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    24 November 1985, Volume 6 Issue 11
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    Articles
    Studies on Trasformation of Zeolite Crystals (Ⅲ)--The Stability of Zeolite NaY and the Structure of Zeolite NaPc
    Ma Shujie, Li Liansheng, Xu Ruren, Ye Chaohui
    1985, 6(11):  951-956. 
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    We investigated the crystallization of NaYand especially the transformation of NaYto NaPtype zeolite from an initial gel of batch composition 3.3Na2O·Al2O3· 10SiO2·200H2Oat 100℃. We found that there are three stages in the whoie process: the nucleation and crystal growth of NaYtype zeolite, the nucieation of NaPand the dissolutian of NaYand the crystal growth of NaPtype zeolite.In order to investigate the mechanism of this process.We proved the formation of nuclei of NaYand NaPtype zeolites in liquid phase by using the electron diffraction technique. We used the electrom micrograph, X-ray diffraction, TMS-GCand(HRMAS) solid state Si-29NMRtechnique comprehensively to investigate the changes of particle size and morphology of zeolite, the existing species and their distribution of poly-silicates in liquid and solid phases and the change of zeolite structure in the process of transformation of NaYto NaPc. Amore detailed liquid phase transportation mechanism of transformation was suggested.
    On Some Binary Systems of Alkali Earth Metal Fluoride Halides
    Lin Jianhua, Su Mianzeng
    1985, 6(11):  957-962. 
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    The fluoride halides of barium and strontium BaFCl, BaFBr, BaFI, SrFCl and SrFBr, as well as some binary systems of them BaFCl1-xBrx (Ⅰ), BaFCl1-xIx (Ⅱ), BaFBr1-xIx(Ⅲ), SrFCl1-xBrx (Ⅳ), and Sr1-xBaxFBr(Ⅴ) were synthesized by the method of solid state reaction at high temperatures. Among them BaFIwas prepared by the reaction of NH4Iwith BaF2 at 400℃ for the first time.Phase diagrames and the subsolidus phase relationships of these binary systems have been studied by thermal analysis and by the method of lattice parameter determinations respectively. Ⅰ, Ⅲ and Ⅳ are systems of completely miscible solid solutions with a minimum melting point. Ⅱ and Ⅴ are systems of binary eutectic. There exists a correlation between the type of phase diagrames of these binary systems and the relative difference of c/a of the constituents, of which the system consists.
    Studies on the Pulse Polarography of Flavin Mononucleotide and It's Measurement of Rate Constant at the Mercury Electrode
    Song Hongzi, Wang Naixing, Zhang Zuowu
    1985, 6(11):  963-966. 
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    The differential pulse polarographic behaviour of flavin mononucleotide (FMN) and determinative conditions have been investigated. The optimum conditions for the determination of FMNare as fllows: the clectrolyte was 0.01Msodium citrate (pH5), initial potential -0.100V (vs.Ag-AgCl), final potential - 0.600V(vs·Ag -AgCl), voltage sweep rate 100mV/sec. Afair reproducibility was obtained in the above progedure and a good proportionality between the values of the peak current and FMNconcentration (1.8×10-6-4.7×10-5M) has been observed. The decection limit is 6.8×10-7M. This method provides a rapid and simple way to determination of FMN.This paper also reports that the application of cyclic voltammelry to study electrode process kinetic behavior has been established. Under the experimental conditions the rate constants for electron transfer arc determined. The values of k arc in good agreement with literature's results.
    The Determination of Individual Rare Earth in the Binary Mixture of Gd and Y by Rate Differential Kinetic Method
    Chen Danhua, Cai Ruxiu, Lin Zhixin, Zeng Yun'e
    1985, 6(11):  967-971. 
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    The kinetic behaviour in the substitution reaction of RE(TCA)2 (TCA=2-(2-arsenophenylazo) - 7 - (2,4,6-trichlorophenylazo) -1, 8-dihydroxynaphthalene-3,6-di-sulfonic acid) with CyDTAhas been studied, and some kinetic parameters of the reaction system and kinetic equation for determination have been measured and established. Gd and Yin the binary mixture have been determined by their rate difference in the ligand substitution reaction of RE(TCA)2 with CyDTAat pH3.01 Anumber of synthesized samples was analysed by logarithmic extrapolation method with good sensitivity and high precision, and it is simple and rapid.
