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    24 December 1988, Volume 9 Issue 12
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    Articles
    Inhibition of Crystal Formation and Aggregation of Calcium Bilirubinate with Disodium 1-Hydroxyethanediphosphonate(EHDP)
    Wang Kui, Xu Shanjin, Hu Jiaping, Cheng Tianrong, Jin Fan
    1988, 9(12):  1207-1210. 
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    Disodium 1-hydroxyethanediphosphoriate was studied as an inhibitor of the formation and aggregation of calcium bilirubinate, the main component of pigment gallstone.The kinetics of calcium bilirubinate formation was studied at pH 7.9, 37+1℃, under nitrogen atmosphere, in the darkness. EHDPwas added in different levels, with or without choric acid. It is obvious that EHDPis able to inhibit the precipitation of calcium bilirubinate and the coexisted choric acid enhances this effect.The effect of EHDPon the particle size was also studied with Coulter counter. The results show that EHDPinhibit the aggregation effectively and a strong synergic effect was observed between EHDP and choric acid.
    Studies on the Hydrolytic Polymerization of Chromium (Ⅲ) Ion(Ⅹ) --Graphing Analysis and Computer Screening for Determination of Hydrolysis Model
    Luo Qinhui, Shen Mengchang, Ren Jianguo, Ding Yi, Dai Anbang
    1988, 9(12):  1211-1216. 
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    The hydrolytic polymerization state of Cr3+ was studied in the presence of maleic acid by equilibrium pHmethod at 60℃ and constant ionic strength with total concentration of Cr3+ to be 0. 0080mol·dm-3 and that of maleic acid to be 0.0100, 0.0120, 0.0140mol·dm-3 respectively. Preliminary estimation for composition of the system was made by graphing integration and then precise calculation was made by pqr analysis on the basis of the former. Results showed that the present system is composed of [Cr(OH)A],[Cr2(OH)A]3+ ,[Cr2(OH)A2]+ and a small amount of [CrA2]-,and is more complicated than 1:1 system.The equilibrium constants of twelve reactions were obtained by calculating thirty one data points with good fitting. Comparison between the present system and that with fumaric acid was made.
    Synthesis, Characterization and Structure of Complex [Sc(NO3)3(H2O)2]·(Benzo-15-Crown-5)
    Tan Minyu, Gan Xinmin, Tang Ning, Zou Jinping, Zhu Ying, Wang Xin
    1988, 9(12):  1217-1221. 
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    The single crystal of the complex [Sc(NO3), (H3O)2[·(B15C5) has been prepared and characterized by elemental analyses, 1Rspectra and molar conductance. The structure of the complex is determined by X-ray single crystal diffraction analyses. The crystal of the complex is monoclinic, space group P21/n with cell parameters: a = 9.405(6), b=15.569(8), c= 15.896(2) Å,β = 95.92(1)°, V = 2315.5Å3,Z = 4, Dc = 1.538/cm3, D0= 1.54g/cm3. The structure has been refined to R = 0.051 and Rw = 0.055 using< 3172≥3σ(Ⅰ) observed data. Here the crown is not coordinated to the metal ion but is linked to the [Sc(NO3)3(H2O)2] molecule by O...H-O bonds. The Sc-Obond lengths are 2.158(3)-2.254(3) Å for nitrato-and 2.123(3)-2.143(3) Å for water oxygens.
    The Study of Atomization Process in Graphite Furnace Atomizer(Ⅴ)——Influence of Perchloric Acid on Absorption Signal of Lithium and Germanium in Graphite Furnace
    Zheng Yansheng, Zhang Dalei
    1988, 9(12):  1222-1226. 
