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Table of Content

    24 February 1997, Volume 18 Issue 2
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    Articles
    Synthesis and Characterization of Layered Phosphotoantimonic Acid-Intercalated Cobalt Porphyrin and Its Catalytic Behaviour to Hydroperoxide Decomposition
    HU Xi-Ming, CHEN Bi-Yun, Pl Zong-Xin, MEI Zhi-Qian, GU Guo-Bang, HUANG Zhong-Tao
    1997, 18(2):  167-171. 
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    Astepwise synthesis method was used to intercalate cobalt tetraphenylporphyrin into the layered phosphotoantimonic acid host material.The characterization of the purified sample layered phosphotoantimonic acid-intercalated cobalt porphyrin was made by the method of IR, powder XRD, UV-Vis and EPR.Layered phosphotoantimonic acid-intercalated cobalt porphyrin exhibits a fairly catalytic behaviour to hydroperoxide decotnposition, which indicates the intercalation of the porphyrin could result in the prevention of the formaaion of u-dimers and the increased catalytic capabilities.
    Studies on Synthesis and Properties of Layered Zirconium Phosphate
    ZHANG Hua, XU Jin-Suo, TANG Yi, GAO Zi
    1997, 18(2):  172-176. 
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    The crystalline a-Zr(HPO4)2·H2O(a-ZrP) was prepared by three different methods - reflux, hydrothermal crystallization and HFprecipitation.The a-ZrPsample obtained by the HFprecipitation is the largest in size and the highest in sheet orderliness, while the sample prepared by the reflux method is the smallest in size and the lowest in sheet order1iness.The highest unit-layer crystallinity of a-ZrPcrystal was obtained by hydrothermal method.With the crystal size and the sheet orderliness of the crystal increasing, the dehydration temperature rises, and more alkylamine or amino-alcohol is needed to intercalate into a-ZrPfor its colloidization.The samples from HFprecipitation and reflux methods are easier to hydrolyze than the sample from hydrothermal method, but the hydrolysis percentage of all samples from three different methods are lower than 20%, even if the concentration of amine reaches the equivalent point.
    Studies on Synergistic Extraction of Rare Earths(Ⅲ) with HBTMPTP and Primary Amine N1923
    KONG Wei, WANG Chun, LI De-Qian, ZHANG Xiu-Ying, WANG Chao-Min
    1997, 18(2):  177-181. 
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    The synergistic extraction of rare earths (Ⅲ) with binary systems containing HBTMPTPand primary amine N1923 from sulfuric acid medium was observed. The synergistic extraction factor(R) decreased with increasing atomic number of lanthanides.Through the methods of slope analysis, constant mole and saturation titration, the synergistic extraction stoichiometry was obtained.The thermodynamic function was calculated.The IRspectra of the saturated synergistic extraction completely confirmed the mechanism.
    Phase Diagram of EuI2-LiI and EuI2-NaI Binary System
    ZHAO Zhi-Gang, WANG Shi-Hua, JIANG Sheng-Bang
    1997, 18(2):  182-185. 
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    The EuI2-LiIand EuI2-NaIsystems were studied by differential thermal analysis (DTA) and X-ray powder diffraction.The phase diagram of EuI2-LiIis eutectic one.The results show that the eutectic point is at 385 ℃with molar composition 68.5% LiI.The phase diagram of EuI2(Nal is an eutectic point too, the eutectic point exists at 409 ℃with molar composition 32% NaI- In both two systems the crystal transitiori of EuI2 at 354 ℃ has been found.
    Effect of Crystallization Temperature on Structural Transformations of Mesoporous Molecular Sieve M41S Materials
    CHEN Xiao-Yin, DING Guo-Zhong, CHEN Hai-Ying, LI QuanAnZhi
    1997, 18(2):  186-189. 
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    The effect of crystallization temperature on the structural transformations of mesoporous molecular sieve M41Smaterials was described for the cetyltrimethylammoniumsilicate system at a low surfactant/silica ratio and a low surfactant concentration.With increasing crystallization temperature to 135 ℃,the texture of originally formed hexagonal MCM-41 is changed.When crystallization temperature increases to 150℃, the thermal stability of M41Smaterials is decreased due to the transformation of mesoporous structure from hexagonal MCM-41 lattice to thermally unstable lamellar phase.Further increasing crystallization temperature to or above 165℃, the microporous ZSM-5 type zeolite instead of mesoporous M41Smaterials is formed in the same synthetic system, resulting from the structural transformation of M41Sto ZSM-5.
