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    24 March 1992, Volume 13 Issue 3
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    Articles
    Phase Transformation of Molecular Sieve VPI-5 into AlPO4-8 and the Relationship Between Both Frameworks
    XU Yi-hua, YAO Shang-qing, LIU Xin-sheng, PANG Wen-qin
    1992, 13(3):  281-283. 
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    The aluminophosphate molecular sieve VPI-5 has been received much attention as a new structure containing super-large open pores with 18 tetrahedral atoms.During the propcess of dehydration and desorption of water molecules in the channeles, the framework structure can be converted into AlPO4-8, which contains 14-membered ring open pores.The process of phase transformation was studied and the mechanism about the transformation is discussed.
    Studies on the Synthesis and Magnetic Exchange Interaction of Novel Heterogeneous Bridged Enolic Dicopper Complexes
    CHEN Jing-tang, LIAO Dai-zheng, ZHANG Ruo-hua, CHEN Hui, LU Jian-yi
    1992, 13(3):  284-287. 
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    Two dicopper complexes containing different exogenous bridges, Cu2(pfhmp)OH·2H2Oand Cu2(pfhmp)N3·H2O, were synthesized, where pfhmp3- denotes dehydrogen anion of N,N-diisonicotinoyl-2-hydroxy-4-methylisophthalaldehyde dihydrozone.Based on elemental analysis, IRand molar conductance, the complexes are proposed to have hetergeneous bridged structures and enolic configuration.The determination of variable-temperature magnetic susceptibility indicates that the variation of exogenous bridge obviously changes magnetic exchange interaction between two Cu(Ⅱ) ions.
    Studies on the Deuteration at the Chiral Nitrogen of Bis(tropolonato) (N, N, N' -Trimethyl ethyl enediamine) Cobalt (Ⅲ) Complexes
    MA Gui-lin, XU Yi-ming
    1992, 13(3):  288-291. 
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    Bis(tropolonato)(N,N,N'-trimethylethylenediamine) Cobalt(Ⅲ) complex, [Co(tp)2 (Me3en)]ClO4(Me3en = N,N,N' -trimethylethylenediamine, tp=univalent anion of tropolone), was synthesized.The complex was purified and separated into two racemic pairs (△(R) (S) and △(S) (R)-isomers) by the ion exchange method.The rate constants of deuteration(kD) at the chiral nitrogen were measured by high-resolution 1H NMRspectrometry.The value of kD at 34.0℃ was 1.0×105L·mol-1·s-1 for △(R) (S)-isomer and 1.8 × 104 L·mol-1·s-1 for △(S) (R)-isomer.The factors which influence the deuteration are also discussed in this paper.
    Preparation of Divalent Rare Earth Complexes with 3-Phenyl-5-(furyl-2)pyrazoline Dithioformate
    ZHANG Wei-guang, TANG Ning, GAN Xin-min, LIU Wei-sheng, TAN Min-yu
    1992, 13(3):  292-294. 
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    The new solid complexes of divalent rare earth with 3-phenyl-5-(furyl-2)pyrazoline dithioformate RE(SSCNC13HuNO)2·xH2O(RE= Sm, Eu, Yb, x=3,4) were prepared in Ar atmosphere.The composition and properties of the complexes as well as the differences between di- and trivalent rare earth complexes were studied on the basis of elemental analyses, IRspectra, electron spin resonance spectra, thermogravimetry, differential thermal analyses and the test for reducing property of the divalent rare earth complexes.
    Synthesis and Characterization of Hydroxyaluminosilicate Cross-Linked Montmorillonites with High Basal Spacings
    ZHAO Dong-yuan, WANG Gou-jia, YANG Ya-shu, GUO Xie-xian
    1992, 13(3):  295-299. 
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    A series of hydroxyaluminosilicate cross-linked montmorillonites (Al-Si-CLM) with high basal spacing(2.6 nm) were prepared by the method of collosol dispersed for the first time.The pillaring structuer, thermal stability and surface acidity of the pillared clays were studied by 27Al NMR.XRD, DTA, IR, XPS, TPD.The results show that the thermal stability of the pillared clays was not changed by doping silicate, and the surface acidity, especially the Brönsted acid, was greatly increased.The cracking of cumene was carried out in a pulse reaction system at 400℃ over the pillared clays.Doping silicate increased cracking activity of cumene.
