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Table of Content

    10 June 2014, Volume 35 Issue 6
    Content
    Review
    Research Advancements of Ordered Porous Metal Oxide Catalysts for the Oxidative Removal of Volatile Organic Compounds
    DENG Jiguang, HE Shengnan, XIE Shaohua, YANG Huanggen, LIU Yuxi, DAI Hongxing
    2014, 35(6):  1119-1129.  doi:10.7503/cjcu20131271
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    Ordered porous metal oxide catalysts(mainly including ceria, manganese oxides, cobalt oxides, iron oxides, chromia, perovskite-type oxides and supported noble metals or transition-metal oxides) investigated in recent years were reviewed. The catalytic behavior of these materials for the oxidative removal of typical volatile organic compounds(VOCs) was discussed. The design and development of novel catalysts with high performance and related technologies for VOCs removal were envisioned.

    Articles: Inorganic Chemistry
    Co-templates Synthesis and Characterization of a New Two-dimensional Co-containing Aluminophosphate [C4H11N]0.77[C4H12N]0.23[C3H12N2]2[H3O]2[Co0.23Al5.77P8O34]
    ZHU Jingran, LI Ke, YAN Yan, LI Xu, SONG Xiaowei
    2014, 35(6):  1130-1134.  doi:10.7503/cjcu20140206
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    In the presence of diethylamine and 1,2-diaminopropane, a new microporous cobalt-containing aluminophosphate compound [C4H11N]0.77[C4H12N]0.23[C3H12N2]2[H3O]2[Co0.23Al5.77P8O32](1) was synthesized. The structure of compound 1 was determined by single-crystal X-ray diffraction(XRD) analysis and further characterized by X-ray powder diffraction, thermogravimetric analysis(TG/DTA), inductively coupled atomic emission spectrometry(ICP-AES), CHN, Solid-UV-Vis spectrometry and scanning electron microscopy(SEM). It crystallizes in the triclinic system, space group P1-, with a=0.95029(19) nm, b=1.2689(3) nm, c=1.2987(3) nm, α=118.70(3)°, β=97.64(3)°, γ=99.72(3)°, V=1.3117(5) nm3, Z=1. The structure are built up from strict alternation of CoO4/AlO4 and PO3(=O) units. It contains 12-membered ring channel along [001] direction. The molar ratio of Co to Al is 1∶25.1. We also calculated the interaction energy and studied the co-template role of those two amines by the molecular dynamics method.

    Fabrication and Morphological Control of Hierarchical-structure ZnO
    SHEN Junhai, LI Jiajia, LI Liangchao, LI Juanbi, DING Yan
    2014, 35(6):  1135-1141.  doi:10.7503/cjcu20140083
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    The hierarchical-structure ZnO with different morphologies were fabricated by the hydrothermal method respectively using single and mixed zinc salts as the zinc source, sodium hydroxide as the precipitant, alanine and ionic liquid(IL) as the surfactant. The samples were characterized by XRD analysis, SEM observation, IR and UV-Vis spectrometry. The influential factors of the sample morphology were discussed, which included the zinc source(single, double and three zinc salts), the kind and dosage of ionic liquid, the dosage of alanine and temperature, etc. The modulation of anionic on sample morphology was speculated in the formation process of the ZnO with hierarchical structure.

    Synthesis and Structure of an Inorganic-organic Hybrid Zinc Phosphite
    WANG Xuelei, YAN Yan, WU Junbiao, ZOU Yongcun, ZHANG Chuanqi, LI Jiyang
    2014, 35(6):  1142-1145.  doi:10.7503/cjcu20131279
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    A 3D inorganic-organic hybrid zinc phosphite (C6N2H16)0.5ZnHPO3(ZnHPO-CJ15) has been hydrothermally synthesized. Crystal data for ZnHPO-CJ15 are as follows: monoclinic system, P21/c space group, a=1.19587 nm, b=0.82766(5) nm, c=0.77756(5) nm, α=90.00°, β=95.8370(10)°, γ=90.00°, V=0.76562(8) nm3 and Z=1. Single-crystal structure analysis reveals that the inorganic framework of ZnHPO-CJ15 is constructed by the connection of HPO3 pseudo-pyramids and ZnO3N tetrahedral to form 2D layers with 4- and 8-rings. The 1,6-hexanediamine molecules act as the pillars to link the adjacent zinc phosphite layers via N—Zn bonds to form 3D framework.

    Analytical Chemistry
    Cell Metabolomics Study of Hg(Ⅱ) Ion Effect on the Metabolic Pathways of Cells
    ZHANG Ruixing, LIU Shu, PI Zifeng, SONG Fengrui, LIU Zhiqiang
    2014, 35(6):  1146-1151. 
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    Mercury is harmful for human that can cause many diseases. But how it causes the disease and if any protective response from cell metabolism happens remain unclear till now. In this work, we analyzed the metabolomics of Hela cells treated with Hg(Ⅱ) ion by ultra-performance liquid chromatography-high resolution mass spectrometry. Totally 16 metabolites have been found to change significantly during Hg(Ⅱ) ion treatment by the facility of orthogonal partial least squares discriminant analysis(OPLS-DA). The results showed that Hg(Ⅱ) ion could impact many metabolic reactions including energy metabolism, phospholipid metabolism, fatty acid metabolism, amino acid metabolism and nucleic acid metabolism. But cells also had some stress reactions to protect themselves from Hg(Ⅱ) ion damage.

