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    24 March 1993, Volume 14 Issue 3
    Articles
    Synthesis of α- and β-Cs4H3[SiW3O37Cr3(H2O)3]·xH2O and Their Catalysis of Epoxidation of Olefin by PhIO
    LIU Jing-Fu, ZHAO Ben-Liang, LI Jin-Chang, XU Gui-Ying, ZHU Zhi-Ping
    1993, 14(3):  297-300. 
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    The synthesis of α- and β-Cs<H3[SiW9O37Cr3(H2O)3] β xH2Oand their catalysis for epoxi-dation of olefin are reported.The heteropolyacid salts have an ability to catalyze the epoxidation of olefin by PhIO, and the catalytic activity of them is probably related to the fact that the substituted Cr ( Ⅲ ) can be oxidized to a higher oxidation state and the compound with a higher oxidation state has an oxidation property.
    Synthesis and Characterization of N-Salicylideneamino Acid Zinc(Ⅱ) Complexes
    LI Zhi-Chang, LI Tai-Shan
    1993, 14(3):  301-304. 
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    Five complexes of N-salicylideneamino acid zinc ( Ⅱ ) were synthesized.The structure of the complexes were characterized by elementary analysis, thermogravimetric and differential thermal analysis, molar conductance, infrared, electronic and fluorescence spectra.The five complexes have the composition of Zn[(Sal-Gly)·H2O], Zn[(Sal-DL-Val)·H2O], Zn[(Sal-L-IIe) H2O], Zn[(Sal-L-Leu)·H2O] and Zn[(Sal-L-Phe)·H2O] respectively.The results of the studies indicate that the tautomeric equilibrium between the " enol-imine" and "keto-enam-ine" exists in the Schiff bases derived from salicylaldehyde with amino acids.The structures of zinc ( Ⅱ ) complexes must be those indicated by formula Ⅲ and Ⅳ.The molar conductance data show that they are nonelectrolyte, and the TG-DTAresults show that the decomposition temperature of complexes is above 300℃ and the thermal stability of them is higher than that of the ligand.Fluorescence intensity of zinc( Ⅱ ) complexes in alcohol is 43-227 times as high as that of the Schiff bases at excitation wavelength (λex = 368 nm) and emission wavelength (λem = 444 nm) of the complexes.N-salicylideneamino acids can be used in fluorescence analysis.
    Crystal Structure and Fluorescent Spectra of Eu(DBM)3(2,2'-bipy) Complex
    WANG Ming-Zhao, JIN Lin-Pei, LIU Shi-Xiong, CAI Guan-Liang, HUANG Jin-Ling, QIN Wei-Ping, HUANG Shi-Hua
    1993, 14(3):  305-309. 
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    Eu(C15H12O2)3(C10H8N2), M=1103.03, belongs to monoclinic system with space group P21/c, α=l.3309(4) nm, b=2.2473(5) nm, c= 1.6231(1) nm, β=109.68(1)°, K=4.571 (2) nm3, Z=4, Dx= 1.43 g·cm-3, λ(MoKα) = 0.071069 nm, μ=14.24 cm-1, F(000) = 2004, T=295K.The structure was solved by heavy-atom method and refined by full-matrix least-squares technique for 64 non-hydrogen atoms anisotropically for 5590 reflections with I>3σ(I).The final Ris 0.046.The metal atom in the monomeric molecule is coordinated by six Oatoms of DBMligands and two Natoms of 2,2' -bipy to form a distorted square antiprism.Eu( Ⅲ ) ion as luminescent probe features a high sensitivity and easily interpretable spectra by the selective laser excitation.High resolution laser excitation and emission spectra were recorded at 77K.An unique peak at 17237 cm-1 indicating only one Eu( Ⅲ ) ion site in the title complex was observed.Spectra of 6Do7Fj(J= 0-2) transitions show that the symmetry for Eu( Ⅲ ) site is C1 which is in agreement with the result of crystal structure determination.
    Synthesis and Crystal Structure of [Et4N)1.5{Li(H2O)6}0.5] [Cd2(SC6H4But-4)6]·EtOH
    TANG Ka-Luo, LI Ai-Qun, JIN Xiang-Lin, TANG You-Qi
    1993, 14(3):  310-313. 
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    The title complex was synthesized and structurally characterized.The crystal belongs to the space group C2/c, α= 5.727(3) nm, 6= 1.2059(3) nm, c=2.5245(16) nm, β=101.39(5)°, V = 17.0921(5) nm3, Dc=l.178 g/cm, Z=8, R=0.076 for 4692 unique reflections [F≥4.0σ (F)].The cadmium is tetrahedral coordination with two terminal and two bridging ligands.The central M2S2 ring is planar and approximately rectangular.
