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    24 March 1991, Volume 12 Issue 3
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    Articles
    Syntheses and Properties of Ternary Complexes of Rare Earth Elements with 1'-Phenyl-3'-Methyl-5'-Oxopyrazole-4'-Formylmethanoic Acid and 1,10-Phenanthroline
    Li Xiao-jing, Xing Ya-cheng, Dong Wen-ji, Wang Ya-hong, Yang Ru-dong
    1991, 12(3):  285-289. 
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    The coordination reactions of rare earth elements with 1'-phenyl-3'-methyl-5'-oxopyra-zole-4'-formylmethanoic acid and 1, 10-phenanthroline have been studied by electric conductance titration. Thirteen new solid ternary coordination compounds were synthesized and characterized by elemental analysis, infrared, ultraviolet, proton magnetic resonance and thermogravimetric analysis. Their composition were proved to be RE2L3P2·nH2O, where REare rare earth elements except Sc, Ce,Pm, Lu: Lis 1'-phenyl-3'-methyl-5'-oxopyrazole-4'-formylmethanoic acid, Pis 1, 10-phenanthroline, n=4～6. 0n the basis of all above investigation, it can be concluded that these complexes belong to binuclear structure.
    Synthesis and Molecular Structure of Mixed Thiocyanate and Nitrate Neodymium Complex with Dibenzoylsemicarbazone
    Huang Ling, Huang Chun-hui, Ren Jing-qing, Xu Guang-xian, He Cun-heng
    1991, 12(3):  290-294. 
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    Following the neodymium perchlorate complex with a new Schiff base diben-zoylsemicarbazone, [Nd(C16H16N6O2)2(H2O)2](ClO4)3, another neodymium mixed-coordinated thio-cyanate and nitrate complex [Nd(C16H16N6O2)(NO3)(NCS)2H2O] 3CH3(CO)CH3with the same lig-and was synthesized. Compared with neodymium perchlorate complex, only one chain ligand takes part in the coordination. The excess coordination sites are satisfied by two thiocyanate ions, one ni-treate ion and one water molecule. The C. N. of neodymium is 9. The crystal structure of this complex was determined as follows: P1 space group. The cell constants are:α=10.866(2)Å, b=13. 687(3)Å, c=15.133(3)Å, α=98. 75(4)°,β=107. 64(5)°,γ=112. 14(5)°. The final deviation factor R=0. 075. The electronic structure of model molecule for this complex has been calculated by INDO method. The result shows that coordination bond formed by NCS-is much strongerthan that formed by group. It should be due to the fact that besides σ coordination bondthere isπd interaction be ween NCS-and Nd(Ⅲ).
    Ternary Complexes of Light Rare Earths with B-15-C-5 and Bipyridyl
    Yang Rui-na, Zhu Wen-xiang, Zhao Ji-zhou, Luo Bao-sheng, Chen Liao-rong
    1991, 12(3):  295-298. 
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    Six ternary complexes of rare earth (Ⅲ) nitrate (Ln=La-Eu) with benzo-l5-crown-5 and 2,2'-bipyridyl were prepared. They have the general formula of Ln(NO3)3·bipy·2H2O·B-15-C-5. Their physico-chemical properties have also been studied with conductance, thermal analysis and 1Rspectrometry.The crystal structure of La(NO3)3·bipy·2H2O·B-15-C-5 was determined. The crystal is monoclinic, with space group P21/n. α=11. 951 (6)Å, 6=18. 181(7)Å. c=14. 754(5)Å; β=96. 19(3)°, V=3187. 0Å3, Z=4, Dc=1. 637 g/cm3. The final Ris 0. 035. In the title complex, two nitrogen atoms (from bipy) and eight oxygen atoms(six from nitrate anions and two from water molecules) coordinate to central ion La(Ⅲ) forming an irregular coordination polyhedron. The B-15-C-5 molecule is bound to a water molecule through hydrogen bonding.
    Studies on Synthesis and Characterization of Guanidinium Salts of Lanthanides-Hctcropolytungstosilicate
    Zhai Ying-li, Chen Xiue-nian, Tan Min-yu, Wang Qiu-ying
    1991, 12(3):  299-303. 
