the feeding order leads to the change of core-shell structure.and then the great disparity in mechanical properties.The increase of swelling time and the use of multistage polymerization for interpenetrating evidently enhance the degree of interpenetration,therefore result in the inward shift of Tg,/sub> and the improvement of mechanical properties.
    Studies on Propylene Polymerization and Polymerization Kinetics Under Highly Active Catalyst Comprising Phthalic Ester
    WANG Hai-Hua, ZHANG Qi-Xing, RAO Guang-Jie, LIN Shang-An
    1992, 13(12):  1621-1625. 
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    The polymerization of propylene under highly active catalyst comprising phthalic esters 1,2-C6H4(COOEt)2,1,2-C6H4(COOCH2CH=CH2)2,1,2-C6H4(COOBu)2 as electron-donors has been studied.It was found that the PPtacticity would raise with increasing phthalic esters,and the catalytic activity decreases while the PPtacticity increases.By adding silicon compounds PhSi(OEt)3,Ph2Si(OMe)2,Ph2Si(OEt)2,(CH3)2Si(OEt)2,there are almost the same results.The kinetics of propylene polymerization has been investigated.The polymerization rate equation in good agreement with experimental evidence is expressed as:Vt-Va=(V0-Va)e-βt,The change in morphology of the catalyst was studied before and after adding phthalate ester by SEM.
    The Syntheses and Adsorption Properties of Some Aminated Crosslinked Polystyrene with Low Exchange Capacities as the Adsorbents for Gypenosides
    MA Jian-Biao, LI Jian-Min, WANG Li-Min, SHI Zuo-Qing, HE Bing-Lin
    1992, 13(12):  1626-1629. 
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    In order to develop the new polymeric adsorbents for gypenosides,a highly crosslinked polystyrene-type resin S-008(Ⅰ)was chloromethylated and then aminated with the mixed amines of dimethylamine/trimethylamine or diethanolamine/trimethylamine to afford ten amino resins(Ⅱ-Ⅺ)with low exchange capacities.Their chemical and physical structures were characterized and their adsorption properties were also determined.The results show that some of the resins possess high capacities and good selectivities in the adsorption of gypenosides from an aqueous extract of Gynostemma pentaphyllum(Thunb.)Makino.
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