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Table of Content

    24 June 1992, Volume 13 Issue 6
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    Articles
    Studies on the Synthesis of Molecular Sieves from TMAOH-P2O5-Al2O3-SiO2-H2O-HF System
    ZHAO Da-qing, QIU Shi-lun, PANG Wen-qin, ZHANG Jian-guo, WU Yi-jie, PEI Feng-kui
    1992, 13(6):  717-719. 
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    The zeolite Pcontaining phosphorus and SAPO-20 molecular sieve were synthesized by hydrothermal crystallization with H3PO4, boehmite and colloidal silica in the presence of HF and TMAOH as the template.The crystallization fields of the two molecular sieves were obtained by changing the contents of P, Al and Si in the reactants.The ways of heteroatom substitution were investigated by 31P and 29Si MAS NMR technique.
    Synthesis, Properties and Structure of the Ionic Association Complexes of Rare Earth Nitrates with Cyclam
    YANG Ru-dong, YAN Lan, WANG Qi-guang, LIU Jian-min, ZHANG Yun
    1992, 13(6):  720-723. 
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    The ionic association complexes of La-Tb and Yions with Cyclam were synthesized from the acidic medium of methanol aqueous solution.Through the investigation of elemental analysis, IR,1H NMR and DTA-TGwe propose that the complexes have a general formula L+L2+0.7[Ln(NO3)6]0.8[Ln(NO3)3·3H2O]0.2·nH2O(where Ln=La-Tb and Y; n=3 for La and Ce; n=2.5 for Pr-Tb and Y, L=Cyclam).The structure of L+L2+0.7[Nd(NO3)6]0.8[Nd(NO3)3·3H2O]0.2·2.5H2O was determined by single crystal X-ray diffraction analysis.The lattice parameter are as follows; space group R3, a=1.7000(1) nm, b=1.7000(1) nm, c=1.9862(4) nm, α=90°, β=90°, γ=120°, Dc=1.703 g/cm3,μ(Ka)= 132.9 cm-1.
    Synthesis and Crystal Structure of [Bu4N]2[W2Ag3S8(C6H5CSS)] with Dithiobenzoic Acid as the Ligand
    JIN Xiang-lin, NI Hai-hong, TANG Ka-luo, TANG You-qi
    1992, 13(6):  724-726. 
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    The title compound was prepared from the reaction of (NH4)2WS4, AgNO3, (Bu4N)+(C6H5CSS)- and Bu4NBr in CH3CN solution, then crystalized in CH3CN/MeOH.It crystalizes in monoclinic space group P21/c with the following crystal parameters, a =1.8945 (12) nm, b=1.1963(10) nm, c=2.5660(14)nm, β=98.13(5)°, V=5.757(6) nm3, Dc=1.830 g/cm3, Z=4.The final R=0.0827 for 3329 reflections.The W2Ag3 unit in the anion W2Ag3S8(C6H5CSS) forms a five-membered ring.
    The Synthesis and Crystal Structure of Manganese (Ⅲ) Hydroxyaquotetrakis (4- trimethyl aniline) porphyrin Triiodide Chloride Hydrate
    ZHENG Guo-dong, AN Qing-da, WANG Tao, WANG Feng-shan, CAO Xi-zhang
    1992, 13(6):  727-731. 
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    The title compound([Mn(Ⅲ)OH·H2O-TMAP]·I3·Cl·9H2O) was synthesized and characterized by X-ray diffraction method.The crystal belongs to monoclinic system, space group P21/a with a= 1.8502(1) nrn, 6=1.2138(1) nm, c=3.0459(2) nm, β=104.52(4)°, Z=4, V=6.9513 nm3, Dc=1.492 g·cm-3, R=0.096, Rw=0.087.The two oxygen atoms coordinated to manganese(Ⅲ) were determined by recognizing central manganese valence with ESRand Spectroelectrochemistry.The stable manganese valence of the coordination was discussed.
    Selective Reduction Decomposition of Peroxotungstate by SO2 in Acidic Solution——Removing Trace Molybdenum from Tungsten
    WANG Zhi-hong, JIANG An-ren, GU Chun-lin
    1992, 13(6):  732-734. 
