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    24 May 1995, Volume 16 Issue 5
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    Articles
    Preparation and Structure of Monodispersed superfine Particles of Complex Rare Earth Oxides and Oxysulfides
    QIAN Hong-Tao, RUAN Shen-Kang, KANG Zhen-Chuan, SU Mian-Zeng
    1995, 16(5):  661-665. 
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    Monodispersed fine spherical particles(～100 nm)of complex rare earth hydroxy carbonates are prepared by hydrolizing mixed rare earth nitrates solution at elevated tempera ture in the presence of urea. By calcining the hydroxycarbonates at moderate temperature,complex rare earth sesquioxides(～70 nm)of C-type can be obtained.The mechnism of the decomposition of hydroxycarbonate at different temperatures have been verified to proceed through monoxydicarbonate, dioxymonocarbonate to sesquioxide of body-Centered structure by DTA,TGA,XRD and HREM. The experimental EDP diagrams of complex rare earth sesquioxides have been identified with those of calculated C-type structure. Complex rare earth oxysulfides of hexagonal structure can be prepared by firing a blend of complex rare earth hydroxycarbonate,S, Na2CO3and KH2PO4at 1000℃.
    Synthesis, Structure and Catalytic Hydrogenation of DinuclearPalladium(Ⅱ) Complex [Ph2P(o-C6H4CO)PdCl]2·2CH2Cl2
    GAO Jing-Xing, WANG Jin-Zhi, HU Sheng-Zhi, WAN Hui-Lin
    1995, 16(5):  666-669. 
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    The interaction of Pd (CH3CN)2Cl2and 1 equivalent of o-(diphenylphosphino ) benzaldehyde in refluxing dichloromethane gives dinuclear palladium(Ⅱ) complex [Ph2P(o-C6H4CO)PdCl]2,·2CH2Cl2by the intramolecular elimination of HCl. The complex has been characterized by analytical and spectroscopic methods as well as X-ray diffraction analysis.Crystal data: [Pd2Cl2(C19H14OP)2]·2CH2Cl2,,triclinic, P1, a =0. 9304 (3) nm, b=1. 0390 (2) nm, c=1. 1062(3) nm; a=102. 78(2), B=97. 35(3), Y=95. 25(2)°, V=1. 0264 nm3,M=1032. 17, Z=1, Dc=1. 670 g/cm3, u=13. 695 cm-1. F(000) =512, final R=0. 036 for 1945 significant reflections. The complex as a catalyst for homogeneous hydrogenation of olefin has been investigated.The results indicate that the title complex is an active catalyst for hydrogenation of acrylic acid.
    Synthesis and Crystal Structure of Polyanion [Se2Mo5O21]4-with Strandberg-type Structure
    HUANG Gui-Qing, ZHANG Shi-Wei, SHAO Mei-Cheng
    1995, 16(5):  670-673. 
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    By red-ox reconstructing (ROR) method, we synthesized and analyzed the het eropoly compound K3Na[Se2Mo5O21]·2H2O with Strandberg-type structure.The crystals are the polyanion, five MoO6octahedra are connected by edge sharing, and the two octahedra at the two ends are connected by conner sharing to complete the Mo5ring, the two SeNO3trigonal pyramids are attached to the ring from above and below the ring.
    Thermodynamic Studies on the N-Acetic Acid Substituted Tetraazamacrocycle and Its Lanthanide Complexes
    BI Jian-Hong, HU De-Yin, NI Shi-Sheng, XU Ji-De
    1995, 16(5):  674-677. 
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    The protonation constants of the macrocycle H4L (5, 7,12,14-tetramethyl-1,4,8,11-tetraazamacrocyclotetradeca-N',N", N"' N""-tetraacetic acid )were determined by poten tiometric titrations in 0.5 mol/L KNO3solution at 25+0.1℃,40+0.1℃ and 80±0. 1 ℃.The stability constants of the complexes of H4L with La3+,Nd3+, Pr3+,Sm3+,Eu3+,Gd3+,Dy3+,Yb3+were determined by the same method at 40+0. 1℃ and 80±0.1℃.The en thalpies of coordination reaction of H4L with H+in the solution were given.Experimental re sults show that the complexes have high stability.
