Table of Content

10 June 2005, Volume 26 Issue 6

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Articles

Studies on Subacute Biochemical Effects of Aristolochic Acid Using ¹H NMR Spectroscopy Combined with Pattern Recognition

ZHANG Xiao-Yu, WU Hui-Feng, PEI Feng-Kui, NI Jia-Zuan

2005, 26(6):  991-996. 

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¹HNMR spectroscopy and pattern recognition method were used to the studies on the subacute biochemical effects of aristolochic acid(AA). Male Wistar rats were intraperitoneal with AA for 5 days. Urine samples were collected after being treated with AA and the NMR spectra show the NMR marker related to renal papillary and proximal tubular lesion changed greatly. Urine samples from the rats treated with model toxins sodium chromate, mercury Ⅱ chloride, 2-bromoethanamine hydrobromide, α-naphthylisothiocyanate and hydrazine(NaCrO₄, HgCl₂, BEA, ANIT and HYD) were collected over a 48 h time course. Each NMR spectrum was data-processed and analyzed by PCA methods. A successful classification of the toxicity and biochemical effects of AA was achieved. The biochemical effects and PCA classification indicate that the renal toxicity of AA was a progressive course with the accumulation of AA, and caused widespread lesion to kidney including proximal tubule and papillary necrosis. The lesion is irreversible. This method can be used in the toxicological study of other drugs.

Synthesis and Characterization of Water-soluble Zinc Porphyrin Complex and Its Interaction with CT DNA

KANG Jing-Wan, WU Hai-Xia, LU Xiao-Quan, SU Bi-Quan, ZHOU Lin

2005, 26(6):  997-1001. 

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A porphyrin 5,10,15,20-tetrakisporphyrin and its Zn complex(TPPBr(Zn)) were synthesized and characterized. The interaction of TPPBr(Zn) with CT DNA was studied by UV-Vis spectroscopy, fluorescence spectra, circular dichroic spectrum and viscosity measurements. The constant of TPPBr(Zn) binding to CT DNA is 2.64×10⁵ L/mol. The results suggest that the porphyrin complex can bind to DNA by self-stacked outside binding and static binding.

Fabrication of Carbon/Carbon Composites by Chemical Liquid-vaporizedDeposition with Toluene as Precursors

WANG Lan-Ying, LI He-Jun, LU Jin-Hua, BAI Rui-Cheng, GUO Ling-Jun, ZHANG Xiu-Lian

2005, 26(6):  1002-1005. 

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Carbon-carbon composites with a density of 1.63 g/cm³ were prepared by chemical liquid vaporized deposition with toluene as the precursors and stratum carbon-cloth as the preform at 950 ℃ in 9 hours. Its microstructure, X-ray diffraction and mechanical properties were measured. The results indicate that the homogeneous materials can be prepared by chemical liquid vaporized deposition using toluene as the precursors. The ingredient of the recovered toluene was also analyzed with GC/MS. The possible mechanism of initial pyrolysis and polymeric process of toluene was discussed.

Phase Diagrams of Microemulsion Systems and Its Application to the Synthesis of Fluoride Nanoparticles

YAN Jing-Hui, ZHANG Ming, LIAN Hong-Zhou, YE Ze-Ren, SHI Chun-Shan

2005, 26(6):  1006-1009. 

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Pseudo-ternary phase diagrams in quaternary microemulsion systems of cetyltrimethyl ammonium bromide(CTAB), n-butanol, n-octane and wateror NH₄F solution, or Ba(NO₃)₂ solution, KNO₃-Mg(NO₃)₂ mixture solution are presented. Variation of the electrical conductivity with the change of water content(or solution) was observed, which supported the phase behavior of microemulsion systems. KMgF₃ nanoparticles were prepared with the optimal parameter of phase diagrams of microemulsions systems.

Synthesis of High Ordered SiO₂ Microwires with Bamboo Charcoals as the Template

QIU Jin, YANG Ru, JIANG Nan, LI Min

2005, 26(6):  1010-1013. 

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The microstructrue of bamboo charcoal was studied through SEM and highly ordered SiO₂ microwires array were synthesized by using sol-gel method with TEOS as the Si resource and bamboo charcoal as the template. SEM, EDX and XRD techniques were used to characterize the products. The results show that the products were highly pure cristobalite SiO₂ microwires with the diameter of 1-2 μm and length over 200 μm, which copied to the structure of micropore precisely. It shows that the micropores of the bamboo charcoal may perform main template function.

Novel Potential Myocardial Perfusion Imaging Agent ^99mTcN(PNP5)(NOEt)]⁺

CHU Jin-Feng, LI Bin, KONG De-Jing, WANG Xue-Bin, ZHANG Jun-Bo, WANG Jin-Cheng, MI Hong-Zhi, ZHAO Jian-Dong

2005, 26(6):  1014-1017. 

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[^99mTcN(PNP5)(NOEt)]⁺was prepared through ligand exchange reaction and its radiochemical purity was over 90% measured by TLC and HPLC. The results of charge character and stability studies indicate that [^99mTcN(PNP5)(NOEt)]⁺ is a cation with a good stability. Studies on the biodistribution in mice and SPECT imaging in dog show that ^99mTcN(PNP5)(NOEt)]⁺ possessed a high myocardial uptake and good retention, and high target to non-target ratios, suggesting that it may be a potential myocardial perfusion imaging agent.

Preparation of Hollow Spheres of Si/Al Composite Oxide with Mesopores in the Shell Wall

JIANG Yan-Qiu, LIU Yan-Hua, ZHAO Xu, ZHAO Jing-Zhe, TIAN Yu-Mei, WANG Zi-Chen

2005, 26(6):  1018-1020. 

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Hollow spheres of Si/Al composite oxide with mesopores in the shell wall were prepared by combining O/W/O emulsion with sol-gel process. In this study, TEOS and aluminum isopropylate were used as silicon resource and aluminum resource, respectively. As an additive, PEG-20000 was added into the inorganic precursors. TEM and N₂ adsorption-desorption isotherms indicate the presence of mesopores with uniform pore size in the shell wall. The diameter, shell thickness and hollow structure property of the spheres were characterized by transmission polarized light microscopy and SEM. ²⁷Al MAS NMR spectrum shows that the coordinated number of the aluminum species is four. The influences on special morphology under different oil phase and reaction temperature were also investigated. The hollow spheres exhibit high thermal stability and can remain their intact spherical structures even after calcination at 550 ℃ for 6 h. This strategy can be extended to synthesize hollow spheres of other binary composite oxide with mesopores.

