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Nano Research 2010年第5期3卷 350-355页

作者： Hui Cao Jing Ma Yi Luo Department of Theoretical chemistry School of BiotechnologyRoyal Institute of TechnologyS-10691 StockholmSweden School of chemistry and Chemical Engineering Institute of Theoretical and Computational ChemistryKey Laboratory of Mesoscopic Chemistry of Ministry of EducationNanjing UniversityNanjing 210093China

We have combined molecular dynamics simulations with first-principles calculations to study electron transport in a single molecular junction of perylene tetracarboxylic diimide (PTCDI) in aqueous solution under external electric gate fields. It is found that the statistics of the molecular conductance are very sensitive to the strength of the electric field. The statistics of the molecular conductance are strongly associated with the thermal fluctuation of the water molecules around the PTCDI molecule. Our simulations reproduce the experimentally observed three orders of magnitude enhancement of the conductance, as well as the temperature dependent conductance, under the electrochemical gates. The effects of the molecular polarization and the dipole rearrangement of the aqueous solution are also discussed.

关键词： Molecular junction field effect solvent effect temperature effect statistical behavior

Synthesis and Crystal Structure of [{Mn(IBG)(2,2'-bipy)(H_2O)}·4H_2O]_n

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Chinese Journal of Structural chemistry 2010年第3期29卷 483-487页

作者：徐涵李一志 Huangshan University Coordination chemistry institute State Key Laboratory of Coordination ChemistryCollege of Chemistry and Chemical EngineeringNanjing University

A novel MnⅡ complex [{Mn（IBG）（2,2＇-bipy）（H2O）}·4H2O]n 1（H2IBG=isophtha-loylbisglycine and 2,2＇-bipy = 2,2＇-bipyridine） has been synthesized and characterized by singlecrystal X-ray diffraction,elemental analysis,IR spectra and thermogravimetric analysis.It crystallizes in monoclinic,space group P21/n,with a=13.667（2）,b=14.045（2）,c=14.195（2）,β=101.483（3）°,V=2670.1（7）3,Z=4,C22H26N4O11Mn,Mr=577.41,Dc=1.436 g/cm3,F（000）=1196.0,μ（MoKα）=0.558 mm-1,the final R=0.0578 and wR=0.1460 for 2974 observed reflections with I2σ（I）.In the structure,the MnⅡ atom is coordinated in a distorted octahedral environment arranged by one water molecule,one 2,2＇-bipy ligand and two IBG ligands.

关键词： manganese complex crystal structure hydrogen bond

Palladium-catalyzed relay C–H functionalization to construct novel hybrid-arylcyclophosphorus ligand precursors

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Chinese Chemical Letters 2022年第5期33卷 2397-2401页

作者： Juan Wang Peng-Bo Bai Shang-Dong Yang State Key Laboratory of Applied Organic chemistry Lanzhou UniversityLanzhou 730000China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

A new relay C–H functionalization of di([1,1'-biphenyl]-2-yl)phosphine oxide to obtain esterified and hy-droxylated products with different hypervalent iodines as oxidants under palladium catalysis is disclosed.This reaction provides a more effective and concise strategy for the synthesis of novel structural hybrid-arylcyclophosphorus ligand precursors with a wide range of substrates and good functional group toler-ance.

关键词： Palladium catalyst Cyclization Acetylation Hydroxylation Dibenzophosphorus oxide

Copper nanowires decorated with TiO_(2−x) from MXene for enhanced electrocatalytic nitrogen oxidation into nitrate under vacuum assistance

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Nano Research 2023年第10期16卷 12357-12362页

作者： Quan Li Zhengting Xiao Weina Jia Qin Li Xianguo Li Wentai Wang Key Laboratory of Marine chemistry Theory and Technology Ministry of EducationCollege of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101China Queensland Micro-and Nanotechnology Centre School of Engineering and Built EnvironmentGriffith University Nathan CampusBrisbaneQLD 4111Australia

The green synthesis of nitrate(NO_(3)^(−))via electrocatalytic nitrogen oxidation reaction(NOR)is a promising strategy for artificial nitrogen fixation,which shows great advantages than traditional nitrate synthesis based on Haber–Bosch and Ostwald processes.But the poor N_(2)absorption,high bond energy of N≡N(941 kJ·mol^(−1)),and competing multi-electron-transfer oxygen evolution reaction(OER)limit the activity and selectivity.Herein,we fabricated MXene-derived irregular TiO_(2)−x nanoparticles anchored Cu nanowires(Cu-NWs)electrode for efficient electrocatalytic nitrogen oxidation,which exhibits a NO_(3)−yield of 62.50μg·h^(−1)·mgcat^(−1)and a Faradaic efficiency(FE)of 22.04%,and a significantly enhanced NO_(3)−yield of 92.63μg·h^(−1)·mgcat^(−1),and a FE of 40.58%under vacuum assistance.The TiO_(2)−x/Cu-NWs electrode also shows excellent reproducibility and stability under optimal experimental conditions.Moreover,a Zn-N_(2)reaction device was assembled with TiO_(2−x)/Cu-NWs as an anode and Zn plate as a cathode,obtaining an extremely high NO_(3)−yield of 156.25μg·h^(−1)·mgcat^(−1).The Zn-nitrate battery shows an open circuit voltage(OCV)of 1.35 V.This work provides novel strategies for enhancing the performance of ambient N_(2)oxidation to obtain higher NO_(3)^(−)yield.

