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    24 May 1991, Volume 12 Issue 5
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    Articles
    Synthesis, Characterization and Oxygen Evolving Activity Determination for Mn3O(Salea)2(C2H3O2)3·HC2H3O2
    Song Lu-lin, Chen Ke
    1991, 12(5):  569-572. 
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    The trinuclear manganese (Ⅲ).Schiff base complex Mn3O(Salea)2(C2H3O2)3· HC2H3O2(where salea2-is the dianion of ONO tridenate Schiff base prepared by condensing ethanol amine with salicylaldehyde) was synthesized and characterized by magnetic susceptibilities, molar conductivities, infrared spectra, electronic spectra and thermoanalyses, etc. The measurement of oxygen evolving activity was performed using an oxygen electrode. In the aqueous solution involving p-benzoquinone, the complex can promote water to decompose and liberate dioxygen and this is affected by temperatures and concentrations of p-benzoquinone and the complexs. Apossible equation for oxygen evolving reaction is suggested.
    Synthesis and Structure of p-Dimethylaminophenylgermanium Sesquioxide and Its Effect on the Mitotic Activity of Tumor Cell in Vitro
    Zhang Shu-gong, Ni Jia-zuan, Niu Chun-ji, Nie Yu-xiu, Chen Yu-lan
    1991, 12(5):  573-576. 
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    Under atomospheric pressure, the p-dimethylaminophenylgermanium sesquioxide was prepared. The characters of IR, XPS and TG-DTA show that the synthetic compound is the para-monogermanium substitued product. The sesquioxide possesses a higher polymerization degree than Ge-132.In the cell culture of breast carcinoma in vitro, the mitotic activity of tumor cell was obviously inhibited when the concentration of the compound is over 1. 0 mmol.
    The Coordination Interaction of a-Globulin with Rare Earth Metal Ion Gadolinium (Ⅲ)
    Yang Pin, Ma Gui-bin, Zhao Hong-wei
    1991, 12(5):  577-579. 
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    By using the method of fixing the concentration of paramagnetic metal ion and gradually changing the concentration of α-globulin, the proton relaxation time of solvent was determined, the complexation of a-globulin with gadoliniun (Ⅲ) was studied. The results show that there are three binding sites of Gd(Ⅲ) in a-globulin molecule and the dissociation constant is 2. 5× 10-4mol/L.
    Preparation and Characterization of the Solid Complexes of Rare Earth with 1,5-Bis-(1'-Phenyl-3'-Methyl-5'-Pyrazolone-4')-Pentanedione-[1,5] (BPMPPD) and Cetyl Pyridinium Bromide (CPB)
    LI Xiao-jing, Wan Yan-Hui, Mu Wei-yun, Yang Ru-dong
    1991, 12(5):  580-584. 
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    Thirteen new solid complexes have been synthesized and characterized by elemental analysis, molar conductivity, IRspectra, UVspectra, thermoanalysis, fluorescence spectra etc. The stoi-chiometry of complexes are CP[Y(BPMPPD)2]·5H2O, CP[La(BPMPPD)2] 2H2O, and CP[Ln (BPMPPD)2] (Ln = Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb). The results of ther-moanallysis show that the decomposition temperature of the coordination compounds has the "tetraef-fect". The hypersensitive transition of Pr, Nd, Ho, Er, Tm complexes and characteristic fluorescence of Sm, Eu, Tb, Dy complexes have been studied.
    Studies on Hydrothermal Crystallization of NaZr2(PO4)3
    Yue Yong, Zhou Feng-qi, Lu Jing-cai, Pang Wen-qin
    1991, 12(5):  585-586. 
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    NaZr2(PO4)3was synthesized from Na2O-ZrO2-P2O5systems under hydrothermal conditions. The product was characterized by means of X-ray powder diffraction and infared spectromrtry. The results show that the hydrothermal method is superior to that of the solid state reaction for synthesizing NaZr2(PO4)3.