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    Potassium salts of lanthanides-heteropolytungstosilicate,LnL, were synthesised in weak basic solution in the presence of Ln3+(Ln=La, Pr. Nd, Sm-Yb). Then,they, were turned into their guanidinium salts, (CN3H6)5[LnSiW11O39] nH2O, by the way of metathesis reaction. It is shown that Ln3+is in the inner-coordination sphere according to the resuluts of cation exchange. The guanidinium salts of lanthanides-heteropolytungstosilicate were characterized by IR,UVspectra, DSC-TGA and X-ray powder diffraction.
    Synthesis and Characterization of SAPO-5 Molecular Sieve
    Zhao De-qing, Pang Wen-qin, Yao Xiu-qin, Qiu Jian-qing, Ye Zhao-hui
    1991, 12(3):  304-306. 
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    SAPO-5 molecular sieve was synthesized by hydrothermal crystallization at 190℃ from a mixture containing HFand tripropylamine as the template. SAPO-5 molecular sieve was characterized by means of XRD, 29SiMAS NMR and electron microprobe analysis technique. The factors having influence on the synthesis have been studied such as the source of P,A1 and Si; composition of starting-mixture; order of adding reactant; pHvalue; F-and template and so on.
    Determination of Component Concentrations in Mixtures of Acids by Factor Analysis
    Ke Yi-kan, Hao Yu-dong
    1991, 12(3):  307-310. 
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    A general expression of the relation among the component concentration, the volume of titrant and the solution pHin mixtures of several acids is derived under the fixed pHtitration condition. The expression is well suited to solve this equation by multivariate analysis methods.In this paper a mixed acid analysis is investigated by factor analysis. Several mixed systems were testified with satisfaction, the method is more reliable and simple.
    The Voltammetric Behaviour of Co (Ⅱ)-DMNH-NO2System and Its Analytical Application
    Xu Hong-ding, Liu Zai-xin, Zhang Li-jun
    1991, 12(3):  311-314. 
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    A sensitive catalytic wave can be obtained in Co(Ⅱ)-DMNH(1,2-dimethyl-2-nicotinic hy-drazone ethyleneoxime)-NO2-system (pH=9). The voltammetric behaviour of this system is studied in this paper. Acompound NH4Co(DMNH)(NO2)2was adsorbed on the surface of hanging drop mercury electrode at-0. 70 V(vs. SCE). In cathodic scanning, NO2-could be reduced catalytically by it at -1. 0 Vand produced a catalytic wave. If hydroxyamine exists in above base solution, the catalytic wave is also obtained, but the optimum acidity is shifted from pH 9 to 8. 2. Using latter system, the content of cobalt in biological samples was determined by adsorptive stripping voltammetry. The results of analysis were satisfactory. The detection limit of cobalt is 1×10-10mol/L.
    The Fluorescence Properties of Tb(Ⅲ)-BPMPHD-CTMAB System and Its Analytical Applications
    Xing Ya-cheng, Yan Lan, Liu Hai-xin, Yang Ru-dong
    1991, 12(3):  315-318. 
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    In this paper, the fluorescence properties of Tb(Ⅲ)-BPMPHD-CTMAB have been investigated. The stoichiometry of fluorescence and the influence of some factors on the system are discussed. Anew method for determination of Tb(Ⅲ) in this system is developed. The detection limit was observed to be 3. 0×10-11mol/L. Satisfactory results were obtained by the proposed method for determination of trace amount of Tb in several synthetic samples.
    Studies on the Cs Source Used in Thermionic Detector for Gas Chromatography
    Wang Qing-fan, Liu Jun, Sun Xun-yun
    1991, 12(3):  319-321. 
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    A new alkali-ceramic Cs source used in the thermionic detector for gas chromatography was made . Acomparison between the sensitivity of rubidium bead and that of caesium bead for alkali-compounds of eguivalent density is made. The response of the bead to different concentrations of Cs and the effect of the heating current are also discussed.
    Investigation on Pulse Polarography (Ⅰ)--The Equation of the Normal Pulse Polarography for the Reversible Wave Influenced by Adsorption
    Zhang Jian-rong, Zhang Zu-xun
    1991, 12(3):  322-325. 
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    The equation of the normal pulse polarography for the reversible wave and its current--potential characters influenced simultaneously by the adsorption of both reactants and products are presented and discussed in this paper. The results obtained are the same as those calculated by numerical imitation.
    The Equations of i-t Curves for Reversible and Irreversible Processes
    Zhang Zu-xun
    1991, 12(3):  326-328. 
