Chemical Research in Chinese Universities

Content of Chemical Research in Chinese Universities Vol.23 No.2(2007)

2007, 23(2): 0-0. doi:

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Hydrothermal Synthesis, Crystal Structure, and Characterization of a Novel Terbium(Ⅲ) Coordination Polymer Bridged by 5-Sulfoisophthalate Trivalent Anions

YUAN Ji-xin , XIONG Jing

2007, 23(2): 123-126. doi:

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Hydrothermal reaction of terbium(Ⅲ) chloride with 5-sulfoisophthalic acid monosodium salt and 1,10-phenanthroline(phen) at 415 K resulted in the formation of a novel coordination polymer, [Tb(sip)(phen)(H₂O)]_n(sip=5-sulfoisophthalate trivalent anion) with a three-dimensional network structure. Each centrosymmetrically related pair of terbium ions are linked by two sip anions, forming a binuclear unit, and each binuclear unit links to four adjacent tetranuclear units, extending a two-dimensional hybrid layer at crystallographic bc plane. On the other hand, every three-terbium ion is connected by three sip anions, generating a trinuclear ring, and the trinuclear ring connects six neighboring trinuclear rings to produce another two-dimensional layer at crystallographic ab plane. Moreover, each sip anion acts as a pentadentate bridge, interconnecting two different types of layers to yield a novel three-dimensional framework.

Enhancing Isolated Ti(Ⅳ) Framework Sites in HMS

YU Wei-hua, ZHOU Chun-hui, NI Zhe-ming , GE Zhong-hua

2007, 23(2): 127-130. doi:

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Ti-HMS materials were prepared by grafting titanocene onto the inner walls of hexagonal mesoporous silica(HMS). The materials were characterized via powder X-ray diffraction, N₂ adsorption-desorption isotherms, diffuse reflectance UV-Vis spectroscopy, and thermo-gravimetric analysis. The template of HMS was removed by calcination, ethanol-extraction, and ethanol-extraction followed by hydrolysis. The available grafting sites of OH groups depend on the different template removal methods of HMS. Ethanol-extraction followed by hydrolysis favors site-isolated Ti atoms in HMS. The catalytic performances of Ti-HMS materials were tested in the oxidation of 4-tert-butyltoluene with aqueous hydrogen peroxide. Ti-HMS prepared from HMS via the processing of ethanol-extraction followed by hydrolysis as support gave a maximum conversion of 7.5% and a complete selectivity to 4-tert-butyl-benzaldehyde, and showed a higher activity compared with those prepared by calcination and ethanol-extraction.

Effect of Polyaniline as Hole-Acceptor and Energy-Acceptor on the Photoluminescence of CdSe

ZHUANG Hong , LIU Jing-bo , ZENG Qing-hui , KONG Xiang-gui

2007, 23(2): 131-134. doi:

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The results of interaction between CdSe quantum dots and polyaniline were reported. Polyaniline effectively decreases the emission of CdSe quantum dots, and the CdSe luminescence lifetime is decreased by the addition of polyaniline. The mechanism of the emission observed in CdSe is assumed to result from the energy transfer and from the combination of surface-trapped electrons and holes energy is transferred from CdSe to polyaniline, and polyaniline occupies the hole sites.

Synthesis and Purification of Porphyrin-Schiff Base Using Ethyl Vanillin

WANG Dong , SU Lian-jiang , CHENG Xiu-li , SUN Er-jun , SHI Tong-shun

2007, 23(2): 135-137. doi:

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A novel porphyrin-Schiff base was synthesized via the condensation of 5-(4-aminophenyl)-10,15,20-triphenylporphyrin and ethyl vanillin. After analyzing the level of purification of the porphyrin-Schiff base, it was successfully separated. This porphyrin-Schiff base was characterized by using UV-Vis, IR, ¹H NMR and MS spectroscopy.

CdS Quantum Dots as Fluorescence Probes for Detection of Adriamycin Hydrochloride

LIAO Qie-gen, LI Yuan-fang , HUANG Cheng-zhi

2007, 23(2): 138-142. doi:

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Water-soluble CdS quantum dots(CdS-QDs) capped with thioglycolic acid were easily prepared, and a detection method of adriamycin was presented based on the fluorescence quenching of CdS-QDs. It was found that a complex could be formed between cetyltrimethyl ammonium bromide(CTAB) and CdS-QDs by using electrostatic interaction in Britton-Robinson(BR) buffer at pH=7.00, and the strong fluorescence emission of the complex was observed at 500 nm when the complex was excited at 378 nm. The presence of adriamycin, however, could strongly quench the fluorescence through hydrophobic interaction. The overall quenching percentage as a function of adriamycin concentration matches the Stern-Volmer equation very well. These properties make CdS-QDs a potential fluorescence probe for the detection of adriamycin. The detection limit(3σ) of adriamycin is approximately 10^-9 mol/L.