    Synthesis and Characterization of the Heterobinuclear Transition Metal Complexes of the Schiff Base Derived from 3-Formylsalicylic Acid and Trimethylenediamine
    Zhou Xu-ya, Tao Ruo-jie, Yu Zhao-wen, Jin Dou-man
    1991, 12(5):  587-589. 
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    Copper (Ⅱ)-M(Ⅱ) heterobinuclear complexes of the schiff base derived from 3-formylsali-cylic acid and trimethylenediamine, CuMTS · 2H2O(M = Zn,Co,Fe,Mn, Mg), were synthesized. AHthese compounds were characterized by elemental analysis, IR, UV-visible spectra and room tem-preture magnetic moments. In DMSO, the electrochemical properties of this species were examined by cyclic voltammetry, differential pulse polarography and DCpolarography. The relationship between properties and structures was studied.
    Investigation of the Gradient Effect of Retention Time on the Gradient Coated GC Column
    Yun Xi-qin, Kou Deng-min, Li Yan-hong, Lu Xian-yu
    1991, 12(5):  590-593. 
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    The gradient effect of retention time on the gradient coated GCcolumn is investigated. The theoretical equation is derived. The columns possessing double exponential and exponential/linear gradient in k and l are treated from the viewpoint of gradient effect and the computer programme is given. An example of the use of gradient coated columns is described and the derived equation has been experimentally verified.
    Resolution of Overlapping Neopolarographic Peaks of Two Species
    Wang Yao-guang, Liu Jian-hua
    1991, 12(5):  594-597. 
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    A new method for resolution of neopolarographic two-component peaks by multiple linear regression is presented. The method is based on the linear superposition of neopolarograms. The overlapping waves of two species can be resolved and the concentrations of them can be determined by the standard addition and the multiple linear regression. The principle of the method is simple. Its program is fast when executed. It is shown that the method possesses an acceptable accuracy and high resolution when the simulated data being handled. The method has been verified futher by the application of the method to staircase sweep neopolarography of In3+/Cd2+and Pb2+/Tl+systems.
    Investigations on Polarography with Linearly Changing Potential (XV)--The Adsorptive Complex Wave of Cu(Ⅱ)-L-Adrenaline
    Ding Shi-jia, Zhang Zu-xun
    1991, 12(5):  598-601. 
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    In this paper, the adsorptive-complex wave of Cu(Ⅱ)-L-adrenaline is proposed. In the supporting electrolyte of B. R. buffer solution at pH = 6. 90, the peak potential of the wave is about-0. 246 V(us. SCE). The behaviour of current-potential curve and the machanism of electrode reaction were studied. The rate constant of the electrode reaction (ks), transfer coefficient (α), and the composition, apparent stability constant, dissociation constant of the complex were determined.
    A Study on Kalman Filtering Titrimetric Analysis Method (Ⅰ)--Model for Thermodynamical Equilibrium Titration and Its Aplications
    Li Zhi-liang, Shi Le-ming, Li Meng-long, Yu Ru-qin
    1991, 12(5):  602-603. 
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    In this paper a study on the model for thermodynamical equilibrium titration has been made. The modeling of the state space and measurement process has been studied. The effects of some parameters,such as the sampling interval,model error,and measurement noise etc.,on the filtering and smoothing estimation have also been examined. Anew method for determining the end-point or equal-point was proposed and satisfactory results were obtained for the simulated and practical titration data.
    Frequency-Spectrum Analysis of Oscillopolarogram
    Bi Shu-ping, Qi Hong, Du Si-dan, Gao Hong
    1991, 12(5):  604-606. 
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    Application of frequency-spectrum analysis to oscillopolarogram using Fourier transformation technique is given in this paper. Harmonic equations of E-t curve of the supporting electrolyte are given. Theoretical conclusions are confirmed by experimental results. The Faradic rectification is also explained.The frequency-spectrum can be used in analysis. The second and third harmonic potentials can be used to determine the concentration of the depolarizer. The lowest concentration determined is 1 × 10-6mol/L. The method is more sensitive than the conventional one and the precision is also better. THe factors influencing the frequency-spectrum are studied. The influence of dissolved oxygen on ordinary oscillopolarogram is not obvious but its effect can be seen easily in the frequency-spectrum analysis.