    Synthesis and Characterization of the Solid Ternary Complexes of Rare Earths with L-Tyrosine and Glycine
    LIU Jing-xin, DUAN Li-mei, SUN Yuan-hong
    1992, 13(3):  300-302. 
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    The title complexes Ln(Tyr)(Gly)3Cl3·3H2O(Ln = La-Ho, except Pm) were synthesized.The mass spectra of gadolinium complex, in which the strongest peak (m/e=612) was assigned to [Gd155(Tyr)(NH2CH2COO)3·3H2O]+, further support the formation of the ternary complexes.In FTIRspectra, vas,COO- shifts to higher frequencies after the coordination (the heavy rare earth complexes shifted by 17～19 cm-1), but the shifting of vs,COO- is smaller.Two new absorption bands at 390 cm-1 (strong) and 443 cm-1(weak) are attributed to Ln-O and Ln-OH2 stretching vibration, respectively.These results indicate that the carboxylate ions coordinate to the rare earths as an unsymmetrical bridging bidentate ligand.
    Determination of Aluminum in Its Ternary Complex by Stop-Flow Kinetic Method
    YANG Yi, CAI Ru-xiu, HUANG Hou-ping, ZENG Yun-e, GAO Deng-yun
    1992, 13(3):  303-306. 
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    The kinetic characteristic of ternary complex, Al-3,5-dibromosalicylfluorone and surfactant, was studied with automatic kinetic analyzer.The reaction orders of the proton, color reagent, and surfactant were determined.The activation energy of the reaction was measured to be 29.58 kJ/mol.A simple, rapid, and accurate analytical method for the kinetic determination of aluminum was developed with a high sensitivity(ε=1.11×105L/mol·cm).The interference of many ions can be eliminated by kinetic method and it is satisfactory to apply this method to the determination of aluminum in the human hair samples.
    A Preliminary Study on Characteristics of Low-Power Microwave Plasma Torch Discharge
    LIU Xiao-jing, YU Ai-min, ZHANG Han-qi, JIN Qin-han
    1992, 13(3):  307-310. 
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    The characteristics of low-powered microwave plasma torch discharge are studied.The variation of excitation temperature with the observed height under different experimental conditions was measured by using double-line method.The emission intensities of Zri, Cd, Mg a-tomic and ionic lines were determined.The influence of experimental parameters on the excitation temperatures was also studied.The results show that the variations of emission intensities of analytes with observed height are in accordance with the excitation temperatures.They all have a maximum at the vertical height of 6～7 mm above the torch.The emission in the region of 5～10 mm above the torch is most intense, no matter for soft lines or hard lines.The emission profiles are not related to their excitation energies, but related to the optial structure of MPTdischarge.
    Studies on Fluorimetric Reaction of Salicyl aldehyde Isonicotinylhydrazone with Gallium
    CUI Wan-cang, TANG Bo, SHI Hui-ming
    1992, 13(3):  311-314. 
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    The fluorimetric reaction of salicylaldehyde isonicotinylhydrazone with gallium has been studied.The constants for dissociation of the reagent were established.The fluorescence excitation and emission wavelengths of the complex of gallium with the reagent are 395 nm and 480 nm, respectively.The sensitivity of the method is 4.0×10-4 ppm.The linear range is 0～1.0 μg/10 mL.The molar ratio of gallium to reagent was found to be 1:1.The proposed mathod has been used for the determination of trace gallium in geologic samples with satisfactory results.
    The General Equation of the Steady-State Voltammetric Curve at Ultramicrodisk Electrode——Mass Transfer Time Method
    WU Zhi-bin, ZHANG Zu-xun
    1992, 13(3):  315-319. 
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    In this paper, a new concept of mass transfer time is presented, by which the general equations of steady-state voltammetric curves simultaneously controlled by the Nernst diffusion, convection diffusion, charge transfer rate and chemical reaction at ultramicrodisk electrode are described.The behaviour of current-potential curve is discussed.
