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chinese Journal of Polymer science 2002年第3期20卷 213-217页

作者： Jun wang De-min Xu Zhong-yang Liu Yong-jun Chen dong wang center for molecular science, institute of chemistry chinese academy of sciences, Beijing 100080,{3. chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

A novel ligand (3., in which the indenyl group is linked to a β-diketone moiety through a three-carbon bridge, andits titanium complex (4) were synthesized. The titanium complex was employed as a metallocene analog with co-catalystmethylaluminoxane (MAO) in catalytic syndiospecific polymerization of styrene to give highly syndiotactic polystyrene(s-PS, 96%-97%). Polymerization temperature (T_p) strongly influenced the catalytic activity and syndiotacticity of theproduced PS. The activities of catalyst 4 increase from 1.84×10~6 to 3.26×10~6 gPS/molTi·h with the increase of T_p from60℃ to 80℃ and the syndiotacticities of the produced s-PS also increase slightly. Then, both the catalytic activity and thesyndiotacticity of PS decrease at T_p of 90℃.

关键词： β-Diketone Metallocene Syndiospecific polymerization Polystyrene

Low dipole moment large β electrooptic chromophores based on exocyclic double bond conjugated bridge

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chinese science Bulletin 2001年第18期46卷 1517-1522页

作者： wang Peng, LI Shaojun & YE Chengcenter for molecular {3., Organic Solids Laboratory, institute of chemistry, chinese academy of sciences, Beijing 100080, china center for molecular science Organic Solids Laboratory Institute of Chemistry Chinese Academy of Sciences Beijing China

Novel low dipole moment (μ) and large first hyperpolarizability (β) electrooptic chromophores have been designed based on the special characteristic of reversed dipole moment in the excited state of exocyclic double bond (ECDB) conjugated bridge by the optimization of the substituted method, and their electronic and second-order nonlinear optical properties have been theoretically investigated by employing the AM1/FF and ZINDO/S-CI approaches. By extending the conjugation length and optimizing the donor/acceptor strength, the oscillator strength of the excited transition that contributes to the molecular nonlinearity can be further enhanced. The designed chromophores possess a larger figure of merit (FOM) than that of 4-N,N-dimethylamino-4’-nitrostilbene (DANS), and lower (5 D) ground state dipole *** low dipole moment (μ) and large first hyperpolarizability (β) electrooptic chromophores have been designed based on the special characteristic of reversed dipole moment in the excited state

关键词： AM1/FF ZINDO/S-CI molecular design dipole moment (μ) first hyperpolarizability (β) exocyclic double bond.

CHIRAL CONJUGATED OLIGOMER BASED ON 1,1’-BINOL WITH 3.3.-ACETYLENE-PHENYLENE-ACETYLENE SPACER

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chinese Journal of Polymer science 2001年第5期19卷 521-526页

作者： Tian-jun Liu Ke-shen Zhang Yong-jun Chen dong wang Chao-jun Li center for {3. science, institute of chemistry chinese academy of sciences, Beijing 100080 china Department of chemistry Tulane University New Orleans, LA 70118 U.S.A. chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China Tulane Univ Dept Chem New Orleans LA 70118 USA

The 1,2'-binaphthol based oligomers 3.and 7 with 3.3.-acetylene-phenylene-acetylene spacer were prepared from BINOL 1. The high optical rotation value and CD spectra demonstrated the main chain chirality of the oligomer molecule. The UV-VIS and fluorescent spectra evidence the characteristics of conjugated structure. In comparison with oligomer 2 bearing 3.3.-acetylene spacer, the oligomers 3.and 7 have longer efficient conjugation segment, and their fluorescent quantum yields (phi) increased (0.60-0.65 versus 0.14). Extending the effective conjugation segment would improve the photophysical properties of chiral conjugated polymers.