    Preparation and Evaluation of a Novel 6-mono-Nitrophenylamino-β-cyclodextrin Bonded SBA-15 Chiral Stationary Phase for HPLC
    ZHOU Rendan, LI Laisheng, CHENG Biaoping, NIE Guizhen, ZHANG Hongfu
    2014, 35(6):  1152-1160.  doi:10.7503/cjcu20140131
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    A mono-nitrophenylamino-β-cyclodextrin was synthesized and bonded to the surface of ordered mesoporous SBA-15 for high performance liquid chromatography(HPLC), which obtained a novel 6-mono-nitrophenylamino-β-cyclodextrin bonded SBA-15 chiral stationary phase(NCDSP). Its structure and morphology were characterized by infrared spectroscopy, elemental analysis, thermal gravimetric analysis, mass spectrometry, scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The basic chromatographic property of new NCDSP was evaluated and used for enantioseparations of chiral drugs such as β-blockers and dihydroflavanones. The fourteen kinds of β-blockers and six kinds of dihydroflavanones chiral drugs can be separated on NCDSP. The resolutions of metoprolol enantiomers and 2'-hydroxy flavanone enantiomers reached 1.75 and 5.21 within 20 min, respectively. By comparative study with PCDSP, some enantio-separation mechanisms of the new stationary phase were also discussed.

    Novel Aptamer-based Enzyme-linked Assay for the Detection of ATP
    ZHAO Qiuling, LIU Lingling, YANG Lina
    2014, 35(6):  1161-1165.  doi:10.7503/cjcu20140129
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    A novel aptamer-based enzyme-linked assay for the detection of adenosine triphosphate(ATP) was established based on the specific recognition of aptamer towards target and the efficient catalytic ability of horseradish peroxidase(HRP). Aptamer binding with targets caused that duplex DNA containing short chain DNA and aptamer dissociated and dissociated DNA was captured by another DNA immobilized on other plate through hybridization. A fluorescein isothiocyanate(FITC) was tagged on dissociated DNA, a HRP as signal transduction element was linked on microplate through specific interactions with anti-FITC-HRP and catalyzed methyenedianiline(TMB) substrate to produce color change. The detection of ATP was achieved by color change and absorbance change at 450 nm. This method has good selectivity for ATP recognition interfering from other proteins such as GTP, UTP and CTP and the detection can be carried in complex sample such as 10% and 50% serum. Experimental results show that there is a good linear relationship with ATP concentration ranged from 50 to 400 nmol/L, and the detection limit is 26 nmol/L.

    Sensor Based on Extracting Multidimensional Cataluminescence Signals for Idenpngying Toxic Gas
    CHEN Jinglin, CAO Xiaoan, LIU Yonghui, ZENG Jiayi, REN Keke
    2014, 35(6):  1166-1174.  doi:10.7503/cjcu20140098
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    A sensor system for idenpngying toxic gas was fabricated by extracting multidimensional cataluminescence(CTL) signal based on two kinds of catalytic sensitive materials. Under the optimal conditions of wavelength of 440 nm, temperature of 247 ℃ and flow rate of 240 mL/min, eighteen kinds of volatile organic compounds respectively generated CTL signal I1(the first order reaction signal) when each vapor passed through nano-Al2O3 or MgO, then residual gas from first reaction was regarded as a new reactant and continued to be oxidized on nano-Al2O3 or MgO, generating new CTL signal I2(the second order reaction signal). Moreover, for each organic gas, eight CTL signals could be obtained by changing the direction of the gas flowing through Al2O3-MgO, which formed the characteristic spectrum for each toxic compound. Different gases could be scienpngically and objectively idenpngied based on the principal component analysis(PCA). In addition, linear discriminant analysis(LDA) was utilized to idenpngy eighteen kinds of organic gas in different concentration(100, 300 and 500 mL/m3) with an accuracy of 100%. Furthermore, the sensor could achieve quantitative analysis with the detection limits below the occupational exposure limit of workplace(GBZ2.1-2007). Several kinds of common pollutants in the air had no interference on the detection of chosen toxic gases. Therefore, the sensor system may be capable to develop a micro-sensor with less sensing elements, good stability, conve-nient operation, rich information and strong recognition ability in real-life application.

    Fabrication and Characteristics Investigation of a Novel Nanosensor for Sulfuretted Hydrogen Operating at Room Temperature
    HUANG Xiaowei, ZOU Xiaobo, ZHAO Jiewen, SHI Jiyong, LI Zhihua
    2014, 35(6):  1175-1180.  doi:10.7503/cjcu20131161
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    A sulfuretted hydrogen sensor operating at room temperature based on pigment-sensitized TiO2 films was fabricated. TiO2 was prepared by sol-gel method and deposited on glass slides containing gold electrodes. The film was then immersed in a 2.5×10-4 mol/L ethanol solution of cyanidin to absorb the pigment. For characterization of texture, UV-Vis diffuse reflectance spectra, field emission scanning electron microscopy, sulfuretted hydrogen adsorption-desorption measurements and temperature, humidity measurements were adop-ted. The results demonstrate that the sol-gel layers show a high porosity, a slightly more compact material close to the substrate. The cyanidin-sensitized TiO2 nanosheets exhibit a clear red shift(50 nm) compared with cyanidin. The hybrid organic-inorganic formed film can detect sulfuretted hydrogen reversibly at room temperature. The sensitivity of the films increased almost linearly with increasing the concentrations of sulfuretted hydrogen(R2=0.939). The response time to increasing concentrations of the sulfuretted hydrogen is about 50~70 s, and the corresponding values for decreasing concentrations 160~180 s. At low humidity, sulfuretted hydrogen could be ionized by the cyanidin on the TiO2 film and thereby decrease in the proton concentration at the surface. The resistance response to sulfuretted hydrogen of the sensors was nearly independent on temperature from 10 ℃ to 50 ℃. This preliminary work proposes simpler and cheaper processes to fabricate gas sensor for room temperature applications.

