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    24 April 1989, Volume 10 Issue 4
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    Articles
    Preparation, Properties and Determination of Standard Molar Enthalpies of Formation for Rare Earth Isothiocyanates Lower Hydrates
    Yin Jingzhi, Jiang Bengao, Sun Tongsan, Zhang Jianhua, Pan Jingzhi, Tang Xiaoming
    1989, 10(4):  329-334. 
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    The lower hydrates RE(NCS)3·mH2O(when RE=La, Ce, Pr, Nd, m=4.5; when RE=Sm, Eu, Gd, Dy, Ho, Yb, Y, m=3) were prepared by means of dehydration of corresponding higher hydrates RE(NCS)3·nH2O (when RE=La, Ce, Pr, Nd, n=7;when RE=Sm, Eu ..Gd, Dy, Ho, Yb, Y, n=6). The melting points of RE(NCS)3·mH2O and RE(NCS)3·nH2O were determined by means of capillary tubes.Both integral heats of solution of RE(NCS)3·mH2O and RE(NCS)3·nH2O (except Y) in water were measured calorimetically at 298.15K. The standard enthalpies of formation of ten lower hydrates RE(NCS)3·mH2O were obtained. The standard dehydration enthalpies △Hn→m°of higher hydrates RE(NCS)3·nH2O to corresponding lower hydrates RE(NCS)3·mH2O and lattice energies of RE(NCS)3·mH2O were also calculated. The corresponding data of RE(NCS)3· mH2O (RE=Tb, Er, Tm, Lu) were estimated.
    The Reaction of Superoxide Anion with Some Binuclear Copper(Ⅱ) Complexes of a 20-Membered Hexaaza Macrocyclic Ligand
    Luo Qinhui, Shen Mengchang, Peng Qingyun, Zhang Zheng
    1989, 10(4):  335-340. 
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    Six coordination compounds were synthesized by condensation reactions of 2,6-diacetylpyridine (DAP) with 1,3-diaminepropane in the presence of metal ions. Four of them have not been reported up to now. The structures of complexes were proved by the IRspectra and elemental analysis. We found that the spectra of complexes are similar to that of superoxide dismutase(SOD), and the SOD activity of complexes was measured by illumination method. The reaction mechanism of complexes with superoxide is studied by EPR. The results show that not only catalysis reaction but also oxidation one took place. The catalytic mechanism is also discussed.
    The Making Pore Affected by Template for ZSM-5 Molecular Sieves
    Wang Dingyi, He Jun, Yin Weizhen, Zheng Xiangmiao, Song Tianyou, Meng XianPing, Xiang Shouhe
    1989, 10(4):  341-344. 
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    The ZSM-5 type zeolite molecular sieves of different Si/Al ratios were synthesized with different templates. After driving out the templates at 560℃, the samples were saturated with adsorbed water, and then the crystal-linity and the volume of cell were determined by X-ray diffraction for poly-crystalline materials.It was discovered that the volumes of cell were linear with content of A12O3weight percent for a series of molecular sieves of the same template but the slope and intercept of lines were unlike for samples of unlike templates, that is,volume of cell or pore volume of the samples of unlike templates were unequal in case of same content of A12O3weight percent. Therefore, it may be deduced that templates play a support and location role in crystalline of molecular sieves for making pore.
    The Chelating Competition for Bovine Serum Albumin Bound Ni(Ⅱ)
    Li Rongchang, Gao Jingmin, Wu Hongyan, Wang Kui
    1989, 10(4):  345-350. 
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    The mobilizing powers of thirteen chelating agents for Bovine Albumin Bound Ni(Ⅱ) (BSANi(Ⅱ) were studied by gel chromatographic method. The experimental results show that the polyaminopolycarboxylate type chelators, especially DTPA and NTA are stronger mobilizing ligands than the mercapto chelators. The kinetics of these reactions have been studied at pH=7.4, and the mechanism has been elucidated. The reactions of His and EDTA with BSANi(Ⅱ) were found following the dissociation mechanism, but iminodiace-tic acid (IDA) and DTPA, association mechanism. The kinetic parameters were determined by dialysis method. The potentiality of the chelators as the agents to accelerate the excretion of Ni is discussed on the basis of the F.
    Correlation and Application of Three Major Parameters in the Differential Spectrophotometry with an Electrical Reference
    Gu Jingfei
    1989, 10(4):  351-355. 