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    The equations of i-t curves on single drops for reversible and irreversible processes are described. The experimental results obtained in literatures are in good agreement with the theoretical conclusions . The standard heterogeneous rate constant (ks) values are calculated from the theoretical e-quation by using the experimentally determined values of β'.
    Determination of Trace Nitrite by Single Sweep Polarography
    Gao Zhi-qiang, Li Pei-biao, Zhao Zao-fan
    1991, 12(3):  329-331. 
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    In acidic medium(pH=2), there is a well-defined single sweep polarographic wave of nitrite complex containing NO which can be used for determining trace nitrite. The complex can be strongly adsorbed on the surface of the mercury electrode, the polarographic wave is attributed to the reduction of NOin the adsorbed complex compound to hydroxylamine. The linear range of the polarographic wave is from 1×10-8to 8×10-7mol/Land the detection limit is 5×10-9mol/L. Most common ions show no or a little effect on the determination. This method is applied to the analysis of water, foods and nitrate samples.
    Synthesis of 2-(Trimcthoxyphenyl) Tryptamines Hydrochloride
    Qiu Yu-zhu, Hang Chao, Zhang Zheng, Hu Hong-wen
    1991, 12(3):  332-335. 
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    In the presence of PPA, 2-( 2, 3, 4-trimethoxyphenyl) indole ( 1a) and 2-(3,4,5-trimethoxyphenyl) indole (1b) were prepared by the Fischer synthesis from the corresponding trimethoxyacetophenone phenylhydrazones. 2-(2, 4, 6-Trimethoxyphenyl)indole(1c) was prepared by treating 2, 4,6-trimethoxy acetophenone phenylhydrazone with anhydrous zinc chloride. 1a, 1b, 1cwere converted to the 3-formyl derivatives 2a, 2b, 2Cunder Vilsmier reaction conditions, respectively, and 2a, 2b, 2Cwere condensed with nitromethane to give the corresponding 3-(2-nitroethenyl)in-doles 3a, 3band 3C. Reduction of 3aor 3bwith LiAlH, gaves the corresponding tryptamines 4aand 4b, respectively.
    Studies on the Synthesis of Amino Acids ( Ⅸ)--Solid-Liquid Phase Transfer Catalystic Condensation of 1,4-Diacetylpiperazine-2, 5-dione with Aldehvdes
    Zhou Xiao-ming, Shi Yao-zeng, Du Zheng-ming, Hu Hong-wen
    1991, 12(3):  336-339. 
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    In this paper, we study the condensation of 1,4-diacetylpiperazine-2, 5-dione (2) with aldehydes (3a-n) in the presence of Solid-liquid phase transfer catalytic conditions. Fourteen compounds of (Z)-1-acetyl-3-arylidene(alkylidene)-piperazine-2, 5-dione (4a-n) were synthesized. The configuration of products were discussed.
    Research on Vinylene Inserted Oxazoles--The Syntheses and Opticall Properties of Trans-1,2-bis[2'-(5'-Substituted Phenyl Oxazolyl)]ethylene
    Gao Zhen-heng, Zhang Wen-qin, Wang Ming-zhen
    1991, 12(3):  340-343. 
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    Trans-1, 2-bis[2'-(5'-phenyl oxazolyl)]ethylene(POEOP) and eleven of its substituted phenyl derivatives were synthesized. The relationships between the constitution of those compounds and their IR, UV, FLspectra, fluorescence quantum yields, laser conversion efficiencies were discussed.
    Synthesis of 1-Hydrocarbyl-1-Silacyclobutane and Studies on the Relationship Between the Si-H Stretching Vibration and Molecular Structure
    Yu Kai, Piao Sheng-xun, Zhou Xiu-zhong
    1991, 12(3):  344-346. 
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    The 1-hydrocarbyl-1-Silacyclobutanes. HRSiCH2CH2CH2(R=H, Me, Et, i-Pr, Cyclo-hexyl, CH2Ph, Ph, p-MeC6H4, p-ClC6H4, w-MeC6H4m-ClCH4, Mesityl) were synthesized by the reaction of 1, 1-dichloro-1-silacyclobutane with LiAlH.,. The structure of 9 new compounds were characterized by 1HNMR, 1R and MS. The relationship between the Si-Hstretching vibration and the electronic and steric effects of substituents on the atom Si was discussed.