    A Study of Phase Equilibrium Diagram of Quaternary System KBr-RE (La,Sm)Br3-HBr-H2O at 25 ℃
    WANG Hui, RAN Xin-Quan, CHEN Pei-Heng
    1997, 18(2):  190-192. 
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    Phase chemical relation of quaternary systems KBr-REBr3-HBr (13%)-H2O (25℃, RE=La, Sm) were determined, and the rule of phase change was also discovered bere when REare light rare earth elements.It is found from the experiment that the quaternary systems in which KBr and REBr3 react in hydrobromic acid belong to a simple eutectic type,so the reaction mechanism for synthesizing compound K2REBr5 type and real action of the first step reaction can be explained with Meyer's method.Furthermore, it can be seen from comparison between the systems in this paper and the system CsBr-REBr-HBr (13%)-H2O (25℃) that CsBr and REBr3 acting in hydrobromic acid with each other can form doublecompound easier than KBr and REBr3.
    Crystal and Molecular Structure of Mn (15-Crown-5) (NCS)2
    WEl Yun-He, DAI Ying, HUANG Bai-Biao
    1997, 18(2):  193-195. 
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    The single crystal of Mn (15-Crown-5) (NCS)2 was obtained by solvent evaporation method, and the structure was solved from X-ray diffraction data by direct and Fourier methods.The crystal belongs to a triclinic system, space group is P1 with unit cell parameters: a=O.7126(2) nm, b=O.8469(1) nm, c=1.6031(4) nm, a=74.55(2)°β=76.29 (2)°, γ=74。 05(2)°, and Z=2, V=0.8825(4) nm3, Dx=1473 kg/m3, p=O.6956 lnm-1,F (000)=406- Mn (Ⅱ) coordinates derectly with five oxygen atoms of the 15-mcrown-5 and two nitrogen atoms of SCN- to form a seven coordinated compound.The five oxygen atoms lie in a plane approximatively- Mn(Ⅱ) is in the centre, and the two SCN- are situated on both sides of the plane.Mn(Ⅱ) adopts sp3d3 hybrid orbitals to form coordinated bonds.
    A New Chemical Clustering Analysis Method Based on Genetic Evolution Algorithm
    CHEN Wen-Can, CUI Hui, ZHANG Lin, LIANG Yi-Zeng
    1997, 18(2):  196-201. 
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    Genetic evolution strategy (GEs) was used in chemical clustering analysis.The clustering objective was formulated as a function of real-valued parameters.Combinatorial optimization usually encountered in clustering analysis, which is commonly time-consuming in computation, can be avoided, and therefore, the amount of computation can be significantly reduced.Global optimum might be achieved with the help of genetic algorithm.Results obtalned from four real chemical data sets substantiate the practicability of the method proposed in the paper.
    Development and Application of Chromatographic Grey Model(Ⅰ)──Establishment of Continuous Grey Model GM (1,N) and Prediction of Chromatographic Retention Behaviour
    SUN Zhao-Lin, ZHANG Su-Ping, ZHANG Xiao-Tong, SONG Li-Juan, ZHOU Shan-Hua, LU Bin, BAI Jian-E
    1997, 18(2):  202-206. 
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    The continuous grey model GM(1,N) has been derived from the grey theory and the principle of the least-square.The model has been successfully applied to predict the solute retention behaviour in high performance liquid-phase chromatography.The grey model GM (1,N) had been used not only to describe the relationships between the capacity factor of solute and mobile phase composition or solute's carbon number, but also firstly to investigate the relationships between the retention time of solute and column temperature or carbon number of n-alkanes, n-alkylbenzenes and p-bydroxybenzoates.Simultaneously, we established the corresponding mathematical model.The predicted results are satisfactory.
    A New Technique of Pre-polymerization for Preparation of Polyacry-amide Gel Filled Capillaries for Capillary Gel Electrophoresis
    HU Yong-Gang, DENG Yan-Zhuo
    1997, 18(2):  207-211. 