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    Complex-Homogeneous Precipitation Method was developed for precipitation of tungstic acid at room temperature and low acidity.This method can also be used to remove trace molybdenum from tungsten by selective reduction decomposition when SO2 is introduced to the mixed solution.The linear relationship between peroxotungstate and peroxomolybdate concentration in solution was established, i e. ln=[W]=kln[Mo]+A which A=ln[W]0 - kln[Mo]0.The separation constant k becomes large when temperature and acidic strength rise and their relationship is k rises slightly with the increase of [H+]2(from [H+]=0.5 to 4.0 mol/L) and exp (-1/T) (T=273 +t , 20≤t≤50℃).The kinetics mechanism was also discussed.
    Synthesis and Identification of Undecatungstozirconates with a Transition Metal
    WANG Wei, ZHU Xiu-hua, LIU Jing-fu
    1992, 13(6):  735-736. 
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    The Kn[MZrW11O39]·xH2O(M=a metal from the first-row transition metals) were synthesized and identified by IR, UV, TG-DTA, XPS and Chemical analysis etc.
    Investigations on Polarography with Linearly Changing Potential (ⅩⅪ)——On the General Theory for The Convolution and Deconvolution Adsorptive Complex Wave
    CHEN Qiao, ZHANG Zu-xun
    1992, 13(6):  737-740. 
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    The present paper covers the general equation of convolution and deconvolution ad-sorptive complex wave and the behaviour of current-potential curve.Experimental results are in good agreement with the theoretical ones.
    Application of Reflectance Thin-layer Spectroelectrochemical Method
    ZOU Ming-zhu, SHENG Gui-hua, ZHENG Yan-sheng
    1992, 13(6):  741-744. 
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    With ferrocene and methylene blue in nonaqueous solvents, we tested the characteristic of the reflectance thin-layer spectroelectrochcmical cell which was designed by ourselves.We observed a very good response of optical signal to electrosignal.We determined the E0' and n values of ferrocene and the diffusion coefficients of potassium ferrocyanide and methylene blue.The mechanism of methylene blue being reduced in DMSOmedium was investigated.
    Quantum Chemistry Calculation for the π-Charge Density Distribution of 2,3,7-Trihydroxyfluorones and the Discussion of Their Properties
    WU Nian-ci, LIU Ding-wu, WANG Nai-dong, QI Wen-bin
    1992, 13(6):  745-748. 
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    The π-charge density distribution of fifteen 2,3, 7-trihydroxyfluorones has been calculated by HMO method.The sequence of the dissociation of three hydroxyl groups of 1,3,7-tri-hydroxyfluorones has been settled by analysis of π-charge density distribution.According to the proper acidity ranges of color reactions and the molar ratio of the colored complexes, the structure of the complexes are discussed.
    Catalytic Reaction-Oscillopolarographic Method for the Determination of Trace Amounts of Nitrite——Studies on the Catalytic System of NO2--BrO3--Methyl Red
    JIANG Zhi-liang, LIANG Ai-hui, DAI Guo-zhong
    1992, 13(6):  749-751. 
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    The present paper covers a novel and highly sensitive catalytic method for the determination of nitrite as low as 0.1 ng/mL, It is based on the fact that the nitrite ion catalyses the slow redox reaction between methyl red and BrO3- in 0.016 mol/L H2SO4 at 100℃.Cooling by tap water was chosen to quench the reaction.And oscillopolarography was used as detection technique for methyl red in NaOHmedium which exhibits a sensitive oscillopolarographic wave at -0.56 Vvs.SCE.Nitrite in water samples was analysed by this method with excellent results.
    Preparation and Separated Mechanism of Glass Capillary Column with Dicarboxyl Crown Ether Stationary Phase
    ZENG Zhao-rui, WANG Chun-nuan, WU Cai-ying, HUANG Zai-fu, WANG Yu-ting
    1992, 13(6):  752-755. 
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    The present paper covers a new method for the preparation of glass capillary columns with dicarboxyl crown ether stationary phase and their chromatographic characteristics, including column efficiency, phase transition temperature, thermal stability, polarity and selectivity.It is shown that they have good chromatographic characteristics and unique selectivity in the separation of some polar position isomers.The reaction mechanism and the factors which affect the separated mechanism are discussed.
