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    24 September 1988, Volume 9 Issue 9
    Articles
    Studies on the Synthesis, Structure and Properties of Manganese Aluminophosphate Molecular Sieve
    Han Shuyun, Zhou Jianrong, Guo Ye, Zhou Fengqi, Wang Ping
    1988, 9(9):  871-875. 
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    The pure Manganese Aluminophosphate molecular sieve was synthesized. The structure of Manganese Aluminophosphate molecular sieve MnAPO-5 wasinvestigated by means of X-ray diffraction, electron paramagnetic resonance Spectrum, infrared spectra and electron probe energy dispersion analysis. The results of infrared spectra and parameters of the unite cell show that the struct-ureof MnAPO-5 is of the AlPO4-5 type. The study of EPR, electron probe energy dispersion analysis and chemical composition of MnAPO-5 indicate that manganese enter into the framework of MnAPO-5 molecular sieve. The adsorption properties, thermal stability and surface acidity were investigated.The results show that MnAPO-5 has excellent physical and chemical properties.
    Studies on the Redox Properties of Molybdovado Phosphoric Heteropolyacids Having Dawson Structure
    Wang Enbo, Gao Lihua, Liu Jingfu, Liu Zongxu
    1988, 9(9):  876-880. 
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    The redox properties of molybdovanadophosphoric acid H6+n[P2Mo18-nVnO62]·H2O(n=1~3) and H4+n[P2Mo13-nVnO62H2]· H2O(n= 4,5) in solution were studied with potentiotitrimetry and polarography and cyclic voltammetry. The three reduction steps for the five heteropolyacids involving n, 2, 2 electrons accompanied by the addition of n, 2,2 protons were ascertained. The correlograms of the cyclic voltammogrammetric peak potentials versus pHwere obtained and the reduction mechanism has been proposed.
    Application of Chemical Oscillating Reaction to Chemical Analysis——B-Z Reaction System for Determination of Tl(Ⅰ) and Hg(Ⅱ)
    Liang Yizeng, Yu Ruqin
    1988, 9(9):  881-885. 
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    The application of chemical oscillating reactions to chemical analysis was investigated. It was found that Belosov-Zhabotinsky reaction system is a dynamic de.ter-mination system of good selectivity and sensitivity to thallium(or mercury)ions. The change of the period of oscillating curve of B-Zreaction is linearly proportional to the amount of Tl(Ⅰ)(Hg(Ⅱ)) existing in the system, which can be used to determine 0.08~10 ppm Tl(Ⅰ)(or Hg(Ⅱ)). The mechanism of this analysis system is discussed by means of the Monte Carlo simulation technique, and the results agreeing with the experimental fact were obtained.
    Tetraalkyitin Neutral Carrier-Facilitated Transfer of Nitrite Ion Across Bulk Liquid Meinbranes
    Wang Kemin, Yu Ruqin
    1988, 9(9):  886-890. 
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    The transfer of nitrite ions through bulk liquid membrane mediated by tetra-alkyltin carriers was studied experimentally.The length of the carbon-chain in the car-rier molecules has substantial effect on the NO2--transfer, which is closely related to the response characteristic of the nitrite-sensitive electrodes prepared by the use of thesecarriers. The effects of the concentration of tetraalkyltin and nitrite ion, and the nature of counter ions on the transport rates of nitrite were studied.The relationship between these phenomena and the properties of electrodes based on tetraalkyltin carriers are discussed.The experimental results are interpreted in terms of the ion-pair mechanism, of neutral carrier-mediated ion transport.
    Investigation on Triangular-wave AC Oscillopolarography(Ⅲ)——Theory of Two Components
    Qi Hong, Ma Xinsheng, Gao Hong(H. Kao)
    1988, 9(9):  891-896. 
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    Theory of triangular-wave oscillopolarograms in the solution containing two depolarizer has been derived from the stepwise application of initial conditions' The result can be returned to what obtained by one depolarizer, which makes an agreement with expeiment. Factors affecting the incision are discussed.
    High Sensitive Synergistic Chromophoric Reactions by Double Chromogenic Reagents——Molybdenum-Bromopyrogallol Red-Ethyl Violet System
    Shen Hanxi, Liu Yuelong
    1988, 9(9):  897-901. 