    Studies on the Differential Pulse Adsorptive Stripping Voltammetry of Antimony (Ⅲ)-Gallic Acid Complex
    Li Yi-heng, Yao Wei-kuan, Tang Si-lin
    1991, 12(5):  607-609. 
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    In the 0. 10 mol/Lacetate buffer solution with pH 4.4, a sensitive reduction wave of antimony-gallic acid complex has been obtained at-0. 47 V (vs. Ag/AgCl) using differential pulse voltammetry. The peak current is linearly proportional to the concentration of antimony in the range of 4. 0×10-10to 8. 0×10-8mol/Lafter a 2 min accumulation. The reaction mechanism has been discussed. It is shown that the current is caused by the reductioin of antimony (It) bonded in the complex which is adsorbed on the hanging mercury drop electrode, and that the adsorption of the complex obeys Frumkin isotherm. The proposed method has been applied to the determination of trace antimony in copper alloys with satisfactory results.
    Determination of Rare Earth Element Yttrium by Electrogenerated Chemiluminescence of ADPD
    An Jing-ru, Lin Jin-ming, Xie Zeng-hong
    1991, 12(5):  610-612. 
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    A sensitive method for determination of trace element yttrium (Ⅲ) in a buffer medium of Na2CO3-NaHCO3-(NH4)2C2O4(pH 10.27) is reported based on the electrochemiluminescence of the new reagent 5-(p-aminophenylazo)-2, 3-dihydro-1, 4-phthalazine-l, 4-dione(ADPD). The detection limit of yttrium is 0. 002 ppm,and linear calibration range extends from 0. 01 to 0. 6 ppm. The influence factors and mechanism of the ECL of Y(Ⅲ) catalyzing ADPD emission process are discussed.
    Synthesis of 3-(α-Pyridyl)Propyl Aryloxyacetate and Their Herbicidal Activity
    Fang Jian-xin, Shi Yan-nian, Jia Zhi-fen, Yang Xiu-feng, Dong Guo-hua, Tian Ying-fen
    1991, 12(5):  613-616. 
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    Sixteen3-(α-pyridyl)propyl aryloxyacetates with the formula I (R1and R2is H, CH3, Cl, Br, NO2respectively) have been prepared in four steps. All of them are new compounds.Their chemical structures were confirmed by IR, 1H NMR spectra and elemental analysis. The results of the biological tests showed that 6 and 10 at 75 g/mu treating soil, gave about 80% control of Echinochloa Grus-galli and oats, and 90%-100% control of rape and lucerne.
    Synthesis of Arylpyruvic Acids and Ethyl Arylpyruvate
    Han Ying-lin, Hu Hong-wen
    1991, 12(5):  617-620. 
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    Ethyl arylpyruvates were obtained by hydrolyzing the corresponding ethyl α-formylamino-β-arylacrylates in 5% ethanol-hydrochloride aqueous solution, while arylpyruvic acids were obtained by further treating the ester with saturated sodium carbonate or 20% sodium hydroxide in good yield.
    Open-Chain Crown Ether Analogues (Ⅱ)--Syntheses and Studies of Open Chain Equivalents of Azacrown Ether with End Groups of 4-Oxyantipyrine
    Tang You-gen, Liu Fu-chu, Zhao Yan-lai
    1991, 12(5):  621-624. 
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    Eleven openchain azacrown ether analogues with the end groups of 4-oxyantipyrine (3a-k) were synthesized and identified by elemental analysis and spectral data. Two methods for O-alkylation of 4-hydroxyantipyrine are reported. The phase-transfer catalytic behaviour of the new compunds is studied. It is found that these compounds used either as liquid-liquid or as solid-liquid phase-transfer catalysts have good catalytic activity.