Determination of Ultratrace Amounts of Copper(Ⅱ) in Water Samples by Electrothermal Atomic Absorption Spectrometry After Cloud Point Extraction

CHEN Jian-guo , CHEN Heng-wu , CHEN Shao-hong , LIN Li , ZHONG Ying-ying

2007, 23(2): 143-147. doi:

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A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry(ETAAS) after cloud point extraction(CPE). 1-(2-Pyridylazo)-2-naphthol was used as the chelating reagent and Triton X-114 as the micellar-forming surfactant. CPE was conducted in a pH 8.0 medium at 40 ℃ for 10 min. After the separation of the phases by centrifugation, the surfactant-rich phase was diluted with 1 mL of a methanol solution of 0.1 mol/L HNO3. Then 20 μL of the diluted surfactant-rich phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconcentration. The linear dynamic range of the copper mass concentration was found to be 0\_2.0 ng/mL, and the relative standard deviation was found to be less than 3.1% for a sample containing 1.0 ng/mL Cu(Ⅱ). This developed method was successfully applied to the determination of ultratrace amounts of Cu in drinking water, tap water, and seawater samples.

Dynamic Microwave-assisted Extraction of Flavonoids from Radix Scutellariae

YOU Jing-yan, ZHANG Hua-rong, DING Lan, XIAO Ting-ting, ZHANG Han-qi , SONG Da-qian

2007, 23(2): 148-153. doi:

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Dynamic microwave-assisted extraction(DMAE) of flavonoids from Radix Scutellarie was described in this article. A TM₀₁₀ microwave resonant cavity was used as the energy coupler. Several parameters of DMAE, including concentration, flow rate, volume of the extraction solvent, and irradiation power, were optimized. The extraction was performed under the optimum conditions for the extraction of total flavonoids. The total flavonoids were determined by UV-Vis spectrophotometry. The main bioactive components, including baicalin, baicalein, and wogonin, were determined by HPLC. The extraction yields of the flavonoids obtained by DMAE were compared with those obtained by pressurized microwave assisted extraction(PMAE), ultrasonic extraction(UE), soxhlet extraction(SE), and reflux extraction(RE), and these results indicate that DMAE is a good alternative method for the extraction of flavonoids from Radix Scutellarie.

Photooxidation of Furfural with Phthalocyanine-sensitized TiO₂ Particle Under Xenon Lamp

KANG Chun-li , LU Yu , GUO Ping , ZHANG Fan , YU Hong-bing , LIN Xue-yu

2007, 23(2): 154-158. doi:

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Copper phthalocyanine was selected as the photosensitizer to sensitize TiO₂ in this experiment with furfural as the target pollutant. The composite catalysts(TiO₂/CuPC) obtained showed a great activity under a xenon lamp. By experiments, the optimal preparation conditions of the composite catalysts were set as follows: the CuPC loading mass fraction was 1.5%, the mass fraction of acetylacetone was 0.3%, and the stirring time was 10 h. UV-Vis diffuse reflectance spectra, XRD, and BET were used to characterize the properties of the composite catalysts, which showed that after loading CuPC on TiO₂, the composite catalyst retained the same crystal structure as pure TiO₂ and the wavelength range of its absorption spectrum was broadened to 600—700 nm while its surface area was smaller than that of the pure TiO₂. Under the optimal conditions, 20 mg/L furfural solution was degraded by nearly 90% and TOC by about 70%. When the catalyst was reused 6 times, the activity of the catalyst was still retained by about 75%.