Synthesis and Structure of a Novel Cage-like Rare Earth Complex [La₂(TCM)₂(DMF)₆]·2DMF

CAI Zheng-Hong, TANG Jing, TANG Yu, TAN Min-Yu, YU Kai-Bei

2005, 26(6):  1021-1023. 

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A new tripod polyaromatic acid ligand H₃TCM(H₃TCM=2,4,6-tris₁,3,5-trimethylbenzene) and its binuclear rare earth complex ·2DMF were prepared and the structure of complex was characterized by single crystal X-ray diffraction. The complex crystallizes in triclinic crystal system, space group P1 with a=1.123 3(2) nm, b=1.374 1(2) nm, (c=)1.731 8(2) nm, α=78.19(1)°, β=80.02(1)°, γ=80.08(1)°, V=2.550 8(7) nm³, Z=1, (R=)0.035 8, wR=0.080 3. Two TCM ligands that are both in cis, cis, cis-conformations adopt face-to-face orientation and are joined together by two La³⁺ to a novel binuclear cage-like structure. Two DMF molecules are encapsulated in this cage by coordination. In addition, the other two free DMF molecules are embedded in the channels from the packing of these units along a and b axises.

Synthesis of SmPO₄ Nanorods by Microemulsion-assisted Solvothermal Method

HE Xiao-Yan, CAO Min-Hua, WU Xing-Long, HU Chang-Wen,

2005, 26(6):  1024-1026. 

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SmPO₄ nanorods were synthesized by a microemulsion system containing water, cetyltrimethylammonium bromide(CTAB), cyclohexane, and n-pentanol. Transmission electron microscopy(TEM) was used to characterize the shape and size of the as-synthesized sample. It was found that ω(molar ratio of water to surfactant) and reactant concentration play an important role in the formation of SmPO₄ nanostructures.

Hydrothermal Synthesis and Characterization of a New Layered Fluoroaluminophosphate [C₄H₁₂N₂][Al₂(PO₄)₂(H₂O)₂F₂]

WANG Mei, LI Ji-Yang, LI Yi, SONG Xiao-Wei, YU Ji-Hong, XU Ru-Ren

2005, 26(6):  1027-1029. 

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A new layered fluoroaluminophosphate Al₂(PO₄)₂(H₂O)₂F₂(compound Ⅰ) was synthesized hydrothermally. It crystallizes in the monoclinic space group P2₁/c with a=1.102 40(7) nm, (b=0.695 51(4) nm,) c=0.928 05(5) nm, β=111.027(3)°, Z=6, R₁=0.037 9, wR₂=0.079 2(all data). Its structure contains Al₂(PO₄)₂(H₂O)₂F₂^2- macroanonic sheets built up from PO₃(O) tetrahedra and AlO₃F₂(H₂O) octahedra to form three-, four-, six-membered ring-net stacked sheets in an AAAA sequence along direction. The sheets are held together by diprotonated piperazine cations decomposed from 1-methylpiperazine through extensive hydrogen bonds.

Preparation and Properties of Fluorescent Self-assembled Bilayer Membrane

SUN Xiang-Ying, WENG Wen-Ting

2005, 26(6):  1030-1034. 

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Fluorescent reagent 2-(1-naphthyl)aminoacetic acid(NAA) was assembled onto the gold surface via its electrostatic interaction with DL-cysteine(Cys) that was directly assembled on the gold surface via Au_S bond. Strong fluorescence was observed from the NAA self-assembled bilayer membrane on the gold surface and was highly efficiently quenched by Cu²⁺ that was allowed for an extremely highly sensitive detection of Cu²⁺ with a detection limit of 7.87×10^-11 mol/L. The fluorescence from NAA/Cys/Au can be easily the regenerated and therefore the present report showed a reusable method for immobilizing reagent in fabricating fluorescent chemosensors. The self-assembled monolayer and bilayer were primarily characterized by electrochemical method and electron energy spectrum. The electrochemical behavior of the SAMs on the gold electrode in the solution of (K₃)/K₄ was investigated by cyclic voltammetry and AC impedance spectroscopy. The result of the experiment shows that Cys/Au has an excellent pinhole property to enhance the interfacial electron transfer, when the NAA was assembled onto the electrode the pinhole-free properties block the interfacial electron transfer from redox couple in the solution to the substrate.

Real-time Characterization and Quantitative Detection of Cytochrome c Based on SAMs with Electrochemical Quartz Crystal Microbalance

LI Jin-Hua, HU Jin-Bo, LI Qi-Long

2005, 26(6):  1035-1038. 

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Electrochemical quartz crystal microbalance(EQCM), which is capable of sensitive measurement for mass and electrochemical signals, was employed to study cytochrome c. Self-assembled monolays(SAMs) with carboxy groups were first coated on the gold electrode of a quartz crystal resonator by adsorption of ω-mercaptoundecanoic acid(MUA), cytochrome c was then covalently attached to the surface via N-ethyl-N'- carbodiimide hydrochloride(EDC) and N-hydroxysuccinimide(NHS). The processes for self-assembly of MUA and immobilization of cytochrome c were both real-time characterized. And the surface coverage densities of MUA and cytochrome c were estimated to be 3.73×10^-9 and 7.31×10^-11 mol/cm², respectively. The amount of cytochrome c was found to be proportional to the frequency changes between 0.03 μmol/L and 3.0 μmol/L, with a regression equation Δf(Hz)=50.19 c(Cyt C)+67.07(r²=0.998), and the limit of detection of 1.19×10^-9 mol/L was also attained.

Resolution of Noisy HPLC-DAD Data by Two-dimensional Wavelet Transform and Subwindow Factor Analysis

DONG Lin, XU Lu

2005, 26(6):  1039-1042. 

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Integrated two-dimensional(2D) wavelet transform and subwindow factor analysis was used for the resolution of simulated HPLC-DAD data containing high level noise. At first, the 2D wavelet transform was performed for filtering the noise. Then, the subwindow factor analysis method was carried out for the resolution of the overlapping peaks. The results show that the noise can be filtered when S/N ratio is equal to 10.

Tagging Cells with Quantum Dots by Electroporation

YANG Rui, JI Wei, YAN Yu-Xi, SHI Yan-Yu, FEI Qiang, MU Ying, JIN Qin-Han

2005, 26(6):  1043-1045. 