关键词： chiral conjugated oligomer BINOL 3.3.'-acetylene-phenylene-acetylene spacer

Observation of contrast variations of a copper(Ⅱ)complex by scanning tunneling microscopy

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chinese science Bulletin 2003年第6期48卷 531-534页

作者： wang Zhigang, ZENG Qingdao, wang Chen, ZHOU Chunqing, WAN Lijun & BAI Chunli The center for {3. sciences, institute of chemistry, chinese academy of sciences, Beijing 100080, china The center for molecular sciences Institute of Chemistry Chinese Academy of Sciences Beijing China

This report presents experimental observations of dramatic variations in STM images of bis [1,3. di(p-n-tetradecyloxyphenyl)propane-1,3.dionato] copper(Ⅱ) (abbreviated to C14O-Cu) physisorbed on HOPG as the bias voltage is changed. Several representative image patterns were obtained for the rich changes of the internal contrast of the molecule. Submolecular features of the molecular cores and the interdigitated alkyl parts are clearly visible.

关键词：扫描隧道显微镜铜配合物实验观察对比度变化 STM图像吸附物

Assessing the dynamics of O2 desorption from cobalt phthalocyanine by in situ electrochemical scanning tunneling microscopy

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Journal of Energy chemistry 2024年第11期98卷 144-148页

作者： Yu-Qi wang Yue Feng Xiang wang dong wang CAS Key Laboratory of molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular Sciences Beijing National Laboratory for Molecular Science (BNLMS) Institute of Chemistry Chinese Academy of Sciences University of chinese academy of sciences

We report here the in situ electrochemical scanning tunneling microscopy（ECSTM） study of cobalt phthalocyanine（CoPc）-catalyzed O2evolution reaction（OER） and the dynamics of *** self-assembled CoPc monolayer is fabricated on Au（111） substrate and resolved by ECSTM in 0.1 M KOH *** OH-adsorption on CoPc prior to OER is observed in ECSTM *** OER,the generated O2adsorbed on Co Pc is observed in the CoPc *** step experiment is employed to monitor the desorption of OER-generated O2from CoPc,which results in the decreasing surface coverage of CoPc-O2with *** rate constant of O2desorption is evaluated through data *** insights into the dynamics of Co-O2dissociation at the molecular level via in situ imaging help understand the role of Co-O2in oxygen reduction reaction（ORR） and OER.

关键词： Cobalt phthalocyanine Electrochemical scanning tunneling microscopy Oxygen evolution reaction

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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science china chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, wang Jin3. WU Yishi1, YUAN Gu3. AI Xicheng1, wang Li4 & ZHANG Jianping1 1. State Key Laboratory for Structural chemistry of Unstable and Stable Species, {3. of chemistry, chinese academy of sciences, Beijing 100080, china 2. School of Life science and Technology, Beijing {3. of Technology, Beijing 100081, china 3. College of chemistry and {13. Engineering, Peking University, Beijing 100080, china 4. center for Condensed Matter Physics, {3. of Physics, chinese academy of sciences, Beijing 100080, china Correspondence should be addressed to Ai Xicheng and Zhang Jianping 1. State Key Laboratory for Structural chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. School of Life science and Technology Beijing Institute of Technology Beijing 100081 China 3. College of chemistry and molecular Engineering Peking University Beijing 100080 China 4. center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 3. ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

Quasi-solid-state nanocrystalline TiO2 solar cells using gel network polymer electrolytes based on polysiloxanes

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chinese science Bulletin 2003年第7期48卷 646-648页

作者： LI Weiying, KANG Junjie, LI Xueping, FANG Shibi, LIN Yuan, wang Guiqiang & XIAO Xurui center for molecular {3., institute of chemistry, chinese academy of sciences, Beijing 100080, china 1. center for molecular science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

A quasi-solid-state dye-sensitized nanocrystal-line porous TiO2 film solar cell was fabricated using a novel gel network polymer electrolyte based on polysiloxanes with both polyethylene oxide internal plasticized side chains and quaternary ammonium groups. The cell exhibited better photoelectrical conversion performance under 60 mW/cm2 irradiation. The short photocurrent (Isc) of 5.0 mA/cm2 and open voltage (Voc) of 0.68 V were achieved, and the energy conversion efficiency (h ) and fill factor (ff) were 3.4% and 0.60, respectively.

