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Table of Content

    24 September 1992, Volume 13 Issue 9
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    Articles
    Extraction of Citric Acid with Primary Amine N1923
    WANG Zhi-Hua, GAO Zi-Li, SUN Si-Xiu, SHEN Jing-Lan
    1992, 13(9):  1153-1156. 
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    The extraction of citric acid(H3A) from its aqueous solution with primary amine N1923(B) in kerosene was studied at 298±1K.The extraction equilibrum can be expressed as B(o)+iH3AB·iH3A (i=2/3;1).15%(V/V) high-carbon alcohol Al416(Chinese trade mark) was used as a modifier in organic phase.It was found that the probable component of the extracted complexes were B·(2/3)H3A and B·H3A which were confirmed by the mathods of isomolar series,saturatrion extraction,plot n/[H3A] versus [H3A] and the infrared spectra.The extraction capacity of inorganic acids and citric acid by N1923 is in the order of HCl HNO3HClO4>H3A.The possibility of stripping of citric acid from organic phase with aqueus solution containing hydrochloride is discussed.
    Studies on the System La(ClO4)3-(Glycme(Gly)-H2O(at 25℃)and Crystal Structure of Complex La(Gly)3(ClO4)3·2H2O in the System
    CHEN Jiu-Xiang, RAN Xin-Quan, GUO Zhi-Zhen, CHEN Yun-Sheng
    1992, 13(9):  1157-1160. 
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    The title system was studied,its equilibrium diagram was constructed by solubilities.There were two complexes La(Gly)3(ClO4)3·2H2O(I) and La(Gly)4(ClO4)3(II) occurring in the system.The incongruent complexes (I) was synthsized,its crystal structure was determined by X-ray diffraction,the structure of (I) consists of [La2(Gly)6(H2O)4]6+ cation and perchlotate ions.The crystal is triclinic with space group of P1 The unit cell parameters are as follows:a=1.0693(3) nm,b=1.25956(3) nm,c=0.8762 nm,a=82.83(3)°,β=67.25 (3)° γ=71.50(2)°,forming a distorted tricapped trigonal prism.
    Binuclear Complexes of Rare Earth with 1,10-Phenanthroline-N-oxide and Acetic Acid
    LIU Wei-Sheng, TAN Min-Yu
    1992, 13(9):  1161-1164. 
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    The binuclear complexes,hexa(1,10-phenanthroline-N-oxide)-bis(μ-acetato-O,O') bis (rare earth (Ⅲ)) perchlorate trihydrate(where,rare earth=Eu,Gd,Tb,Ho,Er,Yb),were synthesized and characterized by elementary analysis,molecular weights,molar conductances,IRspectra,electronic spectra,fluorescence spectra,TG and DSC measurements.
    Studies on the Structure of SAPO-5 Molecular Sieves
    ZHAO Da-Qing, PANG Wen-Qin, LI Li, YANG Guang-Di
    1992, 13(9):  1165-1167. 
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    The SAPO-5 single crystals with the size of 150μ×100μm crystallized in space group P6cc with a=1.3802 nm and c=0.8503 nm.The crystal structure was refined to Rw=0.043.F- anions are located on the wall of the framework between two four-membered rings.Electron probe microanalysis (EPMA) shows that silicon is only substituted for phosphorus.
    Studies on Complexes of Transition Metals with Schiff Bases(Ⅱ)——Studies on the Non-Isothermal Kinetics of Thermal Decomposition of Complex of Nickel (Ⅱ) with N-Salicylideneglycine Tripyridine
    SUN Hong-Jian, LI Xiao-Yan, GUI Xue-Gui, LIU De-Xin
    1992, 13(9):  1168-1170. 
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    The thermal decomposition of the complex of nickel (Ⅱ) with N-salicylideneglycine tripyridine and its kinetics were studied under the non-isothermal condition by TGand DTAtechniques.The non-isothermal kinetic data were analyzed by means of Achar method and Coats-Redfern method.The possible reaction mechanism was suggested by comparing the kinetic parameters.The results show that this thermal decomposition is a second-order chemical reaction.The kinetic equation can be expressed as:da/dt=Ae-E/RT·(1-α).The mathematics expression of the kinetic compensation effect is found to be:lnA=0.2738 E+0.7774.
