Mar 2007, Volume 2 Issue 1

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  • YANG Tao, NIU Li, LI Zhuang, DONG Shaojun
    The applications of scanning probe microscopy (SPM) in intrinsically conducting polymer research is briefly reviewed, including morphology observation, nanofabrication, microcosmic electrical property measurements, electrochemistry researches, in-situ measurements of film thickness change, and so on. At the same time, some important variations of SPM and the related techniques are briefly introduced. Finally, the future development of SPM in the study of intrinsically conducting polymers is prospected.
  • XIAO Dan, CUI Xiaowen, LI Weihua, YAN Deyue
    The Brill transition of even even polyamide 618 was investigated using differential scanning calorimetry (DSC), temperature-dependent wide angle X-ray diffraction (WAXD) and Fourier transform infrared (FTIR). The X-ray diffraction results indicate that the melt-crystallized sample of polyamide 618 transforms from the triclinic unit cell to the pseudo-hexagonal phase in the range of 120 180?C. In this range, the thermograph of polyamide 618 presents a broad endothermal peak. From the FTIR spectra, it was found that during the transition process of polyamide 618, the intensity of the intra-sheet hydrogen bonds becomes weak. At the same time, the CH2 amide bonds twist, and the all-trans conformation of methylene sequences is disordered by inserting the gauche conformation. The CH2 segments are in a mobile state because of the enhanced stretching and twisting vibrations of the C CO and C N bonds.
  • LIU Jiugui, JIANG Lizhong, ZHAN Jiayu, WU Dezhen, JIN Riguang
    A new route to porous polyimide (PI) films with pore sizes in the nanometer regime was developed. A polyamic acid (PAA)/polyurethane (PU) blend with PU as the disperse phase was first prepared via in situ polymerization of pyromelli
  • LIU Kaiyi, WANG Zhaoqun
    A preparation manner for monodispersed polystyrene (PS) nanoparticles polymerized by using a novel addition procedure of a monomer is suggested. In systems containing a smaller amount of surfactant compared with conventional micro
  • LIU Chunyan, JIN Zhaoguo, ZHANG Wengong
    Nanocarbon poly(methyl methacrylate) sols were prepared by pulsed laser ablation at the interface of target submerged in flowing liquid (PLA-IT/SFL) method, and the corresponding composite films were prepared by solution-casting.
  • XU Guofu, MOU Shenzhou, YIN Zhimin, ZHOU Lingping, LIAO Susan, CUI Fuzhai
    In this paper, a new polylactide (PLA)-based scaffold composite by biomimetic synthesis was designed. The novel composite mainly consists of nano-hydroxyapatite (n-HA), which is the main inorganic content in natural bone tissue fo
  • LIANG Xuezheng, GAO Shan, YANG Jianguo, LIU Caihua, YU Xinyu, HE Mingyuan
    The acetalization and ketalization of various aldehydes and ketones with catechol by using HY zeolite as catalyst were studied. Effect of the reaction time, mole ratio of reactants, and amount of catalyst on the yield of benzodi
  • LI Xiaoliu, DUAN Kefang, TIAN Jun, XU Xiaoming
    Five-membered azasugar derivatives with partially protected hydroxyl groups, and their fluorinated derivatives were synthesized via the key intermediates of norbornyl-like bicyclic acetals using D-xylose and D-glucose as starting
  • XU Yan, RAN Chunling, WANG Haixian, SONG Maoping
    Two novel ferrocenylphenyl-containing amides have been synthesized by reaction of ferrocenylbencarboxylchloride and 1, 2-di-(o-aminophenoxy)ethane. A single crystal X-ray analysis shows that compound 3 crystallizes in the
  • WANG Yunyan, CAI Yahua, YAN Chaoguo
    Dendritic p-t-butylcalix[n]arene amide derivatives with terminal amino groups of the first and second generations were synthesized by using divergent methods from ammonolysis of ethyl calixarylacetate with 1,6-diaminohexane and Michael addition of methyl acrylate. Their structures were confirmed by IR, 1H NMR. The recognition properties of these amide derivatives for several kinds of metal ions were studied with UV Vis spectroscopy. The results showed a great affinity for soft Ag+ and UO22+ ions and formed 1:2 or 1:3 stoichiometric complexes.
  • YAN Jinhong, ZHANG Cuiping, YANG Pin
    The inclusion complex formation of tanshinone IIA (Tan IIA) with hydroxypropyl-β-cyclodextrin (HPCD) was studied by using phase solubility method, and the formation constant for tanshinone IIA-HPCD- dextrin was determined. The effect of temperature on the reaction was studied through thermodynamics, and the changes inentropy, enthalpy, and free energy of the reaction were calculated. The molecular modeling provided further evidence for the formation of the inclusion complexes. Stable inclusion complex in solid state was characterized by IR spectra.
