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Table of Content

    24 February 2003, Volume 24 Issue 2
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    Preface
    Phase Relation of 2MgO·2B2O3·MgCl2·14H2O-7.8%H3BO3-H2O System at Various Temperatures
    LIU Zhi-Hong, HU Man-Cheng, GAO Shi-Yang
    2003, 24(2):  189-194. 
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    The phase relation of 2MgO·2B2O3·MgCl2·14H20-7.8%H3BO3-H20 system at various temperatures has been studied by FTIR spectroscopy, XRD, TG, as well as chemical analyses. The phase transformation product is MgO·2B2O3·9H20 at 0-22 ℃, MgO·2B2O3·7.5 H20 at 22-68 ℃, MgO·2B2O3·7H20 at 68-95 ℃, MgO·2B2O3·5H20 at 95-98.8 ℃, MgO·B2O3·3H20 at 100-110 ℃, 2MgO·B2O3·2H20 at 110-120 ℃, 2MgO·B2O3·1.5H20 at 120-170 ℃, and 2MgO·B2O3·H20 at 170-200 ℃, respectively. The mechanisms of dissolution and phase transformation have been proposed and discussed.
    Articles
    Synthesis, Properties and Phase Equilibrium of Zn(NO3)2-Leu-H2O System(25 ℃)
    GAO Sheng-Li, YANG Xu-Wu, CHEN San-Ping, LI Huan-Yong, SHI Qi-Zhen
    2003, 24(2):  195-199. 
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    The solubility of Zn(NO3)2-Leu-H20 system at 25 ℃ in the entire concentration range has been investigated by phase equilibrium method. The corresponding phase diagram and refractive index diagram have been constructed. The incongruently soluble complexes [Zn(Leu)(NO3)2(H20)]·H20(A) and [Zn(Leu)2(NO3)2·H20(B)] which have not been reported in literature, have been prepared. The compounds are characterized by IR spectra, TG-DTG, as well as chemical and elemental analyses. The constant volume combustion energies of the complexes, ΔcE(complex, s), have been determined by a precision rotating bomb calorimeter at 298.15 K. The standard enthalpies of combustion, ΔcHmθ(complex, s), and standard enthalpies of formation, ΔfHmθ(complex, s), are calculated for the complexes.
    Synthesis of Tetra(4-n-lauryloyloxyphenyl)porphyrin Complexes and Its Liquid Crystalline Characterization
    LIU Wei, SHI Yu-Hua, WANG Yin-Jie, SHI Tong-Shun, ZHANG Wan-Jin
    2003, 24(2):  200-204. 
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    Tetra-(4-n-lauryloxyphenyl)porphyrin and its complexes of Mn(Ⅲ), Fe(Ⅲ), Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ) have been synthesized. The compounds were determined and measured by elemental analysis, UV-Vis, FTIR photoacoustic spectrum, 1HNMR and molar conductivity. The Fourier transform infrared photoacoustic of TLPPH2 and its complexes in the range of 3 600-190cm-1 were measured and investigated. The vibration coupling between the M-N stretching and the porphyrin ring deformation appears at 250.0cm-1. The band at 320cm-1 is due to M-Cl stretching vibration. Metal sensitive bands were found at～1352, ～1018, ～993, ～800 and 231cm-1. The stability and the structure of the liquid crystalline phases are examined by optical microscopy and differential scanning calorimetry(DSC). Zn complex exhibits lower phase transition temperature at-50.67 ℃ and wide mesophase range at 143 ℃.
    Influence of Catalysts Particle Size on Alkylation of Isobutane with Butene over Hβ Zeolites
    WANG Run-Wei, LIN Sen, MENG Xiang-Ju, LI Bin-Song, JIANG Da-Zhen, XIAO Feng-Shou, QIU Shi-Lun 
    2003, 24(2):  205-207. 
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    A series of β zeolite with various particle sizes were hydrothermally synthesized and characterized in detail. In the alkylation of isobutane with butene the activities of the catalysts increase with the the particle size of the zeolite decreasing(40 μm-20 nm). The selectivity for C 8 decreases with the the particle size of the zeolite decreasing.
    A New Orange-red Long-lasting Phosphor Material Y2O2S∶ Sm3+
    LEI Bing-Fu, LIU Ying-Liang, TANG Gong-Ben, YE Ze-Ren, SHI Chun-Shan
    2003, 24(2):  208-210. 
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    A new Sm3+ doped yttrium oxysulfide phosphor, which has the long-lasting phosphorescence, was synthesized by flux fusion method. The phosphors showed three typical transitions of Sm3+ ( 4G5/2→ 6H J, J=5/2,7/2,9/2), and the emission peaks located at 570, 606 and 659 nm respectively. A prominent luminescence and phosphorescence in orange-red can be seen in this phosphor when illuminated with UV light or visible light. The synthesized phosphors were characterized by X-ray diffraction, the excitation and photoluminescence spectra, and the after-glow intensity decay curve. The result shows that the Y2O2S∶ Sm3+ phosphor is another efficient orange-red phosphor.
    Comparative Studies on the Transport Across Human Erythrocyte Membrane by Metal Ions Ni2+ and Cd2+ with Different Configurations of Electron
    WU Gang, QIAO Xiu-Wen, LI Rong-Chang, WANG Kui
    2003, 24(2):  211-213. 
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    The rate constants of transmembrane transport of Ni2+and Cd2+ with the same charge and different configurations of electron were determined in this experiment, and their first-order kinetic rate constant is as follows: for Ni2+, k(Ni2+)=0.002 0 h-1, and for Cd2+, k(Cd2+)=0.021 h-1. There are large differences between their rates of transmemebrane transport. The mechanisms of transmembrane transport of Ni2+and Cd2+ are studied at the same time. The influences of the concentration of metal ions, pH of solution and the transport inhibitor on the uptake of Ni2+and Cd2+ by human erythrocytes have been studied. The results show that Ni2+ions pass through the membrane by passive diffusion, while for Cd2+, some of them are transported by the anion channel, the others by passive diffusion. Because there are different configurations of electron in the two ions, there are large difference in action of them with protein in the membrane of human erythrocytes.
