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    24 August 1995, Volume 16 Issue 8
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    Articles
    Luminescence of Eu2+and Mn2+and Their Energy Transfer in SrMgP2O7
    YAO Guang-Qing, ZHANG Liang, SU Mian-Zeng
    1995, 16(8):  1161-1163. 
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    The fluorescence of Eu2+and Mn2+coactivated SrMgP2O7was reported.The emission bands of Eu2+and Mn2+peaking at 400 nm and 670 nm were originated from 5d-4f transition of Eu2+and 4T1(4G)-6Alg(6S) transition of Mn2+,respectively. The dependence of Eu2+and Mn2+luminescence properties on their concentration was investigated.The emission of Mn2+is sensitized by Eu2+and the fluorescence lifetime of Eu 2+is affected by Mn2+.The experimental results indicate that there exists an effective energy transfer from Eu2+to Mn2+in SrMgP2O7host.This energy transfer is due to the electric dipole-quadripole interaction of the resonance transfer.
    Studies on the Synthesis of Dipentyl Phthalate Using Hydrotalcite-Containing Rare Earth as a Catalyst
    LI Lian-Sheng, MA Shu-Jie, HUI Jian-Bin, LIU Xin-Sheng, XU Ru-Ren, BAO Yu-Min
    1995, 16(8):  1164-1167. 
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    Synthesis of dipentyl phthalate using hydrotalcite-containing rare earth as a catalyst is studied in detail,involved influence of amount of the catalyst,mole ratio of phthalic anhydride to n-pentanol,reaction temperature and time on the conversion of phthalic anhydride to dipentyl phthalate. The results show that the catalyst has a high catalytic activity and high selectivity,and the conversion is up to 95%.La content in the catalyst may change in a certain range and the conversion of phthalic anhydride increases with increasing of La content.The surface area of the catalyst calcined at 400℃ is about 120m2/g (BET/N2technique). It has Lewis and Bronsted acid sites and the amount of Lewis acid is far more than that of Bronsted acid.The mole ratio of chemical composition of the catalyst is Mg:Al:La=6:(2-x):x, where 0≤x≤1.0.
    Synthesis and Characterization of α-Dawson Mixed -Valence Tris(tetrabutylammonium) Octadecatungstodiperchlorate
    YUE Bin, ZHU Si-San, XIE Gao-Yang, GU Yi-Dong, LIU Jie, CHEN Min-Qin
    1995, 16(8):  1168-1171. 
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    The title compound has been prepared by dissolving Na2WO4·2H2O in acetic anhydride-DMF-HCl.The blue crystals were obtained upon adding tetrabutylammonium bromide and being recrystallized from DMSO. The results of elementary analysis,IR,CV,ESR,UV-Vis,and single crystal X-ray diffraction indicate that the title compound is aα-Dawson type,one electron reduced "heteropoly-blue" with a central distorted ClO4tetrahedron.
    Studies on Phase Equilibrium of LaCl3·3H2O-18C6-C2H5OH System at 25℃ and Synthesis and Characterization of Solid Coordination Compounds
    LI Qian-Ding, XUE Hong-Fu, REN De-Hou
    1995, 16(8):  1172-1176. 
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    The solubilities of LaCl3·3H2O-18C6-C2H5OH ternary system at 25℃ were investigated by a semimicro method of phase equilibrium study,and the refractive indexes of saturated solutions were determined.The results indicate that there are three kinds of complexes formed in this system,namely,3LaCl3·18C6·9H2O·C2H5OH,2LaCl3·18C6·6H2O·C2H5OH and LaCl3·18C6·3H2O. The behavior of water in this system during the equilibrium was examined and the results show that the mole ratio,H2O/LaCl3,is always 3:1,no matter it is in liquid or solid phase.Three solid complexes were prepared and characterized by IRspectra,DTG,TG and DSC. According to the DSC,the enthalpies of some steps during the decomposition were obtained for these three complexes.
    The Inhibition of FcT on the Biosynthesis of DNA in Ehrlich Ascites Cancer Cells
    GUO Mao-Lin, YANG Pin, ZHAO Chun-Gui, YANG Bin-Sheng, YANG Wei-Ping
    1995, 16(8):  1177-1179. 
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    The effect of FcT[Ferricenium trichloroacetate,bis(trichloroacetic acid)solvate] on the biosynthesis of DNA in EAC cells in vitro was reported in this paper. The experimtal results show that FcT,similar to another anticancer agent titanocene dichloride(TDC),caused a remarkable depression of DNA synthesis activities,and the half-inhibition concentration for FcTis about 1. 0× 10-4mol/L. The irreversible and long-lasting inhibition manner of FcTon DNA biosynthesis indicated that the DNA template was injured by FcT. Meanwhile,the fluorescent quenching of DNA-EB complex by FcT revealed that the DNA duplex might be damaged by FcT.