    Studies on the Synthesis and Properties of FeAPO-44 Molecular Sieve
    LI Jun, WANG Xiu-Shan, BAI Yun-Shan
    1992, 13(9):  1171-1172. 
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    The FeAPO-44 molecular sieve was synthesized,hydrothermally in the presence of cy-elohexylamine used as the template.It was charaterized by X-ray diffraction patterns,electron scanning microscope,electron probe energy dispersion analysis.Thermal stability,adsorption property and catalytic property and so on were studied.
    Studies on the Solid State Reactions of Coordination Compounds (XLIX)——Solid State Synthesis and Crystal Structure of [(n-Bu)4N]3[Mo4S4Cl4]
    LI Ji-Guo, LANG Jian-Ping, XIN Xin-Quan, YU Kai-Bei
    1992, 13(9):  1173-1175. 
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    A violet red solid was obtained by heating the mixture of (NH4)2MoS4,AgCl and (n-Bu)4NBr in the solid state.The solid was extracted with CH2Cl2 to obtain a violet red cubic crystal [(M-Bu)4N]3[Mo4S4Cl4].The crystal belongs to the cubic system with space group F43C,a=b=c=2.4212(4) nm,Z=8.The anion core of the title compound can be viewed as a cube skeleton which is composed of four Mo atoms and four Satoms.The distance of Mo-Mo is 0.3154(8) nm.
    Performance Comparison Between Two Different Absorption Cells Used in MIP-AAS for Determination of Nickel
    DUAN Yi-Xiang, DU Zhao-Hui, HOU Ming-Yi, LIU Jun, JIN Qin-Han
    1992, 13(9):  1176-1179. 
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    A systematic performance comparison between two different absorption cells used in MIP-AAS for the determination of nickel is completed in this paper.Various factors,such as microwave forward power,carrier gas flow rate,the acidity of the sample solution,etc.,which affected the absorbance,were studied and compared with each other in detail.The effects caused by easily ionized elements and some concomitant elements were also examined for this purpose.A significant enhancement in sensitivity was observed in the determination of nickel when Ca,Mg or La existed.Some conclusions about the performance of T-shaped and L-shaped absorption cells were made
    Cupric Ion Transfer Across the Water/Nitrobenzene Interface Facilitated by lonophore ETH157
    QI De-Yao, XU Cheng-Min, YU Ze-Mu, WANG Er-Kang
    1992, 13(9):  1180-1183. 
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    The transfer process of cupric ion across the water/nitrobenzene interface facilitated by ETH157 has been studied by cyclic voltammetry.It has been concluded that the successive complex-formation between Cu2+ ion and ETH157 has occurred and coupled with adsorption phenomenon at the water/nitrobenzene interface.The mechanism of the transfer process is discussed.
    Reciprocal Oscillographic Chronopotentiometric Titration
    BI Shu-Ping, ZHENG Jian-Bin, WANG Qing-Feng, GAO Hong(H. Kao)
    1992, 13(9):  1184-1187. 
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    In this paper,a new method called reciprocal oscillographic chronopotentiometric titra-tion is presented.Because of its ability of decreasing charging current,the peak on (dE/dt)-1-E curve is more sharp than that of the corresponding incision on dE/dt-E curve and can be used to indicate the end-point of titration.
    Separation and Determination for Trace of Iron(Ⅲ),Cobalt(Ⅱ),Nickel(Ⅱ),Copper(Ⅱ) and Vanadium(Ⅴ) with 4-(2-BenzothiazolyIazo) Resorcinol by Reversed-Phase High-Performance Liquid Chromatography
    ZHANG Hua-Shan, SHI Zi-Dong, CHENG Jie-Ke
    1992, 13(9):  1188-1191. 