    Investigation on the Interaction of β-K4H3 [SiW9O37(CpTi)3]·11H2O Polyacid Derivative with DNA
    LI Jian-Xin, WANG Ying, WANG Xiao-Hong, LIU Ju-Tao, LI Yu-Xin, HUANG Bai-Qu, LIU Jing-Fu
    2003, 24(2):  214-215. 
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    The interaction between β-K4H3 [SiW9O37(CpTi)3]·11H20 and DNA was investigated by agarose gel electrophoresis. The results suggest that β-K4H3[SiW9O37(CpTi)3]·11H20 can degrade the genomic DNA. The treatment of plasmid DNA with β-K4H3 [SiW9O37(CpTi)3]·11H20 resulted in a fast moving band in front of the three normal conformations(super coiled DNA, linear DNA and relaxed circular DNA) in agarose gel electrophoresis. These results indicate that this chemical material may have the ability to specifically cleavage DNA or to alter conformation of DNA molecules.
    Studies on Quantum Dots Synthesized in Aqueous Solution for Biological Labeling
    LIN Zhang-Bi, SU Xing-Guang, ZHANG Hao, MU Ying, SUN Ye, HU Hai, YANG Bai, YAN Gang-Lin, LUO Gui-Min, JIN Qin-Han
    2003, 24(2):  216-220. 
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    CdTe semiconductor nanoparticles were synthesized in aqueous solution by using mercaptopropyl acid(HS-CH2CH2COOH) as the stabilizer. The nanocrystals exhibit a strong, stable and narrow band luminescence(FWHM=40 nm). The average size estimated from TEM graph is ca. 3 nm. The applicability of the resulting mercaptopropyl acid modified CdTe nanoparticles to the labeling of biomoleculestrypsin was studied in this paper. The absorption spectrum of CdTe-trypsin solution was flatter than that of CdTe nanoparticles over the wavelength range of 400 to 600 nm. While the emission spectrum of CdTe-trypsin solution shows a blue-shift in the emission peak, the intrinsic emission band width is unchanged. It was proved that the shift of the emission peak was the result of the conjugation between CdTe nanoparticles and trypsin, but not of the oxidation caused by O2. Furthermore, heating could accelerate the speed of conjugation between CdTe nanoparticles and trypsin.
    Studies on a Novel Extraction Reagent for Oil in Water
    ZHENG Jian, YU Ai-Min, ZHOU Jian-Guang, LI Bao-Hua, CHEN Huan-Wen, ZHANG Han-Qi, JIN Qin-Han, LIU Ting-Liang, WANG Xiao-Hui, LI Guo-Gang
    2003, 24(2):  221-225. 
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    In this paper, a novel extraction reagent, tetrachloroethylene for the determination of oil in water with infrared spectrophotometry was chosen, and a special purification procedure for purifying the extraction reagent was developed. In addition, a comparative study between the novel extraction reagent and the commonly used carbon tetrachloride was also carried out.
    Studies on Amide Ⅲ Infrared Bands for the Secondary Structure Determination of Proteins
    XIE Meng-Xia, LIU Yuan
    2003, 24(2):  226-231. 
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    Fourier transform infrared spectroscopy is increasingly becoming an important method for quantitatively determining the secondary structure of proteins. Amide Ⅰ band(1 600-1 700cm-1) and amide Ⅲ (1 220-1 330cm-1) are two main bands for this purposes. Amide Ⅲ was neglected because of its relatively weak in signals, but there is not interference from water and water vapor vibration bands and it is more sensitive to the changes of protein secondary structure. In this paper, proteins BSA and RNase A were denatured by methanol. The component bands of secondary structure in amide Ⅲ were assigned by combining the quantitative results of amide Ⅰ band. α-Helix 1 330-1 290cm-1; β-turn 1 295-1 265cm-1; Random coil 1 270-1 245cm-1 and β-sheet 1 250-1 220cm-1. The overlapping area between the neighboring bands of different structures, such as 1 290-1 295cm-1, 1 265-1 270cm-1, 1 245-1 250cm-1, can be determined according to quantitative results of amide Ⅰ band. By using above assignments, the quantitative analysis results of the proteins in which the secondary structures have been known were consistent with that of X-ray data and amide Ⅰ band.
    Studies on a Microfluidic Chip Based on the Continuous Flow PCR Amplification System
    LIU Jin-Hua, YIN Xue-Feng, XU Guang-Ming, FANG Zhao-Lun, CHEN Huai-Zeng
    2003, 24(2):  232-235. 
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    A PCR amplification system comprising a syringe pump sample processor, a microfluidic PCR chip and a 3-temperature-zone heating block was developed in this work. The system is capable of performing continuous PCR amplification with a low carryover between neighboring samples. The substrate thickness and thermal insulation of the temperature control unit were optimized. A 24-cycle PCR amplification of a 500-base pair fragment from λ-DNA was successfully performed with a total reaction time of 4 9 min.
    Effect of Porous Interfacial Layer of Carbon Nanotube Modified Electrodes on Electrochemical Discrimination of Dopamine from Ascorbic Acid
    WANG Zong-Hua, LIU Jun, YAN Liu-Shui, WANG Yi-Ming, LUO Guo-An
    2003, 24(2):  236-240. 
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    Modified electrodes were firstly constructed by casting or intercalating carbon nanotube on graphite surface, which resulted in a favorable discrimination of dopamine(DA) and ascorbic acid(AA), and the anodic potential difference(ΔEpa) was more than 250 mV. Taking DA and AA as model compounds, further research on the separation mechanism of these modified electrodes was investigated by employing cyclic voltammetric and differential pulse voltammetric techniques. The results show that the solvent and the surfactant have a strong effect on ΔEpa. Various types of carbon nanotubes(single wall, multi wall or helix multi wall) presented differences of ΔEpa, while the diameter of the same kind of carbon nanotubes proved to have little effect on it. Furthermore, significant change on ΔEpa was observed when carbon nanotube was oxidized by acids with different oxidation capability. All the results showed that the discrimination of DA from AA was mainly attributed to the tubular structure of the nanotubes and its functional group.
    Application of Heuristic Evolving Latent Projection(HELP) in the Resolution of Tailing Coeluting Chromatograms
    QI Yun-Peng, WU Yu-Tian, LI Tong-Hua, CHAI Yi-Feng, WANG Bin, ZHANG Guo-Qing
    2003, 24(2):  241-244. 