关键词： nitrogen oxidation nitrate production electrocatalysis Zn-N_(2)system Zn-nitrate battery vacuum assistance

Synthesis and Crystal Structure of [{Cd(hmbdc)(H_2O)_3}·2H_2O]_n

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Chinese Journal of Structural chemistry 2007年第4期26卷 423-426页

作者：胡月华王燕王作为李一志郑和根 Huangshan University Coordination chemistry institute State Key Laboratory of Coordination Chemistry College of Chemistry and Chemical Engineering Nanjing University Fujian institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A novel coordination polymer [{Cd（hmbdc）（H20）3}-2H20],, （hmbdc = 5-hydroxyisophthalic acid） has been synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P2Jc, with a = 9.599（3）, b = 18.699（5）, c = 7.557（2） A, r= 108.198（4）°, V= 1288.6（6） A3, Z= 4, M,.= 382.60, Dc = 1.972 g/cm^, F（000） = 760, p = 1.740, the final R =0.0555 and wR = 0.0995 for 1732 observed reflections with 1 〉 2σ（I）. The structural analysis shows that the intermolecular hydrogen bonds and π-π interactions result in a three-dimensional supramolecular framework.

关键词： Cd（Ⅱ） complex crystal structure hydrogen bond network structure

Create Rich Oxygen Defects of Unique Tubular Hierarchical Molybdenum Dioxide to Modulate Electron Transfer Rate for Superior High-Energy Metal-Ion Hybrid Capacitor

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Energy & Environmental Materials 2023年第3期6卷 193-204页

作者： Heng Zhang Jinggao Wu Zhuo Zou Youcun Bai Chao Wu Qingxin Zeng Feng Liu Wei Shen Jian Jiang Chang Ming Li institute of Clean Energy and Advanced Materials School of Materials and energySouthwest UniversityChongqing 400715China Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies Chongqing 400715China Key Laboratory of Rare Earth Optoelectronic Materials&Devices College of Chemistry and Materials EngineeringHuaihua UniversityHuaihua 418000China School of chemistry and Chemical Engineering Chongqing UniversityChongqing 401331China institute of Materials Science and Devices School of Materials Science and EngineeringSuzhou University of Science and TechnologySuzhou 215011China

Metal-ion capacitors could merit advantages from both batteries and capacitors,but they need to overcome the severe restrictions from their sluggish reaction kinetics of the battery type electrode and low specific capacitance of capacitor type electrode for both high energy and power density.Herein,we use the Kirkendall effect for the first time to synthesize unique tubular hierarchical molybdenum dioxide with encapsulated nitrogen-doped carbon sheets while in situ realizing phosphorus-doping to create rich oxygen vacancies(P-MoO_(2-x)@NP-C)as a sodium-ion electrode.Experimental and theoretical analysis confirm that the P-doping introduced oxygen defects can partially convert the high-bond-energy Mo–O to low-bond-energy Mo–P,resulting in a low oxidation state of molybdenum for enhanced surface reactivity and rapid reaction kinetics.The as-prepared P-MoO_(2-x)@NP-C as an ion-battery electrode is further used to pair active N-doped carbon nanosheet(N-C-A)electrode for Na-ion hybrid capacitor,delivering excellent performance with an energy density of 140.3 Wh kg^(−1),a power density of 188.5 W kg^(−1)and long stable life in non-aqueous solution,which ranks the best among all reported MoO x-based hybrid capacitors.P-MoO_(2-x)@NP-C is also used to fabricate a zinc-ion hybrid capacitor,also accomplishing a remarkable energy density of 43.8 Wh kg^(−1),a power density of 93.9 W kg^(−1),and a long stable life@2A g^(−1)of 32000 cycles in aqueous solutions,solidly verifying its universal significance.This work not only demonstrates an innovative approach to synthesize high-performance metal ion hybrid capacitor materials but also reveals certain scientific insights into electron transfer enhancement mechanisms.