Syntheses, Structures, and Blue Luminescent Properties of 2,6-Bis-(benzimidazolyl)Pyridine and Its Mercury Complex

LIU Xiao-ming , MU Xiao-yue , XIA Hong , SU Qing , YE Ling , CHEN Chao , GAO Wei , MU Ying

2007, 23(2): 159-162. doi:

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A novel blue luminescent mercury(Ⅱ) complex of 2,6-bis(benzimidazolyl)pyridine(L) was synthesized. In solid state, this complex has the formula [Hg(L)Cl₂]·2DMF(1). The molecular structures of both the ligand and the complex were determined by using single-crystal X-ray diffraction. Crystallographic studies of the mercury(Ⅱ) complex reveal that the complex possesses a five-coordinated geometry that can be best described as a distorted trigonal-bipyramidal. The luminescent properties of ligand L and complex 1 both in solution and in solid state were also studied.

Amide Ionic Liquids(AILs)/L-Proline Synergistic Catalyzed Asymmetric Mannich Reactions

LIU Bao-you , ZHAO Di-shun , XU Dan-qian , XU Zhen-yuan

2007, 23(2): 163-168. doi:

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Amide ionic liquids(AILs)/L-proline synergistic catalyzed Mannich reactions of isovaleraldehyde, methyl ketones, and aromatic amines were carried out in moderate to high yields(up to 96%) and high stereo selectivities(>99% e.e.). The products were easily isolated by extraction; and the catalyst system was readily recycled at least thrice without significant loss of efficiency. The scope of the substrates was studied and the interpretation of the manifest improvement of the reaction rates and enantio-selectivity of the novel catalyst system was speculated.

Basic Ionic Liquid: A Reusable Catalyst for Knoevenagel Condensation in Aqueous Media

GAO Guo-hua, LU Liang, ZOU Ting, GAO Jin-bao, LIU Ye , HE Ming-yuan

2007, 23(2): 169-172. doi:

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An efficient, environmentally friendly procedure was developed for the condensation of aldehydes/ketones and activated methylene compounds with basic ionic liquid as the catalyst in water. This basic ionic liquid catalyst has a very high activity for Knoevenagel condensation to give the corresponding products in 70%—97% isolated yields under mild conditions. The basic ionic liquid catalyst in aqueous system can be reused for six times without any significant loss of activity.

Transesterification of Ethylene Carbonate with Dimethyl Terephthalate over Various Metal Acetate Catalysts

ZHANG Dan , JIA Shu-yong , WANG Yue , YAO Jie , WANG Gong-ying

2007, 23(2): 173-175. doi:

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The reaction between ethylene carbonate and dimethyl terephthalate was carried out for the simultaneous synthesis of dimethyl carbonate and poly(ethylene terephthalate). This reaction is an excellent chemical process that is environmentally friendly and produces no poisonous substance. The metal acetate catalysts used for this reaction are discussed in detail. Lithium acetate dihydrate was found to be a novel and efficient catalyst for this reaction. Compared with other metal acetates, lithium acetate dihydrate can attain a maximum catalytic activity at a lower concentration. When the reaction was carried out under the following conditions: the reaction temperature from 230 to 250 ℃, molar ratio of ethylene carbonate(EC) to dimethyl terephthalate(DMT) 3:1, reaction time 3 h, and a catalyst amount of 0.4%(molar fraction to DMT), the yield of dimethyl carbonate(DMC) was 79.1%.

Synthesis and Primary Research on Antitumor Activity of Three New Panaxadiol Fatty Acid Esters

ZHANG Chun-hong , LI Xiang-gao , GAO Yu-gang , ZHANG Lian-xue , FU Xue-qi

2007, 23(2): 176-182. doi:

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For making use of Ginseng resources that exhibit an antitumor activity and for finding new anticancer drugs, three new fatty acid ester compounds: 3β-acetoxy panaxadiol(Ⅰ), 3β-palmitic acid aceloxy panaxadiol(Ⅱ), and 3β-octadecanoic acid aceloxy panaxadiol(Ⅰ, Ⅱ, and Ⅲ) were synthesized with panaxadiol, diacetyl oxide, palmityl chloride and stearyl chloride, and their structures were determined via MS, ¹³C NMR, IR, TLC, and so on. The molar yields of the three compounds are 75.14%, 79.08%, and 72.57%, respectively. Meanwhile, the antitumor activity of the three new panaxadiol fatty acid ester derivatives and panaxadiol was compared by using the method of MTT. Tumor cell used was Vero cell line. Positive control was 5-FU, blank was an RPMI1640 culture medium, negative control was an RPMI1640 culture medium and the solvent for drugs to be tested. Compound Ⅰ has the strongest antitumor activity followed by panaxadiol; compounds Ⅱand Ⅲ have similar and weakest antitumor activities. Furthermore, the antitumor activities of the panaxadiol fatty acid ester derivatives show positive correlation with the concentration of the test group, but show no relationship with the molecular weight of fatty acid. The methods that are used to synthesize the three compounds with high yields and strong antitumor activities are simple and show a great potential for meeting the needs of industrial manufacture of these drugs.