    Studies on the Luminescene of Eu3+-doped Lanthanum Phosphate
    ZHOU Ji, SU Mian-Zeng
    1993, 14(3):  314-316. 
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    Emission spectrum of Eu3+-doped lanthanum phosphate consists of strong emission of Eu3+ 5Do7F1transitions and weak emission of Eu3+5Do7F1transitions.The main peak of 583 nm is originated from 5Do7F1 transition.According to the Eu-concentration dependence of the emission intensity and fluorescence life-time of these two types of transition, the mechanism of cross-relaxation and energy transfer between Eu3+ions have been investigated.
    Synthesis of Manganese (Ⅱ) Complexes and Simulation for Superoxide Dismutase
    MEI Guang-Quan, WANG Lu-Yun, LUO Qin-Hui
    1993, 14(3):  317-319. 
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    We synthesized two macrocyclic and one noncyclic manganese ( Ⅱ ) complexes for simulating Mn-superoxide dismutase(SOD).They were characterized by several physical methods and their structures were identified.Among the three complexes the macrocyclic mononuclear complex has a higher SODactivity than that of the manganese ( Ⅱ ) complexes of carboxylates which were considered as being good model compounds of Mn-SOD.The relationship between the SODactivity and structure of the complexes was discussed.
    Adsorptive Stripping Voltammetry of p-Fluoro-( 4-Diphenylmethylpiperazino- l-yl)-Butyrophenone
    GUO Xu-Ming, HU Nai-Fei, LIN Shu-Chang
    1993, 14(3):  320-323. 
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    In a supporting electrolyte containing NH3-NH4Cl, a reduction peak of p-fluoro-(4-diphenylmethylpiperazino-l-yl)-butyrophenone (FDB) was found by linear-sweep voltammetry at Hg electrode.The peak shows a potential of - 1.43 V(vs.Ag/AgCl) and adsorptive characteristics.The peak current was proved to be contributed by the reduction of both surface species of FDBadsorbed at Hg electrode and solution species of FDBdiffusing to the electrode.When the concentration of FDBis sufficiently low, the sweep rate is sufficiently small and the accumulation time is sufficiently long, the peak current is totally contributed by the reduction of adsorbed FDB.The adsorbed species is most probably neutral molecule of FDB.The saturated adsorption amount of FDBat Hg electrode is 7.04 × 10-11 mol/cm2 and every FDBmolecule occupies 2.34 nm2.The transfer coefficient a of the irreversible adsorptive system of FDBis 0.64.The detection limit of the adsorptive stripping voltammetry of FDBis 5.0 × 10-10 mol/Lwhen the accumulation time is 300 s under an optimized condition.
    Studies on Simultaneous Determination of Trace p-Terphenyl and tn-Terphenyl by Derivative Solid Substrate Room Temperature Phosphorimetry
    DONG Oman, LIU Chang-Song, FENG Ke-Cong
    1993, 14(3):  324-327. 
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    Usually, there is a broad excitation and emission band in room temperature phosphorescence spectra.When a multicomponent mixture is analysed, spectral overlap occurs frequently.Therefore, it is difficult to determine the constituents in mixture.The room temperature phosphorescence characteristics of p-terphenyl(p-TP) and m-terphenyl(m-TP) are extremely similar.The spectral interference between them is very serious.To eliminate this interference, we have set up the second derivative solid substrate room temperature phosphorimetry for the simultaneous determination of trace p-TPand m-TP.The proposed method is simple, rapid and reproducible.Its major advantage is that the mutual interference of p-TPand m-TPcan be eliminated effectively without any preliminary separation.The excitation wavelength of the sample spot was at 288 nm, m-TPwas measured at 448 nm with a positive signal and 460 nm with a negative signal.The calibration curve is linear over the range of 0.46 to 46 ng.The absolute LODis 0.11 ng per spot.The presence of p-TPdoes not interfere with the determination.p-TPwas measured at 526 nm with a positive signal and 548 nm with a negative signal, with a linear range of 0.46 to 46 ng and the absolute LODof 0.07 ng per spot.The presence of m-TPdoes not interfere with the determination.
    Separation and Identification of DABTH-Amino Acids by Reverse-Phase High-Performance Liquid Chromatography
    YIN Chang-Chuan, HUANG Wei-Da, SUN Chong-Rong
    1993, 14(3):  328-331. 
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    Twenty standard DABTH-amino acids were separated and identified on a reverse-phase high-performance liquid chromatography(RP-HPLC) column with isocratic elution at a sensitivity of picomoles.By using the manual DABTH/PITCdouble-coupling method, we have analyzed and identified the N-terminal amino acid sequence of chicken lysozyme.This technique has been verified to be valuable for protein microsequencing at a level of nanomoles.