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    This paper reports the separation and determination of Fe(Ⅲ),Co(Ⅱ),Ni(Ⅱ),Cu (Ⅱ),and Ⅴ(Ⅴ) by reversed-phase HPLCwith 4-(2-benzothiazolylazo) resorcinol as a precol-umn derivatizing reagent.On C8 column,the five complexes can be separated quantitatively in the mobile phase of 68/32 (Ⅴ/Ⅴ) methanol/water system (containing2 mmol/Ltetrabutyiam-monium bromide(TBA·Br),pH 4.2 HAc-NaAc buffer solution.The detection limits are 2.5×10-1 ng for Cu,9×10-2 ng for V,1.3×10-1ng for Co,1.4×10-1 ng for Fe and 2.9×10-1 ng for Ni,respectively,when signal-to-noise ratio is 2.The method has been used in the analysis of reagent grade hydrochloric acid,and the results are satisfactory.
    Preparation of Film Modified Electrode by Electrochemical Method and Its Application for Anodic Stripping Voltammetric Determination of Pb(Ⅱ)
    ZHUANG Xiu-Run, XU Jin-Rui
    1992, 13(9):  1192-1195. 
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    In this paper we described the glassy carbon electrode treated by an electrochemical method in an aqueous solution containing the o-aminophenol,formaldehyde and sodium hydroxide.The sensitivity of the treated electrode for Pb2+ is about 60 times higher than that of untreated glassy carbon electrode.The electrode has a good reproducibility with a relative standard deviation of 3.7%(n=10).The anodic stripping peak height depends linearly on the Pb2+ concentration up to 10 ng/mL,and the quantitative limit with this electrode is 0.2 ng/mL.
    New Techniques of Reciprocal Oscillographic Chronopotentiometric Titration
    BI Shu-Ping, ZHENG Jian-Bin, WANG Qing-Feng, DU Si-Dan, GAO Hong(H. Kao)
    1992, 13(9):  1196-1198. 
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    New techniques of reciprocal oscillographic chronopotentiometric titration are presented in this paper.Equations of various "(dE/dt)-1-E" curves as well as the experimental results are given.
    Studies on Photochemical Fluorimetric Method(Ⅸ)——Determination of Menadione in Vitamin K3 Injection by in situ Photochemical Fluorimetry
    GUO Xiang-Qun, XU Jin-Gou, ZHAO Yi-Bing, CHEN Guo-Zhen
    1992, 13(9):  1199-1201. 
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    A method for determining menadione in vitamin K3 injection by in situ photochemical fluorimetry is reported in this paper.The effects of reaction medium,photon wavelength,oxygen,and irradiation time on the photoreduction reaction are also tested and discussed.Alinear curve is obtained over the rang of 0～9.60μg/mLmenadione (r=0.999) and the determination limit is 2.5 ng/mLfor menadione (w=11).The relative standard deviation is 2.7%.The a-mount of menadione in vitamin K3 injection determined by standard curve method and standard addition method is 94%～100% of marked amount.The recovery in standard addition test is 100%～107%.
    Synthesis and Crystal Structure of N-(2-Tosylamidoethyl)-monoazacrown Ethers
    QIN Sheng-Ying, ZHOU Zong-Hua, LIU Xue-Ming
    1992, 13(9):  1202-1205. 
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    N-Tosylethylenediamine reacted with appropriate polyglycol diiodide to give N-(2-to-sylamidoethyl)-monoaza-12-crown-4 (1) and-15-crown-5(2),but could not give-18-crown-6(3),which was obtained by the reaction of N-(2-tosylamidoethyl) diethanolamine (7) with tetraethyleneglycol ditosylate(8).The single crystal of 1 growing up from methanol solution belongs to monoclinic crystal system.The crystallographic data are;space group P21/a,a=1.4229(1) nm,b=0.9595(2) nm,c=1.4564(1) nm,β=102.20(1)°,V=1.9435 nm3,Z=4.The crystal structure was solved by the direct method in the packing of SDPstructure analyst-program.The refinement was carried out by the full-matrix least-square and the final Ris 0.043.The result shows the molecular configuration of 1,in which the ionizable tosylamide group was supported over the macrocyclic cavity by the ethylene group,is analogous to a desk lamp.