    Synthesis of Lanthanide Acetylacetonate-meso-tetra-(para-n-pentoxylphenyl)-porphyrin Coordination Compounds
    LI Dong-Mei, LIU Guo-Fa, SHI Tong-Shun, LIN Min, LIU Yu-Wen, ZOU Ming-Zhu, CAO Xi-Zhang, LIU Xiao-Xun
    1995, 16(8):  1180-1181. 
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    In the paper meso-tetra(para-n-pentoxylphenyl)porphyrin T(p-C5H11O)pp and its lanthanide coordination compound LnT(p-C5H11O)ppacac(Ln:Yb,Hacac:acetylacetone) were prepared and characterized by elemental analysis,UV-visible,IRabosorption spectra,X-ray photoelectron spectra,and molar conductance.
    Studies on Indirect Thermo-Optical Detection for Capillary Electrophoresis
    REN Ji-Cun, LI Bin-Cheng, DENG Yan-Zhuo, CHENG Jie-Ke
    1995, 16(8):  1182-1185. 
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    Indirect thermo-optical detection for capillary electrophoresis was presented first by combining indirect detection with thermo-optical method.In this detection,methylene blue solution was used as background electrolyte solution,because it has large molar absorption coefficient at 633 nm. This wavelength matches well with that of He-Ne laser(632.8 nm).The detection was applied to detect amino acids in capillary zone electrophoresis separation. The detection limit for lysine was 5×10-6mol/L(S/N=2).
    Convection-Diffusion Theory of Sample Dispersion in Flow Injection Analysis System
    ZOU Gong-Wei, LIU Zhen
    1995, 16(8):  1186-1190. 
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    Two methods were used to solve the convection-diffusion equation which appropriate to straight single-tube Flow Injection Analysis(FIA)system without chemical reaction,and the concentration distribution of the slug-injected sample after dispersing in the tube was obtained.E-Curve was thereby obtained.Effects of inner radius of tube,length ofreaction tube,length of sampling tube,flow rate and diffusion coefficient on peak shape anddispersion were discussed.The relationship between half peak width and diffusion coefficientwas solved by numerical method.Two methods to determine diffusion coefficient by FIA were suggested.This paper offered a theoretical guideline for design of FIA system,selection of indicator and operating condition.
    Hadamard Tsansform Microscope Image Analysis(Ⅱ)─Study on the Effect of Fluorescence Bleach on Image and Quantitative Data
    MEI Er-Wen, GU Wen-Fang, CHEN Guan-Quan, ZENG Yun-E
    1995, 16(8):  1191-1194. 
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    This paper reports the effect of fluorescence bleach of analytical sample on Hadamard transform image and quantitative data,which was investigated by using a computer simulation method.The instrument of Hadamard transform microscope image analysis was applied to quantitatively analyze the DNA content in plant another dust cell.the result is found satisfactory.
    Studies on Fuzzy Cluster-Factor Analysis Decomposition of the Absorption Spectra of Rare Earth Element Complexes
    WANG Hong-Yan, DU Guo-Hua, WANG Duo-Xi
    1995, 16(8):  1195-1199. 
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    Fuzzy cluster has been applied to factor the analysis spectrophotometry for resolving the optimized problem of calibration model. The precision of calculated concentration has been raised apparently,For realizing the process automation of optimizingcalibration model the data-base has been set and the cluster parameters have been selected.Fifteen rare earth elements in geologic samples have been determined by this method. The relative standard deviation for 15 REEs are 0-3.85%, respectively.
    The Study on the Electrochemical Behaviour of Nile Blue A Modified Carbon Fiber Microcylinder Electrode
    JU Huang-Xian, DONG Ling, CHEN Hong-Yuan
    1995, 16(8):  1200-1203. 
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    The functional group-COOH on carbon fiber microcylinder electrode(CFMCE)was formed by electrochemical oxidation with cyclic voltammetry, and the Nile blue Amodified CFMCE was manufactured by means of electrostatic attraction. The electrochemical behaviour of the modified electrode was studied,and its stability was discussed.The apparent standard electron transfer rate constant and charge transfer coefficient of fixed Nile blue Aat various pH, and the number of H+participating in electrode reaction were determined.The experiments indicated the modified electrode can catalyze the electrode reaction of hemoglobin at carbon fiber microcylinder electrode.
    A Reagentless Alcohol Sensor Based on Thionine-TDI Modified Glassy Carbon Electrode
    YU Ai-Min, HAN Ji-Lin, YANG Ke-Sheng, CHEN Hong-Yuan
    1995, 16(8):  1204-1206. 