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    This paper describes the definitions and properties of three parameters, reference of 100% transmittance Tr, the counter-microcurrent reference i and scale magnification x in the differential spectrophotometry with an electrical reference (ERDS), and deduces the expression formula of the reference of 0% transmittance TR, and points out the correlations of the parameters. The relative error function diagram of different x in ERDS has been drawn by a computer. By using this method, a good result has been obtained in determining P2O5in phosphate rock.
    Non-Equilibrium Potentiometric Titrations Using Kalman Filtering
    Wang Kemin, Li lie, Yu Ruqin
    1989, 10(4):  356-359. 
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    A new dodecyl sulfonate-selective PVC membrane electrode based on long-chain tetraalkyhin neutral carriers was prepared. By using this electrode as the indicator electrode, tetradecylpyridinium chloride can be titrated with dodecyl sulfonate potentiometrically in a fast, continuous, non-equilibrium way. The equivalence point of this non-equilibrium potentiometric titration system can be found chemometrically with the aid of Kalman filtering. The proposed procedure and Kalman filter algorithm effectively shortened the time of analysis in potentiometric titrations.
    Resin Phase Spectrophotometry(Ⅲ)--Rare Earth-Nitrate-Diazoderivatives of Chromotropic Acid Coloring Reaction on Resin Phase
    Yang Quansheng, Nie Jilan, Guo Qun, Tan Yuquan
    1989, 10(4):  360-363. 
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    Six common diazoderivatives of chromotropic acid as coloring reagents on resin phase were selected for determination of rare earth. The factors of affecting resin adsorption ratio arc preliminarily discussed. The experimental results showed that in the medium of nitric acid, trichloroarsenazo and trioromoarsenazo may be used to resin phase spectrophotometry of rare earth, when a large number of nitrate exist.
    Long-Chain Alkyl (2-Hydroxyethyl) Dimethylammonium Chlorides as Micellar Analytical Sensitizer
    Xie Hui, Yu Ruqiu
    1989, 10(4):  364-368. 
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    Three micellar modifying analytical reagents containing a quaternarynitrqgen atom and a hydroxyl group, i.e. hexadecyl (2-hydroxyethyl)-dimethylammonium chloride (HEMAC), tetradecyl (2-hydroxyethyl) dimethyl-ammanium chloride (TEMAC) and dodecyl (2-hydroxyethyl)dimethylammoniumchloride (DEMAC) were synthesized. The physico-chemical properties andanalytical characteristics of these reagents are evaluated. The synthesizedsurfactants can be used as sensitizing and solubilizing reagents for spectrophoto-metric analysis. Some examples of the micellar improved spectropl otometricsystems by using these reagents such as Sc(Ⅲ)-CAS, Fe(Ⅲ)-CASand Ge(Ⅳ)-PF are given. The sensitizing effects of the proposed reagents are similar tothose of cationic surfactants mixed with alcoholic organic solvents.
    Studies on the Synthesis and Antitumour Activity of γ-(Arylideneamino)propylsilatranes
    Ding Qizhu, Luo Xuangan, Zhuo Renxi
    1989, 10(4):  369-372. 
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    Fourteen γ-(arylideneamino)propylsilatranes were synthesized by the condensation of arylaldehydes with γ-aminopropylsilatrane in benzene. The structure of these new compounds were identified by 1HNMR, IR and UV as well as elemental analysis. Animal screening data show that the inhibition ratios of γ-(3-nitrobenzylideneamino)propylsilatrane, γ-(2-hydroxybenzylideneamino)pro-pylsilatrane, and γ-(2,4-dihydroxybenzylideneamino)propylsilatrane against Erlich ascites cancer in mice are 41.6%, 51.1% and 53.1%, respectively.
    A New Method to Synthesize a-Aryl-p-Nitroethylphosphonates
    Li Yugui, Wang Guohong, Zhang Diankun, Liu Tingyang, Miao Fangming, Liu Xiaolan, Cao Jinhong, Guo Hangzhou
    1989, 10(4):  373-378. 
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    This paper reports a one-pot reaction of the Arbuzov-Michael addition of acidic phosphites to α-aryl-β-nitroalkenes. The reaction was carried out smoothly with an excess of trimethylchlorosilane and acid-binding agents, giving high yields of addition products Ia-n. The structures of these compounds were characterized by elemental analysis, IR, 1HNMR and MS. It was found that in these molecules the O,O-dialkyl groups on the phosphorus atom were unequivalent. This fact was also confirmed by the X-ray structure determination of one representative compound, Ij.
