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Table of Content

    24 February 1989, Volume 10 Issue 2
    Articles
    The Kinetic Study for the Transformation Reaction from Paratungstate A to Paratungstate B
    Jiang Anren, Gong Keyin, Pang Zhen
    1989, 10(2):  113-117. 
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    The rate constants of Para Bformation reaction have been determined within Zvalues between 0.35 and 1.10 by means of the H2O2-SO2method at 80℃. The reaction has been confirmed a transformation process from Para Ato Para B. The rate constants are inversely proportional to the Zvalues and directly proportional to the contact area of the glass vessel per unit volume of the solution. The reaction has the characteristic of zero-order with the activation energy of 70.72kJ/mol in glass vessel. The rate is negligible in the plastic vessel. According to the characteristics of the transformation reaction, the chemical adsorption-condensation mechanism has been suggested.
    Studies on Rare Earth Complexes of Aminoacids(Ⅰ) --Synthesis and Crystal Structure of TrigJycinato-Diaquo- Praseodymium Chlorides
    Jin Tianzhu, Yang Changqing, Yang Qingchuan, Wu lingnang, Xu Guangxian
    1989, 10(2):  118-122. 
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    The triglycinato-diaquo-lanthanide chlorides [Ln(Gly)3(H2O)2]·Cl3·H2O have been synthesized in the aqueous solution (Ln=Pr, Nd),The crystal structure of this complex compound has been determined by X-ray analysis as follws:Space group P212121; a=4.779(1), b=12.052(3), c=30.953(11)Å; Z=4. The crystal is a one-dimentional chain complex of infinite length with three glycinic acid, NH3+CH2COO-, serving as bridging groups connecting neighboring Pr atoms (See Fig. 2).In addrtion, there are two H2O molecules coordinated to each Pr atom, so that the coordination number of Pr is nine, forming a distorted tricapped trigon-alprism. There is another H3O molecule not coordinated to Pr. The three Cl-anions are in the neighbourhood of -NH3+ cations. There is no direct metal-metal bond between Pr atoms.
    Interconversion Between Hexa- and Decatungstic Acids in Solutions
    Zhu Sisan, Gu Yidong(Yih-Tong Ku)
    1989, 10(2):  123-128. 
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    The interconversion between hexa- and decatungstic acids in solutions has been studied through UVabsorption spectra data.. In aq. solution at pH 1-4, H2W6O19changes rapidly to H4W10O32The rate constant k is 5.3 × 10-3s-1, t1/2being 1.31s, at pH 3.57 and 25℃. Hydrogen ion retards the conversion from W6O192- to W10O324-.On the contrary, H4W10O32in organic media slowly transforms into H2W6O19at ordinary temparature. Its complete conversion will need about 30 days at 25℃. When temparature rises to 78℃, however, it will only require half an hour. Water inhibits the change from W10O52to W6O192-seriously.The interconversion between them can therefore be taken as.
    Synthesis, Characterization and Crystal Structure of Di-(1-Phenyl-3-Methyl-4-Trifluoroacetylpyrazolone-5) Di-(Ethanol) Cobalt (Ⅱ)
    Huang Chunhui, Wang Kezhi, Xu Zheahua, Xu Guangxian, Han Yuzhen, Shi Nicheng
    1989, 10(2):  129-134. 
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    Awine red mixed ligand complex of 1-phenyl-3-methyl-4-trifluoro-acetyl pyrazolone-5(HPMTFP)and ethyl alcohol with cobalt having molecular formula Co(PMTFP)2·2C2H5OH has been synthesized and studied by solubility, conductometric method, magnectometry, IR, far-IR, thermo analysis(TG-DTA) as well as single crystal X-ray diffractometry. Its crystal and molecular structure has been determined by a single crystal X-ray diffractometer. 4576 independent reflections were collected, of which 2698 observable reflections (I≥2σ(IO)) were used for structure refinement. The final deviation factor R=Rw=0.094. The complex crystallizes in triclinic with space group P1. The unit cell parameters are as follows:a=10.301(4)Å.b=12.038(7)Å,c=13.806 (5)Å;α=88. 370(48), β=69.616 (27), γ=81.700(46); V=1587.6( 1.31)Å3, Z=2, dcalc= 1.44 g/cm5, dexp=1.46g/cm3.
    A General Computer Program for the Study of Mechanism of Chelate Extraction with the Method of Two-Phase pH Titrations
    Zhang Kaicheng, Cai Qingyun
    1989, 10(2):  135-139. 