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    Alcohol dehydrogenase(ADH) and the oxidized form of nicotinamide adenine dinucleotide(NAD+) were cross-linked directly in aid of the reaction of thionine and toluene diisocyanate(TDI) on the surface of glassy carbon electrode to yield a reagentless alcohol sensor. The NAD+was converted to NADH by oxidation of alcohol catalyzed by ADH and the NADH formed was oxidized electrochemically to the original NAD+by thionine-TDI mediator, thus giving the catalytic current for target analysis. The peak current was linearly related to the concentration of alcohol in the range of 1-15mmol/L. The influence of various experimental conditions was also explored for optimum analytical performance.The sensor remains relatively stable for about 15 days.
    Studies on Uncommon Response for Cu2+by Potentiometry of Carbon Paste Electrode
    HU Xiao-Ya, LENG Zong-Zhou
    1995, 16(8):  1207-1208. 
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    This paper describes a potentiometric method for the determination of Cu2+in 0.1 mol/L HAc-NaAc-0.05 mol/L NaCl buffer(pH5.00)using a carbon paste electrode(without ionophore,mixing paraffin liquid and spectroscopic graphite powder at a ratio of 1.5:1W/ W).The linear range is 2.5 ×10-6～1.0×10-3mol/Lwith 49 mV/decade of calibration slope. It exhibits a high selectivity and a desired reproducibility. The potential response behavior is caused by carbon paste extraction(or adsorption) of the matter being measured and the redox potential mechanism.
    Differential Simple Oscillographic Voltammetry Using Pulse Wave Alternating Current as Polarization Current
    ZHENG Jian-Bin, ZHAO Ming-Ren, ZHU Xiao-Hong, SU Yu-Xiang
    1995, 16(8):  1209-1211. 
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    A new method named differential simple oscillographic voltammetry using pulse wave alternating current as polarization current is presented in this paper,Some advantages of using pulse wave are found.The method of adjusting E～t curve is first proposed in quantitative analysis. The results of determination for a series of drugs show that the method is very useful in actual analysis.
    The Application of an NAD-Silica Biospecific Affinity Chromatography Stationary Phase in Analysis of Nucleotides
    YU Shi-Lin, MIAO Feng-Qin, YANG Zhao-Xia, FENG Ru
    1995, 16(8):  1212-1214. 
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    By using a wide-pore(30 nm),microspheric silica(8μm)as the matrix and γaminopropyltriethoxysilane as the coupling agent,a stationary phase of biospecific affinity chromatography was prepared by chemical binding nicotinamide adenine dinucleotide(NAD) to the γ-aminopropyl modified silica. Using the phosphate buffer(pH=7.0)as a mobile phase,the separation of some nucleotides is accomplished by the detection of UVD(260 nm).The effect of changed ion strengh of eluent on the resolution of nucleotide(AMP, ADP and ATP)has been studied.
    Synthesis of N-Phenylsulfonyl Phosphordiamides and Study on Effects of Structures on Insect Glutamate Potentials
    CHEN Ru-Yu, DAI Qing, WANG Hui-Lin, LIU An-Xi, ZHAO Yong
    1995, 16(8):  1215-1218. 
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    The synthesis of N-phenylsulfonyl phosphordaimides was reported.The effects of the structures of the compounds on the insect glutamate potentials were investigated by using electrophysiological intracellular microelectrode recording technique. The results showed that all of the compounds could block the neuromuscular junctional excitation potentials (EJP),but the blocking time had a great difference. The blocking action could be divided into three types:(1)EJP were blocked progressively;(2)EJP were blocked after a short exciting period;(3)EJP were blocked rapidly. The results of the bioassay showed that the compounds which possessed the second action mechanism had the best killing effect.
    Studies on the Chromatographic Properties of Azacrown Ether Bonded Stationary Phase in Reversed-Phase High-Performance Liquid Chromatography
    DA Shi-Lu, ZHANG Yuan-Wei, WANG Zhong-Hua, QI Guang-Cai
    1995, 16(8):  1219-1223. 
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    This paper reports the complexing capacities for metal ions and chromatographic performances of 3-(aza-18-C-6) propyl bonded stationary phase, which were prepared by solid-liquid phase reaction on the surface of porous silica. Effect of the composition and pH value of the mobile phase,adding metal ion to the mobile phase on the retentions of polar disubstituted benzenes are studies. The chromatographic mechanism is explained.The azacrown ether bonded stationary phase to complexation of metal ion could exhibit various chromatographic properties,dipolar, hydrogen bond,electrostatic and hydrophobic interactions contribute in a certain sense to chromatographic separation,so that the separation selectivity and analytical speed for polar disubstituted benzene derivatives are superior to reversed-phase HPLC with ODS stationary phase.
