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Table of Content

    24 August 1981, Volume 2 Issue 3
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    Articles
    STUDY OF THE MECHANISM OF CHELATE AND SYNERGISTIC EXTRACTION OF Pb++, Ni++, Mn++, Co++, Cd++, Ca++, Mg++ AND La+++ IONS WITH PYRAZOLONE-TBP-BENZENE
    Li Le-min, Hsu Kwang-hsien
    1981, 2(3):  265-274. 
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    The mechanism of chelate and synergistic extraction of Pb++,Ni++,Mn++,Co++ Cd+++,Ca++, Mg++ and La+++ ions with l-phenyl-3-methyl-4-benzoyl-pyrazolone-5(HPZL)-benzene and HPZL-TBP-benzene solution were investigated by the two-phase titration method. The composition of the extracted chelates and synergistic complexes and their stability constants have been determined. The experimental results showed that for the metal ions which are extracted strongly the synergistic effects are weaker, while the metal ions extracted weakly exhibit stronger synergistic effect. It was also found that there exist some relation between the coordination number and the cova-lent character of the coordinate bond. If the coordinate bond has more cova-lent character, the coordination number tends to take the smaller value and the synergistic effect is weaker. On the other hand, if the coordinate bond has more ionic character, the coordination number tends to take the larger value and the synergistic effect is stronger.
    SOLVENT EXTRACTION MECHANISM OF Ni++、Co++、Cu++ WITH DI-2-ETHYIHEXYLPHOSPHORIC ACID BY THE TWO-PHASE TITRATION METHOD
    Wang Wenqing, Mou Xiru
    1981, 2(3):  275-284. 
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    A Two-phase Titration Method has been used tor the investigation of solvent extraction mechanism of Ni++、 Co++and Cu++with Di-2-ethylhexyl-phosphoric acid. The method is very simple and rapid. In the experiment we only want to determine the variation of pH, and calculate the extraction constant. In the ranee of concentration studied, metal ion (Mi++、 Co++ and Cu++) is extracted into the organic phase by HDEHP-C6 H6 system with the formation of MA2·2HA.
    A STUDY OF MECHANISM OF ZINC DEPOSITION IN Zn2+-HEDP-CO32- SYSTEM OF ELECTROPLATING-Ⅰ-COMPOSITION OF THE MIXED COMPLEX AND ACTION OF CO32-
    Fang Jingli, Ma Sinmao, Lu Weizhen
    1981, 2(3):  285-293. 
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    1-Hydroxyethylidenediphosphonic acid (HEDP, HSL) has been used in zinc plating, but no information of its mechanism of deposition has been reported. The composition of the mixed complex in plating solution was determined by chemical analysis,IR spectra and conductometric titration.The results showed that the composition corresponded to K6[Zn(HL) (CO3)2].Effects of the second ligand CO32-on electrochemical behavior of plating solution has been investigated. The results indicate that the CO32-has an important action on stability of the plating solution, dissolution of anode, polarization of cathode and throwing and covering power of solution.Effect of the form of mixed complexes on electrodeposition has been discussed. Restriction of application in determining electrodeposited complex ion on cathode by method of exchange current density has also been discussed.
    DETERMINATION OF THE DEGREE OF ATOMIZATION IN AIR-ACETYLENE FLAME USING RELATIVE PEAK ABSORPTION TECHNIQUE
    Zheng Yansheng
    1981, 2(3):  294-300. 
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    In this article the relative peak absorption technique for the determination of degree of atomization in air-acetylene flame was proposed and its theoretical basis was disccussed as well.The degree of atomization of Na, Mg,Cr and Mo in air-acetylene flame was measured with Cu as a reference element. The effect of the flame composition and height on absorbance for four elements and the degree of atomization of Na and Mg were investigated. It was shown that both of these two factors can influence the degree of atomization, but the influence of flame composition is larger than that of its height. Therefore, the degree of atomization is a relative value which varies with the condition of measurement.
    STUDIES ON THE CONSTANT-POTENTIAL CHRONOAMPEROMETRY IN THE CASE OF LAMINA FLOW
    Zhang Rongkun, Luo Yinghua
    1981, 2(3):  301-308. 