关键词：类固态TiO2太阳能电池凝胶网状聚合体电解液染色敏化二氧化钛薄膜

Biomimetic MXene membranes with negatively thermo-responsive switchable 2D nanochannels for graded molecular sieving

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Green Energy & Environment 2024年第6期9卷 1058-1067页

作者： Yi wang Yangyang wang Chang Liu dongjian Shi Weifu dong Baoliang Peng Liangliang dong Mingqing Chen The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxiJiangsu214122China International Research center for Photo-responsive Molecules and Materials Jiangnan UniversityWuxiJiangsu214122China Research institute of Petroleum Exploration&Development(RIPED) PetroChina/Key Laboratory of Oilfield ChemistryCNPCBeijing100083China

Negatively thermo-responsive 2D membranes,which mimic the stomatal opening/closing of plants,have drawn substantial interest for tunable molecular separation ***,these membranes are still restricted significantly on account of low water permeability and poor dynamic tunability of 2D nanochannels under temperature ***,we present a biomimetic negatively thermo-responsive MXene membrane by covalently grafting poly(N-isopropylacrylamide)(PNIPAm)onto MXene *** uniformly grafted PNIPAm polymer chains can enlarge the interlayer spacings for increasing water permeability while also allowing more tunability of 2D nanochannels for enhancing the capability of gradually separating multiple molecules of different *** expected,the constructed membrane exhibits ultrahigh water permeance of 95.6 L m^(-2) h^(-1) bar^(-1) at 25℃,which is eight-fold higher than the state-of-the-art negatively thermoresponsive 2D ***,the highly temperature-tunable 2D nanochannels enable the constructed membrane to perform excellent graded molecular sieving for dye-and antibiotic-based ternary *** strategy provides new perspectives in engineering smart 2D membrane and expands the scope of temperature-responsive membranes,showing promising applications in micro/nanofluidics and molecular separation.

关键词： Thermo-responsive 2D membrane MXene nanosheets PNIPAm Temperature-tunable 2D nanochannels Graded molecular sieving

Key Conditions in Capillary Electrophoresis of Amino Acids with Indirect Ultraviolet Detection

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chinese Chemical Letters 2000年第9期11卷 803-806页

作者： Zhi Xin wang Yi CHEN Qing GUO center for molecular {3.. institute of chemistry. The Chincse academy of sciences. Beijing 100080 chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

Key factors for capillary electrophoresis of amino acids with indirect ultraviolet detection were illustrated. Buffer compositions and additives were found to be influential as expected, while buffer pH was shown to be particularly critical to the separation and detection. The effect of pH also depended on the electrophoretic mode used. Ways to obtain recurring and selective were suggested.

关键词： amino acids capillary electrophoresis indirect ultraviolet detection

Organic single crystals or crystalline micro/nanostructures: Preparation and field-effect transistor applications

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science china chemistry 2010年第6期53卷 1225-1234页

作者： FU XiaoLong,wang ChengLiang,LI RongJin,dong HuanLi & HU WenPing Beijing National Laboratory for molecular {3.,Key Laboratory of Organic Solids,institute of chemistry,chinese academy of {3.,Beijing 100190,china 1. Beijing National Laboratory for molecular sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Organic single crystals hold great promise for the development of organic semiconductor materials,because they could reveal the intrinsic electronic properties of these materials,providing high-performance electronic devices and probing the structureproperty *** article reviews the preparation methods for organic single crystals or crystalline micro/nanostructures,including vapor phase growth methods and solution-processed methods,and summarizes a few methods employed in the fabrication of field-effect transistors along with dozens of examples concerning both small molecules and polymers with high field-effect performance.

关键词： organic single crystal physical vapor transport (PVT) solution-processed technique field-effect transistors (FETs) micro/nanostructures