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Synthesis and Photocatalytic Property of the ZrO_2.TiO_2.Pillared Laponite

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Journal of wuhan university of Technology(Materials Science) 2011年第5期26卷 852-856页

作者：林英光 college of Materials Science and Engineering South China University of Technology

The ZrO2.TiO2.pillared laponite （Ti-Zr-lap） photocatalysts were prepared with intercalation reaction by supercritical fluid drying （SCFD）,and characterized by XRD,TEM,SEM and BET surface area analysis,and the photocatalytic properties of Ti-Zr-lap were investigated by degradation of azo dye acid red B （ARB）.The results showed that the ZrO2.TiO2.pillared structures in laponite could be formed,with the mass fraction of （Zr4＋＋Ti4＋）/laponite （Xm） increasing,the basal spacing and the BET surface area of Ti-Zr-lap significantly *** Ti-Zr-lap used as photocatalyst had the advantages of stable and porous layered structure,large surface area with the anatase type *** with the Ti-Zr-lap dried by air drying,the Ti-Zr-lap dried by SCFD showed better photocatalytic property which was very close to that of P2. *** the Ti-Zr-lap as photocatalyst with the optimum Xm of 0.16 and the calcination temperature of 500 ℃,under the conditions of the initial concentration of ARB 2. mg/L,photocatalyst concentration of 1.5 g/L and irradiation time 60 min,the decoloring rate of ARB could achieve 98.3%,indicating that the Ti-Zr-lap had excellent photocatalytic property.

关键词： ZrO2.TiO2.pillared laponite photocatalytic property intercalation reaction supercritical fluid drying

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

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Journal of central south {2. 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, {2. 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

DFT evaluation of the electronic structures and spectroscopic properties of the self-assembled [Pt_2._4(C≡CH)_8](M=Cu,Ag) clusters

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Science china chemistry 2009年第11期52卷 1954-1960页

作者： BAI FuQuan1,XIA BaoHui1,2.ZHANG HongXing1,YANG BaoZhu1,WANG Jian1 & SUN Lei1 1 State Key Laboratory of Theoretical and Computational chemistry,Institute of Theoretical chemistry,Jilin {2.,Changchun 13002.,china 2.college of chemistry,Jilin {2.,Changchun 13002.,china State Key Laboratory of Theoretical and Computational chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China college of chemistry Jilin University Changchun 130023 China

Electronic structures and spectroscopic properties of self-assembled [Pt2.4(C≡CH)8](M=Cu,Ag) clusters have been studied by the TD-DFT(time-dependent density functional theory) calculations with the polarizable continuum model(PCM).The ground-and excited-state structures were optimized by the DFT(density functional theory) *** calculated structures and spectroscopic properties are in agreement with the corresponding experimental *** [Pt2.g4(C≡CH)8] clusters have two stable ground state geometries(D4 and D4h symmetry).The calculated Pt-M distances suggest only very weak *** Cu-Cu distances are larger than the van der Waals radii of two Cu atoms and the Ag-Ag distances are analogous with the sum of van der Waals radii of two Ag *** excitation,the interaction of Pt…M,Ag…Ag is strengthened,while the Cu…Cu distances are shortened but they are still larger than the sum of van der Waals radii of two Cu *** lowest-energy absorptions are at 450,365 and 375 nm and the emissions are at 611,431 and 435 nm for [Pt2.u4(C≡CH)8],[Pt2.g4(C≡CH)8](A) and(B),*** transitions are all perturbed by the Cu or Ag composition through the UV-Vis spectra region;therefore,there are not pure ILCT or MPtLCT characteristics(ILCT:intraligand charge transfer;MLCT:metal-to-ligand charge transfer) in absorptions of heteropolynuclear [Pt2.4(C≡CH)8] *** the emissions and the lowest-absorptions have different transition characteristics for each complex,the emissions should not come from the lowest-energy *** the M…M interactions in the excited state of [Pt2.g4(C≡CH)8] are augmented,the emissions of [Pt2.g4(C≡CH)8] clusters bear prominent ILCT character,which is the reason why the emission wavelengths of [Pt2.g4(C≡CH)8] have a small hypsochromic shift relative to the emission wavelength of homoleptic [Pt(C≡CH)4]2.precursor.