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    In this paper the influence of perchloric acid on absorption signal of lithium and germanium in graphite furnace was studied in detail. It was found that a suppression effect of perchloric acid on absorption signal of lithium wasShown.The suppression efiect is due to the formation of Lid originating from ther vapor phase reaction. The interference of .residual peichloric acid is eliminated at temperature of thermal pretreatment higher than 2000℃. The interference of perch-loric acid can be removed by adding NH4NO3 rrior to the decomposition of perchloric acid. The influence of perchloric acid on absorption signal of germaniumis closely related to ash temperature. The enhancement effect of perchloric acid is slowly increased with the raise of the temperature prior to 500℃, but obviously increases at temperatures higher than 500℃. The mechanism of interference is discussed as well.
    Studies on Electroanalytical Characteristics of Complexes of Copper (Ⅱ) with 2-QADNm
    Zhang Zhengqi, Yu Ruqin
    1988, 9(12):  1227-1232. 
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    The polarographic and other electroanalytical behavior of complexes of copper(Ⅱ) with 4-(2-quinolylazo )-1,3-dihydroxynaphthalene (2-QADNm) has been studied by pulse polarography,A Cimpedance measurement and cyclic voltam-metry. Using polarographic wave of Cu(2-QADNm)2 complex at -0.79V,the trace copper down to 10-8mol/L can be determined. Asingle-sweep polarographic procedure for determination of copper using 2-QADNm as the reagent has been worked out.
    Neutralization Titration with Metal Electrodes (Ⅰ)——Zero-Current Oscillographic Potentiometric Neutralization Titration on Two Indicator Electrodes
    Xie Yuanwu, Gao Hong(H. Kao)
    1988, 9(12):  1233-1236. 
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    Zero-current oscillographic potentiometric neutralization titration on two indicator electrodes was studied. Any combination of two electrodes from Hg(Ag), Pt (anodized in 0.1mol/dm3 H2SO4 at 1.5V vs. S C E), Sb and W(soaked in distilled water) can be used for 0. 1~0.01mol/dm3 acid-base titrat-ions. For more dilute acid or base solutions, one can use an anodized electrode and an unanodized one. Polyacid can also be titrated. Compared with other methods,this method is simple, accurate, intuitive, rapid and sensitive. The effect of Cl- on Hg(Ag), Pt electrodes during the titration is also discussed.
    Studies on the Dual-system and Double-wavelength Spectrophotometry ——Simultaneous Determination of Nb and Ta
    Shi Huiming, Li Jinhe, Xi Changsheng
    1988, 9(12):  1237-1241. 
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    Asensitive and selective method for the simultaneous determination of Nb and Ta in alloy steel, which is based on the basic principle of the dual-system and double-wavelength spectrophotometry, has been developed. SAPand 5Br-PADAP were chosen for constructing "the pair of coloured system", and Nb and Ta were quantified by the formulas: △ANb =A5Br-PADAP,604 - 0.28ASAF,513 △ATa=ASAF,513 -A5Br-PADAP,615 respectively. The present method has a high sensitivity (△εTa = 1.35 ×105, △εNb =1.33×105), and most of common ions do not disturb the determination of Nb and Ta.
    Analysis of Organometallic Compounds(ⅩⅤ)——Study on the Relationship Between the Rf Values of Thin Layer Chromatograph and Infra-Red Spectral Absorption of Some Rare Earth-Metal Binuclear Organometallic Compounds
    Li Songlan, Yang Xuejin, Sun Yuewen, Li Ping, Wang Xukun, Zhou Xiaoxin
    1988, 9(12):  1242-1245. 
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    Aseries of rare earth-metal binuclear organometallic compounds with the general formulae [(C6H5CO)2CH]2 Re-Fe (or Mo) (CO)2(π-C5H5), [(C6H5CO)2CH]2 Re-Sn(G6H5)3 have been separated successfully by TLCusing silica-gel as absorbent and xylene-absolute alcohol-petroleum ether (1:1:20, 1:0.4:20 and is 0.5:20) as development. The minimum detectable quantity is 0.01649mg per millitre soluticn of determined binuclear organometallic compounds.
    Synthesis of 4,5-Dioxo-(2-Thio)-1,3,2,4-Diazadiphosphplanes
    Chen Ruyu, Cheng Leifeng
    1988, 9(12):  1246-1251. 