    Studies on Organoarsenic Compounds(XV)--Synthesis of (4-Ethoxycarbonylphenyl)rnethyltriphenylarsonium Bromide and Its Reaction with α,β-Unsaturated Ketones Under Phase Transfer Condition
    Tao Wen-tian, Zeng Wu-zong
    1991, 12(5):  625-627. 
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    This paper presents the synthesis of (4-ethoxycarbonylphenyl) methyltriphenylarsonium bromide(1) and its reaction at room temperature with α,β-unsaturated ketones(2a-r) in the two phase system of CH2Cl2-50% NaOH(aq) to afford the substituted cyclopropane derivatives(3a-f), and the yields are fairly good (80-87%). Their structures are ascertained by elemental analysis, 1R,1H NMR, and MS spectrometry.
    Studies on Friedel-Crafts Alkylation with Liquid Alkenes Catalyzed by Perfluorooctane Sulfonic Acid
    Fu Xiang-kai, Pu Wan-li
    1991, 12(5):  628-630. 
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    The Friedel-Crafts reaction of aromatic compounds with styrene and cyclohexene as the alkylation reagents, and with solid superacid perfluorooctane sulfonic acid (POSA) as the catalyst is reported. The reaction has high yields, simple procedure and is easy to work up. The reaction with styrene as the alkylation reagent gives 100% para-substituted products, and the reaction with cyclohexene as the alkylation reagent also has a high position selectivity. The catalyst POSAcan be reused or recovered, and no waste acidic solution drain off.
    Synthesis of New Type of Organogermanium Sesquioxides and Sesquisulfides
    Bai Ming-zhang, An Feng-long, Sun Li-juan
    1991, 12(5):  631-632. 
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    Fifteen organogermanium compounds were synthesized in this work. They are phenylene bis-(trichlorogermaniumpropanoates) and their sesquioxides and sesquisulfides. Their compositions and structures were tested by elemental analysis, IR and 1H NMR spectroscopy.
    Studies on the Application of Optically Active 2-(4-Chlorophenyl)-3-Methylbutanoic Acid and α-Isopropyl-4-Chlorobenzylamine as Resolving Agent
    Wang Min, Hu Bing-fang
    1991, 12(5):  633-635. 
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    Optically active 2-(4-chlorophenyl)-3-methylbutanoic acid and its degradation product, optically active α-isopropyl-4-chlorobenzylamine were efficiently used for the resolution of racemic bases such as PTE, PEA, erythro-DPAE, and recemic acids such as trans-chrysanthemic acid and as-partic acids.
    Gauss Quadrature Calculation for Two-Centre Overlap Integrals of Slate-Type Orbitals
    Zheng Yuan-qing
    1991, 12(5):  636-639. 
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    The Guass-Legendre numerical quadrature method was introduced into the calculation of STO two-centre overlap integrals. The result shows that this method is efficient and accurate, and it can be applicable to the integer power and non-integer power of r, and to the sufficiently wide range of values of orbital parameters and internuclear distances as well.
    Theory on Approximation Linear Combination of Unit Orbital--The Effect of Terminal Functional Groups on the Electronic Structures of Acetylene Systems
    Ye Yuan-jie, Tang Ao-qing(Au-chin Tang)
    1991, 12(5):  640-643. 
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    The quantum chemistry calculations are carried out on the polyacetylene systems with different terminal functional groups by the approximation method of the linear combination of unit or-bitals(LCUO). The results show that there are two kinds of different terminal functional groups which have different effects on the energy band structure of the polyyne-the halogen has little effect, and the terminal groups containing oxygen and nitrogen have a strong effect that are similar to the doping function.
    Mechanisms of H-H Insertion and Addition of Cumulene Carbene H2CCC:
    Wang Bing-ze, Wang Chen-Jian, Deng Cong-hao
    1991, 12(5):  644-647. 