    The Synthesis and Property of a Novel Type of Composite ZSM-5 Zeolite/Asbestos Material
    Wu Chuanchang, Gu Liangzheng, Yue Ying, Qin Guanlin
    1989, 10(4):  379-382. 
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    A novel type of composite ZSM-5 zeolite/asbestos material(Z-5-A), whose ZSM-5 zeolite was embedded in the crystalline asbestos fibers as a substrate, was synthesized hydrothermally at 160℃. The reactants were asbestos as a part of silicon reesource, water glass, aluminium sulphate, amine and water. Z-5-Awas charactrized using the methods of XRD, SEM and adsorption and its composition was analysed. The results showed that H-type composite ZSM-5 zeolite/asbestos material(H-Z-5-A) was different from H-ZSM-5 zeolite and there were both acid and base sites on the surface.The H-Z-5-A can be used as a catalyst, on which the selectivity of light alkene in the methanol conversion was superior to that on H-ZSM-5 catalyst. On ZnCr/H-Z-5-Acatalyst,which was a mixture of H-Z-5-Awith Zn-Cr catalyst, the coke deposits, conversion of CO and HC selectivity of the gasoline synthesized from water gas by one-step method were also superior to those -on the Zn-Cr/HZSM-5 catalyst.
    Relationiship Between the Acid-Base Properties of Zeolite Surface and the Activity of Side-Chain Alkylation of Toluene with Methanol
    Wu Chuanchang, Hou Dongming, Gu Liangzheng, Qin Guaulin
    1989, 10(4):  383-386. 
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    The relations of the acid-base properties of X-type Zeolite to the side-chain alkylation of toluene with methanol have been studied by TPD, IR, TPSR and other methods. The alkylation mechanism has also been discussed. The results showed that methanol initially decomposed into HCHO on the strong base sites of zeolite, subsequently, HCHO reacted with toluene, which was on the acid sites, and produced styrene. The catalytic activity of the alkylation is mainly dependent on the number of the strong base sites on the zeolite but the excess of strong base sites may lead to the further decomposition of HCHO into CO which is unfavourable to the formation of styrene.The number and strength of acid-base on zeolite can be adjusted by alkali-cation exchange and by impregnation in H3BO3and KOH. Therefore it affected on the catalytic activity.Asatisfactory yield of styrene is obtained on a KX(H3BO3/KOH) zeolite sample which was impregnated with the mixed solution of H3BO3and KOH (molar ratio=1:1), and the high activity is attributed to the proper number of strong base sites in the zeolite sample.
    The Stability of Cyclic Polymeric Conjugated Hydrocarbons with Cyclic Conjugated Hydrocarbons as a Repeating Unit
    Li Qianshu, Zhang Xingchen, Li Zhiru
    1989, 10(4):  387-391. 
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    In this paper, the stability of cyclic polymeric conjugated hydrocarbons with cyclic conjugated hydrocarbons as a repeating unit was discussed by means of CNDO/2 quantum chemical calculation, and it is found that the molecule -(C4H2)-4is the most possible potential synthetic objective.
    Studies on RuO2Electrode by XPS and UPS
    Cui Chengqiang, Yao Shibing, Zhou Shaomin
    1989, 10(4):  392-395. 
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    The surface compositions and valence band structures of RuO2electrodes prepared at different sintering temperatures have been studied by means of XPS and UPS. It was shown that O/Ru atomic ratio, I (σ + π)/I(π*) intensity ratio and the π* binding energy increase with the increasing of the sintering temperature, indicating the decreasing of the density of d-electron beneath Fermi level and the difficulty of RuO2to be oxidized to activation intermediate RuO4.On the basis of the facts above we suggested that the active sites of RuO2etectrode for oxygen evolution are oxygen-deficiency rather than RuO3· The fact that the electrocatalytical activation of RuO2electrode decreases as the sinterering temperature increasing was also explained.
    An Investigation of Electronic Structure of Molecular Fragment Models of a Binuclear Ferrous Complex Fe2(C13H9NO2)2·2H2O
    Cai Zhengting, Guan Daren, Wang Zexin, Liu Dexin, Zhang Ruiqin
    1989, 10(4):  396-400. 
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    Using the CNDO/2 method, the electronic structure of molecular fragment models for a binuclear ferrous complex Fe2(C13H9NO2)2·2H2O has been calculated. The interaction between its planar structure unit and crystal water has been also studied. It is entirely possible that there are three different orientations of water molecule from the results of geometry optimization. The "umbrella" orientation of water is the most stable one of those we have researched. The interaction has resulted in the energy level shifts and the new structure below fermi energy Ef. By comparing with the local density of states (LDOS) of related atoms it is shown that such interaction, which is mainly localized between water molecule and oxygen atoms in the planar structure unit, has the nearest neighbour character. These calculated results have been compared with some experimental ones reasonably.
