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Chinese Journal of Polymer Science 2001年第3期19卷 297-301页

作者： Zi-chen Li Yue Shen Yu-zeng Liang Fu-mian Li Department of Polymer Science & engineering college of chemistry Peking University Beijing 100871, China Beijing Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The morphological transition of molecular assemblies in aqueous solutions for a new amphiphilic diblock copolymer induced by changing the initial solvent conditions was studied by transmission electron microscopy (TEM). The copolymer was polystyrene(77)-b-poly[2-(beta -D-glucopyranosyloxy)ethyl acrylate (6)] (PSt(77)-b-PGEA(6)) and the solvent was a mixture of DMF and THF. PSt(77)-b-PGEA(6) yields vesicles and tubules when it is initially dissolved in THF and DMF respectively. The morphological transition between vesicles and tubules can be achieved by simply varying the amounts of THF and DMF, or changing the temperature at which the aggregates were prepared.

关键词： block copolymer amphiphile glycopolymer self-assembly tubule vesicle

Prediction of Water Activities in Multicomponent Solutions of Metal Chlorides from the Thermodynamic Properties of Corresponding Binary Systems

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Journal of Central South University 2000年第1期12卷 29-33页

作者： LI Yuan gao,ZHANG Quan ru,FANG Zheng(college of chemistry and Chemical engineering, Central South University of Technology, Changsha 410083, China) 1. college of chemistry and Chemical engineering Central South University of Technology 410083 Changsha China

In order to calculate the activity coefficients of water in aqueous solution of metal electrolytes, a simplified model predicting them in ternary or multicomponent solutions with common anions from the activity data of water of the corresponding binary systems has been developed based on an assumption that the electrolytes in the solution are treated as independent particles instead of their ion forms, and the interaction of the salt( i ) salt( j ) pair in the solution is assumed to be much weaker than that of water salt pair due to the common anions of both of salts. The model was applied to the systems such as KCl H 2O NaCl, MCl H 2O M′Cl 2 (M represents Na and K, M′ represents Ca and Ba) and KCl H 2O NaCl BaCl 2 with satisfying results. The interchange energies of the studied component pairs between water and salts have also been determined by the corresponding binary aqueous solutions.

关键词： activity of water electrolyte thermodynamic model interchange energy

A new way to synthesize benzoin isopropyl ether on Cu-Fe-hydrotalcite

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Journal of Natural Gas chemistry 2010年第1期19卷 77-80页

作者： Xianmei Xie, Xia An, Kai Yan, Xu Wu, Jianling Song, Zhizhong Wang college of chemistry and Chemical engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China [a] college of chemistry and Chemical engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

An efficient synthesis of benzoin isopropyl ether with benzaldehyde and propanol in the presence of heterogeneous recyclable Cu-Fe-hydrotalcite catalyst has been explored. Cu-Fe-hydrotalcite was firstly successfully synthesized over Jahn-Teller effect of Cu^2＋. The catalytic test result showed that Cu-Fe-hydrotalcite could be used as a good catalyst in the synthesis of benzoin isopropyl ether. The highest conversion of ben- zaldehyde was 59.7% and the selectivity of benzoin isopropyl ether was nearly 100%. By this new method, not only was the cyanide poisoning avoided, but also the synthesis of benzoin isopropyl ether could be completed in one step instead of traditional two steps with both condensation and etherification.

关键词： benzoin isopropyl ether benzaldehyde propanol Cu-Fe-hydrotalcite

Fluorometric enzyme immunosensing system based on natural product resveratrol for horseradish peroxidase and Ag/SiO_2 nanoparticles

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Science China chemistry 2008年第3期51卷 233-240页

作者： GONG FuChun, CAO Zhong, TAN ShuZhen, TAN YaFei & HE XiaoChun college of chemistry and Environmental engineering, Changsha University of Science and Technology, Changsha 410076, China 1. college of chemistry and Environmental engineering Changsha University of Science and Technology Changsha 410076 China