    Studies on Potentiometric Titration System of Precipitation of Aluminium-Fluoride in Ethanol-Water Midium
    LI Xi-chun, ZENG Bin-li
    1992, 13(6):  756-758. 
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    The present paper covers the chemical equilibriums of precipitation of aluminium with fluoride in ethanol-water midium.The successive stability constants for aluminium-fluoride were determined in the complexation domain of the titration curve.The solubility product of the precipitation of Na3AlF6 was calculated in precipitation domain of the titration curve.The effect of pH on the equilibrium was theoretically investigated.The additional proton constants of fluoride ion were determined in water and ethanol midium with different concentrations.The values are found to be in fair agreement with literature data.The titration system was tested by standard recovery and standard sample analysis.Recovery ratio is 100±0.6%.The relative errors for standard sample analysis are less than 1%.It is shown that the system for aluminium-fluoride potentiometric titration is valid.
    Studies on Trace Organomercury Speciation by RP-HPLC
    JIANG Shuang-ying, LIU Jin-chun, LIU Liang-bin, CHENG Jie-ke
    1992, 13(6):  759-761. 
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    With precolumn derivatization by Bismuthiol Ⅱ , MeHg+, EtHg+ and PhHg+ were quantitatively separated and determined by RP-HPLCon a Shimadzu CLC-C8 column.Abu-tanol-methanol-water mixture was used as the mobile phase, and malic acid was chosen as an auxiliary complexant.The detection limits are 1.4 ng(MeHg+), 1.0 ng(EtHg+) and 2.5 ng (PhHg+), respectively.The method was applied to speciation analysis of organomercury in environmental water.
    The Mass Spectra Study of the N,N'-Bis(2-Hydroxyl- benzylidene)-1, 1-Diaminoalkanes
    ZHAO Tao-nan, JIANG Yan-hao, YANG Ji-hong, BAO Yan-chu, BU Xiu-ren, YOU Xiao-zeng, MENG Qing-jin
    1992, 13(6):  762-766. 
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    The electron impact mass spectra of the series of title compounds, double Schiff base, has been studied.Owing to the common parent molecular structure, they undergo certain subsequence cleavage paths.All of these cleavages were discussed in detail.Among which the most interesting one was the cleavage, from molecule (OE+) ion to an OE+ fragment ion, in which several processes concomitantly took place with r-Hrearrangement, electron transfer, double bond migration and ion reconstruction.The evidences of the mentioned cleavages were investigated by monitoring the product ions via experiments of high resolution MS, isotopic exchanging operation, link scan technology and coilission induced dissociation (CID).
    Studies on the Components of Sanguisorba Officinalic L.
    LIU Xiang-qian, JIA Zhong-jian, LIU Zi-min
    1992, 13(6):  767-769. 
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    Seven compounds (Ⅰ, Ⅱ, Ⅲ, Ⅳ,Ⅴ,Ⅵ,Ⅶ) were isolated from the extract of 80% aqueous ethanol of the roots of Sanguisorba officinalic L.by means of silica gel column and prepared thin layer chromatography.Their structures are elucidated on the basis of chemical and spectral analysis(IR, MS, NMR, UVand elemental analysis), and the comparison with authentic samples and references.They are 2,4-dihydroxy-6-methoxyacetophenone(Ⅰ), 3,3',4-tri (O-methyl)ellagic acid (Ⅱ), 3,4,4'-tri(O-methyl)ellagic acid (Ⅲ), Sanguisorbigenin (Ⅳ), Ziyu-glycoside Ⅰ (Ⅴ), Ziyu-glycoside Ⅱ (Ⅵ) and β-sitosterol-β-D-glucoside (Ⅶ).Among them, Ⅰ is found for the first time from Nature and Ⅲ is a new compound.
    The Synthesis of 1,1' -Diselena Substituted Ferrocene Derivatives
    LI Pu, SHI Shu-jian
    1992, 13(6):  770-773. 