    New Method for Synthesis of Organogermanium Sesquisulfides
    Sun Li-juan, An Feng-long, Bai Ming-zang
    1991, 12(3):  347-348. 
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    Anew method for synthesis of organogermanium sesquisulfides has been studied in this work. Using this method eight sesquisulfides were synthesized. Five of them are new compounds. Their compositions and structures were characterized by Elemental-Analysis, 1R and 1HNMR spec-troscopy.
    Studies on Carbohydrates (Ⅲ)--Phase-Transfer Catalyzed Synthesis of I-O-acyl-β-D-Glucopyranose Tefraacetates
    Yu Cheng-fang, Liu Ze-fu, Cai Meng-shen
    1991, 12(3):  349-350. 
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    2,3,4,6-Tetra-O-acetyl-α-D-glucosyl bromide reacts with carboxylic acids in the presence of phase transfer catalysts to give carbohydrate esters. There are many advantages in this method, such as good yields, mild reaction conditions and high stereospecificity. The results conclusively disproved a report by Inch and his co-workers that the phase-transfer method requires a nonparticipating group at C-2 or C-6 in the carbohydrate moiety.
    The Selective Electrical Oxidation of Alcohols Under Phase Transfer Catalysis
    Huang You, Li Zhi-hong, Wang Gui-lan, Cai Kun
    1991, 12(3):  351-352. 
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    The Cr(Ⅵ)/Cr(Ⅲ) as an indirect redox system to oxidate of alcohols is studied by means of indirect electrical oxidation under phase transfer catalysis. The experimental results show a better selectivity for oxidation of benzyl alcohols by using this method.
    A Theoretical Study of Reactivities and Atomic Valences of Bridged Boron Compounds
    Cao Yang, Wang You-liang
    1991, 12(3):  353-355. 
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    In this paper, 3-2 IG ab initio calculations are performed on B2H6and its substituted derivatives of bridged atoms H2B2X2(X=F, Cl, OH, NH2, CH3), these geometries are optimized with the energy gradient technique. According to the quantum chemical definition of atomic valence, the valences of bridged atoms are calculated to study the characteristics of bridged bond B-X-B, Some bridged boron hydrides B4H10, B5H9, and B5H11are also calculated to discuss the atomic valences and reactivities of bridged atoms.
    Ab initio Study of Ring Opening and 1,2-H Shift of Methylcnecyclopropylidenc
    Wang Bing-ze, Deng Cong-hao
    1991, 12(3):  356-360. 
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    Isomerizations of methylenecyclopropylidene were studied using ab initio gradient method. The ring opening occurs via a Huckel aromatic transition state. It is a 2 e reaction before the transition state and a 4 e one thereafter, obeying Huckel 4n+2 and 4n rules, respectively. The 1,2 Hmigration occurs by the attack of the carbene p orbital on the shift hydrogen. The ring opening barriers is 24 kJ/ mol, and the hydrogen shift barrier is 118 kJ/mol, at the RHF/6-31G**//STO-3G level. Relative to the ring opening of cyclopropylidene, the substitution results in a larger reactivity but does not change the type and the mechanism of the reaction.
    Theoretical Studies on Spin Hamiltonian of Transition Metal Complexes
    Ba Xin-wu, Li Bo-fu, Sun Jia-zhong
    1991, 12(3):  361-364. 
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    By means of the irreducible tensor method, a theoretical approach to the spin Hamiltonian of transition metal complexes involving the spin-orbit interaction, spin-other orbit interaction, Fermi interaction, magnetic spin-spin interaction and external magentic interaction is proposed. The parameter of the spin Hamiltonian, expressed in the molecular parameters is obtained. Under approximation of atomic orbital, the g-factor of ruby is calculated and the result is in good agreement with the experiments.
    Studies on Electronic Structures and Spectra of Ni Tetraphenylporphyrin
    Wang Zhi-zhong, Li Jun, Feng Ji-kang
    1991, 12(3):  365-367. 
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    We have calculated the electronic structures and spectra of Ni tetraphenylporphyrin using an INDO/CImethod. The MOenergy levels show that for both plane and perpendicular configurations and there exists a large energy gap between the n orbitals of HOMO (a1w, andα2w.) and the next higher occupied level. The calculations on the spectra of lower energy transitions indicate that the calculated values of the lowest Qand Bbands are in good agreement with the experimental date and those of higher Land Nbands are larger than the experimental date. At the same time, the calculated (nπ*) band appears in the range of 37000 cm-1.
