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    25 January 1982, Volume 3 Issue 1
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    Articles
    THE DISPROPORTIONAL DISSOCIATION EQUILIBRIUM AND DISSOCIATION CONSTANT OF BINUCLEAR MOLYBDENUM (V) DIETHYLDITHIOCARBAMATE
    Bai Mingzhang, Luo Xuanggan, Sun Lijuan
    1982, 3(1):  1-5. 
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    The solution of Mo2O3(S2CNEt2)4 does not obey Beer's law because of disproportional dissociation in to MoO(S2CNEt2)3 and MoO2(S2CNEt2)2. The dissociation constant has been determined spectrophotometrically as 2.2×10-4 at 15℃.The solution of Mo2O8 (S2CNEt2)4 in CH2Cl2 can be oxidized by air to form MoO2(S2CNEt2)2.The solution of MoO(S2CNEt2)2 in CH2Cl2 reacts with oxygen in air to form Mo2O3 (S2CNEt2)4 at first and then to be oxidized further to form MoO2(S2CNEt2)2.
    DETECTION OF COMPLEXATIOM BETWEEN CROWN ETHERS AND RARE EARTH IONS BY CHROMATOGRAPHIC METHOD
    Yang Yansheng, Zhu Jiaqin
    1982, 3(1):  6-12. 
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    The complexation between crown ethers and rare earth ions was detected by paper-chromatographic method and stastic adsorption equilibrium. The effect of counter-anion has also been studied.The crbwn ethers used were: Benzo-15-C-5, Dibenzo-18-C-6, Cylic tetra-mer of tetrahydrofuran and acetone, Benzo-15-C-5-formaldehyde copolymer and Dibenzo-18-C-6-formaldehyde copolymer.The main experimental results obtained are as follows:1. The order of stabity of complexes of various crown ethers with rare earths is: Benzo-15-C-5>Dibenzo-18-C-6>>Cyclic tetramer of tetrahydrofuran and acetone, and Benzo-15-C-5-formaldehyde copolymer>Dibenzo-18-C-6-formaldehyde copolymer.2. The order of stability of complexes of rare earth ions is- Sm3+ > Er3+=La3+ (by paper chromatographic test), and Er3+>Eu3+>La3+ (by method of adsorption equilibrium).3. The order of stability of ion-pairing with counter anions is: picrate> trichloroacetate>sulphonsalysilate>>Cr, NO3-, ClO4- and SO4=.
    THE RECRYSTALLIZATION OF ZEOLITE MOLECULAR SIEVES-RECRYSTALLIZATION MECHANISM OF 4A TO NaY ZEOLITE
    Xu Qinhua, Bao Shulin, Dong Jialu
    1982, 3(1):  13-18. 
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    It is well known that the change of metastable zeolite to a morr stable one depends upon the intrinsic properties of the zeolite and also the chemical environment in which it exists. We studied the probability of transformation of zeolite from one type to another when changing the chemical environment. We investigated respectively the transformation of added zeolite to F, AG4 or Ω type in its own formation environment and also studied the process and mechanism of the transformation of NaAto NaFzeolite in the chemical environment of NaF type formation. Scanning electron microscope, X-ray diffraction and high vacuum adsorption methods were employed in these studies.
    Preface
    STUDIES ON SILICIC ACID AND ITS SALTS (XII)-REACTIONS OF FLUORIDE-ION WITH SILICIC ACID AND THEIR EQUILIBRIUM CONSTANTS
    Chen Rongsan, Liu Haicheng, Wang jinxi, Dai Anbang(Tai An-pang)
    1982, 3(1):  19-27. 
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    Fluoride-ion combines with silicic acid only in acid solution, although it catalyses the polymerization of the silicic acid in neutral and alkaline solution. Fluoride-ion concentrations in silicic acid solution of different concentrations and varied F/SiO2 ratio were measured with fluoride-ion selective electrode. Results of measurements showed that a decrease of [H+] was accompanied by an increase of fluoride concentration in solution, i.e. the amount of fluoride-ion combined with silicic acid decreased. At [H+]<10-5M, there was no combination at all. These findings are in agreement with the mechanism which was proposed previously concerning the effect of fluoride-ion on polymerization of silicic acid,In acid solution, when fluoride concentration is far less than that of silicic acid, the chief species of the latter is Si(OH)4 and that of fluoride is HF and their reaction may be represented as:The for mation constant β1 of the product formed was found to be. β1 = 1.7×103. At high acidity, [Si(OH)8OH2]+ might be formed and its reac tion with HFis given as:When the ratio F/SiO2 was higher, the following reaction took place.Si (OH)4 + 6HF = [SiF6]2- + 2H+ + 4H2O. The gross constant, β6 was found to be: 2×l012.