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An electroporation method was proposed to make QDs pass through the membranes of K562 leukaemia cells. This method is operated simply and facilitates the tagging experiment greatly. The results show that when the electroporation voltage is 200 V and the lasting time is 1 ms, a high tagging rate is reached. A lot of cells can be tagged at the same time and the livability of the cells is 60%. The whole process can be completed in 20 min. This method brings forward some more extrusive advantages than cell endocytosis and microinjection method, and there should have a very good foreground for further applications.

Identification of Soluble Resistance-related Calcium Binding Protein by Bio-mass Spectrometric Analysis

LIU Ning, QI Jing, LV Lei, LIU Zhi-Qiang, LIU Shu-Ying, YANG Chun-Zheng

2005, 26(6):  1046-1048. 

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The protein profiles of the drug-resistant cell line K562/A02 and its sensitive parental cell line K562 were compared by using high resolution two-dimensional gel electrophoresis with IPG strip of pH 4.7-59. One protein spot was found to be differentially expressed, which was identified as the soluble resistance-related calcium binding protein(sorcin). Tandem mass spectrometric analysis of one tryptic peptide by a TOF-TOF analyzer as well as the western blot analysis substantiates the result derived from peptide mapping fingerprint data.

Detection of Cinchonine Using Molecularly Imprinted Electrosynthesized Polymer as Biomimetic Receptor Layers

LIU Zhi-Hang, HUAN Shuang-Yan, SHEN Guo-Li, YU Ru-Qin

2005, 26(6):  1049-1051. 

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An attempt was made to combine molecular imprinting technique and the electropolymerization of self-assembled o-amino thiophenol(o-AT) to prepare imprinted film using cinchonine as the model template analyte. The procedure of forming recognition cavity and the effect of the ratio of monomers to templates on the imprinted film, together with sensitivity and selectivity to cinchonine on the imprinted electrode, were demonstrated. An indirect and rapid detection was carried out using potassium ferricyande as a probe. Stable response is achieved within 4 min, covering a linear range (5.0×10^-6)₄.0×10^-5 mol/L. From the results, the main driving force for recognition is supposed to be hydrophobic interaction, complementary cavity effect and phenyl group for π-π interactions with the enaphthyl residue.

A Novel Non-invasive Method of Blood Glucose MeasurementUsing FT-Mid-IR Spectroscopy

ZHAO Ying, ZHANG Yuan-Fu, YANG Li-Min, XU Yi-Zhuang, WENG Shi-Fu, YANG Zhan-Lan, WU Hui-Zhong, ZHOU Wei-Jin, XU Duan-Fu, WU Jin-Guang

2005, 26(6):  1052-1054. 

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The blood glucose concentrations of volunteers from diabetes patients and healthy adults(all patients and volunteer who joined this experiment gave their consents) were measured by using a modified WQF-200 FTIR spectrometer with a newly designed ATR accessory. The results of this method are in good agreement with the clinical blood detection. The determination basis for this technique from the physiological point of view are also discussed based on the experimental results, which indicated that the glucose components measured by the FT-Mid-IR-ATR are from the secretions on the skin and glucose components within the body. The glucose components in both sources exhibit a linear relationship with blood glucose concentration within the body. All the results demonstrated that blood glucose concentration can be measured in a convenient, rapid and non-invasive way using ATR-FTIR spectroscopy, which is suitable for developing of a new technique to monitor the continuous variation of blood glucose concentration of diabetes patients in real time.

Electrochemical Behaviour of the Interaction Between Chitosan and Alizarin

TAN Xue-Cai, MAI Zhi-Bin, ZOU Xiao-Yong, QIU Jun-Ming, CAI Pei-Xiang

2005, 26(6):  1055-1057. 

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The interaction between Alizarin red(AR) and Chitosan(CS) was investigated in (0.1 mol/L) HAc-NaAc buffer solution(pH=4.5) on the glassy carbon electrode(GC) by cyclic and square wave voltammetry. The results show that both AR and AR-CS complex have a well-defined quasi-reversible redox wave(V_pc=-0.46 V, V_pa=-0.41 V) with adsorption characteristics. Electron transfer coefficient(α) and reaction rate constant(K_s) of AR and AR-CS were measured by cyclic voltammetry. The maximum binding numbers m between AR and CS was found to be 2 500. The experiment results confirmed that lower concentration of CS can enhance the detection sensitivity, while higher concentration of CS can lower the detection sensitivity. In the presence of 2.0×10^-5 mol/L AR, the peak current of system are proportional to CS concentration in the range of 1.25×10^-8～2.5×10^-7 mol/L, and inversely proportional to CS concentration in the range of 2.5×10^-7～1.25×10^-5 mol/L, respectively. The binding interaction mechanism was also discussed.

Synthesis and Hill Inhibitory Activity of 2-Cyano-3-methylthiobenzyl Acrylates

GAO Ying, CHEN Xiao-Fang, LIU Bin, ZOU Xiao-Mao, HU Fang-Zhong, YANG Hua-Zheng

2005, 26(6):  1058-1061. 

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Acrylates are important PSⅡ inhibitors, which always have high herbicidal activities. Based on target's structure, bio-rational molecular design and our previous studies, the title compounds were synthesized. All compounds were structurally confirmed by ¹H NMR, elemental analysis and IR. The Hill reaction inhibitory activity of them was tested and the results indicated that some showed the moderate inhibitory activity, in the result of that the benzene ring reduced the electron density of the β-oxygen atom in the ester chain, and hindered the better interaction between it and (Ser 268.) The relationship between the structure and activity was analyzed, which indicated the substituents on the benzene ring have influence on the activities.

Modification of Bis(pyrazol-1-yl)methanes with Organotin and Their Reactions with W(CO)₅THF

ZHAO Shu-Bin, WEN Zhen-Kang, WANG Ji-Tao, TANG Liang-Fu

2005, 26(6):  1062-1066. 

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The modification of bis(pyrazol-1-yl)methanes by substitution of organotin groups on the methine carbon was carried out by the reaction of bis(pyrazol-1-yl)methyllithium(LiCHPz₂) with organotin halide(R₃SnX), yielding a series of R₃SnCHPz(R=alkyl or aryl; Pz=substituted pyrazole) ligands. Upon the treatment of these ligands with W(CO)₅THF, they displayed versatile reactivities, depending on the properties of substitutions on the tin atom. The reaction of Ar₃SnCHPz₂ with (W(CO)₅THF) resulted in the oxidative addition of the tin-carbon(sp³) bond to the tungsten(0) center, while the similar reaction of Bz₃SnCHP_z2(Bz=benzyl; Pz=3,5-dimethylpyrazole) only gave decarbonylation complex of (Bz₃Sn)(CHP_z2W(CO)₄). In addition, the reactions of Ph₂BzSnCHPz₂ and (PhMe₂CCH₂)₃SnCHPz₂ with (W(CO)₅THF) resulted in the partial decomposition of ligands to yield CH₂Pz₂W(CO)₄ and , with the loss of organotin groups.