  • ZHOU Peng, MEI Hu, TIAN Feifei, WANG Jiaona, WU Shirong, LI Zhiliang
    Based on two-dimensional topological characters, a novel method called molecular electronegativity-interaction vector (MEIV) is proposed to parameterize molecular structures. Applying MEIV into quantitative structure-spectrometry relationship studies on ion mobility spectrometry collision cross-sections of 113 singly proto nated peptides, three models were strictly obtained, with correlative coefficient r and leave-one-out cross-validation q of 0.983, 0.979, 0.981, 0.979 and 0.980, 0.978, respectively. Thus, the MEIV is confirmed to be potent to structural characteri zations and property predictions for organic and biologic molecules.
  • LIN Li, ZHOU Yi, ZHU Yuexiang, XIE Youchang
    A series of carbon-covered titania (CCT) were prepared via pyrolysis of sucrose highly dispersed on titania surface in flowing N2. The samples were characterized by XRD, BET, DTA-TG, UV Vis, and their photocatalytic properties were evaluated with two model pollutants, methylene blue (MB) and rhodamine B (RB), at room temperature. The effect of carbon content on photocatalytic activity of the C/TiO2 composite was investigated. It was found that the effect of carbon content is different for different pollutants or different light sources. For three tested samples, under UV illumination CCT01 has the highest activity for MB photocatalytic degradation, while in the case of RB, CCT02 is the most active photocatalyst. Under visible light illumination, CCT005 has the highest activity for both MB and RB photocatalytic degradation.
  • SHI Xianying, WEI Junfa
    Three kinds of bis-quaternary ammonium salts of peroxotungstate and peroxomolybdate, such as PhCH2N-(CH2)6NCH2Ph[W(O2)4] ° 2H2O, PhCH2N(CH2)6NCH2Ph[WO(O2)2(C2O4)] and PhCH2N(CH2)6NCH2Ph [MoO(O2)2(C2O4)], have been synthesized and characterized. Their catalytic activity in the oxidation of cyclohexanol and benzyl alcohol was investigated with only aqueous 30% hydrogen peroxide. The results show that the bis-quaternary ammonium peroxotungstates are excellent catalysts in the oxidation of benzyl alcohol and cyclohexanol under moderate conditions. However, the catalytic ability of bis-quaternary ammonium peroxomolybadates is relatively poor. The yields of benzyl acid, benzaldehyde, and cyclohexanone reached up to 93.0%, 93.6%, and 91.7%, respectively.
  • CHEN Xing, CUI Dafu, LIU Changchun, LI Hui, ZHAO Weixing
    A sample pretreatment microfluidic chip was described based on the principle of solid phase extraction and micro electro mechanical system technology. Oxidized porous silicon with the large surface area as the solid phase matrix for absorption of DNA from a biological sample can greatly improve the DNA yield. The factors that could affect the DNA yield were analyzed and the preparation technology and the experiment procedure were improved. The DNA purification process from the rat peripheral blood can be achieved and the DNA yield is 24 ng/(?L whole blood), which can reach the level of the commercial DNA purification kits. Furthermore, the DNA extracted from the whole blood can be amplified by polymerase chain reaction, which can achieve a high efficiency of the amplification.
  • LI Shan, LIU Zhongfang, LIU Shaopu, KONG Ling
    When trypsin reacts with Herring sperm DNA (hsDNA), Salmon sperm DNA (sDNA), and Calf thymus DNA (ctDNA) to form a complex, the resonance Rayleigh scattering (RRS) was remarkably enhanced and new RRS spectra appear. These new spectra have similar characteristics of RRS spectra. The maximum RRS peaks are at 307 nm (hsDNA, sDNA) and 290 nm (ctDNA), and other peaks are at 350 nm. The scattering intensity is proportional to the concentration of DNA or trypsin; so this intereaction can be used to determine trypsin using DNA or DNA using trypsin. In the determination of DNA using trypsin, the linear ranges for hsDNA, sDNA, and ctDNA are 0 2.3, 0 2.5, and 0 1.9 µg " mL-1, and the detection limits are 0.4, 0.7, and 1.1 ng " mL-1, respectively. In the determination of trypsin using hsDNA, the linear range is 0 30.0 µg " mL-1, and the detection limit is 39.0 ng°mL-1. In this paper, the intereaction conditions were optimized. The affecting factors, chemical properties of the complex, and the composition ratio of trypsin with DNA were investigated. Using trypsin as RRS probe, a sensitive method for the determination of trace amounts of DNA was developed.
