Table of Content

10 February 2005, Volume 26 Issue 2

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Articles

Synthesis of ZnS Hollow Submicrometer Spheres in an Aqueous Ternary-additive System

CAO Jie-Ming, DENG Shao-Gao, FENG Jie, GUO Jing, ZHANG Fang, TAO Jie

2005, 26(2):  199-203. 

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In this paper, it is demonstrated that the utility of poly-(ethylene glycol)(PEG), methacrylic acid(MAA) and sodium dodecylsulfate(SDS) can exert an exceptional control on the crystallization of ZnS by the in-situ polymerization of MAA monomers through addition of a certain amount of initiator, hereby provide a facile synthesis route to hollow ZnS spheres. The products obtained were characterized by using X-ray diffraction(XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM), and UV-Vis optical absorption. TEM studies suggest that the hollow spheres with diameters ranging from 300 to 400 nm are obtained. The wall thickness was estimated to be about 50 nm. SEM images show that the wall is constituted of compact worm-like structures, which consist of well-aligned primary nanoparticles. It was also found that the variation of surfactant concentration drastically changed the morphology of the produced ZnS products due to the corresponding transformation of micelles' structure. At a relative higher SDS concentration, ZnS spherical assemblies of platelike crystallites were obtained. The formation of the hollow spherical structure was interpreted in terms of the core-shell mechanism.

Synthesis and Photochroism of a Novel Organic-inorganic Nanocomposite Film Entrapping Tungstosilicate Acid

HUANG Yan, PAN Qing-Yi, CHENG Zhi-Xuan, ZHANG Wen, XIA Wei

2005, 26(2):  204-208. 

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A novel photochromic organic-inorganic nanocomposite film was prepared through entrapping Keggin structure H₄SiW₁₂O₄₀ into MAAM/VTEOS/TEOS matrix by combining supramolecular self-assembly technology with sol-gel process. The composite film was characterized by IR, XRD and TG-DSC, and its photochromic behavior and mechanism were also studied and discussed. The transparent film changed from colorless to dark-blue under UV irradiation and was measured by UV-Vis and ESR spectra. The results indicate that [SiW₁₂O₄₀]^4- anions maintain Keggin structure in the composite film and interacted strongly with _NH₂ group of the matrix via hydrogen bond. After irradiation under UV light, a hydrogen atom is transferred to a [SiW₁₂O₄₀]^4- anion, and a free radical is formed at the same time. The bleaching process is closely related to the presence of O₂, and the experiments show that the composite film has excellent photochromic properties, with a short response and bleaching time and good reversibility.

Components Analysis and Antibacterial Activity of Calamine

GUO Yi-Ming, ZHAO Jing-Zhe, YU Kai-Feng, LIU Yan-Hua, WANG Zi-Chen, ZHANG Heng-Bin

2005, 26(2):  209-212. 

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The components of traditional Chinese medicine calamine were determined with thermogravimetric analysis method and otherwise. Nanosized zinc carbonate alkali and nanosized zinc oxide were synthesized, and nanosized calamine was prepared. The particle size and morphology of calamine, zinc carbonate alkali and zinc oxide were determined by laser size analysis device and transmission electron microscope(TEM). The antibacterial activity of calamine and its components were determined by using beaker disc method. The result shows that the antibacterial activity of calamine was decided by the content and particle size of zinc oxide, and the antibacterial activity of nanosized calamine was better than that of calamine. Nanosized calamine possesses the characters of calamine and nanosized traditional Chinese medicine, and it has the double activities of calamine and nanoparticles. Zinc carbonate alkali and nanosized zinc carbonate alkali have not antibacterial activity for the four bacteria in this paper.

Oxidation Behavior of Zinc Vapor and Crystalline Morphologies of ZnO

CHEN Yi-Feng, Peng Chang-Hong, TANG Mo-Tang

2005, 26(2):  213-217. 

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The kinetics of oxidizing zinc vapor in different atmospheres at an elevated temperature was determined by thermogravimetric analysis and the morphologies of products were examined by scanning electron microscopy. The results showed that the product morphologies were of amorphous, granular, needle-like ZnO when the kinetics progressed linearly and the morphologies of tetrapod and/or multipod-like ZnO appeared as the kinetics proceeded parabolically. The cause of the kinetics change was the coexistence of atomized zinc and tiny zinc droplets formed in zinc vapor under proper conditions. The kinetics advanced linearly as the atomized zinc was oxidized while the kinetics followed the interface reaction R₃ and Ginstling-Brounstein D₄ model with apparent activation energy of 10⁶.3₁08.2 kJ/mol and 114.2-117.3 kJ/mol respectively in the early and later stages of the zinc droplets oxidation. The oxidation process of the tiny zinc droplets is controlled by the outward diffusion of Zn through the oxidation scale and the diffusion coefficient D=2.46×10^-5-9.70×10^-5 cm²/s.

A Study of In-line Dialysis Combined with Capillary Electrophoresis——Realization and Preliminary Applications of Capillary Electrophoresis with Dialytic Sampling Function

YU Yan-Lin, CHEN Hua, XIAO Shang-You, LI Hong-Yi, TAO Ran, XIA Zhi-Ning

2005, 26(2):  218-221. 

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A novel method of in-line coupling of dialysis with capillary electrophoresis, which eliminates the influence of macromolecules and particles in sample matrixes during the analysis of small molecules, was established in this paper. A polysulfone membrane, which was prepared in the inlet end of the separation capillary by phase-inversion process, cut off macromolecules efficiently and durably, so the capillary can be used for clean-up sampling. Using this capillary in electrophoresis, little column efficiency lost was achieved and the RSD of migration times and peak areas of chlorpheniramine were 0.8% and 4.6%, respectively. During the continuous using of this capillary for 12 h, the performance of the membrane changed little. This technology was applied in the analysis of free caffeine in coffee milk, and with little interference, the concentration was determined to be 0.68 mmol/L. When this method was applied in interaction analysis, the binding constant of promethazine hydrochloride with bovine serum albumin was obtained, that is 1.47×10⁴ L/mol.

Piezoelectric and Electrochemical Characteristics of Oriented Antibody Immobilization Mediated by Gold Nanoparticle-labeled Protein A

DING Yan-Jun, WANG Hua, LI Ji-Shan, SHENGuo-Li, YU Ru-Qin

2005, 26(2):  222-226. 