    The Influences of Secondary Ligand and Organic Solvent on the Mixed Ligand Complexes in the System of "Titanium(Ⅳ)-5-Pyridylazo Dye-L"
    Wen Meijuan, Shao Guangdi, Chen Huaxu
    1985, 6(11):  972-976. 
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    The influences of secondary ligand and organic solvent on the mixed ligand comple-xes in the systems of "Titanium(Ⅳ)-5-Br-PADAP-Sulphate", "Titanium(Ⅳ)-5-Br-PADAP-Pyrocatechol" and "Titanium(Ⅳ)-5-Br-PADAP--Hydroxylaminc-Chloroacet-ate" were reported.The composition ratio among their constituents in the three systemsare l:1:2, 1:3:2 and 1: 1: 1: 1, respectively. It was shown by the electropheresis and ion-exchange, that these complexes were all electrified and the first one was a complex anion and the latter two Were ion-pairs formed by associa,tion between thecomplex cation and anion. The concentration ranges in which they obeyed to Beer's law were also reported.
    Study on Color Reaction of Ternary System of Mercury-meso-Tetra (P-Sulfonatophenyl)-Porphyrin-Cetyltrimethylammonium Bromid
    An Xinmin, Liang Yongwu, Jia Dianzeng, Zhang Xiangdong
    1985, 6(11):  977-979. 
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    Ahighly sensitive colour reaction of mercury(Ⅱ)-meso-letra (P-sulfonatophenyl) porphyrin(TPPS4)-cctyltrimethy]ammonium bremicc (CTMAB) system has been investigated spectrophotometrically. Mccury reads rapidly with THS4 and CTMABto form a yellow-green ternary complex at pH = 11 under room temperature. The apparent molar absorptivity of the complex is 2.38×105 l·mol-1 ·cm-1 at 445 nm. The molar ratio of the complex has been estimated to be Hg:(TPPS4)= 1:1.
    Sensitive Spectrophotometric Determination of Uranium(Ⅵ)with 4,5-Dibromophenylfluorone and Tween-60
    Wang Dongjin, Xiao Zijing, Wu Peiren, Pan Qinhong
    1985, 6(11):  980-982. 
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    Ahighly sensitive method for spectrophotomctric determination of uranium(Ⅵ) has been developed. Uranium(Ⅵ) reacts with 4, 5-dibromophenylfluorne(Br-PF) in the prcsence of Tween-60 to form a red-violet coloured complex with molar ratio of Uto Br-PF 1:3 at pH6.5-9.0. The apparent molar absorptivity of the complex is 1.79 × 105 L. mol-1. cm-1 at 565nm. Beer's law is obeyed in the range of 0-5μg U(Ⅵ)/10ml. Metal ions interference can be eliminate by a preliminary extraction of U(Ⅵ) with trioctylamine from 4.5N HCl. This method has been applied to determination uranium in ores with satisfactory results.
    Determination of Trace of Cyanide in Enviromental Sample by G. C.
    Guo Yaxian, Ding Zhongtian, Chao Xiangfa
    1985, 6(11):  983-985. 
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    Anew procedure of determination of cyanide is described. The method is simple, reproducible, accurate, and speed up.
    Differential Pulse Anodic Stripping Voltammetry of Trace Se on a Tubular Guld Electrode
    Wan Zhen, Chen Qiang
    1985, 6(11):  986-988. 
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    The differential pulse anodic stripping voltammetric determination of trace Se in water using a flow-through cell with a tubular gold electrode was reported. The tubular electrobe was easy to be constructed and operated, and reguired only small volume of sample. The signal obtained was stable and high reproducible. In a medium of 0.8Msulfuric acid, a sensitive stripping peak of Se at +0.88v(VS S. Ag/AgCl) was observed. The detection limit was showen to be 0.02ppb.Alinear dependence of peak height on concentration of Se over a range of 10-10 to 10-8 g/ml was also observed. It was used to determine trace selenium in water with satifactory result.The current-concentration equations for the differential pulse anodic stripping voltammetry on a tubular electrode have been theoretically derived and experimentally verified.
    The Mass Spectra of Heterocyclic Conjugated Componds and Their Quantum Chemical Calculations
    Fang Yaoren, Lai Zhugen, Liang Desheng, Lu Fengcai
    1985, 6(11):  989-994. 