    Studies on Electrocatalysis of Biomolecules at Modified Electrodes ( Ⅲ )——Catalytic Reduction of Hemoglobin at Chemically Modified Carbon Paste Electrode Containing Cresyl Fast Violet
    HAN Ji-Lin, JING Wei, CHEN Hong-Yuan
    1993, 14(3):  332-333. 
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    Hemoglobin exhibits such a slow rate of electron transfer that no useful current is observed at conventional electrodes, even with the application of relatively large overpotentials, for reasons ascribed to its extented three-dimensional structure and the resulting in accessibility of the electroactive center or to its adsorption onto and subsequent passivation of the electrode surface.Only a few papers dealing with the hemoglobin redox behaviour at solid electrodes have been reported.In the present work, the carbon paste electrode modified with a new mediator cresyl fast violet shows an electro-catalytic activity to the reduction of hemoglobin.In the medium of 0.2 mol/L NaOAc-HOAc (pH = 5.5), the oxidation and reduction peak potentials of the CMEare Epa= - 0.14 Vand Epc=- 0.28 V (vs.SCE), respectively.The CMEshows a good stability and a good current response for hemoglobin.
    Derivative Variable-Angle Synchronous Fluorescence Spectroscopy for Simultaneous Determination of 1-Naphthol and 2-Naphthol
    LI Yao-Qun, HUANG Xian-Zhi, XU Jin-Gou, CHEN Guo-Zhen
    1993, 14(3):  334-335. 
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    Derivative variable-angle synchronous fluorescence spectroscopy is developed to improve the selectivity of fluorescence measurement.The second derivative variable-angle synchronous scanning permits the rapid simultaneous determination of 1-naphthol and 2-naphthol in a mixture from a single spectrum based on a single scan, whereas twice scanning procedure should be required using second derivative constant-wavelength synchronous fluorescence spectroscopy and the quantitative analysis of 1-naphthol in a mixture could not be performed with direct variable-angle synchronous fluorescence spectroscopy.6.7-2000 ng/mL 1-naphthol and 3.6-500 ng/mL 2-naphthol can be quantified with relative standard deviations of l.3%-2.6%.
    Studies on Prussian Blue Modified Electrode by Quartz Crystal Microbalance
    HU Qiang, HU Ji-Ming, HU Yi, LIU Jun-Tang, CHEN Ouan-Quan
    1993, 14(3):  336-338. 
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    Afilm of Prussian blue (PB) was electrochemically deposited on a quartz crystal microbal-ance (QCM).The forming of the PBfilm was monitored in situ by the frequency shift of QCM, the PBfilm is an electroactive polymer film, during reduction of the film and subsequent reoxidation to PB, cation transport in and out of the film.This changes the total mass of the polymer film and alters the frequency of the QCM.From the frequency changes of the QCM, we found that K+, Na+, NH4+ can migrate in and out of the film easily, but it is difficult for Ca2+ to entet the film.
    A Study of the Fluorescence System of Tetracycline-Eu-TOPO-Sodium Dodecyl Sulfonate System and the Determination for Tetracycline
    YANG Jing-He, ZOU Hua-Bin, JIE Nian-Qin, GE Hong-Mei
    1993, 14(3):  339-341. 
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    The Eu-tetracycline-TOPO-sodium dodecyl sulfonate system was studied.Experiments showed that the maximum fluorescence intensity was obtained in the pHrange 7.5-8.7 and when the concentration of Eu3+, TOPOand sodium dodecyl sulfonate were 1.0× 10-5 mol/L, 1.0 × 10-3 mol/Land 1.0× 10-3 mol/L, respectively.This fluorescence system can be used for the determination of tetracycline in serum and urine.The linear dynamic range is 2.0× 10-8 mol/L-1.0×10-5 mol/Lfor tetracycline.The detection limit is 1.2× 10-8 mol/L.The composition of the tetracycline (TC)-Eu-TOPO-sodium dodecyl sulfonate (SDS) complex was examined by using slope-ratio, mole-ratio and continuous change methods.The experiments showed that the ion association complex [Eu(TC) (TOPO)m]+ (SDS)- was formed in the system.The luminescence of complex belonged to M*→Mluminescence mechanism.The fluorescence enhancement is due to the formation of the ion association complex and the micelles.
    Determination of Se by Complexing and Extraction of o-Phenylenediamine-Se Under Ultrasonic Wave
    ZHOU Jian-Bo, ZHANG Qiu-Ping, LIU An-Xi, HU Rong-Ji
    1993, 14(3):  342-344. 
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    This paper reports that under ultrasonic wave complexing and extraction of Se-o-phenylene-diamine were finished simultaneously.With the aid of determination of ABSof toluene extracting liquid, the content of Se was determined.The best condition was the action of ultrasonic wave on the sample for 20-35 min.The average recovery was 98.2-98.3%.The pHrange was 1.7--1.9.