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Mediated by gold nanoparticle-labeled protein A(Nanogold-PA), the oriented immobilization of antibodies on the surface of the quartz crystal microbalance(QCM) was carried out by using C_ 1q antibody as a model test system. The immunoreaction process and piezo-response features of the created immunological interface were real-time monitored by using the QCM. It is found that the developed Nanogold-PA immobilization procedure has some advantages over the traditional direct protein A binding procedure, including activation-free for sensing interface, high immunoactivity of bound antibodies and high sensitivity for the corresponding antigens. Moreover, the kinetic characterizations of cyclic voltammograms and electrochemical impedance spectroscopy were performed. The experimental results indicate that the proposed Nanogold-PA immobilization procedure may be popularized as a general alternative method of designing various immunosensing platforms.

Determination of Nitrophenols of Environment by Dual-electrode and Dual-channel Electrochemical Detection of Capillary Electrophoresis with Polyvinylpyrrolidone Modified Carbon Paste Electrode

YANG Bing-Yi, MO Jin-Yuan, LAI Rong

2005, 26(2):  227-230. 

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A new method for determination of nitrophenols was presented based on polyvinylpyrrolidone modified carbon paste electrode coupled to a dual-electrode and dual-channel electrochemical detection system of capillary electrophoresis. In this system, two working electrodes and two amperometric detector were employed. The oxidative and reductive detection potentials were set at +0.5 V and -1.4 V vs. SCE, respectively. The ratio of reductive and oxidative current response(N_c=i_r/i_o) obtained at each electrode was also used to verify sample purity. Four nitrophenols were determined with oxidation and reduction at the same time. Efficient, rapid and versatile electrophoretic conditions were obtained with 25 mmol/L Tris-2.85 mmol/L citric acid-10 mmol/L β-CD-10% ethanol. The effects of the working electrode, detection potential, buffer, the concentration of β-CD and ethanol on the separation were investigated. The output signal was processed by spline wavelet least square, which can extract useful information from high noise signals. The method was applied to separation and determination of sample of environment with satisfactory results.

Electrochemical Detection of DNA Sequences Using Nano-magnetic Particles

LIU Ai-Li, PENG Tu-Zhi, CHENG Qiong

2005, 26(2):  231-234. 

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The carboxyl nanoparticles were prepared by dispersing polymerization method. The oligonucleotides were immobilized on the surface of the nano-magnetic particles by EDC and NHS. The novel DNA probe of magnetic particle can concentrate the trace amount of complementary DNA selectively from the sample solution onto the gold film electrode under a magnetic field. Differential pulse voltammetry was used to detect DNA with an electroactive indicator of neutral red which could bind to double stranded DNA. The linear range for the determination of target DNA is from 1.0×10^-6 to 5.0×10^-9 mol/L, and the detection limit is found to be 8.6×10^-10 mol/L.

Identification and Quantification Analysis of Active Ingredient and Main Impurities in Monosulfuron

FAN Zhi-Jin, QIAN Chuan-Fan, AI Ying-Wei, CHEN Jun-Peng, LI Zheng-Ming

2005, 26(2):  235-237. 

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Monosulfuron was identified by m.p., IR, NMR, MS, UV and HPLC/MS analysis in this study, the results indicate that, the active ingredient of monosulfuron was N-[2'-(4'-methyl) pyrimidyl]-2-nitrobenzensulfonylurea, it's main impurities were 2-amino-4-methylpryrimidine, 2-nitrobenzensulfonamide and ethyl 2-nitrobenzensulfonyl carbamate. The method of reverse HPLC analysis for active ingredient and main impurities in monosulfuron were established by using 250 mm× 4.6 mm stainless column of ODS 5 μm with V(CH₃OH)∶V(H₂O)= 60∶40 containing H₃PO₄ ( pH 3.0) as a mobile phase, 0.8 mL/min of flow rate, 225 nm as UV determination wave length. All components of monosulfuron which consisted of more than 0.1% were quantitated.

A Solid-state Ion-selective Electrode for Mercury with Tweezer-type Calix[4]arene Derivative as the Probe on PVC Film

Lv Jian-Quan, ZENG Xian-Shun, AI Juan, PANG Dai-Wen

2005, 26(2):  238-240. 

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A new solid-state mercury ion-selective electrode was prepared by directly coating the surface of a glassy carbon electrode with tetrahydrofuran solution containing PVC, 25,27-dihydroxy-26,28-bis[(1'-naphthalene) selenopropoxy] calix[4]arene, dioctyl phthalate and potassium tetrakis(4-chlorophenyl) borate. The response of the electrode is linear with a good Nernstian slope of 31.5 mV/decade over an Hg²⁺ ion concentration range of 5.0×10^-9—5.0×10^-2 mol/L and a detection limit of 1.0×10^-9 mol/L. The response time to achieve a 95% steady potential for Hg²⁺ detection is less than 30 s, and the electrode is suitable for use within the pH range of 2—4. The selectivity for Hg²⁺ relative to several alkali, alkaline earth, transition and heavy met al ions is good. The mechanism of the potential response of this system was also discussed.

Preparation and Performance of a De-tert-butyl-calix[8]arene-bonded Stationary Phase for HPLC

LI Lai-Sheng, DA Shi-Lu, FENG Yu-Qi, LIU Min

2005, 26(2):  241-243. 

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A calix[8]arene-bonded gel silica stationary phase(DCABS) was prepared by using coupling reagent(KH560). Its structure was characterized by FTIR, elemental analysis and thermal analysis. The chromatographic performance of DCABS was studied by using different solutes as probes and stationary phases as reference. The results show that the new material has an excellent reversed-phase chromatographic property. The new bonded phase can provide various sites for analytes, such as the hydrophobic interaction, hydrogen-bonding, π-π, electrostatic interactions. Meanwhile, it was observed that the chromatographic performance of DCABS is partially different from CABS because of elimination of the butyl groups.

Adsorption Mode of Di-dentate Ligand Modified Zirconia Stationary Phase Surface

YAO Li-Feng, FENG Yu-Qi, DA Shi-Lu

2005, 26(2):  244-246. 

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Various zirconia stationary phases were prepared by modification with di-dentate Lewis bases: dodecyl-N,N-diacetic acid(RNCC), dodecyl-N-acetic acid-N-methyleneposphonic acid(RNCP), dodecyl-N,N-dimethylenephosphonic acid(RNPP) and dodecencylsuccinic acid(RCC). The color reaction of RNPP-ZrO₂ and RNCP-ZrO₂ with ammonium molybdate indicate there are free phosphonic groups on the surface of the stationary phases, and the FTIR spectra of RNCC-ZrO₂ and RNCC-ZrO₂ indicate there are free carboxyl groups. The RCC-ZrO₂ is far more stable than RNCC-ZrO₂ under alkali station. The results of color reaction, FTIR spectra and the stability test of stationary phases suggest that, due to the chelating effect, RNCC, RNCP and RNPP adsorb on zirconia with only one carboxyl or phosphonic group, however, RCC adsorb on zirconia with two carboxyl groups.

