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Table of Content

    24 September 1990, Volume 11 Issue 9
    Articles
    Single Crystal ESR Study of Hctcrotrinuclcar Complex [(NH3)5CoImCu(dicn)ImCo(NH3)5](ClO4)6·4H2O
    Chen Dong, Han Shiying, Sui Yunxia, Tang Wenxia, Dai Anbang
    1990, 11(9):  919-923. 
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    Asingle crystal ESRstudy of heterotrinuclear complex [(NH3)5CoImCu (dien) ImCo (NH3)5] (ClO4)6·4H2O which is diluted with diamagnetic complex [(NH3)5CoImZn (dien)ImCo (NH3)5](ClO4)6·4H2O has been carried out at 100K. Two sets of ESR spectra were observed for the magnetic field orientations in the ZX and ZY planes. The spin-hamiltonian parameters are rigourously calculated by using the least-square-fitting method, specially adapted to non-coincident g and A tensor systems. Two sets of principal values and the directions of g and A tensors, which are caused due to the disorder of dien group, are given. The electron spin densities in the 4s and 3d orbitals of Cu( Ⅱ ) being 0. 018 and 0. 557 imply that the bonding between Cu( Ⅱ ) and ligands is not purely but mainly covalent.
    Studies on the Synthesis and Properties of Manganese Silicoaluminophosphate Molecular Sieve
    Han Shuyun, Yu Guirdng, Zhou Ming, Wei Quan
    1990, 11(9):  924-927. 
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    The pure Manganese Silicoaluminophosphate molecular sieve was synthesized by hydrother-mal crystallization. The structure of MnAPSO-5 has been researched by means of electron paramagnetic resonance spectra, infrared spectra, XPS, electron probe, XRD. The results show that the atoms of manganese and silicon entered into the framework of MnAPSO-5 molecular sieve. Their crystal morphology, surface acidity,ability of adsorption and thermal stability were also investigated.
    A Study on Reaction Kinetics of Superoxide Dismutase and Its Model Compounds with Superoxide Ion by Illumination
    Luo Qinhui, Shen Mengchang, Gao Wei, Peng Qingyun
    1990, 11(9):  928-932. 
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    We studied the reaction kinetics of superoxide dismutase and its model compounds μ-bridge-bis-N,N'-1,3-propylene bis(2,6-diacetylpyridine)iminato copper( Ⅱ )(bridge being SCN-,N3-, I-, Br-,Cl- and OH-)by modified illumination method and the rate constants kQ of the reaction were obtained. kQ measured for superoxide dismutase is in agreement with those measured by pulse radiolysis and xanthine oxidase method. Among the six complexes, Cu2L(SCN)(ClO4) has a maximum value of kQ and Cu2L(N3)(ClO4)3 has a minimum one. The reason for different values of kQ was discussed based on the present results and previous paper.
    Studies on Synthesis and Characterization of Silica-Intercalated Hcctorite and Its Cation Function
    Sun Tie, Jiang Dazhen, Liu Ziyang, Li Ying, Min Enze, He Mingyuan
    1990, 11(9):  933-937. 
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    Silica-intercalated hectorite (Si-CLH) with an 001 spacing of 17. 7Å was prepared by hydrolysis and oxidation of synthetic hectorite containing NH2(CH2)3Si(OC2H5)3 at 700℃. The results of high-temperatuer XRD and DTA show that the thermal stability of Si-CLH is higher than that of the parent hectorite. The spacing of pillared hectorite did not vary with changing cation in the interlayer regions. NH3-TPD and pyridine-adsorption IRindicate the presence of both Lewis and Bronsted acidity on the surface of these samples with weaker acid strength. Cracking activity of cumene of pillared hectorite is greatly higher than that of the parent hectorite. The presence of Mg or La retard the rate of active decay.
    Studies on the Fluorescent Decay Kinetic Properties and Time-Resolved Fluorimetry of Rare Earth Complexes
    Hu Jiming, Chen Guanquan, Zeng Yun'e
    1990, 11(9):  938-941. 
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    The fluorescent decay kinetic properties of rare earth complexes and the effects with surfactants, additive ligands and synergistic ions were studied. The fluorescence lifetime were same for the different fluorescence emission of each complex. According to the fluorescent decay properties, two time-resolved fluorimetries were proposed for determination of rare earth ion having longer fliorescence lifetime and shorter fluorescence lifetime. Results are satisfactory for the determination of trace amounts europium and dysprosium in oxides of rare earth and synthetic water samples.
    A Study on Method for Determination of Apparent Stability Constants of Complexes by Means of Polarographic Adsorptive-Coordinating Wave
    Wang Xiaoping, Zhang Zuxun
    1990, 11(9):  942-946. 