Synthesis of 5-Amido-1H-imidazopyridine Derivatives and Their AngiotensinⅡ Receptor Antagonistic Activities

XU Jin-Yi, HUA Wei-Yi, WU Xiao-Ming, WANG Qiu-Juan, HU Song

2005, 26(6):  1067-1071. 

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AngiotensinⅡ(AⅡ) receptor antagonists are clinically useful for the management of cardiovascular disease. Based on the analysis of the quantitative structure-activity relationships of forty-two new compounds reported in literatures as AⅡ receptor antagonists, a series of novel 5-amido-1H-imidazopyridine derivatives were designed and synthesized by application of the methods of computer aided drug design and principles of bioisosterism and hybridization. All of them were first reported and their structures were confirmed by IR, ¹H NMR and MS spectra. The results of preliminary pharmacological tests in vitro show that some target compounds have certain antagonistic activity of AⅡ receptor. Moreover, the analysis of SAR suggests that N-phenylpyrrole-2-tetrazole can be used as a substitution for future designing of novel AⅡreceptor antagonists.

Stereoselective Synthesis of(5Z,7E)-Dodecadien-1-ol

TAO Yun-Hai, CHENG Wei-Xian, ZHANG Yu-Shun, GU Kun,

2005, 26(6):  1072-1075. 

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Sexpheromone of Dendrolimus Spp. is composed of (5Z, 7E)-5,7-Dodecadien-1-ol(1) and its acetate and propionate. At first 7-bromo-(4Z, 6E)-heptadien-1-al(2) was stereoselectively synthesized by the tandem addition reaction of acrolein with acetylene in the presence of Pd(OAc)₂. Novel stereoselective synthesis of (5Z, 7E)-5,7-Dodecadien-1-ol was achieved in five steps, using palladium-catalyzed coupling reaction of 7-bromo-(4Z, 6E)-4,6-heptadiene-1-al ethylene acetal from production of the above aldehyde with Grignard reagent as the key step. The structures of all the compounds were confirmed by IR, NMR and MS spectra.

Effects of Different Leader Peptides on the Foreign Peptide Displayed on Gene 8 Protein of Filamentous Phage

WANG Li, HUA Pan-Yu, GAO Rui-Juan, YANG Qiong, SONG Jin-Na

2005, 26(6):  1076-1080. 

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Phage Display Technique was developed in 1985, it were applied in various biological fields. Phage can be exploited to display peptides, protein domains and even whole protein on its surface. Gene 3 protein and gene 8 protein are both the coat proteins of filamentous bacteriophage. Both of them were synthesized by using the precursors(pre-coats). Through different transmembrane pathways, they were inserted into the inner membrane of Escherichia coli cell and cleaved into mature proteins by the leader peptidase. To investigate the importance of the leader peptides, a small peptide was incorporated into the N-terminal region of gene 8 protein by using gene engineering methods. And for the first time, the leader peptide was deleted or replaced with the leader peptide of gene 3 protein. Pulse-chase analysis demonstrates the effects of different leader peptides on the polypeptide displayed on the N-terminal of gene 8 protein. The results showed that the precursor couldn't be converted into mature coat protein without the aid of leader peptide, while the leader peptide of gene 3 protein made gene 8 protein containing a foreign peptide become mature protein. These results have an important significance for the further studies of transmembrane mechanism of coat proteins of filamentous bacteriophage in E. coli.

Synthesis, Crystal Structure and Electrochemical Properties of Two Novel Diferrocenyl Thiourea Derivatives FcL₁ And FcL₂

XU Yan, WANG Fei, FU Yong, ZHANG Qiao-Hong, YE Bao-Xian, SONG Mao-Ping, WU Yang-Jie

2005, 26(6):  1081-1085. 

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Two novel diferrocenyl thiourea derivatives FcL₁ and FcL₂ were synthesized. The structures of the compounds were determined by elemental analysis, IR and ¹H NMR spectra. The X-ray single crystal structure analysis of FcL₁ indicates that the crystal belongs to triclinic system, P1 space group, there was a hydrogen bond in the compound. It was found that the electrochemical property of FcL₁ was very similar with that of FcL₂, the redox couple(FcL₁: E_1/2=600 mV; FcL₂: E_1/2=605 mV) was corresponding to the progress of 2Fc³⁺+2e^-2Fc²⁺, which can be rationalized by the equivalent environment of the ferrocene subunit in each case. The difference between m-ferrocenylaniline and p-ferrocenylaniline didn't cause the distinct change for their diffusion coefficient(D), but caused the distinct change for their electrochemical reaction rate constant(k_s).

Self-assembly of Biphenyl-bridged and Amino Acid-based Macrocycle Compounds

GUO Wei, MI Xue-Ling, WANG Jing, HE Jia-Qi, CHENG Jin-Pei

2005, 26(6):  1086-1089. 

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As part of our efforts aimed at developing molecular receptors and peptide conformational templates, we have conducted a research on design, synthesis, and application of structurally modified cyclopeptides. In this paper, we disigned and synthesized three biphenyl-bridged, amino acid-based macrocycles. The investigation of crystallograghic structures reveals that in the solid state, these macrocycles were assembled into twin-tube, 3D network and chain-like supramolecular structures, respectively, in which the C-H...O hydrogen-bonds play important roles. These findings may be helpful for understanding the role of the C-H...O hydrogen bonding in determining crystal packing, molecular recognition, and the structural stability of biological macromolecules.

Purification of Epididymis-specific Protein from Porcine Seminal Plasmas and Its Primary Structure

QIU Fang-Ping, DU Pei-Ge, AN Li-Ping, LV Gang, LI Qing-Shan

2005, 26(6):  1090-1092. 