On-chip Labeling with NDA for Determining Glutathione in Single Cell Using Microfluidic Chip Electrophoresis

LING Yun-Yang, YIN Xue-Feng, FANG Zhao-Lun

2005, 26(2):  247-249. 

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A simple method for the detection of glutathione(GSH) in single human erythrocyte was developed using on-chip mode dynamic labeling by adding the 2,3-naphthalene-dicarboxaldehyde(NDA) simply in microchip electrophoresis buffer, with functional integration of cell sampling, single cell loading docking, lysing, dynamic labeling, electrophoresis separation and laser induced fluorescence(LIF) detection. By using a combination of hydrostatic pressure and low electric field, single cell sampling speed and long-term stability were improved. After lysing, the reaction between the released GSH and NDA included in electrophoresis buffer can be completed within a migrating distance of 0.5 cm in the microchip separation channel during electrophoresis. The average separation efficiency for GSH was 2.4×10⁶ plates/m, which was not a significant difference from off-chip derivatization. The GSH migration time on the on-chip mode and off-chip method were 116 and 110 s, respectively. The present method can be used to minimize the dilution of the contents of single cell during the derivatization to maintain favorable kinetics for the labeling reaction, simplify the cell treatment and save the sample and reagent. A half life of 5 days of GSH in human erythrocyte was found by using this method.

Synthesis of 3-Amino-6/8-Substituted-1H-pyrazolo[4,3-c]quinolines

QIAO Ren-Zhong, ZHANG Zi-Yi, ZHAO Yu-Fen

2005, 26(2):  250-253. 

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A simple synthesis of 3-amino-6/8-substituted-1H-pyrazolo[4,3-c]quinolines via closed ring reaction of 4-amino-3-aryl-5-mercapto-s-1,2,4-triazoles with 1,4-dihydro-4-oxo-quinoline-3-carboxylic acids in the presence of phosphoryl chloride, followed by the ring-opening reaction in the presence of hydrazine hydrate was described. This novel and straightforward method for the construction the 3-amino-1H-pyrazolo[4,3-c]quinolines can be carried out under mild conditions by using readily accessible or commercially available inexpensive materials. The new compounds were dertemined by elementary analyses, IR, ¹H NMR and MS spectra. Their spectral properities were also discussed. This mothod may represent a potentially useful route to otherwise laboriously accessible condensed pyrazoles ring systems. With the advantage of economy, a single pot procedure, excellent yields and mild conditions. This condensed pyrazoles can be synthesized on a large scale conveniently and economically.

Structure-activity Relationship Studies on 6-Naphthylmethyl Substituted HEPT Derivatives as Non-nucleoside Reverse Transcriptase Inhibitors Based on Molecular Docking

HE Yan-Ping, HU Hai-Rong, XU Liao-Sa, MENG Ge, FAN Kan-Nian, CHEN Fen-Er

2005, 26(2):  254-258. 

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The research on 1-[(2-hydroxyethoxy)methyl]6-(phenylthio)thymine(HEPT), as one of the most important reverse transcriptase(RT) inhibitors against human immunodeficiency virus(HIV), remains a hot issue these years. The complex models of a series of 6-napthylmethyl substituted HEPT analogues with HIV-1 RT have been obtained by employing molecular docking approach. Using the binding conformations of these HEPT analogues, self-consistent and highly predictive 3D-QSAR models have been developed by performing CoMFA and CoMSIA analysis, which further guide the design of new candidates in return. Mapping these models back to the topology of the active site of HIV-1 RT led to a better understanding of the vital inhibitor-HIV-1 RT interactions. Taking compound 13 and its β-isomer 24 as the representatives, the reasons for the activity difference of α-and β-series analogues were presented by employing ab initio molecular orbital theoretical method. The best resulting CoMFA and CoMSIA models had conventional r² values of 0.997 and 0.994, while their leave-one-out cross-validated q² values were 0.787 and 0.747, respectively, suggesting a good predictive ability of these two models. Our research results also suggested that CoMSIA model was somewhat equivalent to the COMFA one. These models offer insight into the structural requirements for the activity of HEPT analogues as promising inhibitors, since there is only speculative knowledge of the target.

Total Synthesis of Natural Product (±)-Aiphanol

WANG Xiao-Long, XIA Ya-Mu, FENG Jian-Peng, CAO Xiao-Ping, PAN Xin-Fu

2005, 26(2):  259-263. 

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A concise synthesis procedure for the total synthesis of natural product(±)-Aiphanol 12, a novel stilbenolignan having a stilbene-phenylpropane unit with a dioxane moiety, was achieved by using simple aldehydes as the starting materials. The key steps were oxidative coupling of coniferyl alcohol 4 with catechol 6 using Ag₂O as the catalyst to give the 1,4-benzodioxane intermediate 7, followed by a selective protection of the phenolic hydroxy group of 7 to afford 8, which was oxidized by NaIO₄/OsO₄(cat.) to give the key intermediate aldehyde 9. Then after Wittig-Horner reaction followed by conversion of Z-isomer to E-isomer using thiophenol in refluxing benzene in the presence of azoisobutyronitrile(AIBN) to produce 11, which underwent deprotection with diluted HCl in methanol to afford the titled compound(±)-Aiphanol 12 conveniently.

Preparation of Enantiomerically Pure 1-Methyl-7-oxabicyclo[2.2.1]heptan-2-one

GUAN Yu-Kun, FANG Li-Jing, ZHENG Guo-Jun, LI Yu-Lin

2005, 26(2):  264-266. 

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(±)-1-Methyl-7-oxabicyclo[2.2.1]heptan-2-one (1) is a versatile chiral building block for terpenoids. It could be applied in total synthesis of eudesmanes, agarofurans and norcarotenoids. Compound (±)-1 was reduced to alcohol (±)-2. Compound (±)-2 was esterified with commercial available optically pure (S)-(+)-mandelic acid. The diastereomeric ester mixture was separated with preparative HPLC method. After oxidation of the saponified products of diastereomeric ester (+)-4 and (+)-5 respectively, both optically pure enantiomers of compound 1 were prepared for the first time in four steps with an overall yield of 70%. The absolute configurations of (+)-1 and (-)-1 were determined as (+)-(1R,4S)-1-methyl-7-oxabicyclo[2.2.1] heptan-2-one and (-)-(1S,4R)-1-methyl-7-oxabicyclo[2.2.1] heptan-2-one.