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    Heuristic evolving latent projection(HELP) has been successfully applied in the resolution of coeluting chromatograms of the complicated systems. When the chromatogram tails, the selective region shown by the evolving latent projection graph(ELPG) may contain the information of the prior tailing components, on which unsatisfactory results may be obtained by using HELP. In this work, a region near the end of the tailing component, where the prior components have almost disappeared was chosen as the selective region; at the same time, a new quantitative method was presented: 2D data of the determined component was decomposed by principle component analysis(PCA), and the standard chromatogram will be induced into quantitation. An experimental system composed of enoxacin, norfloxacin and ciprofloxacin was resolved by HELP. It was shown that the HELP used can improve the resolution of tailing coeluting chromatograms greatly and give satisfactory quantitative results.
    A Novel NO Microsensor and Its Application in the Detection of NO in Myocardial Cells
    ZHU Min, LIU Min, SHI Guo-Yue, CHEN Jun-Shui, JIN Li-Tong
    2003, 24(2):  245-248. 
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    A novel sensitive, selective and stable nitric oxide(NO) microsensor is described, which is modified by nano Au colloid and Nafion. Determined by Atomic Forced Microscope, the diameter of Au colloid particles is from 7 to 14 nanometers. The detection of NO is based on the nano Au particles catalysis of NO oxidation at an anodic potential of +0.74 V(vs. SCE). The microsensor showed a low detection limit, high selectivity and sensitivity for NO determination. The oxidation current(measured by differential pulse amperometric technique) was linear with NO concentration ranging from 1.0×10-7 to 4.0×10-5 mol/L with a calculated detection limit of 5.0×10-8 mol/L(S/N=3). Using the microsensor, the direct, real time production of NO in the myocardial cells was continuously measured, which showed the NO levels was increased by stimulating with L-arginine and acetylcholine.
    Studies on the Interactions Between Morin and Its Cu(Ⅱ)-, Zn(Ⅱ)-Complexes with DNA
    SONG Yu-Min, KANG Jing-Wan, LU Xiao-Quan, WANG Zhi-Hua, GAO Jin-Zhang
    2003, 24(2):  249-251. 
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    The interactions of Morin and its Cu(Ⅱ)-, Zn(Ⅱ)-complexes with calf thymus DNA have been studied by using fluorimetric and electrochemical methods. Cu(Ⅱ)-, Zn(Ⅱ)-complexes have different spectra and electrochemical characteristics from that of Morin in the presence of DNA. The results suggest that Morin and its complexes can both bind to DNA, but the binding mode is different. The complexes bind to DNA mainly like EB by intercalation, while Morin binds in a non-intercalating mode.
    Simultaneous Separation and Determination of Nine Metal Cations with Single-column Ion Chromatography
    XU Ji-Ming, XIAN Yue-Zhong, WANG Yan-Ping, SHI Guo-Yue, JIN Li-Tong
    2003, 24(2):  252-254. 
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    A method for simultaneous determination of nine cations including Fe3+, Cu2+, Ni2+, Zn2+, Co2+, Fe2+, Cd2+, Mg2+ and Ca2+ by single-column ion chromatography with a conductivity detector was developed. The optimum composition of eluent was 6 mmol/L malic acid and 3 mmol/L ethylenediamine(pH=4.0). The effects of malic acid concentration, ethylenediamine concentration and pH value on retention time were studied in details. The method was used to determine Fe, Cu, Zn, Mg and Ca in whole blood and serum with satisfactory results.
    A Study of a Novel Organic Fluorescent Core-shell Nanoparticle
    DUAN Jing-Hua, WANG Ke-Min, TAN Wei-Hong, HE Xiao-Xiao, HE Chun-Mei, LIU Bin, LI Du, HUANG Shan-Sheng, YANG Xiao-Hai, MO Yuan-Yao
    2003, 24(2):  255-259. 
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    A novel fluorescent core-shell nanoparticle has been developed by encapsulating the fluorophore into silica shell with a reverse microemulsion technique. The FITC encapsulation is greatly enhanced by conjucting a water-soluble protein IgG which significantly reduces FITC leaching from the nanoparticles when immersed inside water. The FITC leaching problem of the nanoparticles prepared with IgG has been much less severe than that with the FITC nanoparticles prepared with unmodified dye or dye modified with dextrans of higher molecular weight. The fluorescent core-shell nanoparticles are also pH sensible. They can be used as pH optical sensors inside cell phagocytosed by murine macrophages.
    Synthesis and Antiangiogenic Activities of 1,3-Dihydro-1,3-dioxo-2H-isoindole Derivatives
    DENG Yong, ZHONG Yu-Guo, SHEN Yi, LIU Shao-Hua
    2003, 24(2):  260-264. 
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    The growth of malignant tumors has been shown to be dependent on the evelopment of new blood vessels. Blocking tumor-induced angiogenesis is an efficiency strategy to prevent and cure cancer. It has been shown that the angiogenic process depends on vascular endothelial cell migration and invasion processes regulated by cell adhesion receptor. The integrin αvβ3 is such a cell adhesion receptor. Recent studies show the integrin αvβ3 and extracellular matrix can recognize each other through Arg-Gly-Asp(RGD) sequence, some peptides containing RGD sequence antagonists can inhibit embryonic neovascularization, tumor-induced angiogenesis, and tumor growth. According to the structure-activity relationships and antiangiogenic mechanism of RGD sequence, we use thalidomide as the leading structure to design and synthesize five 5-carboxy-1,3-dihydro-1,3-dioxo-2H-isoindole derivatives. All of them were first reported and their structures were confirmed by elementary analysis, IR and 1HNMR spectra. The results of preliminary antiangiogenic tests in vitro showed that most target compounds could inhibit ECV 304 proliferation. Moreover, it has been proved that the inhibition of endothelial cell proliferation was not the result of cytotoxic effect of target compounds.
    Synthesis and Carbon Unit Transfer Reactions of Ethenyl Substituted N5, N10-C+R-tetrahydrofolate Coenzymes
    WANG Lan-Ying, HU Zhi-Biao, SHI Zhen
    2003, 24(2):  265-269. 