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Through successive chromatography on Q-sepharose, Matrex Red A, Superdex S-200 and Resource Q chromatography column, epididymis-specific protein from porcine seminal plasma was purified. Epididymis-specific protein(PE4) was purified to homogeneity by polyacrylamide gel electrophoresis. The molecular weight of the purified protein was calculated to be about 11 000 on SDS-PAGE. The whole primary structure of the purified epididymis-specific protein was determined by N-terminal amino acid sequence analysis, digestion of lysyl-endo-peptidase and BrCN. The primary structure of PE4 showed a significant similarity to those of epididymis-specific protein-4(HE4). The level of amino acid homology was 78.49%. Then, it indicates that epididymis-specific protein belonged to disulfide-core-protein of antileukocyte proteinase inhibitor(ALP) and there is a important function in sperm maturation.

Photocatalytic Synthesis of MAA from Propylene and Carbon Dioxide over Cu/WO₃-TiO₂ Catalyst

MEI Chang-Song, ZHONG Shun-He

2005, 26(6):  1093-1097. 

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Photocatalytic synthesis of hydrocarbon oxygenates from CO₂ with hydrocarbons is of great importance to environmental protection, utilization of carbon resources and synthetic chemistry. Adsorption property of CO₂ and C₃H₆ and photo-stimulated surface reaction to synthesize methacrylic acid from CO₂ and C₃H₆ over the coupled semiconductor WO₃-TiO₂ catalyst with metallic Cu supported were studied. The experimental results reveal that the three kinds of active sites exist on the surface of Cu/WO₃-TiO₂ catalyst: Metallic site Cu, Lewis acid sites W⁶⁺ and Ti⁴⁺, Lewis base sites bridge O in W_OTi and terminal O in WO. Chemisorbed CO₂ on the surface of Cu/WO₃-TiO₂ catalyst forms high active horizontal state Cu_COO→Ti⁴⁺(or W⁶⁺) with the synergic action of metallic site Cu and Lewis acid sites Ti⁴⁺(or W⁶⁺), while dual-sites adsorption of β-H and β-C of C₃H₆ which forms state Cu_CH2C(CH₃)_H→OW, is found mainly on the Lewis base-site WO and the metallic site Cu, respectively. Blue-shifting of band edge of the absorption spectra and increasing of the photo absorption capacity on Cu/WO₃-TiO₂ catalyst improve the catalysis property of Cu/WO₃-TiO₂ catalysts. Photo-quantum efficiency of the reaction is the highest among the others, which reaches 19.7%. The selectivity of MAA is over 95% on 1%Cu/10%WO₃-TiO₂ catalyst under the proper reaction conditions(SV=200 h^-1, p=0.1 MPa, T=383 K and P=125 W). Based on the experimental results above, a possible mechanism is proposed for the photo-stimulated surface reaction to synthesize methacrylic acid from CO₂ and C₃H₆ over Cu/WO₃-TiO₂ catalysts.

Photoelectrochemical Performance of Nanostructured TiO₂/CTCMT Composite Film Electrode

HAO Yan-Zhong, WU Wen-Jun

2005, 26(6):  1098-1101. 

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The photon-current conversion properties of nanostructured TiO₂/CTCMT composite film electrode were studied by using the photocurrent action spectra and the photocurrent dependence of potential. The bandgap of CTCMT film is 2.36 eV. The diagram of energy level of CTCMT film was determined with cyclic voltamogram and photoelectrochemical method. The valence band of CTCMT film is -5.52 eV, the conduction band is -3.16 eV, the p-n heterojuction exists in the nanostructured TiO₂/CTCMT film electrode, which favors the separation of electron/hole pairs generated by photoexcitation. The nanostructured TiO₂/CTCMT film electrode can enlarge the visible optical absorption region and obviously increase the photocurrent. The photocurrent threshold shifts to more than 600 nm, thus the photoelectric conversion efficiency is improved.

Effect of Temperature on DSC Modules Performance with Different Solvents in Electrolyte

DAI Song-Yuan, CHEN Shuang-Hong, XIAO Shang-Feng, SHI Cheng-Wu, HUANG Yang, KONG Fan-Tai, HU Lin-Hua, PAN Xu, WENG Jian, GUO Li, WANG Kong-Jia

2005, 26(6):  1102-1105. 

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Dye-sensitized solar cells(DSCs), as a new innovative technology, are on-going to commercial and industrial production since the pioneer work by Prof. M. Grtzel in EPFL. We here investigated the temperature dependence of DSC modulus performance with different solvents in the electrolyte. The DSC modulus was assembled according to the way of future industrial production, with the size of 15 cm×20 cm, and the active area is ratio 65%. Temperature range from -40 to 60 ℃ was tested in this paper. The different solvents in the electrolyte, including acetonitrile(ACN), valeronitrile(VN), 3-methoxypropionitrile(MPN) and its mixture solution in the electrolyte, were also investigated in this paper.

Preparation of CdTe/SiO₂ Nanocomplex via Electrostatic Interaction

ZHAO Kui, LI Jun, WANG Lin, PAN Kai, LIU Yan-Mei, BAI Yu-Bai, LI Tie-Jin

2005, 26(6):  1106-1109. 

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Monodispersed 80 nm silica spheres were prepared in alcohol solvent by using tetraethyl-orthosilicate as the precursor, and functionalized with 3-aminopropyltriethoxysilane. The CdTe nanocrystals were synthesized in aqueous solution by using thioglycolic acid as the stabilizing agent. Additionally, CdTe nanocrystals were adsorbed on the surface of silica sphere in aqueous solution through electrostatic function. It was found that the CdTe nanocrystals photoluminescent spectra had an obviously shift to long wavelength.

Performance of Intermediary Temperature Solid Oxide Fuel Cell with Methanol as Fuel

BI Zhong-He, CHENG Mo-Jie, WU He-Jin, DONG Yong-Lai, YI Bao-Lian

2005, 26(6):  1110-1113. 

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Anode-supported solid oxide fuel cell with LDC-LSGM bilayer electrolytes and GDC+NiO anode substrate was fabricated and operated by using H₂ and methanol as the fuels respectively at temperatures from 650 to 800 ℃. At 800 ℃, the single cell exhibits the maximum output power density of 1.54 W/cm² with H₂ as the fuel and that of 1.07 W/cm² with methanol as the fuel. The impedance spectra of the single cell show some differences when the two different fuels are respectively used, and the anode activity towards methanol is the key factor for the cell performance.

Promotion Effect of Molybdophorsphoric Acid on Oxygen Reduction for Cathode of DMFC

SU Yi, LIU Chang-Peng, SHAN Yi-Bin, LI Xu-Guang, XUE Xin-Zhong, XU Wei-Lin, TIAN Tian, ZHOU Xiao-Chun, XING Wei, LU Tian-Hong

2005, 26(6):  1114-1117. 