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    Twenty two hew compounds with the general formula:   have been prepared through the cyclization of alkyl N-alkyl alkylcarbamoylphos-phonamidates with (4-substituted)phenyl dichlorophosphines in the presence of triethylamina and then sulfurization by sulfur. One of these syntheses, in which 6 was obtained by direct sulfurization without the separation of 5, was used.The structures of the products were proved by 1H, 31P NMR, IR, MSandelemental analysis. 31PNMR chemical shift differences ΔδP and IR wavenumberdifferencesΔvP=s showed themselves to correlate with the Taft constant (σ0).respectively This finding was discussed in terms of possible (p→d)π backbonding. It was found that some of these compounds have herbicidal and fungic-idal activities.
    The Refractive Regularities of Some Phosphatic Solutions to Laser
    Yu Xiling, Shao Zongshu, Wang Ruihua
    1988, 9(12):  1252-1256. 
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    he laser refractivity of KH2PO4, KD2PO4, NH4H2PO4 solutions and H2O, D2O have been studied in detail by abbe refractometer. The temperature coefficients of their refractive indices and the dispersive power to laser and natrium light, have been accurately measured. The relationship between different concentrations of the solutions and the refractive index are determined. The refractive regularities of some saturated solutions are presented separately. Using the laser-fringe method, the saturated data of the corresponding .solution are also determined precisely. The refractive indices of these medium to He-Ne laser are less than those to natrium light. The refractive indices of D2O are less than those of H2O. The refractive indices of the solutions increase linearly with the increasing of the concentration. The higher the concentration of the solution, the stronger the dispersive power of the refractive index. As for the solution with definite concentration, the refractive index decreases linearly as the temperature rises. The temperature coeffcients of the refractive indices of these mediums range from 0.00010 to 0.00016.
    The Effect of TO4 Tetrahedral Electric Charge in Molecular Sieves
    Hou Jun, Guo Chunxiao, Xu Ruren
    1988, 9(12):  1257-1262. 
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    Based on the results of the gas-solid reactions between AlCl3(PCl3) and APO-5 molecular sieve, we have investigated the electric and energetic factors in the isomorphous substitution reactions of the aluminosilicate zeolites and aluminophosphate molecular sieves. By comparison of the applications of Loewenstein's rule and Pauling's electrostatic valence rule to molecular sieves, we can conclude that the nature of Loewenstein's rule is electrostatic and limited, however, might it restated as linkages of two TO4 tetrahedra with the same kind of charge (positive or negative) in molecular sieve framework are not present. The quantum chemical calculation verifies the validity of the above conclusion.
    An MNDO Study of the Gyclpaddition Reaction of Garbene with Butene
    Yan Deyi, Su Shuangquan, Tang Dinghua
    1988, 9(12):  1263-1267. 
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    The reaction pathways of singlet and triplet carbens with ethylene, cis-2-butene and trans-2-butene have been studied by means of MNDO. metho. The reasonable explanation of either cis- or trans-2-butene with triplet carbeneto form the mixtrue of cis- and trans- 1,2-dimethyl cyclopropane has been given, The. reaction activation barriers of singlet carbene with cis- and trans-2-butene, using MNDO-CIcalculation, are 53.05. and. 57.23kJ/mol, respectively. The reaction mechanism is discussed briefly in the light of frontier orbital theory.
    Synthesis of Bis(Alkenylcyclopentadienyl) Titanium(Zir-conram)Polyethers by Interfacial Polycondensation
    Shen Hongkang, Wei Rongbao, Liang Ya, Lin Lin, Xue Qifeng, Chen Xiaojin, Meng Zhaoquan
    1988, 9(12):  1268-1272. 
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    Bis (Alkenylcyclopentadienyl)Titanium(Zirconium) dichlorides werereacted with diphenols through interfacial polycondensation to give a series of16 new polymers. IK, TG/DTG, solubility and mol. wt. determinations weremade. The relationships between experimental parameters and,molecular weight werediscussed.