Atom-economic Reaction: Diselenides Reacted with Terminal Alkynes to Synthesize Alkynyl Selenides Catalyzed by Cesium Hydroxy and Promoted by Air

XU Xin-Hua, LU Rui-Liang, ZHANG Qiu-Lin, CHEN Xiong, LI Yan-Jie, ZHANG Qing-Li

2005, 26(2):  267-269. 

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Under N₂ atmosphere and at room temperature, the reaction of diaryl diselenid(1.0 mmol) with terminal alkynes(2.2 mmol) catalyzed by cesium hydroxy gave exclusively (Z)-1,2-bis(arylseleno)-1-alkenes, but under air and at -10₀ ℃, the reaction gave alkyne selenides in 83%₉5% yields based on the selenium atoms. The method for the preparation of alkyne selenides has advantages of available starting materials and simple procedures. The reaction mechanism was proposed.

Synthesis and Crystal Structure of the Fused Quinazoline Spiro-heterocyclic Compounds

LI Xiao-Fang, FENG Ya-Qing, YOU Xu-Dong, HU Xiao-Fen

2005, 26(2):  270-272. 

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The new fused quinazoline spiro-heterocyclic compounds were synthesized by combining the fused thiazolidone and quinazoline structure with spiro-heterocyclic structure for the purpose to get novel bio-active compounds. Dipolar azomethine ylides reacted with dipolarphile 2-arylmethylene-9-benzylidene-5-phenyl-6,7,8,9-tetrahydro-5H-thiazolo[2,3-b]quinazoline-3-one via 1,3-dipolar cycloaddition to give nine fused quinazoline spiro-heterocyclic compounds. The configuration and conformation of the products were determined by elementary analysis, ¹H NMR, IR and X-ray crystal analysis. The results also revealed that the reaction was stereospecific.

Measurement of Diffusion Coefficients of Non-polar Alkane Solvents at Infinite Dilution in Polyethylene Membrane

JIANG Zhen, LI Ji-Ding, ZHAO Zhi-Ping, CHEN Cui-Xian YU Hong-Wei, ZHANG Zhi-Hua

2005, 26(2):  273-276. 

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Gas chromatography is a new, fast, accurate and convenient technique for studying the relationship between small molecule solvents and polymer membrane materials. Many parameters of dissolution and diffusing characters of a small molecule in a polymer can be measured by this method. The rentention time and the peak width at half-height of three small molecule solvents (n-heptane, n-nonane and n-decane) in the stationary phase of polyethylene were measured. The diffusion coefficients of the small molecule solvents at infinite dilution were calculated with van Deemter equations. The graphs plotted according to the results of the diffusion coefficients of the three solvents at infinite dilution vs. temperature were in agreement with the Arrhenius equation. The variance in the diffusion coefficients at infinite dilution of the three small molecule solvents was analyzed according to the differences in molecular mass.

Wettability of Surface with Nano-structures Studied by Using Molecular Dynamics Simulation

CAO Bing-Yang, CHEN Min, GUO Zeng-Yuan

2005, 26(2):  277-280. 

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The molecular dynamics simulation method was applied to investigate the wettability of argon nano-droplets on platinum and other model solids. The contact angle and spreading characteristics of flat and triangle-array nano-structure surfaces were obtained. For the hydrophilic fluid-solid interaction, the homogeneous wetting took place between the droplet and the nano-structure surface, while the apparent contact angle was little affected due to the hysteresis. For the hydrophobic interaction, vapor-like phase appeared inside the nano-structure diastemata, and the wetting between the droplet and the nano-structure surface turned to be heterogeneous. Within the simulation scales, the contact angle increased with increasing the nano-structure size, and might even show surperhydrophobicity.

Special Properties of Oppositely Charged Polymer/Surfactant Composite Films on the Air/Water Interface

ZHAO Feng, DU Yu-Kou, YANG Ping, TANG Ji-An, LI Xing-Chang

2005, 26(2):  281-284. 

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Atomic force microscopy(FAM) and the surface pressure relaxation technique were employed to characterize the properties of oppositely charged polymer/surfactant complex films formed on the air/water interface. By the observation of AFM, it is shown that partially hydrated polyacrylamide(HPAM)/hexadecyltrimethylammonium(CTAB) complex films appear in the morphology of patch aggregates. Amphoteric HPAM/CTAB complexes are observed to form filbrelike structures. Salts in the subphase have an impact on the morphology of interface complexes. Furthermore, the surface pressure relaxation revealed that the conformational changes of interface complexes are directly related to the stability of the films.

Non-oxidative Aromatization of Methane by Using Propane as Co-reactant over Mo-Zn/HZSM-5 Catalyst

ZHENG Hai-Tao, LOU Hui, LI Ying-Hui, FEI Jin-Hua, HOU Zhao-Yin, XU Yan, WAN Shu-Bao, WANG Si-Han, ZHENG Xiao-Ming

2005, 26(2):  285-289. 

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The non-oxidative conversion of methane(C₁) into aromatic hydrocarbons by using propane(C₃) as co-reactant over x%Mo+6%Zn/HZSM-5 catalysts was studied. C₁ conversion was very high, reaching 29%₃5%. Selectivity of aromatic products reaches above 80% at 873 K and GHSV=3 L/(g·h) with n(C₁)/n(C₃)=1.0. The excellent conversion of C₁(34.8%) was obtained over 0.7%Mo+6%Zn/HZSM-5 catalyst at 873 K and n(C₁)/n(C₃)=1.0. The effects of time-on-stream and n(C₁)/n(C₃) on C₁ and C₃ conversion and the products distribution were analyzed in order to obtain information about C₁ incorporation into the aromatic products and the evolution of different species. C₁ incorporation was conclusively confirmed by the mass spectral analyses of aromatic products produced in a run with 13^CH₄, which shows a significant 13^C enrichment in the C₆H₆⁺, C₇H₈⁺ and C₈H₁₀⁺ fragments. The methane activation could result from its hydrogen-transfer reaction with alkenes. This process was hoped to provide a novel route for the chemical utilization of natural gas and refinery gas.

TDDFT-SOS Theoretical Studies on Nonlinear Optical Properties of Furan Homologues C₄H₄X(X=O, S, Se, Te)

QIN Chun-Sheng, YANG Guo-Chun, SU Zhong-Min, ZHU Yu-Lan, ZHOU Zi-Yan

2005, 26(2):  290-293. 