    Synthesis and Herbicidal Activity of Thiophenesulfonylureas Containing Pyrimidines
    XUE Si-Jia, WAN Shu-Qing, LIU Zhao-Jie
    1993, 14(3):  345-348. 
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    Fifteen N'-(4, 6-disubstituted pyrimidin-2-ly)-2-thiophenesulfonylureas were synthesized from thiophene in 4 steps.Eleven of them are new compounds.Their structures were proved by 1H NMR, IR, MSand elementary analysis.Their herbicidal activities have been determined.It is found that some of them show a good herbicidal activity.
    Syntheses, Structure and SAR Study on Sulfonylurea Compounds( Ⅱ )——Crystal and Molecular Structure of N-[2-(4-methyl)pyrimdinyl]-2-ethyl carboxylate-benzene sulfonyiurea
    LI Zheng-Ming, JIA Guo-Feng, WANG Ling-Xiu, LAI Cheng-Ming, WANG Hong-Gen, WANG Ru-Ji
    1993, 14(3):  349-352. 
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    Synthesis and crystal structure of title molecule was reported here.This crystal consists of title molecules with solvent molecules CH2C12. It is triclinic, belonging to space group P1 with unit cell parameter a=0.7413(2) nm, 6=0.9166(5) nm, c= 1.6289(5) nm, α=75.97(4)°, β=82.28 (2)° γ=76.22(3)° V=l.039 nm3, Z=2, R=0.067 for 1914 reflections.Molecular structure was discussed.There are three different planes in the molecule, in each of which a conjugated system was formed.The intra-molecule and inter-molecule hydrogen bonds between atoms Nand Hhave been found.
    The Chemistry of α-Oxo Ketene Cyclic Dithioacetals(Ⅳ)——Studies on the Dehydration of Adducts of β,β-1,3-Propylene-dithio-α,β-Unsaturated Arylketones with Allyl Grignard Reagents
    LIU Qun, DONG De-Wen, YANG Zhi-Yun, HU Yu-Lan, JING Feng-Ying, XIAO Yan-Wen
    1993, 14(3):  353-357. 
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    Anew route for the synthesis of dialkylthio conjugated alkenes (3) has been developed.The addition of β,β-l,3-propylenedithio-α,β-unsaturated arylketones (1) with allyl or benzyl Grig-nard reagents afforded the carbinols (2).The carbinols (2) were converted to the alkenes (3) via dehydration catalyzed by BF3·Et2O.The course of addition of benzyl Grignard reagents to (1) proceeds by regiospecific 1,2-pattern other than the sequential 1,4-, 1,2-addition, which might result from the hindrance of the rigid cyclic dithioalkyl group in (1), the mechanism and reaction condition are discussed.Thirteen new compounds are prepared, their structure are assigned by 1H NMR, IRand UV.
    Preparation and Evaluation of an Encapsulated Polymer HPLC Stationary Phase
    ZUO Yu-Min, ZHU Bo-Ru, LIAO Yun, GUI Ming-De
    1993, 14(3):  358-359. 
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    Areversed phase stationary phase of HPLCmade by covering a porous copolymer of ethyl-styrene with divinylbenzene on the surface of silica gel is reported.The encapsulated polymer packing material maintains the main advantages of both polymer and silica based material.it is not only chemically stable, ion-free, and not soluble in solvents, but also of high rigidity, and has compatibility for solvent changing from organic to aqueous and reverse.Such packing is easy to pack and has a high column efficiency.Its application to the separation of aniline derivatives is documented.
    A Study of Porphyrin Compounds(XX)——Studies on Synthesis and Photoelectrochemical Properties of 5-(p-Hexadecyloxyphenyl)-10,15,20-triphenylporphyrin and 5-(p-Hexadecanoyloxyphenyl)-10,15,20-triphenylporphyrin
    LI Ping-Ying, GAO Cui-Qin, CHENG Guo-E, HUANG Su-Qiu
    1993, 14(3):  360-362. 
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    The reactions of hexadecyl bromide and palmitoyl chloride with 5-(p-hydroxyphenyl)-10, 15,20-triphenylporphyrin( Ⅰ ) gave 5-(p-hexadecyloxyphenyl)-10,15,20-triphenylporphyrin( Ⅱ ) and 5-(p-hexadecanoyloxyphenyl)-10, 15, 20-triphenylporphyrin ( Ⅲ ), respectively.Elementary analysis, NMR, IRand Vis spectra of the two new compounds are presented.( Ⅱ ) and ( Ⅲ ) are photosensitive and have some properties analogous to p-type semi-conductor.The photovoltage and pho-tocurrent response will reach to maximum within15 s.