关键词： electronic structures luminescence behavior heteropolynuclear complexes TDDFT

Non-invasive scanning ion-selective electrode technique and its applications to the research of higher plants

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Progress in Natural Science:Materials International 2007年第6期17卷 625-629页

作者： Sun Tong1, Xu Yue2. Li Peng1, Yu Shangguan2.and Yin Liping1(1. college of life Science, Capital Normal {2., Beijing 100037, china 2. Younger USA Science & Technology Corporation, 7 Dayton Lane, Amherst MA 01002. USA) [a]college of life Science Capital Normal University Beijing China [b]Younger USA Science & Technology Corporation Amherst MA USA

The process of various ions and molecules getting into and out of cells is critical for plant survival. The non-invasive scanning ion-selective electrode technique (SIET) is a non-invasive method to obtain the information of ions/molecules across membranes in plant. This technique can measure the absolute concentration of ions and molecules, and also their fluxes and directions of movement. The samples to be analyzed can be a single cell, a piece of tissue, a whole organ and even an intact seedling. This article reviews the recent progress made in plant physiology by using this technique and discusses its potentials in future studies on plant physiology.

关键词： non-invasive electrophysiology technique ion-selective electrode ion transport across membrane SIET.

Identification and Characterization of GH Receptor and Serum GH-binding Protein in Chinese Sturgeon (Acipenser sinensis)

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 811-816页

作者： Zhi-Yong LIAO1,2.and Shang-Quan ZHU2. 1college of life Sciences, Jiangxi Normal {2., Nanchang 33002., china 2.ey Laboratory of Proteomics Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai 2.0031, china college of life Sciences Jiangxi Normal UniversityNanchang 330027 China Key Laboratory of Proteomics Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China

Chinese sturgeon, a kind of cartilage ganoid, has a history of over one billion years and it is called the living fossil of aquatic biology since it keeps some evolutionary trace. Here, we characterized the growth hormone receptor (GHR) and serum growth hormone binding protein (GHBP) of Chinese sturgeon. It was shown that GHR was expressed in various tissues, mainly in hepatic, kidney and intestine tissues. GHR on the hepatic membrane has high and specific affinity for bream GH (brGH) and Scatchard analysis of the binding data showed a single class of high affinity binding site with an association constant Ka of 3.1×109 M–1. A specific band around 94 kD was detected by SDS-PAGE in cross-linking studies of membrane receptors. After incubation of Chinese sturgeon serum with 12.I-brGH, a 12.I-brGH-GHBP complex was identified by Sephadex G-75, indicating that in the serum exists GHBP specially binding to brGH.

关键词： Chinese sturgeon growth hormone receptor growth hormone binding protein ligand binding

Study on interaction between macrocell and microcell in the early corrosion process of reinforcing steel in concrete

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Science china(Technological Sciences) 2010年第5期53卷 1285-1289页

作者： LI LanQiang1,DONG ShiGang1,WANG Wei2.HU RongGang1,DU RongGui1,LIN ChangJian1,ZHUO XiangDong1 & WANG Jia2.1 State Key Laboratory of Physical chemistry of Solid Surfaces,Department of chemistry,{2. of chemistry and Chemical Engineering,Xiamen university,Xiamen 361005,china 2.{2. of chemistry and Chemical Engineering,Ocean university of china,Qingdao 2.6100,china 1. State Key Laboratory of Physical chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

An array electrode technique was developed as a novel electrochemical method for studying the interaction between macrocell and microcell in the early corrosion process of reinforcing steel in cement *** corrosion potential and galvanic current of macrocell corrosion of the reinforcing steel in cement mortar were imaged by the array electrode technique during the corrosion initiation and *** was certified that the corrosion macrocell current is closely related with the difference of corrosion potential between the anodic and cathodic *** corrosion macrocell and microcell always exist during the corrosion *** interaction of corrosion macrocell and corrosion microcell of steel in concrete was directly sensed by the array electrode for the first time,and was discussed in terms of corrosion electrochemistry.

关键词： reinforcing steel in concrete array electrode macrocell microcell

Cycloaddition mechanism for the resin-OsO_4-catalyzed of styrene: A DFT study

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Science china chemistry 2008年第1期51卷 19-24页

作者： ZHANG XingHui1, WANG KeTai1 & FANG Ran2.1 college of Chemical Engineering, Gansu Unite university, Lanzhou 730000,{2. 2.college of chemistry and Chemical Engineering, Sun Yat-sen university, Guangzhou 5102.5,{2. college of Chemical Engineering Gansu Unite UniversityLanzhou 730000China college of chemistry and Chemical Engineering Sun Yat-sen UniversityGuangzhou 510275China

The postulated intermediates in the base-free and base-assisted addition of OsO4 to styrene have been investigated at the B3LYP/6-311G** level of the theory. N(CH3)2.Ph) was chosen as the base of the resin-OsO4. According to our model calculations the [2.3] addition was found to be favorable with an activation of 2.2. cycloaddition remain high (>155.00 kJ/mol). In addition, the electronic structure analysis of the molecules was carried out by na- ture bond orbital (NBO). The computational results were in reasonable agreement with experimental results.