    Articles
    ION EXCHANGE PROPERTIES OF STANNIC PHOSPHATE (Ⅲ)CHROMATOGRAPHIC BEHAVIOUR OF 44 CATIONS ON STANNIC PHOSPHATE LAYERS
    Ying Bohai, Lei Genhu, Liu Ginying
    1982, 3(1):  28-34. 
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    Thin layers of stannic phosphate have been used to study the chroma-tographic behaviour of 44 metal ion in DMSO-nitric acid systems and DMSO-H2O systems. Binder-free thin layers of stannic phosphate have been prepared. This specific dimethylsulfoxide(DMSO) effect has been explained and used for some binary mixtures separations, and separations such as Hg2+-Pb3+, Cd2+-Pb2+Hg22+-Hg2+, Hg2+-As3+, and Pb2+-Zn2+ have been achieved, Various important separations are listed.
    ESTIMATION OF TRACE SILVER BY CATALYTIC KINETICS
    Chen Guoshu
    1982, 3(1):  35-40. 
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    In this paper, estimation of trace silver(I) by catalytic kinetics of the reaction of silver(I) react with α,α'-dipyridyl and potassium ferro-cyanide was studied. It's showed, such catalytic reaction reacted in zero order, and under the conditions supported in this paper, sensibility of this method was 6.5× 10-4μg/ml and variable coefficient 0.072%. The range of silver estimated was 0-3.5μg/40ml.
    INVESTIGATION OF ANION-EXCHANGE BEHAVIOUR FOR MOLYBDENUM(Ⅵ) AND TUNGSTEN(Ⅵ) IN OXALIC ACID-HYDROCHLORIC ACID SY STEM
    Cai Shulian, Zhou Zhiming
    1982, 3(1):  41-47. 
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    The anion-exchange behaviour of molybdenum (VI), tungsten(VI) and other metal ions on a strong basic anion-exchange resin (Zerolit FF) has been investigated in oxalic acid-hydrochloric :acid system. There are marked differences in adsorptivity for molybdenum(VI) and other metals. The optimum condition for separation is to keep the solution at 0.05Moxalic acid-1.0Mhydrochloric acid. Using a strong basic anion exchange column in the chloride form, tungsten(VI) and other metal ions pass through while molybdenum(VI) is quantitatively retained as oxalate complex.Then molyb-denum(VI) is eluted with 1.0.Mhydrochloric acid. Acolumn 2cm long diameter 0.9 cm is satisfactory for the separation of microgram quantity of molybdenum (VI) from sodium tungstate(reagent grade). The system offers a good method for preparation of tungsten without molybdenum.From the slope of the plot of distribution coefficient against concentration of chloride ion in the system, it has been shown that for molybdenum only one kind of complex ion, MoO3 (C2O4)22-, is predominant and governs the exchange mechanism.
    HPIEC SEPARATION AND DETERMINATION OF CHLORIDE BROMIDE AND IODIDE
    Liu Mancang, Fan Biwei, Hu Zhide
    1982, 3(1):  48-54. 
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    The conditions of HPIECseparation of Cl-, Br- and I- were studied. The ions were separated within 35minutes by using NaNO3 as an eluent. the chloride and bromide contents of.some samples were determined. The trace amounts (ppb order) of chloride in pure water were determined by using a pre-column without a four or six way valve.The IECbecaviouf of Cl-, Br- and I- was interpreted from the theory of hard and soft acids and bases. The following experimental formula was obtained.lgD= 0.24φlg[B]-lg[B] + 0.490 + 0.61 where Dis the distribution coefficient of an anion, [B] is the concentra-tion of the eluent, φ is the softness of the anion as a base.
    STUDIES ON STRUCTURE OF ALL-SOLID STATE FLUORIDE ELECTRODES
    Yu Ruqin, Gong Hongzhong, Chen Benjing
    1982, 3(1):  55-60. 