    Normal Dual Pulse Superimposed Four Potential Step Differential Voltammetry
    FANG Yu-zhi, WANG Ren-er, TONG Wei, HE Pin-gang
    1992, 13(3):  320-321. 
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    A new type normal dual pulse superimposed four potential step differential voltamme-try is proposed and realized on a microcomputer controlled voltammetric analyzer.The combination of differentiation and addition of samlping currents on four potential steps which are antisymmetric with each other respectively tends to offset the charging currents caused by forward and reverse potential steps.This new pulse technique has the merits of normal pulse voltammetry (NPV) and differential pulse voltammetry (DPV).At the same time, its rapid scan rate and short delaying time prior to current sampling make it more sensitive than DPVand suitable for the study of fast kinetics.
    The Determination of Stability Constants of Complexes of Zn(Ⅱ) and Cd(Ⅱ) with Amino-Acids, Dipeptides and Tripeptides by Micro-pH-Potentiometric Titration
    LU Ai-ru, Pettit L. D., Gregor J. E.
    1992, 13(3):  322-324. 
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    A potentiometric study on the complexes of His, Gly-His, Ala-His, Gly-Gly and Gly-Gly-Gly with Zn(Ⅱ), Cd(Ⅱ) is reported and small scale (piston buretle or microsyrine) potentiometric titrations were carried out to determine the stability constants of complexes at 25 ℃ and I = 0.10 mol/L (KNO3) conditions.The data treatment were performed with the computer program TITRE and SUPERQUAD on a BBCmicro-computer.The stisfactory results has been obtained by using this method.
    The Electrocatalytic Oxidation of Ascorbic Acid on Nickel Hexacyanoferrate Film Modified Electrode
    WANG Sheng-fu, JIANG Mian, ZHOU Xing-yao
    1992, 13(3):  325-327. 
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    The nickel hexacyanoferrate (NiHCF) film modified electrode was made by electrochemically depositing method.The electrocatalytic oxidation of ascorbic acid (AH2) on the electrode was described.The oxidation peak potential shifts negatively 300 mV.The modified electrode can be used for determination of ascorbic acid in the concentration range of 1.0× 10-7～1.0×10-2 mol/L.This method has been applied successfully to the analysis of ascorbic acid in fruits and vegetables.
    Syntheses and Coordination Properties of Bridged Bis(methimazole) Compounds
    LIU Qing-jian, SHI Ming-li, JIANG Chong-qiu, LIU Feng-ling
    1992, 13(3):  328-331. 
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    The syntheses and coordination properties of bridged bis(methimazole) compounds of Ia- IVa and Ib are studied.The UV spectra reveal that Ia- IVa coordinate UO2 (Ⅱ) (hard acid) ion into complexes with the ratio L:UO2(Ⅱ) = 3:1 and that Ib coordinates Hg(Ⅱ), Au (Ⅲ) (soft acid) ions into complexes with the ratio L:M = 2:1.The atomic net charge densities and frontier orbital (HOMO, LUMO) energies of Ia- IVa and Ib molecules were calculated by CNDO/2 method.
    Synthesis and Spectra Analysis of Triphenyltin-O,O- Diaryl dithiophosphates
    LI Jing, XIE Qing-lan, LUO Ning, ZHANG Dian-kun, HE Shui-ji
    1992, 13(3):  332-335. 
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    Triphenyltin-O, O-diaryldithiophosphates derivatives are a kind of organotin compounds with high biological activities.In this paper 13 triphenyltin-O, O-diaryldithiophosphates were synthesized.The IR, 1H NMR, 13C NMR, 119Sn NMR, MS and elemental analysis were determined.These results show that the structures of all compounds contain a four-coordinate tin atom.
    The Addition Reaction of Spirophosphoranes Containing P-H Bond (Ⅱ)
    LIU Lun-zu, LI Guo-wei, HUANG Ming-zhi
    1992, 13(3):  336-340. 