    Studies on Dealuminated Faujasite Zeolites (Ⅳ)--Catalytic Cracking of Cumene
    Xu Guo-lin, Xu Heng-yong, Sun Xi-xian, Tian Ying, Zhang Ying-zhen, Zheng Lu-bin
    1991, 12(3):  368-372. 
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    The cumene cracking activity on dealuminated faujasite zeolites was studied by using the pulse microreactor-chromatographic technique and correlated with their acidity which was measured by pyridine poising experiment under reaction conditions. It was shown that the cumene cracking activity on faujasites increased with increasing dealumination and reached a maximum at the Si/Al ratio 5. 38, then decreased with the Si/Al ratios increasing. While the active sites for cumene-cracking were decreased monotonously under reaction conditions, but were decreased slowly at a low dealumination. The rate constant k from kinetic research and the number of strong Bronsted acid sites changed in a similar peaky curve pattern. The maxima of two curves were on the same sample with Si/Al ratio about 8. 87.
    The Standard Enthalpy of Formation of Molybdenum Trioxide Determined by Solution Calorimetry
    Liao Li-fu, Zhang Ping-min
    1991, 12(3):  373-376. 
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    The standard enthalpy of formation of MoO3was determined by solution calorimetry in an automatic RD-1 model heat-conducting calorimeter. The calorimetric solvent is a alkalescent solution consisting of KIO4and KOH. For the solution three different thermochemical cycles were designed to determine the enthalpy. According to the results obtained, the value ΔHt(moO3)0(298.15K)=-765.0±6.8kJ·mol-1 was recommended.
    The Effect of SDS and PVP on the Stability of Agl Sols
    Ma Ji-ming, Wu Guang-wei
    1991, 12(3):  377-380. 
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    The stability of Agl sols in SDS, PVPand their mixed solutions has been studied. The addition of SDSincreases the stability of Agl sols mainly by the increase of zeta potential of Agl particles due to the adsorption of surface active anions on particle surface. The Agl sols are sensitized at low PVPconcentration, and become stable through the steric stabilization of the adsorbed layer at high PVPconcentration. In the mixed solutions of PVPand SDS, the stability of Agl sols is enhanced markedly. This synergistic effect of PVPand SDSon the stability of Agl sols was discussed in terms of the interaction between polymer and surfactant at solid/liquid interface.
    Activity and Kinetics Study on Pt/HM, Pd/HM Catalysts for Oxidation of CO
    Zheng Xiao-ming, Lu Bo-sheng, Hong Qing-mei, Jing Wei-jun
    1991, 12(3):  381-385. 
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    Activity and kinetics for oxidation of COon Pt/HM, Pd/HMcatalysts have been studied, and the kinetic equations have been obtained. The variation of COoxidation activity have been examined at different atomsphere. The effects of promoter Co2+, V5+have also been examined. These results have been interpreted by the catalyst group structure corresponding model.
    Thermodynamic Properties of Aqueous Solution of Sodium Tetraphcnylborate
    Zou Li-zhuang, Li Lin-wei, Wang Xiao-ling
    1991, 12(3):  386-389. 
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    Activity coefficients and osmotic coefficients of sodium tetraphenylborate in the aqueous solution with different concentration were measured in the temperature regions of 288. 15-318. 15 Kby the isopiestic method. The results show that the logarithms of activity coefficients of sodium tetraphenylborate have a linear relationship with temperature. Furthermore, the excess Gibbs free energy, relative partial molar enthalpy, relative partial molar heat capacity of sodium tetraphenylborate are calculated. The formula used to estimate the values of thermodynamic functions of sodium tetraphenylborate are given by the curcve fitting on microcomputer.
    Effect of Some Ligands on Oxidation-Reduction Characteristics of Tetranuclear Molybdenum Clusters
    Zhang Heng-bin, Sun Chun-ting, Huang Qi-jun, Zhang Hong-jie, Liang Tian-fei
    1991, 12(3):  390-393. 