    Studies on Organophosphorus Compounds (LVII)——Radical Addition of Diphenyl (Diphenoxy) Phosphorus Chloride to Oximes——A New Synthetic Approach to-1-Aminoalkyl-Diphenylphosphine Oxides and Diphenyl-1-Aminoalkylphosphonates
    YUAN Cheng-Ye, QI You-Mao, CHEN Guo-Fei, ZHAO Cheng-Xue
    1992, 13(9):  1206-1211. 
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    The reaction of diphenyl(phenoxy) phosphorus chlorides with oximes in the presence of triethylamine in a perhalogenated solvent CFCl2CF2Cl can serve as a new synthetic approach to 1-aminoalkyl diphenyl phosphine oxides or diphenyl 1-aminoalkylphosphonates with good or excellent yields under mild conditions.Direct EPRobservations of radical intermediates Ph2＝O,PhCH＝N·originated from the homolytic scission of the unstable condensation product Ph2PON＝CHPh in the first stage,and the spin adduct of Ph2＝O to Ph2PON＝CH-Ph,has revealed the first example of radical addition of phosphorus reagents to  bonds.
    Studies on the Selectively Protecting Groups of Hydroxyls in Sucrose
    WU Hong-Qiao, LI Cui-Juan, WANG Shi-Yu
    1992, 13(9):  1212-1216. 
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    Reaction of sucrose with trialkyl orthoacetate,subsequent tritylation,acetylation,and detritylation afforded derivatives of sucrose acetate by selectively blocking specific hydroxyls in sucrose and 4-6 acetyl migration.The treatment of sucrose alkyl 4,6-orthoacetate hexaaeetate with water or alcohol in the presence of an acid catalyst afforded corresponding 2,3,6,1',3',4',6'-hepta-O-acetylsucrose and 2,3.1',3',4',6'-hexa-O-acetylsucrose.These derivatives of sucrose acetate were available from sucrochemical studies and have been developed as convenient intermediate for the synthesis of sucrose derivatives.
    Studies on the Synthesis and Biological Activity of N-Aryl-N'-(5-Aryl-2-Furoyl )Thiourea Derivatives
    WEI Tai-Bao, CHEN Ji-Chou, WANG Xiu-Chun, YANG Su-You
    1992, 13(9):  1217-1221. 
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    In this paper,forty new N-aryl-N'-(5-aryl-2-furoyl)thiourea derivatives were synthesized under the condition of solid-liquid phase transfer catalysis,the compositions and structures of which were confirmed by elemental analysis,UV,IR,and 1H NMR spectroscopic measurements.Compared with classical methods,this one has the advantages of simple operation,mild conditions and high yields.The promoting effects of these new compounds on wheat growth were tested preliminary.
    Synthesis and Herbicidal Activity of S-(N-Substituted Carbamino methylene)-O,O-Dialkyl Phosphorodithioate
    YANG Hua-Zheng, LI Xiao-Lei, ZHANG Zheng-Pu, CHENG Mu-Ru
    1992, 13(9):  1222-1226. 
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    In acetone or chloroform/water,a series of S-(N-substituted carbaminomethylene)-O,O-dialkyl phosphorodithioates were prepared by the reaction of ammonium O,O-dialkyl phos-phorodithioate with α-haloalkanoamide,the substituent effect of which was studied.All of the compounds were confirmed by elemental analysis,IR,1H NMR and MS.The results from the preliminary herbicidal tests show that introducing dithiophosphoryl group the herbicidal potency of the compounds were not only the same as that of a-chloroacetamide,but also their selectivity increased for the broadleaved plants.The relationship between chemical structure and activity was discussed.
    Studies on Metal-Metal Bonded Organic Compounds——Synthesis of Bis[η5-Substituted Cyclopenta-dienyltricarbonylmolybdenum(tungsten)]Dimer
    SONG Li-Cheng, SHEN Jin-Yu
    1992, 13(9):  1227-1230. 
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    Through the reaction of Fe2(SO4)3/HOAc aqueous solution with sodium or lithium η5-substituted cyclopentadienyltricarbonylmolybdenate (tungstate) salts (η5-RC6H4) (CO)3MNa (Li),nine bis[η5-substituted cyclopentadienyltricarbonyimolybdenum (tungsten)] dimers [(η5-RC5H4 (CO)3M]2(M=Mo,R=C(O)Me,CO2Me,CO2Et,Me3Si,n-Bu;M=W,R=C(O)Me,CO2Me,CO2Et,n-Bu) were prepared and their structures were characterized by C/H analysis,IR,1H NMR and MS techniques.