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    The common method for determining the apparent stability constants of complexes with po-larographic adsorptive-coordinating wave is modified, and a more generalized theoretical equation for the determination of the apparent stability constants of complexes is proposed. Approach.to the calculation is made. The good results are obtained as expected.
    Separation and Determination of Trace Amounts of Copper,Zinc,Iron andManganese with meso-Tetra-(4-Sulfophenyl)porphyrin Complexesby High Performance Liquid Chromatography
    Xu Xuejun, Zhang Huashan, Zhang Chuanyou, Cheng Jieke(Jaikai)
    1990, 11(9):  947-951. 
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    In this paper, chelating reactions of meso-tetra-(4-sulfophenyl)porphyrin(TPPS4) used as the derivation agent in front of the column with Cu(Ⅱ),Zn(Ⅱ),Fe(Ⅲ) and Mn(Ⅱ ) have been studied. The chelates were separated on a ODScolumn(5 μm,200℃ 4. 6 mm i. d.) and eluted with acetonitrile-water(40 : 60,V/V,mobile phase) containing 10 mmol/Ltetrabutylammonium bromide (ion pair reagent) and 10 mmol/Lacetic acid-sodium acetate buffer(pH 4.1), and detected at 420 nm. A new method for rapid separation and determination of trace amounts of Cu,Zn,Fe and Mn by reversed-phase ion-pair HPLCis proposed. The detection limits (×10-3 ppm) are 3. 6, 0. 93, 0. 70 and 1, 8 for Mn, Zn, Cu and Fe respectively.This method has been successfully applied to the determination of Cu, Zn, Fe and Mn in the standard sample of peach leaves. The analytical results are in agreement with standard reference values.
    A Study on the Fluorescence Spectra of Benzoxazolyl-Substitutcd Compounds
    Zhou Yimin, Xia Xiaoping, Gao Zhenheng
    1990, 11(9):  952-957. 
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    Absorption spectra, emission spectra and fluorescence yield were measured for thirty-eihgt benzoxazolyl-substituted compounds. From the data radiative and nonradiative lifetimes of the first-excited singlet state were calculated. It is found that the influence of nonpolar substituted groups of the benzoxazolyl on the radiative and nonradiative rates is unremarkable, whereas the influence of polar substituted groups is remarkable. In phenyl compounds, benzoxazolyl groups enhance fluorescence by increasing the rate of the radiative. In vinyl compound benzoxazolyl decrease the rate of nonradiative deactivation. This phenomena is connected with the configuration change which occurs in.photo-excitation process.
    A New Method foir the Synthesis of 5(4H)-Oxazolones from N-Acyl-a-Amiho Acids
    Huang Huamin, Zhang Jianing, Wang Jingyang
    1990, 11(9):  958-962. 
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    In K2CO3-CH3COCH3-H2O system, N-acyl-a-amino acids (Ⅰa-j) were prepared by the reaction of amino acids with N-acyl thiazolidines-2-thiones and the yields were 76%~95%. The synthesis of saturated 5(4H)-oxazolones(Ⅱa-h) from Iunder mild reaction conditions in yields of 43%~84% by the use of cyanuric chloride as a condensing reagent in the presence of triethylamine was reported. Unsaturated 5(4H)-oxazolones (Ⅲa-j) were obtained from Iin the yields of 43%~93% by the aldol reaction in which Fe2SO4)3 was used as a catalyst.
    A Study on the Chemical Constituents of Volatile Oils by Capillary GC/MS and GC/FTIR
    Chen Yiaozu, Li Zhaolin, Wang Mingkui, Chen Ning, Qiu Ningying
    1990, 11(9):  963-966. 
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    The chemical constituents of volatile oils of Dracocephalum heterophyllum Benth and Gnaphalium multiceps Wall have been investigated by capillary GC/MS and GC/FTIR. The advantage and limitation of the two methods are discussed in this paper.
    Studies on the Synthesis and Spectra of Arylfurylpyrazolines
    Ma Yinmin, Li Zhongjie
    1990, 11(9):  967-971. 
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    In this paper, fourteen new 1-pnenyl-5-(p-dimethylaminophenyl)-3-arylfuryl and -3-aryl-furylethenylpyrazoline derivatives were synthesized. The IR, UV/Vis, FL, MS, 1H NMR spectra were determined. Some discussion was made on the direction of cyclization in the reaction of substituted pentadienone with phenylhydrazine. The photoconductivity and electrochromic property of pyrazo-lines obtained were also studied.