    Studies on the Absolute Configurations of Two 10-hydroxy-9-oxo-Furoeremophilanes Using CD Spectra
    CHENG Dong-Liang, GAO Jian-Jun, NIU Jin-Kui, TIAN Xuan
    1993, 14(3):  363-365. 
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    Because of the absence of hydrogen in position 10, it is difficult to determine the C-10 configurations of 9-oxo-furoeremophilanes using1H NMRspectra.By means of CDspectra, absolute configurations of two new furoeremophilanes were established.Some aspects about CDspectra of 10-hydroxy-9-oxo-furoeremophilanes were discussed.
    A Study of Iridoid Glycosides from Pedicularis Alaschanta
    GAO Jian-Jun, JIA Zhong-Jian, LIU Zi-Min
    1993, 14(3):  366-367. 
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    Anew iridoid glycoside, 10-O-acetylaucubin, was isolated from the ethanolic extract of Pedicularis alaschania along with aucubin.The structures were established by means of spectral and chemical evidences.
    Isopiestic Osmotic Coefficients and Activity Coefficients of Sodium Benzenesulfonates
    WU Ding-Quan, ZHAO Ji-Hong, HU Chao-Zhen, QU Song-Sheng
    1993, 14(3):  368-371. 
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    The osmotic coefficients and activity coefficients of sodium benzenesulfonate, sodium beivenesulfinate, sodium p-aminobenzenesulfonate, sodium p-hydroxybenzenesulfonate and sodium m-nitrobenzenesulfonate in aqueous solution have been determined at 298.15 Kby the isopiestic method.The excess molar Gibbs free energies were calculated from the osmotic and activity coefficients.
    One-electron Properties of Pyridine, Benzene, Pyrazine, Pyrrole, and Imidazole
    WANG Yi, SUN Jia-Zhong
    1993, 14(3):  372-377. 
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    The one-electron properties- (a) the second moments of the molecular charge distribution <x2>, <y2>, and <z2> ; (b) the charge density distribution about the atomic nuclei δ; (c) the expection value <r-1>; (d) the dipole moment μ; (e) quadrupole moment θ, of pyridine, benzene, pyrazine, pyrrole, and imidazole are recalculated with the one-electron wave functions of the improved SCF-Xα-SWmethod.The Charge-Partitioning Approximation of Case et al.has been used in the calculation.Some improvements in the calculational results, relative to the original SCF-Xα-SWmethod, have been obtained.
    Studies on Ionic Conductivity of [(PbCl2)0.55(PbO)0.45]1-x(KCl)x Systems
    ZHENG Wen-Jun, YANG Ping-Hua, MENG Guang-Yao
    1993, 14(3):  378-381. 
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    As one of the most promising ionic conducting system for application, PbCl2-PbOwas studied on the modification with doping potassium chloride.It was found that a little amount of KC1 could make the sample be directly sintered in air.The samples with nominal composition of [(PbCl2)0.55 (PbO)0.45](1-x)(KCl)x(z=0-0.30) were measured by ACcomplex impedance technique, Wagner DCpolarization and potentiometric methods.X-ray diagram indicated the main phase in the highly conducting system.For the samples within the composition range of 0.05<x<0.22, the lowest value of conductivity was observed, and the role of mixed grain boundaries was used to account for this phenomenon.
    An Application of UNIFAC Equation to H2O-n-C12H26-D2EHPA-LaCl3-HCl Extraction System
    CHEN Jian, CONG Wei, LI Zong-Cheng, LI Yi-Gui
    1993, 14(3):  382-387. 
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    The liquid-liquid equilibrium data for H2O-n-C12H26-D2EHPA-LaCl3-HCl extraction system were determined.The partial pressures of n-C12H26 in LLEfor H2O-n-C12H26-D2EHPAwere measured by gas chromatography with hydrogen flame detector.The Pitzer equation is used to calculate the activity of water and the individual ionic activity coefficients of H+ and La3+ in aqueous phase.The U-NIFACequation is used to calculate the activity coefficients of components in organic phase.Amethod to divide the extractant and metal organic complex into functional groups is proposed.By regression of the experimental data, the equilibrium constant of the extraction reaction and the UNIFACgroup interaction parameters were obtained, which can be used in the whole concentration range.The equilibrium concentration of lathanum in this system can be calculated successfully.
    Studies on the Inhibition and Catalysis Effects of Tetren in Zinc Electrodeposition
    CAI Jia-Le, ZHOU Shao-Min
    1993, 14(3):  388-391. 