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    Amechanism of clevage-rate-determining-step in the mass spectra of furfurol, furylacrylic acid, dimethylfuran, thiophene-2-aldehyde, and pyrrole-2-aldehydc is proposed. Various quantum parameters of molecular ions together with their fra-ments of these compounds are calculated by CNDO/2 method. The peak-heights of the mass spectra can be quantitatively interpreted. This method may be extended to heterocyclic conjugated compounds.
    Study on the Carbonyl Substitution in Bis (μ-Alkylthio)-Hexacar-Bonyldiirons--The Synthesis and Structures of Triphenylphosphinc Fc-S Clusters(μ-RS)(μ-R'S)Fc2(CO)5Pph5)
    Song Licheng, Hu Qingmei, Wang Jitao
    1985, 6(11):  995-999. 
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    Fourteen new Pph3-substituted Fc-Sclusters with general formula (μ-RS)(μ-R'S)Fe2(CO)5 Pph3 have been synthesized by the reaction of unsymmetrical type of bis(μ-alkylthio)-hexacarbonyldiirons with triphenylphosphinc. Their m.p., IR, 1HNMRand C/Hanalysis have been performed. Based on the analysis of the influence of Pph3 on vco and δ-alkyl, the spacial orientation of Pph3 in these clusters has also been established.
    A Study of the Thermal Elimination of Quaternary Ammonium Hydroxides——On the Conformation Rule for Hofmann Elimination
    Guo Jing, Lu Duren, Ye Xiulin
    1985, 6(11):  1000-1004. 
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    It is known that there are many examples of the thermal elimination of quaternary ammonium hydroxides which do not follow the Hofmann rule. Based On the expermental data reported in the literature, Ye, one of us, and Zhu found that the orientation of the elimination reaction is chiefly determined by the preferential. con-formation of the reactant rather than by the acidity of the β-hydrogen atoms of the alkyl groups and a "conformation rule" was proposed for the elimination of quaternary" ammonium hydroxides[2]. However, when these two rules, the classical Hofmann rule and the conformation rule, are cmployed, one occasionally gets different or even contradictory predictions. In order to contrast the two lulcs one with the other in their reliabilities, eight quaternary ammonium hydroxides were prepared and subjected to the elimination reaction. The experimental results obtained (shown in Table 1) are all in good agreement with the conformation rule, but only partially with the Hofmann rule, in other words, the conformation rule is superior and acceptable.
    Synthesis of Some 2-Phenyl-5-(β-Styryl)Furan Derivatives
    Li Zhongjie, Ma Huarang, Zhou Yun, Cao Jiuju, Luo Wehbo
    1985, 6(11):  1005-1008. 
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    Sixteen 2- phenyl-5-(β-styiyl)furan derivatives had been prepared by Wittig rea-ciion from corresponding substituted o-phcnylfurfutal and bcnzylphosplonium salt The structure of all products were cetermined by quantitative clementary analysis, DTA, JR, UVand. 1H NMR, The fluorescent properties were measured as well.
    Quantum Chemical Study of Simulating Doped Polyacetylene
    Cao Yang, Tao Fuming
    1985, 6(11):  1009-1013. 
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    The model ring systems of cluster (H5Li)4 were used to simulate the doped Polyacetylenc, and computed by ab initio restricted Hartree-Fock self-consistent field molecular orbital method.We obtained the changing rules of values such as total energyies, energy levels, bond orders, etc.and thus; explained the changing rules of geometrical structure and band structure, insulator-metal transition and electric conducting mechanism of the doped polyacetylene.
    A Theoretical Study of Mechanisms in the Photochemical Reactions of Forming Ketene After the α-Bond Rupture in Cyclohexanone
    Yu Hengtai, Sevin Alain
    1985, 6(11):  1014-1018. 
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    ab initio SCF + CIcalculations of the potential energy surfaces and barriers in the various paths are presented for the chemical reactions of forming ketene after the α-bond rupture in cyclohexanone, using acetaldehyde as model. The possibilities of the various paths and the transition states are discussed.
    Theory of Boundary on Isopleth of Multicomponent Phase Diagrams (Ⅰ)——Regular Section
    Zhao Muyu, Kang Hongye
    1985, 6(11):  1019-1024. 