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    The chronoamperometry at constant-potential under the condition of lamina flow has been suggested. The method is to measure the electrolytic current and time of the solution when its state changes from flow to stagnation and to calculate the coulomb. The electrolytic potential is controlled at the position of the polarographic limiting-current. The electrolytic cell is made small and thin in size and contains three electrodes: a Ag/AgCl for reference electrode,a gold ring for auxiliary electrode and a gold dish for indicator electrode.An equation that relates coulombs and concentrations of the solution has been given. The principle of quantitative analysis and experimental operations has also been described in the present paper. After the interference caused by capacity currect and unstability of the electrode were eliminated, the sensitivity of the method increased to the extent of 10-7M. It has been proved experimentally that this method has several advantages, such as low noise, high resoluting power, stableness and good repro-ducibility. The advantages of stripping analysis were also shown obviouslywhen combined with chronoamperometry.
    COMPUTER-ASSISTED STRUCTURAL ELUCIDATION CONSTRAINED GENERATION OF ACYCLIC ISQMERS
    Zhu Siyu, Zhang Jinpei
    1981, 2(3):  309-316. 
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    A program LYCT which can generate an exhaustive, nonredundant list of all the acyclic structural isomers of a given empirical formula has been completed. It can also prune these isomers by means of feeding the program with “BADLIST” and “GOODLIST”. The numbers of isomers of some compounds resulted from LYCT are however, inconsistent with previous data[1.9], The differences are discussed to demonstrate the validity of this program. An example illustrating the use of LYCT is presented.
    TLC DETECTION OF VOLATILE NITROSAMINE NI GRAIN WITH TWICE DEVELOPMENT ILGHT-DECOMPOSED METHOD
    Wei Tianjun, Feng Guangying
    1981, 2(3):  317-320. 
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    In this paper, the difference in photochemistry properties between nitrosamine and pigments is investigated. The TLC method of twice developing light-decomposition is presented to detect the volatile nitrosamines in grain.First, nitrosamine and pigments are developed within a certain distance and, after that, the nitrosamine is decomposed under irradiation with ultraviolet light. When they are developed for the second time, the pigments keep going up and are being completely separated from nitrosamine.
    STUDIES ON ANALYSIS OF ORGANO-METALLIC COMPOUNDS-Ⅰ-MICRODETERMINATION IN ORGANO-METALLIC COMPOUNDS OF CARBON AND HYDROGEN
    Wei Tao, Huang Dianqun, Chen Yaozu
    1981, 2(3):  321-326. 
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    In this paper, a micromethod for the determination of carbon and hydrogen in organo-metallic compounds has been reported, 3-5 mg of sample was covered with 10 mg of freshly prepared Co3O4 in platinum boat and burned over a catalyst of products of thermal decomposition of silver permanganate under a current of oxygen (25ml/min. ) at 500-550°C. The combustion took about 10 minutes. The data of determination of a series of standard organo-metallic compounds showed that the absolute deviation of this method was within ±0.3%. As a result of low combustion temperature, the duration of the silica combustion tubes was much increased. The properties of MnO2 reagents for absorbing nitrogen oxides prepared by various methods were compared and the procedure for preparing the most effective reagent was described.
    PREPARATION OF MERCURY ION-SELECTIVE ELECTRODE AND ITS APPLICATION IN MICROANALYSIS OF ORGANIC MERCURY
    Wang Changyi
    1981, 2(3):  327-331. 
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    This method combines the oxygen flask method with the mercury ISE for microanalysis of organic mercury compounds. This method has the advantages of being simple and rapid with sharp end-point and absolute error 7.3%. The presence of N, F, S, P, B, Si, K and Na does not interfere with the mercury determination.
    ACTIVITY COEFFICIENTS OF SOME MONOMER-MONOMER AND MONOMER-DIMER
    Zheng Guokang, Chen Mingzhi
    1981, 2(3):  332-336. 
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    The activity coefficients of benzene in infinitely dilute solution in fourteen solvents at 60°C have been evaluated by gas-liquid chromatography. The activity coefficients of the same systems have been calculated by means of a monomer-dimer solution model. Calculation showed that the experimental data could be predicated by this model.The activity coefficients of toluene, ethylbenzene, o-xylene, rn-xylene and p-xylene in infinitely dilute solution in four solvents at 60°C have been evaluated also by gas-liquid chromatography.By applying a monomer-monomer solution model, the solubility para-menters of these solvents have been calculated. The values of solubility paramenter for the same solvent with different solutes are constant within the experimental uncertainty,
    THE ANODIC DISSOLUTION AND PASSIVATION MECHANISM OF Zn IN KOH AQUEOUS SOLUTIONS
    M. K. Ye, J. Q. Wang, C. W. Tian
    1981, 2(3):  337-350. 