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    Eight 1,3-dimethyl-2-alkyl ethenyl substituted benzimidazolium salts which were used as the models of N5, N10-C+R-tetrahydrofolate(THF) coenzymes at formic acid oxidation level were synthesized by the reaction of o-phenylenediamine with acetic acid giving 2-methyl benzimidazole, and the consecutive reaction with methyl iodide and aldehydes. Their molecular structures were characterized by elemental analysis, 1HNMR, IR, MS and UV-Vis spectra. These model compounds can react with nucleophilic reagents(Grignard reagents) to give alkyl ethenyl substituted one carbon unit transfer products α,β-unsaturated ketones. A convenient biomimetic method for synthesis of α,β-unsaturated ketones was provided.
    Synthesis of 16-Hydroxy-6,7-didehydraferruginyl Methyl Ether and Its Analogues with 16-Oxidant Group
    SHEN Hao, LI An-Pai, WANG Hui, DU Zhen-Ting, WU Tong-Xing, PAN Xin-Fu
    2003, 24(2):  270-273. 
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    The synthetic strategy of AC→ABC was used, in which α-cyclocitral was used as A ring synthon. The key intermediate 11 was obtained after condensation of α-cyclocitral with triphenyl phosphonium chloride 8, sequently selective reduction by Pd/C and intramolecular cyclization. 16-Hydroxy-6,7-didehy-draferruginyl methyl ether and three analogues with 16-oxidant group were synthesized from this key intermediate via structure modification.
    Synthesis of New Dendritic Chiral BINOL Ligands and Their Applications in Enantioselective Lewis Acid Catalyzed Addition of Diethylzinc to Aldehydes
    FAN Qing-Hua, YANG Xi-Qiang, LIU Guo-Hua, CHEN Xiao-Min, Albert S. C. Chan
    2003, 24(2):  274-277. 
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    The series of new dendritic chiral BINOL ligands(3) were synthesized by condensation reaction of (R)-2,2′-dihydroxy-1,1′-binaphthyl-3,3′-dicarboxylic acid(1) and Fréchet-type poly(aryl ether) dendrons(2) with an amino group at the focal point in moderate reaction yields. All ligands were characterized by 1HNMR, IR and MALDI-TOF-MS spectra, which clearly demonstrated the formation of monodispersed dendritic BINOLs. The titanium complexes of these dendritic ligands obtained by mixing(3) with Ti(OPri)4 4 in dry toluene were found to be efficient catalysts in asymmetric addition of diethylzinc to aldehydes. The size of the dendritic wedges did not significantly influence the enantioselectivity of the catalyst. Most interestingly, when ortho-chlorobenzaldehyde was used as substrate, we found that enantioselectivity increased slightly with increasing generation of the dendrimers.
    Studies on the Synthesis and Properties of Dihydroxy-di(hydroxyethoxy)calix Arene
    LU Kui, ZHAN Hai-Jun, ZHOU Zhi-Xian, WU Yang-Jie
    2003, 24(2):  278-281. 
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    A new compound, 25,27-dihydroxy-26,28-di(hydroxyethoxy) calix arene, was obtained by the reaction of calixarene with iodoethanol. Its structure was characterized by IR, UV, MS, 1HNMR and 13C NMR spectra. The coordination behavior of the product with 4 kinds of rare earth metal(Ⅲ) nitrates in acetonitrile was studied by using fluorescence spectrometry. The stability constants(lgKS) of the complexes of the product with rare earth metal(Ⅲ) nitrates and the Gibbs free energy change(-ΔG°) of the coordination reactions were calculated according to the modified Hilderbrand-Benesi equation. The results indicated that the coordination ability of the product with rare earth metal(Ⅲ) nitrates were stronger.
    Synthesis of meso-5,10,15,20-Tetra[4-(N-pyrrolidinyl)phenyl] Porphyrin and Its Interaction with Bovine Serum Albumin
    GUO Can-Cheng, LI He-Ping, ZHANG Xiao-Bing, TONG Rong-Biao
    2003, 24(2):  282-287. 
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    A novel pyrrolidino-porphyrin, meso-5,10,15,20-tetra[4-(N-pyrrolidinyl)phenyl] porphyrin(TBPPH2), was synthesized based on the porphyrin′s special affinity for cancer cells and the antitumor activity of pyrrolidine compounds. Its structure was characterized by UV-Vis spectra, elemental analysis and 1HNMR. In order to study the possible anticancer activity of TBPPH2, the interaction model based on TBPPH2 and bovine serum albumin(BSA) was built, and the binding mechanism was studied with UV-Vis spectra and fluorescence spectra. The research results indicate that BSA strongly bind to TBPPH2 with the molar ratio of 1∶1, the hydrophobic force was the main binding force, the shortest binding distance r was 2.4 nm, the equilibrium constant KA was 2.51×104 L/mol, the reaction entropy ΔS was 84.18 J/(mol·K), the binding constant KB was 5.13×105 L/mol. The research results show that it is possible for the porphyrins with pyrrolidinyl groups to become a new type of the antitumor drugs.
    Structure and Magnetic Properties of Compounds YCo12-xTix and YFe12-xTix
    WANG Wen-Quan, FU Quan, SU Feng, WANG Xue-Feng, YAN Yu, JIN Han-Min
    2003, 24(2):  288-292. 
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    Structure and magnetic properties of YCo12-xTix and YFe12-xTix compounds have been investigated by using X-ray diffraction and magnetic measurements. It was found that all compounds investigated are almost single phase with the ThMn 12-type structure. X-ray diffraction patterns of magnetically aligned powder samples indicate that the easy magnetization directions(EMD) of YCo12-xTix and YFe12-xTix compounds are along the c-axis at room temperature. The lattice parameters increase monotonically with increasing Ti component for all the compounds investigated. The Curie temperature T c decreases monotonically with increasing Ti component for YCo12-xTix, while Tc of YFe12-xTix is almost independent of Ti component. The saturation magnetization M s decreases with increasing Ti component for both systems. The anisotropy field Ha of YCo12-xTix and YFe12-xTix compounds decreases monotonically with increasing Ti component, which can be understood in terms of a two-sublattice model of anisotropy.