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    In this paper, an improved method for the synthesis of 1,1'-diselena substituted ferrocene derivatives is given.It involves the reduction of 1, 2, 3-triselena[3]ferrocenophane by LiAlH4 to form ferrocene 1,1'-diselenol, followed by the addition of an electrophile and triethy-lamine to the above reaction mixture to produce the title compounds in situ.Twelve such compounds were obtained, among which seven are new selenium-containing ferrocene derivatives.The structure of the products was identified by elemental analysis and 1H NMRspectrum.Abrief discussion on the relationship between the 1H and 77Se NMR spectra and the structure is given.
    Synthesis of Substituted Phenyl Perfluoroalkyl Ketones
    GONG Yue-fa, MA Yan-long, QU Yan-ling, ZHAO Cheng-xue
    1992, 13(6):  774-777. 
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    By the reactions between substituted phenylmagnesium halides and perfluorocarboxylic acids in tetrahydrofuran, nine substituted phenyl perfluoroalkyl ketones (1～9) were synthesized and characterized by IR, UV, 1H NMR, 19F NMR and MS.The ketones 6, 7, 8 and 9 are new and useful fluorinated compounds.
    Synthesis and Properties of Oil Soluble Azo Dyes
    PENG Xiao-jun, WANG Ji-tao, YANG Jin-zong
    1992, 13(6):  778-780. 
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    The oil solubility of dyes is demanded by many aspects of modern technology.Six novel oil soluble azo dyes are studied with focus on the synthesis and the relationship between oil solubility and molecular structure.The decisive factor of high oil solubility is the presence of a substituent with a large bulk in the ortho position of the azo group in the dyes'molecule.
    Studies on Chemical Constituents of Senecio Nemorensis L.
    CHENG Dong-Hang, GAO Jian-jun, YANG Li
    1992, 13(6):  781-783. 
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    A new sesquiterpene was obtained from the ethanol extract of the whole plant of Sertecio Nemorensis L.by silic gel column chromatography.Its structure is established as la, 10β-dihydroxy-6β-angeloyloxy-9-oxo-furanoeremophylane by means of IR, UV, MS, 1H NMR, 13C NMR, DEPT and two known sesquiterpenes were isolated as well.
    Investigation on Chemical Bond for Interstitial Compounds of Rare-Earth Element Tetrahedral Cluster R4OC16
    LIN Meng-hai, CHEN Ming-dan, ZHANG Qian-er
    1992, 13(6):  784-786. 
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    Four systems Sm4OCl6, Eu4OCl6, Yb4OCl6 and Gd6N2Cl12 were calculated by using SCC-DV-Xa method.It is found that the interstitial atom plays a determinative role in syntheses of tetrahedral cluster.There are six skeleton orbitals in the compound, three of them are formed from the interstitial atom oxygen and the rare-earth atoms, and the others are bonded by the 4f orbitals of the rare-earth atoms, pass through the embeded atom.In addition, the tetrahedral interstitial compounds may be synthesized successfully, because elements Sm, Eu etc.are in the lower valent states which make the contraction of d and f orbitals lessen and the bonding capability increase.And rich-electron f orbitals in Yb-system have become the major valence orbitals.
    The Theoretical Study of the Effects of Dopants on the Properties of Polyacetylene
    WANG Rong-shun, MENG Ling-peng, ZHAO Cheng-da
    1992, 13(6):  787-790. 
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    A finite polyene C29H31 is employed to simulate the conjugated polymer molecule of polyacetylene.The effects of various dopants on soliton in polyacetylene were studied by using CNDO/2 level semiempirical quantum chemical method.The width of soliton is contracted when dopant is present.The effects of p-type dopants are greater than those of n-type ones.The charge density wave in polyacetylene chain is affected by the dopants and is closed to near the carbon atom of the soliton.The action between HOMO of dopant atom and spin orbital of soliton in the polyacetylene strengthened in proper order from Li to K, when the alkali metal is present, and the experiment result of ESR was explained.
    Studies on Absorption Spectra and Surface Enhanced Raman Spectra of Silver Organosols
    GU Ren-ao, HE Zhang-fei
    1992, 13(6):  791-794. 
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    The effects of 2-aminobenzoimidazole(BIMNH2), NaOEt, LiCl on the absorption spectra and surface enhanced Raman scattering (SERS) spectra are studied.The experimental results indicate that a samll amount of adsorbed molecules, NaOEt, LiCl can influence the aggregation of silver organosols, and the absorption spectra and SERSspectra.Additionally, Cl- forms surface complex compound with Ag, BIMNH2, as a result, the SERSspectra are enhanced.The effect of solvent on SERS spectra are initially studied.