    Synthesis of 2-Methyl-6-bromobenzotellurazole and Derived Cyanine Dyes
    LUO Xue-Hong, LIU Xiu-Fang, XU Han-Sheng
    1995, 16(8):  1224-1228. 
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    The inner salt 2-acetamido-5-bromophenyl tellurium trichloride was synthesizedfrom p-bromoaniline by mercuration,acetylation and electrophilic substitution of tellurium tetrachloride successively.Reduction of the above salt with sodium borohydride followed by cyclization with concentrated hydrochloride and neutralization with sodium bicarbonate gave the key intermediate 2-methyl-6-bromobenzotellurazole. The latter was alkylated with methyl or ethyl iodide and then condensed with ethyl orthoformate to give two symmetric telluracarbocyanine dyes. The visible absorption of the dyes was also measured.
    Studies on the Synthesis,Structures and Properties of N',N'-Bis(2-chloroethyl)-O-aryl-N3-aryl Thioureido Phosphoramidate
    CHEN Ru-Yu, WANG Hui-Lin, ZHOU Jia
    1995, 16(8):  1229-1232. 
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    In order to look for novel antitumor drugs and virucides with high activity and low toxicity,a series of the title compounds were synthesized by the addition reaction of N,N-bis( 2-chloroethyl)-O-aryl isothiocyanatido phosphoramidate with aryl amine,and their structures were confirmed by spectroscopic and analytical methods. The relationship between the chemical shifts and structures was revealed. The existence of the intermolecular and intramolecular hydrogen-bondings leads to deshielding and to an increase in the frequency of the NMR signal of the hydrogen-bonded protons. Preliminary bioassays indicate that some of them have good inhibitory effects to the growth of different tumor cells such as BGC,HCT,HL60and BCAP cell lines in human bodies and display a high activity against tobacco mosaic virus(TMV).
    The Relationship Between the Intramolecular Hydrogen Bond of Acylthiourea and Its N-Aromatic Substitutents
    WANG Ji-Tao, YUAN Yao-Feng, XU Yu-Ming, YANG Yong-An, WANG Bin, YE Su-Ming
    1995, 16(8):  1233-1236. 
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    The strength of intramolecular hydrogen bond of acyl thiourea can be monitored by the hydrogen chemical shiftδβ-NH. We measured the physical properties of 23 N-ferrocenoyl-N'-aromatic(also alkyl,ferrocenyl) thioureas and 14 N-benzoyl-N'-aromatic thioureas including δβ-NH,pKbin relation with the σ-parameter of substituents on the aromatic ring. We found that there are a good relationship between the strength of the intramolecular hydrogen bondδβ-NH and pKbor σ-parameter of the substituents, thus the substitution effect toword the hydrogen bonding can be revealed.
    The Formation and Performance of Solid Supported Bilayer Lipid Membranes Modified with Crown Ethers
    HE Yu-E, XIE Ming-Gui, ZHAO Yu-Cong, TIEN Xin-Di
    1995, 16(8):  1237-1240. 
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    Self-assembly solid supported bilayer lipid membranes(S-BLMs)modified with crown ethers were formed on metalic wire.The stability and the electrochemical characteristics of the s-BLMs depended on the variety of metalic wire,organic solvent,lipids and molecular structures of crown ethers. The membrane potentials of the s-BLMs prepared with stainless steel wire in mixed solution of squalane saturated cholesterol and crown ether in CHCl3were determined.The cavity size and negative electricity of the ether ring of crown ethe,r molecules are favorable to the selective complexation with metal cations(M+,e.g. Li+Na+,K+) in the aqueous solution. The change of[M+](10-4-10-1mol/L)would result in a Nernst corresponding in the membrane potential.
    Studies on the Synthesis and Biological Activities of Aryl Amidoxime Derivatives Including P atom
    JIN Gui-Yu, XIE Min-Yu, ZHAO Guo-Feng, LIU Zhong-Fa
    1995, 16(8):  1241-1244. 
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    By the reactions of aryl amidoximes(I)with thiophosphoryl chlorides(Ⅱ and Ⅲ)and thiophosphoryl isothiocyanates(Ⅳ),14 O-aryl amidoximyl thiophosphates(Ⅴ)and 5 heterocyclic compounds(Ⅵ)including Patom were synthesized in this paper.Their structures were characterized by 1HNMR,IR,MS and elementary analysis. The preliminary biological tests indicated that the compound Ⅴ has a fungicidal activity.
    Structure of a New Alkaloid from the Roots of Glycyrrhiza Yunnanensis
    HU Jin-Feng, SHEN Feng-Jia
    1995, 16(8):  1245-1247. 