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    In the presence of polyvinylalcohol molybdenum ions(Ⅵ) can form a colour product with both bromopyrogallol red and ethyl violet. Owing to the increasing of the effective absorption section area of chromogenic molecules, the reaction sensitivity is enhanced remarkably. This paper describes the experimental conditions of above mentioned synergistic chromophoric reaction, composition of complex formed and related reaction mechanism, and a procedure for the spectroph-otometric determination of trace molybdenum. In an acetic acid medium molybdenum ions form an ion-associate complex with a definite composition of Mo:BPR:EV = 1:1:2, with both Bromopyrogallol red and ethyl violet, and its corresponding molecular form is [EV]2 [MoO2(BPR)]. The maximum absorption of molybdenum complex was located at 535 nm, in the meantime the reagents (BPR + EV) exhibited maximum absorption at 640 nm. The apparent molar absorptivity of the complex is ε535= 1.70×105L·mol-1. cm-1. If the dual peak-dual wavelength method is used for the determination, the sensitivity of the method will be doubled., Δε535~640= 3.20×105 L·mol-1·cm-1. Beer's law is obeyed for the molybdenum concentration 0~0.16μg/mL. The Sandell's sensitivity is 0.00057μg/cm2. Reaction is highly selective. The common metal ions do not interfere with molybdenum reaction except germanium, titanium and tungsten ions
    The Simultaneous Determination of Germanium, Molybdenum, Tungsten and Tin in Multicomponent System by Applying Modified Factor Analysis-Photometry
    He Xiwen, Ren Hongji, Shi Huiming
    1988, 9(9):  902-906. 
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    This paper describes the modified factor analysis approach which is based on the concepts of nonzero-intercept and simulated pure component curve can be used to simultaneously determine complicated system. The color reaction of p-nitro-phenylfluorone and cationic surfactant (CTMAB) with germanium, molybdenum, tungsten and tin has been investigated. The optimum condition for the simultaneous determination of the four elements is discussed. Satisfactory results can be got for steel samples as well as synthetic samples by applying our present method.
    The Syntheses, Properties and Electronic Structure of the Eight-Membered Ring Explosives Containing N-NO and Gem-dinitro Groups
    Chen Boren, Xiao Heming, Li Yongfu
    1988, 9(9):  907-911. 
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    This paper describes the syntheses of three new eight- membered ring explosives containing N-NOand gem-nitro groups. Some of their properties such as the impact sensitivity and thermal stability and others have been investigated. The electronic structures have been calculated by quantum chemical CNDO/2 method. It is shown that if the N-NO2 group in these molecules is substituted by N-NOgroup, then the impact sensitivity of these explosives will obviously become lower. The C-Nbond gem-dinitro group for each eight-membered ring explosives is probably the initiation bond of the thermal decomposition because the bond order of the C-Nbond in gem-dinitro group is the lowest, and the corresponding bond energy of ℃-Nbond is the lowest, the C-Nbond in gem-nitro group is comparatively weak.
    The Synthesis of Ethyl Cephalotaxinyl Oxalate and Its Application in the Synthesis of Cephalotaxus Ester Alkaloids
    Liu Xingping, Wang Yongkeng, Li Shaobai, Pan Xinfu, Li Yulin, Huang Wenkui
    1988, 9(9):  912-914. 
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    In this wrok, ethyl cephalotaxinyl oxalate was prepared by ester exchange and the synthesis of the key intermediate, α-keto-acetyl-cephalotaxine, was achieved by treating this oxalate with a Grignard reagent. This constitutes an efficient modification of previously reported mathods for the synthesis of cephalotaxus este ralkaloids.
    Synthesis, Structures and Conformational Analysis of p-Tolylethynyl Fe-S Complexes (μ-p-CH3C6H4C=CS) (μ-RS)Fe2(CO)6
    Song Licheng, Wang Zhongxia, Wang Jitao
    1988, 9(9):  915-920. 
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    It has been found that alkynyl Grignard reagent p-CH3C6H4C=CMgBr cleaves the S-Sbond of μ-S2Fe2(CO)6 to give an "open" type of intermediates (μ-p-CH3C6H4C=CS)(μ-XMgS)Fe2(CO)6. The intermediates further react with various organic halides to yield eleven new "open" Fe-Sclusters with the general formula (μ-p-CH3C6H4C=CS)(μ-RS)Fe2(CO)6. The structures of all the complexes were characterized by IR, 1H NMR, 13CNMRand elemental analysis. According to chemical shifts and integrated values of related signals of 1H NMRthe possible isomers and the isomer ratios of some clusters have been determined.