    Syntheses and Structures of Trinuclear Iron Carbonyl ClustersContaining Carbenes from Cleaving of 2,4-Dithiohydantoins
    LIU Deng-Kui, CHENG Qing-Min, HU Xiang, LIU Qi-Wang, LIU Shu-Tang
    1995, 16(5):  678-682. 
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    The reaction of Fe3(CO)12with 2, 4-dithiohydantoins SCNHC(R1)(R2)C(S)NH(SL) yields the known Fe3(CO)9(u3-S)2and the five new open triangular iron carbonyl clus ters Fe3(CO)8(u3-S)2(L)1-5. It was found that the coordinated ligands in the clusters 1-5 besides eight terminal COligands are two sulfito Satoms and a heterocyclic carbene Lwhich was formed from the cleavage of the ligand precursor SL. The formulas and structures of these clusters were characterized by elementary analysis, IR, 1HNMR and MS techniques and the molecular structure of 3 was determined by X-ray diffraction analysis. The sp2bond ing character of the carbon (carbene) atom of fragmental 2,4-dithiohydantoin: CNHC(CH3)2C(S)NH shown clearly in 3 and the Ccarh.-Fe bond length of 0. 1898 nm cor responds to other iron stabilized carbenes. This carbene ligand displaced a terminal axial CO of the basal Fe(1) atom and locates in a vertical position to the Fe (1)S(1)Fe(3)S(2) distort ed basal plane. The geometry of Fe3(CO)9(u3-S)2has been maintained in 3, but some of Fe-S and Fe-Fe bond lengths have been changed.
    Studies on Structure of the Substrate in the Oxidation Reaction Catalyzed by Peroxidase
    CHEN Lie, CHANG Wen-Bao, CI Yun-Xiang
    1995, 16(5):  683-687. 
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    This paper studies the competitive inhibitory actions of twenty-three substances on the oxidation reaction system of chavicol with H2O2catalyzed by peroxidase.The compu tation method of the inhibitory constant Ki, is presented. With comparing and analysing the values of all kinds of substances Ki,the best structure of the substrate in the oxidation reac tion catalyzed by peroxidase is suggested.
    Studies on Structure-Property Relationship Between ColorReagents and Sensitivity of Their Color Reactionswith Ytterbium by Topological Indices
    LI Hua, XU Lu, SU Qiang
    1995, 16(5):  688-691. 
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    In this paper Amtopological indices and molecular connectivity inidces have been applied to multivariate analysis in structure-property studies.The topological indices of twenty asymmetrical phosphone bisazo derivatives of chromotropic acid have been calculated.The structure-property relationships between color reagents and molar absorptivity of color reactions with ytterbium have been studied by Amindices and molecular connectivity indices.Good results have been obtained.
    Resolution of Overlapping Polarographic Waves by On-line Microcomputer Based Kalman Filter
    LU Xiao-Hua, CHEN Guang-Dong
    1995, 16(5):  692-695. 
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    By using the parallel printing I/O port of PCmicrocomputer and the graph plotter port of MP-1 stripping analyzer, an interface circuit was designed for data acquisition. After the pretreatment of the polarographic signals, Kalman Filter was used in resolution of the overlapping polarographic waves of mixtures of in and Cd. The results showed that when the relative concentration of in and Cd was 1: 16 to 13: 1, the satisfactory quantitative results of two components can be obtained with this on-line microcomputer based Kalman Filter.Some parameters in the process of Kalman Filtering were discussed as well.
    Determination of Trace Amounts of Metal by High-Performance Liquid Chromatography-Spectrophotometry
    CHENG Jie-Ke
    1995, 16(5):  696-703. 
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    This paper reviews the determination of trace amounts of metal ions and their sep aration by high-performance liquid chromatography-spectrophotometry adopting precolumn derivatization with the emphasis on the investigation of precolumn derivatizing reagents in re cent years.The substituent groups of reagents, auxiliary complexing agents and the mecha nisms of chromatographic retention of metal complexes are discussed.
    An Array of Piezoelectric Crystal Sensors with Plasticized PVC Coatings Used as Perfume Odour-Sensing System
    CAO Zhong, LIN Hui-Gai, WANG Bin-Feng, WANG Ke-Min, CHEN Ze-Zhong, YU Ru-Qin
    1995, 16(5):  704-706. 