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    A general computer program, SCTPT, written in FORTRAN IV, is described which uses Marquardt-Fletcher modification of Gauss-Newton method to calculate the stability constants of the type MiAiHkin two-phase solution from the pHtitrations. The minimization is perfomed with respect to the square of the titre and the analytical derivatives are employed. This program possesses high speed and good convergence.The close initial estimates are not required and can be varied in a range of 4-15 orders of magnitude. This program has been tested on the Cu-PMBP and Zn-PMBPextraction systems and found to be very convenient for use and gives satisfactory results.
    Studies of the Color System of Zn(Ⅱ)-TPPS4-CTAB and the Determination of Trace Zinc with Triwave-length Spectrophotometry
    Pan Zuting, Xu Mianyi, Liu Xiaoxiu
    1989, 10(2):  140-143. 
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    Zinc(Ⅱ) reacts quickly with tetrakis- (4-sulphophenyl) porphyrin (TPPS4) and cethyltrimethylammonium bromide (CTAB) in the presence of mercury(Ⅱ) at room temperature. The complexes Zn(n)-TPPS4-CTAB, Hg(Ⅱ)-TPPS4-GTAB and the reagent show maximum absorption wavelengths at 427 nm, 447 nm and 417 nm, respectively. Anew method for the determination of trace zinc with triwavelength spectrophotometry is described and the molar absorptivity is 8.5 ×105L·mol-1cm-1. After the ion-exchange separation, this method is of high selectivity and has been successfully applied to the determination of zinc in aluminium alloys, ores, natural water and human hair.
    Studies on 1,4-Bis(2-Phenyl-1,3,4-Oxadiazol-5-yl) Benzene and Its Derivatives (Ⅲ) --Influence of Some Inorganic Ions on the Fluorescence Strength
    Pan Jiaxing, Chen Jingshan, Gao Zhenheng
    1989, 10(2):  144-147. 
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    The hyperchromic phenomena of B(Ⅲ), Al(Ⅲ), Ga(Ⅲ) on the fluorescence spectra of PDPDP were observed. The quenching effects of Fe(Ⅲ), Co (Ⅱ), Ni(Ⅱ) on the fluorescence spectra of PDPDPwere discussed.
    A New Method for the Synthesis of Diaza and Triaza Crown Ethers
    Wang Defen, Jiang Lijian, Gong Yan, Hu Hongwen
    1989, 10(2):  148-152. 
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    In this paper a new method for the synthesis of di- and tri-aza crown ethers starting from saccharin is reported. Saccharin is first alkylated with di-or tri-ethylene glycol dichloride and N,N-(β-chloroethyl) butyl amine in DMF solution in the presence of small amount of potassium iodide. The N-alkylated saccharin is treated with ammonia and transformed into the N-alkylated o-carbamoyl benzene sulfonamide, which is then alkylated once again with ditosylates of di- and tri-ethylene glycol to form the crown ethers on the imino groups protected with o-carbamoyl benzene sulfonyl group. Di- and triaza crown ethers are obtained by removing the protective group on the nitrogen with 20% hydrochloric acid. By this method, are prepared 10 new intermediates, which can be used to synthesize di- and tri-aza crown ethers bridged by like or different chains. The total yield of 1,10-diaza-18-crown-6 amounts to 36% close to that by the high dilution method starting from 1, 8-diaza-3,7-dioxaoctane. Compared with the methods reported in the literature, the features of the new method are. (1) using cheap starting materials (2) the o-carbamoyl benzene sulfonyl protective groups can be removed more easily than tosyl group.
    Study on Indirect Photometric High-performance Liquid Chromatography of Aliphatic Alcohols and Acidswith Acridine as Detection Reagent
    Da Shilu, Zhao Wenkuan, Qiu Yaoling, Feng Qi
    1989, 10(2):  153-157. 
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    By using acridine as the detection reagent, the indirect photometric high-performance liquid chromatography of aliphatic alcohols and acids is investigated. The factors that affect retention and sensitivity of detection are discussed. The differences of retention behavior and detection response between alcohols and acids are interpreted by the chromatographic mechanisms. New chromatographic system monitored by indirect photometry for practical separations and detections of alcohols and acids are presented.
    Addition Reaction of Aryloxyphenylthiophosphonyl Hydrazides with Iso(thio)cyanates
    Jin Guiyu, Sha Yuewu, Cai Jianping, Chen Ruyu, Miao Fangming, Liu Xiaolan
    1989, 10(2):  158-163. 