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    Anovel method "pre-polymerization" for production of cross-linked polyacrylamide gel filled-capillaries was studied in detail.Many factors of this method which contribute to the ratio of success for producing the gel-filled capillaries were discussed.i.e.,characters and pureness of Acr and Bis, use level of TeMEDand AP, effect of pHvalue and other characters of buffer, time of polymerization, diameter and length of capillaries, and conditions of preservation and so on.This method was demonstrated to be applicable to the production of gel-filled capillaries with wide varieties of gel composition, capillary diameters and capillary lengh.Over 9O% ratio of success for producing the gel-filled capillaries was obtained with this method.Retroreflective laser beams interference phase-shift detection was used for on-column detection of proteins in cross-linked polyacrylamide gel capillary electrophoresis (CPAGCE) firstly.For ovalbumin, 4.2 ×10-7 mol/L(S/N=2) of detection limit was measured and 1.66 ×105 theoreticaｌplates was observed on the home-made CEsystem.It should prove attractive for a number of applications in separation of biological macromolecule samples with the gel-filled capillaries produced by the method of pre-polymerizatlon.
    A New PLS Method Suitable to Deal with the Discriminant Analysis Problems with Two Class Samples
    ZHU Er-Yi, LIN Yong-Jing, ZHUANG Zhi-Xia, YING Hai
    1997, 18(2):  212-215. 
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    Anew PLSmethod that is very suitable dealing with the discriminant analysis problems with two class samples has been developed.In this method the dependent function y has been transformed by use of the Sigmoid function, that is similar to the neural network algorithm.Therefore a new optimization criteria can be used to extract the latent variables t1, t2,...., in PLSmethod.The good classification graphics constructed by the latent variables, and the ideal direction vectors of discrimination can all be obtained.
    DNA Ploidy Analysis of Breast Tumor Cell by the System of Hadamard Transform Microscopic Image Analysis
    TANG Hong-Wu, MEl Er-Wen, CHEN Guan-Quan, ZENG Yun-E, MAO Yong-Rong, HE Ping, SHI Z0ng-Jie
    1997, 18(2):  216-219. 
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    Normal human lymphocyte was used as standard diploid cell, acridine orange was used as fluorescence probe for DNAin cell, and DNAploidy of six cases of human breast tumor was analyzed by the system of Hadamard transform microscopic image analysis.Some parameters were employed to evaluate tumor malignancy, the results are concordant with pathological diagnosis, this indicates that the above instrument may be applied in diagnostic and prognostic study on human breast cancer.The results also show that significant positive correlation exists between tumor cell nuclear DNAploidy and its area (pixels).
    Effect of F- Axial Coordination on the Electrochemistry of (TPP)Co
    YAN Chuan-Wei, LIN Xiang-Qin
    1997, 18(2):  220-222. 
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    The axial coordination effect of F- on the redox behavior of (TPP)Co was investigated by F- titration with cyclic voltammetry detection and spectroeletrochemistry in dichloroethane.It was verified that mono(F-) axial adduct (TPP)Co(N) (F-) could be reduced at O.1 V(SCE), and bis(F-) axial adduct (TPP)Co(Ⅲ) (F-)2 formed with added Fmolar ratio>1 could be reduced at the potential <-0.6 V(SCE).The equilibrium between (TPP)Co(Ⅲ) (F-) and (TPP)Co (Ⅲ) (F-)2 was demonstrated.
    Integrating Multivariate Statistical Analysis with Neural Networks for Pattern Classification of Complex Chemical Information
    CHEN De-Zhao, CHEN Ya-Qiu, LIN Gao-Fei, HU Shang-Xu
    1997, 18(2):  223-225. 
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    Anew method by integrating the multivariate statistical analysis with neural network used for complex pattern classification was proposed in this paper.First, a particularly developed statistical method called correlational components analysis was employed to extract pattern characteristics from the original sample pattern space.These pattern characteristics were then used as inputs to a multi-layered feedforward neural networks for further pattern classification, The proposed approach transforms the complex patterns into lower dimensional and mutually decoupled ones, it also takes the advantages of the self-learning capability of the neural networks.Finally, a practical example of natural spearmint oil was used to verify the effectiveness of the new method.The results showed that the proposed integrated approach gives better results than other conventional methods.
    Investigations on Carbon Fiber pH Ultramicrosensor Modified by Polyaniline Film and Its Applications to the in vivo Detection on Brassica Stigmata
    WAN Qi-Jin, ZHANG Xue-Ji, ZHANG Chun-Guang, ZHOU Xing-Yao
    1997, 18(2):  226-228. 