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One kind of heteropolyacids(H₄PMo₁₂O₄₀·xH₂O)is introduced into the cathodic electro-catalyst of direct methanol fuel cell(DMFC) as an additive. The electrochemical result shows that these modified electrodes display an excellent eletrocatalytic activity for oxygen reduction reaction. Using the catalyst modified by PMo₁₂ the catalysis activity for the oxygen reduction reaction can be improved by a factor of 56.3% compared with Pt/C catalyst with the same platinum loading. This effect is also elucidated in the performance of single cell for DMFC. The peak value of power density is 28% higher than DMFC with a conventional electrode. These are may be due to the specific Keggin structure of the PMo₁₂. A better stability is obtained when the PMo₁₂ is introduced into the electrode.

DFT Study of Inserted Cluster Modeling of Rutile TiO₂(110) Surface

TAN Kai, LIN Meng-Hai, WANG Nan-Qin, ZHANG Qian-Er

2005, 26(6):  1118-1121. 

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According to metal oxide cluster modeling principle, we have calculated TiO₂(110) surfaces by means of density functional theory. The calculation results demonstrate that the theoretical description of solid character and electronic state explains the electronic behaviour of metal adsorbed on TiO₂ surface. The surface energy gap and the electronic structures were compared with the experimental data. Our studies of model also demonstrate the efficiency of the other metal oxide surface.

CO₂-Dehydrogenation of Ethane over Co-MCM-41 Catalyst

LI Ya-Nan, GUO Xiao-Hong, ZHOU Guang-Dong, BI Ying-Li, LI Wen-Xing, CHENG Tie-Xin, WU Tong-Hao, ZHEN Kai-Ji

2005, 26(6):  1122-1125. 

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MCM-41 mesoporous molecular sieves containing different contents of cobalt was synthesized by direct insertion of cobalt ions as the precursor prepared at room temperature in an initial stage of the synthesis. The catalysts were characterized by XRD, IR and TG-DTA techniques. The catalytic properties of this series of catalysts for the title reaction were tested with a continuous-flow fixed-bed quartz reactor. The experimental results indicate that a 39.54% conversion of ethane and a 98.59% selectivity of ethylene were achieved over 3%Co-MCM-41 catalyst in the CO₂-dehydrogenation of ethane. The content of cobalt and reaction temperature are important influence factors for the reaction. The 3%Co-MCM-41 showed a high activity for dehydrogenation of ethane to ethylene, and CO₂ could eliminate the deposited carbon on the catalysts, which favored the title reaction.

An Ab Initio Study on Stability of Three Isomers of C₂₀

ZHANG Guo, ZHANG Ming-Yu, SUN Chia-Chong

2005, 26(6):  1126-1129. 

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Three isomers of C₂₀, bowl, cage, and ring, were investigated by using the HF, B3LYP, MP2, QCISD methods at 6-31G and 6-31G^* level to obtain the optimized geometries and the order of their stability was as follows: Ring >Bowl >Cage. The calculated results show that the molecular orbital has multi-center characters and the electronic delocalization is favourable for bonding between atoms and can avoid the strong tension. This is the reason that the isomer of cage can exit stably though it breaks "isolated pentagon rule".

iso-Butane/1-Butene Alkylation Reaction and Deactivation of Superacid(SO₄^2-/ZrO₂) Catalysts

ZHANG Qiang, JIAO Qing-Ze, MIN En-Ze

2005, 26(6):  1130-1132. 

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The acidity and reactivity of superacid(SO^2-₄/ZrO₂) catalysts in the iso-butane/1-butene alkylation were investigated. It was found that the acidity of the solid superacid is related to the baking temperature, and higher baking temperature is advantageous to increasing the acidic strength of the catalysts, but too high baking temperature resulted in the decrease of the acidic strength and amount. It was also found that the reactivity of superacid(SO^2-₄/ZrO₂) catalysts in the iso-butane/1-butene alkylation corresponds to the acidity, the stronger the acidity is, the higher the reactivity is. But the stronger acidity resulted in the fast decrease of activity, which was attributed to the fast carbon deposit on the catalyst surface.

A Theoretical Study on Potential Energy Surface of Reaction Between Ketenyl Radical(HCCO^·) and Nitrogen Dioxide(NO₂)

YU Jian-Kang, WEI Zhi-Gang, HUANG Xu-Ri, LI Zhou, LI Qian-Shu, SUN Chia-Chong

2005, 26(6):  1133-1136. 

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The singlet potential energy surface for the reaction of HCCO radical with molecule NO₂ is worked out at the CCSD(T)/6-311G(d,p)//MP2/ 6-311G(d,p)+ZPE level of the theory. The possible reaction mechanism includes three reaction steps: (1) the O atom of the molecule NO₂ attacks the C atom of the radical HCCO to form the adduct isomers 1 or 2; (2) the isomers 1 and 2 decompose into the products NO and OC(H)CO via the N_O bond break; (3) the product OC(H)CO changes to the products HCO and CO via the C_C bond break. Thus, the reaction HCCO+NO₂ may produce the products NO, HCO and CO.

Microwave-irradiation Promoted Cu/ZnO/Al₂O₃ Catalyst for Hydrogen Production from Steam Reforming of Methanol

ZHANG Xin-Rong, YAO Cheng-Zhang, WANG Lu-Cun, CAO Yong, WU Dong, SUN Yu-Han, DAI Wei-Lin, FAN Kang-Nian

2005, 26(6):  1137-1139. 

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We demonstrate for the first time that a short time of microwave irradiation on the oxide precursor of a Cu/ZnO/Al₂O₃ catalyst can provide unique opportunity for tailoring the microstructure and activity of the catalyst for methanol steam reforming. It is shown by in situ XRD that a considerable increase in the microstrain of Cu nanocrystals could be achieved in the catalysts processed by microwave irradiation for 3₁0 min, which correlates well with the enhanced CH₃OH conversion as observed on the corresponding samples. The present work also confirms that although the high specific surface area of Cu is a prerequisite for catalytic activity, it does not account for the observed changes in activity and selectivity alone without taking bulk microstructural changes into account.

Synthesis of MCM-22 with High SiO₂/Al₂O₃ Ratio and Its Catalytic Performance on C₄-olefins Cracking Reaction

ZHAO Guo-Liang, TENG Jia-Wei, XU Ning, TANG Yi, XIE Zai-Ku, YANG Wei-Min, CHEN Qing-Ling

2005, 26(6):  1140-1142. 