nSrDNA Appraisal of High Yield Flocculant Compound Bacteria and Their Application Effect

ZHANG Lan-ying , ZHANG Yu-ling , YAO Jun

2007, 23(2): 183-186. doi:

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High effect flocculant compound bacteria were screened out with the product bacteria of flocculant in soil. Their system appraising study shows that two were actionomyces and the other was microzyme among the three bacteria. According to nSrDNA, the three bacteria were marked at a molecule level and the system growth tree was established, ensuring the position of compound bacteria at the molecule level. The purificant which was made of the compound bacteria has spreading value because of its excellent clearing effect for organic and inorganic polluted water.

Specific Proteins in the Indirect Somatic Embryogenesis of Freesia Refracta

GAO Xiang , HUI Yue-jun , XUE Yi-qun , FU Yang , AO Man , WANG Li

2007, 23(2): 187-190. doi:

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Using the young inflorescence segments of Freesia refracta as explants, indirect somatic embryogenesis of somatic cells was induced in a N₆ medium supplemented with some exogenous hormones. SDS-polyacrylamide gel electrophoresis(SDS-PAGE) was used for the analysis of soluble proteins produced during the somatic embryogenesis of this plant. There are six polypeptides, which might play some roles in the process of somatic embryo development. Three polypeptides(45, 53 and 55 kD) were detected in the stages of embryogenic callus, globular embryoid, and embryoid with coleoptiles, except the embryoid with leaf. One polypeptide(83 kD) was specific for the stages of embryoid with coleoptiles and embryoid with leaf. One polypeptide(37 kD) was detected in the first two stages, namely, embryogenic callus and globular embryoid. One polypeptide(35 kD) was regularly synthesized in each stage, from embryogenic callus to embryoid with leaf.

Protein-protein Interaction Between Domains of PDZ and BAR from PICK1

XIAO Hong, SHI Ya-wei, WANG Li-li , YUAN Jing-ming

2007, 23(2): 191-195. doi:

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Two DNA fragments encoding PDZ domain(21—110 residues) and BAR domain(150—360 residues) from PICK1(1—416 residues) were amplified by PCR and then introduced into vectors, pET-32M and pMAL-c2X respectively to generate recombinant plasmids, pE-pdz and pM-bar. Having been separately transferred into the hosts E.coli BL21 and E.coli JM109, these two strains can express fusion proteins: His-tagged PDZ(PDZ domain) and maltose binding protein-BAR(MBP-BAR domain) respectively, as confirmed by both SDS-PAGE and Western blotting. The interaction between these two domains is dose-dependence, as identified by a pull-down test. Moreover, it has been shown from the ELISA analysis that the actual amount of PDZ bound to MBP-BAR-amylose beads reaches (16±0.5)%, as calculated by the molar ratio of PDZ to MBP-BAR. In addition, the interaction between BAR(bait) and PDZ(prey) in vivo was also examined with a yeast two-hybrid system.

Monitoring the Hydrolysis of Olive Oil Catalyzed by Lipase via Acid Value Detection

GAO Gui, ZHENG Liang-yu, ZHANG Zuo-ming, HAN Si-ping , CAO Sui-gui

2007, 23(2): 196-199. doi:

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Hydrolysis of olive oil catalyzed by Candida lipolytica lipase was investigated. The relative concentration of the components in the product was determined by using high performance liquid chromatography(HPLC). Furthermore, a novel rapid method to detect the hydrolytic process of olive oil was developed based on the relationship between the acid value and the relative concentration of the different components.

Assembly and Immunogenicity of Human Papillomavirus Type 16 Major Capsid Protein(HPV16 L1) in Pichia pastoris

LIU Da-wei, ZHANG Yu, YU Xiang-hui, JIANG Chun-lai, CHEN Yue, WU Yong-ge, JIN Ying-hua, NIU Jun, QU Ning, LIU Ming , KONG Wei

2007, 23(2): 200-203. doi:

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In this study, a recombinant Pichia pastoris expression system was developed to express HPV16 L1 protein that was driven by a strong AOX1 promoter. HPV16L1 gene was cloned into vector pPICZαB. HPV16 L1 protein expression induced by methanol was screened by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and Western blotting. The results indicate that the HPV16 L1 protein is secreted by the recombinant P. pastoris, and the purified HPV16 L1 protein can self-assemble into virus-like particles(VLPs), which show a good immunogenicity and induces high-titer antibody in mice.