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    ApHultramicrosensor based on polyaniline film modified carbon fiber microcylinderelectrode in proposed.The film is introduced onto carbon fiber surface by electropolymerization of aniline, The sensor exhibits a linear response over the range 2-12.5 pH, with a near Nerstain response slope (60 mV/pH) at room remperature.The correlation coefficientis 0.9999.The average response time at the sensor is about 2 min.The selectivity coefficient obtained for lgKHPOt+.Mn+ are - l1.9, - 12.1, - l2.Oand -11.6 for K+, Na+, Li+ and Ca2+, respectively.The sensor was employed for measuring the pHof tap water, lake water and fresh urine.The results obtained from the sensor are in good agreement with those from the glass pHelectrode.The sensor has been used for in vivo detection of pHon surface microenvironment of Brassica stigmata and pollen grains with satisfactory results.
    Preliminary Research on Mechanism of the Isomerization/Chlorination of O, O-Dialkylthiophosphate (-onate)with Phosphorus Oxychloride
    TANG Chu-Chi, MA Fu-Peng, HE Zheng-Jie
    1997, 18(2):  229-233. 
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    In the previous papers, we reported that O,O-dialkylthiophosphate(-onate) 1 reacted with phosphorus oxychloride to give S-alkyl thiophosphoro (-on-)chloridate 2 and Oalkyl phosphorodichloridate 3.Obviously both of isomerization and chlorination occurred in this reaction.The recent experimental results show that phosphorus oxychloride doesn' t react with O-alkyl thiophosphoro(-no)chlorldate 5 which is a desired chlorination product of 1,while it can smoothly react with O,S-dialkythiophosphate(-onate) 6 which is a desired isomerization product of 1 to give 2- Based on this fact we suggest that the isomerization may occur ahead of the chlorination in the isomerization/chlorination of 1.In the light of the above results and trigonal bipyramid (TBP) intermediate concept, the mechanism 0f the isomerization /chlorination of 1 is discussed.
    Synthesis of Tweezer Molecule and Complexation Effect for Organic Anion
    LU Guo-Yuan, LI Qian, SONG Cheng, HU Hong-Wen, Javier de Mendoza
    1997, 18(2):  234-237. 
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    This paper reports the synthesis and NMRstudies of a novel tweezer molecule (2S, 8S)-2- (2-naphthoyl oxymethyl)-8- (2-naphthoyl aminomethyl)-1, 5, 9-triazabicyclo [4.4.O] dec-5-ene chloride.The complexation effect of the tweezer molecule and pnitrobenzoate salts by means of 1HNMRshows that they are self-associated by hydrogen bonding,electrostatic interaction and arene-arene sandwich stacking interaction.
    Studies on Mechanism of Reaction of Dichlorocarbene with Tetraphenylcyclopentadienone
    GU Wen-Xiang, WANG Hong-Xing, PAN Yin-Ming, HUAN Zhen-Wei, CHENG Jin-Pei
    1997, 18(2):  238-241. 
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    The reaction of dichlorocarbene with tetraphenylcyclone (1) resulted in carbon monoxide and gem-dichloro compound (3) together with dichlorooxirane (4) and adduct (5).The aromatic structure of carbonyl Ylide and its twist geometry led to deoxygenation to be the main reaction pathway.
    Hammett Relationship in Cyclohexane Hydroxylation Catalyzed by Metalloporphyrins
    GUO Can-Cheng, LI Zhi-Peng, LIANG Ben-Xi
    1997, 18(2):  242-246. 
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    Forty mono-iron and manganese porphyrins, u-oxo bis-iron and manganese porphyrins with different substituents Ron the porphyrin peripheral ring were synthesized.The cyclohexane hydroxylation catalyzed by these metalloporphyrins under mild conditions and the self-oxidation of these metalloporphyrins with PhIOwere studied.The linear free energy relationship was first found for above reaction systems.Some new results and rules were obtained by carrying out correlation analysis for these two reactions.According to these results and rules, a possible mechanism for the hydrocarbon hydroxylation catalyzed by metalloporphyrins was proposed.
    A Study of the Interaction of Saporin-S6 and Lipid Bilayers
    LIU Guo-Hong, HAO Qiang, ZHANG Yan, YAN Li, LI Qing-Shan
    1997, 18(2):  247-249. 
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    The physical state changes of phospholipid bilayers, when they interact with Saporin-S6 (SO-6), were studied by using external fluorescent probes.The protein causes the release of veslcle contents and the lipid bilayers were stirred.SO-6 can decrease the fluidity of phospholipid bilayers.According to these results, a primary mechanism of the interaction of Saporin-S6 and model membranes was provided.