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    The traditional method for the preparation of PVC ion-sensitive membrances has been adapted to the formation of adsorptive coatings on a piezoelectric crystal sensor (PCS).Besides the PVC matrix and di-n-octylphenyl phosphate(DOOP) plasticizer, 12 adsorptive materials have been selected from 68 compounds by cluster analysis: squalane, polyethylene glycol-20M, dodecyldimethylaniline, thionalid, polyethylene glycol octylphenyl ether, suc cinimide, diacetyl cellulose, benzyltetradecylidimethylammonium chloride, 8-hydroxyquino line, N-(2-hydroxylbenzyl ) didecylamine, dimethylpropaneldiol succinate, triton X-305.The frequency shift data obtained from the sensor array responding to four commercial per fume vapours are first autoscaled and then treated by principal component aualysis. The two dimensional display of autosealed data measured by the sensor array shows well-defined clus ters for different perfume odours.The sensor array has also been applied to classification of commercial spirituous liquor,wine and soft drink samples,as well as aliphatic alcohol homo logue, and propanol isomer samples. The response characteristics of sensor arrays have been investigated experimentally.
    Studies on Signal-to-Noise Ratio and Analytical DynamicRange in ECHELE/CCD ICP-AES
    YANG Peng-Yuan, WANG Xiao-Ru, YING Hai, QIN Shi-Dong, WAN Ting, HUANG Ben-Li
    1995, 16(5):  707-709. 
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    This paper reports the experimental study on the ECHELE/CCD ICPAES. The results show that the S/N ratio enhancement is particularly important in the signal process due to the low sensitivity of CCD in UV range. The effect of CCD noise pattern of dark cur rent and of sensitivity, and their correction methods are described.The analytical dynamic range of CCD has been expanded to the six orders of magnitude, by means of multiple-time integration or multiple-line integration.
    Quantitative Structure Activity Relationship Study of Fungicidal O-Ethyl-N-isopropylphosphoro(thioureido) thioates
    YANG Hua-Zheng, WU Ye, REN Kang-Tai, ZHANG Yu-Fen
    1995, 16(5):  710-714. 
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    The fungicidal activity of a series of O-ethyl-N-isopropylphosphoro(thioureido) thioates was studied. It was found that the activity of these compounds was highly dependent upon the substituents attached to the nitrogen atom and this is a kind of broad spectrum fungicide.The quantitative relationship between the structure of the compounds and their fungicidal activity on the rice sheeth blight (Pellicularia sasakii),wheat bead blight (Gib berella saubinetii), apple alternaria fruit rot (Alternalia mali), cotton soreshin (Rhizoolonia solani),and cercospora spot of sugar beet (Cercospora belocola) were analyzed,respectively,using the physicochemical parametres of the substituents and regression analysis.The re sults were used in guiding the synthesis of higher active compound and verified.
    Studies on the Oxidation Performance and Reaction Product of Rhus Laccase in Reverse Micelles
    DU Yu-Min, ZHANG Jin-Mei
    1995, 16(5):  715-718. 
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    The oxidation of o-aminophenol catalyzed by Rhus Laccase(R. L.) solubilized in AOT/n-octane/H2O reverse micellar solution was studied. The optimal conditions observed for R. L. in reverse micelles are T=40℃, pH=7. 6 and R =[H2O]/[AOT]≈18. It was found that in reverse micelles at 30℃ for 15h in R=6. 2, the residual activity of R. L. re mains as high as 82%, and a little inhibition occurs when 1. 0×10-3mol/L Zn2+, Fe3+,Mg2+ exist in water pools. o-Aminophenol was oxidized by R. L. in reverse micelles and aqueous solution respectively,and it indicated that both of the main oxidation products are 2 amino-3-phenoxazinone. However, the yield of the oxidation product in the reverse micelles is 1.5 times as much as that in the aqueous solution.
    Liquid Crystallines Study(Ⅰ)──Synthesis and Properties of 4'-Acyl-4-biphenylol Esters
    LU Wan-Fang, ZHANG Zhi-Yong, SHI Yao-Zeng
    1995, 16(5):  719-724. 