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MCM-22 zeolite with a high SiO₂/Al₂O₃ ratio was synthesized in the hydrothermal system of Na₂O-SiO₂-Al₂O₃-(CH₂)₆NH and its catalytic performance in the C₄-olefins cracking reaction was investigated. It was found that MCM-22 showed an excellent catalytic performance on C₄-olefins cracking reaction to produce propylene. The results indicated that high temperature and high LHSV(liquid hourly space velocity) were favorable for the production of propylene with a high selectivity. Lifetime test of HMCM-22 and HZSM-5 for the cracking of C₄ olefins indicates that the deactivation rate of HMCM-22 is lower than that of HZSM-5.

Theoretical Studies on Transport Behavior and Model of Ag/TCNQ Double-layer Thin Film

XIE Heng-Bo, JIANG Yi-Ming, GUO Feng, LIU Ping, Li Jin

2005, 26(6):  1143-1145. 

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Ag/TCNQ double-layer films with different thicknesses were prepared on glasses substrate by alternately vacuum deposition of Ag and TCNQ. The metal-organic complex Ag-TCNQ formed through transport at room temperature and in atmosphere environment. The transport behavior in the film was studied by using transmission spectrum to monitor the process. An abnormal accelerated transport phenomenon was observed with the decrease of the thickness of the film, which was different from the parabola law between transport distance and transport time when the film was thicker. Tunneling and non-tunneling models were established respectively based on whether the tunneling condition was met. The theoretical analyses were carried out in detail.

Measurement of Diffusion Coefficient of Fe³⁺ in Ionic Liquid BPBF₄ by Chronoampermetry

YANG Jia-Zhen, JIN Yi, PAN Wei, ZANG Shu-Liang

2005, 26(6):  1146-1148. 

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The chronoampermetry was used to measure the Fe³⁺ diffusion coefficient of 0.031 16 mol/kg of FeCl₃ in the ionic liquid, BPBF₄, at GC working electrode referred to Al/Al³⁺ and at different scan rates over the temperature range from 293.15 to 343.15 K. Since the Fe³⁺ reduction reaction is a reversible process with one transfer electron, according to Cottrell's equation, the values of diffusion coefficient of Fe³⁺ at different temperatures were estimated. As temperature increases, the values of the diffusion coefficient also increase owing to the diminution of the BPBF₄ viscosity. The values of diffusion coefficient were fitted with the method of least-square according to Arrenius' equation, and value of diffusion activation energy of Fe³⁺, E_D=49.5 kJ/mol, was obtained from Arrenius' slope.

Miscibility-complexation Behavior and Surface Characterization of Modified Phenoxy Resin/Poly(butyl methacrylate-co-4-vinyl pyridine) Blends

LIU Shi-Yong, CAI Qian, ZHU Hui, JIANG Ming

2005, 26(6):  1149-1155. 

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A series of poly(butyl methacrylate-co-4-vinyl pyridine) copolymers with varying 4-vinyl pyridine(VPy) contents were synthesized. Phenoxy resin was modified to different extents by acetylation. Viscometry and laser light scatering(LLS) were then used to study the dependence of complexation behavior on the densities of specific interaction groups, while DSC was used to investigate the bulk miscibility of the polymer blends. Combined with viscometry, LLS and DSC data, an complete immiscibility-miscibility-complexation phase map was obtained. Finally, XPS was used to investigate the surface composition of the polymer blends or complexes with different strengths of specific interactions and probe the effect of bulk miscibility states on the surface properties. It was found that interpolymer complexation can greatly eliminate the surface enrichment in polymer blends with different surface free energy.

Surface Modification of Poly(ether urethane) Membrane with RGD and Its Cytocompatibility of Human Endothelial Cell

YU Guan-Hua, JI Jian, WANG Dong-An, SHEN Jia-Cong

2005, 26(6):  1156-1161. 

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XPEO-MDI-PEOX"-type pentablock coupling copolymers were specially designed as the surface additives for poly(ether urethane)(PEU). When the pentablock coupling polymers were blended with PEU, ATR-FTIR indicates that the middle blocks(diphenylmethane diisocyanate(MDI) of the pentablock copolymers could incorporate with the hard blocks of PEU chains through hydrogen binding, which improved the stability of the "XPEO-MDI-PEOX". Based on the special hydrogen binding stabilization and self-migration of "XPEO-MDI-PEOX", RGD presenting surfaces were developed via two different methods. The first approach involved directly blending of RGD-tethered poly(ethylene oxide)-MDI-poly(ethylene oxide)-RGD in PEU. In the second approach, the mesyl-PEO-MDI-PEO mesyl were non-covalently introduced onto the PEU surfaces by dip coating, upon which the RGD was covalently immobilized in situ by cleavage of the original mesyl end groups. The human endothelial cell tests indicate that the RGD presenting films modified by both method could promote endothelial cells attachment and growth significantly. And the cytocompatibility of PEU modified by the first method was better than that by the second method. The two simple methods of surface treatment may have a potential for tissue engineering and other biomedical applications.

Surface Biomimetic Waterproof Modification of Chitosan Rod

HU Qiao-Ling, LEI Yong, ZHANG Zhong-Ming, SHEN Jia-Cong

2005, 26(6):  1162-1165. 

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In-situ precipitation method was developed to prepare chitosan rod. But high water penetrating rate and large amount of water absorption of chitosan rod limit its practical application as internal fixation of bone fracture. Many terrestrial plants and animals are water-repellent. It was believed that water-repellency is based on the surface roughness caused by different microstructures, together with the waterproof properties of the epicuticular wax. The surface acetylation and bio-ester coating were adopted as the method of surface waterproof modification of chitosan rod. Firstly, a scraggy surface was obtained though the surface acetylation of chitosan rod. Subsequently bio-ester was coated onto the modified surface. Then the final waterproof effect was characterized by contact angle and water absorption rate also. Soaked in the simulated body fluid(SBF) for three months, little mechanical properties attenuation shows that the surface composite modification is a method with a feasibility to improve the waterproof property of the chitosan rod.

Monitoring Adsorption in situ and Kinetic Studies of Low-density Lipoprotein onto Cholesterol Modified Dextran Using Quartz Crystal Microbalance

HAN Song-Yan, LIU Dong-Bo, HUANG Liang, WANG Shen-Qi, LIU Qing-Ping, Anzai Jun-ichi, Tetsuo Osa, CHEN Qiang

2005, 26(6):  1166-1169. 