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The nonlinear optical properties were calculated for the furan homologues including furan(C₄H₄O), thiophene(C₄H₄S), selenophene(C₄H₄Se) and tellurophene(C₄H₄Te), by time-dependent density functional theory(TDDFT) combined with sum-over-states(SOS) method. The calculated results show that the substitution of the heteroatom with heavy atoms systematically increases the polarizability α and second hyperpolarizability γ. The values of α and γ calculated by B3LYP, BLYP, SVWN and X_α functionals are similar. The calculated results indicate that the C₄H₄X exhibits a small dispersion in a width frequent zone. It is more available to be used for NLO materials.

Density Functional Study of Magnetic Coupling Interaction in Dimeric Copper(Ⅱ) Complex with Hydrogen-bonded Bridges

SUN You-Min, WANG Ruo-Xi, LIU Cheng-Bu

2005, 26(2):  294-298. 

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Based on the density functional theory(DFT) combined with the broken symmetry(BS) approach, the magnetic coupling interaction in the hydrogen-bonded copper(Ⅱ) dimmer and the change of magnetic coupling constant with the change of the O-O distance were studied. The orbital analysis shows that the superexchange interaction in the hydrogen-bonded Cu(Ⅱ) dimmers comes from the overlap between the d_x²-y² orbital on Cu(Ⅱ) ions and p_x or p_y orbitals on O atoms, whereas the hydrogen bridges do not participate the magnetic coupling. The dependence of the magnetic coupling constant J value on the O-O distance can be expressed as an exponential function.

Direct Dynamics Studies on the Isomerization Reaction H₃PO→H₂POH

WANG Wen-Liang, WANG Wei-Na, LUO Qiong, FANG Yu, LI Qian-Shu

2005, 26(2):  299-303. 

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The isomerization reaction of H₃PO(1)H₂POH(trans)(2)H₂POH(cis) was studied by using the direct ab initio dynamic method. The optimized geometries and frequencies were calculated at the QCISD/6-311C⁺⁺G(d,p) level of theory for the reactant, products, and transition states as well as 18 selected points along the minimum energy pathway. In order to obtain more reliable energies, the single-point calculations were carried out at the QCISD(T)/6-311C⁺⁺G(2df,2pd) level of theory. The barrier of reaction(1), in which the hydrogen atom transfers from phosphor atom to oxygen atom, is more higher than that of reaction(2), the former is 250.0 kJ/mol and the latter is 12.3 kJ/mol. Therefore, reaction(1) is the rate controlling step of the isomerization reaction. The rate constants of reaction(1) were evaluated in the temperature range of 200-2000 K by the classical transition state theory, the classical transition state theory with Eckart tunneling model, the canonical variational transition state theory, and canonical variational transition state theory incorporating small-curvature tunneling correction, respectively. The fitted three-parameter expression from the CVT/SCT and TST/Eckart in the temperature range of 200-2000 K is k_CVT/SCT=2.747×10^-68 T^24.01exp(-1.0094×10⁴/T)s^-1 and k_TST/Eckart=1.423×10^-69 T^24.46exp(-1.0182×10⁴/T)s^-1, respectively. The results show that the tunneling effect is significant and the variational effect is small for the calculation of the rate constant.

A Theoretical Study on the Conductivity of Carbon Doped BNNT

ZHAO Jing-Xiang, DAI Bai-Qing, ZHANG Gui-Ling

2005, 26(2):  304-307. 

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From the changes in energy band, density of state(DOS) and the electronic structure calculated by the DFT/B3LYP method, the conductivity of carbon doped boron-nitride nanotube(BNNT), which is formed by C_C bond substituting B_N bond, was discussed. The results indicate that the substitution will strength the conductivity of the tube, and its semi-conductivity might be adjusted by controlling the substitution.

N-Benzylideneaniline-like Derivatives and Their Conformation

XU Hong, YU Zhong-Heng

2005, 26(2):  308-311. 

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To discern the driving force for distorting the geometry of NBA-like species, the relax potential energy scan was performed at the B3LYP/6-311G ^** level, for each molecule of 21 NBA-like species substituted with typical electron donor and/or acceptor at their benzylidene, aniline, and/or imine groups. In general, it is electron interaction, rather than nuclear repulsion between fragments, to distort a molecule away from its planar geometry, and their lowest total electronic energies occur in the geometries with the similar twist angles about 50°. Afterwards, the single point energies for 21 rotational geometries of each of two typical molecules 1 and 17 are calculated by using HF, BLYP, BVWN, B3LYP and MP2 at various Gaussian basis levels. Interestingly, STO-3G is accurate enough to understand the driving force for distorting NBA away from its planar geometry, but it is unreasonable to describe the intra-molecular hydrogen bond.

Molecular Dynamics Simulation of Calix[4]pyrrole in Different Solutions

CHEN Pei-Quan, SUN Hong-Wei, CHEN Lan, SHEN Rong-Xin, YUAN Man-Xue, LAI Cheng-Ming

2005, 26(2):  312-316. 

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The interaction between calix[4]pyrrole and different solvents, conformational interconversion of calix[4]pyrrole in different solutions and hydrogen bond interaction between calix[4]pyrrole and solvent molecules were investigated by a series of MD simulation. The interaction between calix[4]pyrrole and solvents is affected by the dipole moment of solvent molecules and the hydrogen bond interaction between calix[4]pyrrole and solvents. The formation of hydrogen bond between calix[4]pyrrole and solvents is the main factor for conformational intercoversion, and the dipole moment of solvent molecule is not important in the conformational intercoversion.

Electrochemical Properties and Electronic Energy Level of Phosphorescent Complexes (L)Re(CO)₃Cl(L=α,α-diamine)

LI Mao, ZHANG Ming, ZENG Ming, ZHANG Wu, YANG Bing, MA Yu-Guang, LI Ye-Zhi, YANG Li, FENG Ji-Kang

2005, 26(2):  317-320. 

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The electrochemical properties, the energy level and the band gap of a series of phosphorescent Re(I) complexes, (L)Re(CO)₃Cl(L=α,α-diamine) were studied by using cyclic voltammetry(CV) together with the UV-Vis absorption spectra, photoluminescence spectra and the self-consistent B3LYP quantum chemical calculation methods. Based on the results, the energy level of (L)Re(CO)₃Cl were obtained and the influencing rule of ligands was also drawn. (L)Re(CO)₃Cl complexes have a single oxidation peak and many reduction peaks. These peaks reflect the HOMO and LUMO energy level of (L)Re(CO)₃Cl complexes, which were made up of Re—Cl hybrid orbital and π^* orbital of diamine ligands, respectively. Compared with the results from the spectra, the band gap results of (L)Re(CO)₃Cl complexes calculated from CV mainly correspond to the triplet energy level.