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    Biphenyl esters are useful and important materials for liquid crystal dispiays. Re cently it is well known that the presence of an acyl terminal group which atteched with its carbonyl carbon atom directly to an aromatic core,in liquid crystalline compounds would usually increase both the molecular rigidity and polarity, and as a result, the compounds could show some better mesomorphic properties than those that contain the same molecular backbone but carry only R-or RO-terminal chains.Thus, we synthesized eight new 4'-acyl-4-biphenylol esters 5a-hwith 4-biphenylol as starting material to study the effect of molecular structure on phase behavior of these esters. Chemical structures of these com pounds were determined by IR, 1HNMR, MS and elementary anaiysis. Their liquid crystal properties were tested by hot stage polarizing microscopy and differential scanning calorime try. Except compound 5h, these compounds have a wide tempetature range of mesophase and high thermostability. Some of them show a monotropic phase transition in the Scphase. The SA-Scphase transition of compound 5cis a second type phase transition. Compound 5g,though there is no chiral carbon in the molecule, displays a stripped focal conic texture in the Scphase.The effect of molecular structure on liquid crystal properties was discussed.
    Synthesis and Intramolecular Hydrogen Bonding of Symmetric Dipyrrylmethanes
    CHEN Qing-Qi, WANG Chang-Qi, CHENG Ling-Jiang, MA Jin-Shi, JIN Sheng
    1995, 16(5):  725-729. 
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    The title compounds were prepared by converting ethyl 5-methylpyrrole-2-car boxylates into corresponding 5-methyl substituted pyrroles oxydized by surfuryl chloride,bromine,or lead tetraacetate, and then self-condensed without separation and purification.The 1HNMR analysis and molecular conformation computation revealed that strong in tramolecular hydrogen bondings exist in dipyrrylmethane 4band 4c(3,3' substituents are for mate and acetate esters),while very weak or no intramolecular hydrogen bonding exists in other dipyrrylmethanes.
    The Synthesis of 3-Arylaminomethyl-2,4-dihydroxyacetophenone or 8-Acetyl-3-aryl-3,4-dihydro-5-hydroy-2H-1,3-benzoxazine and Their Interconversion
    ZHU Zhi-Hong, XU Xiu-Juan
    1995, 16(5):  730-734. 
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    The Mannich reaction of 2,4-dihydroxyacetophenone, 37% formaldehyde solution and arylamines has been studied in ethanolic-HCl solution or 95% ethyl alcohol. Two differ ent kinds of compounds are obtained. Five 3-arylamino-methyl-2,4-dihydroxy (5) and five sacetyl-3-aryl-3,4-di-hydro-5-hydroxy-2H-1, 3-benzoxazine (6) are prepared.All of them are first reported. The structures of sand 6 are deduced by elemental analysis,IR,1H NMR,MS and UV analysis. The interconversion between5and 6 has also been real ized successfully.
    Quantitative Structure-Activity Relationship Studyof Herbicidal α-Substituted Acetamides
    YANG Hua-Zheng, LI Quan-Zhong, CHENG Mu-Ru, REN Kang-Tai
    1995, 16(5):  735-739. 
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    The quantitative relationship between the structures of N, N-disubstituted-α-chloroacetamide and α-(O,O-dialkyl phosphorodithioy) acetamide and their herbicidal activi ty on the barnyard grass,Echinochloa cruss-galli, was analyzed respectively. We found that their hydrophobicity and steric dimension of substituted amino group strongly affect their herbicidal activity. In two QSAR equations, the optimum steric dimension values (B1) were approximate, but their optimum hydrophobicity values (π) differ from each other.It was suggested that there may be the same mode of action for the two kinds of compounds.
    Studies on Condensed Heterocyclic Compounds (Ⅸ)──Synthesis Of 3-Aryl-6-(2, 4-dichlorophenoxyethylamide)-striazolo[3,4-b]-1, 3, 4-thiadiazoles
    ZHANG Zi-Yi, ZHAO Lan, LI Ming, LI Zheng-Ming, LIAO Ren-An
    1995, 16(5):  740-743. 
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    3-Aryl-4-amino-5-thiol-1, 2, 4-triazoles were condensed with 2, 4-dichlorophe noxyethylacy isothiocyanate to obtain 10 novel s-triazolo [3, 4-b]-1, 3, 4-thiadiazoles 3a-jin moderate yieid. Their structures were,confirmed by elementary analysis, IR, 1HNMR and MS. The possible mechanism of this reaction was also discussed.
    Studies on the Inhibiting Action of PCMB to Arginase Using Microcalorimetry
    LIANG Yi, WANG Cun-Xin, WU Ding-Quan, QU Song-Sheng, ZOU Guo-Lin
    1995, 16(5):  744-747. 