关键词： cycloaddition resin-OsO4 density functional theory

Preparation and characterization of some surface negatively charged residue mutants of cytochrome b_5

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Chinese Science Bulletin 2001年第7期46卷 555-559页

作者： WANG Yunhua, WANG Wenhu, LU Junxia, REN Yi, GU Shaohua, XIE Yi & HUANG Zhongxian1. Chemical Biology Lab, Department of chemistry, Fudan university, Shanghai 2.0433,{2. 2. Genetic Institute, School of life, Fudan university, Shanghai 2.0433,{2. Chemical Biology Lab Department of Chemistry Fudan University Shanghai China Genetic Institute School of Life Fudan University Shanghai China

Site-directed mutagenesis was used to obtain seven variants of tryptic fragment of bovine liver cytochrome bs (cyt bs), in which the negatively charged residues around the heme exposed edge of cyt bs were replaced by hydropho-bic amino acid alanine. Double-site mutants, triple-site mutants and even quadruple-site mutants were obtained. DNA sequencing and molecular weight measurements of the mutant proteins both confirmed that these site-directed muta-genesises were successfully performed. Spectroelectrochem-istry of these mutant proteins revealed that the apparent redox potentials of these mutant proteins caused a positive shift of 2.10 mV. The global structure of these mutant proteins did not show much difference from that of the wild type cyt bs, providing a solid base for the further study on the roles of the proteins’ surface charges.

关键词： cytochrome bs site-directed mutagenesis negative charge on the protein surface redox potential.

Synthesis,characterization,structures and magnetic property of chiral oxalate-bridged dicopper(Ⅱ) complexes

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Science china chemistry 2010年第6期53卷 1255-1260页

作者： WU Ling1,WANG Jun2.ZHU CaiFei1,LIN YiJi1,CHEN LeiQi1,FAN Jun2.& ZHANG Hui1 1State Key Laboratory of Physical chemistry of Solid Surfaces Department of chemistry,{2. of chemistry and Chemical Engineering,Xiamen university,Xiamen 361005,china 2.chool of chemistry and Environment,south china Normal university,Guangzhou 510006,china 1. State Key Laboratory of Physical chemistry of Solid Surfaces Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. School of Chemistry and Environment South China Normal University Guangzhou 510006 China

The oxalato-bridged dicopper(II) complexes [Cu2.μ-ox)(LRR)2.H2.)2.ClO4)2. (1),[Cu2.μ-ox)(LRR)2.CH3COCH3)2.ClO4)2.(1a),[Cu2.μ-ox)(LSS)2.H2.)2.ClO4)2. (2. and [Cu2.μ-ox)(LRR)(LSS)2.CH3COCH3)2.ClO4)2. (3) [LRR = (8R,10R)-(-)-[4,5]-pineno2.2.-bipyridine,LSS = (8S,10S)-(+)-[4,5]-pineno-2.2.-bipyridine;ox2. oxalate] were first prepared.A possible mechanism for the formation of the chial dicopper(II) complexes was *** on elemental analysis,conductance measurement,UV-Vis spectra,CD spectra and X-ray single-crystal diffraction,the oxalato-bridged structures of 1 and 2.were deduced to adopt two Cu(II) ions and the bridged oxalate lying in the nearly same *** crystal structures of 1a and 3 reveal that the coordination geometry around each Cu(II) ion is an elongated and distorted octahedron and two axial solvent molecules and two perchlorate ions are anti to each other respectively in both binuclear *** solution CD spectra of 1 and 2.in the visible d-d range show very weak Cotton effects with peaks at 588 and 779 nm,which are approximately of mirror image,suggesting the optical activities may be derived from the vicinal effects of the chiragenic centers at the pinene group of LRR and LSS,*** 1 has been characterized by variable-temperature magnetic susceptibility and the data was least-square fitted to the Blenaey-Bowers *** exchange integral J was found to be -338.41(4) cm-1,indicating a strong antiferromagnetic interaction between two copper(II) ions.

关键词： dicopper(II) complex chiral bipyridine μ-oxalate bridge crystal structure CD spectroscopy magnetic property