In-situ UV and CD Spectroelectrochemistry Investigation of the Electrochemical Reduction Reaction Inducing Conformational Transition of Microperoxidase-11

JIANG Xiu-E, ZHANG Zhe-Ling, HUANG Wei-Min, LIU Xiao-Qiang, WANG Er-Kang, DONG Shao-Jun

2005, 26(2):  321-325. 

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Electrochemical reduction process of microperoxidase-11 was investigated by in-situ UV-Vis and CD spectroelectrochemistry methods with a long optical path thin layer cell. The spectra obtained were analyzed by singular value decomposition least square and double logarithmic analysis methods. The results showed that the electrochemical reduction induced the conformational transition of MP-11 from random coil to α-helix and provided an important information for understanding biological electron transfer mechanism coupled with conformational transitions.

Electrochemical Reduction Behavior of m-Nitrophenol on GC Electrode in Ionic Liquid [EMIM]Br

WANG Huan, YE Xiao-He, CHEN Li-Ming, LU Jia-Xing, HE Ming-Yuan

2005, 26(2):  326-329. 

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The direct electrochemical reduction of m-nitrophenol on GC electrode was investigated in ionic liquid(IL), 1-ethyl-3-methylimidazolium bromide([EMIM]Br) by using cyclic voltammetry and chronocoulometry. The diffusion coefficient D of m-nitrophenol in [EMIM]Br was 9.184×10^-7 cm²/s, while the transfer coefficient was 0.37. It can be proved that the reduction of m-nitrophenol on GC electrode was an irreversible process and the electrode reaction was diffusion-controlled by cyclic voltammetry.

PEO-LiClO₄-ZSM-5 Composite Polymer Electrolyte——Effect of ZSM-5 on the Selective Transference of Lithium Ion

XI Jing-Yu, MA Xiao-Mei, CUI Meng-Zhong, TANG Xiao-Zhen

2005, 26(2):  330-333. 

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A series of polyethylene oxide(PEO)-based composite polymer electrolytes(CPE), with different kinds of molecular sieves and montmorillonite as the filler, were obtained by solvent casting method. The effects of the filler on the lithium-ion transference number(TLi⁺) of the CPE were investigated by the method of AC impedance coupled with steady-state current techniques. The experiment results showed that the addition of all kinds of fillers could improve TLi⁺ and enhance the ionic conductivity of PEO-LiClO₄ at the same time. However, the highest TLi⁺ of 0.353 was recorded by using Li-ZSM-5 as the filler. The special two-dimension frameworks of the ZSM-5, which might let the cation Li⁺ to pass through and prevent the passing of the anion ClO-₄, could be used to explain the enhancement of TLi⁺ induced by Li-ZSM-5. High TLi⁺ and RT ionic conductivity ensured the use of PEO-LiClO₄-ZSM-5 as the electrolyte materials for all solid-state rechargeable lithium ion batteries.

Plant Acid Salt Inhibitor and Its Inhibiting Mechanism

ZHAO Di-Shun, LIU Hui-Ru, XU Zhi-Ce, PANG Deng-Jia, WANG Chun-Fang

2005, 26(2):  334-336. 

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The selected inhibitor of plant acid salt has a higher inhibiting efficiency on the basis of the study of inhibitor in zinc-manganese battery. The experimental results show that the inhibiting effect is the best when its mass fraction is 0.01%. The inhibiting mechanism was studied by measuring cyclic voltammogram and the circuit impedance curves. The result shows that the inhibiting mechanism of plant acid salt is a chemical adsorption process.

Structure, Stability and Electron-counting Rule of[B₂₀H (18)]^n-(n=0,2,4,6) Anionic Isomers

ZHANG Jian, ZHANG Ming-Yu, ZHAO Yuan-Yuan, CHEN Bao-Guo, SUN Chia-Chung

2005, 26(2):  337-339. 

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Various isomers of [B₂₀H₁₈]^n-(n=0,2,4,6) anions are investigated by using the DFT method at B3LYP/6-31G^* level to obtain the optimized geometries and the order of stability. The optimized bond lengths are consistent with the available experimental values. The calculated vibrational frequencies are all real, so all of these isomers should be stable structures where [a²-B₂₀H₁₈]^2-(3), [a²-B₂₀H₁₈]⁰(8) and [a²-B₂₀H₁₈]^6-(9) predicted in this paper were not discovered. Moreover, the analyses on counting of skelet al bonding electrons show that isomers 1—7 obey the electronic requirement predicted by the mno rule, but isomers 8 and 9 are two exceptions.

Synthesis of Ionic Liquids Based on the N-Methyl-N-allyl Morpholinium Cation

ZHANG Qing-Shan, LIU Ai-Xia, GUO Bing-Nan, WU Feng

2005, 26(2):  340-342. 

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The preparation of a new family of ionic liquids via the reaction between N-methyl-N-allyl-morpholinium cations was reported for the first time, and BF-₄, PF-₆ and (CF₃SO₂)₂N^- [bis(trifluoromethanesufonyl)imide, TFSI^-]. The cation has an ether bond and is functionalized by allyl. The structure of these compounds were determined by ¹H NMR and elemental analysis. Some properties were also presented in this paper.

Synthesis of Cyclic Carbonates Catalyzed by Ionic Liquid Mediated ZnBr₂ Catalytic System

LI Fu-Wei, XIAO Lin-Fei, XIA Chun-Gu

2005, 26(2):  343-345. 

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Ionic liquid mediated ZnBr₂ system could catalyze the chemical fixation of CO₂ with epoxides with a high selectivity(>98%) and TOF(5 580 h^-1) under mild reaction conditions and the catalyst could be reused five times almost without losing its catalytic activity and selectivity. Besides, the pure cis-cyclic carbonate of cyclohexene oxide was obtained over this catalyst system.

Electron Beam Curing of Epoxy Resin E-44

GAO Chun-Ling, GUO Dong-Zi, XIE Li-Qing

2005, 26(2):  346-348. 

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The critical parameters of electron beam to cure the epoxy resin E-44 were studied. The initiating efficiency of every photoinitiator increases with the increase of the absorbed dose. Diphenyl iodonium hexafluoroantimonate being the photoinitiator has a higher initiating efficiency, whose optimal quantity is 3%. The curing degree of the system is improved continuously with the increments of the photoinitiator content when the absorbed dose and the dose rate are fixed. The curing degree increases with raising dose rate obviously when the absorbed dose are fixed.