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    Anew alkaloid isolated from the roots of Glycyrrhiza Yunnanensis Chang f.et.L.K.Tai with the formula C14H18O2N2,named as glyyunnanenine.The crystal structure has been determined by elemental analysis,UV,IR,FAB-MS,EI-MS,1HNMR,13CNMR,DEPT(90°,135°) and X-ray diffraction analysis.The crystal is orthorhombic with space group P212121,a=0.9629(1) nm,b=1.0848(1) nm,c=1.250(2) nm,V=1.3508(2)nm3,Mw=246.31,Z=4,D=1.253g/cm3,μ(Mo-Ka)=6. 458 cm-1,F(000)=528.Atotal of 1168 independent reflections were observed.The final R=0.058 and Rw=0.066.
    The Insect Antifeedantal Sesquiterpenoids From Celastrus Orbiculatus(I)
    WANG Ming-An, CHEN Fu-Heng
    1995, 16(8):  1248-1250. 
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    Two new and one known insect antifeedantal sesquiterpenoid compounds were isolated from Celastrus orbiculatus,their structures were elucidated as 1β,2β-diacetoxy-9α-cinnamoyloxy-β-dihydroagarofuran(1),1β,2β-diacetoxy-6α-benzoyloxy-9α-cinnamoyloxy-β-dihydroagarofuran(2),1β-acetoxy-9α-cinnamoyloxy-β-dihydroagarofuran(3)by UV,IR,MS and 1HNMR,13CNMR,DEPT,1H-1H COSY,13C-1H COSY,NOEDS.
    Isomerization of Alkynylformolhydrazone Catalyzed by Iridium Complex
    MA Chun-Lin, MA Yong-Xiang, LU Xi-Yan
    1995, 16(8):  1251-1253. 
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    The isomerization of alkynylformolhydrazone 1a-ecatalyzed by IrH5(i-Pr3P)2complex was studied. The isomerization of substrate 1a,bgives 2E,4E-dienhydrazone 2a,b;but under the same reactive condition,the substrate 1(c-e) is isomerizated to 1Z,3Z-dienazo-compound 3c-e.The 2a,bcan be hydrosized to produce 2E,4E-dienaldehyde.So this is a high stereoselective synthetic approach of 2E,4E-dienaldehyde and 1Z,3Z-dienazo-compound. All the compounds were characterized by means of elementary analysis,IR,1HNMR and MS spectra.
    Synthesis of Ethyl Esters of γ-[N1-Substituted-1,4,5,6-tetrahydro(or 1,6-dihydro)-6-oxo-3-pyridazinamide]butyric Acid
    XU Feng-Rong, WANG Shu-Yu, XU Ping, LI Hui, HU Chang-Feng, OUYANG Li
    1995, 16(8):  1254-1256. 
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    Tetrahydro-6-oxo-3-pyridazinecarboxylic acid(I) was obtained by the condensate of α-oxoglutaric acid with hydrazine hydrate.Iwas dehydrogenated to give 1,6dihydro-6-oxo-3-pyridazinecarboxylic acid(Ⅱ).Under the phase transfer catalysis,Ⅲ and Ⅳwere converted into corresponding N1-substituted-1,4,5,6-tetrahydro-6-oxo-3-pyridazinecarboxylic acids(Ⅴ)and N1-substituted-1,6-dihydro-6-oxo-3-pyridazinecarboxylic acids(Ⅵ),which then condensated with ethyl ester of γ-amino butyric acid.Ten ethyl esters of γ-[N1-substituted-1,4,5,6-tetrahydro(or 1,6-dihydro)-6-oxo-3-pyridazinamide]butyric acid(Ⅶa c and Ⅷa e)were synthesized. All compounds synthesized here have not been found in the literature.
    Synthesis of 3-Phenyl-5-substituted Anilino-6-methyl-1,2,4-triazine
    LU Zhong-E, ZENG Run-Sheng, XI Hai-Tao
    1995, 16(8):  1257-1258. 
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    α-Acetyl-N-substituted phenyl thioformanilide reacted with N'-aminobenzamidine hydriodide in acidic medium to form 3-phenyl-5-substituted anilino-6-methyl-1,2, 4-triazine.In this paper,seven heterocyclic compounds were synthesized by this method.
    Ab initio Study on the Structure of 2,4-Dimethyl-1,3-pentadiene
    LI Xue-Kui, ZHAO Bing, ZHAO Yong-Nian, LI Bo-Fu, SUN Jia-Zhong
    1995, 16(8):  1259-1264. 
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    Various conformers of 2,4-PD have been studied using ab initio calculation with different basis sets.It has been found that s-trans and s-cis are stable conformers,the strans is more stable one.Geometrical parameters and mulliken analysis of these two stable conformers have been studied.The influence of basis set on geometrical parameters was discussed.Thermodynamic constants of the stable conformers were calculated and compared with experimental result.