    Organic Chemistry
    Synthesis, Antitumor Activity and DNA Binding of cridine-polyamine Conjugates
    LI Xiaoliu, MA Donglai, YANG Hailong, TAN Guanhai, DU Huiru, WANG Kerang, ZHANG Pingzhu, CHEN Hua
    2014, 35(6):  1181-1188.  doi:10.7503/cjcu20140066
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    A series of novel acridine-polyamine conjugates(ACP1-ACP6) was designed and synthesized. Their antitumor activities were evaluated against Leukemia cells(K562), human lung cancer cells(A549) and human cervical carcinoma cells(Hela) in vitro using MTT assay. The results showed that compound ACP2 exhibited potent anticancer activities, which was better than the positive control drug(cis-platin). Furthermore, their DNA binding properties were investigated by UV-Vis, fluorescence and circular dischroism(CD) spectroscopies and thermal denaturation experiment, which showed that the acridine-polyamine conjugates as the DNA intercalator had strong binding interaction with Ct-DNA.

    Syntheses and Antitumor Activities of Purine-sulfonamides Derivatives
    WANG Junhua, WANG Quande, DUN Yanyan, FANG Hao
    2014, 35(6):  1189-1198.  doi:10.7503/cjcu20131048
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    As a new type of purine derivative, Roscovitine exhibits good antiproliferative activities to different types of tumor cell lines and currently has been investigated in Phase Ⅱ clinical trial. Previous structure-acti-vity relationship studies on Roscovitine suggested that the modification on C2, C6 and N9 positions of purine could significantly influence the antitumor acitivities. In this work, a biologically active fragment benzenesulfonamide was introduced to purine C2 position and totally 25 new purine-sulfonamides derivatives were synthesized and evaluated antiproliferative activities in some tumor cell lines by MTT assay. The results show that the substitutions on C2, N6 and N9 positions of purine have a great impact on antitumor activity. And introducing phenylsulfonyl piperazine on C2 position of purine could obviously enhance antiproliferative activities. Among them, compound 17d shows similar inhibitory activities against PC-3, HCT116 and K562 tumor cell lines compared with Roscovitine.

    In-cell Selective Ultrasonic Electrosynthesis of Methyl Benzaldehyde Based on RBF Neural Network and Genetic Algorithm
    ZHANG Hui, HE Yuhan, TANG Duo, LI Yanwei
    2014, 35(6):  1199-1203.  doi:10.7503/cjcu20131043
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    Methyl benzaldehyde was synthesized via in-cell ultrasonic electrosynthesis with xylene mixture as raw material, Mn(Ⅲ) as oxidant and sulfuric acid as the electrolyte. The feasibility of the selective electrosynthesis of methyl benzaldehyde was discussed. The relation between experimental results(i.e. three methyl benzaldehyde isomer ratio of selective synthesis, current efficiency) and experimental conditions(i.e. xylene mixture concentration, sulfuric acid concentration and the current strength) were explored using radial basis function(RBF) neural network and genetic algorithm(GA)in the electrosynthesis process, and moreover, the prediction model was established. The mean squared error goal(Goal) and the spread of radial basis functions values(Spread) of the RBF neural network in prediction model were optimized by GA. Then electrochemical synthesis conditions, whenever 4-methyl benzaldehyde dominated, 2-methyl benzaldehyde and 4-methyl benzaldehyde dominated, or the current efficiency reached highest, were optimized by GA according to prediction model. In accordance with these conditions, the prediction results of model were given as follow: first, the percent content of 4-methyl benzaldehyde dominated was 90.01%; second, the percent content of 2-methyl benzaldehyde and 4-methyl benzaldehyde dominated was 80.38%; third, the percentage of 2-methyl benzaldehyde, 3-methyl benzaldehyde and 4-methyl benzaldehyde were 16.80%, 8.43% and 74.77%, respectively when the current efficiency reached the highest. The corresponding actual experiment results were 90.10%, 79.91% and 17.20%, 8.49%, 74.31%, respectively. The maximum relative error between prediction results and experiment results was less than ±2.24%. It showed that the model’s prediction results were in agreement with experimental results.

    Synthesis and Activity on Tyrosinase of Novel Chalcone Derivatives
    NIU Chao, LI Gen, , Haji-Akber AISA
    2014, 35(6):  1204-1211.  doi:10.7503/cjcu20131033
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    Ver-nohia anthelmintica L was endemic plant in Xinjiang, which was often used in the treatment of Vitiligo. It was believed that the chalcone compounds of Ver-nohia anthelmintica L played an important role in this treatment. Since it may activate tyrosinase and improve the melanin production, many chalcone compounds and derivatives were described as potential inhibitor on tyrosinase which may act as skin lightening and whitening agents. However, chalcones which showed activator effect were seldom reported. In order to search for chalcones with high activities on tyrosinase, eight novel chalcone derivatives containing benzothiazole and eight amide-derived chalcones were synthesized in this work. All the compounds were idenpngied by 1H NMR, 13C NMR, IR, HRMS and evaluated their activator effect on tyrosinase by measuring the oxidation rate of L-dopa. Compared with the reference drug 8-methoxypsoralen, compounds 4d, 4h, 5d, 7b and 7d showed some activator effect on tyrosinase. Amomg them, compound 7d demonstrated more potent activity with EC50=9.6 μmol/L than 8-methoxypsoralen, which EC50 value was 14.8 μmol/L. Further structural modification of this novel chalcones containing benzothiazole will be required for improving the solubility of them.