The properties of resveratrol (3′, 4′, 5-trihydroxystlbene, RST) were for the first time evaluated as a potential substrate for horseradish peroxidase (HRP)-catalyzed fluorogenic reaction. The properties of RST for use as fluorogenic substrates for HRP and its application in immunoassays were compared with commercially available substrates such as p-hydroxyphenylpropionic acid (pHPPA), chavicol and Amplex red by a fluoroimmunosensing method in the use of Schistosomia japonicum antibody (SjAb) as a model analyte. The fluoroimmunosensing device was constructed by dispersing Schistosomia japonicum antigen (SjAg), nano-Ag/SiO2 particles and sol-gel at low temperature. In pH 5.8 Britton-Robinson buffer (B-R), HRP-SjAb conjugates can catalyze the polymerization reaction of RST by H2O2 forming fluorescent dimmers. The increase of the fluorescence intensity of the dimmers product at emission of 462 nm (excitation: 315 nm) is proportional to the concentration of HRP-SjAb binding to the SjAg entrapped in the nano-Ag/SiO2 particles-sol-gel matrix. A competitive binding assay has been used to determine SjAb in rabbit serum with the aid of SjAb labeled with HRP. Substrate RST showed comparable ability for HRP detection and its enzyme-linked immunosensing reaction system, in a linear detection ranging of 1.5×10-6-7.3×10-4 g/L and with a detection limit of 1.5×10-6 g/L. The immobilized biocomposites surface could be regenerated by simply polishing with an alumina paper, with an excellent reproducibility (RSD = 4.7%). The proposed method has been successfully used for analysis of the rabbit serum sample with satisfactory results.

关键词： resveratrol HRP fluorogenic substrate Ag/SiO2 nanoparticles enzyme-linked immunosensing Schistosomia japonicum

SYNTHESIS AND PROPERTIES OF A NEW AZOBENZENE SIDE-CHAIN POLYMER CONTAINING A TEMPO RADICAL

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Chinese Journal of Polymer Science 2002年第4期20卷 285-290页

作者： Yong Zhang Ze-da Xu Xing-he Fan Xiao-fang Chen Xin-hua Wan Qi-feng Zhou Department of Polymer Science and engineering college of chemistry and Molecular engineering Peking University, Beijing 100871, China Peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

To allow anisotropies of optical properties in a magnetic field, nitroxide radical is introduced into the ortho-position of the phenylene ring in the side chain. A new azobenzene side-chain polymer (TEMPO-PAZ) containing TEMPO radical was synthesized. The polymer has a good solubility in organic solvents. The ESR spectrum of the polymer indicated three absorption lines characteristic of TEMPO radical. The optical phase conjugated responses (I-4) of the polymer films were investigated by degenerate four-wave mixing (DFWM). The experimental results showed that optical phase conjugated response of the TEMPO-PAZ could be easily controlled by choosing the appropriate direction of magnetic field presumably due to the nitroxide radical in the TEMPO-PAZ molecular structure. For the polymer investigated here, the nitroxide radical was introduced to increase optical phase conjugated response intensity in a magnetic field, aiming originally at searching for a new photo-active organic magnetic multifunctional materials.

关键词： azobenzene nitroxide radical polymer photo-active organic magnetic materials optical phase conjugated responses

Nano Au/TiO_2 hollow microsphere membranes for the improved sensitivity of detecting specific DNA sequences related to transgenes in transgenic plants

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Science China chemistry 2008年第11期51卷 1066-1073页

作者： ZHANG YongChun, YANG Tao, ZHOU Na, ZHANG Wei & JIAO Kui college of chemistry and Molecular engineering, Qingdao University of Science and Technology, Qingdao 266042, China 1. college of chemistry and Molecular engineering Qingdao University of Science and Technology Qingdao 266042 China

Gold nanoparticles (nano Au)/titanium dioxide (TiO2) hollow microsphere membranes were prepared on the carbon paste electrode (CPE) for enhancing the sensitivity of DNA hybridization detection. The immobilization of nano Au and TiO2 microsphere was investigated with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The hybridization events were monitored with EIS us-ing [Fe(CN)6]3-/4- as indicator. The sequence-specific DNA of the 35S promoter from cauliflower mosaic virus (CaMV35S) gene was detected with this DNA electrochemical sensor. The dynamic detection range was from 1.0×10-12 to 1.0×10-8 mol/L DNA and a detection limit of 2.3×10-13 mol/L could be ob-tained. The polymerase chain reaction (PCR) amplification of the terminator of nopaline synthase (NOS) gene from the real sample of a kind of transgenic soybean was also satisfactorily detected.