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    For the construction of an all-solid state fluoride electrode it is necessaryi to find a suitable inner solid state junction between the ion-conducting LaF3membrane and the electron-conducting metalic lead.In order to achleve a good electrode quality, it is essential to get a non-blocking, ohmic contact. Various fluorides and/or metals have been deposited on the LaF3 crystal membrane using' vacuum evaporation method: Bi (A);B1 (B);BiF3-Bi-Ag(B1); Pb(C) ;PbF2-Pb(D);Ag(E);AgF-Ag(F);Au(G);Al(H). The electrochemical properties of the inner junctions have been tested by mea-suring current-voltage characteristics.That the contact obtained is an ohmic one is indicated by linear current-voltage relationship which is independent of the polarity. It has been shown that in systems of direct junction between a metal and LaF3 crystalmembrane the contact resistance shows nonohmic behavior (Fig. 2, A, C, E, G, H). These blocking contacts also possess rectiflying properties.The contact can be made ohmic when a layer of ion-conducting fluoride(BiF3, F2 or AgF) is sandwiched in between the LaF3 crystal membrane and the corresponding metal deposit layer (Bi, Pb or Ag; Fig.2,B,D, F) .The migration of fluoride ions in the LaF3 membrane has been experimentally observed by electrolytic formation of fluorides of bismuth and lead on the LaF3; crystal, membrape surface. The system B1 (BiF3-Bi-Ag) is recommended as especially suitable for the construction of all-solid state fluoride electrodes.The potential resiponse characteristics of the constructed electrodes have been evaluated.
    INVESTIGATIONS ON OSCILLOPOLAROGRAPHIC TITRATIONS (Ⅸ)-Titration of Potassium With Na-TPB
    Pan Sheng-Tian, Kao Hung
    1982, 3(1):  61-66. 
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    In slightly acidic or alkaline solution of acetate, sodium tetraphenyl-borate (Na-TPB) gives a sharp incision on its oscillopolarogram which can be used to indicate the end point of titration Involving Na-TPB. In the determination of K, excess of standard Na-TPB solution is added to precipitate the Kions in alkaline (PH=12) solution and part of the mixture is filtered through dry filter paper and the excess TPBin the filtrate is titrated with T1(I) solution. Divalent and trivalent ions that precipitate in alkaline solution do not interfere with the determination.Pb+2 and Sn+2 ions that distort the oscillopolarogram of TPBcan be masked by EDTA. The method is very simple, accurate and rapid. Thin film Hg electrode is used as a polarized electrode, and the Hg-coated Ag electrode as a depolarized electrode.
    STUDIES ON THE ALTERNATING COPOLYMERIZATION OF BUTADIENE AND PROPYLENE IN THE PRESENCE OF CHLORO-VANADATE-TRIISOBUTYLALUMINIUM CATALYST SYSTEM
    Jiao shuke, Yu Dingsheng, Qi Yincheng
    1982, 3(1):  67-76. 
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    The catalytic activities of various chlorp-vanadates-triispbutylalumin-ium systems in alternating copolymerization of butadiene and propylene have been compared. It was found that the catalyst system consisted of neopentylchlorovanadate-triisobutylaluminium can give .high molecular weight alternating copolymers of butadiene and propylene in high yield.The character and behavior of the alternating copolymerization and the ways for increasing [η] of the copolymer have also been studied.Thus an alternating copolymer of butadiene and propylene .with inherentviscosity 1.7-2.6 dl/g was obtained at -76--45℃, the conversion ofwhich was more than 80%.The resulting copolymers were analyzed by IR and NMR, it was demonstrated that the alternating degree of the copolymers was about 95% and the content of trans-1,4 butadiene unit in the copolymers was above
    Preface
    1H、31P AND 13CNMR SPECTRA OF O-ETHYL-O-ARYL-N-ISOPROPYLAMIDOTHIONOPHOSPHATES
    Zhang Diankun, Li Guowei
    1982, 3(1):  77-82. 
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    The 1H,31P and 13CNMR spectral parameters of O-ethyl-O-afyl-N-isopropylamidothionophosphates have been measured in CDCl3 solutions. It turns out that the 31P chemical, shifts decrease with an increasing of electron-withdrawing abilitya of the para-suhstituents Rin the order, MeO>Me>H>Br>NO2; On the contrary, 1HNMR shifts of phenyl ring (average shifts of A2B3 system) Increase with an increasing of electron-withdrawing ability of the para-substituents R,Viz.MeO<Me<H<Br<NO2; And 13C NMRare without a distinct ofder due to mutual interactions of the two substituents.
    STUDY ON THE REACTIONS OF BIS (DIETHOXYTHIOPHOSPHORYL) POLYSULFIDES WITH SECONDARY AMINES
    Peng Yongbing, Sun Zhiyuan, Bi Guoliang
    1982, 3(1):  83-92. 