    A Theoretical Study of Structures and Electronic Spectra of C28X4(X=H,Cl)and CX4(X=H,Cl)
    FENG Ji-Kang, TIAN ei-Quan, TENG Qi-wen, SUN Jia-Zhong
    1995, 16(8):  1265-1269. 
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    The geometry optimization of C28X4(X=H,Cl)and CX4(X=H,Cl)has been performed by using INDO series methods and the Td symmetry structure has been obtained. There are four kinds of bonds and four kinds of different atoms for C28X4.The ground states of C28X4are stable closed-shell molecules.On the basis of these geomitries,the electronic spectra of the ablve molecules have been calculated.The electronic spectra of C28X4are predicted theoretically.
    Studies on States of Cytochrome C Molecules in Aquous Solutions Using Synchronous Fluorescence Spectroscopy
    CHOU Ju, QU Xiao-Gang, LU Tian-Hong, WU Yue
    1995, 16(8):  1270-1274. 
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    The states of cytochrome Cmolecules in aquous solution were studied with synchronous fluorescence spectroscopy.It was found that the synchronous fluorescent spectra of cytochrome Cwere contribuited by tyrosine and tryptophan residues separately at △λ=20 nm and △λ=80 nm.The peak position in synchronous fluorescent spectra of tyrosine residues in cytochrome Cmolecule does not change with its concentriation,but that of tryptophan residue changes with its concentration.Only one peak at 340.0 nm was observed in the dilute solution of cytochrome C.With increasing the concentration of cytochrome C,a new peak at 304.0 nm appeared.The peak at 340.0 nm disappeared and only one peak at 304.0 nm was obderved at a higher concentration of cytochrome C.It may originate from the change of aggregation states of cytochrome Cmolecules and it was considered that the peak at 340.0 nm was attributed to the monomer and peak at 304.0 nm was due to the dimmer or oligomers.When urea was added into cytochrome Csolution in which both monomer and dimmer or oligomers exist,cytochrome Cmolecules do not denature in the range of the specific concentrations of urea.The concentration of monomer of cytochrome Cmolecules increased and that of aggregation states decreased by adding urea.Therefore,the synchronous fluorescence spectroscopy can be used to identify monomer and aggregation states of cytochrome Cmolecules.
    Studies on the Correlativity of Atom-pair Interaction Energies and Organic IR Spectra
    DENG Ke-Jian, SHEN Rui-Man, CUI Bo, TAO Yong
    1995, 16(8):  1275-1279. 
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    Aquick,definitive analyzing method of IRspectra is preliminarily studied.We relate the peak position of IR stretching vibration frequencies of the bonds between Cand H,C and C,C and O,C and N with correspondent atom-pair interaction energies computed by MNDO method.Their correlativities are well obtained. The correlative curves and equations are adopted in least square method,and the correspondent correlation coefficients are all higher than 0.97 The correlations quantitatively explain the factors affecting the stretching vibration frequency shifts of C H,C C,C=C,CC,C O,C=O,C=N and C≡N in orgainc molecules,such as unsaturated,induced,medium,ring tension,conjugation.
    Gas Phase Synthesis of Derivative of C60──C60S+
    LIU Zi-Yang, HAO Guo-Lun, GUO Xing-Hua, LIU Shu-Ying
    1995, 16(8):  1280-1282. 
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    Gas phase ion-molecular reactions of C60with the ion system of CS2have been studied in the ion source of mass spectrometer.It was found for the first time that the sulfuric derivative of C60──C60S+was the main ions in the ion source,they did not react with C60to form adduct ions due to their highly saturated structures.According to the dynamic analysis, the product ion came from the reaction of C60with the fragment ion S+.The adduct ion may have the structure of epsulfide that is advantageous in energy.
    Fast Convergent Investigation in Potential-harmonic Expansion Scheme
    WANG Yi-Xuan, DENG Cong-Hao
    1995, 16(8):  1283-1285. 
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    We present the correlation-function potential-harmonic generalized Laguerre function expansion method(CFPHGLF)for directly solving the Schrodinger equation for heliumlike system.In CFPHGLF scheme with the simplest spatially symmetric correlation function exp[-Z(r1+r2)],the eigenenergies for the excited(n 1S,n=2-4)states agree well with the variational ones,while the ground state eigenenergy far from the variational one. The results for the excited states are also comparable to the CFHHGLF calculation of the full basis set with the same correlation function.
    Studies on Self-association of Alcohols in Diphenyl Methane and Cross-association of Alcohols in Dibenzyl Ether by Gas-liquid Chromatography at Finite Concentrations
    WANG Yi-Lin, ZHOU Xiao-Xian, LI Song-Lin, ZHENG Guo-Kang
    1995, 16(8):  1286-1288. 