    Theoretical Study on Secondary Bonding in Organo-metallic Compounds(Ⅲ)──The Feature of Structures and Secondary Bonding in Metallic Clusters Ions [M3 (CO)9CCO]2- (M=Fe, Ru, Os)
    LAI Cheng-Ming, TANG Jun, YUAN Man-Xue, NIU Shu-Qiang
    1997, 18(2):  250-253. 
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    In this paper we discussed the features of structure of the metallic cluster anions [M3(CO)9CCO]2－ and adoption of direction of the ligand (COO) to the metal atom and the secondary bonds by means of ICON(EHMO).
    Synthesis and Herbicidal Activity of 1-(p-Toluenesulfonyl)-2-phenoxy-3-alkyl-4-pheny1-1, 4-diazaphospholidin-5-one-2-oxides
    CHEN Ru-Yu, HE Liang-Nian, YANG Xiu-Feng
    1997, 18(2):  254-256. 
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    Aseries of 1-(p-toluenesulfonyl)-2-phenoxy-3-alkyl-4-phenyl-1,4-diazaphospholidin-5-one-2-oxides(2) have been synthesized by the Mannich-type reaction of 1-phenyl-3(p-toluenesulfonyl) urea (1), aliphatic aldehydes and triphenyl phosphite in acetic acid, and their structures were determined by elementary analysis, NMRand MS.The mechanism of the acid-catalyzed reaction was discussed.The results of preliminary vioassay show that compounds (2) possess herbicidal activity against rape.
    A Novel Synthesis of α,α-Dicarbonyl andα-Oxo-α-alkoxide Cyclic O,S-Ethylene Acetales
    ZHANG Shu-Jia, LIU Qun, XIE Zhong-Wei, QIU Xue-Fei, Dilifeiger, ZHANG Qian, LIU Jing-Fu
    1997, 18(2):  257-259. 
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    Anew method for the synthesis of the tit1e compounds 6 is described in this paper.Compounds 6 were obtained by an one-pot reaction process from β-dione and its analogues, 2-bromoethanol and carbon disulfide with potassium carbonate as the base.The possible mechanism is discussed.In this mechanism, a monoanion intermediate 3 is proposed, it reacts with 2-bromoethanol by a sequential nucleophilic and electrophilic reaction process to build the key intermediate 5.6 is formed by the elimination of hydrosulfide from 5.
    A Study on Aggregates of Pyrylium Salt in Non-polar Solvent at Room Temperature
    CHEN Yi, WU Shi-Kang
    1997, 18(2):  260-263. 
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    The photophysical properties of pyrylium salt in different solvents at room temperature were studied.It was found that the aggregates can be formed both in ground state and in excited state in toluene or benzene.This result has been proved by the concentration effect, temperature effect and fluorescence decay.
    Effect of ZrO2 on CuO/γ-Al2O3 Catalyst in Carbon Monoxide Oxidation
    ZHOU Ren-Xian, JIANG Xiao-Yuan, DING Yun-Jie, ZHENG Xiao-Ming
    1997, 18(2):  264-267. 
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    The effect of ZrO2 modification of γ-Al2O3 and CuOcontents on the property of COoxidation and the reduction behavior of CuO/γ-Al2O3 catalysts were investigated by TPR, TGand flowing reaction methods.The results indicate that ZrO2 modification of γ-Al2O3 support could increase the activity of COoxidation of CuO-supported catalysts at low copper loading(CuO<15 %) - The presence of ZrO2 increased the BETsurface area of the catalysts and the amount of reducible CuO.
    The Effect of Co-adsorption on Photovoltaic Properties of Porphyrin, Phthalocyanine/TiO2 Electrode
    MAO Hai-Fang, TIAN Hong-Jian, ZHOU Qing-Fu, XU Hui-Jun, SHEN Yao-Chun, LU Zu-Hong
    1997, 18(2):  268-272. 
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    ZnTSPP/TiO2, GaTSPc/TiO2 and co-adsorbed ZnTSPP, GaTSPc/TiO2, electrodes have been prepared- The spectroscopic and photovoltaic properties of these electrodes have been studied.The results indicate that the electrode co-adsorbed with porphyrin and phthalocyanlne can not only expend the spectra of photo-current action, but also enhance the efficiency of the incidentanphot0n-current-convers (IPCE), especially enhance the efficiency of IPCEof GaTSPc.This is because the aggregates of GaTSPc have no the sensitization effect, and the aggregates of GaTSPc decrease by co-adsorption of porphyrin and phthalocyanine, so the sensitization effect ability of phthalocyanine is increased signification.