    Interaction Between Sodium Tetradecyl Sulfate-Tetradecyl Triethoxylated Ether Surfactants in Aqueous Solution by 1H NMR
    MAO Shi-Zhen, JIN Zhi-Qiang, WANG Tian-Zhi, WANG Han-Hui, FANG Xiao-Wen, YUAN Han-Zhen, YU Jia-Yong, DU You-Ru
    2003, 24(2):  293-296. 
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    The self-aggregation of sodium tetradecyl sulfate[n-CH3(CH2)13OSO3Na(STS)] and tetradecyl triethoxylated ether[n-CH3(CH2)13O(C2H4O)3H(C14E3)] in aqueous solution and the interaction between them were studied by 1H self-diffusion coefficient, relaxation measurements and two-dimensional nuclear overhauser enhancement spectroscopy(2D NOESY). When pure anionic surfactant(STS) formed micelles, the α-CH2 groups were located on the surface layer of the hydrophobic micellar cores. The hydrophobic chains of STS are packed in the interior of the micellar cores. Pure nonionic surfactant(C14E3) formed large micelles in aqueous solution which is evidenced by the appearance of the small broad peaks of the protons on the hydrophobic chain of C 14E 3. 2D NOESY experiments give the evidence that mixed micelles are formed when STS and C14E3were mixed in aqueous solution. The relaxation measurement shows that α-CH2 and β-CH2 of STS and the α-CH2 and β-CH2 of C14E3locate on the surface layers of the mixed micellar cores. The hydrophilic moieties(CH2CH20)3 of the nonionic surfactant crimpe around the hydrophobic micellar cores. The self-diffusion coefficient measurement shows that the mixed micelles are larger than the pure micelles of STS. Softer and more incompact shells surrounding the micellar cores are created by the hydrophilic chains in C14E3micelles and STS/C14E3mixed micelles. The motion of the C14E3protons are more free in chloroform medium, but the appearance of weak cross peaks shown in the 2D NOESY map of this solution suggests that small self-aggregates may be formed.
    Quantum Chemistry Study on Stability and Reactivity of Reactive Intermediate of Starch Super-water-absorbent Resin
    YAN Li-Kai, LAN Ya-Qian, SU Zhong-Min, QIU Yong-Qing, SHAO Chen, LI Bao-Li,WANG Rong-Shun
    2003, 24(2):  297-300. 
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    The model geometries of reactive intermediates of the super-water-absorbent resin were determined by using ab inito UHF and density functional theory UB3LYP with 6-31G basis sets. The stability and reactivity of the two kinds of typical conformation isomers(1a, 1b and 2a, 2b) with their free radicals are obtained and analyzed. The calculation results show that the total energy of isomers 1a or 2b is lower. The energy gap of isomer 1a is smaller comparing with the frontier molecular orbitals of four model systems. HOMO energy of 1a is higher, so it is easy to lose electrons. LUMO energy is lower and it is easy to receive electrons, which benefits the charge transfer. The spin density of free radical mostly concentrates on C2 or C3 and has no large diffusion. They are the key part of reactivity. The analysis to the complex with isomer 1a and acrylic acid molecule indicate that the polymerization reaction is easy to finish because of giving out heat.
    Adsorption and Reaction Behavior of F-T Co catalysts Supported by Chemically-modified Alumina
    ZHANG Jun-Ling, CHEN Jian-Gang, DONG Qing-Nian, REN Jie, SUN Yu-Han
    2003, 24(2):  301-304. 
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    The influence of chemically-modified alumina on the adsorption and reaction behavior of Co catalysts was investigated by in situ FTIR, TPSR and Fischer-Tropsch synthesis. The adsorption of CO was determined by the alumina support treated in acid/base media. For the Co catalyst supported onto the ammonia-modified alumina, more bridged-form CO appeared, while the linear-form CO for the acetic acid-modified alumina was dominant. The bridged-form CO mostly participated in CO hydrogenation. CO hydrogenation showed that the Co catalyst supported onto the ammonia-modified alumina favored to increase the catalytic activity and C5+ selectivity, and however, the Co catalyst supported onto the acetic acid-modified alumina suppressed the activity and the carbon chain growth.
    Comparative Studies on Thermal and Electrochemical Properties of Room-temperature Molten Salt Electrolytes Based on LiTFSI with Urea and Its Derivatives
    LIANG Hong-Ying, WU Feng, CHEN Li-Quan, HUANG Xue-Jie
    2003, 24(2):  305-309. 
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    Thermal and electrochemical properties of new room-temperature molten salt electrolytes based on LiTFSI with urea and its derivatives have been studied. These electrolytes appear as liquid at room temperature though they are composed of two solids. DSC analysis shows that the eutectic temperature of LiTFSI and methylurea is about-38 ℃, lower than those of LiTFSI-urea and LiTFSI-1,3-dimethylurea. The conduction behavior of these electrolytes has been evaluated by AC impedance spectroscopy. With increasing numbers of methyl of urea, the conductivities of these room-temperature molten salt electrolytes decrease accordingly. The conductivity of LiTFSI/urea eutectic compound is 1.74×10-4 S/cm at 25 ℃ and 1.24×10-3 S/cm at 50 ℃.
    The Ab initio Study of Luminescent Mechanism for Dinuclear Complex,[Y+]2[Au(i-mnt)]2(Y+=[n-Bu4N]+,K+,[Ph4As]+)
    PAN Qing-Jiang, ZHANG Hong-Xing
    2003, 24(2):  310-314. 
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    The structures of [Au(i-mnt)]22- (i-mnt=i-marononitriledithiolate) were optimized by the ab initio MP2 and CIS methods for the ground state and excited state respectively. The calculated ground-state Au(Ⅰ)-Au(Ⅰ) distance of 0.282 5 nm indicates a weak attraction between the two metallic Au(Ⅰ) atoms. The IPCM(Isodensity Polarized Continuum Model) approach in the SCRF (Self-Consistent Reaction Field) method was employed to account for the solvent effect of the acetonitrile solvent, and the electronic structures, electronic absorption and emission of [Au(i-mnt)]22- in acetonitrile were obtained by the CIS calculations. The calculated absorption maximum, 315.5 nm, with the oscillator strength of 1.391 is assigned as an intraligand charge transfer(ILCT) transition. The phosphorescence with the wavelength of 436.2 nm arising from B3Au→1Ag is attributed to ILCT and metal to ligand charge transfer (MLCT) transitions, comparable to the emissive band around 500 nm of [n-Bu4N]2[Au(i-mnt)]2 in glass acetonitrile solution at 20 K in the experiment. Such a transition is described as an organ-ligand luminescent mechanism with metal decoration.
