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Science china chemistry 2008年第2期51卷 120-127页

作者： WEI RuiPing1,2. GU YanBo1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented chemical engineering, College of {2. and chemical engineering, nanjing Uni- versity of Technology, nanjing 2.0009, china 2.College of {2. and chemical engineering, Southeast University, nanjing 2.1189, china State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical EngineeringNanjing University of TechnologyNanjing 210009China College of chemistry and chemical {2. Southeast UniversityNanjing 211189China

The bimetal-bearing (CePt or LaPt) 12.tungstophosphoric acid (H3PW12.40 (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H2.chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 2.0℃ and WHSV of 1.4 h1, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%.

关键词： hydroisomerization of n-heptane bimetal catalyst heteropoly acid USY platinum

Optical applications of quantum dots in biological system

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Science china chemistry 2011年第8期54卷 1177-1184页

作者： WANG Wei & ZHU Jun-Jie State Key Laboratory of Analytical chemistry for Life Science school of chemistry and chemical engineering, {2. University, nanjing 2.0093, china 1. State Key Laboratory of Analytical chemistry for Life Science school of chemistry and chemical engineering Nanjing University Nanjing 210093 China

This review presents a simple introduction on the unique properties and general synthesis of quantum dots (QDs) in which we lay emphasis on the optical applications in the biological system. The detection of biological molecules such as DNA, protein and enzyme, the cell-based analysis and in vivo animal imaging are mainly discussed.

关键词： quantum dots optical application biological system

One-dimensional metal phosphonates based on 6-phosphononicotinic acid:A structural and magnetic study

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Science china chemistry 2010年第10期53卷 2112-2117页

作者： WANG PengFei, DUAN Yan & ZHENG LiMin State Key Laboratory of Coordination chemistry Coordination chemistry Institute, {2., nanjing University, nanjing 2.0093, china 1. State Key Laboratory of Coordination chemistry Coordination chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

The reactions of 6-phosphononicotinic acid (pnaH3) and metal salts result in three new compounds, namely, M(pnaH)-(H2.)3·H2. [M = Co(Ⅱ) (1), Ni(Ⅱ) (2., Zn(Ⅱ) (3)]. These compounds are isostructural and contain 2. helical chains made up of corner-sharing {MO5N} octahedra and {PO3C} tetrahedra. The chains are further connected by extensive hydrogen bonds to form a three-dimensional supramolecular structure. Magnetic studies reveal that dominant antiferromagnetic interactions are mediated in both 1 and 2. Interestingly the dehydrated compound 1 shows metamagnetic behavior at low temperature.

关键词： carboxylate-phosphonate coordination polymer magnetic property metamagnetism

Polymer-assisted nanoparticulate contrast-enhancing materials

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Science china chemistry 2010年第3期53卷 479-486页

作者： DING Yin1,3,HU Yong2.WU Wei1 & JIANG XiQun1 1Laboratory of Mesoscopic chemistry and Department of Polymer Science and engineering,College of chemistry & chemical engineering,nanjing University,nanjing 2.0093,china 2.ational Laboratory of Solid State Microstructure,Department of Material Science and engineering,nanjing University,nanjing 2.0093,china 3Key Laboratory of Analytical chemistry for Life Science,Ministry of Education,school of chemistry and chemical engineering,nanjing University,nanjing 2.0093,china 1. Laboratory of Mesoscopic chemistry and Department of Polymer Science and engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing 210093 China3. Key Laboratory of Analytical Chemistry for Life Science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China2. National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing 210093 China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and *** fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of *** photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching *** nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and *** potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this *** modification of inorganic nanoparticles could enhance their biostability in physiological conditions and ability of targeting bioactive molecules.

关键词： contrast agent cell image gold nanoparticles iron oxide nanoparticles carbon nanotubes polymeric-inorganic hybrid nanoparticles

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Science china chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. Department of chemistry, nanjing University of Science and Technology, nanjing 2.0094, china 2. Institute of chemical Materials, china Academy of engineering Physics, Mianyang 62.900, china 1. Department of chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Institute of chemical Materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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Science china chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1,2.SUN Hao2.LIN Chen2.ZHANG GuangQian2.LI GuiGen4 & PAN Yi2.3 1 Department of chemistry,Huaiyin Normal University,Huai’an 2.1003,china 2.{2.,nanjing University,nanjing 2.0093,china 3 State Key Lab of Coordination chemistry,nanjing University,nanjing 2.0093,china 4 Department of chemistry and Biochemistry,Texas Tech University,Lubbock,Texas 79409-1061,USA 1. Department of chemistry Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS

Syntheses,crystal structures and properties of three novel coordination polymers with tripodal imidazole-containing ligands and benzenetetracarboxylate

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Science china chemistry 2010年第10期53卷 2164-2169页

作者： SU Zhi, FAN Jian & SUN WeiYin State Key Laboratory of Coordination chemistry nanjing National Laboratory of Microstructures Coordination chemistry Institute, school of chemistry and chemical engineering, nanjing University, nanjing 2.0093, china 1. State Key Laboratory of Coordination chemistry nanjing National Laboratory of Microstructures Coordination chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

Three novel coordination polymers, [Ni2.tib)2.btec)]·2.2. (1), [Co2.tib)2.btec)]·2.2. (2. and [Zn4(tib)2.btec)Cl4]·2.2. (3), have been synthesized by using mixed ligands of 1,3,5-tris(1-imidazolyl)benzene (tib) and 1,2.4,5-benzenetetracarboxylic acid (H4btec) under hydrothermal conditions. Complexes 1 and 2.have the same structure and are rare three-dimensional (3D) self-penetrating (3,4,5)-connected nets, while complex 3 is an unprecedented (3,4)-connected 3D net. The different structures of 1 (2. and 3 are ascribed to the distinct coordination geometry of the metal centers. The thermal stability and photoluminescence property of the complexes were investigated.