    A Theoretical Study of Nonlinear Second-order Optical Properties of 5, 12-Dithia-7, 14-diaza-5, 7, 12, 14-tetrahydropentacene and Related Compounds
    FENG Ji-Kang, GAO Xiao-Shun, XIAO Chang-Yong, SUN Chia-Chung
    1997, 18(2):  273-276. 
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    On the basis of ZINDOmethods, according to the Sum-Over-States(SOS) formula, the program for the calculation of nonlinear second-order optical susceptibilities βijk, βu have been devised.The structures, spectra and nonlinear second-order optical properties of 5, 12-dithia-7, 14-diaza-5, 7, 12, 14-tetrahydro-pentacene derivatives substituted on lateral rings by different substituents and related compounds have been studied.The conclusion is that both donor and acceptor substituted on lateral rings facilitate the nonlinear second-order optical susceptibilities.Coplanar molecules having stronger conjugation effects facilitate the nonlinear second-order optical susceptibilities too.
    Vapour Phase Condensation of Acetaldehyde over Silica Supported Solid Base Catalysts
    JI Wei-Jie, CHEN Yi
    1997, 18(2):  277-280. 
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    Silica supported low loading alkali metal containing catalysts (Li, Na, K, Cs/SiO2) can effectively catalyze the vapor phase condensation of acetaldehyde with dehydration to produce crotonaldehyde with good selectivity (ca.9O%) and stability and moderate conversion.The optimized reaction temperature was in the range of 623-648 K. The approximative order of the reactivity of these solid base catalysts is K/SiO2> Na/SiO2> Cs/SiO2>Li/SiO2. The silicate and carbonate are probably the active phases for the reaction.Increasing the matel loading altered the context and structure of the catalysts, enhanced the coke formation and in turn the production of crotyl alcohol.Asimilar trend was observed when a more basic alkali metal was used or a larger W/Fratio was adopted.
    Studies on Conformational Order of Q-CdS Complex LB Film
    WANG Li-Jun, LI Lin-Song, YU Zhan-Jun, PENG Xiao-Gang, LI Tie-Jin
    1997, 18(2):  281-284. 
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    Under the conditions of the higher surface pressure and deposition speed, ordered organic/CdSnanoparticles complex film was prepared by the reaction of cadmium stearate and H2S."All trans" conformation of -CH2- can be kept well after reaction which is thought to form nanoorder organic-inorganic superlattice material.Bragg (001) diffraction peaks can be observed by means of X-ray diffraction related to 5.02 nm of the long period.The order property of LBcomplex film was shown according to the result of infrared spectrum.The band gap (Eg) of CdSnanoparticle is 3.46 eVwhich increases 1- 04 eVcomparable to that of the bulk material(2.42 eV) from the result of UV-Vis spectrurn.
    A Study of Cu-Mn/SiO2 Catalysts for Methanol Synthesis
    LI Ji-Tao, GAO Li-Zhen, ZHANG Wei-De, LIN Jian-Yi, CHEN Hua-Yi, TAN Kuang-Lee
    1997, 18(2):  285-288. 
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    Cu-Mn/SiO2, impregnation catalysts were studied with respect to their catalytic activity in the synthesis of methanol.Moreover, the means of XPS, Auger, TPRand decomposition of N2Owere also used to characterize the catalysts.The experimental results show that Cu (O) mostly existed on the working surface of the catalysts.The catalytic reaction was promoted by Cu with part of positive charges which was formed by means of long path exchange function between Cu...O-Mn.Therefore, this was favourable for adsorbing and activating CO and H2 on the surface of catalysts and for promoting methanol synthesis.
    A Study of the Surface Dynamics of the PET Films Modified with CF4/CH4 Plasmas(Ⅱ)──The Wilhelmy Plate Method
    ZHANG Liang, XIANG Wei, CHEN Xiao-Dong, WANG Jian-Qi
    1997, 18(2):  289-292. 
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    篢he dynamic behavior of PETsurface modified with CF4/CH4 plasma was investigated by the dynamic contact angle method (Wilhelmy Plate Method) through water immersion.Some of experimental data were given and explained in terms of turning-over models,indicative of the motion of the containing-fluorine surface groups.