Expression of Catalytic Domain of Protein Tyrosine Phosphatase 1B and Preparation of Its Polyclonal Antibody

SHI Dong-lei , DONG Hong-bo , ZHU Zhi-cheng , SUN Mei , SU Ji-quan , ZHANG Xing-yi , XU Yue-chi , FU Xue-qi

2007, 23(2): 204-207. doi:

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This study focuses on the expression of human protein tyrosine phosphatase 1B(PTP1B) catalytic domain(ΔPTP1B) and preparation of polyclonal antibody against ΔPTP1B. ΔPTP1B gene was PCR amplified with the cDNA of human PTP1B as the template, and cloned into the pT7 expression vector. The recombinant pT7-ΔPTP1B was expressed in E. coli Rosetta(DE3) host cells and purified. The antiserum was prepared by immunizing rabbit with purified recombinant ΔPTP1B. The polyclonal antibody against ΔPTP1B was purified by PVDF immobilized antigen affi-nity chromatography. ΔPTP1B was correctly cloned, expressed, and purified as confirmed by PCR, DNA sequence analysis, SDS-PAGE western blotting, and HPLC. The titer and sensitivity of the antibody were 1∶2500(volume ratio) and 0.1 ng, respectively. This study provides an important basis for further studying the biological function of PTP1B and its relationship with human diseases.

Metastable Equilibrium in Quaternary System Li₂SO₄+K₂SO₄+Li₂CO₃+K₂CO₃+H₂O at 288 K

SANG Shi-hua, YIN Hui-an , LEI Ning-fei

2007, 23(2): 208-211. doi:

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Metastable equilibrium solubilities and densities of the Li₂SO₄+K₂SO₄+Li₂CO₃+K₂CO₃+H₂O system at 288 K were determined experimentally by using the isothermal evaporation method. According to the experimental data, the metastable equilibrium solubility phase diagram was constructed. In the phase diagram, there are three invariant points, seven univariant curves, and five fields of crystallization: Li₂SO₄·H₂O, K₂SO₄, Li₂CO₃, K₂CO₃·3/2H₂O and K₂SO₄·Li₂SO₄. The double salt K₂SO₄·Li₂SO₄ was found in the metastable equilibria. Lithium carbonate(Li₂CO₃) has the smallest solubility in the quaternary system.

Effects of (BCO)_n Substituent on Claisen Rearrangement of Phenyl Allyl Ether

PEI Xiao-qin, JIAN Jian-feng , WU Hai-shun

2007, 23(2): 212-216. doi:

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Considering the isolobal analogy between two fragments CH and BCO, the calculations on the reactants, products, and transition states for the Claisen rearrangement of (BCO)_n-substituted phenyl allyl ethers at the B3P86/6-311+G** level was performed in this study. The transition states of (BCO)_n-substituted systems have looser and more structures with dipole nature. The substitutions of CH by BCO do favor the reduction of the free energies of activation and the enhancement of stabilization of both reactants and products. A Marcus theory and frontier molecular orbitals were used to separate the thermodynamic and intrinsic contributions to the activation energies.

Synthesis and Catalytic Activity of Copper(Ⅱ) Resorcylic Acid Nanoparticles

LI Yu , LIU You-zhi

2007, 23(2): 217-220. doi:

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Copper(Ⅱ) resorcylic acid(CuRes) nanoparticles were synthesized by using reactive precipitation method with resorcylic acid and blue copperas as the raw material in a rotating packed bed. The sample obtained was characterized by using X-ray diffraction(XRD), transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FTIR), thermo-gravimetric analyses(TG), and element analysis. In addition, the catalytic activity of CuRes nanoparticles on the thermal decomposition of nitrocellulose-nitroglycerine(NC-NG) was also determined via DSC. The results show that the spherical nanoparticles with a diameter of 20 nm were obtained in ethanol solution. The peak temperature of the thermal decomposition of NC-NG-CuRes decreases by 3 ℃ compared with that of normal CuRes, and the decomposition enthalpy is increased by 735 J/g, and therefore, it is reasonable to assume that CuRes nanoparticles have a better catalytic activity.