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    The relation between the characteristics of boundaries and combinations of the phases in neighboring phase regions on the regular isopleth of an isobaric multicomponent phase diagram has been discussed systematically with the aid of the theory concerning the relation between neighboring phase regions and their boundaries[2].
    Infrared Study of Chemisorption and Conversion of Tert-Butanol on H5PMo10V2O40/SiO2 Catalyst
    AVu Tonghao, Yang Hongmao, Wang Guojia
    1985, 6(11):  1025-1029. 
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    The chemisorption and catalytic conversion of tcrt-butanol have been investigated by means of FTIR. At 15℃, chemisorption of tert-butanol has been found to occur on the catalyst surface, the probable chemisorbed state being (CH3)3C, π-allyl-like species CH2=C(CH3)=CH2 and σ-allyl species CH2C(CH3)=CH2. At 50℃, this π-allyl-like species desorbed to give gaseous isobutene.
    The Effect of CaO Modification on Selectivity of ZSM-5 Zeolite
    Wu Suochuan, Fen Xinghong, Zhou Rixin
    1985, 6(11):  1030-1032. 
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    The effect of CaOmodification on the selectivity of ZSM-5 was studied. The selectivity of the modified catalyst toward dimctyl benzene in the aromatzation of propenc and the methylation of tolune was increased by a factor of 2.7 and 1.6 respectively in relation to the unmodified one.The calculation based on the window model was made for the charge density of the carbon atom in tolune when on the modified and unmodified catalyst.The results show that the charge density for the para-carbon atom of tolune is largely increased in the CaOmodified ZSM-5 and the energy in I3 position is the lowest,thus favor the electrophilic reactions.This explains the improved selectivity toward dimethyl benzene of ZSM-5 upon CaOmodification.
    Studies on the Joined Device of Microreactor-Gas Chromatography-Differential Thermoanalysis and the Kinetics of Oxidative Dehydrogenation of Ethanol to Acetaldehyde over Silver Catalysts
    Zhu Jing, Fung Fusheng, Xiang Yifei
    1985, 6(11):  1033-1035. 
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    The combined device of microreactor-gas chromatography-DTAis designed to study the catalytic reaction kinetics. With the device the data of reaction kinetics of ethanol over electrolytic silver catalysts have been measured. The conversion of cthanol is<5%. The oxidative dehydrogenation of ethanol is zero order to oxygen and 1.08 to ethanol while no side reaction take place, and the activation energy is 18.5 kcal/mol.
    Study on Polyepoxide/Polyethylacrylate Intercrosslinking Interpenetrating Polymer Network(Ⅰ)——Morphology and Dynamic Mechanical Behavior
    Ma Rongtang, Ma Song, Wang Jingyuan, Li Yuwei, Wang Yan
    1985, 6(11):  1036-1038. 
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    Intercrosslinking simultaneous interpenetrating polymer networks have been synthesized from epoxide resin, ethylacrylate monomer, and crosslinking agents and characterized by means of SEM, IR, and TPA. The amount of intercrosslinking agente was found to effect profound in morphology and dynamic mechanical behavior of IPNs. At higher level of intercrosslinking, two-phase morphology disappeared and a higher damping value was observed in a broad temperature range.
    Rheometric Study on the Dispersity of γ-Fe2O3 Suspensions
    Ma Jiming, Xu Yong
    1985, 6(11):  1039-1044. 
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    In present work the viscosity of suspensions of γ-Fe2O3 particles in polymer solutions have been measured as a function of concentration at shear rates Dfrom 21.2 sec-1 to 571 sec-1. The intrinsic viscosity,[η] ,derived from the concentration dependence of the viscosity by using Mooney equation, was found to decrease with increasing shear rate. The floc size, estimated from the [η] and a theoretical treatment of floc growth by vold, was consistent with the result obtained from sedimentation ratcs. The effects of various polymer adhesives and surfactants on the dispersity of suspensions were determined. It was found that, the intrinsic viscosities of γ-Fe2O3 suspensions containing different polymer adhesives showed a great divergence at low shcar rate, but reached an about the same value at infinite shear rale. The addition of surfactants decreased the [η]∞, but increased slightly the [η] at low shear rate. Astructural model of the floc was proposed to interpret the experimental results.
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