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    Microcalorimetry was used to study the inhibiting action of p-chloromer curibenzoic acid(PCMB)to L-arginine hydrolysis with arginase, PCMB was determined as a competitive irreversible inhibitor and the second-order rate constant of the reaction between PCMB and arginase was k+0=92. 17 L/(mol· s)at 298.15 Kand pH 9.4.The properties of the active site of arginase were investigated by using PCMB as a modifying agent.The results of chemical modification reveal that arginase contains 3 reactive cysteinyl residues at most but these residues do not belong to the active site of arginase. The modification of 3 cysteinyl residues by PCMBled to～50% inhibition of arginase activity.
    Studies on the Magnetic Circular Dichroism of Some New"Picket Fence"Porphyrins and Their Metal Complexes
    HU Jing, CHANG Jun-Biao, QIAN Fa-Cheng, WU Yang-Jie
    1995, 16(5):  748-752. 
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    The magnetic circular dichroism spectra of three kinds of new"picket fence"pro phyrins:meso-tetra[α,α,α,α-O-(2-furan carbonylaminophenyl)] porphyrin( 1). meso-tetra [α,α,α,α-O-(2-thiophenoylaminophenyl)]porphyrin ( 2).meso-tetra[α,α,,α-O-( 4'-carbony lamino-benzo-15-crown-5)-phenyl]porphyrin ( 3) and their metal complexes: 1-FeCl,2-Cu,3-FeCl,3-Zn,were studied. The relation between molecular configuration and magnetic cir cular dichroism,electron transition,was discussed according to the Buckingham-Stephens e quation.
    Two New Flavone Glycosides from Mosla Chinensis Maxim
    ZHENG Shang-Zhen, SUN Li-Ping, SHEN Xu-Wei, WANG Yi
    1995, 16(5):  753-755. 
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    Two new compounds were obtained from Mosla chinensis Maxim. and their struc tures were elucidated as 5-hydroxy-6-methyflavanone-7-O-β-D-xylopyranose(3→1)-β-D-xy lopyranoside, rhamnocitrin-3-O-β-D-apiosyl(1→5)-β-D-apiosyl-4'-O-β-D-glucoside on the basis of spectral methods (EIMS, IR,1HNMR,13CNMR)including 2DNMR techniques and chemical methods.
    A Study of the Nonradiative Decay Process of N,N-Dimethylamino Enone Derivatives with Different Limited Structures
    WANG Peng-Fei, WU Shi-Kang
    1995, 16(5):  756-760. 
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    In this work, the nonradiative decay process of several N,N-dimethylamino enone derivatives with different limited structures as the electron donating group has been studied in different viscosities and at different temperatures. The variation of nonradiative decay pro cess has been observed in the media with different viscosities and polarities. In nonpolar me dia with lower viscosity,the nonradiative decay is mainly caused by the internal conversion of nπ*-ππ*interaction.Whereas in polar media with high viscosity,the internal rotation loss is the majorly nonradiative decay process.
    Quantum Chemical Study of SiH3NO2-SiH3ONO Tautomerism
    TNAG Zuo-Hua, CHEN Jian-She, SUN Ze-Min, TIAN An-Min, YAN Guo-Sen
    1995, 16(5):  761-764. 
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    MNDO method has been employed to study the reaction pathway and the struc tures of the reactant,the product and the transition state for the reaction of SiH3NO2 SiH3ONO tautomerism. This study has shown that the reactant and the product are stable,and the activation energy of the reaction is very low.
    Interaction Parameters of the Excess Gibbs Free Energy Between Solutes in Formamide
    BAI Tong-Chun, ZHANG Xin-Kuan, LU Yan, LU Jin-Suo
    1995, 16(5):  765-769. 
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    The retention values of eight organic solutes in stationary solution of formamide+ acetamide, formamide + urea and formamide + sodium perchlorate at the temperature of 298.15 Kwere measured by a gas-liquid chromatographic method(GLC.The McMillan Mayer's solution theory was used to relate the excess Gibbs free energy of the system to a se ries of pair and triplet interaction parameters. The relationship of the interaction parameters with the retention values of GLC was deduced by using the thermodynamic method.From experimental result, the values of pair and triplet interaction parameters, gij and gijj,be tween solutes have been fitted by a least square method.The information about the solute solute interaction and the effect of solvent on the interaction have been discussed.