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    The anodic dissolution and passivation process of Zn in KOH aqueous solutions under 30° C and-20°C is studied by the methods of rotating disk electrode, steady polarization curve, AC impedance and galvanostatic chr-onocoulometry.
    A STUDY OF NICKEL BORIDE AS ANODE CATALYST FOR ALKALINE FUEL CELLS
    Zou Yunhong, Cha Quansin, Kao Rong, Wang Lifeng
    1981, 2(3):  351-357. 
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    Nickel boride catalyst is prepared by the reaction of KBH4 with Ni(Ⅱ) salt. Nickel boride samples prepared by different methods of after-treatment were characterized by chemical analysis, differential thermal analysis, X-ray diffraction and electrochemical tests. Experimental results indicated that catalyst samples of widely different boron content were oxidized almost at the same potential. However, in order to get more active catalyst for waterproofed electrode, the atomic ratio Ni/B of catalyst should be carefully controlled. It does not mean that the Ni/B ratio of the catalyst should be controlled at certain fixed value. We would only like to emphasize that, in order to get better results, the method of catalyst processing should be in accordance with the method of electrode fabrication. In other words, the optimal Ni/B ratio depends on the method of electrode fabrication. Some fuel cell anodes with nickel boride catalyst have been already running contineously at 50ma/cm2 for more than 3000 hours without serious deterioration.
    THE COMPLETE ANALYSIS OF THE SPECTRUM OF RUBY
    Yang Zhongzhi, Wang Zhizhong, Tang Aoqing
    1981, 2(3):  358-364. 
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    In this paper we have carried out theoretical calculation on the energy levels of ruby by means of theoretical methods of the field theory[1]. In the calculations we have considered all electrostatic interactions, octahedral-field potential and trigonal-field potential and spin-orbital coupling interaction of the d3 configuration. The calculated energy levels and splittings coincide better with experimental values. In this paper we have also discussed effects of various parameters on energy levels and splittings.
    A STUDY OF THE ACTIVATION MECHANISM IN THE COPOLYMERIZATION OF ETHYLENE AND PROPYLENE WITH THE ADDITION OF ACTIVATORS
    Yang Shilin, Feng Linxian, Zhu Qinqin, Qi Gourong, Zheng Wen
    1981, 2(3):  365-371. 
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    In the copolymerization of ethylene and propylene, the catalytic efficiency of the Ziegler-Natta type V-Al catalyst system might be enhanced by adding some organic compounds as activators. With the addition of p-toluene sulphonyl chloride (TS), azobenzene (AB) and tetrahydrofuran (THF) as activators, the catalytic efficiencies of the V-Al catalyst system in both EPM and EPDM copolymerizations were raised and the amounts of vanadium compound used as main catalyst were reduced. Among these three activators, AB is most remakable. Catalytic efficiency of AB enhancements of up to 10 times as exhibited by the V-Al system alone were observed. The corresponding efficiency enhancements of TS and THF were 3-6 times and 1-2 times, respectively.The activation mechanisms of the polymerization mith the. addition of the activators were rarely reported except for the addition of trichloroa-cetate as activator. In the present paper, the activation mechanism is discussed in detail, the different effects of the added activators on the yields of the polymerization and the kinetic behaviour of the polymerization were studied. The reactions of these activators with the components of the V-Al catalyst system were also investigated. According to their modes of acti-vation, these activators could be divided into two groups. For TS and AB, the catalytic efficiency was improved through the regeneration of the deactivated centers by the oxidation of V2+ to V3+ , while for THF, through the prolongation of the life time of the active centers by the coordination with THF.
    A STUDY OF MAGNETIC FIELDS TO STEREOCHEMICAL CONFIGURATION INFLUENCE OF POLYMERS-Ⅰ-POLYMETHYLMETHACR YLATE
    Zhou Chaohua, Su Zhixing
    1981, 2(3):  372-376. 
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    Polymerization of methyl methacrylate in magnetic fields influences the syndiotacticity in the molecular chain of polymethylmethacrylate. By increase of magnetic field intensity, the percent content of the syndiotactic of polymethylmethacrylate increases, and so does glass temperature.The composition probability of N chain segments of the syndiotactic of polymethylmethacrylate in the molecular chain of polymethylmethacrylate can also be calculated.