    The Catalytic Esterification of the Rare-Earth Oxidate UFPs
    GAO Zhi-ming, KANG Shi-zhao, WU Tong-hao, PENG Shao-yi
    1992, 13(6):  795-797. 
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    Five kinds of rare-earth oxidate ultrafine powders were prepared, and the activity of their catalytic esterification was investigated.It is found that the activity of the UFPs is higher than that of the conventional ones.When Y2O3-UFP is used as the catalyst for esterification, the value of acidity of the product almost reached 0.1.It has broad prospects for application.
    An Expression of Quantum Electrochemistry for Exchange Current
    ZHANG Lin-shao
    1992, 13(6):  798-800. 
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    A theoretically derived expression of the exchange current is presented by using the general expression of thermal activation theory.The calculated values of the exchange current of Fe and Ni electrodeposition are in agreement with the experimental ones.
    Quantum Topological Study on the Structure of Chemical Bonds in Alkylidenecarbene and Lithio-Fluoro-Carbenoid
    MENG Ling-peng, CAI Xin-hua, ZHENG Shi-jun
    1992, 13(6):  801-803. 
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    The structure and properties of singlet and triplet alkylidenecarbene, H2C＝C , were studied with topological analysis of electronic charge density at ab initio(3-21G) level.The orientations of electrophilic and nucleophilic reactions can be explained on this basis.As for lithio-fluo-ro-carbenoid, H2C＝CLiF, four equilibrium geometries were studied.The results show that in carbenoid species, Li and Hatoms did not form a chemical bond, there is no four-membered-ring in the molecule, and electrostatic interaction is dominant in Li-C bond.The mechanism for addition reaction of carbenoid would be predicted.
    Theoretical Analysis of the Fluorescence Spectra of LaOX : Dy3+ Phosphors
    YANG Pin, LI Si-dian, WANG Yue-kui
    1992, 13(6):  804-808. 
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    The phosphors LaOX:Dy3+(X=Cl, Br) were synthesized by a modified ammonium halide method.Their fluorescence spectra were measured at room and liquid-nitrogen temperatures, and were analysed based on the theoretical energy levels of Dy3+ calculated with the Double Sphere Coordination Point Charge Field (DSCPCF) model.The agreement between the calculated and the observed transition wavelengths is generally good.
    Studies on the Device of Molecules with Nonlinear Optical Second-Order Susceptibilities
    FENG Ji-kang, GAO Xu-ling, SUN Jia-zhong
    1992, 13(6):  809-812. 
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    On the basis of INDO/CImethods and according to the sum-over-state expression, we design the program for calculating the nonlinear second-order optical susceptibilities βijk and examine the effect of molecular backbones, substituents of electron acceptor, and substituents of electron donor on the NLO susceptibilities βx.We also design a molecule with the biggest second-order NLO susceptibility βx.All calculated results are in good agreement with experimental results.
    Studies on Steady-State Kinetics of Cytochrome c Oxidase
    ZHAO Jian-gang, YANG Tong-shu, ZHANG Xue-zhong, CHENG Yu-hua
    1992, 13(6):  813-815. 
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    The steady-state kinetics of CCOwas studied by spectrophotometry.It is indicated that there are both higher and lower affinity phases when CCOreacts with its substrate ferrocy-tochrome c.The catalytic reaction is regulated by the concentration of the substrate and has a character of single substrate multiphasic kinetics.
    Studies on Synthesis and Surface Activities of Glutamic Acid Dialkyl Ester
    ZHANG He-zhe, BAI Guang-yue, WANG Yu-jie, YAN Zhong
    1992, 13(6):  816-818. 
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    A series of glutamic acid dialkyl esters (abbreviated as 2R-GE) as new surfactants were synthesized.The surfactants have two long alkyl chains, and both of them are C8, C10, C12, C14, C16, C18, and C18△9,10 respectively.The structures of the products were identified by IR and NMR.Through measurement of the interfacial tension and surface pressure, the surface activities were studied.The results show that they are a series of surfactants with much better activity.