    Study on Polyethylene by Wide-Angle Scattering(Ⅰ)
    Wu Faxiang, Cai Baolian
    1988, 9(12):  1273-1276. 
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    In this paper, Hv light scattering patterns of polyethylene spherulites with; concentric-circle extinction are examined by wide-angle laser scattering instrument. The cause of formation of the wide-angle scattering patterns is ex-plained, and twisted phenomena of lamellae are explored by using the model of effective dipole moment. The theoretical analysis is in agreement with the experimental result.
    Studies on the Synthesis, Characterization and Polymer-ization Kinetics of Polyamide-poly-Ⅲ-caprolactone Multiblock Copolymers
    Xu Linyun, Wang Hui
    1988, 9(12):  1277-1281. 
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    The polyamide-poly-Ⅲ-caprolactone multiblock copolymers consisting of nylon 1010 as hard segments and poly-Ⅲ-caprolactone as soft segments were synthesized from ω,ω'-dicarboxylic nylon 1010 oligomers with ω,ω'-dihydroxy poly-e-caprolactone oligomers in the presence of catalyst by melt polycondensation. These block copolymers were characterized by molecular weight determination,1HNMR and DSC methods. The kinetics of polycondensation of ω,ω'-dicarboxylic nylon 1010 oligomers and ω, ω' -dihydroxy poly-Ⅲ-caprolaetone oligomers has been studied at various temperatures. The experiments showed that the reaction is. of 2nd order, the activation energy ΔE = 58.2 kcal/mol and the reaction kinetic constant K =1.36×l022·e-2.93×104/T.
    The Investigation on Polyurethane/Polyepoxide Resin Interpenetrating Polymer Networks(Ⅱ)
    Li Yuwei, Wang Jingyuan, Li Yiming, Zhang Limei, Tang Xinyi
    1988, 9(12):  1282-1284. 
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    A series of polyurethane/polyepoxide resin (PU/EP = 50/50) interpenetrating polymer networks (IPN) was prepared. The sample of each type differed in the molecular weight (Mw) of the polyol, 30H/2OHratio and NCO/OHratios in the PUcomponet. The extent of mixing of the components in these IPNwas investigated by using electron microscopy, dynamic mechanical analysis and tensile testing. The results show that the extent of interpenetration can be improved by decreasing the Mw of the polyol and increasing the 3OH/2OHratio, NGO/OHratio in the PUcomponent.
    Synthesis of Large Single Crystals of Ti-ZSM-5 and B-ZSM-5
    Qiu Shilun, Pang Wenqin, Ma Shujie
    1988, 9(12):  1285-1286. 
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    The large single crystals of silica-rich, Ti-, B-ZSM-5 type zeolitescalled Titanozeosilite and Borozeosilite were synthesized in non-alkaline medium inthe presence of fluoride. The mechanism of the crystallization for the singlecrystals was investigated in the systems of SiO2-TiO2-(TPA)2O-NH4F-H2O and SiO2-B2O3-(TPA)2O-NH4F-H2O.
    Reduction of Sulfoxides with Combined Reducing Agent Ferric Chloride/Sodium Borohydride
    Lin Ronghui, Zhang Yongmin
    1988, 9(12):  1287-1289. 
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    Under mild conditions various sulfoxides were reduced to sulfides by combined reducing agent ferric chloride/sodium borohydride in excellent yields. The reduction mechanism was also discussed.
    Studies on Electrochemical Analysis of Precious Metals(Ⅷ) --Determination of Trace-Platinum by ASV
    Zhang Yuxiang, Lu Fan, Zhang Zhide
    1988, 9(12):  1290-1292. 
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    A new method of determination of trace-platinum by anodic stripping voltammetry (ASV) has been established. By using the cotton cellulose xanthate (CCX) separation column to separate the main impurities of Au3+, Pd2+, etc, the filtrate of sample was treated by aqua regia and controlled in the optimun supporting electrolysis system of 0.3mol·L-1H2SO4-Hg(Ⅱ)-3.0 × 10-4mol·L-1 KMnO4 for the purpose. The detection limit of Pt was 0.5ppb. The method was applied to the determination of platinum in several complicated samples, such as industrial waste water, refined mineral and chloridized residue. Its coefficient variations were 0.086, 0.041 and 0.027 respectively. The recovery of platinum in industrial waste water was in the range of 92~104%.