    Monte-Carlo Algorithm for Computer Simulation of Homogeneous Chemical Reaction Systems
    Liang Yizeng, Yu Ruqin
    1988, 9(9):  921-925. 
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    The computer simulationt of homogeneous chemical reaction systems including oscillating reaction systems has been investigated in terms of the collision theory of reaction rate and the principle of independence of coexisting chemical reaction. In a systematic discussion of the Monte-Carlo simulation problem,emphasis was given to the connection between the branching reaction in simulation and the number of available collisions, as well as the connection between the computer time and real reaction time. Asimple algorithm applicable to simulation of various kinds of homogeneous chemical reactions has been worked out, and was successfully used for the investigation of mechanism of chemically oscillating reactions.
    Relation of SiO2/Al2O3 Ratio to Crystal Lattice Parameter and Framework Vibration Frequencies
    Jiang Dazhen, Lu Huijuan, Tang Fengjie, Jiao Qingzhe, Liu Xiaoxun
    1988, 9(9):  926-930. 
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    X-ray powder diffraction has been applied to study ultrastable fau-jasites prepared by treating HYwith SiCl4 at high temperature. Aplot of the crystal lattice paramer of USYagainst the number of Al atoms per unit cell shows distinct break at crystal lattice parameter near 24.45 to 24.55. Two equations have been got to calculate the SiO2/Al2O3 ratio of USYframework from crystal lattice parameters.The infrared spectrum in the region 400 to 1500cm-1 is a sensitive tool indicating structural features of zeolite frameworks. The plots of several frequencies against -crystal lattice parameters and atoms fraction of Al also show distinct breaks. When a crystal lattice parameter is small than 24.41, bands are split about 460 and 1145cm-1. The peaks tend to be sharp with decrease in crystal lattice parameter.
    A Study of Methanol Adsorption on Si-Fe Zeolite
    Yu Youlu, Ding Yingru
    1988, 9(9):  931-934. 
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    By means of temperature-programmed desorption-mass spectroscopy(TPD-MS), infrared spectroscopy (IR).Mossbauer spectroscopy (MBS), methanol (CH3OH) adsorption on Si-Fe zeolite was studied. It was found that CH3OH can be adsorpted not only on Br(φ)sted acidic centres, but also on the surface basic centres. The acidic sites were cooperated with the basic sites in methanol adsorption. However, CH3OH did not be adsorpted by Fe atoms. Amodel of methanol adsorption on the Si-Fe zeolite was proposed in this paper.
    Ab imtio and CI Studies on the Photolysis of Methyl Nitrite
    Yu Jianguo, Liu Ruozhuang
    1988, 9(9):  935-940. 
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    The photolysis of methyl nitrite has been theoretically studied. The ab initio and MP2 calculations with STO-3Gbasis set show that both the S0 and T1 states of trans-CH3ONO are more stable than the corresponding states of its cis-isomer. With the same method, the bond dissociation energies of the ground state,first excited (n→π*) and second excited states (n→π*) of CH3ONO, withrupture of the bond between Nand Oatoms to producing CH2O·and·NO radicals, are calculated to be 238.14, 68.99 and -183.97 kJ/mol, respectively, which supports the experimental fact that methyl nitrite is easy to proceed the photodecomposition. The photoelimination of the CH3ONO (to produce CH,Oand HNOmolecules) is also investigated by ab inition and CIcalculations. The relationship of energies among S0, T1, S1, T2 and S2 states along reaction path shows that the reaction rate of the photoelimination could not be fast, this is also in accord with the low quantum yield measured experimentally.
    13C NMR Studies on the Monomer Reactivity Ratios of Various Species in Anionic Styrene-Butadiene Gopolymerization
    Yu Kesi, Ying Shengkang, Yu Huaigen
    1988, 9(9):  941-944. 
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    By using the 13CNMR experimental data, the monomer reactivity ratios of various reactive species in the n-BuLi-THFinitiated butadienestyrene copolymeriza-tion system were evaluated. The results are in good agreement with the data obtained from the kinetic studies. Markobium mechanism of this anionic polymerization is discussed. Furthermore, the diad composition of copolymer at high conversion have been explored by integration.
    Synthesis of Several Polymer-Supported N-Pd Complex Catalysts and Their Catalytic Activity for the Hydrogenation of 1,5,9-Cyclododecatriene
    He Binglin, Sun Juntan, Wang Li
    1988, 9(9):  945-950. 