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    The inhibition and catalysis effects of tetren on discharge of Zn(OH)42- in alkaline zincate bath have been studied by means of voltammetry and differential capacity measurement.The results show that tetren has a higher adsorptivity on Hg-electrode/solution interface.The adsorption quantity is increased and the potential range of adsorption is extended toward more negative potential with increasing of tetren concentration.It is found that tetren inhibits the discharge of Zn(OH)42- at potentialbetween -1.3——1.45 V.At the potential more negative than - 1.45 V, two catalytic currentpeaks are observed on voltammetric curves, and they are merged into a peak as the concentration of tetren increased.As tetren concentration is higher than5× 10-3 mol/L, the peak current is directly proportional to the concentration of tetren and ZnOboth, but inversely proportional to NaOHconcentration.The relevant empirical formula are given in this paper, and the catalysis effect of tetren on Zn(OH)42- dischage is discussed by homogeneous parallel reaction and the ion pairing effect.
    Adsorption and Surface Reaction of Ethylbenzene over Ferrosilicate with FeZSM-5 Structure
    KAN Qiu-Bin, WU Zhi-Yun, YU Ji-Hong, PENG Shao-Yi, XU Yi-De, XIONG Guo-Xing, HUANG Jia-Sheng
    1993, 14(3):  392-396. 
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    XPS, ESRand Mossbauer techniques were used to investigate the adsorption of ethylbenzene over FeZSM-5 zeolite catalyst.Astronger interaction between ethylbenzene and framework iron of FeZSM-5 is found, which results in a 0.7 eVchemical shift of Fe2, binding energy towards a low value.Ethylbenzene molecule acting as a ligand could coordinate with the framework iron with coordination unsaturation to form a chemical bond.The study on the temperature programmed desorption and the surface reaction of ethylbenzene over FeZSM-5 further characterizes the catalytic active centers for ethylbenzene reactions.
    T-P-X Relationship of the Water-Acetonitrile Mixtures Containing Salt
    LIU Wen-Bin, WANG Jian-Ji, WANG Cai-Lan, LU Jin-Suo
    1993, 14(3):  397-401. 
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    The T-P-Xdata of water-acetonitrile-(KCl, CaCl2, KI) system, at 26.66-93.33 kPa and in the salt concentration range of 0.1-0.7 mol·kg-1, were measured by using the CP Iebul-liometer.The Clausius-Clapeyron-type equation of binary mixtures containing salt was derived by using the thermodynamical theory.Under the particular condition, this equation may be reduced to several formula presented in literatures.The theoretical equation was proved to be correct by the experimental results.It has been shown from the thermodynamical theory and the experimental results that: (1) The relation between Pand Tis satisfied with the Clausius-Clapeyron-type equation, when the concentration of the salt and the relative composition of the acetonitrile aqueous solutions are fixed.In other words, plotted IgPagainst 1/T, a series of straight lines can be obtained.(2) When the relative composition of binary solution and the pressure of the system are fixed, the boiling point of the systems is decreased by the addition of KCIand CaCl2, and the extent of decrease of CaCl2 is larger than that of KCI.However, under the same condition, the boiling point of the systems is increased by the addition of KI.(3) For each of the salts, the change tendency is increased with the increase of the concentration of acetonitrile in the water-acetonitrile mixtures.The reason for the unusual phenomena of the decrease of boiling point may be attributed to the difference of interactions between salt-water and salt-acetonitrile in the salted binary systems.The effect of salt on the properties of binary systems depends on the net result of interaction between the salts and the mixed solvents.
    Kinetics of Thermal Isomerization of meso-Diethyl 2,3-Dicyano-2,3-Diphenyl Succinate and the EPR Spectra of the Intermediate in Melten State
    QI Chen-Ze, JIA Zhi-Sheng, YANG Di-Lun
    1993, 14(3):  402-405. 
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    The kinetics were studied for the thermal isomerization of meso-diethyl 2,3-dicyano-2,3-di (p-Xsubstituted phenyl) succinates (X = H) in melten state and the EPRspectra of the intermediates (X = OCH3, CH3, H, Cl, NO2) were observed.The central carbon-carbon bond of the five isomers was homolysed to give ethyl α-cyano-α-ethoxycarbonyl-p-substituted benzyl radicals.The structures of the intermediates were determined by compute simulation.The kinetic results indicate that the equilibrium constant Kreduced as the rise of the reaction temperature.The active parameters were found to be ΔHdl-meao= - 18.02 kJ/mol, ΔSdl-meao= - 26.51 J/mol·K, ΔH = 151.78 kJ/mol, ΔS = 71.64 J/mol·K.dl-Isomer is more stable than the corresponding meso-iscmer.
    The Physico-Chemical Properties of Saponified Extractants
    LI Gai-Ling, PENG Qi-Xiu, GAO Hong-Cheng
    1993, 14(3):  406-409. 