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    The activity coefficients of C4alcohols in diphenyl methane and in dibenzyl ether at 313.15K were measured by gas-liquid finite concentration chromatography.The data were treated with Wiehe-Bagley(W-B)continuous association model,and then the self-association constants KAwere evaluated.According to the concept of homomorph,taking the value of KAof one alcohol in diphenyl methane as the value of the same alcohol in dibenzyl ether,the cross association constants KABof alcohol with dibenzyl ether were obtained.It is shown that the W-Bmodel can be fitted to the experimental result satisfactorily.
    Studies on Mechanism of CO Hydrogenation over Ni/Al2O3
    HU Yun-Hang, WAN Hui-Lin, GUAN Yu-De, LIN Heng-Sheng
    1995, 16(8):  1289-1291. 
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    The mechanism of CO hydrogenation to CH4over Ni catalysts was studied by response method of differential pulses and BOC-MP method.It was suggested that the dissociation of CO under the promotion of hydrogen was favorable over Ni(111),whereas the direct dissociation of CO was favorable over Ni(100).Moreover,it was shown that hydrogenation of surface C to CH species was the rate-determining step.
    Studies on Synthesis and Properties of Aluminium Magnesium Hydroxide Positive Sol
    HOU Wan-Guo, ZHANG Chun-Guang, SUN De-Jun, LIANG Xiao-Li, WANG Guo-Ting
    1995, 16(8):  1292-1294. 
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    A positive sol of aluminium magnesium hydroxide was synthesized by non-steady coprecipitation.The synthesis mechanism,shape,chemical composition, electrical property and thermal stability of colloidal particles were studied by X-ray diffraction, transmission electron microscope,chemical analysis,spectroanalysis and measuring of electrophoretic mobilities.The colloidal particles are tiny platelets with an average diameter of about 30 nm,and may aggregate with"oxygen-bridge"in water medium.In the process of synthesis,the peptization is the transformation process from amorphous to crystalline.The chemical compositions of particles are dependent on the composition of raw material.When the ratios of Mg/Al in raw material are 1:2,1:1 and 2:1,the chemical formulas of colloidal particles are Mg0.27Al(OH)3.07Cl0.47·0. 86H2O,Mg0.43Al(OH)3.72Cl0.14·0.5H2O, Mg0.96Al(OH)4.50Cl0.42·1.45H2O,respectively.The electrophoretic mobilities and thermal stability of the colloidal particles increase with increasing the content of magnesium in chemical composition of the particles.
    Studies on the Critical Micelle Concentration of N-Alkylbetaines by Fluorescence Probe
    REN Xue-Zhen, LI Gan-Zuo, WANG Hong-Li, ZHAI Li-Min, SUI Wei-Pin, XU Xin-Yan
    1995, 16(8):  1295-1297. 
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    The fluorescence characteristics of I5/I1and I3/I1of pyrene which is sensitive to the environment of probe was used to study the critical micelle concentration(cmc)of N-dodecylbetaine and N-tetradecylbetaine.The effect of salt concentration on the cmc values was studied.The results obtained indicate that cmc values determined from the parameters I5/I1of pyrene are close to that from the surface tension measurements,and more accurate than that from I3/I1.
    The Microwave-induced Plasma Chemical Reaction of the Lower Alcohol
    WANG Zhen, HONG Pin-Jie, ZHANG Cheng-Cong, DAI Shu-Shan
    1995, 16(8):  1298-1300. 
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    Amicrowave source with power 0-100 W,continuously adjustable,operating at a frequency of 2450 MHz and a surfatron discharge cavity was used for the experiment.The microwave-puncture curves of air and various alcohols(CH3OH,C2H5OH,n-C3H7OH and i-C3H7OH)observed show that the lower-pressure vapor of alcohol was dissociated easier than air,resulting in plasma.The reactor effluent gases were analyzed by gas chromatography with FIdetector or TC-FI two-dimensional chromatography method on line.The electron temperature(Te)of the alcohol plasma was identified using Langmuir double-probe.The results show that the products of plasma reaction were composed of H2,H2O,CO,CH4,C2H4,C2H6,C3H6and C3H8, but C2H4was the main product.Not only the nature of the alcohol itself,but also the microwave power was responsible for the product abundance.This kind of reaction proceeded through a free radical mechanism,so the distribution and quantity of products show the species and quantity of free radicals in plasma.The yield of C2H4was increasing as the input-power increased,up to the maximum then followed by the decreasing,and the carbon deposit on the wall of reactor could be observed,which implied the deepdissociation took place in the case of higher power,and the higher hydrocarbon was not easily produced.
    Anti-oxidation Treatment on Carbon Fiber
    TANG Long-Gui
    1995, 16(8):  1301-1305. 