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    Reactions H2CCC: (1)+H2→CH2CCH2(2)+CH3CCH(3) are studied using HF/3-21Ggradient method. The insertion 1+H2→2 occurs easily in fashion of "end-on" approach with a barrier of about 45 kJ/mol. The addition 1+H2→3 is fulfilled in two steps, the 2+2 addition toethenylenene carbene, then followed by 1,2-hydrogen migration. Because of the symmetry prohibition, the 2+2 addition proceeds via a 3-center transition state with a high barrier, the 4-center interaction occurs in the later stage. The reactions 1+H2are kinetically controlled with 2 as the major product. The requirements for the carbene addition are discussed.
    The Properties and Applications of Valence Shell Excitation n-Electron Wavefunctions with Symplectic Symmetries
    Hu Hai-quan, Liu Cheng-bu, Jin Bei-yan, Sun Jia-zhong
    1991, 12(5):  648-652. 
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    The properties of valence shell excitation n-electron wavefunctions with symplectic symme-tries have been discussed. This kind of wave-functions is suitable for both closed-shell and open-shell systems. As illustrations, the ground states of Li2, LiH2- and CH3+ are calculated. The calculated results show that this kind of wavefunctions is capable of describing electron correlations, and the orbitals obtained from the calculation are all natural orbitals.
    Angular Overlap Model Calculation and Its Simplification
    Zhao Ming, Sun Sui
    1991, 12(5):  653-655. 
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    The formulation is developed by which the values of Group Overlap Integrals(GOIs) between orbitals of the central atom and ligands'orbitals in a coordination compound can be carried out. GOIs whose orbitals are transformed under molecular point groups are rewritten as those only under rotational point groups on condition that there exists a simple relation between the two types of GOIS. The calculations using Angular Overlap Model on GOIs are simplified.
    Effects of Central Atoms on Redox Characteristics of Heteropolymolybdates with Keggin Structure
    Zhang Heng-bin, Wang Guo-jia, Wu Tong-hao, Yan Xiao-bin, Hu Ji, Li Shu-jia
    1991, 12(5):  656-659. 
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    The redox properties of molybdoarsenate, molybdophosphate and molybdosilicate with Keg-gin structure have been studied by electrochemical method. The effect trend of central atoms, arsenic, phosphorus and silicon on the redox characteristics of the heteropolymolybdates was obtained from the experimental results.
    Kinetic Characterization of Electrocatalytic Oxidation of Sulfite at Chemically Modified Electrodes
    Chen Xiao-ming, Bi Yan-feng, He Pei-xin
    1991, 12(5):  660-663. 
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    The oxidation of sulfite at glassy carbon electrodes is sluggish, but the reaction can be catalyzed by Nafion-Os(bpy)32+/3+modified electrode. Saveant-Andrieux theory is used as the diagnostic tool to characterize the dynamics of the catalysis. The substrate concentration and the rotation rate of electrodes are varied systematically in order to evaluate four characteristic currents quantitatively. The kinetic zone diagram is used to assign the kinetic type of the system. As the concentration of the reac-tant varies form 8× 10-5to 1. 28 ×10-3(mol/L), the "SR" dynamic behavior remains. An experimental verification for the theoretical model is also provided.
    Intrinsic Dissociation Constant of Weakly Basic Anion Exchange Resin
    Wang Chang-shou, Tao Zu-yi
    1991, 12(5):  664-667. 
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    The general procedure is developed with which the intrinsic dissociation constants of weakly acidic and basic ion exchange resins can be determined without assuming the activity coefficient of M+(or X-) ion equal to that of H+(or OH-) ion in the resin phase. The procedure is based on the application of the Donnan membrane equilibrium equation and the extrapolation.In this paper, the intrinsic dissociation constant of the weakly basic anion exchange resin D705 was determined, and the water sorption, electrolyte sorption and titration curve of the resin D705 are studied in conjunction with the varying degree of neutralization.
    Localization of Molecular Orbital in EHMO Method
    Qin Yue, Yang Zhong-zhi, Wang Zhi-zhong, Yu Heng-tai, Shen Er-zhong
    1991, 12(5):  668-671. 