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    The present article discussed the reaction of(RO)2(S)n(OR)2(R = CH3, C2H5,n = 2,3,4)with HNR'2(R'=C2H5,is oC2H7).The results of this paper have proved that solid products of the above-mentioned reactions are theammonium salts of the appropriate dithiophosphoric acids: (RO)2S-·H2R'2.In the reaction,all of the S-Sbonds are cleft. The phosphorus--containing polysulfides are not alkylating agents of amines. The course of the reaction can be represented by the following schemes: For example,R,R'=C2H5.
    Articles
    THE CALCULATION OF SOME 1,4-BIS [(SUBSTITUTEDPHENYL )-ETHENYL ] BENZENE DERIVATIVES WITH HMO METHOD
    Xue Jieyou, Lin Shaofan, Zhang Yufan
    1982, 3(1):  93-97. 
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    The charge densities, bond orders, free valences and the energies of n molecular orbitals of some l,4-bis[β-(4-Substituted phenyl) ethenyl] benzene and 1,4-bis [β-( 4-Substituted phenyl ) ethenyl 3-2,5-dimethoxy benzene compounds were calculated with HMOmethod. Arelationship of homologous linearity between the electronic spectra and the energy difference (HOMOand LUMO) is obtained. Besides, it was found that there is a relationship of homologous linearity between the electronic spectra and the absolute values of Hammett' sσp.
    STUDIES ON THE KINETICS OF CARBONATION LEACHING OF VANADIUM-CONTAINING STEEL SLAG
    Ke Jiajun, Li Daowen, Li Ximing, Yue Liangdong, Feng Guangxi, Huang Xiangyu, He Jingqiu, Li Guoliang, Ge Suhua
    1982, 3(1):  98-106. 
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    The kinetics of carbonation leaching of soda-calcined steel slag containing vanadium and rich-calcium as well as a synthetic Ca2V2O7 was studied. The carbonation leaching was done at the temperature range of 15-75℃. The process of carbonation leaching of vanadium from the steel slag is essentially to dissolve calcium vanadate present in the calcined steel slag into the solution in the form of sodium vanadate, and to change calcium into CaCO3 precipitate. This study has shown that when COpasses through the alkaline leaching solution, Na2CO3 is first formed and NaHCO3 consequently, with the decrease of pH. The process of the solid-liquid reaction may be described by a shrinking core model of dissolution of the particle surface. In the initial reaction period the solution leaching of Na2CO3 dominates, but later on that of NaHCO3 prevailes. The rate of the latter was much faster than that of the former, that is, the rate constant of the leaching reaction k2>k1. For the solution leaching of NaHCO3, the equation of the leaching kinetics was obtained,1-(1-a)1/3=kτ[CNaHCO3]0.46 in which a is the fraction of dissolution of vanadium, k is the rate constant of reaction, min-1, τ is the reaction time, min, Cis the concentration of NaHCO3, mol. On th bases of the results of these epxeriments, the mechanism of carbonation leaching of vanadium-containing steel slag has been discussed. This mechanism has also been verified with synthetic Ca2V2O7 sample and an apparent activation energy 25.9 KJ/mol was obtained over the experimental temperature range.
    STUDIES ON ACTIVITY COEFFICIENTS AND SOLVATION NUMBERS OF ELECTROLYTES IN MIXED SOLVENTS-SYSTEMS OF KClO4 METHANOL AND NONELECTROLYTES
    Liu Ruilin, Yang Tan
    1982, 3(1):  107-112. 
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    Solubility data of KClO4 in mixed solvents, namely, methanol-benzene, methanol-toluene, methanol-Carbontetrachloride and methanol-cyclohexane, are reported in this paper, The "free ion" concentrations of KClO4 and KNO3 are calculated by using the association constants given by A,D'Aprano and C. W. Davies[2] of these salts in methanol, The medium activity coefficients fMXexpressed in terms of S0/Sm and (S0)±/(Sm)± are approximately equal and related to rnol fraction XNc of nonelectrolytes in the mixed solvents by the following empirical formula: lgfMX = kXNe where So and Sm are solubilities of salts in methanol and mixed solvensts respectively; the Subscript ± is used for the "free ion" and k is a constant. The formula for the Solvation number of electrolyte n+ +n-=-2lgfMX/lgφp is not valid for KClO4 in these Mixed solvents, where n+ +n- is the sum of the solvation number of positive and negative ion; φp is the volume fraction of methanol in mixed solvents, This result indicates that the solvation layer of ClO4- is not entirely formed by the methanol molecules and the nonelectrolyte exerts some effects on the solvation layer too.experimental data of KNO3, formulas of the solubility and of Solvation numbers are quoted from the former paper of li, Huang and liu[1].