    Preface
    Calculation of A Factors and Activation Energies for the Fission of Hexafluoroethane into Fluoromethyls and Its Reverse Reaction
    Dong Shunle, Ding Shiliang, Deng Conghao
    1990, 11(9):  972-976. 
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    Semiclassical statistics was used to calculate the critical bond lengths and the results obtained were used to calculate Arrhenius parameters for the reaction CF3+CF3C2F6. The values obtained are in agreement with the experimental results.
    Articles
    Spectrometric Investigation of the Types of Forming [Fe2(CO)8]2- and [Fe3S(CO)9]2- ant Studies on Their Electronic Spectra and Electronic Structures
    Niu Shuyun, Guo Chunxiao, Zhang Zhigui, Jin Zhenyan
    1990, 11(9):  977-981. 
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    Three types of clusters were obtained from the reactions of Fe(CO)5 with(Et4N)2MoS4 in CH3OH-CH3ONa solution by using different reactant ratios and different concentrations of the base:(Ⅰ)[Et4N]2[Fe2(CO)8]、(Ⅱ)[Et4N]2[Fe3S(CO)9]、(Ⅲ)[Et4N]3[FeMo2S8O2].Their crystalline structures,UV-VIS and IR spectra were measured.The electronic structures of the anions of (I) and (II) are studied by EHMO method and the analysis and assignment of their electronic spectra are made on the basis of the calculations.The relationship among the types of clusters formed in the three reactions and the change of reactant ratios and concentrations of the base are also studied.
    Preparation and Properties of Pillared Synthesis Mica-Montmorillonite
    Liu Ziyang, Jiang Dazhen, Zhou Qun, Min Enze, He Mingyuan
    1990, 11(9):  982-987. 
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    Pillared synthetic dioctahedral clays (designated SMM) are prepared by introducing hydrox-yl Al oligomer and hydrolysis material of CH3CH2CH2NH2Si(OCH2CH3)3 into SMM layers respectively. X-ray diffraction results show that the basal spacing of Si pillared SMM is larger than that of Al pillared SMM slightly. The Si and Al pillar's length are 0. 86 and 0. 83 nm respectively. According to the value of Si-O bond length, the Si pillar may be the tripolymer of silica.In the studies of DTA, IR, it is found that the dehydroxylation of octahedral hydroxyl group is easier at high temperature calcination because of pillaring. These indicate that bonding between the pillar and the layers may occur.The surface acidities of Si-CLM and Al-CLM determined by pyridine adsorbtion and NH8-TPD show some differences, there are more weak Bronsted acid sites on the former, however, more strong Lewis acid sites on the latter. The total surface acid amounts of the sampales are almost the same.Pillared SMM has a higher activity for cumene cracking and a lower delay rate compared with NH4-SMM. The initial activities of the catalysts are mainly related to the strong acid sites, however, the delay rates seem to be affected by strong Lewis acid sites.
    Investigation of Hydrolysis of Disubstituted Benzonitriles in Aqueous Mediums
    Wang Liansheng, Yu Gang, Han Shuokui, Wang Aiguo, Zhang Zheng
    1990, 11(9):  988-992. 
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    Aseries of hydrolysis rate constants and activation energy of 6 disubstituted benzonitriles were determined at pH 10~14 and 40~80℃ by HPLC. The fate constants of these compounds at 25℃ were obtained by extrapolating. There is a linear relationship between lgkB(kB defined as hydroly-Sis rate constant for base-catalysis) and σ (Hammett Yett substituent constant) in the form of lgkB=1. 45σ-0.859. Also, the relationship between lg kB and pKa(acid constant) was obtained in the form of lgkB=1. 34pKa-4.83.The resurts obtained are significant and useful to predicting the effects of all disubstituted behzoni-triles on the environrnent and can offer some scientific data for the risk-assessment and treatment of these organic pollutants.
    D NMR Studies on the Intramolecular Process of Metal Ions BDTA Complexes
    Yang Daiwen, Song Ruifang, Qiu Zuwen
    1990, 11(9):  993-997. 
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    The D NMR spectra of Mg, Ca and Hg-BDTA(meso-2,3-Butanediaminetetraacetate) complexes were investigated in this paper. The thermodynamic parameters are obtained by the complete line shape analysis and the △S values are explained by the H2O displacement mechanism. It is discussed that the chemistry shift differences of Zn, Cd, Pb, In, Sc, La and Lu-BDTA depend on the temperature.
    The Electrocatalytic Properties of Platinum Single Crystal (210),(310) and (610) Stepped Surfaces in Formic Acid Oxidation
    Sun Shigang(Sun S G), Clavilier Jean
    1990, 11(9):  998-1002. 