    Application of Electrochemical Synthesis by Using Sacrificial Metal Anode(Ⅰ)——Reductive Coupling of Carbonyl Compounds
    XIAO Ya-Ping, BEI Mei-Zhi
    1992, 13(9):  1231-1232. 
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    Electroreduction of carbonyl compounds has been investigated by using sacrificial magnesium anode.The reduction products of both aldehyde and ketone were in moderate yield.The reaction process via radical anion intermediate then coupling to the products was discussed.
    Studies on the Battery of Vulcanized Poly acetylene
    XIE De-Min, FU Yu-Jie, WANG Rong-Shun, WANG Cun-Guo, ZHANG Xi-Yan
    1992, 13(9):  1233-1237. 
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    The rechargeable battery was prepared from a cathode-active substance of vulcanized polyacetylene,an anode disk of Li and an electrolyte consisting of a dioxolane with 2 mol/L LiClO4.The properties of battery were studied.The results of experiment indicate that the battery has a quite high energy of 1500～2000 W·h/kg,which were calculated according to the cathode-active substantial amount.
    Electronic Structures and Nonlinear Third-Order Optical Properties of Ni-Porphyrin
    FENG Ji-Kang, GAO Xu-Ling, SUN Jia-Zhong
    1992, 13(9):  1238-1240. 
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    The electronic structure UVspectrum and nonlinear third-order optical susceptibility γof Ni-porphyrin were studied.It can be concluded that in this compound the contribution of Ni2+ ion to γis very littles the contribution of porphyrin ring to γ is the dominant one and the nonlinear third-order optical susceptibility will increase exponentially with the increase of the number of conjugated bonds of ligands in the complex.
    N-representability Problem in the Reduced Density Matrix
    JIANG Xiao-Qin, JIANG Mao-Sen, LI Bo-Fu, SUN Chia-Chun
    1992, 13(9):  1241-1244. 
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    By means of the basis functions with quasispin-symplectic symmetry and the method of constructing expose operator proved by Kummer,the extreme point problem of the N-repre-sentability theory of the reduced density matrix in quantum chemistry is studied Furthermore,on the basis of the former works,some more extreme points of the convex set of the second reduced density matrix are discovered.
    Studies on Relaxation Kinetics of Coordination Reaction Between Yttrium and 2-(4'-Chloro-2'-phosphono-phenyIazo)-7-(2',6'-dibromo-4'-chloro-phenylazo)-1,8-dihydroxy-3,6-naphthalene Disulfonic Acid
    AN Cong-Jun, FANG Xian-An, LIN Zhi-Xin, ZENG Fu-Sheng
    1992, 13(9):  1245-1248. 
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    In this paper,the relaxation time was determined at different temperatures by the concentration jump relaxation method.The expression of l/t was derived from the assumed mechanism of reaction.The apparent rate constant and molecular absorbance index were obtained by the concentration-jump relaxation method.The arrhemus activation energy is 52.82 kJ/mol and the activation enthalpy is 50.43 kJ/mol.The activation entropy is a negative in the range of 278～K298 K.The stability constant of complex is 13.84.These experimental results are in agreement with those obtained by using other methods.
    Catalytic Behaviour of Synthetic Saponites and Their Pillared Analogues During the Disproportionation Reaction of 1,2,4-TrMB
    ZHOU Qun, HUANG Dong-La, WANG Cai-Xia, JIANG Da-Zhen, MIN En-Zhe
    1992, 13(9):  1249-1252. 
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    The pillared saponite elays(PS) were prepared by cross-linking the saponitc with aluminium hydrxy polymer [Al11O4(OH)24·(H2O)12]3+ The catalytic properties of saponite and their pillared analogues were investigated during the disproportionation reaction of 1,2,4-trimethylbenzene.Te results show that the catalytic activity increases with increasing the acidic amount on the surface of PSand the percent of 1,2,4,5-Te MB in Te MB and of o-xylene in xy-lene are higher than their values of thermodynamic equilibrium respectively.The catalytic property which is related to the pillar density in the PS
    A Transitlon State Calculation Method with Electronic Correlation
    HE Li-Ming, NI Min, JIN Qian-Yuan, LIU Hong-Lin
    1992, 13(9):  1253-1256. 