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    5-Hydro-1, 9-dioxa-4, 6-diaza-5-phosphaspiro[4, 4]nonane(1) reacted with carbon bisulfide or isothiocyanates at room temperature in the presence of excessive ethyl alcohol to give 2-mercaptothiazoline (2) and 2-substituted iminothiazolidines (4a) or aminothiazolines (4b) respectively.The mechanism of this reaction might involve that compound 1 reacted with ethyl alcohol via the exchange ester route to form a three coordinated phosphorous compound, which then added to the unsaturated bond.
    Studies on the Chemical Structure of Nephalsterol-B
    ZENG Long-mei, WANG Guiyang-shen, MA Li-bin, TU Guang-zhong
    1992, 13(3):  341-342. 
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    In the previous paper, a 19-hydroxylated sterol, nephalsterol-A.(1) was reported.This paper reports another 19-hydroxylated sterol, Nephalsterol-B(2) which was isolated from the same soft coral Nephthea tiexiexae verseveldt.2 is colorless needle crystals, m.p.159～161℃(EtOAc); m.p.160～162℃ (acetone), [a]D27+25°(C0.100, CH3OH).The structure of 2 is colorless crystals, m.p.159-161℃EtOAc) ; m.p.160～162℃.(acetone), [a]D27+25 was deduced as 24-methylene-cholest-5-ene-3p,7℃,19-triol mainly by 1H NMR, 13C NMR 1H-1H and 1H-13C COSY, ROESYspectra.
    Syntheses and Properties of New Lactam Type Open Chain Crown Ethers
    LU Guo-yuan, GE Yu-hua, WANG De-fen, HU Hong-wen, FENG Min, HUANG Jing, DAI Xiao-tian, LIU Chang-chun
    1992, 13(3):  343-345. 
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    Five new lactam type open chain crown ethers were prepared by the reaction of 2-methoxy-l-aminomethyl-naphthalene, benzyl amine and polyethylene glycolic acid dichloride respectively and identified by IR,1H NMR,MS spectrum.Calcium ion selective PVC membrane electrodes based on these compounds were prepared and electrode behaviours were evaluated.
    Applying Molecular Mechanics, Molecular Graphics and Quantum Chemical Methods to Study of Structure and Mechanism of Organic Reagent (Ⅰ)——Conformation of Chromogenic Reagent
    LAI Cheng-ming, YUAN Man-xue, TANG Jun
    1992, 13(3):  346-348. 
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    By means of molecular mechanics, molecular graphics and quantum chemical methods, the conformations of some chromogenic reagents such as par, 5-Br and 3,5-di-Br-PADAT, ECRetc have been studied, the rotational potential barrier has been calculated.
    Studies on the Circular Dichroism of Spin-Labeled Derivatives of Podophyllotoxin
    TIAN Xuan, LI Jing-xin, CHEN Yao-zu
    1992, 13(3):  349-351. 
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    The CD spectra of ten spin-labeled derivatives of podophyllotoxin were studied with CDrule of 1-aryl tetralin compounds and Snatzke's sphere rule.The relationship between the first couple and stereo-configuration and antitumor activity of these compounds were discussed.
    Asymmetric Synthesis of 2-(Bis-(2-Chloroethyl)-Amino)-5- Benzyloxytetrahydro-2H-1, 3,2-Oxazaphosphorine-2-Oxide
    CHEN Ru-yu, ZHANG Ming
    1992, 13(3):  352-354. 
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    A novel synthetic route of all enantiomers of 2-(bis-(2-chloroethyl)-amino)-5-benzy-loxy-tetrahydro-2H-1,3,2-oxazaphosphorine-2-oxide starting from the natural L-tartaric acid as a chiral synthon is described.The results relating to the structures of the intermediates and products in this synthesis are discussed.
    A New Sterol from the Marine Soft Coral Nephthea Sinulata
    LIU Ji-kai, ZENG Long-mei, WU Da-gang
    1992, 13(3):  355-357. 