    Studies on Redox Properties of the Catalyst Cu-Fe-Ce-O/γ-Al2O3
    LU Guan-zhong, WANG Ren
    1992, 13(6):  819-823. 
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    TPR, XPSand FTIRwere used to study the redox properties of the catalyst Cu-Fe-Ce-O(Ⅰ) supported on alumina.The results show that copper in (Ⅰ) has much stronger reduction and reoxidization properties, the presence of which facilitates the reduction of iron.Cerium as a promoter can enhance the redox properties of Cu-Fe-O(Ⅱ) supported on alumina.The studies on the samples pretreated by COor/and NOindicate that the adsorption of NO on iron is stronger than that on copper and the adsorption of COon copper is stronger than that on iron.The presence of cerium can enhance the adsorption of COin the reaction of CO+NO and has influence on the adsorption of NOin nitrates on (Ⅱ).
    Effects of Temperature on the Viscosity of Nonionic Micellar Solution in the Presence of Salts
    HUANG Zhi-zhen, CHEN Zong-qi, XUE Mei-ling, SHI Cai-yun
    1992, 13(6):  824-827. 
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    The effects of temperature on the viscosity of nonionic surfactant, OP, in the presence of the added salts are presented.It is found that the plots of logarithm of the relative viscosity vs 1/T are linear.The activation free energies (△G*) of the viscous flow were obtained from the slopes of these plots.The activation enthalpies (△H*) and entropies (△S*) for the viscous fluid were calculated out and the entropic contribution was found to be negligible.△G* and △H* were highly dependent on the ethylene oxide number and the nature of positive ions.The △G* is interpreted in terms of the energy required to create a hole or an activated transition micellar structure capable of being transformed into smaller spherical mecelles.
    Studies on HPA Catalyzing the Reactions for Sulfonating Aromatic Hydrocarbons to Aryl Sul phone by Means of Variable Temperature 1H NMR
    WU Tong-hao, HUA Shi-ying, LI Yong-guo
    1992, 13(6):  828-831. 
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    In this article, the interaction between HPA catalyst and arenesulfonic acid is studied by means of variable-temperature 1H NMR.The mechanism of HPA catalyzing the reactions for sulfonating aromatic compounds to aryl sulphone is proposed.The proton from HPA plays a main role in these reactions and HPAN has influence over the reaction rate and selectivity.
    Studies on Thermokinetics of the Reaction Between Methylamine and X-Butyrolactone
    DUAN Zhi-hua, WANG Rui-Lin, ZENG Xian-cheng, DENG Yu
    1992, 13(6):  832-833. 
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    In this paper the reaction between methylamine and r-butyrolactone was investigated by using the method of dimensionless parameter for first order reactions.The molar enthalpies and the rate constants of the reaction were calculated out at 15 and 25℃, which have not been reported in literatures.
    Nonadiabatic Interactions in [2+4] Photocycloadditions
    LI Xiang-yuan, HE Fu-cheng
    1992, 13(6):  834-836. 
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    The S1→S0 nonadiabatic coupling terms are calculated for different reaction modes of concerted [2+4] photocycloadditions in the Huckel-Hubbard approximation.The nonadiabatic transition probabilities are estimated by means of the Landau-Zener model as well.The calculated nonadiabatic coupling terms and transition probabilities show clearly the differences between the nonadiabatic interactions of the two reaction modes s+a (or a+s) and s+s.With these calculated results the stereospecifities in concerted [2+4] photocycloadditions are correctly predicted.
    Theoretical Study on the Regioselectivity of Intramolecular N-4-pentenyl Nitrone Cycloaddition
    MA Si-yu, FU Xiao-yuan
    1992, 13(6):  837-839. 
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    The reaction mechanism of the intramolecular cycloaddition of N-4-pentenyl nitrone was investigated theoretically by using AM1 MO method and transition state theory.There are two parallel reactions leading to two different regioisomers.The geometries of the reactants, TSand products were optimized.The ratio of the rate constant of the two reactions is 1.2 (at 383.75 K) and is in good consistence with experiments.