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    By comparing the electrooxidation character of formic acid at Pt(210), Pt(310) and Pt(610) with those at Pt(110) and Pt(100), it is found that the electrocatalytic properties for a stepped surface depend not only on the symmetry of the surface sites contained in this surface, but also strongly on the size of the ordered domain of sites with a given symmetry and the surroundings associated.
    Studies on the Corrosion Behavior of ZnAl and ZnAl RE Alloys in NaCl Solution by Electrochemical Method
    Wang Yan, Huang Chubao, Song Renying
    1990, 11(9):  1003-1006. 
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    The variation of corrosion resistance in NaCl solution and hardness of Zn with addition of Al and REwere determined and explained by the-change of microstructure of alloys. The results obtained show that the addition of REand Al increases the stability of Zn in NaCl solution and the hardness of the alloys.
    Synthesis of Gel-Star Polymer by Two Steps
    Yin Rui, Shen Jiacong
    1990, 11(9):  1007-1010. 
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    In this paper, the styrene-isoprene gel-star block copolyrqer with different branching degrees was synthesized by using gel uncleus with pendant vinyl groups to be a crossolinking agent. It was found that divinylbenzene could control the number of vinyl groups which were measured by UV spec-trometry, and chain transfer agent had a serious effect on the molecular weight of gel nucleus. Following crosslinking reaction by GPC, we revealed that increasing the branching degrees was slow step. In order to get higher branching degree, we must consider the'space hinderance and being wrapped of vinyl groups.
    Studies on the Thermal Behavior and Stability of Chlorinated Ethylene-Propylene Copolymers
    Liao Kairong, Lu Zejian, Lin Shangan
    1990, 11(9):  1011-1013. 
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    The thermal behavior and stability of the, title materials (CEP) were studied by means of TMA, DSC, and TG/DTG. The results show that the softening temperature of them is increased with the increase of chlorine content. In the case of the same chlorine content, the CEP with higher content of propylene component has a higher softening temperature and a higher activation energy of dehy-drochlbrination. Their thermal stability can be effectively improved by. adding stablizers in them.
    Studies on Chemical Constituents of Thermopsis Licentiana(I)——The Structure of a New Alkaloid
    Jia Zhongjian, Song Guangze, Liu Zimin
    1990, 11(9):  1014-1015. 
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    Anew alkaloid was obtained from the ethanol extract of the whole part of thermopsis licen-tiana by using silica gel column chromatography. Its structure was established as 13-β-hydroxylther-mopsine by means of IR, MS, 13C NMR and DEPT, 13C-1H COSY, 1H-1H COSYtechnique.
    Determination of Multicomponent System with Principal Component Analysis Method
    Ni Yongnian
    1990, 11(9):  1016-1018. 
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    The Principal component analysis (PCA) method for spectrophotometric determination of multicdmponent system is studied . The vector of each principal component was calculated by using gradually repeating substitution and the concentration of the unknown samples is predicted by the established mathematical model. Two demonstrations of colour reaction system are given and the results of quantitative analysis with PCA are better than those of classical least squares method.
    Syntheses of Some Nitrobenzoyloxyphenyl-Prophyrin Type Compounds
    Han Shitian, Liu Yanqin, Xie Hong
    1990, 11(9):  1019-1021. 
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    This paper reports the syntheses of some new nitrobenzoyloxyphenyl-porphyrin type compounds. The structures of all these compounds have been confirmed by MS, NMR, IR, UV and elemental analysis.
    The Synthesis of Rare Earth 2-Methylphenyl Compounds
    Huang Zuen, Huang Wei
    1990, 11(9):  1022-1024. 
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    Six new rare earth 2-methylphenyl Compounds, which are very sensitive to air and moisture,have been synthesized by the reaction of anhydrous lanthanide chloride with 2-methylphenyl lithium(molar ratio 1 : 3) in benzene solution. The compounds having the formula Ln(C6H4CH3-2)3 (Ln = Ce,Pr,Nd,Sm,Gd,and Er)were characterized by elemental analysis,infrared spectra and mass spectra.
    Quick Determinating TPD Activation Energy by Peak Width Method
    Gong Jian
    1990, 11(9):  1025-1027. 
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    Three equations to calculate activation energy of desorption (Ed) were obtained from Polan-gi-Wagner model and TPD profile,Ed=Rln(N1/N2)nT1T2/ΔT and Ed=0.02T1T2/ΔT1/2 (n=1) or Ed=0.03T1T2/ΔT1/2 (n=2) Ed values can be calculated quickly from TPD peak width ΔT and its corresponding parameters by using the three equations. Comparating with other methods, the results are consistent with each other.