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    Some new N-thionophosphonyl- and N,N'-bis(thionophosphonyl) thio-semicarbazides were synthesized.The diastereoisomers of N,N'-(thionophosphonyl) thiosemicarbazides possessing two chiral P-atoms were separated and their structures were determined by IR, 1HNMR, MS spectra, elemental analysis and X-ray diffraction method. The MS spectra of mono- and disubstituted thiophosphonyla-minourea were discussed.
    Studies on Ammo Acid Derivatives of Organosilicon Compounds
    Bei Xiaolai, Qiu Huayu, Luo Danming, Wen Xiaoyao, Du Zuodong
    1989, 10(2):  164-167. 
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    Aseries of new amino acid derivatives of organosilicon compounds have been synthesized by hydro silylation of ethyl ester of N-allyl amino acids with organosilicon compounds containing Si-Hgroup. Anew method was suggested for the syntheses of compounds n and n. The structures of the new compounds Ⅲ-Ⅶ have been determined by elemental analysis, 1HNMR and JR.
    Selectivity and Crystal Phase of V-P-O Catalyst for Selective Oxidation of n-Butane
    Lin Peiyan, Li Heyi, Shi Wenjun, Zheng Hanxing, Peng Jian, Shan Shaochun
    1989, 10(2):  168-172. 
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    A series of V-P-Ocatalysts in the range of P/V ratio=0.9, 1.0, 1.1, with different calcination temperature and calcination atmosphere for n-butane oxidation to maleic anhydride were prepared by the method of benzyl alcohol reduction. Crystal phases of the catalysts were determined by XRD and FT-IR. The average valence of vanadium in the catalysts was determined by chemical titration. It was considered that the main factor which was related to seclectivity is the formation of crystalline catalysts, the mixed crystal of (VO)2P2O7and a part of a-VOPO4in good crystallinity is active phase in the redox dynamic process. The reaction is the reaction of structure sensitivity.
    XPS Studies of Tetraphenyl-2-Nitro-porphyrin Metal Complexes
    Wei Quan, Guan Yousheng, Cao Xizhang
    1989, 10(2):  173-175. 
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    The metal Complexes coordinated with tetrapbenyl porphyrin and tetraphenyl-2-nitroporphyrin were investigated by XPS. These metal complexes in which ions were mosaiced into big π system of conjugated ring structrue were demonstrated by π→π* transition energy, transition probability and N1tshift of binding energy. Furthermore, it was proved that -NO3group is in conjunction with a pyrrole ring and this leads to an increase of Lewis acidity.
    The Quantum Chemistry Calculations for the Structural Rule of Boranes
    Li Qianshu, Tang AuQin
    1989, 10(2):  176-181. 
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    By means of EHMO method we have calculated in this paper various polyhedral skeletons Bn with n=3~12, closo-, nido-, arachno-, monocapped-and bicappad-, to verify the structural rule of polyheral boranes, the number of valence bonding molecular orbitals BMO=4n-[f+3(s+1)]where n, f and s are topologocal parameters of skeleton Bn. Then we have discussed the relationship between the geometry and the number of valence bonding orbitals of a skeleton Bn.
    Investigation of Preparation of Copolymer of Triallyl Cyanurate DVB and Methyl Acrylate and Their Pore Structure
    He Binglin, Zhang Gengyi, Guo Xianquan, Zhao Fenzhi, Yang Zhixin
    1989, 10(2):  182-185. 
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    A series of copolymers were prepared by methyl acrylate and triallyl cyanurate and divinylbenzene. The effects of properties and amounts of mixed cross linking agent and diluents on physical properties, such as specific surface area, pore volume, average pore diameter, pore size distribution and porosity were investigated and disscused. The affect of the lower activities of triallyl cyanurate in a mixed cross linking agent copolymerization were disscused.
    Investigation of Crystallization of PPS by Employing Synchrotron Radiation
    Lin Dehou, P. B?secke, H. G. Zachmann
    1989, 10(2):  186-189. 
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    This papar is about the investigation of the isothermal crystallization process by means of the X-ray scattering of synchrotron radiation. Through experiments, we determined the curve of small and wide angles scattering intensity and maximum of scattering peak moved to smaller angle as the crystallization temperature goes high. From the resolution charts which were gained different Tctemperature from the determination of PPS SAXs and WAXS, one can calculate the smallest value of PPS crystallization speed (t1/2) which is 0.47 min and corresponds to Tctemperature 189℃. The crystallization speed is rather slow at temperature below 100℃ and above 250℃. Long Period increases as the temperature goes high and goes down. When the temperature goes near to 250℃, the result of determining density tells us the density can increase greatly. From the break-point on the Q-Tcurve in the range of 30-225℃ one can find out Tgtemperature of PPSis 89 ± 5℃ (heating speed is 10℃/min). According to formula (3) at Tgtemperature, the difference of the thermal expansion coefficient of PPSbetween crystals and amorphous regions is delta alpha, Δa'=(aa' -ac')=(0.76+0.03)×10-2-1.