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    Since the end of 70's, the formation of reversed micellar and microemulsion in extracted organic phase has been studied in our laboratory.We have known that the acidic extractants saponified by alkaline solutions or alkali metals have the similar structure and properties to surfactants, and can form reversed micellar or water-in-oil microemulsion in organic phases during the extraction.Herein we report the changes of the physico-chemical properties conductivity, density, index of refraction and viscosity, of a saponified extractant system in different volume fractions of water added with P507 as the extractant, Na and Kas the saponifier, sec-octyl alcohol as the cosurfactant, and n-heptane as the oil.The density and index of refraction as the function of Φw are shown in Fig.1.The variations of conductivity and viscosity of organic phase during the adding water to P507K-ROH-heptane system are shown in Fig.2-Fig.6.It can be seen that the density, conductivity and viscosity increase and the index of refraction decreases with the water content in the microemulsion.It can be seen that the results are helpful to understanding the nature of the extraction mechanism and kinetics.
    Kinetic Study on Hydration Reaction of Dichlorotetraaquochromium ( Ⅲ ) Chloride
    LIU Cheng-Dong, CHEN Bao-Ji, LI Wen-Hua
    1993, 14(3):  410-412. 
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    The kinetics and mechanism of hydration reaction for the hydrated isomer of chromium ( Ⅲ ) chloride, dichlorotetraaquochromium( Ⅲ ) chloride were investigated and the order of the reaction has been determined by spectrophotometry.The kinetics of hydration reaction of the hydrated isomer of chromium( Ⅲ ) chloride shows that the synthesis of [Cr(H2O)5Cl]Cl2 will be more difficult.
    Preparation of Vanadium Trioxide from Hydrazine-Containing Vanadium Salt by Thermal Decomposition
    WU Jie-Da, LIU Hui-Zhong, ZHU Sheng-Xiang, MA Zhen-Dong, ZHOU Yu-Lei
    1993, 14(3):  413-414. 
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    Anew method for preparing V2O3 by decomposing hydrazine-eontaining vanadium salt thermally was described.The hydrazine-containing vanadium salt is synthesized by the reaction between ammonium metavanadate and hydrazine in an oxalic acid medium, and under an atmosphere of nitrogen V2O3 can be prepared from the hydrazine-containing vanadium salt by the thermal decomposition.It shows that V2O3 has magnetism and electrical conductivity.
    Preparation of 4-Methylcyclohexanone by Catalytic Hydrogenation of p-Cresol at Normal Pressure
    SHI Xian-Fa, JIANG Zhong-Liang, XLA Qing
    1993, 14(3):  415-416. 
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    4-Methylcyclohexanone was prepared by the catalytic hydrogenation of p-cresol at normal pressure over Rh on 3.17 mm alumina pellets as the catalyst.The conditions for the catalytic hydrogenation were also studied.The preheated temperature of p-cresol was chosen as 160°C.The rate of flow of hydrogen was selected to be 144 L/h.The mixture ratio of the reacting gas was hydrogen i p-cresol=15 : 1 (molar ratio).When the catalytic temperature was 60,80,100,120,140,160,180, 200, 220℃, the conversion rate of p-cresol was found in 0.1, 33.3, 33.S, 18, 3,12.7,1.0, 0.2, 0.2, 0.5%, respectively.
    The Morphology Study of Latex Particles of Sty rene-Acrylate Copolymer Containing Acrylic Acid
    LIU Feng-Qi, LIU Zheng-Ping, LI Zhi-Ying, TANG Xin-Yi
    1993, 14(3):  417-420. 
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    The morphology of latex particles of acrylic acid/butyl acrylate/styrene copolymer emulsion have been examined by transmission electron microscopy (TEM).The effect of copolymer composition, flexible segment and acidity adjusted with aqueous ammonia of the systems on the morphology of latex particles has been discussed.The morphology of soft latex particles was observed successfully by TEMafter using phosphotungstic acid (PTA) served as support and a negative stain.In an usual condition, the state of film-forming copolymer existence was supposed.
    A Kinetic Analysis of Radiation Cross-linking and Scission of Polymers
    ZHANG Yi-Qun, JIN Dan-Liang, CHEN Xin-Fang, TANG Ao-Qing
    1993, 14(3):  421-423. 
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    The result of the analysis on the kinetics of cross-linking and scission of polymers subjected to irradiation states that the cross-linking is not directly proportional to the dose, especially in the early stage of irradiation.So a rapid drop of molecular weight should be observed at the small dose.This is demonstrated by the result of [η] of irradiated polymethylene terephthalates.
    Effect of Organic Solvents on the Molecular Folding and the Enzyme Activity of Fruit Bromelain
    CHEN Qing-Xi, YAN Si-Xu
    1993, 14(3):  424-427. 