    Electronic Energy Bands of the Conducting Polymer Poly (1,4-dithianaphthalene)
    Zhang Jingping, Zhao Chengda, Wang Rongshun
    1990, 11(9):  1028-1030. 
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    In this paper, the electronic energy bands of the conducting polymer poly(1,4-dithianaph-thalene) (PDTN) in two kinds of configuration are calculated. In the calculation, the polymer is treated as a quasi-one-dimensional system, and the method of EHMO/COis used. The results of the energy bands near the Fermi level and the density states of HOMO and LUMO are shown in Fig. 4,5. For comparison .the electronic energy bands of PPS are also calculated in the same way. The conclusion can be obtained that PDTN and PPS have the similar conductivities, because they have the similar parameters such as band width, ionization potential and net charge.
    A Study of the Dissociation Equilibria of Nitdiotriacetic Acid in Ethanol-Water Mixtures
    Shi Shenghua, Li Tian jin, Hu Yinhua
    1990, 11(9):  1031-1033. 
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    The pHpotcntiometric titration was used to determine the dissociation constants of nitrilotri-acetic acid (NTA) in ethanol-water mixtures. The potassium nitrilotriacetate was titrated by a stan-dard solution of hydrochloric acid to increase the accuracy of the determination. In the method it was assumed that n is a mean number of dissociated proton in calculation of the acid dissociation constants. According to the characteristic of NTA, the values of K1 and K2 were obtained by treating the system as the first two-step proton dissociation equilibrium at a low pH, and K3 as the last step at a higher pH. It is found that the values of K1 and K2 decrease with the increase of ethanol content in the solvent, but the value of K3 is just contrary'to this result.
    Polymerization of Liposomes(Ⅰ)—— Synthesis of Unsaturated Liposome Monomer
    Zhang Liqun, Zhou Hongbing, Zhou Qingzhong, Zhou Qireng, Sun Yanhui
    1990, 11(9):  1034-1036. 
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    Polymerizable surfactant,N,N-diethyl-N,N-bis(octadeca-7,9-[or 9,11] dienoyloxyethyl) ammonium bromide has been synthesized by using bleic acid as the starting material. The procedure is as follows: oleic acid is treated by NBS to form allyl bromide. Then the brominated oleic acid is su-bjected to dehydrobromination in the presence of KOH and n-amyl alcohol. Octadecadienoic acid obtained is reacted with PCl3 to form acyl chloride which is esterified with N,N-diethyl-N,N-bis(hy-droxy ethyl)ammonium bromide at room temperature for 48 h. This new type of polymerizable surfactant may form liposomes under ultrasonic wave irradiation. The average diameter was determined as 600 Å by the light scattering technology
    Synthesis of Schiff-Base Macro-Porous Chelate Resins and Their Adsorption Rule for Metal Ions
    Chen Xingqi, Wu Yaoxun
    1990, 11(9):  1037-1039. 
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    Four macro-porous chelate resins of Schiff base were synthesized and their adsorbabilities for seven metal ions were studied. These resins are poly-N-(3-methoxy-salicylidene) vinyl aniline (PMSVA), poly-N-(2-hydroxy-l-naphthylmethylene) vinyl aniline (PHNVA),poly-N-salicylidene vinyl aniline (PSVA) and poly-N-salicylidene vinyl benzylamine (PSB). It is shown by the experiments that the adsorption properties of the four resins for Cu2+ are satisfactory. In addition, the effects of the structures of the chelate resins on their adsorption properties for the metal ions are discussed and the adsorption rule of the resins for Cu2+ was found. On the basis of the rule, a new method for removing cu2+ selectively from the solution of electroplating nickel was drawn up by using these chelate resins and satisfactory results were obtained.
    Studies on Interpenetrating Polymer Networks of Polyurethane/Polystyrene
    Xue Shuchang, Zhang Zhiping, Ying Shengkang
    1990, 11(9):  1040-1042. 
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    A series of interpenetrating polymer networks of polyurethane/polystyrene (PU/PSt-IPN) were synthesized by a simultaneous method. The. molecular weight,glass transition temperature and mechanical properties of the system were investigated by GPC, DSC and Instron Tester. The results show that the molecular weight of PSt decreases and its distribution becomes wider with increasing the ratio of PU in the system. During polymerization, the faster the molecular weight of the polymer in IPNincreases,the earlier the phase separation of the system occurs. PU/PSt-IPN is an incompatible system. There are two Tg's corresponding to the Tg's of the respective component polymers. The stiffness of the IPN increases with enhancing. DVB content and NCO/OH ratio or PSt ratio. The strain inbreak of the IPNis the largest at the composition ratio of 75/25.