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    The isolation of a new sterol, 24 (28)-methylene-cholest-5-ene-3β, 7β, 19-triol-7β-monoacetate(1), from the soft coral Nephthea sinulata is reported.The structure of 1 has been established by means of IR,1H NMR, 13C NMR, MS and elemental analysis.
    The Enumeration of Isomers of Hal omonoal kenes and Halomonoalkynes
    WANG Jian-ji, LIU Xin-hua, WANG Qiang, GU Fang-zhi
    1992, 13(3):  358-361. 
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    Polya theorem is used to find the generating functions of isomers of halomonoalkenes and halomonoalkynes; cis- and trans-isomerism and the isomers obtained by substitution of four kinds of halogen atoms are discussed.
    Effects of Lewis Base Ligands on Self-Assembling of Mo-Fe-S Cluster Complexes
    ZHANG Hong-tu, LIN Guo-dong, YANG Ru, SONG Yan, CAI Qi-rui
    1992, 13(3):  362-365. 
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    The effects of several neutral N-containing and P-containing ligands on the formation of Mo-Fe-Scubane-type clusters in MoS42--nFeCl2-DMF systems have been studied from the changes in electronic absorption-spectral characteristics and the probable mechanism was discussed.
    Studies on Thermodynamics of MX-NX2 and MX-NX3 Aqueous Electrolyte Solutions
    SHENTU Yan-ming, LI Yi-gui
    1992, 13(3):  366-370. 
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    The effects of the higher-order electrostatic terms on the thermodynamic properties of unsymmetrically mixed electrolytes with identical ion were investigated in the evaluation of the Pitzer mixing parameters, and the relationship between mixing parameter(θij) and ionic strength (I) was used in the evaluation.The Pitzer mixing parameters Sθij(0)、Sθij(1), and φijk were evaluated for MX-NX2 and MX-NX3 aqueous electrolyte solutions at 25℃.The calculation results are in good consistent with reference data.
    Studies on the Catalytic Activity, TPD and TPSR of CO over Supported Platinum Catalysts
    DU Shao-bin, WANG Jin
    1992, 13(3):  371-374. 
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    The catalytic activity for the oxidation of COon the supported Pt/MeM(Me = H, Cu, Ce) catalysts was investigated.CO-TPDon MeM and Pt/MeM was monitored by TC-GCtechnique.It was found that the peak temperatures of desorbed CO2 were in agreement with the catalytic activities.The results of TPSR(CO2) after a steady-state adsorption of COshow that the peak temperatures of the desorbed CO2 were lower than those of the desorbed CO2 of CO-TPD and the desorbed amount of CO2 and the order of peak temperature well agreed with their activities.Furthermore, the probable mechanism of oxidation of CO over Pt/MeM catalysts was also proposed.
    Interaction Between 2,2,3,3,4,4,4-Heptafluorobutanol and Anionic Surfactants
    DING Hui-jun, LIU Xu-hong, ZHAO Guo-xi
    1992, 13(3):  375-378. 
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    The mixed aqueous solution of C3F7CH2OH-C10 H21 SO4Na and C3F7CH2OH-C7H15 COONa was investigated by the surface tension analysis.When C3F7CH2OH is added into the anionic surfactants the surface activity of anionic surfactant is increased.In the surface layer the molecular interaction in the C3F7CH2OH-C10 H21SO4Na system is weaker (with smaller |βσ| value) than that in the C3F7CH2OH-C7F15COONa system; The counterion binding degree of C10H21SO4Na micelles increases with the concentration increase of C3F7CH2OH.
    Program Design for Electron Structure Calculation of Octahedral Transition Metal Complexes
    LI Xue-kui, SHEN Yi-min, LI Bo-fu, SUN Jia-zhong
    1992, 13(3):  379-381. 
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    A program for calculating electronic structures of octahedral transition metal complexes has been designed.It contains calculations of Hamiltonian matrix elements and some molecular parametres.
    Kinetic study on Axial Coordination Faster Reaction of Tetra(p-sulfophenyl) porphyrin Iron(Ⅲ)
    ZHU Zhi-ang, LIANG Xin-yi, LIU Heng-qian, CHEN Rong-ti
    1992, 13(3):  382-385. 