    Studies on the Structure of LiNi0.3Co0.7O2and the Behaviorof Its Lithium Battery
    ZHANG Fu-Ping
    1995, 16(5):  770-774. 
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    XRD, XPS and CV have been used to study the structure of LiNi0.3Co0.7O2 and the behavior of its lithium battery. It is shown that LiNi0.3Co0.7O2 has a space group R3m with hexagonal parameter a=0. 2826 nm,c=1. 4130 nm. Li2O was identified on its surface. Its lithium battery exhibited a discharge capacity of 120-140 mA. h. g-1at the rate of 0. 5-0. 1 mA. cm-2in the voltage range of 4. 30-3. 00 Vin 1mol. L-1LiClO4/PCsystem. The discharge mechanism of the battery involved a two-stage Li+intercalation in LiNi0.3Co0.7O2.Also, the chemical diffusion coefficent of Li+in LixNi0.3Co0.7O2 is about 1-7×10-8cm2· s-1in the range of x from 0. 775 to 1.
    A Kinetic Model of Nonadiabatic Electron Transfer andIts Application to O2O2-→O2-O2
    LI Xiang-Yuan, TIAN An-Min, HE Fu-Cheng, YAN Guo-Sen
    1995, 16(5):  775-778. 
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    the semiclassical model for nonadiabatic electron transfer has been described.Some new features for the relations between the energy barrier (Ec) at the crossing point and the activation energy(Ea) in the Arrhenius rate law have been revealed.The complex, reac tants, and the transition state for the colinear reaction have been optimized at 4-31G augmented with a set of anion diffuse functions. After a successful UHF SCFcalcula tion due to a electron-located initial guess, the authors have obtained the electron transfer matrix element VAB=7. 0 kJ/mol, the energy barrier Ec=28. 4 kJ/mol, the rate constant k=9. 2×108/s at 300 K. The discussions for the theoretical model and the calculated results have been made.
    NMR Study on Resistance Type Humidity Sensors
    HUA Shi-Ying, WANG Jia-Yu, XIN Yao-Quan
    1995, 16(5):  779-781. 
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    Three resistance type humidity sensors (polyethyl-enimine, polyethyl-ammonium salt and PEO) were studied at various temperatures and humidities by 1HNMR. The hu miditive sensibility mechanism of these sensors was proposed through the change of chemical shifts. The active hydrogen in the three materials reacts with H2O to form new active hydro gen, and the exchange interaction of new active hydrogen with old ones is very fast. At the same time, the current carriers are generated. As a result, the resistance of materials is de creased with raising humidity.
    ESR Study of Oxido-reduction Specificity of Heteropolyacid Salts Catalysts Containing Various Alkali Metals
    ZHENG Ying-Guang, DONG Feng-Xia, WU Tong-Hao, JIA Ji-Fei
    1995, 16(5):  782-785. 
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    The oxido-reduction and reduction-reoxidation specificity of heteropolyacid salts containing various kinds of alkali metals used for one-step oxidition of isobutyraldehyde to produce methacrolic acid was studied by ESR method. The effects of alkali and transition metals on oxido-reduction specificity of catalysts were discussed. Oxido-reduction capability of transition metal Cu, V, Mo in catalysts was compared. The effect of the behaviour of easy oxidiation of Cu+on catalytic activity was also analyzed.
    The Structure of C60NH2+and a Theoretical Prediction ofIts Electronic and NMR Spectra
    FENG Ji-Kang, TENG Qi-Wen, SUN Jia-Chong
    1995, 16(5):  786-790. 
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    The INDOseries methods are used to study the two structures of C60NH2+:one is C2v geometry with a bridging NH2+across the bond between two fused six-membered rings in C60; another is Cs geometry with a bridging CH2 across the bond between a five-and a six membered rings. From the calculated results, including the total energy, LUMO-HOMO gap, the most stable isomer of C60NH2+should be the C2v geometry. Our calculations also find that this C2v isomer has a protonated aziridine structure (bridging C15-C30 bond length is 0. 1520 nm, bond-order is 0. 9097). The electronic spectra of two isomers of C60NH2+have been calculated and their NMR spectra have been discussed. They are theoretical predic tions.