    THE INHIBITION OF THE GAMMA RADIOLYSIS OF THE 732 POLYSTYRENE SULFONIC ACID RESIN BY SOME TYPICAL SOLUTES AND THEIR INTERFACE KINETICS
    Wu Jilan, Zhang Yuhua
    1981, 2(3):  377-384. 
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    The protective actions of concentrated solution of X-1, Ac- , NO3-1, and C2H5OH on the γ-radiolysis of the 732 polystyrene sulfonic acid resin have been studied. All of these solutions can inhibit the y radiolysis of the polystyrene sulfonic acid resin. In neutral medium, the abilities of the solutes to inhibit the y radiolysis of the resin are given by the order: NO3-1>C2H5OH>Ac-1>Cl-1, Br-1>I-1The protective effect of the halide ion depends strongly on the pH of the solution (see Fig.2).
    STUDY OF EFFECT OF NONIONIC SURFACTANTS MICELLES ON COLOR REACTIONS-Ⅰ SPECTROPHOTOMETRIC STUDY OF N12+-PAN-TRITON X-100 SYSTEM
    Qi Wenbing
    1981, 2(3):  385-388. 
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    The complexation reaction between niekel(Ⅱ ) and 1-(2-pyridylazo)-2-naphthol (PAN) in the presence of Triton X-100 micelles has been investigated spectrophotometrically by comparison with the results obtained from chloroform extraction method and “cloud point” phase separation method. The characteristic results obtained from these methods are quite agreeable. It is deduced that the Triton X-100 micellar phase plays the same role as the organic solvents for liguid-liguid extraction. However the micellar phase is pseudo-phase and may be regarded as pseudo-phase extraction.On the basis of spectrophotomctric, cloud point and solubility studies, it may be supposed that the phenolic hydroxy group of PAN is bound with the ether oxygen of the oxyethylene group by hydrogen bonding or forming complex with it.The Ni2+-PAN complex and hydrophobic portion of PAN molecule are incorporated into the hydrocarbon interior of the micelle.In the presence of Triton X-100 micelles the apparent stability constant of Ni2+-PAN is larger (K'stab is 5.3×l09 and that of solvent extract Ni2+-PAN system is 2.1×109). But the reaction is not sensitized.
    A NEW COLORIMETRIC INVESTIGATION IN THE DETERMINATION OF TWO INTERFERING COMPONENT SYSTEMS-THE GRAPHICAL RATIO METHOD
    Shih Huiming, Ho Hsiwen, Yang Wanlong
    1981, 2(3):  389-392. 
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    A new graphical ratio method has been proposed for the determination of two interfering component systems. The theoretical fundament of the method has been discussed. It is advisable to use two component spectro-photometric analysis.
    SPECTROPHOTOMETRIC DETERMINATION OF A SMALL AMOUNT OF ZIRCONIUM BY CHROME AZUROL S (CAS) WITH TRITON X-100
    Jiang Shufu
    1981, 2(3):  393-396. 
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    A method of Spectrophotometric determination of small amounts of zirconium with chrome azurol S (CAS) in the presence of non-ionic surfactants TritonX-100 was investigated. The color of zirconium complex is blue in a pH range from 5.7 to 6.6 at 605 nm and is stable for at least 120 minutes. Beer's law is obeyed up to concentration of 1.25 μ g/ml of zirconium. The molar extinction coefficient of the complex at 605 nm is 3×104 mol-1 cm-1. The complex composition of zirconium to CAS was confirmed to be 2:3 by continuous variation method. A number of ions which interfere with the determination can be masked by the addition of various masking agents.
    SYNTHESIS AND APPLICATION OF THE NEW MACRORETICULAR ADSORBENTS-THE H SERIES OF ADSORPTION RESINS
    Ho Pinglum, Chang Chuansing, Li Xiaobai, See Yungfu, Wang Jianying
    1981, 2(3):  397-399. 
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    The new macroreticular adsorbents-the H series of adsorptionresins have been prepared and have high specific surface area (usually reaching 1000 to 1369m2/g), high porosity, high strength and density.The H series of adsorption resins have widely been used for decoloring, extraction and purification of vitamines, antibiotics, etc.
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