    Laser Generation and Mass Spectrometry of AunPm±
    LIU Zhao-Yang, HUANG Rong-Bin, ZHENG Lan-Sun
    1997, 18(2):  293-296. 
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    AunPm±(m=1-21, n=1-20) and (n=1-15, m=1-13) were generated by laser ablating the mixture of gold and red phosphorus powders, and their mass spectra were recorded by a time-of-flight mass spectrometer.The mass spectra were analyzed and the mass distributions of the binary cluster ions were studied as a function of the cluster size.The relative signal intensities of most observed cluster ions exhibit even/odd alternation.With increase of the cluster size, increment of clustering phosphorus atoms, m, is much less than that of clustering gold atoms, and the distribution of m for the same m of AunPm± tends to be narrower.The results suggest that, at least in the larger cluster ions, the clustering gold atoms are bonded together to form the core of the clusters.
    Quantum Chemical Study on N60
    LI Song, QU Hong, LI Qian-Shu
    1997, 18(2):  297-299. 
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    The structure of cage molecule N60 has been calculated by using ab initio method at 6-31Glevel.The optimized stable geometrical structure of N60 is concave cage with twelve concave-down atoms in the cage.The results of electronic structure calculations can be used for explaining the formation of the concave N60 cage.
    Fabrication and Characterization of a Novel Azobenzene SAM-LB Composite Film
    ZHAO Chun-Xia, YU Hua-Zhong, WANG Yong-Qiang, CAI Sheng-Min, LIU Zhong-Fan
    1997, 18(2):  300-302. 
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    Anovel azobenzene SAM-LBcomposite film was fabricated by depositing LangmuirBlodgett monolayer of 4-octyl-4' - (3-carboxy-trimethylene-oxy)-azobenzene (ABD) onto the cysteamine self-assembled monolayer(AET SAM) modified gold substrate.The film stability was greatly improved and the molecular aggregation was effectively prevented by the strong ionic bonding character on the SAM-LBinterface, which was evidenced by both contact-angle titration, RA-FTIRand AFM.The reversible tran/cis isomerization and the clear-cut electrochemical response of cis-azobenzene were observed in the presence of highly organized molecular assemblies.This enable us to carry out a kinetic study of the cis-azobenzene in highly organized monolayers, by which a "more" reversible and unique pHdependent electron-transfer kinetic behavior of azobenzene was shown within the novel SAM-LBcomposite films.
    The Temperature Effect on Micellar Formation in the Amphiphilic Block Copolymer Solution
    ZHANG Xiao-Hong, HUANG Peng-Cheng, WANG Peng-Fei, WU Shi-Kang
    1997, 18(2):  303-308. 
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    Aseries of poly (ethylene oxide) and poly(propylene oxide) block copolymers with amphiphilic structure have been synthesized in this paper.Both fluorescence probe and differential scanning calorimetric methods (DSC) were used to determine the critical micellar formation temperature(CMT) of these copolymers dissolved in water solution.It was found that the diblock copolymer (PEO-PPO) has almost the same properties as triblock (PEO-PPO-PEO) copolymer for which the CMTvalue decreases with the increasing of the length of hydrophobic segment in the molecule of copolymers.But, for another kind of triblock copolymer (PPO-PEO-PPO), its properties are completely different.It is probably due to the fact that the hydrophobic moieties are located at the terminal part of copolymeric chain which causes the solution to form a crosslinking network structure.In addition, by using of the peak wavelength shift phenomenon in fluorescence spectrum of probe compound which was dissolved in solvents with different polarities, the polarity and the degree of organization of internal nuclei in micelle can be evaluated.
    Association and Complexation of Block Copolymer Ionomers(Ⅲ)──Complexation Between SEBS-based Ionomers and Copolymers Containing Pyridine Units
    LIU Wei-Feng, JIANG Ming
    1997, 18(2):  309-312. 
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    Aseries of block copolyme ionomers(BCI) have been prepared.The solution viscosity and thermal behavior of the blends of BCIand pyridine-containing polymers(MVP and SVP) have been investigated.The results show that MVP and SVPcan form complexes with the PS ionomer blocks in BCI leaeing to substantial increases of both the reduced viscosity in solution and temperture of glass transition in bulk.Ni and Cu ionomers show the largest ability of complexation.