    Surface Enhanced Raman Scattering(SERS) Studies on the Interaction Between Self-assembled DNA and [Co(phen)3]2+/3+
    DONG Li-Qin, ZHOU Jian-Zhang, WU Ling-Ling, DONG Ping, LIN Zhong-Hua
    2003, 24(2):  315-319. 
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    The electrochemical in situ SERS study of the interaction between [Co(phen)3] 2+/3+ and ssDNA as well as dsDNA self-assembled on the gold substrate are conducted here for the first time, and the molecular-level information of interaction is obtained. In situ SERS spectroscopic evidence shows that [Co(phen)3] 2+/3+ binds dsDNA via both the intercalative mode into the A-T and G-C-rich regions and the electrostatic mode with [Co(phen)3] 2+/3+-PO2 interaction. A partial reduction of B-DNA structure of dsDNA in favor of A-DNA occurs upon [Co(phen)3] 2+/3+-dsDNA interaction. While [Co(phen)3] 2+/3+ binds ssDNA probably via electrostatic mode with [Co(phen)3] 2+/3+-backbone interaction.
    Oxygen Migration and Photocatalystic Activity of Pervoskite-type Oxides
    SANG Li-Xia, ZHONG Shun-He, FU Xi-Xian
    2003, 24(2):  320-323. 
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    The degradation experiments of water-soluble dye were carried out in the suspension systems of pervoskite-type oxides LaBO3(B=Fe, Co) prepared by citrate method, and the results show that photocatalytic activity is related with the mechanism of oxygen vacancies migration in the pervoskite-type structure which takes place along the anion octahedron edge, although not in linear fashion but via a curved path, resulting in a significantly lower energy barrier. In the photocatalytic oxidation reaction, electrons are trapped by oxygen vacancies at or near the surface and then form superoxide with adsorbed oxygen, which can make dye degrade rapidly. Oxygen vacancies in the pervoskite-type structure produced by oxygen migration act as electron traps and accordingly increase the amount of the absorbed oxygen on the surface.
    Spectroscopy Study on Photochromism of Salicylaldehyde-derived Schiff Bases
    ZHAO Jian-Zhang, ZHAO Bing, XU Wei-Qing, LIU Ju-Zheng
    2003, 24(2):  324-328. 
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    The photochromism of salicylaldehyde-derived Schiff bases were studied from a view-point of structure-property relationship. It was found that the π-conjugated system and the flexibility of the molecular skeleton play an important role in the determination of the photochromic behavior. The molecules with smaller π-conjugated systems or flexible skeletons are easy to undergo the photochromism.
    Combustion Energies of Hippuric Acid and Acetanilide
    AN Xu-Wu, HE Li-Lin, WU Shan-Xiang, HU Rong-Zu
    2003, 24(2):  329-331. 
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    A new precision rotating-bomb calorimeter has been built. It can be operated in the isoperibol or in the adiabatic mode. The data of the measured temperature could be collected automatically by a microcomputer and the result of determination could be calculated by using appropriate software. In the isoperibol mode, the apparatus was calibrated by using NBS39i benzoic acid with a standard deviation of the mean of ±0.006%. The combustion energies of hippuric acid and acetanilide have been determined to be -(23 542.7±0.9) J/g and-(31 245.8±2.4) J/g(mean and its standard deviation) respectively. The uncertainties of these results were estimated as twice the overall standard deviation of mean, to be ±4.5 J/g and ±7.5 J/g, respectively. These results are in agreement with the recommended values. The properties of the two compounds as the reference materials for combustion calorimetry concerning compounds containing C, H, O and N with a low nitrogen content have been discussed.
    Investigation of the Mechanism of CaCO3 Crystallization Controlled by Polymer Lattices P(St-co-MAA)
    CHEN Ya-Kun, ZHAO Ying, WANG Du-Jin, XU Yi-Zhuang, SHEN Qiang, WANG Jia-Jun, ZHENG Ai-Guo, WU Jin-Guang, XU Duan-Fu
    2003, 24(2):  332-334. 
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    In this paper, polymer latices P(St-co-MAA) were used to control the crystallization of CaCO3, and the influence of the lattices on the crystallization habit and morphology was studied by combination of XRD, FTIR and SEM. The mechanism of the morphology transformation of CaCO3 from calcite to vaterite with the increase of polar group content in latex was investigated. The concentrating effect of calcium ions on the latex surface inhibited the transformation from vaterite to calcite.
    Electronic Raman Bands of Neodymium and a New Mechanism for Raman Enhancement
    XU Yi-Zhuang, WU Jin-Guang, SUN Wen-Xiu, TAO Dong-Liang, SONG Zeng-Fu, WENG Shi-Fu, XU Zhen-Hua, XU Duan-Fu, XU Guang-Xian
    2003, 24(2):  335-336. 
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    Strong electronic Raman bands corresponding to the transition between 4I9/2 and 4I11/2 manifolds of Nd3+ are observed in the FT-Raman spectrum of neodymium complex because of the Raman enhancement effect. Neither resonant enhancement nor surface enhancement accounts for the Raman enhancement observed here. We propose a new mechanism of Raman enhancement(Feed-bach Raman Enhancement): the YAG laser excites the final state of Raman transition ( 4I11/2 of Nd3+) to the 4F3/2 state and causes a significant decrease of the population of Nd3+ at the 4I11/2 state. This renders the population ratio of Nd3+ at 4I9/2 and 4I11/2 deviates from the value required by the Boltzmann′s law. To restore equilibrium, Raman scattering is enhanced so that more Nd3+ ions are brought from 4I9/2 to 4I11/2. This hypothesis gets support from the temperature-variable FT-Raman spectroscopic results. Additionally, obvious differences between Stokes and Anti-stokes Raman spectrum of Nd3+ support our mechanism too.