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    A new transition-state calculation method based on the X.theory is presented,which includes the correlation effect with electronic self-interaction correction.Ionization potentials of atoms were calculated.The numerical results from the calculations indicate that correlation energy has a great influence on the ionization potential and the values of which are from-0.41 eVto 0.94 eV,The calculated results combmig the correlation effect are quite good.This new scheme has the advantage of simplicity and reasonableness,and can be applied to molecular calculation.
    Luminescence and Energy Transfer of Ce3+, Mn2+ in Ca2B2O5
    CHANG Shu-Lan, GUO Feng-Yu, SUN Yin-Guan
    1992, 13(9):  1257-1259. 
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    The dependence of photoluminescent properties of Ce3+ and Mn2+ in Ca2B2O5 on their contents was studied.The mechanism of energy transfer from Ce3+ to Mn2+ is also discussed.
    The Relationship Between Dipole Moment of the Single Solvent for Formic Acid, Acetic Acid and Water and Concentration of Salt
    LI Xi, XU Qin-Tang, JIANG Fu-Ming, LIU Xiao-Jiang
    1992, 13(9):  1260-1262. 
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    The salt effect of dipole moment was measured by the small capacity condenser for formic acid-calcium chloride,acetic acid-calcium chloride and water-calcium chloride.It is found that the apparent dipole moment or salt effect-dipole moment changed due to the salt effect in the single solvent-salt solutions.Because of the change of salt concentration,the dipole moment diverges from the values in the pure solvent.
    Studies on Synthesis of n-Butyl Acetate Using Tungstophosphorous Heteropoly Acid as a Catalyst
    ZHAO Ning, GONG Lin-Fei, LI Jun-Qi
    1992, 13(9):  1263-1264. 
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    We studied systematically the conditions of the synthesis of n-butyl acetate using tungstophosphorous heteropoly acid in place of suifuric acid as the catalyst in this paper.The experiment of intermittent esterification shows that 12-tungstophosphorous acid can give a good selectivity,activity and high productivity.The probable reaction mechanism of HPW in the esterification is also presentted.
    Investigation on the Preparation of Ultrafine Particle Iron-carbonide Catalyst for F-T Synthesis
    ZHANG Jing-Chang, ZHAO Hong, CHEN Qi-Bin, GAO Xiao-Yun, GUO Guang-Sheng, WANG Wei-Jie, YANG Fu-Ming
    1992, 13(9):  1265-1267. 
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    A preparation method of Fe3Cultrafine particle catalyst,from highly dispersed amorphous Fe powder and free carbon by laser pyrolysis technique,was investigated.The catalytical reactive species,α-Fe,and iron carbonide catalyst for F-T synthesis were obtained directly.The catalyst obtained under different experimental conditions was characterized by XRD,electronic diffraction and TEM techniques.The influences of preparation condition on the crystalline grain size,crystal shape of the catalyst obtained and the component of iron carbonide in the catalyst,are also disscused.
    The Approach to Quantification and Estimation of the Lewis Acidity and Basicity of Benzene and Its Derivatives
    WANG Xiao-Jiang, WANG Lian-Sheng, ZHANG Zhu-Qing
    1992, 13(9):  1268-1270. 
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    A new approach to the quantification of the Lewis acidity and basicity of benzene and its derivatives was presented in this paper.The logarithm difference values of partition coefficients of the compounds in butyl ether/water and in cyclohexane/water system were used as the measurement of the acidity,while the logarithm difference values of the partition coefficients in trichloromethane/water and tetrachloromethane/water systems were used as the measurement of the basicity.The experimental results show a good correlation with the values in literatures.In addition,an estimation method for basicity was also developed.