    Studies on the Interaction Between Amino Acid and Ion Exchange Resin (Ⅱ)——Mechanism of Superequivalent Adsorption of Amino Acid on Ion Exchange Resin at High Concentration
    ZHANG Bao-lin, SHENG Fen-ling, TAO Zu-yi
    1992, 13(6):  840-842. 
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    The adsorption isotherms of glycine, the infrared spectroscopy of glycine adsorbed on the ion exchange resin and the desorption rate of glycine from the ion exchange resin were used to study the mechanism of superequivalent adsorption of amino acid on the ion exchange resin.It can be concluded that the mechanism of the superequivalent adsorption is the formation of the second layer of glycine molecule, and the carboxylic groups of the first layer of glycine on the ion exchange resin act as the exchange sites for the second layer of glycine.
    Studies on the Adsorption Model of CO on Ni(100) Surface
    CHEN Shu-zi, ZHA Kun-wei
    1992, 13(6):  843-844. 
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    The adsorption models of COon the surface of Ni(100) under different conditions were calculated by an improved LEPSmethod.The calculation results show that when COis parallely approaching to the Ni(100) surface with CObond, the adsorption of dissociated atoms Cand Owill occur at the best position of two diagonal by adjacent 5CNat a distance of 1.325 a.u.from the surface and an energy barrier of 2.5 eVmust be overcome.If C-Obond is vertically approaching to the Ni(100) surface, there is a molecular adsorption and the best adsorp-tive position is 5CN.
    Studies on the Thermokinetics of the Oxidation Reaction of Alcohol by NBS
    WANG Rui-lin, QIN Zi-ming, DENG Yu, CHEN Yong
    1992, 13(6):  845-846. 
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    In this paper, the oxidation reaction of iso-propanol and cyclohexanol by NBS was dealt with by using the dimensionless parameter method of thermokinetics.The reaction order was determined and the reaction rate constants obtained are quite consistent with the values in literatures.The rational explanation for the reaction mechanism was given.
    Studies on Behavior of Deuterium and Hydrogen In Palladium
    DONG Qing-hua, QIU Wan-chuan, GAN Fu-xing, CAI Nai-cai
    1992, 13(6):  847-849. 
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    The absorption, reserve, diffusion of deuterium and hydrogen in palladium, and the positron lifetime of palladium during electrolysis are investigated by hydrogen permeation method and positron annihilation spectroscopy.The results show that the electrochemical behavior of deuterium is almost the same as that of hydrogen, but the amount of deuterium reserved in palladium is lightly less than that of hydrogen and the diffusion coefficient of deuterium is slightly greater than that of hydrogen.The positron lifetime in palladium after electrolysis is increased by 10.5%.The behavior similarity of deuterium and hydrogen and the possibility of "cold nuclear fusion" are disscussed.
    Dynamic Adsorption Studies on Surfactants on Solid Silver Surface with a Quartz Crystal Microbalance
    ZHOU Tie-an, XIAO Xiao-hui, NIE Li-hua, YAO Shou-zhuo
    1992, 13(6):  850-852. 
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    The adsorption of ionic surfactants (cetyltrimethyl-ammonium bromide, sodium dodecylsulf onate, sodium dodecylsulfate) on the solid silver surface is studied in situ by using the liquid quartz crystal microbalance.The adsorption isotherms obtained indicate that they obey different adsorption mechanisms.The adsorption layer of the surfactants on Ag is not firmly fixed and can be physically desorbed.
    Soap-Free Emulsion Copolymerization of MMA-BA (Ⅰ)
    JI Qing-xu, CHENG Shi-yuan, LI Jian-zong
    1992, 13(6):  853-856. 
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    Soap-free copolymerization of methyl methacrylate(MMA) and butyl acrylate(BA) in the presence of surface active comonomer, sodium undecylenate (at concentration below its CMC) was carried out.The particle size(Dw), number(Np), morphology and surface properties were charaterized with particle size analysizer, TEM and ion-exchange-conductimetric titration respectively.The results indicated that Dw and Np could be controlled by adjusting the temperature , the concentration of SUAand KPS, ionic strength, and the ratio of MMA to BA, while the particle surface properties were decided by SUA content, ionic strength and the ratio of MMA to BA.