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    Many polymer-supported palladium complex catalysts were prepared.The selective hydrogenation of 1,5,9-cyclododecatriene .with polymeric N-Pd complexes in 1:1 benzene-ethanol at 100℃ and 20 kg/cm2 was investigated. The relation-ships between the N-substituted groups and the active centre from the catalysts were examined.It was found that the catalysts containing chelating ligands displayed high activity for selective hydrogenation.
    Studies oh Complexes of Quadrivalent Cerium with Tetraphenylporphin and Its Derivative
    Wang Jingqiu, Zhang Congliang, Qin Zibin
    1988, 9(9):  951-953. 
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    The synthesis and the characterization of the metalloporphyrin complexes of the acetylacetonate, cerium(Ⅳ) with tetraphenylporphin (A) and tetra-p-chlorophenylporphin (B) have been described for the purpose of the study on inter-ation of cerium (Ⅳ) cation with both ligands acetylacetone (acac) and porphyrin. These compounds have been identified by elemental analyses, electron, infrared, Laser Raman and 1H NMRspectra. The results indicated: the Ce(Ⅳ)-Ostreching vibrations in the infrared spectra of Ce(acac)4 exhibits an absorption peak at 398cm-1. The chemical shifts of its protons (Hd and He) in 1H NMRspectra show 1.92 and 5.28 ppm, respectively. But in the porphyrin complexes of Ce (Ⅳ) ,they are shifted to high magnetic field for the enhanced shielding effect. The Ce(Ⅳ)-Ostreching frequency in the Laser Raman spectra of the tetra-p-chlorophenylporphin of Ce(Ⅳ) appears in 372cm-1.The stoichiometric ratio of the porphyrin complexes of Ce(Ⅳ) is 1:1:2 (Ce (Ⅳ):A(B): acac) similar to that of the thorium porphyrin complex.
    Studies on Rare Earth Metal-Hydroboron Compounds(Ⅸ)——Synthesis of N,N'-Bis(Salicylidene)-1,3-Propyiendiamine Complexes of Lanthanide Decahydrodecaborates
    Hu Peizhi, Zhang Lun, Liu Xiyan, Tan Zhongjia, Zhang Guomin
    1988, 9(9):  954-956. 
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    The lanthanide complexes of N,N' -bis(salicylidene)-1,3-propylendiamine (salpr) containing decahydrodecaboric anion have been obtained by the ligand synthesis and templet synthesis. The complexes which Lave the general formula [Ln(salpr)3]2(B10H10)3(Ln = La,Nd,Cd,Ho and Lu) were examined by elemental analyses, IRspectra and 1H NMR. The thermal stabilities of these complexes were investigated by DTA. In addition, the influence of different solvents for the two tautomeric forms of salpr has been studied by 1H NMR.
    Hydrogen Diffusion in Amorphous MmNi4.5 Mn0.5 Film
    Chao Jinlan, Zhou Zuoxiang, Wang Chunming, Jia Yuqun, He Lanling
    1988, 9(9):  957-959. 
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    The MmNi4.5Mn0.5 (Mm. misch rare earth elements) thin film was prepared by conventional vacuum deposition technique. MmNi4.5Mn0.5 powder was placed on tantalum boat which was preheated at a temperature of;1400℃.All the component of MmNi4.5Mn0.5 evaporated immediately at this temperature and was deposited onto a cleaned palladium film (0.040mm) which was-placed just: above the tantalum boat. Analysis of the film was performed by means of X-ray fluorescence spectroscopy and it was confirmed that the composition was MmNi4.5Mn0.5. It was shown by X-ray diffraction spectroscopy that the MmNi4.5 Mn0.5 film was amorph-cus alloys.The diffusion coefficient of hydrogen in the film at ambient temperature has been studied with electrpchmical technique. The diffusion coefficient Dof hydrogen in amorphous MmNi4.5Mn0.5 alloy film was determined, the value of Dis (2.46±0.36)×10-7cm2/s.
    The Polarographic Behavior of Cu(Ⅱ)-Ethylene-Diamine System and Determination of Stability Constants in Presence of Deficient Ligand
    Yu Huaqiang, Zhou Bensheng
    1988, 9(9):  960-962. 