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The use of quartz crystal microbalance(QCM) for monitoring in situ the adsorption of low-density lipoprotein(LDL) onto cholesterol modified dextran(CMD) was described. The kinetic studies were made. The experimental results show that kinetic curves are fitted for that of Langmuir adsorption equation quite well, when LDL mass concentration(ng/μL) are 9.9, 12.38, 14.14, respectively, and the rate constants for adsorption(mol·L^-1·s^-1) and adsorption capacity(ng/cm²) are estimated to be (0.047 7), 0.053 6, 0.062 8 and 107.6, 139.6, 167.9, respectively. The maximal LDL adsorption capacity attains 284.8 ng/cm² and the adsorptive efficiency was calculated as 72.91%.

Piezoresistance Behavior of Polyvinyl Chloride/Carbon Black Conductive Composites

XU Wen-Wu, SONG Yi-Hu, ZHOU Jian-Feng, ZHENG Qiang, ZHANG Ming-Qiu

2005, 26(6):  1170-1173. 

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The piezoresistive behavior of polyvinyl chloride/carbon black(PVC/CB) conductive composites subjected to uniaxial compression-decompression cycles was studied. The composites exhibited a significant piezoresistance, when CB mass fraction w was located in the vicinity of the percolation threshold wc. The composites displayed a positive pressure coefficient(PPC) effect at w<wc and negative pressure coefficient(NPC) effect at w>wc. Uniaxial compression might facilitate the NPC effect or weaken the PPC effect when w was located in the vicinity of wc.

Preparation and Properties of Biodegradable Microspheres Containing 5-Fluorouracil

YIN Jing-Bo, CHEN Hong-Dan, LUO Kun, ZHUANG Xiu-Li, CHEN Xue-Si, CAO Tian

2005, 26(6):  1174-1176. 

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Microspheres containing an antimetabolite drug 5-Fluorouracil were prepared from (poly(lactic) acide)(PLA) or poly(lactic acid)-polyethylene glycol(PLA-PEG) as the carrier by using a water-in-oil-in-water emulsion solvent evaporation technique. The conditions of the microspheres preparation such as polymer concentration in organic solvent, relative molecular weight of PLA-PEG and PLA/PEG mass ratio were discussed. The surface morphology and the size of the microspheres were observed by SEM. The drug content of microspheres was examined by TGA and the drug release in vitro was evaluated. According to the results, the drug content increased with the nano-silica used. The highest drug content in this study was 39.9%. The drug-release kinetics satisfied the requirements of controlled drug-release.

Effect of Heat-treatment Atmosphere on the Near-infrared Absorption of the Fluorinated Poly(aryl ether)

LI Ai-Ze, JIN Yu-Hui, LIU Bai-Jun, JIANG Zhen-Hua

2005, 26(6):  1177-1179. 

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C-1s and O-1s of the 3,5-bitrifluoromethylated poly(aryl ether) terminated with phenylethynyl moieties(2CF₃-PAE-PEP) before/after crosslinking were tested by the X-ray photoeletron spectroscopy(XPS). The measurements show that some of the C_O bonds in the molecule structure will be broken if the films are crosslinked in the air, which is able to form some new CO bonds with the oxygen in the air. However, the ratios of the groups in the films cured in nitrogen remain the same as that of the uncured samples. It is the the forth harmonic of the stretching vibration of CO bond(4ν^<sup>φ_<sub>C=O) that causes the absorption loss at the wavelength 1 382 nm.

Synthesis and Properties of Electron Beam Irradiated Soluble Poly(aryl ether ketone)s Containing Thioether Group

ZHOU Hong-Wei, GAO Zi-Hong, LIU Xin-Cai, CHEN Chun-Hai, ZHANG WanJin

2005, 26(6):  1180-1182. 

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Soluble poly(aryl ether ketone)s containing thioether moieties that provide crosslinking function group were synthesized. These polymers exhibit an excellent solubility in general organic solvent. The properties before and after irradiation were investigated by differential scanning calorimetry(DSC), thermogravimetric analyses(TGA) and gel permeation chromatography(GPC). The GPC results indicate that the irradiated polymer exhibited an increasing molecular weight with increasing the irradiation dose. The DSC and TGA results also demonstrate that the glass transition temperature and thermal stability of the irradiated polymer were higher than those of un-irradiated polymer. The tensile strength and modulus of irradiated polymer increased, while the elongation at break decreased with increasing the irradiation dose.

Fabrication of Microporous Thin Films from Polyelectrolyte Multilayer Films

QIN Sheng, CHEN Liu-Sheng, SHI Yi, LIAO Qi, JIN Xi-Gao

2005, 26(6):  1183-1185. 

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The polyelectrolyte multilayer films were prepared by the layer-by-layer deposition of polyelectrolytes on the charged surfaces substrates. A simple process was developed to create a large area and discrete microporous thin films based on PDDA/NaPSS multilayer films by using immersing the multilayer film into pure water at an appropriate temperature and period. The microporous morphology of the multilayer film is controlled by temperature and time, and observed by atomic force microscopy. It is observed that the total area of the micropores in the films increased with immersing temperature and time. In addition, the microporous process of PEM films in hot pure water is discussed. This unique way to fabricate the microporous films has potential applications to the fields from microelectronic materials to biomaterials.

Preparations of Conductive Polypyrrole/Polystyrene Composite Microspheres with Controlled Shell Thickness and Polypyrrole Hollow Capsules

HUANG Li-Yan, DU Jiang, LIU Zheng-Ping

2005, 26(6):  1186-1188. 

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Monodisperse polypyrrole(PPy) composite microspheres and hollow capsules based on the monodisperse core-shell gel template particles were prepared. The core-shell gel particles were obtained by the inward sulfonation of monodisperse polystyrene particles. The shell thickness and core size were synchronously controlled in the particle radius range. After the polymerization initiated by ammonium per sulfate(APS), PPy was formed in the sulfonated polystyrene shell. PPy hollow capsules were derived after the polystyrene cores were dissolved: their cavity size and shell thickness were synchronously controlled by using core-shell gel particles with different sulfonation extent. It is interesting that if Fe³⁺ was adsorbed into the sulfonated polystyrene shell as the initiator, the PPy-shell collapsed into a pile of small particles when the polystyrene core was dissolved.