关键词： Au nanoparticle TiO_2 hollow microsphere DNA electrochemical biosensor CaMV35S gene NOS gene

Synthesis and Crystal Structure of Bis(nitrate)- bis(N,N'-dimethyl-N,N'-dibenzenyl-urea)uranyl(Ⅱ)

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Chinese Journal of Structural chemistry 2003年第5期22卷 521-524页

作者： ZHU Li-Ming LI Bao-Long② CAO Zheng-Bai ZHANG Yong (college of chemistry and Chemical engineering, Suzhou University, Suzhou 215006, China) college of chemistry and Chemical engineering Suzhou University Suzhou 215006

The new uranyl complex UO2(NO3)2[PhN(CH3)C(O)(CH3)NPh]2 was synthesized and its crystal structure has been determined by single-crystal X-ray diffraction. Crystal data: C30H32N6O10U, triclinic, space group P with a = 7.772(1), b = 9.267(1), c = 12.644(1) ? a = 68.246(8), b = 73.871(9), g = 84.99(1)o, V = 812.4(2) ?, Mr = 874.65, Z = 1, Dc = 1.788 g/cm3, F(000) = 426, m = 5.062 mm-1, the final R = 0.022 and wR = 0.059 for 3571 observed reflections (I > 2s(I)). The central uranyl ion is coordinated by six oxygen atoms, two from the carbonyl groups of N,N-dimethyl-N,N-dibenzenyl-urea molecules and the other four from two nitrate groups.

关键词： substituted urea uranyl complex synthesis crystal structure

Structure of the Manganese (V) Complex-Mn·3/2(μ-DHBQ)·4H_2O·2Cl

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Chinese Chemical Letters 2000年第7期11卷 645-648页

作者： Yi Xiang CHENG Mao Lin HU Ji Xin YUAN Yun Chu WANG(Department of chemistry & Chemical engineering, Southeast University, Nanjing 210096 Department of chemistry, Wenzhou Teachers college, Wenzhou 325003) Dept. of Chem. and Chem. engineering Southeast University Nanjing 210096 China Department of chemistry Wenzhou Teachers College Wenzhou 325003 China

The novel complex of Mn(V): Mn·3/2(μ -DHBQ)·4H2O·2Cl (where, H2DHBQ =2,5-dihydroxyl- 1,4-benzoquinone) was synthesized and its crystal structure has been determined by X-ray diffraction. The complex belongs to trigonal system with space group P3(# 147), a= 1 .415(2)nm, c=0.6552(4) nm, V=1 .1371(7) nm-3, Z=2, Dx=1.183 g/cm3, μ=7.37 cm-1, F(000)=408.00,R=0.041, Rw=0.046.

关键词： Manganese (V) crystal structure bridging ligand 2,5-dihydroxyl-1,4-benzoquinone

The Total Synthesis of (±)-Hinesol and (±)-Agarospirol

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Chinese Chemical Letters 1997年第11期8卷 957-960页

作者： Jin Jun WANG Chang Jin YUE Jun QIU (Department Of Fine chemistry, Jilin Chemical engineering college, Jilin, 132002)Cang Yi QIAN(Department of chemistry, Qing Hua University, Beijing, 100084) Department of Fine chemistry Jilin Chemical Engineering College Jilin 132002 China Department of chemistry Qing Hua University Beijing 100084 China

A mild base-catalyzed retro-benzilic acid rearrangement of a proto-[2+2]photocycloadduct, formed in highly steroselective photoaddition of methyl 2,4-dioxo-pentanoate to 1,5-dimethyl-6-methylenecyclohexene, afforded a spiro[4, 5] decenedione from which hinesol and agarospirol were synthesized by means of reductive elimination of α-diketone and C1-homologation.

关键词： The Total Synthesis of Hinesol and Agarospirol

Synthesis of p-nitrophenol under normal pressure with A-1 phase transfer catalysis

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Journal of Central South University of Technology 2001年第1期8卷 54-56页

作者： ZHONG Shi an, OUYANG Xi, ZHOU Chun shan, CHENG Ben cheng (college of chemistry and Chemical engineering, Central South University, Changsha 410083, China) 1. college of chemistry and Chemical engineering Central South University 410083 Changsha China

p nitrophenol is synthesized using p nitrochlorobenzene and sodium hydroxide with phase transfer catalyst. Several reaction factors, such as catalyst type, the amounts of catalysts and sodium hydroxide, the concentration of sodium hydroxide solution as well as reaction time, affect greatly the yield of p nitrophenol. The optimum reaction conditions are as follows: A 1 used as phase transfer catalyst whose consumption is 6% (mole fraction) of p nitrochlorobenzene; the molar ratio of sodium hydroxide to p nitrochlorobenzene is 3:1; the concentration of sodium hydroxide solution is 50% (mass fraction). Nitrobenzene, whose molar amount is 2.45 times as much as that of p nitrochlorobenzene; reaction time is 7 h at 140 ℃ under normal pressure. The final yield of p nitrophenol is 83.6%.

关键词： phase transfer catalysis p nitrophenol synthesis