    Studies on Preparation of Iron,Cobalt and Copper Phthalocyanines/Y Zeolite, Characterization andTheir Catalysis for Hydroxylation of Phenol
    QI Xing-Yi, WANG Guo-Jia, ZHAGN Wei-De, YE Xing-Kai, WU Yue
    1995, 16(5):  791-795. 
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    Iron, cobalt and copper phthalocyanines/Y zeolite, denoted as FepcY,CopcY and CupcY respectively,were prepared. The formation of metal phthalocyanine compounds with in the cages of Yzeolite and their crystal structures were determined by elementary analyses,IR,UV-Vis,TG, BET, and XRD methods; The influence of experimental parameters upon phenol conversion and product selectivities was investigated as well.
    Promoting Catalysis of Anodic Oxidation of Mn2+to Mn3+Ionson Pt and PbO2 Electrodes by Silver(Ⅰ) Ion
    JIN Shi-Xiong, WANG Lan, ZHOU Wen-Feng
    1995, 16(5):  796-798. 
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    The influence of Ag+ions on the evolution of O2 and the anodic formation of Mn3+at Pt and Pb IPbO2 anodes was investigated in concentrated sulfuric acid solutions. The ki netic data related respectively to Mn3+anodic formation and O2 anodic evolution at Pt and Pb |PbO2 anodes in mixed H2SO4-MnSO4 solutions were measured by resolving the steady-state polarization curves. The Tafel slope of steady-state-lgi relationships for Mn3+anodic for mation reaction is close to 2×2. 303RT/βF, whereas for O2 anodic evolution it is close to 2. 303RT/βF(with β 0. 5). The influence of Ag+ions on the kinetics of evolution and Mn3+anodic formation at Pt and Pb|PbO2 electrodes was compared as a function of Ag+ions concentration. The O2 evolution and Mn3+formation rate increased uniformly with increasing Ag+ions concentration in the electrolytes. The kinetic data show that Mn3+anodic formation (i(Mn3+)) and O2 anodic evolution (i(O2)) increased by Ag+ions. Since the effect on I (Mn3+)was larger than that on i(O2) at the Pt electrode and smaller than that on i(O2) at the Pb |PbO2 electrode, the current efficiency of Mn3+formation increased at the Pt electrode and decreased at the Pb |PbO2 electrode.
    The Study on the Chain Extension Reaction of MDI and TDIT erminated Polyester Prepolymers with Extenders
    LUO Xiao-Lie, LIU Jin, HU Ke-Liang, MA De-Zhu
    1995, 16(5):  799-803. 
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    The effects of the hard segment structure on the chain extension reaction kinetics of MDIor TDIterminated PEPA-prepolymer with diamine(MOCA) and polyol(TMP) have been studied by FTIR method systematically. The reaction rate constants and activation en ergy for these systems have been measured. The chain extension reactions in these systems are found to be reactions of second order. The chain extension reaction of NCOterminated PEPA-MDI-prepolymer with MOCA or TMP is faster than that of PEPA-TDI-prepolymer with the same extenders. The activation energy of the chain extension reaction of NCOter minated PEPA-prepolymer with MOCA is much lower than that with TMP.Such chain ex tension reaetion difference has been discussed.
    Kinetics of Non-Isothermal Phase Transition of Poly(ester-imide)
    DONG De-Wen, NI Yu-Shan, ZHUANG Hui-Yan, CHI Zhen-Guo, CHEN Yu
    1995, 16(5):  804-807. 
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    Based on Jeziorny theory, the kinetics of phase transition of poly(ester-imide) has been determined under non-isothermal condition by using differential scanning calorimetry (DSC).Avrami exponent n, kinetic parameters Gcand rate constant Zcwere derived and discussed.
    Studies on Structure of EO/THF Random Copolyether(Ⅱ)──NMR Studies on Solution Action and Complex
    ZHANG Jian-Guo, WU Yi-Jie, JING Feng-Ying, PEI Feng-Kui, TAN Hui-Min
    1995, 16(5):  808-811. 