    Preparation and Thermal Kinetic Deactivation of Cross-linked Enzyme Aggregates of Penicillin Acylase
    MU Yangyang, ZHEN Qiannan, WANG Mengfan, QI Wei, SU Rongxin, HE Zhimin
    2014, 35(6):  1212-1218.  doi:10.7503/cjcu20131009
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    Cross-linked enzyme aggregates(CLEAs) is an efficient approach to obtain immobilized enzymes without the use of any pre-existing carriers. The preparation of CLEAs usually consisted of two simple steps: precipitation and cross-linking. In this work, CLEAs of penicillin acylase was preparaed using 50% ammo-nium sulphate solution as precipitant and 0.35% glutaraldehyde as cross-linking agent. The resulting CLEAs obtained an activity yield of 30.1% and higher optimal temperature(57 ℃) than free penicillin acylase(47 ℃) as well as an obvious shift of optimal pH from 8.3 to 10.0. Moreover, compared with free enzyme, the thermal stability of CLEAs was largely enhanced which facilitated the application of penicillin acylase in high-temperature reaction systems. Based on the thermal deactivation kinetics study, it was found that the deactivation model of penicillin acylase changed from one-step model to serial model through immobilizing as CLEAs. The higher deactivation energy of CLEAs(549.2 kJ/mol) than free enzyme(248.8 kJ/mol) also explained the excellent stability of CLEAs under high temperature environment. In addition, CLEAs exhibited favorable reusability after using 7 times.

    Study on Proton Transfer of 2-(2’-Hyhroxyphenyl)imidazo[1,2-a]pyridine with Cucurbit[7]uril by Spectroscopic Methodology
    YI Pinggui, LIU Jin, CHEN Jian, YU Xianyong, LI Xiaofang, ZHENG Baishu, TAO Hongwen, HAO Yanlei
    2014, 35(6):  1219-1223. 
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    Proton transfer exist in a large variety of chemical and biochemical processes as one of the basic reactions of chemical and biochemical systems. Studies on proton transfer of organic molecules in versatile macrocyclic is necessary, and it can provide some reference to the study of the proton transfer process in the biological system. In this work, the interaction of 2-(2'-hyhroxyphenyl)imidazo[1,2-a] pyridine(HPIP) with versatile macrocyclic, namely, cucurbit[7] uril(CB7) and the effect on the excited state intramolecular proton transfer(ESIPT) of HPIP have been investigated by photophysical methods. Fluorescence emission spectroscopy, transient fluorescence spectra and UV absorption spectroscopy studies illustrate significant interaction between HPIP and CB7. According to the transient fluorescence spectra, due to the formation of HPIP-CB7 complex, the lifetime of HPIP was decreased and the quantum yield was increased followed by the increase of the CB7 concentration. Fluorescence emission spectroscopy showed that the ESIPT of HPIP was increased in dioxane and decreased in n-hexane. Furthermore, the absorption data showed that the HPIP molecules and CB7 forming 1:1 complex both in dioxane and n-hexane, and these contentions have been verified by fluorescence emission data.

    Encapsulation of Cytarabine in Cucurbit[7]uril and Its Effects on Stability of the Drug
    HUANG Ying, SONG Guixian, TANG Qing, WANG Juan, TAO Zhu, XUE Saifeng, ZHANG Jianxin
    2014, 35(6):  1224-1228.  doi:10.7503/cjcu20130966
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    The interaction of cucurbit[7]uril(Q[7]) with cytarabine(Ara-C) in different proton forms were studied by ultraviolet absorption spectroscopy and 1H NMR technique in details. Complexation by Q[7] has also been investigated to cause pKa shifts and stability of drug. The results showed that Q[7] encapsulated the Ara-C and shifted its pKa value by down to 0.3 units. Ara-C in different proton forms with Q[7] informed 1∶1 inclusion complexes, and the formation constants were (9.48±0.29)×103 L/mol and (6.30±0.04)×103 L/mol for the Q[7]-Ara-C+ system and Q[7]-Ara-C system, respectively. Moreover, The formation of inclusion complexes between Q[7] with Ara-C was confirmed by 1H NMR, the pyrimidine moiety of Ara-C were entrapped in the cavity of the host and the D-ribose ring was likely located at the outside cucurbituril cavity. In addition, stability studies were investigated by initial uniform rate experiment. The results revealed that complexation of Ara-C with Q[7] offers a major improvement in drug stability.

    Effect of Peripheral Substituents on Luminescent Properties of the Porphyrin Platinum(Ⅱ) Complexes
    YUAN Wei, REN Qingjiang, SUN Hengda, LI Hui, CHENG Yanxiang, MA Dongge
    2014, 35(6):  1229-1235.  doi:10.7503/cjcu20130944
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    Porphyrin platinum(Ⅱ) complexes with efficient red phosphorescent emission have attracted extensive interest due to their potential application in the organic light emitting diodes(OLEDs). However, the strong π-π intermolecular interactions derived from their rigid planar coordination geometry result in the occurrence of self-quenching and affect their performance. In this work, a series of porphyrin platinum(Ⅱ) complexes with different peripheral substituents(PtTEMP, PtTBMP, PtOMPP and PtDMPP) were designed, synthesized and characterized, for the purpose of effectively restraining the intermolecular π-π interaction. Single crystal X-ray structure analysis indicated that they had ideal square-planar geometry around Pt atom, and bulky t-butyl substituent could inhibit effectively π-π interactions. The peripheral substituents hardly affected absorption and emission properties of the complexes, and the luminescent peaks at 646—656 nm were assigned to 3LC phosphorescent emission. PtTBMP showed the highest emission quantum yield(0.58) and external quantum efficiency(EQE, 6.3%) due to strong steric effect of t-butyl. The luminous efficiency of PtDMPP with three methoxyl substitutents was better than PtOMPP with two methoxyl, the corresponding emission quantum yield were 0.36 and 0.29, and were 2.4% and 1.7%, respectively. The results indicated that the encapsulating effect of the peripheral substituents could improve luminescent efficiency of porphyrin platinum(Ⅱ) complexes.