Insertion of O—H Bond of Rh(Ⅱ)-methylene Carbene into Alcohols: A Stepwise Mechanism More Plausible than a Concerted Mechanism

LIU Zhen-feng, WANG Yong, YUE Xian-fang , HAN Ke-li

2007, 23(2): 221-225. doi:

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The mechanisms of insertion of O—H bond of Rh(Ⅱ)-methylene carbene into methanol and ethanol were studied by using B3LYP functional both in gas phase and in CH₂Cl₂. The formation of free alcoholic oxonium ylides is found to be impossible. Alcoholic oxonium ylide are formed as the intermediates before both the stepwise and the concerted transition states of insertion of O—H bond of Rh(Ⅱ)-methylene carbene into methanol and ethanol. With regard to the mechanisms of insertion of O—H of Rh(Ⅱ)-methylene carbene into alcohols, analysis of the energy barriers of the two mechanisms indicate that the stepwise mechanism is more plausible than the concerted mechanism.

Adsorption and Vibration of O Atoms on Fe Low-index and Fe(211) High-index Surfaces

FENG Hui , ZHANG Xue-na , WANG Ze-xin , DIAO Zhao-yu , QIAN Zhao-sheng

2007, 23(2): 226-232. doi:

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The 5-parameter Morse potential(5-MP) of the interaction between oxygen atoms and iron surfaces was constructed. The adsorption and diffusion of O atoms on Fe low-index and Fe(211) high-index surfaces were investigated byusing 5-MP. All the critical characteristics of the system, such as adsorption site, adsorption geometry, binding energy, and eigenvalues for vibration, were calculated. The calculation results show that O atoms are located at the four-fold hollow site of the Fe(100) surface with an eigenvibration at 437 cm^-1. These results are in good agreement with the experimental and theoretical results obtained previously. With regard to the adsorption site of O—Fe(110) system, the authors of this study assume that the preferential adsorption state is the H₃ site and not the LB site, which is not in agreement with the experimental inferences obtained earlier. However, on the Fe(111) and Fe(211) surfaces, O atoms predominantly occupy the quasi-3-fold site.

Supercritical Fluid Extraction of Total Flavonoids from Leaves of Acanthopanax Senticosus Harms

LIU Chun-ming , ZHAO Ji-min , LI Hong-mei , SONG Feng-rui

2007, 23(2): 233-236. doi:

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In the present work, we focused our attention on the extraction of flavonoids from Acanthopanax Senticosus Harms with supercritical carbon dioxide. The influences of the use of ethanol as the modifier, pressure, temperature and extraction time on the extraction efficiency were investigated in order to achieve the best results. Moreover, the total flavonoid was determined via the spectrophotometry method at 500 nm with rutin as the standard. The results were compared with those obtained by the conventional extraction method.

Expression and Purification of Active Recombinant Human Nerve Growth Factor from Escherichia coli

HE Ling-bing , WANG Yan, , WANG Ge , CHEN Chao , CAO Shu-gui

2007, 23(2): 237-240. doi:

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In this paper a thioredoxin HisA/rhNGF fusion protein was designed to obtain more efficient expression and purification of rhNGF. Thioredoxin fusion proteins are usually soluble in E.coli cytoplasm and it also induces proper protein folding and disulfide bond formation in the fusion partner. The inclusion of HisA fragment facilitates efficient purification of the fusion protein by metal affinity chromatography. This strategy enables the expressed rhNGF not only avoid the problems associated with inclusion body denaturation and refolding but also maintain its biological activity.

Synthesis and Characterization of Thiacalix[4]arene Derivatives with Polymerisable Groups

GU Jin-ying , HU Xiao-jun , SHI Xian-fa , LI Yan-jun , QI Yong-lu , JI Liang-nian

2007, 23(2): 241-244. doi:

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In this study, first, polymerisable groups were introduced to the upper rim of thiacalix[4]arenes, which were then used as the special functional units to be incorporated into the polymeric backbone via copolymerization. Therefore, the resulting thiacalixarenes-containing polymers have molecular recognition abilities of the heavy metal ions such as Pb²⁺, Cd²⁺, and Hg²⁺. They are presumably used as the functional materials in the separation, enrichment, and removal of toxic heavy metal ions.

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