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    Using Foster-Boys localization criterion, the problem of localization of molecular orbitals in EHMO method is investigated. We have proposed an approximate approach for calculating two-center orbital integrals of dipole moment. The EHMO localized molecular orbitals obtained in terms of the approximate approach are very close to the accurate ones and qualitatively agree with the results obtained by using ab initio STO-3G method.
    Studies on Transfer Mechanism of Chloroquine at the Aqueous 1,2-Dichloroethane Interface
    Xiao Jun, Lin Song, Nie Li-hua, Yao Shou-zhuo
    1991, 12(5):  672-676. 
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    Transfer processes of chloroquine in aqueous phase, non-ionized chloroquine and chloro-quine existing as ion-pair complex with tetraphenylborate in organic phase across the aqueous 1,2-CH2C1CH2C1interface were studied by polarography with the electrode of drop electrolyte (EDE), cyclic voltammetry with current scanning and chronopotentiometry, respectively. Their transfer mechanisms were proposed. The effect of pH of aqueous phase, the concentration of chloroquine and the flow-rate of EDE as well as the scanning rate on transfer behavior was discussed. The interfacial potential difference and Gibbs transfer energy were calculated as ΔDCEWφ=0. 06 V, ΔGtruo,DCE→W=-11. 58 kJ/mol, respectively.
    Enumeration of Isomers of Substituted Adamantane
    Gu Fang-zhi, Wang Jian-ji
    1991, 12(5):  677-680. 
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    In this paper, the graph-theoretical method is used to enumerate the numbers of configurations, chiral and achiral configurations of the adamantanes substituted by the same atoms and the adamantanes substituted by alkyls. Some results are tabulated.
    A Quantum Chemical Investigation of Activity Order of Coordination Catalysis of Transition Metals (Ⅱ)--Activation of Dinitrogen
    Zheng Yuan-qing
    1991, 12(5):  681-683. 
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    The catalytic activities of transition metals for the activation of N2were studies by quantum chemical method, combining HMO with EHMO and CNDO. The results obtained are in agreement with experimetal data, and indicate that side-on coordination of N2on transition metals is better than that of end-on and was proved by experimental facts indirectly.
    A Study on Factors Affecting the Properties of Fe3O4Ultrafine Particles
    Kang Hong-ye, Wang Yun-jun, Shi Zhan, Yu Chun-man, Zhao Mu-yu
    1991, 12(5):  684-685. 
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    The magnetic properties of Fe3O4ultrafine particles prepared by chemical coprecipitation are closely related to the mixing process of precipitators, the concentrations of the solution and the molar ratios of Fe2+/Fe3+/OH-, etc. We have improved the method of the chemical coprecipitation and found that there are an obvious increase in the magnetic properties and crystal degree and an obvious decrease in the size of Fe3O4ultrafine particles.
    Studies on Kinetics of CO Substitution of M(CO)5(M=Fe,Ru,Os) in the Presence of (CH3)3NO
    Shen Jian-kun, Gao Yi-ci, Shi Qi-zhen, Fred Basolo
    1991, 12(5):  689-688. 
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    In this paper the kinetics for COsubstitution by PPh3of M(CO)5(M=Fe,Ru,Os) in the presence of catalytic promoter, (CH3)3NO is reported. The rates of reaction are first-order in concentrations of M(CO)Sand of (CH3)3NO but zero-order in PPh3concentration. The reaction rates show an approximate overall four-fold increase in the order Fe < Ru < Os. This is a contrast to the roughly fourty-fold decrease in rate in the order Fe > Ru > Os for the corresponding metal carbonyl cluster, M3(CO)12.
    Effect of Cu, K Promoters on Adsorption-Desorption Characteristics of Iron-based Catalysts
    Wu Ai-ping, Wang Qi
    1991, 12(5):  689-691. 
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    Steady-state chemisorption and TPDwere used to study adsorption-desorption characteristics of CO and H2in F-Tsynthesis over Cu, Kpromoted iron-based catalysts, the effect of Cu, Kpromoters was discussed in detail.