    Mild and Efficient Method for Synthesis of α-Halomethylketones
    LIU Kaijian
    2014, 35(6):  1236-1240.  doi:10.7503/cjcu20130799
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    α-Halomethylketones are building blocks for the synthesis of various compounds due to their selective transformations with different reagents. Moreover, a wide range of α-halomethylketone derivatives attract increasing interests in pharmaceutical chemistry. α-Halomethylketones are also widespread used as intermediates in organic synthesis, such as in Favorskii rearrangement and Reformatsky reaction. However, their direct synthesis from the corresponding methylktones by N-halosuccinimides, molecular halogen and metal halides has been plagued by poor regioselectivity and over-halogenation. For the above reasons, a simple, convenient and environmentally benign protocol to synthesize the α-halomethylketones was developed by catalytic hydration of haloalkynes, which can be easily prepared in one step from commercial terminal alkynes. In the presence of 3%(molar fraction) BrettPhosAuNTf2 and 3 mmol H2O in dichloroethane at room temperature, a broad range of haloalkynes were converted into α-halomethylketones in excellent yield through gold-catalyzed hydration reaction. The presented methodology will provide new strategies for α-halomethylketones-type drug design and synthesis, which has important academic significance and application value.

    Physical Chemistry
    Density Functional Theoritical Studies on Catalytic C-H Activation Reaction: Problem of Truncated Model
    ZHANG Lei, XU Zengping, YU Haoyu, FANG Decai
    2014, 35(6):  1241-1246.  doi:10.7503/cjcu20140246
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    Density functional theory method was employed to simulate a Rh(PPh3)3Cl catalyzed C-H activation/C-C cross-coupling reaction, in which three typical processes, namely, C-H activation, migratory insertion and reductive elimination, were characterized. The obtained results show that the rate-determining step is migratory insertion with the free-energy barrier of 108.3 kJ/mol. In order to test the validation of truncated models, two small catalysts Rh(PMe3)3Cl and Rh(PH3)3Cl were also used to study the same coupling reaction. Our calculations suggested that truncated models led to misunderstanding of reaction mechanism and free-energy changes, especially for migratory insertion process, since the steric effect and entropic contribution play a great role on these types of reactions.

    H2O2 Generated by Natural Biofilms Under Light Irradiation and Its Effects on Degradation of Sodium Dodecyl Benzene Sulfonate
    DONG Deming, LI Ming, SUN Jiaqian, ZHAO Tianyu, HUA Xiuyi, GUO Aitong, LIANG Dapeng
    2014, 35(6):  1247-1251.  doi:10.7503/cjcu20140194
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    In this study, generation of H2O2(hydrogen peroxide) by natural biofilms of different bioactivities under light irradiation was investigated, and effect of light on sodium dodecyl benzene sulfonate(SDBS) degradation in such natural biofilm-water systems was evaluated. The role of H2O2 in the degradation of SDBS was also verified by SDBS degradation experiments in H2O2 solution without biofilms. The results indicated that: (1) biofilms with full bio-activity can generate H2O2, while biofilms without any bio-activity or bio-activity of photosynthesis can not generate H2O2; (2) much more SDBS can be degraded under visible light than in darkness; (3) light and Fe2+ can promote the degradation of SDBS in the presence of H2O2. H2O2 produced by natural biofilms should be one of the most important causes of the degradation of SDBS, and the roles of H2O2 in the degradation should include both direct oxidation of SDBS by H2O2 and the indirect role in generating active oxygen species.

    Ni/SAPO-11 Promoted by Rare Earth Element Ce for Hydroisomerization of n-Heptane
    SUO Yanhua, LI Xiumin, CHEN Gang, CUI Yingxue, SUN Yujia, WANG Yingjun
    2014, 35(6):  1252-1257.  doi:10.7503/cjcu20140075
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    The monometallic catalyst Ni/SAPO-11 was prepared via the impregnation method. Then, the bimetallic catalyst Ni-Ce/SAPO-11 was prepared via the sequential impregnation method. The crystal structure and acidity of these two catalysts were determined by X-ray powder diffraction, Brunauer-Emmett-Teller(BET) methods and temperature-programmed desorption of ammonia. With addition of Ce, the BET surface areas and porous volume of Ni/SAPO-11 and total acidity were increased, and the acid strength was decreased. Introduction of Ce improved the dispersion of Ni on the surface of SAPO-11. Addition of Ce could improve the selectivity of the hydroisomerization of n-heptane considerably. Under the conditions of n(H2)/n(n-C7H16)=12, weight hourly space velocity=3.52 h-1, catalyst weight=0.3 g, and the reaction temperature of 300 ℃, the conversion of n-heptane could reach 25.4% and the isomerization selectivity to i-heptane could reach 90.4%.

    Pattern Formation Mechanism via Evaporation of Colloidal Droplet Containing PTFE Particles and NaCl
    ZHANG Yongjian, LIU Zhengtang, QIAN Yimeng, LI Zhiguang, ZANG Duyang
    2014, 35(6):  1258-1266.  doi:10.7503/cjcu20140073
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    The pattern formation via the evaporation of colloidal droplet containing polytetrafluoroethene(PTFE) particle and NaCl salt were investigated. Due to the pinning of the contact line caused by the PTFE particles, a notable “coffee ring” effect was observed in the drying of droplets containing only colloidal particles. Furthermore, because of the stress field built between the inner liquid zone and outside solid zone which is induced by the azimuthal component of the surface tension of the liquid zone, cracks start to emerge in the gel zone and propagate from the edge of the droplet to the centre. The quantity of the cracks decreases with increasing volume fraction of particles. With the presence of NaCl, the outward capillary flow was greatly restricted, leading to a more homogeneous deposition of the colloidal particles. Interestingly, a rough dendrite structure containing both salt and PTFE particles was formed. It was resulted from the release of stress induced by evaporation.