关键词： coordination polymer self-penetration crystal structure thermal stability photoluminescence property

Size effect of fullerene cages and encaged clusters in M3N@C2.

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Science china chemistry 2009年第5期52卷 584-589页

作者： GAN LiHua school of chemistry and chemical engineering, Southwest University, Chongqing 400715, china school of chemistry and chemical engineering Southwest University Chongqing 400715 China

Based on the calculated findings that the sizes of encaged clusters determine the structures and the stability of C80-based trimetallic nitride fullerenes (TNFs), more extensive density functional theory calculations were performed on M3N@C68, M3N@C78 and M3N@C80 (M=Sc, Y and La). The calculated results demonstrated that the structures and stability undergo a transition with the increasing of the sizes of the cages and clusters. Sc3N is planar inside the three considered cages, Y3N is slightly pyramidal inside C68-6140 and C78-5 and planar inside I h C80-7, however, La3N is pyramidal inside all the three cages. Those cages with pyramidal clusters inside deformed considerably, compared with their parent cages. In these cases, the bonding of metallic atoms toward the cages does not play an impor-tant role, and the encaged cluster tends to be located inside the cages with the largest M-M and M-C distances so that the strain energy can be released mostly. These calculations revealed the size effect of fullerene cages and encaged clusters, and can explain the position priority of M3N inside fullerene cages and the differences in yield of M3N@C2..

关键词： trimetallic nitride fullerenes (TNFs) density functional theory (DFT) size effect stability

Synthesis and Lubrication of Phosphorylcholine Derivative

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Journal of Bionic engineering 2010年第3期7卷 254-258页

作者： Zhenliang Qiao~1, Dangsheng Xiong~1, Lude Lu~2. Pengju Jiang~2.1. Department of Materials Science and engineering, nanjing University of Science and Technology, nanjing 2.0094, P.R. china 2. school of chemical engineering, nanjing University of Science and Technology, nanjing 2.0094, P. R. china [a] Department of Materials Science engineering Nanjing University of Science Technology Nanjing 210094 P.R. China [b] School of Chemical Engineering Nanjing University of Science Technology Nanjing 210094 P. R. China

The monomer of phosphorylcholine derivative, O-(5-（2.methacryloxy）-3, 3-dimethyl-3-azapentyl)-O’-（ω-hydroxy-octyl）-phosphatequaternary ammonium salt, was designed and synthesized successfully. It was characterized by the spectra ofHNMR and Mass spectra （ESI+）, and every signal was assigned. Then the lubricating characteristics of the phosphorylcholinederivative were investigated on the tribological setup of ball-oh-flat. The Ultra-High Molecular Weight Polyethylene（UHMWPE） flat was rotated against a stainless steel ball with 6 mm diameter. The load was 2.3 N, which corresponded to amaximal Hertz contact pressure of 2. MPa. Water, phosphorylcholine derivative, and Acrylic Acid （AA） solution were used aslubricants, respectively. Compared with AA, the phosphorylcholine derivative shows significant lubrication. It can be stronglyhydrated under water due to the charged segment in chemical structure. The thick water layers within the chains serves asboundary lubricants, and this is thought to be the molecular origins of lubricating behavior.

关键词： artificial joint articular cartilage molecular lubrication mechanism phosphorylcholine synthesis UHMWPE

Theoretical study of bifurcated bent blue-shifted hydrogen bonds CH_2.Y

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Science china chemistry 2008年第7期51卷 623-631页

作者： LI AnYong school of chemistry and chemical engineering, Southwest University, Chongqing 400715, china school of chemistry and chemical engineering Southwest UniversityChongqing 400715China

Ab initio quantum chemistry methods were applied to study the bifurcated bent hydrogen bonds Y… H2.Z (Z = O, S, Se) and Y…H2.Z2.(Z = F, Cl, Br) (Y = Cl-, Br-) at the MP2.6-311++G(d,p) and MP2.6-311++G(2.f,2.) levels. The results show that in each complex there are two equivalent blue-shifted H-bonds Y…H—C, and that the interaction energies and blue shifts are large, the energy of each Y…H—C H-bond is 15-2. kJ/mol, and Δr(CH) = -0.1 - -0.5 pm and Δv(CH) = 30 - 80 cm-1. The natural bond orbital analysis shows that these blue-shifted H-bonds are caused by three factors: large rehybridization; small direct intermolecular hyperconjugation and larger indirect intermolecular hy- perconjugation; large decrease of intramolecular hyperconjugation. The topological analysis of elec- tron density shows that in each complex there are three intermolecular critical points: there is one bond critical point between the acceptor atom Y and each hydrogen, and there is a ring critical point inside the tetragon YHCH, so these interactions are exactly H-bonding.

关键词： bifurcated bent H-bonds blue-shifted H-bonds topological property of electron density intramolecular hyperconjugation