  • LI Gang, JIN Tongshun, YOU Juan, WANG Lu, WU Qinan
    The phases, chemical composition, surface appearance, crystal size, specific surface and thermal behavior of the unprepared and calcined forms of the mineral Magnetitum (Cishi), used as Chinese traditional medicine, were characterized by using X-ray powder diffraction, scan electron microscopy, inductively coupled plasma-atomic emission spectometry (ICP) and thermogravimetric (TG). The results indicated that after calcination the main phase Fe3O4 of the calcined Magnetitum (Duan Cishi) remained, while the Fe2O3 phase disappeared. The contents of the harmful chemical elements Cd and Pb were obviously reduced, while the crystal size increased from 24.5 to 35.7 nm and surface loosened. There were different TG curves for unprepared and calcined Magnetitum (Cishi) samples on heating. The former showed two weight-losing steps (at 367.9-422.1?C and 568.8-594.1?C), and the latter only one. These results might serve as a base for quality evaluation of Magnetitum (Cishi).
  • ZHAO Pengcheng, WANG Yanji, XU Yuanyuan, YAO Lijuan
    The analysis of roller pen inks has become more and more important in fraudulent document examination because of the extensive use of roller pens in financial documents. Capillary electrophoresis with powerful resolution was applied for the analysis of roller pen inks. The experiment focused on the optimization of the separation of the extract from commercially available roller pen entries. A better separation electropherogram was obtained when a 20 mM borate buffer at pH 8.5 and a fused silica capillary with an inner diameter of 100 µm with a total length of 47 (40 cm to the detector window) were used. Five inks from roller pens of different manufacturers and countries were analyzed, and their electropherograms showed that most patterns are distinctly different from each other. Capillary with inner diameter of 100 µm increased the intensity of determination; therefore, color dyes were identified in the visible range and were able to provide more information for comparing types of roller pen inks.
  • ZHANG Baoli, XING Yongheng, ZHANG Yuanhong, BAI Fengying, XU Jiqing, YANG Guangdi, HUANG Xiaoying
    Two Mo/S complexes: K6[Mo2O2S2(C2O4)2-(ClPO3)2]°H2O (1) and K6[Mo2O3S(C2O4)2(ClPO3)2]°3H2O (2) containing oxalate ligand were prepared by the reaction of (NH4)2MoS4 and potassium oxalate by adding a small amount of H3PO4 to adjust the value of pH in the system of methanol and water under an atmosphere of pure nitrogen at ambient temperature and characterized by means of elemental analysis, IR, and UV-Vis. Results of the analysis reveal that crystals of the complex 1 are orthorhombic, space group Pbcn, a=4.6370(2) nm, b=0.7549(2) nm, c=1.3888(4) nm, V=4.861(2) nm3, Z=8, M=945.49, Dc=2.58 g/cm3, μ=2.625 cm-1, R=0.063, and wR=0.075. In addition, their spectral properties were also discussed.
  • ZANG Jinxin, ZHAO Gaoling, HAN Gaorong
    CdS nanoparticles with good crystallinity were prepared by hydrothermal method in microemulsion composed of polyoxyethylene laurylether/water/cyclohexane/butanol. The structure and the size of the CdS nanoparticles were analyzed by TEM and XRD. The UV Vis optical absorption of the samples was also investigated. The results show that hydrothermal treatment is an effective method to prepare CdS nanoparticles of hexagonal structure at lower temperature. The particles were in dimensional uniformity. The diameter of the CdS nanoparticles decreased with the increase of the molar ratio of water to surfactant. The minimum diameter of the CdS nanoparticles prepared in this work was about 10 nm. Obvious blue shift appeared in the UV Vis absorption spectra.
  • ZHU Wen, YANG Junyou, GAO Xianhui, HOU Jie, BAO Siqian, FAN Xian
    Thin-layer electrochemical studies of the underpotential deposition (UPD) of Bi and Te on cold rolled silver substrate have been performed. The voltammetric analysis of underpotential shift demonstrates that the initial Te UPD on Bi-covered Ag and Bi UPD on Te-covered Ag fitted UPD dynamics mechanism. A thin film of bismuth telluride was formed by alternately depositing Te and Bi via an automated flow deposition system. X-ray diffraction indicated the deposits of Bi2Te3. Energy Dispersive X-ray Detector quantitative analysis gave a 2: 3 stoichiometric ratio of Bi to Te, which was consistent with X-ray Diffraction results. Electron probe microanalysis of the deposits showed a network structure that results from the surface defects of the cold rolled Ag substrate and the lattice mismatch between substrate and deposit.