    Theoritical Studies on the Structure and Absorption Spectra of Neo-Confused Metal Porphyrin
    GONG Jian, CAO Hongyu, LI Shenmin, TANG Qian, YANG Yanjie, ZHENG Xuefang
    2014, 35(6):  1267-1276.  doi:10.7503/cjcu20140046
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    On the basis of detailed density functional theory(DFT), the molecular geometrical structures and orbital energy levels of free base porphyrin(FBP) and neo-confused porphyrin(NECP) coordinated with Mg, Ni, Cu, Zn were studied at B3LYP/6-31+G(d) level. The electronic absorption spectra of metal coordinated porphyrins were studied in gas phase at time dependent density functional level, including the excitation energy, absorption wavelength, oscillator strength and the orbital composition of the electronic transition. Since the metal coordinated FBPs(M-FBP) have D4h symmetry, HOMO/HOMO-1, LUMO/LUMO+1 degenerate respectively with the similar orbital energy level. The energy gaps of HOMO-LUMO of M-FBPs are about 3.0 eV. The structure and orbital properties of M-FBPs evolve strong Soret bands in the absorption spectra. Due to the change of C/N atom in the center structure of NECP, M-NECP molecular frontier orbitals composition is more complicated than that of M-FBP. In M-NECPs, the molecular orbital energy gaps(HOMO-LUMO) reduce to about 2.6 eV. The C/N exchange strategy can vary the molecular symmetry and molecular orbital composition of M-NECPs, which leads to the energy level splitting, strong electronic absorption peaks of Soret band and the appearance of Q absorption band. All the parameters of M-FBPs and M-NECPs were investigated in three different solvents(water, chloroform and benzene). Under the solvent conditions, the electronic absorption spectra of M-FBP and M-NECP take place red shift along with the weaken polarity of solvent(water, chloroform, benzene) and enhance the absorption peak intensity.

    One-step Preparation of H3PW12O40/Bi2WO6 Nano-photocatalysts by Microwave Liquid Process and Its Photocatalysis Denitrification Properties
    CHEN Ying, XING Chen, JI Shenglun, LIANG Hongbao, ZHANG Hongyu, CHEN Yan
    2014, 35(6):  1277-1285.  doi:10.7503/cjcu20140021
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    Immobilized nano-photocatalysts H3PW12O40/Bi2WO6 was prepared by microwave liquid one-step process. The morphology, structure and properties of the prepared catalysts were characterized and investigated by UV-Vis diffuse reflectance spectra, scanning electron microscopy(SEM), NH3 temperature programmed desorption(NH3-TPD), pyridine adsorption Fourier transform infrared spectroscopy(Py-FTIR) and X-ray diffraction(XRD), respectively. Their photocatalytic denitrification properties were evaluated by using the model oil with 15 mg/g pyridine. The results show that H3PW12O40/Bi2WO6 photocatalysts could be more efficiently synthesized by microwave liquid one-step process, and it could be excited by lower photon energy than that synthesized by common impregnation immobilization method. Immobilization of H3PW12O40 on Bi2WO6 could improve the acid content in Bi2WO6 nanoparticle surface, change the acid strength of Bi2WO6 precursor solution thereby controll the catalyst morphology. The influences of preparation conditions on photocatalytic properties of H3PW12O40/Bi2WO6 were investigated. It was found that H3PW12O40/Bi2WO6 nano-photocatalyst, with the H3PW12O40 loading(mass fraction) of 15%, prepared by microwave liquid one-step process under microwave power 800 W for 90 min possessed the best performance in the photocatalytic denitrification of model oil containing photocatalysts(mass ratio of catalyst to model oil was 1/300) after 500 W Xe lamp irradiation for 60 min, with the denitrification rate reached 92.63%.

    Sunlight-Responsive Ag2S/Ag3PO4 Composite Preparation and Degradation of Salicylic Acid
    ZHU Suiyi, XU Dongfang, FANG Shuai, GENG Zhi, YANG Xia
    2014, 35(6):  1286-1292.  doi:10.7503/cjcu20140003
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    An efficient sunlight responsive Ag2S/Ag3PO4 composite was prepared by co-precipitation method combined with hydrothermal treatment. The morphology, composition, surface physical and chemical property and optical absorption property were characterized by scanning electron microscope(SEM), X-ray powder diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and ultraviolet-visible diffuse reflection(UV-Vis DR). The 1%Ag2S/Ag3PO4 composite has rough surface with smaller particle size less than 0.8 μm and wider bandgap(2.24 eV) compared to Ag3PO4. The photocatalytic activity of Ag2S/Ag3PO4 was evaluated by degradation of salicylic acid which is a typical material in pharmaceuticals and personal care products(PPCPs) and harmful to human health and ecosystems. The results show that Ag2S/Ag3PO4 composite doped 1%Ag2S with hydrothermal treated at 120 ℃ for 4 h exhibits excellent salicylic acid degradation efficiency reached to 88.2% under simulated sunlight irradiation for 60 min and the light source current intensity is 15 A, when Ag2S/Ag3PO4 used 0.15 g, the initial concentration of salicylic acid is 10 mg/L and pH is 6.0, respectively. The contribution of various parameters for the enhanced photocatalytic activities is revealed in detail. The primary reasons for the increased simulated sunlight photocatalyst activity are contribution to the perfect cubic crystal structure, smaller particle size and broaden the visible spectral response. Doping sulfide is benefit to absorb sunlight and separate the electron-hole effectively.

    Preparation of PVP-based Iodine-iodide Gel-electrolyte and Its Application in DSSCs
    LU Shanfu, LIU Yiyang, XIANG Yan
    2014, 35(6):  1293-1299.  doi:10.7503/cjcu20131250
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    In the preparation of gel polymer electrolyte(GPE) for dye-sensitized solar cell(DSSCs), lithium iodide was used as the I- source, ethylene carbonate(EC) and propylene carbonate(PC) were used as the solvent, polyvinyl pyrrolidone(PVP) and polyvinylidene fluoride(PVDF) were used as the gelling agent. Raman spectroscopy, cyclic voltammetry and alternate current(AC) impedance were used to characterize the gel electrolyte. The results show that the concentration(mass fraction) of polymer and the ratios of PVP to PVDF and iodine to iodide have great influence on the performance of the GPE. The prepared GPE comes to the highest ion conductivity of 3.27 mS/cm at room temperature when the concentration of polymer is 10%[m(PVP)/m(PVDF)=80∶20] and the molar ratio of LiI/I2 is 30∶1 with the concentration of iodide as 0.042 mol/L. DSSC with the PVP-based GPE achieves a good output performance with open circuit voltage of 0.64 V, short circuit current density of 13.6 mA/cm2, fill factor of 0.595, the overall photoelectric conversion efficiency of 5.18% under 100 mW/cm2 of simulated sunlight and exhibits a good stability during the test time of 30 d. The new GPE which is cheap and available overcomes the problem of liquid electrolytes leakage in DSSCs.