    Studies on Nano-cobalt/Ethanol Sol Prepared by Pulsed Laser Ablation
    ZHANG Yi, CHEN Wen-Zhe, ZHANG Wen-Gong
    2003, 24(2):  337-339. 
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    A novel nano-cobalt/ethanol sol was firstly obtained by pulsed laser ablation on the interface of solid and flowing-liquid. TEM results show that nano-cobalt particles size is about 30 nm. Electronic diffraction and XRD analysis both indicate that the nano-cobalt is non-crystalline. It was found that the stretching vibration of associating hydroxyl(γOH) and the deformation vibration of C-H in ethanol are strengthened, but stretching vibration of γC-O in primary hydroxyl of ethanol is restrained through the FTIR spectrum. The UV-Vis results show that there are one strong absorption peak at 231.99 nm due to primary nano-cobalt particles and two medium absorption peaks at 273.00 and 308.56 nm due to quantum confine effect.
    Super-hydrophobicity of Post-like Aligned Carbon Nanotube Films
    LI Shu-Hong, FENG Lin, LI Huan-Jun, ZHAI Jin, SONG Yan-Lin, JIANG Lei, ZHU Dao-Ben
    2003, 24(2):  340-342. 
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    The post structure aligned carbon nanotube(ACNT) film was prepared by CVD. it was a ultra-hydrophobic film with a higher contact angle(166°) and lower sliding angle(less than 3°). The post structure ACNT film showed discrete pillar composed of carbon nanotubes, these pillar formed microstructure in the film, which affected both the contact angle and the sliding angle.
    Preparation of Electroluminescent Using Fluoride Pyrazoline
    LIANG Yu-Jun, JIN Ming, FU Lian-She, LU Ran, ZHANG Hong-Jie, ZHAO Ying-Ying
    2003, 24(2):  343-345. 
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    One fluoride tri-phenyl pyrazoline compound(FTPP) was synthesized. It showed an efficient photoluminescence(PL) ability to form a film. When FTPP was doped into poly(vinylcarbazole)(PVK) to form a film by spin-coating method, we found that the energy can be transferred from PVK to FTPP. Two types of organic eletroluminescent devices(OELDs) using PVK doping FTPP as emitting layer were fabricated, one was double layer device: ITO/PVK∶FTPP/PBD/Al and the other was three-layer device: ITO/PVK∶FTPP/PBD/Alq3/Al. 1,3,4-Oxadiazole derivative(PBD) was used both as electron-transporting layer and as hole-barrier layer. 8-Hydroxyquinoline aluminum (Alq3) was also used as electron-transporting layer. All devices could emit a blue light.
    Ring-opening Polymerization of Aliphatic Cyclic Esters by Using Organic Amino Calcium Catalyst
    PIAO Long-Hai , ZHANG Xin-Zhao, CHEN Xue-Si, DENG Ming-Xiao, JIANG Lian-Sheng, JING Xia-Bin 
    2003, 24(2):  346-349. 
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    ε-Caprolactone and L-lactide were ring-opening polymerized by using calcium catalysts treated with propylene oxide and acetonitrile/(propylene oxide). The influences of catalyst concentration and aging temperature, polymerization time and temperature on molecular weight of the polymers were studied. It was shown that this catalyst exhibited a high reactivity and some "quasi-living-polymerization" character and the molecular weight of the polyester could be controlled by adjusting the mass ratio of monomer to catalyst. Aging treatment of the catalyst and employment of the second organic modifier, acetonitrile, resulted in a higher molecular weight of the polymers. The highest molecular weight obtained was 270 000.
    FFT Algorithm for Calculating the SALS Patterns from Anisotropic Objects Immersed in an Isotropic Matrix
    HONG Ke, WANG TAO, ZHANG Hong-Dong, YANG Yu-Liang
    2003, 24(2):  350-354. 
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    In order to overcome the difficulties faced on analytically deriving the equation for describing the samll angle light scattering (SALS) patterns from anisotropic objects with arbitrarily director configurations, a Fast Fourior Transformation(FFT) algorithm for the calculation of SALS patterns from the anisotropic objects immersed in an isotropic matrix has been developed. With this method, the types of nematic droplets with different director configurations could be easily distinguished. For a certain configuration, it could also be achieved to indicate the direction of the main axis of droplets. It is fully demonstrated that the SALS patterns from the anisotropic objects can be predicted through the FFT algorithm without needs of complicated mathematical derivations.
    Synthesis, Characterization and Property of Poly(aryl ether amides) from 2-(4-Aminophenyl)-4-(3-methyl-4-aminophenoxy)-2,3-phthalazinone
    ZHU Xiu-Ling, JIAN Xi-Gao, LU Ye, WANG Rui-Ling, ZHANG Yuan-Hong
    2003, 24(2):  355-358. 
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    A novel aromatic diamine 2-(4-aminophenyl)-4-(3-methyl-4-aminophenoxy)-2,3-phthalazinone-1(1, DAMPP) containing aza heterocycle was synthesized in a higher yield starting from 4-(3-methyl-4-hydroxyphenyl)-2,3-phthalazinone-1(OM-HPPZ) via two steps conveniently. Diamine 1 polymerized with three aryl dicarboxylic acids to prepare a series of new aromatic polyamides in a high yield using Yamazaki phosphorylation method. The synthesized polymer has a high molecular weight with the inherent viscosity in the range of 0.40-0.60 dL/g. They exhibited high glass transition temperatures of 598-620 K and good thermostable properties with the 10% weight loss temperature above 673 K(in nitrogen). The range of their surface resistance coefficients is 5.89×1015-9.87×1015 Ω and the range of volume resistance coefficients is 1.39×1016-4.09×1016 Ω·cm. These polymers were readily soluble in polar solvents such as NMP, DMF and m-cresol etc, clear tough films were cast from their DMAc solutions. The structures of diamine 1 and polymers obtained was confirmed by MS, FTIR and 1HNMR, which are consistent with the designed structure.
    Physico-chemical Structure Characterizations of the Silk from Spider Selenocosmia as a Kind of Natural Nanometer Fiber
    HUA Jian, FAN Zhong-Yong, YANG Jian-Bin, PAN Gu-Ping, WU Da-Cheng
    2003, 24(2):  359-361. 