    Effect of Lipophilic Salts on the Performance of Neutral Carrier-Based Calcium Selective Microelectrodes
    Qi Deyao, Hu Zhongmin
    1989, 10(2):  190-193. 
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    Several representative tetraphenylborate salts containing large organic cations were prepared, and the effect of them on the performance of calcium ion-selective microelectrodes based on neutral carrier (ETHlOOl) was systematically studied. The effect of the content of membrane components on the performance of the microelectrode made with sensor containing tetrabutylammonium tetraphenylborate was also evaluated with Latin square method. The optimum membrane composition was obtained.
    Studies on Electrochemical Analysis of Precious Metals (Ⅸ)--Determination of Micro-Rhodium by ASV
    Zhang Yuxiang, Lu Fan, Duan Guiyun, Yang Wenxiu
    1989, 10(2):  194-196. 
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    We used the cation exchange resin as enrichment to separate rhodium which has been successfully determined in the samples. Anew and simple system of determinating Rh at a glass carbon electrode by anodic stripping voltammetry (ASV) was studied. The optimum supporting electrolytic system was 0.07mol·dm-3H2SO4-HgCl2.Between quantitative orders of Rh3+from 10-10g/m Lto 10-7g/mL, the concentration on peak current is linear. The detection limit reached 0.1ng. The coefficient variation are 0.0057% and 0.0058% respectively with samples of chloridized residue and refined mineral for 6 replicate determinations. Results obtained by this method quite agree with that of other methods. The industrial waste water and second nickel anode mud were also determined. Its coefficient variations were 0.0087% and 0.010% respectively.The recovery rate of chloridized residue was in the range of 93-106%.
    Studies of the Effect of Mixed Solubilizers on the Coloured Ion-association Complex Systems
    Qi Wenbin, Luo Hongshan
    1989, 10(2):  197-199. 
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    The effects of macromolecular compounds (polyvinyl alcohol (PVA), arabic gum)-Triton X-100 mixture on the coloured ion-associated complex systems are investigated. It is found that these mixtures have good solubilization actions on many coloured ion-association complexes. The mechanism of the effect may be the synergism of PVA(arabic gum) and TritonX-100 which changes the microenvironment of the colour system. It creates a steric environment that is both benificial to the formation of ion-association complex and the accumulation of more colour reagent molecules. The formation of the complicated ion-association complex carried non-stoichiometric additional reagent molecules results in an increase of sensitivity.
    Spectrophotometric Determination of Trace Cobalt by Catalytic Decolorization
    Chen Guoshu, Yan Xiyuan. Nie Xiaodi
    1989, 10(2):  200-202. 
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    Go(Ⅱ) in ammonium hydroxide can accelerate the decolorizing indicative reaction of diphenylcarbazone being oxidized by air. Anew high-selective method for determining trace Co(Ⅱ) is described. The sensitivity of the method is 2×10-12g/mL, In the range of Cobalt 0-0.11μg/25.7mL the method was used to determine trace Co(Ⅱ) in Chinese medicinal herb with satisfactory results.
    Study on Thermolysis Process of Samarium Nitrate Hydrates
    Gao Shengli, Yang Zupei, Tan Qinde, Liu Yilun
    1989, 10(2):  203-205. 
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    The thermal decomposition of Sm(NO3)3·nH2O(n=6,5,4) has been studied with TG-DTG. The reactants, intermediates and end-products have also been characterized by IR.In addition,the apparent activation energies of dehydration were calculated with Kissinger method by means of TG-DTG curves at various step-up temperature rates and the enthalpies of dehydration were found by DSC.
    Synthesis and Crystal Structure of (Z)-1,2,5-Trimethyl-3-Pyrrolylmethylidene (Isop ropy lidene)-Succinic Anh ydride
    Wang Fan, Liu Zuocai, Wang Huanzhong, liang Qian
    1989, 10(2):  206-208. 