    Crystallization Process and Morphology Structure of Poly(aryl ether ether ketone ketone)Containing Meta-phenyl Links
    CHEN Ye, ZHANG Xue-Yan, YANG De-Cai, WANG Jun-Zuo, WU Zhong-Wen
    1997, 18(2):  313-316. 
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    The crystallization process and morphology of poly (aryl ether ether ketone ketone) containing meta-phenyl links (PEEKmK) have been investigated by transmission electron microscopy and electron diffraction.The results indicate that the thin films of PEEKmKisothermally crystallized from both the glassy state and the melt at the temperature range of 180-250 ℃ consist of two kinds of morphological forms, i.e.large (order of um), flat-on single crystals and narrow, lath-like, edge-on lamellae.The latter consists of the spherulites.Meanwhile, the growing process of the two kinds of morphological forms has been discussed.
    Photoinitiated Crosslink Structures and Mechanisms of Low Density Polyethylene
    QU Bao-Jun, XU Yun-Hua, QU Xin
    1997, 18(2):  317-322. 
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    Crosslink structures, photolytic products of benzophenone(BP) as a photoinitiator and their formation mechanisms in BP-photoinitiated crosslinking of low density polyethylene (LDPE) and its model compounds have been studled by solution state high resolution13C NMRand fluorescence spectroscopy etc..Both H-links and Y--type long branches in the photocrosslinked LDPE (XLPE) have been ohserved and identified for the first time.The concentrations of H- and Y-type crosslinks are estimated to be 5.7～16.9 and 7.6～21.6 structure units per 10000 carbon atoms with the XLPEsamples UV-irracliated for 5～10 seconds in the melt, respectively.The main photolytic product of BPidentified is benzopinacol.There are indications that a small amount of a-alkylbenzhydrols are also possibly formed by the reactions of ketyl radicals with alkyl radicals.
    Reversed Duckweed Polymeric LB Film Containing Azo Chromophores and Its Properties of Reversible Optical Storage
    LI Hong-Bin, ZHANG Li, WANG Zhi-Qiang, ZHANG Xi, SHEN Jia-Cong, YANG Yan-Qiang, FEI Haou-Sheng
    1997, 18(2):  323-325. 
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    Areversed duckweed polymeric LBfilm was fabricated by a new kind of amphiphilic polymer which was composed of hexanedlamine-epichlorohydrin slightly crosslinked hydrophilic network and hydrophobic chains conatining p-nitroazobenzene group.This amphiphilic polymer can form stable liquid-condensed monolayer and be transferred as Z-type polymeric LBfilms.This LBfilm combines the order and mobility and it has a well-estab- lished layer structure and azo chromphore is in an isotropic state in each layer.Optical birefringence and dichroism can be laser induced and erased and this reversible birefringence and dichroism can be cycled many times without appearance of any fatigue and show a very good stability.On the basis of photo-induced optical blrefringence and dichroism, it is greatly anticipated that this polymer thin films bearing azo groups can be used as advanced materialsfor optical information storage.
    The Self-assembled Dendritic Supramolecular Complex Based on Electrostatic Attraction
    BO Zhi-Shan, ZHANG Xi, YANG Mei-Lin, SHEN Jia-Cong
    1997, 18(2):  326-328. 
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    Anew kind of dendritic supramolecular complex with porphyrin as a core-centre was prepared based on electrostatic attraction between tetraphenylporphyrinsulfonate anlon and polyether dendritic cations, which was confirmed by 1H NMR, IRand elementary analysis.
    Carbocationic Reaction Between 2, 4, 4-Trimethy 1-2-chloropentane and 1, 1-Diphenyl Ethylene(Ⅰ)──Main Features of the Reaction
    CAO Xian-Yi, ZHOU Xin-Ru, CHU Guang-Cheng, WU Guan-Ying
    1997, 18(2):  329-331. 
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    The carbocationic reaction between 2, 4, 4-trimethy1-2-chloropentane, which is a model compound of polyisobutylene's end group, and 1, ldsdiphenyl ethylene was investigated by high pressure liquid chromatography, it was found that the reaction presents a strong reverse reaction even if at low temperature.The ceiling temperature is about -18℃.The reaction with tirne and effect of concentration of TiCl4, temperature, polarity of solvent on the reaction show that the main features of this reaction are very close to that of carbocationic polymerization of isobutylene.So the reaction would be ideal model reaction for the carbocationic polymerization.
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