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    The physicochemical structures of silk from spider selenocosmia were characterized by means of IR, SEM and AFM. Based on the data of SEM and AFM, the diameters for the silk from spider selenocosmia were in the range of 100-500 nm, with the lower end of which this spider silk was considered as a kind of nanometer fibers. This silk from spider selenocosmia was much thinner than the silk from mulberry silkworm and the silk from spider nephila davipes, the diameters of which were 4 μm and 10～20 μm, respectively. Thus, the silk from spider selenocosmia could be considered as a natural nanometer fiber, which was rare in nature, especially in the form of a monofilament. It was shown from the results of IR spectra that the absorbance peaks of 1 644.73cm-1, called as the amide Ⅰ structure, were correlated with the "random coil" and alpha-helix conformations in the amorphous part. The absorbance peaks of 1 517.44cm-1, called as the amide Ⅱ structure, indicated B-sheet region plus a small amount of helical conformation existed. These molecular characterizations of silk from spider selenocosmia were similar to those of the silk from mulberry silkworm and the silk from spider Nephila davipes.
    Memory Effects for Depolarized Light Intensity and the Order in the Glassy PET
    BIAN Jie, YE Sheng-Rong, Lü Guang-Lie, FENG Lin-Xian
    2003, 24(2):  362-364. 
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    It was demonstrated that some level of order exists in glassy poly(ethylene terephthalate) by depolarized light intensity(DLI) technique, but this order is different from that in crystalline PET. The degree of order in glassy PET decrease with increasing temperature between 288-343 K. The active energy of this transition is about 22.56 kJ/mol. The IR analysis indicated that this order relates to gauche structure of the ethyleneglycol fragments. The decrease of order with temperature comes from the increase of distance between the order segments.
    Synthesis and Fluorescence Behavior of Acceptor-donor-acceptor Type Bismaleimides
    ZHANG Xin, JIN Ying-Hua, DU Fu-Sheng, LI Zi-Chen, LI Fu-Mian
    2003, 24(2):  365-367. 
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    Bismaleimides bearing electron-donating chromophore moieties, A(=)-D(*)-A(=) type monomers, i.e. N,N-bis(4-maleimidophenyl)methylamine (BMIPMA), N,N-bis(4-maleimidophenyl)aniline(BMIPA) and 2,5-bis(4-maleimido phenyl)-1,3,4-oxadiazole(BMIPODA) as well as their corresponding saturated model compounds, i.e. N,N-bis(4-succinimidophenyl)methylamine( BSIPMA), N,N-bis(4-succinimidophenyl)aniline(BSIPA) and 2,5-bis(4-succimidophenyl)-1,3,4-oxadiazole (BSIPODA) were synthesized. It was found that the fluorescence quantum yields of A(=)-D(*)-A(=) monomers were always dramatically lower than those of their corresponding saturated model compounds. These A(=)-D(*)-A(=) bismaleimides possess a strong SSQE, which is attributed to an intramolecular charge transfer interaction.
    Preparation of sPS/Montmorillonite Nanocomposites via Styrene Syndiotactic Polymerization with Metallocene
    ZHU Fang-Ming, ZENG Xi-Guo, HONG Xiao-Yun, LIN Shang-An
    2003, 24(2):  368-370. 
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    Novel syndiotactic polystyrene/montmorillonite nanocomposites were prepared via in situ intercalative coordination polymerization with Cp *Ti(OBz)3/MTN/MAO/TIBA catalytic system. The effect of polymerization conditions such as MTN/St mass ratio, temperature and monomer concentration on the styrene syndiospecific polymerization was investigated. The intercalation spacing in the nanocomposites as well as the exfoliation of the layer host was characterized with wide angle X-ray diffraction and transmission electron microscopy. The dispersibility of the nanoscale elemnets depended on the polymerization conditions and whether a surfactant is added or not into the montmorillonite.
    Self-assembly of Polystyrene-b-poly(ethylene oxide)-b-polystyrene Triblock Copolymer
    YUAN Jian-Jun, LI Ying-Shun, LI Xiao-Qin, ZHANG Xiao-Hong, CHENG Shi-Yuan, JIANG Lei, FENG Lin-Xian
    2003, 24(2):  371-373. 
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    In this paper, the self-assembly of PS43-b-PEO45-b-PS43 triblcok copolymer was investigated. The colloids were made by firstly dissolving the copolymer in the common solvents, including THF, 1,4-dioxane, and DMF, then droping water into the corresponding copolymer solution to induce the self-assembly. The aggregates prepared were characterized with TEM and AFM techniques. The experimental results demonstrated that the self-assembled vesicles were formed when THF and 1,4-dioxane were used as the common solvents to dissolve the copolymer, comparatively, using DMF as the common solvent resulted in the formation of spherical aggregates. The self-assembled aggregates observed, possessing hierarchical structures, could be used as either the nanostructures themselves for drug delivery systems, separations, catalysts, and so on, or templates or building blocks for more complex structures.
    Fluorescence Behavior of a β-Diketone-bridged Chromophore-containing Acrylic Monomer and Its Model Compound
    DU Fu-Sheng, ZHANG Xin, CHEN Guang-Qiang, LI Zi-Chen, LI Fu-Mian, PAN Hui, GAO Qing-Yu
    2003, 24(2):  374-376. 
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    A β-diketone-bridged chromophore-containing acrylic monomer, 1-(4-dimethylaminophenyl)-4-methyl-4-pentene-1,3-diketone(DMPDK) and its saturated model compound, 1-(4-dimethyl aminophenyl)-1,3-butanedione(DMBDK) were synthesized and investigated by spectroscopy. It was found that the fluorescence intensity of DMPDK was much lower than that of DMBDK at the same concentration, which indicates that DMPDK, a β-diketone-bridged acrylic monomer having chromophore moiety, also showed fluorescence structural self-quenching effect(SSQE). Photo-induced tautomerization of DMBDK in acetonitrile was studied by means of UV and fluorescence spectroscopy. The results imply that the fluorescence method is capable of monitoring tautomerization of some fluorescent β-diketones.
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