关键词： molybdenum dioxide oxygen vacancies phosphorus incorporation sodium-ion hybrid capacitor Zinc-ion hybrid capacitor

CRYSTALLIZATION KINETICS OF HOMOGENEOUS AND HETEROGENEOUS LLDPE

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Chinese Journal of Polymer Science 2002年第4期20卷 339-345页

作者： Hong-xiang Teng Wen-hong Tang Yi Shi Xi-gao Jin State Key Laboratory of Polymer Physics and chemistry Center for Molecular Science, institute of chemistry Chinese Academy of Sciences Beijing 100080 China Department of chemistry Jilin University Changchun 130023, China Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Polymer Physics and Chemistry 北京 100080 Department of chemistry Jilin University Changchun 130023

Based on thermal analysis, the isothermal and nonisothemal crystallization kinetics of Ziegler-Natta catalyzed linear low density polyethylene (Z-N LLDPE) and metallocene catalyzed LLDPE (m-LLDPE) were studied. Treating the results with the Avrami equation and the Ozawa equation, the crystallization constant Igk and the Avrami exponent n were obtained. Some other crystallization parameters were also discussed. According to the different characteristics of the chain structures of Z-N LLDPE and metallocene LLDPE, their crystallization behaviors were analyzed. It is indicated that the homogeneity and heterogeneity of the two polymers act in different way during the crystallization process of polymers, including the nucleation and the growth of crystals under various conditions.

关键词： crystallization kinetics homogeneity heterogeneity LLDPE

Unveiling bulk and surface radiation forces in a dielectric liquid

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Light(Science & Applications) 2022年第5期11卷 925-934页

作者： N.G.C.Astrath G.A.S.Flizikowski B.Anghinoni L.C.Malacarne M.L.Baesso T.Požar M.Partanen I.Brevik D.Razansky S.E.Bialkowski Department of Physics Universidade Estadual de MaringáMaringáPRBrazil Faculty of Mechanical Engineering University of LjubljanaLjubljanaSlovenia Department of Electronics and Nanoengineering Aalto UniversityAaltoFinland Department of Energy and Process Engineering Norwegian University of Science and TechnologyTrondheimNorway institute for Biomedical Engineering and institute of Pharmacology and Toxicology Faculty of MedicineUniversity of ZurichZurichSwitzerland institute for Biomedical Engineering Department of Information Technology and Electrical EngineeringETH ZurichZurichSwitzerland Department of chemistry and Biochemistry Utah State UniversityLoganUTUSA

Precise control over light-matter interactions is critical for many optical manipulation and material characterization methodologies,further playing a paramount role in a host of nanotechnology applications.Nonetheless,the fundamental aspects of interactions between electromagnetic fields and matter have yet to be established unequivocally in terms of an electromagnetic momentum density.Here,we use tightly focused pulsed laser beams to detect bulk and boundary optical forces in a dielectric fluid.From the optical convoluted signal,we decouple thermal and nonlinear optical effects from the radiation forces using a theoretical interpretation based on the Microscopic Ampère force density.It is shown,for the first time,that the time-dependent pressure distribution within the fluid chiefly originates from the electrostriction effects.Our results shed light on the contribution of optical forces to the surface displacements observed at the dielectric air-water interfaces,thus shedding light on the long-standing controversy surrounding the basic definition of electromagnetic momentum density in matter.

关键词： dielectric momentum surface

Michael addition-based cyclization strategy in the total synthesis of Lycopodium alkaloids

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Science China chemistry 2016年第9期59卷 1079-1087页

作者： Lin-Rui Zhong Zhu-Jun Yao State Key Laboratory of Coordination chemistry Institute of Chemical Biology and Drug Innovation School of Chemistry and Chemical Engineering Collaborative Innovation Center of Chemistry for Life Sciences Nanjing University

Lycopodium alkaloids, a unique family of biologically important natural products isolated and characterized from various species of Lycopodium(sensu lato), have attracted extensive attention from chemists and pharmacists in the past three decades. Michael addition-based cyclization has been successfully employed as an elegant and efficient ring-construction protocol of constructing key cyclohexanone intermediates in the total synthesis of Lycopodium alkaloids. This mini-review chooses and summarizes several representative total syntheses of various Lycopodium alkaloids in which intramolecular Michael addition severed as the key methodology.

关键词：加成环化生物碱全合成石松天然产物生物学化学家环己酮

Sodium Amalgam, a Useful Reducing Reagent for Formation of Amines from Azides Bearing a Variety of Functional Groups

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Chinese Journal of chemistry 2005年第12期23卷 1637-1640页

作者：陆标谢小安朱继东马大为 Department of chemistry Fudan University Shanghai 200433 China State Key Laboratory of Bioorganic and Natural Products chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

到没有保护的动人的本甲基， t-butyldimethylsilyl ， t-butyldiphenylsilyl ， trityl 和 tetrahydropyranyl 醚的胺的叠氮化物的减小组织， CC 双、三倍的债券，以及芳香的溴化物和 nitrile 功能的组，吗在温度在甲醇作为减少的试剂... 详细信息

到没有保护的动人的本甲基， t-butyldimethylsilyl ， t-butyldiphenylsilyl ， trityl 和 tetrahydropyranyl 醚的胺的叠氮化物的减小组织， CC 双、三倍的债券，以及芳香的溴化物和 nitrile 功能的组，吗在温度在甲醇作为减少的试剂用钠汞齐被完成从? 40 ??乃????㈠崠㈠?丠?????箬?????佃?″嬩匠???‵??″崩㈠素㈠?㈠???????匠????㈠?????吗?低″崩?″？？

关键词：钠汞合金胺功能团叠氮化物