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    The title compound has been synthesized and the crystal structure has been determined by single-crystal X-ray diffraction techniques. Mt=259, triclinic crystal, space group P1 with a=8.116(1)Å,6=8.903(2)Å, c=9.995(2)Å, a=86.96(1)°, β=74.27(1)°, V=74.35(1)°, V=669.1(2)Å3and Z=2. The structure was solved by direct methods and Fourier Synthesis and refined by block-matrix least square method. The final result gives R=0.060 for 1196 independent reflections with |F|/σ(|F|)≥2.5. The compound is a (Z)-coplane molecule.
    Study of Metalloporphyrin Complexes and Their NO Surface Adspecies with FT-IR/PAS
    Zhou Muyi, Cao Shoujing, Ye Surong, Cheng Dadian
    1989, 10(2):  209-211. 
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    Fourier Transform Infrared Photoacoustic Spectroscopy (FT-IR/PAS) was applied to studying the metalloporphyrin(MTPP, M=Fe, Co, Ni, Cu and Mn) comlexes and their NO-surface adspecies. The changes of their spectra were observed and the peaks of adsorption with NOwere also found. The results showed that CoTPP and FeTPP have stronger abilities of coordination than others and the PAS characteristic bands of NO-surface species are at 1698.6cm-1for CoTPP-NO(a) and 1883.8cm-1for FeTPP-NO(a), respectively.
    The Calculation and Oomparision of the Main Chain of Insulin Molecules by CNDO/2 Method
    Shao Jun, Wu Ji'an, Wen Yuankai, Li Zhenmin
    1989, 10(2):  212-213. 
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    Considering the importance of the secondary structure of protein, we altered the scheme of the calculation scheme of the main chain of insulin molecules by CNDO/2 method. Using the scheme of the non-peptide cutting we proposed, we calculated and compared the atomic charge distribution of the monomeric molecule Ⅰ and monomeric molecule Ⅱ in insulin's crystal. The results we obtained reflect the efforts of secondary structure of insulin molecule on its main chain's charge distribution.
    Studies on Methanol Synthesis from CO2+H2over Supported Rhenium Catalysts
    Li Kai, Xu Zheng, Qian Zaihu
    1989, 10(2):  214-217. 
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    Methanol formation in the reactions of CO2+H2in a flow reactor under 5 atmospheric pressure over Re catalysts supported on a series of oxides (SiO2, TiO2, Nb2O5, γ-Al2O3, La2O3, CeO2, ZrO2) was studied. Among the catalysts used, Re/ZrO2, Re/CeO2and Re/La2O3showed an excellent activity and selectivity toward methanol at a mild reaction condition. XPS and FT-IR were used to characterize Re/X(X=ZrO2, CeO2γ-Al2O2) and study the absorbed states of CO2/H2over Re/ZrO2and Re/CeO2The Mechanism of methanol formation over Re/ZrO2and Re/CeO2was discussed.
    Studies on Thermotropic Liquid Crystalline Copolyesters--Terephthalates of Bisphenols as Rigid Spacers
    Zhang Hongzhi, Guan Zhibin
    1989, 10(2):  218-220. 
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    Two series of copolyesters based on p-acetoxybenzoic acid (Ac-HBA), terephthalic acid(TA) and bisphenol Adiacetate(Ac-BPA) or bisphenol Sdiacetate (Ac-BPS) were prepared by melt polycondensation technique. The copolyesters in a certain extent of compositions were thermotropic with wide liquid crystalline temperature ranges. The minimum amount of mesogenic units derived from Ac-HBAin feed necessary for the appearance of mesomorphic phase is about 10 % mol. Tgs of BPA series copolyesters were essentially constant and close to that of polymer of rigid spacer regardless of compositions. But the Tfs showed a minmum value towards the compositions.
    Studies on the Fluorescent Substance in Gastric Juice from Patients Suffering from Stomach Carcinoma
    Tian Ke, Wang Jindui, Dai Jin, Zhang Lifang, Ma Rongjiu, Chen Xiaoguang, Ding Zhonglian, Li Tiejin, Liu Zhiguang, Zheng Fumin
    1989, 10(2):  221-223. 
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    This paper reports a characteristic fluorescent substance in gastric juice from the patients suffering from stomach carcinoma and its probable existance form. The systematic separation for the gastric juice with stomach carcinoma was carried out by biochemical methods. The comparisons of the fluorescence spectra and excited spectra of the gastric juice with stomach carcinoma with that of the aqueous solution of riboflavin and the experiments based on the properties of riboflavins make us come to the conclusion that the characteristic fluorescent substance in the gastric juice from the patients of stomach carcinoma is riboflavin-binding protein and probably exists in phospholipid membrane.