    Isolation and Preliminary Characterization of Properties of Middle Molecules from Sera of Uremic Patients
    Yuan Zhi, Zhang Ji, Zhao Fenzhi, Mi Huaifeng, He Binglin
    1989, 10(4):  401-405. 
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    Middle molecules in sera of uremic patients (UMM) were isolated on Sephadex G-15 gel-filtration Chromatography eluted with triethylamine caibonate buffer. Dry sample of middle molecules could be obtained with lyophilization. From the dialysis fluids of the uremic patients treated with continuous ambulatory peritoneal dialysis (CAPD) the same UMM fractions could be obtained. The behaviours of gel-filtration chromatography, UVand JRabsorptions of UMM from the sera and the dialysis fluids of uremic patients were identical. In 206nm and 235 nm, there were 2 UVabsorption peaks and in 3246, 1516, 1122 and 613 cm-1there were 4 characteristic IR-absorption peaks which are not found in normal sera. The Compositions responsible for the behaviours of UV and IR absorptions are found in the third sub-peak after the middle molecules were further separated by ion-exchange chromatography. The contents of peptides and free amino acid from the sample of UMM were quantitatively analyzed. They are between one to three percent.
    The Investigation of Network Structure of Aai-BbjType Polycondensate( Ⅰ)--The Sol-Gel Distribution Theory
    Zheng Fuan, Hu Yuxin, Min Yonggang, Tang Xinyi
    1989, 10(4):  406-409. 
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    This paper reports the effect of intramolecular cyclization reaction and proposes a new theoretical model and method, evaluates the modified sol-gel distribution theory including all parameters of reaction. Using polyesters as a model compound to test the theory, we found the theoretical values agreed with the c perimental ones.
    Improvement of the Method for Semi-Synthesis of the Human Insulin
    Zhou Hui, Cha Xiao, Zheng Xiaofei, Li Wei, Shen Jiacong
    1989, 10(4):  410-411. 
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    Trypsin was used in catalysing the coupling between desalanine-B30-insulin(DAI) and Thr(Bu)OBu, DAI was obtained by digestion of porcine insulin with carboxypeptidase A. Thr(Bu)OBu was directly synthesized without N-terminal protection, different from general way and a high yield of human insulin was obtained. The purity of the semi-synthetic human insulin was one band of electrophoresis. It can be easily crystallized. The amino acid analysis of the semi-synthetic human insulin was identical with the theoretical value. The radiation inactivation test shows the semi-synthetic human insulin has the same insulin-binding activity with the porcine insulin.
    The Study of Synergistic Extractive System of RE(Ⅲ) Ions with HPMBP-TPhPO
    Wang Zhitang, Li Shengchong
    1989, 10(4):  412-414. 
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    The mechanism of the synergistic extraction of 15 trivalent rare earth ions with HPMBP and TPhPO was investigated by the two-phase titration method. The compositions and the stability constants of synergistic complexes were determined at temperature of 15℃, 25℃, 35℃.
    Investigation on Differential Pulse Polarography(Ⅹ)--Theory of Polarographic Currents Controlled by Diffusion and a Followed Chemical Reaction
    Zhang Jianrong, Zhang Zuxun
    1989, 10(4):  415-417. 
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    The equation of the pulse polarographic curve controlled by diffusion and a followed chemical reaction is derived in this paper.Tests were carried out to verify the theory by using the oxidation of cadmium amalgam in KNO3, HOAc-NaOAc, EDTA (or NTA) solution. The results obtained are in good agreement with the theoretical conclusion.The K,k1k2values determined agree with those obtained by other polarographic methods found in literatures.
    The Study of Determination of Cr(Ⅲ), Cr(Ⅵ) by Absorption Spectroelectrochemistry
    Huang Ganquan, Luo Huanguang, Fang Guobin, Zhang Wuping
    1989, 10(4):  418-420. 
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    The measurement conditions of absorption spectroelectrochemistry of Cr(Ⅲ) were investigated. The determination method of Cr(Ⅲ) and Cr(Ⅵ) in electroplating solution was proposed. The results show that the best sensitivity was obtained when atomic absorption spectrophotometer and hollow cathode light source were in place of the UVspectrophotometer and deuterium lamp was used for measurement absorption spectroelectrochemistry of Cr(Ⅲ). The technique yields increase 1.7 times in sensitivity compared with west method.