    Studies on Some Reactions of Sulfur-Containing Carbanions and Their Synthetic Applications (Ⅰ)——A Solid-Liquid Phase Transfer Catalyzed Synthesis of Substituted Cinnamates
    Liu Guangjian, Zhang Zheng, Xu Congying
    1988, 9(12):  1293-1295. 
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    This paper reports a solid-liquid phase transfer catalyzed alkylation elimination of methyl α-phenyl sulfinylacetate and its application for the synthesis of substituted cinnamates. Some improvements have been made in the generation and synthetic application of this α-sulfinyl carbanion by using potassium carbonate as base and Aliquat-336 or TEBAas catalyst. The present procedure provides a convenient and efficient approach to a numoer of α,β-unsaturated esters under mild conditions.
    Some Reactions of α, ω-Diiodoperfluoroethane and α, ω-Diiodoperfluorobutane
    Mei Huanmou
    1988, 9(12):  1296-1298. 
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    The fluoroalkylation of iodobenzene with α,ω-diiodoperfluorobutane (Ⅱ) in the presence of copper gave ω-iodoperfluorobutylbenzene. After etherific-ation with substituted thiophenol under UV, it afforded suitable bisthioethers. When α,ω-diiodoperfluoroethane (Ⅰ)was used, no such products were obtained. The treatments Of (Ⅰ) and (Ⅱ) with 35% H2O2 and (CF3CO)2O yielded corresponding iodonium compounds with good yields.
    A New Method for the Preparation of Alkoxymalonic Esters
    Wang Chuan, Li Ji, Ye Xiulin
    1988, 9(12):  1299-1301. 
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    Alkoxymalonic esters are useful reagents in organic syntheses, but most, of the methods for their preparation found in the literatures[1-7] are of restricted applications, and in some of these methods the yields are unsatisfactory, the starting materials are not readily available, or the procedures for preparation are somewhat tedious. In order to improve such a situation, a general applicable new method with a good yield (mostly over 75%) has been proposed. The reaction is carried out with an alcohol ROH (or a phenol) and an alkyl (R') bromomalonate in the presence of triethylamine where R' should be equal to Rfor preventing transesterification and mixed alkoxylation. But ethyl bromomalonate is quite feasible in the preparation of phenoxymalonate because transesterification product has not been isolated.
    The Electrochemical Reduction of 3-Methyl-4-Amino-5-Nitroso-Uracil
    Zhang Wenzhi, Wu Xizun
    1988, 9(12):  1302-1304. 
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    This paper reports an experimental study pn the electrochemical behavior of 3-methyl-4-amino-5-nitrosouracil (3-MU) at bright platinum electrode in sulfuric acid solution. The process involving a reduction was established by means of cyclic voltammetry and constant current step methods. Electron spin resonance (ESR) spectroscopic method was used for the detection of intermediates. The results showed that radicals were generated during the reduction process. Based on data analysis a mechanism of the electrochemical reduction of 3-MUis proposed at the region of low overpotentials.
    Study on the Extrapolating the Dynamic Interfacial Tensionifor Solution of Surface Active Substance to Determine the Equilibrium Interfacial Tension
    Xu Xiukun, Wang Shirong, Wu Shusen
    1988, 9(12):  1305-1307. 
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    J.Kloubek used the empirical equation 1/(δH2O-δt)=b/(At1/2)+1/A to correlate his experimental data in a 1/(σH2O-σt)vs(1/t1/2). It is possible to determine the static surface (interfacial) tension for solution, but the results were approximately in agreement with the literature.The article gives the theoretical derivation of the empirical equation and discusses the cause of deviation. A further investigation leads to use a extrapolating, the static surface tension is better than empirical equation.
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