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    Changes of the molecular folding of fruit bromelain perturbed by methanol, ethanol and ethylene glycol have been studied by means of measuring the fluorescence spectra, differential UV-ab-sorbed spectra and circular dichroism spectra.The fluorescence intensity of the enzyme increased distinctly with increasing organic solvent concentrations, suggesting that the microenvironments of aromatic amino acids have distinctly changed.The differential UV-absorbed spectra showed that there were two positive peaks at 232 nm and 288 nm, both of them intensified with increasing concentrations of organic solvents.The 232 nm peak is in concordance with the change of the folding of the enzyme molecules, while the 285 nm peak is in concordance with the change of the microenvironments of tyrosine and tryptophan residues.The circular dichroism spectra showed that the natural enzyme has two negative peaks at 208 nm and 225 nm.These negative peaks of the enzyme perturbed by methanol and ethanol intensified obviously, but in the presence of ethylene glycol, the 225 nm peak increased, while the 208 nm peak decreased and red-shifted in position, eventually the peak disappeared completely at a concentration of 50% of ethylene glycol, indicating that the enzyme molecule has extended completely.
    Emulsifier-free Emulsion Polymerization Participated by KPS-CuSO4-Na2SO3
    DAI Li-Zong, ZOU You-Si, CHEN Shi-Qun, PAN Rong-Hua
    1993, 14(3):  428-431. 
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    Rapid emulsifier-free emulsion polymerization of methyl methacrylate-styrene was discussed in the presence of redox initiator KPS-CuSO<-Na2SO3. When [MMA]=0.51 mol/L, [St] = 0.49 mol/L, temp.70℃, more suitable quantity of redox initiator was obtained: [KPS]=2.77× 10-3 mol/L, [CuSO4]=l.50×10-5 mol/L, [Na2SO3]=2.77×10-3 mol/L.Reaction time was 100 min.Under the conditions as indicates above, the conversion of monomers surpassed 90%.Restrictive aggregation of emulsion particles existed in the process of reaction.Molecular weight and its distribution of emulsion which were produced by three system of emulsion polymerization are discussed.According to Arrheniu's figuration, the activation energy of polymerization (Ea = 81.6 kJ/mol) was counted.The reaction rate constant kp=321.9 L/mol·s) at 70℃ was calculated.
    Preparation of Polystyrylsulfonyl Chloride Resin and Its Application in Synthesis of Nitrogen-Containing Basic Resins
    HUANG Wen-Qiang, LI Chen-Xi, MEN Ai-Ju, PAN Tong-Tong, HE Bing-Lin
    1993, 14(3):  432-435. 
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    Anew method for preparation of polystyrylsulfonyl chloride resin(l) is described in which the commercially available sulfonated ionic exchange resins (H+ form) were treated in ethanol with pyridine to convert into pyridinium polystyrylsulfonate, the latter was refluxed with thionyl chloride to give resin 1. Anumber of nitrogen-containing basic resins were obtained by the reaction of resin 1 with polyethylenepolyamines, α-aminopyridine, 1,2,4-triazole and 2-aminothiazole, respectively.
    The Polymerization Kinetics of Acrylamide in Glycol Solution Induced by He-Ne Laser with Toluidine Blue as the Sensitizing System
    HE Yi, CHEN Yong-Chao, LIANG Zhao-Xi
    1993, 14(3):  436-439. 
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    The polymerization kinetics of acrylamide(AM) induced by He-Ne laser with toluidine blue (TB)-triethanolamine(TEOA) as the sensitizing system has been investigated in glycol(EG)-H2Osolution and in EGsolution, respectively.The photoredox of TB-TEOAis influenced by the higher viscosity and polarity of EG.The photofading rates of TBdecrease with the raising of [EG].The effect of EGviscosity on the polymerization of AMis also significant.The overall apparent kinetic equation of polymerization in EGsolution and the chain transfer constant for EGhave been determined.The overall apparent activation energy of polymerization in EGis much higher than that in H2Osystem.
    Toughening and Reinforcement of Ductile Polyvinyl Chloride by Rigid Organic Filler
    WU Qi-Ye, YANG Wen-Jun, QIU Yi-Ming
    1993, 14(3):  440-441. 
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    The modifications of ductile polyvinyl chloride (e.g.PVC/CPE, PVC/ABS) with rigid organic fillers (abreviation ROF, e.g.PS, PMMA, SAN) were studied.The results show that filling ROFin small amount to ductile PVCmatrix leads apparent improvement of impact strength while tensile strength and modulus increase slightly.These are different from the traditional elastomer-toughening of plastics in regularity and feature.
    A New Calculation Method for IR Spectra Analysis of Polybutadiene
    ZHANG Zhe-Yan, WANG Dong-Jie, QU Shu-Hua
    1993, 14(3):  442-444. 
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    The microstructure of polybutadiene sample has been determined by factor analysis of IRspectra in the range of 1000-650 cm-1 and the calculation method corrected molecular absorbance.The result was proved more reasonable in comparison with those used in IRspectra analysis.