    Studies on Adsorption Properties of Dealuminated Mordenites
    Zhu Gui-hua, Zhong Ai-lian, Hu Jia-fen, Li Quan-zhi
    1991, 12(5):  692-694. 
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    The adsorption isotherms of benzene, cyclohexane, p-xylene, m-xylene and o-xylene on HM at 50℃ were determined by vacuum gravimetric method. The order of limiting adsorption on HM (silica-alumina ratio was 15. 8) is benzene>p-xylene>cyclohexane>m-xylene>o-xylene. The adsorption isotherms of benzene and cyclohexane on dealuminated mordenites(silica-alumina ratios were 15. 8, 22. 3, 59. 7, 185. 6) at 50 show that the limiting adsorption of benzene and cyclohexane all decreased with the increase of silica-alumina ratios.
    Preparation of Enzyme Carriers with Regulated Solubility and Studies on Immobilized Enzyme
    Li Zeng-ji, Shen Jia-cong, Ma Lin, Cheng Yu-hua
    1991, 12(5):  695-698. 
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    The methacrylic acid-acrylamide-maleic anhydride copolymers were prepared by radical precipitate copolymerization in dioxane. The copolymers exhibit the property of reversible precipitation-solubility changes due to their macromolecular complexes formed by hydrogen bonds when the pHvalues of the solution were changed. The immobilization of papain was carried out by using the copolymer as a carrier without other coupling agents. The immobilized papain shows the insoluble form below pH 3. 8 and soluble form above pH 3. 9. The immobilized papain with the advantages of soluble and in-soluble enzyme was obtained.
    A New Initiator for Group Transfer Polymerization--3-Ethoxy-3-Trimethylsiloxy Acrylonitrile
    Xia Hai-ping, Zou You-si, Pan Rong-hua
    1991, 12(5):  699-702. 
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    The group transfer polymerization (GTP) is a new technique for polymer synthesis. In this paper, Anew GTPinitiator:3-ethoxy-3-trimethylsiloxy acrylonitrile (ETSAN) is reported. It can be synthesized easily:IR,MS,1H and 13CNMR data of ETSAN are reported. The new initiator has a high initiation reactivity. When it initiates acrylonitrile monomer, an explosive polymerization can be observed usually.
    Studies on a-Amylase from Bacillus Subtilis 86315(Ⅰ)--The Thermal Stability of a-Amylase
    Shi Yong-chang, Jiang Yong-ming, Sui De-xin, Wu Yan
    1991, 12(5):  703-706. 
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    The thermal stability and the fluorescence spectra of α-amylase from bacillus subtilis 86315 are studied in this paper. The enzyme is stable below 50℃. Heated at 70℃ for 10 min the enzyme loses its all activity, at the same time, a considerable change of its fluorescence spectra was observed. The α-amylase in the solution including 0. 02 mol/L CaCl2and 0. 02 mol/L NaCl retains its activity on heating at 70℃ for 10 min, and its fluorescence spectrum is close to that of the native enzyme. The experimental results show that a proper ratio of CaClz to NaCl could stabilize the conformation of a-amylase, thus raising its thermal stability greatly.
    Ionic Conductivity of the Complexes Formed by Poly(Tetramethylene Succinate) and Various Alkali Metal Salts
    Huang Fa-rong, Wang Xue-qiu, Li Shi-jin
    1991, 12(5):  707-709. 
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    The properties and structures of the complexes formed by poly (tetramethylene succinate) and various inorganic alkali metal salts are investigated in the present article. The solubility of a salt in the polyester concerns its lattice energy and melting point. The higher the lattice energy and melting point of a salt, the lower the solubility of the salt in the polymer. The properties and dissolution ability of a salt can affect the conductivity of the electrolyte. The less the size and the more the number of ions, the higher the conductivity. The conductivity of the electrolytes is mainly related with the electric conduction in the amorphous regions of the polymer. The conductive behavior of the complexes could not be described by Arrhenius equation based on the classical theory or WLFequation on free volume theory.
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