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    A kinetic study is reported for the axial coordination faster reaction of Tetra (p-sul-fophenyl) porphyrin iron (Ⅲ) (Fe(Ⅲ)TPPS4)D with ligands L [L=imidazole (Im)], 2-methylimidazole (MeIm), 2-ethyl-4-methylimidazole (EMIm)) in water by means of Union Giken RA-410 T-Jump spectrophotometer.
    Bonded-Tableau Calculation of the Potential Energy Surfaces of H3
    WU Wei, ZHANG Qian-er
    1992, 13(3):  386-389. 
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    The potential energy surfaces of H3 are calculated by using the self-consistent field method of bonded tableaux.The programs for the bonded tableau interaction and multibonded tableau self-consistent field and the calculations for H3 are implemented.The feature of bonded tableau method under some approximate conditions is discussed, and some suggestive conclusions for the application of valence bond method are obtained.
    Establishment of a Technique for Preparing Metal Single Crystal Electrode and Studies on Underpotential Deposition of Cu2+ on Pt(100), Pt(111) and Pt(110) Electrodes
    SUN Shi-gang, CHEN Ai-cheng, HUANG Tai-shan, LI Jing-bai
    1992, 13(3):  390-391. 
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    A technique for preparing metal single crytal electrode is developed and the set-up associated to this technique has been also established.The results of underpotential deposition (UPD) of Cu2+ on Pt(100), Pt(111) and Pt(110) electrodes prepared by the present technique demonstrate that the use of single crystal electrodes can deepen the knowledge of electrochemical processes of surface at an atomic level.
    Research on the Group Electronegativity(Ⅹ)——Group Electronegativity and Heats of Formation of X—SiRxH3-x
    HAN Chang-ri
    1992, 13(3):  392-394. 
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    This paper analyzes the relation between the standard heats of formation of XSiRxH3-x and the group electronegativity proposed by the author for group Xand builds up two methods for calculating the standard heats of formation of alkylsiliane derivatives.Besides, two formalas for calculating the dissociation energies of X—SiRxH3-x are suggested.
    Ab Initio Study of Two SN2 Reactions
    HUANG fu-hua, WANG Hao-bin, HUANG Ming-bao, SHI Yun-yu, WANG Cun-xin
    1992, 13(3):  395-397. 
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    We Performed ab initio calculations on two typical SN2 reactions (1), Fa- +CH3Fb→FaCH3+Fb-, and (2), Cla-+CH3Clb→ClaCH3 + Clb-, for their Minimum Energy ReactionPathways (MERP).It is found that for predicting the correct MERPs and reliable energetic results of these two reactions, the diffuse functions must be included in the selected basis set, and so corrected the errors in previously calculated activation energies for these reactions, especially for reaction (1).
    Studies on Model Potential Function and MNDO, MINDO/3 Method of Force Fields for Polyatomic Molecules
    CAO Ze-xing, SUN Ze-min, YAN Guo-sen
    1992, 13(3):  398-400. 
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    Based on previous papers, combining model potential function method with MNDO, MINDO/3 method, this paper suggests a new method of determining force fields for polyatomic molecules.The force constants obtained by this method are applied to calculating the vibrational frequencies of polyatomic molecules, resulting in a satisfactory outcome with a higher accuracy.
    Molecular Structure and Internal Rotation Barrier of Dibromocyanoacetamide
    WANG Yi-fei, LIANG Ying-qiu, YU Bai-heng
    1992, 13(3):  401-403. 
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    The crystals of 2, 2-dibromo-2-cyanoacetamide are monoclinic, space guoup P21/n, a=0.6223 nm, 6=1.1309 nm, c=0.9744 nm, β=96.84°, Z=4; R = 0.072 for 1834 reflections.The rotation barriers around O = C-Csingle bond of 2-cyanoacetamide and dibro-mocyanoacetamide are calculated by CNEXD/2 and INDO methods.
    Studies on Synthesis and Fluorescent Property of Aluminium Isopropyl Phthalate Acryloxyl Ethyl acetoacetate and Its Polymer
    ZHANG Yong-hua, ZHANG Wen-gong
    1992, 13(3):  404-406. 