    Specific Recognition of Interresidue and interpeptide in Proteins
    WANG Yu-Hong, LIU Xiao-Qing, LI Wei, MA Su-Cheng
    1992, 13(9):  1271-1274. 
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    We extracted 524 pairs of parallel peptide segments and 2283 pairs of anti-parallel pep-tide segments of 5 residues long from the 125 heterogeneous proteins,and then applied the statistical analysis algorithm to calculating residue-residue pairing frequencies.Finally the relative pairing frequencies or affinities were obtained.From the affinities it can be seen that there exists substantially specific residue-reside pairing between two strands of the interactive peptide segments.The obtained results will be helpful for protein engineering and structure prediction.
    Fluorescence Spectra of Sulfomethylated Phenolic Resin Excimer
    ZHUANG Yin-Feng, YANG Bao-Cheng
    1992, 13(9):  1275-1277. 
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    Fluorescence spectra of sulfomethylated phenolic resin (SMP) in pure water and aqueous solutions containing the added salt have been investigated in this paper.The spectra confirm the formation of the intermolecular excimer of polyelectrolyte SMP,in which the chro-mogenic groups are on the main chains.It is possible to use the intermolecular excimer of SMPas a probe to study the molecular morphological changes of SMP.
    The PTC Effect of Carbon Black Filled Vinyl Polymer
    PIAO Jian-Hui, TANG Hao, YANG Hua-Li, CHEN Xin-Fang, LUO Yun-Xia, LI Shu-Hua
    1992, 13(9):  1278-1281. 
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    In this paper,the mechanism of positive temperature coefficient (PTC) effect is investigated by using carbon black filled low density polyethylene and ethylene-vinyl acetate copoly-mer.The influence of carbon black content on the resistivity at room temperature and PTCeffect as well as the influence of crosslinking on electrical reproducibility are also discussed.
    A Study of Polymerization of THF with CH3COBF4 as Catalyst
    LI Fang-Xing, CAO Xiu-Lan, HUANG Chang-Hua, LI Chun-Gang, LI Jie-Tao, LI Chun-Rong, ZHU Duan-Hui, YANG Jun-Yan, HUANG Jia-Xian
    1992, 13(9):  1282-1285. 
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    In this paper,a synthetic method of PTHF was introduced with CH3COBF4 as catalyst and the mechanism and kinetic behaviour of polymerization of THF were discussed in detail.The polymerization temperature has a great influence on the polymerization rate constants.The apparent rate constants of polymerization are 1.18,2.35 and 6.07×10-3 L·mol-1·s-1 respectively at 0,6 and 15℃ and the apparent active energy is 71.68 kJ/mol.
    Preparation and Crossl inking of Aerylate Copolymer Latex Containing Carboxyls/Epoxy Resin——Ⅰ.Molecular Design and Preparation of Acrylate Copolymer Latex Containing Carboxyls
    LIU Shu-Xia, YU Ding-Sheng, JIAO Shu-Ke
    1992, 13(9):  1286-1289. 
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    The purpose of the article is try to carry out the crosslinking reaction of acrylate copolymer latex containing carboxyls/epoxy resin.According to the molecular design,the composition of the copolymer was first calculated and the synthetic method of latex was studied.With the help of 1H NMR and acid-base titration,the number of carboxyl group in the copolymer and on the surface of latex particles was determined,the film forming characteristics of latex with different monomer ratio was also compared.
    Studies on Mechanism of GTP Activated by Ionic Field
    DING Ma-Tai, XIA Hai-Ping
    1992, 13(9):  1290-1292. 
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    On the basis of former studies found in literatures,the mechanism of group transfer polymerization (GTP) activated by ionic field was proposed.In this mechanism,initiator is activated by a special ionic field produced by anionic catalyst.The intensity of the field enjoyed by each molecule of imtiator(Qi) is directly proportional to total intensity of the field (Q) which is directly proportional to the equivalent concentration of catalyst,and is inversely proportional to the equivalent concentration of initiator (n),i.e.Qi=Q/n.Along as Qi reach a certain value,i.e.Qi≥Qmm,GTP will take place.Along with the raise of Qi value,activation extent of initiator increases,induction period of polymerization shortens,and the speed of polymerization increases.
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