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    The anti-oxidation performance of carbon fiber in high temperature atmosphere was increased greatly after it was treated with boron agents.It was shown by means of TGA,SEM,XPS and WAXD that the treatment elevated the decomposition point above 268℃, and increased the average oxidation activation energy doubly,from 98.6kJ/mol of the untreated fiber to 220.3kJ/mol of the treated fiber,with the first order of the fiber oxidation reaction under non-isothermal conditions,and increased the life-time many times.During the process,however,the mechanical properties developed slightly.
    Studies on the Microozonization-TLC Method for the Separation and Analysis of Copolymerization Products of α-Pinene/Styrene
    DENG Yun-Xiang, PENG Chao-Pan, LIU Ping, ZHANG Ren-Jun, ZENG Long-Mei
    1995, 16(8):  1306-1310. 
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    The microozonization-thin layer chromatography(TLC)method for the separation and analysis of copolymerization products of α-pinene/styrene has been established.It is the process that the copolymerization products is ozonized first under condition of selective and quantitative ozonization of endo-double bond in the sample;and then the ozonide obtained is separated into two samples of insoluble and soluble part in methanol;further,both of the two samples are separated with the TLC respectively into two parts,and four fractions which are an ozonized poly(α-pinene),two types of ozoni zed copolymers of α-pinene/styrene and a poly(styrene)are collected with the way in Fig.1.Characterized results have been obtained by IR,NMR,MS and GPC evidencing that the homopolymer and the copolymer can be separated from the copolymerization product fully,and components in the copolymer can be determined in precise terms.
    The Stability Effect of Polymer on the PbS Nanoparticles
    GAO Ming-Yuan, YANG Yi, ZHANG Guang-Chan, BIAN Feng-Lan, YANG Bai, SHEN Jia-Cong
    1995, 16(8):  1311-1314. 
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    Using SAXS method,the particle size and its distribution of the PbSnanoparticles doped in the polymer matrices were characterized.Based on the SAXS results together with direct observation,the effect of the reaction conditions on the stability of the composite system was obtained.The experiment revealed that the amount of the H2S used in reacting with the P-Pb can affect the PbS particle size and its distribution, but this effect is very small,because of the good stability effect of polymer on the PbS nanoparticles,the composite system possesses a long-term stability.While the particle size and its distribution can be changed in a larger range when small organic lead salt was introduced into the reaction system.The particle size and its distribution were growing as the increasing of the proportion of PB(MA)2to P-Pb.As a result,the composite system lost its stability at high Pb(MA)2concentration.
    Synthesis of Crosslinked Second Order Nonlinear Optical Polymers with High Tg
    YANG Chun-Cai, JING Xia-Bin, WANG Hua-Bin, WANG Quan-Fu, HAN Xiao-Zu, WANG Fo-Song
    1995, 16(8):  1315-1318. 
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    Synthesis and characterization of a diamino dihydroxyl azo compound were reported.The crosslinking reaction process of the diamino dihydroxyl azo compound with the biuret of hexamethylene diisocyanate was studied by FTIR.The glass transition temperatures of crosslinked polymers were measured by DSC.The orientation and oriented stability of crosslinked and poled polymers were studied by UV-Vis spectra.
    The Anomalous Temperature Dependence of Fluorescence Spectrum of Poly(2,5-di-n-butoxybenzene)
    MA Yu-Guang, WU Ying, ZHANG Hai-Feng, TIAN Wen-Jing, SHEN Jia-Cong, LIU Shi-Yong, SUN Meng
    1995, 16(8):  1319-1320. 
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    Poly(2,5-di-n-butoxybenzene)exhibits a strong fluorescence in the blue regions. The effects of temperature have been studied carefully.We found an anomalous temperature dependence of fluorescence spectrum of poly(2,5-di-n-butoxybenzene).When the temperature increases from 77 to 373 K,the intensity of fluorescence increases 30%.The temperature variations should have an effect on conformation of poly(2,5-di-n-butoxybenzene)from linear to coil.The coil conformation limits the exciton motile in a small region and decreases the trapping of exciton.
    Fluorometric Study on the Hydrophobic Microdomain Structure of Hydrophobically Modified Polyacrylamide
    QIU Xing-Ping, ZHANG XUe-Rong, DING Ma-Tai
    1995, 16(8):  1321-1323. 
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    In this paper,1-naphthol has been used as a fluorescence probe to investigate the hydrophobic microdomain structure formed by hydrophobically modified polyacrylamide in aqueous solution.It was found that 1-naphthol molecules are soluble in spherical SDS micelles but insoluble in the hydrophobic microdomains of AM-co-HDMAM.The solubility difference indicated that,owing to the steric hindrance of polymer backbone,the hydrophobic microdomains of AM-co-HDMAM should have a less integrated micellar structure than SDS micelles.
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