    Mechanistic Studies on CH3CH2O+HCHO Reaction and Rate Constants of Major Channel
    GUO Sha, WANG Weina, JIN Lingxia, WANG Shuai, WANG Wenliang
    2014, 35(6):  1300-1306.  doi:10.7503/cjcu20131237
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    The mechanism of the reaction between CH3CH2O and HCHO was investigated at CCSD(T)cc-pVDZ//B3LYP/6-311++G(d,p) level. Eight possible reaction channels(five H-abstraction channels and three H-isomerization channels) for the title reaction were idenpngied. The results indicated that channel R→IMa(CH3CH2O…CH2O)→TS1→IM1b→P1(CH3CH2OH+CHO) was the most favorable channel with the apparent activation energy of 14.65 kJ/mol. The rate constants of the path R1 were evaluated over a temperature range of 275—1000 K via the canonical variational transition state theory(CVT) combined with a small-curvature tunneling correction. The fitted three-parameter expression for the path R1 is kCVT/SCT=2.26×10-17T0.57exp(-1004/T) and R1 has a positive temperature effect over a temperature range of 275—1000 K.

    Mesoporous Titania Supported Copper Hydroxide as an Efficient Heterogeneous Catalyst in Oxidative Homocoupling of Alkynes
    ZHANG Haipeng, PAN Qingzhi, ZOU Yongcun
    2014, 35(6):  1307-1310. 
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    Ordered mesoporous titania supported copper hydroxide was used as catalysts in heterogeneous oxidative homocoupling of alkynes(Glaser reaction). The results showed high catalytic performance. Highly dispersed copper hydroxide was regarded as the active site and mesoporous structure of TiO2 benefit the high dispersion of active sites as well as the diffusion of the reactants and products in the reactions. 1,3-Dyne derivative, the products of Glaser reaction, is an important class of compounds in chemistry and materials science. Thus, Cu(OH)2/TiO2 is of great importance in the industrial application.

    Idenpngication of Functional Residues in Maltose Transporter with the Elastic Network Model
    ZHOU Xiaofeng, XIE Xiaolu, ZHANG Lei, LI Chunhua, LOU Jiaoying, LIU Naibo, DING Zhenshan
    2014, 35(6):  1311-1317.  doi:10.7503/cjcu20131185
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    Maltose transporter is an important kind of transmembrane transporters with significant biological functions which bears the transportation of intracellular and extracellular maltose molecules. The transport process of maltose molecule accompanies with large scale cooperative motions between different domains of maltose transporter. And these motions involve some key residues that mediate signal transduction and allosteric effects between different regions of the protein. In this study, we idenpngied the key residues in this protein system with the thermodynamic method based on the elastic network model which was developed by our group. On this basis, we explored the long-range synergies within the maltose transporter. These results are helpful to a better understanding the molecular mechanisms of function of transporters.

    Synthesis of Mesoporous Carbon/Iron Carbide Material and Its Hydrogen Storage Capacity
    ZHANG Lingna, TAO Jinhui, JI Kaiji, YUE Qunfeng
    2014, 35(6):  1318-1322.  doi:10.7503/cjcu20131101
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    Using 1-cyanomethyl-3-methylimidazolium tetrachloridoferrate(Ⅲ) as precursor and SBA-15 as template, the mesoporous iron carbide frameworks were synthesized by the hard template method, and the structure and morphology were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and N2 adsorption-desorption isotherms. The influences of the synthesis temperature and calcination time on the material surface area were also investigated. The results showed that mesoporous carbide with large specific surface area was obtained under 800 ℃. Moreover, uniform pore size distribution and complete structure and specific surface(517.96 m2/g) could be built with prolonging calcination time. Furthermore, hydrogen adsorption isotherm revealed that the material exhibited medium hydrogen storage capacity.

    Polymer Chemistry
    Preparation, Characterization and Application of Amine-functionalized Poly(lactic acid) Electrospun Fibers
    XIONG Xi, LI Qiang, ZHANG Xucheng, YU Jian, GUO Zhaoxia
    2014, 35(6):  1323-1329.  doi:10.7503/cjcu20140219
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    Amine-functionalized poly(lactic acid)(PLA) nanofibers were prepared by co-electrospinning of PLA and aminopropyltriethoxysilane(KH550) in 1,1,1,3,3,3-hexafluoroisopropanol. The contents of amine groups on the surfaces of the fibers were measured by chemical titration. The results show 19%—26% of total amine groups appeared on the fiber surfaces when 3%—13% of KH550 to PLA is added. The amine-functionalized PLA nanofibers were also characterized by field emission scanning electron microscopy, differential scanning calorimetry(DSC), contact angle measurements and uniaxial tensile tests. It has been shown that the addition of KH550 can introduce amine groups on PLA fiber surfaces, meantime the fiber diameter decreases, Tg of PLA increases, Tm of PLA decreases, the hydrophilicity of the fiber mat slightly increases and its mechanical properties decreases. Au nanoparticles were adsorbed on the surface of amine-functionalized PLA nanofibers, which showed good catalytic activity and reusability for the reduction of 4-nitrophenol.