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    Three kinds of tetranuclear molybdenum clusters with the same cluster core and different ligands were studied by cyclic voltammetry. Their formulae are Mo4(μ3-O)2O4Cl2(p-ClC6H4COO)6, Mo4(μ3-O)2O4Cl2(p-NHCOCH3C6H4COO)6and Mo4(μ3-O)2O4Cl2(o-NHCOCH3m-NO2C6H3COO)6.It is concluded from the experimental results that the clusters with the same cluster core have a very similar cyclic voltammogram, and the differences between the peak potentials are related to the electron effects of the substituents of ligands.
    Studies on the Properties of Bi2O3-Al2O3Type Promotors
    Du Yao-guo, Cui Xiang-hao, Wang Bao-hui, Ma Ying-de
    1991, 12(3):  394-396. 
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    Aseries of alumina-supported promotors Bi2O3/Al2O3were prepared by the methods of the impregnation and the decomposition of their corresponding salts. The catalytic activities of CO oxidation and coke-carbon, and sulfur-resistant of the promotors were investigated. The results show that the promotors are close to Pt/Al2O j in the catalytic activities and sulfur-resistant at about 600℃. It is expected that the Pt/Al2O3is used as the promotors for the catalytic cracking in the regeneration of zeolite catalyst, in which it can enhance the combustion rate of coke and decrease the percentage of CO in tail gases.
    The Hydroisomcrization Nature of Nickel-Substituted Mica Montmorillonite and Its Silica Oligomcrs Filtered Clay in Hexane Reaction
    Liu Zi-yang, Jiang Da-zhen, Cai Hui, Cai Hong-wei, Min En-ze
    1991, 12(3):  397-399. 
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    Synthesis of nickel-substituted mica-montmorillonite (NiSMM) was carried out by hy-drothermal mathod. NiSMM was crosslinked with NH2C3H7Si(OCH3)3to yield thermally stable clay (PNiSMM). The hydroisomerization of n-hexane on Pd-impregnated and PNiSMM was observed.It was found that the catalysts reduced by H2at 386℃ are highly active for the isomerization. New strong Bronsted acid sites are formed and strong Lewis acid sites are consumed during the reduction of the catalysts. These facts imply that the highly acidic Bronsted sites are perhaps responsible for the high isomerzation activity. The amount of Pd-impregnated on the catalysts is relative to the activity and the selectivity. This fact implies that the nature of the cluster composed of Ni and Pd atoms seems to be correlative with the properties of the catalysts if metal sites are responsible for the dehydro-genation of alkane.
    Preparation and Characterization of LB Film of Ni(Ⅱ) Complex of 5-(p-hydroxyphenyl)-10,15,20-tris(p-methoxyphenyl)porphyrin
    Yang Kong-zhang, Liu Yan, Feng Xu-sheng, Dong Yu-lin
    1991, 12(3):  400-402. 
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    The Ni(n) complex of 5-(p-hydroxyphenyl)-10,15,20-tris(p-methoxyphenyl)porphyrin was prepared. The composition and structure of the complex were identified by elemental analysis, UVand 1R spectrometry. The thermostability of the complex was determined with thermogravimetry. The procedure of deposition and influence of pHon the formation of the films were also studied. The uniformity of the films was varified by angle resolved XPS spectra. The difference of spectra(UV-Vis) of molecules in LBfilms and in the solution was indicated. The crosswise resistance of monolayer films was determined.
    A Conductometric Study on K+-Mesomorphic Crown Ether Complexes in CH3CN+CHC13
    He Yu-e, Hu Chang-zhong, Chen Shao-qian, Xie Ming-gui
    1991, 12(3):  403-405. 
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    The complex constants Ktfor 1 :1 complexes of KC1O4with cholesteryloxy-carbonyl mesomorphic crown ether compounds derived from DB-18-C-6 and B-15-C-5, i. e. cis(trains)-4, 4'-bis-[(N-cholesteryloxy-carbonyl) amino]-dibenzo-18-crown-6-(C-l and C-2), 4'-[(N-cholesteryloxy-carbonyl) amino]-benzo-15-crown-5(C-3), were determined at 25℃ in CH3CN+CHCl3conducto-metrically. The results show that the complex behaviour of K+ toward crown ether compounds depends on the solvability and ring hole size of macrocyclic polyethers. The lgKtof K+toward C-l, C-2 and C-3 in CH3CN+CHCl3are 5. 56±0. 03, 5. 77±0. 02 and 4. 85±0. 02, respectively.
    EM Study on Polycrystalline CdTe Electrodeposited Thin-Film
    Guo Qing-song, Zhang Li
    1991, 12(3):  406-408. 