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    The polarographic curve of Cu(Ⅱ)-ethylenediamine (En)system is divided into two or three waves when CEn/CCu<2. The 1st wave corresponds to Cu2+ +2e+Hg→Cu(Hg); the 2nd, 2CuEn2++2e+Hg→Cu(Hg)+CuEn22+ ; the 3rd,CuEn2++2e+Hg→Cu(Hg)+En and CuEn22+2e+Hg→Cu(Hg)+2En. The possibility of determining both of the stability constants of CuEn2+ and CuEn22+ , β1 and β2, polarographically in presence of deficient ligand is discussed.
    An Investigation in Separation of the Geometric Isomers of Alkyl Aryl Ketone Oxime by TLC
    Long Yunxian, Ye Chunzhi, Huang Runqiu
    1988, 9(9):  963-965. 
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    The TLC separation of the geometric isomers of alkyl aryl ketone oximes which are the intermediates in the synthesis of a new group of pyrethroidlike alkylaryl ketone oxime o-ethers (the general structure is <这里有图片19880921-963-1.gif> ) has been investigated. The optimal conditions and the results for the E/Z separation of six different substituted phenyl isopropyl ketone oximes are given. The dependence of the three thin layer chromatographic parameters, Rf, ΔRf and α, on varying ratio of the TLCmobile phase ha been studied and the effect of the activity of absorbent on the separation is discussed.
    Preface
    Synthesis of Arylpyruvic Acids
    Hu Hongwen, Feng Xianqi
    1988, 9(9):  966-968. 
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    Arylpyruvic acids were prepared in good yields by the reaction of aryldiazonium salts with 2-substituted acrylic acids,,NHCHO,OCH3 or PO(OCH3)2), in the presence of cupric chloride.
    Articles
    Study on the Reaction of Dehydroacetic acid with Ammonia
    Chen Weixing, Feng Juncai, Fu Heliang, Sha Jian, Zhang Lin
    1988, 9(9):  969-971. 
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    In this work, the reaction of dehydroacetic acid (1) with aqueous ammoniahas been further studied by means of HPLC. In this reaction lutidone (2), lutidonecarboxylic acid (4) and 2,6-dimethyl-4-aminopyridine (6) have been separated or prepared.DHA-imide (3) (3-iminoethyl-4-hydroxy-6-methyl-2-pyrone) is the intermediate which gives various compounds under different conditions. The mechanism of this reaction is discussed.The structures of compounds have beeen characterized by IR, 1HNMR and MSspectra.
    Surface Acidity and Catalytic Activities of Zeolite CF-2
    Chen Xiangxiong, Li Quanhua, Gao Zi
    1988, 9(9):  972-975. 
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    CF-2 is a novel type of highly siliceous zeolite first synthesized in laboratory from glycerine-Na2O-SiO2-Al2O3-H2O system with structure similar our to Theta-1, ISI-1, KZ-2, Nu-10 and ZSM-22. The surface acidity and catalytic activities of CF-2 zeolites with different SiO2/Al2O3 ratios have been studied. TPDresults suggest that there are two types of acid sites on CF-2. In comparison to HZSM-5, CF-2 zeolites have less acid sites and lower acid strengths. CF2 zeolites, especially the sample with low SiO2/Al2O3 ratio, show catalytic activities towards cumene and n-hexane cracking, xylene isomerization and met-hanol conversion reactions. Unlike HZSM-5, CF-2 zeolite favours dimethylether and aliphatics over aromatics in the methanol conversion reaction.
    Studies on the Determination of Trace Selenium (Ⅳ) by the Multiple Semidifferential Cathodic Stripping Voltammetry
    Zhou Shuping, Dong Venju
    1988, 9(9):  976-978. 
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    This paper describehe the determination of Se(Ⅳ) in 0.5 mol/L HCl-4μg/mL Cu(Ⅱ) solution by title metthod. The height of the strpping peak can be deter-mined at -0.54 or -0.63 V (vs. SCE), determined concentration range is 0.04- 20ng/mLof Se, and the pre-electrolytic potential, is -0.25 or -0.35 V. The detection limit is pg/mLlevel. The relative standard deviation is 7.1% at the concentration of Se(Ⅳ) 0.14 ng/mL.The reaction process and behavior of the cathodic stripping peaks have been studied and discussed.
    A Method of Controlling the Structre of Active Core During Preparing Star Polymer
    Yin Rui, Shen Jiacong
    1988, 9(9):  979-981. 
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    In the synthesis of gelation star polymer, the size of gelation core and the number of active site (namely branch) are the key to determine the structure of star polymer. This paper presents a method of effective controlling the structure of active core.