DNA-modified Porous Polysulfone Microspheres for Selective Removal of Endocrine Disruptors

ZHAO Chang-Sheng, YANG Kai-Guang, Motoyoshi Nomizu, Norio Nishi

2005, 26(2):  349-352. 

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DNA was regarded as a naturally occurring biopolymer, and was used to modify polysulfone(PSf) porous microspheres. The DNA-modified microspheres are used to selectively remove endocrine disruptors and heavy met al ions. The DNA-modified PSf microspheres can be prepared using two methods: DNA-blended PSf microspheres and DNA surface modified PSf microspheres. The microspheres, made in the two ways above, are stable in water while they are hydrolyzed under acidic and alkaline conditions. The DNA-modified porous PSf microspheres can effectively remove biphenyl, dibenzofuran and dibenzo-p-dioxin, and can selectively accumulate and remove heavy mental ions.

Complex and in vitro Release of Methotrexate-PAMAM Dendrimer

YE Ling, JING Xiao-Zhou, YANG Hua, SU Jian-Ting, YUN Liu-Hong

2005, 26(2):  353-355. 

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We investigated the interaction between G5.0 PAMAM and methotrexate(MTX) drug molecules by ¹³C NMR, and it has been proven that the interaction is occurring between the PAMAM amine functional groups and the MTX carboxyl groups. UV-Vis study showed each G5.0 PAMAM could conjugate up to 27 MTX molecules. The release of MTX from complex is much slower than that of free MTX at pH=7.4, 10 mmol/L Tris-HCl buffer. The presence of 0.02 mol/L NaCl in buffer increases the release rate of MTX from the complex, which further defines the interaction between PAMAM and MTX.

Effects of Chain Length and Concentration of Block Copolymer on the Phase Separation of A/B/A-B System by TDGL Simulation

YE Xiang-Gui, SUN Zhao-Yan, AN Li-Jia

2005, 26(2):  356-361. 

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The free energy functional for the time dependent Ginzburg-Landau equation were obtained by means of Flory-Huggins free energy. The couplings between different order parameters and the chain lengths were included. The phase behavior of A/B/A-B system at different A-B chain lengths and concentrations were simulated. For the same chain length and concentration of homopolymer A and B, there is an optimum chain length of diblock copolymer to minimize the mean domain size. At the fixed chain length of the homopolymer and diblock copolymer, the structures of the mixture are greatly different when the concentration of diblock copolymer is different. Furthermore, the phase domain structures are different at different concentrations of homopolymer A and B.

Formation of Cavitated Structure of Block Copolymer Micellar Thin Film

ZHAO Jun-Chai, WANG Qiang, QIAO Cong-De, JIANG Shi-Chun, JI Xiang-Ling, AN Li-Jia, JIANG Bing-Zheng

2005, 26(2):  362-365. 

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The cavitation of block copolymer micellar thin films was studied by atomic force microscopy(AFM). The results demonstrate that the formation of this structure is strongly dependent on the number of the hydrogenous ion of the used acids, i.e. unitary, binary or other acids. Only using unitary acids can we obtain the cavitated structure. We explained the possible mechanism of the formation of this structure. It was considered that when unitary acids(HCl, HNO₃ or HAc) were used, they could enter into the P4VP domains and P4VP would be protonated, the swelling occurred and this made the volume of the P4VP domain increasing and then the thin shells of glassing polystyrene that confined the P4VP domains would be ruptured. When binary or other multiacids were used, the two or more hydrogenous ions can protonize the adjacent P4VP domains. So the ionic cross-linking between the P4VP and the multiacid efficiently inhibited the volume expansion of P4VP domains, the cavitated structure did not appear. Using selected solvent vapor or unitary acids we can obtain the cavitated structure, but whether the essence of two methods is the same or not needs to be proved further by experiment.

Preparation and Characterization of Superparamagnetic Polymer Microspheres

AN Li-Juan, LI Zhao-Qiang, XU Wei, CHEN Xin-Fang, YANG Bai

2005, 26(2):  366-369. 

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The magnetic nanoparticles were synthesized by the chemical coprecipitation of ferrous chloride and ferric chloride. The obtained magnetic nanoparticles were coated with double surfactant. The magnetic polymer microspheres were prepared by emulsion polymerization by using styrene and methylacrylic acid as the monomer with the existence of magnetic fluid. TEM, FTIR, XRD, TGA and SQUID were used to characterize the size, component, magnetic percentage and magnetic property of the obtained microspheres. The content of magnetite in microspheres is 23.6%; The average size of magnetic fluid was 10 nm, and that of magnetic microsphere was 130 nm. The magnetic fluid and magnetic microsphere were found to show a superparamagnetic property.

Preparation and Characterization of Novel NBR/PVC Alloy Crosslinked by Coordinate Bonds

LI Hui, SHEN Fei, WU Chi-Fei

2005, 26(2):  370-372. 

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The most common way of rubbers for obtaining high performance is vulcanization, by which the linear macromolecules are crosslinked into three-dimensional networks. The rubbers vulcanized by covalent bonds are serious pollutants. There has been an increasing interest in the novel rubbers crosslinked by supramolecular interactions such as hydrogen bonds and ionic bonds because of the supramolecular interactions are reversible and the crosslinked materials are likely to be recycled. In this paper, a series of novel NBR/PVC materials crosslinked with CuSO₄ by coordinate bonds were prepared for the first time, and the produced materials have excellent mechanical properties. In this system, the coordinate bonds formed in situ during the heat press process. XPS and SEM results prove that there are really crosslinks by coordinated bonds between the polymers and the CuSO₄ particles. The characterizations of mechanical properties, crosslink densities and the temperature of glass transition all showed that degree of crosslink and the performance of the coordinated materials could be adjusted controllably.

Preparation of a Novel Thermosensitive and Biodegradable Microgel Particles

ZHU Wen, ZHANG Ying, WANG Biao-Bing, DING Jian-Dong

2005, 26(2):  373-375. 

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A novel biodegradable and thermosensitive microgel particle was prepared via suspension polymerization of a well-designed biodegradable macromonomer. The macromonomer is composed of amphiphilic block copolymer PEO-PPO-PEO, oligo(ester) and acryloyl end groups. Ammonium persulfate was employed as the initiator and N,N,N',N'-tetramethylethylene-diamine as the accelerator. The resultant hydrogel particles were confirmed to be reversely thermosensitive as well as biodegradable.

Self-assembly and Luminescence Property of Met allodendritic Supramolecule Consisting of a Functional Cryptand Core and Six Digold(Ⅰ) Branches

YU Shu-Yan, ZHANG Zhong-Xing, LI Hui, HUANG Hai-Ping, ZHANG Rong-Ben, ZHANG Jian-Ping, CUI Yu-Xin

2005, 26(2):  376-378. 