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    The special action of TEO solution was investigated by 1D,2D-NMR in CDCl3.For the present measurements, when the concentration of TEO was higher in CDCl3the chemical shift difference(△δ) and the peak number of 13CNMR spectrum were changed with increasing the solution concentration. At lower concentration (<3 % V/V), the peaks will be closed together for-CH2O-resonance carbon and it is not the appearance of the narrowed.When temperature was changed, the △δ value was contrary to the solvent effect. So, the shifts of the resonance carbon in the NMR spectra indicated clearly that the complex forma tion for the system of CDCl3, and TEO molecular interaction were affected by the experiment temperature and the solution concentration.
    Synthesis of a New Chiral Liquid Crystal with Schiff Base Groupand investigation of Temperature-depending FTIR Spectra
    TIAN Yan-Qing, LUO Xu-Yang, SU Feng-Yu, ZHAO Ying-Ying, TANG Xin-Yi, ZHAO Xiao-Guang, ZHOU En-Le
    1995, 16(5):  812-815. 
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    Anew chiral liquid crystal with Schiff base group has been prepared. The struc ture of liquid crystal was confirmed by elementary analyses and 1HNMR. Its phase transi tion was investigated by polarized optical microscope, DSC and temperature-depending FTIR spectra.The results showed that the chiral Schiff base showed monotropic phases behavior in certain temperature range, the phase sequence is I-N-SB-SG-K on the cooling sequence.
    Effect of Coordination Between Polymer Chains on the Solution Behavior of Zn-SIIR/PSVP Blends
    ZENG Zhao-Hua, FENG Ke, LI Zhuo-Mei
    1995, 16(5):  816-819. 
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    Ionic coordination between zinc sulfonated butyl rubber(Zn-SIIR) and styrene-4 vinyl-pyridine copolymer(PSVP) in solution was investigated. It was found that viscosity of the blend solution varied with the composition and attained maximum as the molar ratio of zinc sulfonated groups to pyridine groups was 1:1,implying that coordination-type interac tion occurred between the two kinds of groups, and each zinc ion coordinated with two nitro gen atoms in pyridine rings. The coordination strongly affected the solution behavior of Zn SIIR/PSVP blends. Viscosity increased rapidly as concentration of the blend increased. Un usual viscosity-temperature relationship was found for the blend solutions with low levels of polar cosolvent (hexanol).
    Ring-opening Polymerization of Lactones Catalyzed by Rare Earth Compounds(Ⅲ)──Bulk Polymerization of ε-Caprolactone with Neodymium Chloride-Epoxide System
    SHEN You-Qing, SHEN Zhi-Quan, SHEN Jian-Liang, ZHANG Fu-Yao, ZHANG Yi-Feng
    1995, 16(5):  820-822. 
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    Bulk polymerization of ε-caprolactone(CL) with neodymium chloride-epoxide sys tem has been studied. It was found that the addition of epoxide can greatly increase the catalytic activity of neodymium chloride. The catalytic activity sequence of NdCl3 combined with epoxide is: NdCl3-ethylene oxide > NdCl3-proplene oxide > NdCl3-epichlorohydrin≈NdCl3-allyl glycidyl ether. The catalytic activity of NdCl3-proplene oxide system increases,but molecular weight of resulting polycaprolactone(PCL) decreases at higher proplene oxide/ neodymium chloride molar ratio.The molecular weight of PCL can be controlled by catalyst concentration. Higher polymerization temperature can greatly increase the catalytic efficien cy. At 30℃, PCLwith molecular weight as high as 28. 9×104can be prepared easily with an activity of 44×104g PCLper molar neodymium, and at 60℃, the molecular weight of PCLand catalytic efficiency increased to 42×104and 106g PCL/mole Nd respectively.
    Crystalline Forms in Nascent Polyethylene
    WU Qing, ZHANG Qi-Xing, LU Ze-Jian, WANG Hai-Hua, OUYANG Wei, LIN Shang-An, ZHANG Guang-Hua
    1995, 16(5):  823-825. 
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    The crystalline structure of nascent polyethylene prepared by heterogeneous Ti-Mg catalyst has been studied.The reflection for the 001 planes in the monoclinic lattice from WAXD is more intense when the sample was synthesized at lower temperature, but remains constant for the samples at different polymerization yields. By treating the polyethylene powder by supersonic wave, a portion of the powder fell apart into smaller particles. Among the particles, a single crystal in monoclinic form was found by using TEM and electron diffraction.The generation of the monoclinic crystal is considered to be the presence of com pressive force in the polymerization process,which may arise from the crowding of the grow ing polymer globules.
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