    Improvement for the Synthesis of Cholest-⊿4-3,6-dione
    Li Tongshuang, Li Yulin, Tan Zhen, Liang Xiaotian
    1989, 10(4):  421-422. 
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    Cholest-⊿4-3,6-dione was synthesized by oxidizing cholesterol with PDC.
    Studies on Condensation Reaction of Methyldiphlorosilane
    Qiu Huayu, Du Zuodong
    1989, 10(4):  423-425. 
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    The condensation reaction of methyldichlorosilane in mixed solvents with different proportion of toluene and dioxane via various coupling reagents (Na,K,Li or Na/Kalloy) were studied in detail. The effect of reaction temperature and time was also suggested. The structure of polysilane obtained from coupling of MeHSiCl2by Na/Kalloy in THF may be chain-cyclic form.
    Studies on the Synthesis of Amino Acids(Ⅲ) --Phase-Transfer Catalytic Alkylations of N-Ethoxycarbonylmethyl Imidates
    Shi Yaozeng, Shi Nongyuan, Sun Xiangzhen, Hu Hongwen
    1989, 10(4):  426-428. 
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    Ethyl N-(ethoxycarbonylmethyl)benzenecarboximidate 1a and ethyl N-(ethoxycarbonylmethyl)ethanimidate 1b were alkylated under the solid-liquid PTCconditions by using solid K2CO3or KOH as a base and n-Bu4N+Br-as a phasetransfer catalyst. Subsequent hydrolysis furnished the corresponding a-amino acids.
    Thermogravimetric Determination for the Components of Nonstoichiometric Compounds NaxWO3
    Wang Bengen, Pan Yi
    1989, 10(4):  429-430. 
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    The value of x in sodium tungsten bronzes NaxWO3, a nonstoichio-metric compound, is variable falling in the range 0<x<1. It can be determined by atomic-absorption spectrometry or ion-selective electrodes.The methods have certain disadvantages because the NaxWO3is chemically inert. The present report relates to a new method for researching components of NaxWO, by thermogravimetry.
    The Extraction Kinetics of Cobalt (Ⅱ) Thiocyanate with Primary Amine N1923 by Growing Drop Method
    Sun Sixiu, Gao Zili, Gai Huifa, Liu Yuanjun, Shen Jinglan
    1989, 10(4):  431-433. 
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    The forward initial rate of the extraction of cobalt(Ⅱ) thiocyanate with primary amine N1923 was measured by means of the growing drop method at 25 ± 1℃.The effect of the temperature on the extraction rate was also investigated. The experimental results show that the rate-determining step of the .extraction process may be the following interfacial reactions:The activation energy of the process was calculated to be 15.1 kJ·mol-1.
    Luminescence Kinetics of Eu3+Complexes with Time-Resolved Spectrum
    Zhao Xiaoping, Fei Haosheng, Tian Ke, Li Tiejin
    1989, 10(4):  434-436. 
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    The kinetics of luminescence and energy transfer in Eu(TTA) and Eu(DB)3in organic solutions with time-resolved spectrum is reported. Theresults show that the energy absorbed by the organic ligands transfers to the 5D1level of Eu3+, then the 5D0level and is populated by nonradiativeenergy transfer from the 5D1level.
    Characterization of Transition Phenomena in Polystyrene -sulfonic Acid by Inverse Gas Chromatography
    Ye Wenwen, Dai Qingping, Xu Feng, Gu Qingchao
    1989, 10(4):  437-439. 
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    The transition phenomena of polyslyrenesulfonic acid (PSSA) with various degree of sulfonation were investigated by inverse gas chromatograpl y (IGC). The model Z-shaped retention diagrams have been obtained. The glass transition temperatures of a series of PSSA which were measured from these diagrams are in agreement with those measured by thermally stimulated discharge current analysis, differential scanning calorimetry and dynamic viscoelastometry previously. Furthermore, the IGC method with excellence of convenience and accuracy might provide more definite data for explaining the molecular mechanism of transition phenomena of solid PSSAionomers. In addition, we have explored the effect of the water adsorption of PSSA on determination of Tg, According to these Z-shaped retention diagrams, the enthalpy of adsorption of n-dodecane on surface of PSSA was also calculated. The result of this calculation shows the enthalpy of adsorption was essentially independent of the degree of sulfonation of PSSA.
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