    Surface and Interfacial Properties of Polyoxyethylene Ether-type Surfactants
    HUANG Hailong, LI Hongyu, ZHANG Lei, REN Tianrui
    2014, 35(6):  1330-1335.  doi:10.7503/cjcu20140113
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    A series of poly nonylphenol polyoxyethylene ether nonionic surfactants with different polymerization degerees was synthesized with nonyl phenol and formaldehyde. The structures were characterized by infrared spectroscopy and nuclear magnetic resonance. Moreover, the surface properties were evaluated using the surface tension method. It is found that critical micelle concentration(cmc) of monomer, dimer and trimer incease with increasing of the number of hydrophilic group epoxyethane(EO) of the surfactants. In the case of the same number of EO, the cmc of surfactants were significantly reduce with the increase of the degree of polymerization. Although dimer and trimer show good surface properties, the surface property of trimer is more excellent than dimer. Moreover, dimer and trimer show more excellent adsorption and dispersion performance because the arrangments of them on the air/water boundary are significantly more compacted than dimer.

    Synthesis,Characterization of Bis(arylcarboximidoylchloride)pyridine Ni(Ⅱ) Complexes and Their Catalytic Behavior for the Synthesis of Liquid Polybutadiene
    LIU Heng, LIU Li, WANG Feng, JIA Xiangyu, BAI Chenxi, ZHANG Chunyu, ZHANG Xuequan
    2014, 35(6):  1336-1342.  doi:10.7503/cjcu20131246
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    A series of bis(arylcarboximidoylchloride)pyridine Ni(Ⅱ) complexes with the general formula [2,6-(ArN═CCl)2C5H3N]NiX2[Ar=2,6-Me2C6H3, X=Br(1a) or Cl(2a); Ar=2,4,6-Me3C6H2, X=Br(1b) or Cl(2b); Ar=4-Cl-2,6-Me2C6H2, X=Br(1c) or Cl(2c)] were synthesized and characterized by FTIR and elemental analysis. The molecular structures of 1a—1c were further characterized by X-ray single crystal diffraction, and the geometry at the metal centre for all the three complexes can be best described as distorted trigonal bipyramidal. At the presence of ethylaluminum sesquichloride(EASC), all the Ni(Ⅱ)-based complexes performed high activities towards butadiene polymerization at 20 ℃, liquid polybutadienes(PB) with molecular weight of 4700—5200 and medium cis-1,4-PB content(74.8%—77.2%) was obtained. Catalytic activities of the catalysts and the microstructures of the resulting polymers were little depen-dent on the ligand environment and highly dependent on polymerization conditions.

    Effect of Side Chain Structure on Properties of Side Chain-style Sulfonated Poly(arylene ether)
    ZHANG Zhenpeng, WANG Yan, ZHANG Jingjing, ZHANG Xiaofei, PANG Jinhui, JIANG Zhenhua
    2014, 35(6):  1343-1347.  doi:10.7503/cjcu20131222
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    Three kinds of sulfonated poly(arylene ether)(SPAE) with the same backbone and different side chains were prepared from the new difluoride monomer and other commercial monomers by nucleophilic substitution reaction. The relationship between structures and properties of these polymers were investigated. As a result, sulfonated polymers with flexibility aliphatic side chains exhibited high proton conductivity and low swelling ratio than that with aromatic ones at the same IEC level. Because the sulfonic acid groups located at the end of aliphatic side chain have better motility than located aromatic ones, which helps for aggregation of sulfonic acid and forming ionic clusters in the membranes. The microphase-separation morphology of the three polymers were analized by SAXS, The results indicate that polymers with more flexible side chains(SPAE-Ⅲ) have large phase separation size. Combined proton conductivity and water swelling data, SPAE-Ⅲ membranes are the most suitable one for proton exchange membrane application.

    Synthesis and Solution Properties of CS-g-PLGA Graft Polyampholytes
    WEI Zhaojun, CHEN Ye, WANG Dongmei, FANG Wenxiang, CHEN Tao, ZHANG Suning
    2014, 35(6):  1348-1354.  doi:10.7503/cjcu20131095
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    The graft polyampholytes containing a chitosan backbone and poly(L-glutamic acid) branches, i.e. CS-g-PLGA(CGA), with different compositions were synthesized. The molecular architecture and the composition of CGA were characterized. The influences of environmental conditions, such as pH value, ionic strength and ionic types, on the aqueous solution properties of CGAs were investigated. The results show that the isoelectric point(IEP) of CGA shifts to higher pH values with increasing the ionic strength. The larger the ion hydration radius is, the less it influences the IEP. The CGA with approximative amino and carboxyl contents is more sensitive to the variation of ionic strength. Moreover, CGAs exhibit notable pH responsibility to form reversible aggregates in acidic and alkaline solutions, respectively. The stability of the aggregates is found to be improved by increasing the length of PLGA branches for CGAs with similar amino content. The hydrodynamic radii of the aggregates depend on the charge density on CS backbone in acidic solutions and increase with increasing PLGA length in alkaline solutions.

    Synthesis and Characterization of Conjugated Polymers Containing Bifluorenylidenes Units
    TAN Shuzhen, MA Haixia, LIU Wei, ZHAO Hongchi, WU Yonggang, BA Xinwu
    2014, 35(6):  1355-1362.  doi:10.7503/cjcu20130969
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    A series of novel conjugated polymers containing bifluorenylidenes units was synthesized under mild conditions with W(CO)6 as the catalyst, and the repeated units of the polymers were linked at 9 position of fluorine by the double bond. The new polymers represent narrow band gap, and the maxium absorption of polymer P1 in film is peaked at 710 nm. In most cases, the conjugated polymers containing fluorenes units show strong photoluminescence(PL) emission, while the synthesized polymers show no photoluminescence(PL) emission. The synthesized polymers contain new backbone structure. Their optical and electrochemical properties were studied in detail.