    Structure and Properties of Multicomponent Metal-Containing Transparent Resin
    JIA Chun-xiang, YANG Bai, LIN De-hou, LI Ying-jun, SHEN Jia-cong
    1992, 13(6):  857-860. 
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    In this paper, transparent resin——copolymer of styrene, bisvinyl poly (ether-sul-fone)s macromonomer(PES-3-MA), Pb(MA)2, Ba (CA)2 was synthesized, and the relation between structure and properties of the multicomponent transparent resin was studied.The experimental results indicate that with the increases of PES-3-MAor Pb(MA)2 ratio, the density of the resin will increase, the linear expansion coefficient a will decrease to 50～70×10-6℃-1, Tg arise to 140℃.It was obtained that D204p(PES-3-MA)=1.33, D204p[Pb(MA)2]=2.10.This is consistent with the calculated value.Studies by FTIRshow that if one wants pendant vinyl bond to react completely, high temperature heat treatment is needed.
    Rheological Properties of CPVC/SMA Blends
    SHI Tie-jun, WEI Chun-ming, ZHANG Zheng-bai
    1992, 13(6):  861-863. 
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    Rheological properties of chlorinated poly (vinyl chloride)/styrene maleic anhydride copolymer (CPVC/SMA) blends were studied.It is shown that the relationship between viscosity and shear rate for each blend may be expressed with a second order equation, and the relationship between viscosity and shear stress with Sper.cer-Dillon experiential equation.The viscosity of system at 180℃ or 190℃ showc a minimum with increasing shear rate at SMA content 20%.and the minimum at 205 ℃ disappears at SMA content 20%.
    Crystal Structure of the Quenched and Annealed Samples of Nylon 1010
    ZHU Cheng-shen, MO Zhi-shen, MU Zhong-cheng
    1992, 13(6):  864-866. 
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    The present paper covers the relationships between the crystallinity Xc, crystalline size L100, and relative diffraction strength of plane parallel to hydrogen-bonds'sheets R, with the quenched conditions and annealed temperature Ta for the quenched and annealed samples of nylon 1010 studied by WAXD.For the samples that were quenched at room temperature and then annealed (RT), if Ta <196℃ , Xc and L100 are increased with the raising of Ta, Rdecreased ; if Ta >196℃, the relations are turned back.For quenched in liquid N2 and then annealed samples (LN) , Xc and Rare increased with Ta raising, but L100 has not any regularity.At the same time Ta, Xc and L100 of RT samples are larger than those of LN samples, but Rand the increment of crystallinity of LN in the annealed process are larger than those of RT.
    The Isothermal Crystallization Kinetics of PET Under Solid State Poly condensation
    LI Li-qing, ZHOU Wei-hua, TANG Xin-yi
    1992, 13(6):  867-869. 
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    The present paper covers the isothermal crystallization kinetics of PET with different mol.wt.that were got by solid state polycondensation.The experimental result shows that in the case of solid state polycondensation no matter whether the crystallization process begins from the melt state or from the glass state, the isothermal crystallization process in later stage can be described well by modified Avrami equation.t0 (the collision time of spherulites), t1/2 as well as the isothermal crystallization rate are discussed.Furthermore, the influences of mol.wt.of PETand temperature on the crystallization rate was also studied.The results also show that the crystallization rules of PETgot from solid state polycondensation are basically the same as that of samples got from melt polycondensation.
    Application of Derivative UV Spectrometry to the Composition Determination of Polystyrene-based Copolymers
    QIU Yong-xing, FENG Lin-xian, YU Xiao-jie, YANG Shi-lin
    1992, 13(6):  870-872. 
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    Because of the background absorbance of stearyl poly(ethylene oxide), big errors arise when normal UVspectrometry is used to determine the polystyrene content of polystyrene-g-stearyl poly (ethylene oxide) (PS-g-SPEO).In order to eliminate the interference of SPEO, we developed the first derivative UV spectrometry for the quantitative composition determination of PS-g-SPEO.It was discovered that the undesirable background absorbance mentioned above could be completely eliminated and the compositions of PS-g-SPEO copolymers determined from the first derivative spectrometry coincide quite well with the data derived from elementary analysis.The results indicate that the nrst derivative UVspectrometry is a feasible and accurate method for the composition determination of polystyrene-based copolymers.
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