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Self-assembly of a functional cryptand core(1) having six dithiocarbamate groups and (dppm)Au₂Cl₂ in methanol followed by the addition of excess NH₄PF₆ affords a novel met allodendritic supramolecule(2). This dendritic supramolecule was characterized by NMR, MS, XPS, IR, UV-Vis, luminescence spectra and elemental analyses. The results show the concentration-dependent absorption and luminescent properties in acetonitrile solution for the title compound, which may be closely related to the intramolecular and intermolecular aggregation of digold(Ⅰ) branches through Au(Ⅰ)…Au(Ⅰ) interactions.

Gold Nanoparticle Coated Polypyrrole Nanotubule and Its SERS Effect

HE Yong-Hong, YUAN Jin-Ying, SHI Gao-Quan, WU Pei-Yi, WANG Xiao-Lin

2005, 26(2):  379-381. 

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A method of fabricating gold nanoparticle coated polypyrrole(PPy) tubules was developed by coating citrate-reduced gold nanoparticles on polypyrrole tubule templates. The PPy tubules were grown uniformly with a diameter of 200 nm, which is in agreement with that of the pore size of the microporous polycarbonate(PC) membrane template. The Au particles formed by citrate reduction can be deposited on the surface of the PPy tubules. Electrostatic interaction between gold nanoparticles and PPy tubules was used as a driving force for this assembly process. The TEM image shows that a submonolayer coating of the particles was formed.The Au nanoparticle coated PPy tubules was applied to hold and analyze trace molecules as signal-enhancing cuvettes for Raman spectroscopy. Their SERS-activity was tested with Rhodamine B. In contrast with the neat PPy tubule, the Raman scattering of trace Rhodamine B on the Au nanoparticle-coated tubule was enhanced by a factor of 105. This work develops a cheap and convenient method to fabricate gold nanocrystal coated PPy tubule and its application as fabrication of Raman signal enhancing cuvette.

Conductive Properties of Multiwalled Carbon Nanotubes Filled High-density Polyethylene Composites

LI Wen-Chun, SHEN Lie, ZHENG Qiang

2005, 26(2):  382-384. 

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Conductive properties of multiwalled carbon nanotubes(MWNTs) filled high-density polyethylene(HDPE) composites prepared by melt blending were studied. The results showed that as the MWNTs concents reach to 3%(mass fraction), the electrical conductivity of the composites changes from insulator to semiconductor, possessing resistivtiy of 10¹⁰ Ω·cm. While as the MWNTs concents reach to 5%, the composites become a good conductor. The resistivity-temperature characteristic of the composites exhibits that with the increasing of the temperature, the resistivity of the composites first decreases, while increases abruptly when the temperature approaches melting point(t_m) of the matrix, indicating an existence of the negative temperature coefficient(NTC)-positive temperature coefficient(PTC) effect. It should be noted that this phenomenon can not be found in polymer-based composites filled with other conductive particles, such as carbon black, graphite, carbon fiber.

Preparation of Cu(core)/PVA(shell) Nanoparticles from Electrospinning to Electrospray Ionization

HAO Xiu-Feng, LI Zhen-Yu, LI Dong-Mei, WANG Ce

2005, 26(2):  385-387. 

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We present an electrospray ionization technology(ESI) to fabricate Cu-core/PVA-shell nanoparticles. The transition of nanofiber-to-nanoparticle is achieved by adjusting the mass fraction of PVA shell material containing Cu nanoparticles.

Preparation of Comb-like Block Polymer Hydroxy-capped Poly(ethylene glycol)methacrylate with High Density via Atom Transfer Radical Polymerization

LI Xiao-Lin, JI Jian, SHEN Jia-Cong

2005, 26(2):  388-390. 

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A novel hydroxy-capped comb-like block polymer, poly[poly(ethylene glycol)](HCPEG), was prepared via atom transfer radical polymerization(ATRP) of α-methylacryloyl-ω-hydroxyl-poly(ethylene glycol). The polymerization kinetics of the PHPEGMA was studied by gel permeation chromatography and ¹H NMR. The semilogarithmic plot of monomer conversion vs. reaction time increases linearly before the conversion is up to more than 70% and the number-average molecular weights(M_n) by GPC increased linearly with increase of the monomer conversion up to 100%, while the polydispersity index remained fairly narrow with M_w/M_n<1.2.

Structures and Morphology of PET/PEN/DBS Blends

LI Gui-Juan, LI Yi, SHI Xiu-Min, DAI Guo-Xing, CHEN Yan-Mo, ZHOU En-Le

2005, 26(2):  391-393. 

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DSC, WAXD and POM were performed on the structures and morphology of a blend system being composed of PET, PEN and nucleating agent(DBS). It is concluded that the crystallization of the blends is dependent on the contents of PET and the nuclenting agent, which affect the morphology of the blends. Under certain conditions, the blends show a complex extinction pattern, with the black cross extinction accompanying black homocentric zone and fireworks scattering form, rather than that of the common spherulite.

Aerobic Oxidation of Thiophenol Catalytzed by Co(Ⅱ) Tetrakis(n-propyl-oxycarbonyl)phthalocyanine in Bilayer Membrane of Vesicle

SONG Xi-Ming, ZHANG Dan, CHANG Xiao-Hong, ZHANG Li, ZHANG Xiang-Dong, LIU Qi-Tao

2005, 26(2):  394-396. 

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The oxidation of thiophenol(RSH) to phenyl disulfide catalyzed by Co(Ⅱ) tetrakis(propyl-oxycarbonyl)phthalocyanine[CoPc(COOC₃H₇)₄] in the presence of molecular oxygen was studied in synthetic bilayer membrane of vesicle, which is composed of hexadecyl 2-hydroxy-3-chloropropyl phosphate, SDS micelle, ethanol and benzene respectively. The catalytic activities followed the order of CoPc(COOC₃H₇)₄ in the bilayer membrane>ethanol>benzene, and in the bilayer membraneSDS micelle. UV-Vis spectroscopic studies reveal that the catalytic oxidation proceeds through RS--CoPc-O₂ intermediate. The catalytic activity of CoPc(COOC₃H₇)₄ in the bilayer membrane of vesicle higher than that in the other media is considered to be attributable to the disaggregation of CoPc(COOC₃H₇)₄ incorporated into the bilayer membrane and the easier H+ dissociation of RSH on the polar surface of the bilayer membrane bordered by bulk aqueous phase.