    RESEARCH ON THE POTENTIAL ENERGY BARRIER AT THE ELECTRODEELECTROLYTE INTERFACE
    Zhang Linshao
    1982, 3(1):  113-118. 
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    It is the centre of electrode kinetics that mechanisms of electron transfer through the interface between metal electrode and electrolyte. According to the classical theory of electrochemistry, the electrode process is one that the electron pass over the potential energy barrier of interface to bond with activate ion. However, quantum electrochemistry recognizes also that the electron may tunneles the energy barrier. If we can know the height and width of the barrier when the electrode process occurs, then, in principle we can determine the way of electron transfer, in terms of the calculation method of Schottky emission and "cold emission". However,the height and width of the barrier cannot be measured experimentally as yet, therefore, it is significant to research in to the energy barrier in theory.
    PHOTO ELECTRON SPECTROSCOPY AND THE LINEAR RULE OF THE HOMOLOGOUS ENERGY FACTOR(I)THE HOMOLOGOUS CONJUGATED SYSTEMS
    Sun Yukun, Xu Guangxian, Li Lemin
    1982, 3(1):  119-129. 
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    In the previous papers[4,5], the authors modified the Huckel MOtheory and proposed the Linear Rule of the Homologous Energy Factor, which states that the energies E(n,k) of the molecular orbitals and the physical properties Pof the homologs of different structural types are linear functions of the homologous energy factor X(n,k): E(n,k)=a+bX(n,k) X(n,k)=2l-1/ksinkn/2n+1 P=a'+b'X(n,k) In the present investigation we have collected the vertical ionization data of many homotegous conjugated systems by using UV Photo electron speptroscppy and verified the proposed Rule with satisfactory result. Comparison with Tsiang Min-Chien's Rule of Homologous Linearity was discussed in detail.
    WAVE FUNCTION OF HELIUM ATOM AND HYDROGEN MOLECULE IN MONMENTUM SPACE
    Jikang Zhu, Junqing Li, YuhKang Pan
    1982, 3(1):  130-136. 
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    Wave functions of helium atom and hydrogen molecule in momentum space have been derived. For helium atom, dynamic variables Pr,Pθ, and Pφ,which are conjugated with position variables r,θ, and φ respectively, are used; while for hydrogen molecule, dynamic variables Pζ,Pη, and Pφ, which are conjugated with position variableζ,η, and φ respectively, are used.
    THE PREPARATION OF TUNGSTIC ACID IN WHITE AND POWDERLY FORM
    Gu Yidong(Yih-Tong Ku), Zhu Sisan
    1982, 3(1):  137-140. 
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    It has been shown in previous articles[1,2], that yellow powderly tungstic acid is not merely a metathetical product between a tungstate salt with an acid. Its formation involves a series of consecutive reactions, in which complex tungsten ion is an intermediate form. Improper regulation of conditions[3] will invariably result in admixture of impure white tungstic acid,revealed in its slow dissolution in cold ammonium hydroxide solution, different from the ready solution of the yellow powdery form.When sodium tungstate solution is acidified by dropwise addition of any acid, white tungstic acid will appear due to local reaction. It is curdy in form, and is incapable of being isolated on account of its succeeding reaction with existing tungtates in solution. M. L. Freedman[4] at 1959 was however able to isolate white tungstic acid (C-Phase) in virtually powder form. But Na was still found present in small amount, which indicated the occulation of certain gelatinous form. The yield was also low, only 30%.On recognizing the definite presence of white powderly tungstic acid as a distinct species, and after considering the possible mechanism for its formation, we were enabled to design a procedure for the preparation of pure white powderly tungstic acid in rather high yield. This involves using low acidity, room temperature, an acid with low ability to form complex ion of tungsten, prevention of colloid formation as well as its peptization, and most important of all, the "reversed way of acidification", i.,e., addition of sodium tungstate solution to a dilute acid solution.Filtration and washing were rapid; the filtrate was clear. After washing with pure water, final hashing with ethyl alcol or acetone enabled the removal of adsorbed water, so as to prevent the gradual discoloration of the white powder to faint yellow. The yield after drying at room temperature was 95%.
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