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    Astudy of micro-structural marphologies of CdTe thin-film from different technological processes is carried out with SEMand TEM. The change of crystal during the deposing processes was observed, and a comment for mechanism of crystal growth is given. The preliminary results are; (1) Both anode, change of electrolyte composition and rectification of electrodeposited current can possibly decrease the cathodic polarization of CdTe electrodeposited processes. So the surface of 3#CdTe film has a closer texture than that of 1#and 2#; (2) The crystallite size of 3#deposited from electrolyte Bafter annealing in argon and heating in air can be increased to 0. 4-0. 5μm; (3) It is found that CdTe twin crystal exists in the CdTe polycrystallites from the cathodic deposition after annealing in argon and heating in air. The close texture, big crystal and twins-are very advantageous for the improvement of solar-cell.
    Studies on the Mass Transfer Rate of Aromatic Amino Acids on Adsorption Resins
    Tao Xue, Wang Shou-ting, Wang Bu-sen, He Bing-lin
    1991, 12(3):  409-412. 
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    A new method was established to detect the mass transfer rate of aromatic amino acids (Phe and Tyr) on the porous adsorbent. According to Boyd' s equation model, the effective interdiffusion coefficients of amino acids were determinated. The relationship between the adsorbent structure and the rates of diffusion of aromatic amino acids was studied. The effects of temperature and pHon the diffusion rate were also investigated.
    Compatibility Effect of P(MMA-MAA)/PEO Intermacromolecular Complex Through Hydrogen Bonding
    Wang Qi, Xu Xi
    1991, 12(3):  413-416. 
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    Aseries of poly (methyl methacrylate-methacrylic acid)/poly (ethylene oxide) intermacro-molecular complex has been successfully prepared through hydrogen bonding by mastication through a twin-roller. The experimental results show that the the complex can not be extracted by methanol and has a better thermal stability as compared with its constituent. The complex is an efficacious compati-bilizer for quite a few polymer blend systems. PMMA/PEO (67/33) after blending with a small amount of the complex [PMMA/PEO/P(MMA-MAA)/PEOcomplex), 63/30/7] is plasticized quite well, and its mechanical properties get improved. SEMand TEM observations reveal that the presence of P(MMA-MAA)/PEO complex will reduce the size of the domains and increase the homogeneity of the system.
    Hydroperoxidation of EP Copolymer and Its Olefine Monomer Grafting Reaction
    Chen Xue-xin, Lin Yi-ye, Lin Shang-an
    1991, 12(3):  417-420. 
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    Hydroperoxidation of ethylene-propylene copolymer with ozone contained in oxygen stream was investigated. The effects of temperature, concentration, radical-generating agent, additive, and reaction time on hydroperoxyl content were studied. The hydroperoxidation product (EPHP) was used to initiate olefine monomers, such as styrene, etc. for grafting copolymerization and examination of toughening effect of the grafted EPin the blend.
    Synthesis and Properties of a Chiral Chelating Resin Supported by Phenol-Formaldehyde Copolymer
    Ma Jian-biao, He Bing-lin
    1991, 12(3):  421-422. 
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    The microspheric phenol-formaldehyde copolymer, prepared by suspension polymerization from phenol and formaldehyde, was grafted by L-proline through 2-hydroxy propylene spacer to give a chiral chelating resin. Its copper(Ⅱ) chelate could be used as the stationary phase for the ligand-ex-change chromatography to resolve the racemates of proline, valine, isoleucine, methionine, histidine, asparagine,aspartic acid, and glutamic acid respectively.
    Studies on Immobilization of Papain
    Shui De-xin, Jiang Yong-ming, Zhao Guo-jun, Shi Wei, Shi Yong-chang, Yan Jin-wen, Jiang Jia-xian
    1991, 12(3):  423-425. 
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    This is a report of some results on papain immobilized on chitosan with glutaraldehyde. The effects of the proportion of papain to chitosan, the concentration of glutaraldehyde, temperature, pHvalue and other factors on immobilization of the enzyme were investigated. Characteristic of the immobilized papain was also studied. The results show that the optimum temperature for immobilizing pa-pain is 70℃ 5 the optimum pH is 8. 0; the half-life (t1/2) for the immobilized papain is 30 days; the activity recoverv for the immobilized oaoain is 47%.
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