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    Chelate compound aluminium isopropyl phthalate acryloxyl ethylacetoacetate (AIPAE) has been synthesized by the reaction of aluminium triisopropoxide with phthalic anhydride, ethylacetoacetate and acrylic acid.Chelate polymer PAIPAE has been synthesized by radical polymerization of AIPAE.The structures of AIPAE and PAIPAE have been determinated by elemental analyzer, ICP, IR, 1H NMR and 27Al NMR.Their fluorescent property in DMF has mainly been studied.
    The Trace of the Curing Process of Polyester/Mel amine Resins by FTIR
    LU Bao-tian, HE Chu-hua, SHENG Fen-ling
    1992, 13(3):  407-409. 
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    The curing process of polyester/melamine resins is investigated with FTIRin this paper.The peak at 913 cm-1 assigned to deformation of methoxy and the peak at 3500 cm-1 assigned to the stretching of hydroxyl were chosen as characteristic changes and the peak at 815 cm-1 assigned to the vibration (out-of-plane) of triazine was chosen as the internal sign in the curing process of polyester/melamine resins.The results show that the numbers of hydroxyl groups, methoxy groups and carboxyl groups are gradually reduced and the numbers of ether bonds and carbonyl groups are gradually increased along with the curing process, which indicates that the curing is a complex process of crosslinking accompanied by self-condensation and esteri-fication.The curing speed of polyester/melamine resins is related to [OH]/[OCH3] ratio.
    Complex-resins and Their Exchange Kinetic Properties
    ZHANG Yu-ge, WANG Bu-sen, ZHAO Shu-yan, HE Bing-lin
    1992, 13(3):  410-412. 
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    A new kind of ion exchange resin was prepared and the kinetic properties were tested.The exchange rate for methylene blue was faster than that of 001×7 resin, and the equilibrium utility of the functional groups of the new resin is two-fold higher than that of 001×7 resin.
    Synthesis of A-B Type Block Polymers by Group Transfer Polymerization
    XIA Hai-ping, DING Ma-tai, DING Jun-qi, LUO Hui-xiong
    1992, 13(3):  413-414. 
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    Several kinds of A-Btype block polymers with methacrylate, acrylate or acrylonitrile segments were prepared by means of group transfer polymerization and using dimethyl ketene methyl trimethylsilyl acetal as initiator and tetrabutyl ammonium bibenzoate as catalyst.The products were characterized by 1H NMR and FTIR.
    Structure of Chitosan Membrane and the Pervaporation of Ethanol/Water Mixtures by the Membrane
    LI Wen-jun, PAN Wen-sen, TANG Ying
    1992, 13(3):  415-417. 
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    The present paper covers the deacetylation degree and crystallinity of chitosan membrane, the effect of the feed composition and temperature on the permselectivity of ethanol/water mixtures permeated through the chitosan membrane.The results indicate that the permselectivity of the chitosan membrane is mainly affected by the free volume in the membrane.Both high separation factor and flux were observed when the chitosan membrane was neutralized with sulphuric acid.This behavior should be attributed to the hydrophilicity of the membrane and the ap-propritate free volume in the membrane caused by ion-crosslinking.
    Studies on Poly(n-butyl Acrylate)/Polyurethane Based on Castor Oil SEN (Ⅱ)——Full-SEN
    MA Rong-tang, MA Song, ZHANG Jun, TANG Xin-yi
    1992, 13(3):  418-420. 
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    Poly(N-butyl acrylate)/polyurethane based on castor oil (PnBA/COPU) full-SEN has been synthesized by simultaneous prepolymerization and the tensile, swelling and transition behavior, and morphology of full-SEN were characterized.The effect of composition on tensile strength, Young's modulus and elongation at break of full-SEN is similar to that of semi-SEN, but the values are higher than those of semi-SEN's as the weight fraction of PnBA is higher than 0.5.The micrographs of full-SEN show a two-phase morphology and the compatibility of the two components in full-SEN is much higher than semi-SEN.
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