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Chinese Chemical Letters 2017年第7期28卷 1438-1446页

作者： Wei Li gao-wa Siqin Zhi Zhu Lu Qi Wen-Huai Tian Department of Materials Physics and Chemistry School of Materials Science and EngineeringUniversity of Science and TechnologyBeijing 100083China New Energy Materials and Technology Laboratory Department of Applied ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Spherical Li-rich lithium manganese oxide（LMO） spinel material was synthesized by an ion implanted method assisted by polyalcohol doped with Niobium and Phosphate *** material was characterized by scanning electron microscopy,X-ray diffraction and BET specific surface area *** electrochemical performances were investigated with galvanostatic techniques and cyclic *** synthesis process was investigated with Tg/*** results show that the lithium ion can be immersed into the pore of manganese dioxide at a low temperature with the ion implanted *** prepared materials have a higher discharge capacity and better crystallization than those prepared by solid phase *** doped Nb can improve the capacity of the Li-rich LMO spinel and reinforce the crystal growth along（111） and（400） *** crystal grains show circular and smooth morphology,which makes the specific surface area greatly ***-doped LMO spinel exhibits good high-rate capacity and structure *** prepared Li（1.09）Mn（1.87）Nb（0.031）O（3.99）（PO4）（0.021）delivers a discharge capacity of 119mAhg^-1 at 0.2C（1C=148mAg^-1） and 112.8 mAhg^-1 at 10 C,the discharge capacity retention reaches 98% at 1 ℃ after 50 cycles at 25 ℃ and 94% at 55 ℃.

关键词： Spinels Ion implantation Li-ion batteries LiMn2O4 Doping

A proto-monsoonal climate in the late Eocene of Southeast Asia:Evidence from a sedimentary record in central Myanmar

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geoscience Frontiers 2023年第1期14卷 46-63页

作者： Huasheng Huang Robert J.Morley Alexis Licht guillaume Dupont-Nivet Daniel Pérez-Pinedo Jan Westerweel Zaw Win Day wa Aung Eko Budi Lelono galina N.Aleksandrova Ramesh K.Saxena Carina Hoorn Institute for Biodiversity and Ecosystem Dynamics(IBED) University of Amsterdam1090 GE AmsterdamThe Netherlands Palynova Ltd. 1 Mow Fen RoadLittleportCambridgeshire CB61PYUK Department of Earth Sciences Royal HollowayUniversity of LondonEghamSurrey TW200EXUK Centre de Recherche et d'Enseignement de géosciences de I'Environnement(CEREgE) Aix-en-ProvenceFrance Institut fur geowissenschaften Universität Potsdam14476 PotsdamGermany géosciences Rennes CNRS and Universitéde Rennes 135042 Rennes CedexFrance geology Department Shwe Bo UniversitySagaing RegionMyanmar Department of geology University of YangonPyay RoadYangonMyanmar Badan geologi Jl.Soekarno Hatta No 444BandungBandung 40254Indonesia geological Institute Russian Academy of SciencesPyzhevsky Pereulok 7119017 MoscowRussia Birbal Sahni Institute of Palaeosciences 53 University RoadLucknow 226007India Department of Earth Sciences University of FlorenceVia G.La Pira 450121 Florenceltaly Department of Earth Sciences Memorial University of New-foundlandSt.John'sNewfoundland A1B 3X5Canada

The Burma Terrane has yielded some of the earliest pieces of evidence for monsoonal rainfall in the Bay of ***,Burmese ecosystems and their potential monsoonal imprint remain poorly *** study focuses on the late Eocene Yaw Formation(23°N)in central Myanmar,which was located near the equator(c.5°N)during the *** quantitatively assessed the past vegetation,climate,and depositional environments with sporomorph diagrams,bioclimatic analysis,and sequence *** calculated the palynological diversity and drew inferences with rarefaction analysis by compa.ing with four other middle to late Eocene tropical *** results highlight a high floristic diversity for the palynoflora throughout the section formed by six pollen zones characterized by different *** indicate that lowland evergreen forests and swamps dominated in the Eocene Burmese deltaic plains while terra firma areas were occupied by seasonal evergreen,seasonally dry,and deciduous *** vegetation pattern is typical to what is found around the Bay of Bengal today and supports a monsoon-like climate at the time of the Yaw *** analysis further suggests that in the late Eocene,the Yaw Formation was more seasonal,drier,and cooler compared to modern-day climate at similar near-equatorial *** seasonal and drier conditions can be explained by a well-marked seasonal migration of the Intertropical Convergence Zone(ITCZ),driver of proto-monsoonal *** temperatures in the late Eocene of central Myanmar may be due to the lack of adequate modern analogues for the Eocene monsoonal climate,while those found at other three Eocene Asian paleobotanical sites(India and South China)may be caused by the effect of canopy evapotranspirational *** data suggest that paleoenvironmental change including two transgressive-regressive depositional sequences is controlled by global sea level change,which may be driven by cl

关键词： Bioclimatic analysis Diversity Monsoon Palynology Sequence biostratigraphy Southeast Asia

A Computational Study of Asymmetric Hydrogenation of 2-Phenyl Acrylic Acids Catalyzed by a Rh(l) Catalyst with Ferrocenyl Chiral Bisphosphorus Ligand: The Role of Ion-Pair Interaction

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Chinese Journal of Chemistry 2021年第6期39卷 1616-1624页

作者： Xiangru Fan Lini Zheng Yuhong Yang Xiu-Qin Dong Xumu Zhang Lung-wa Chung Deportment of Chemistry Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Grubbs InstituteSouthern University of Science and TechnologyShenzhenGuangdong 518055China Key Laboratory of Biomedical Polymers Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China

Asymmetric hydrogenation reaction is one of the most efficient synthetic methods to form useful chiral compounds for synthetic chemistry,medicinal chemistry and material ***,the enantioselectivity of many hydrogenation reactions is controlled by steric hindrance between the chiral ligand and ***,Zhang group developed a highly asymmetric hydrogenation of 2-aryl and 2-alkyl acrylic acids catalyzed by a Rh(l)catalyst with a chiral Wudaphos *** excellent enantioselectivity of this asymmetric reaction was proposed to be controlled by ion-pair interaction between the substrate and chiral *** this study,a systematic density functional theory study has been carried out to investigate the reaction mechanism and origin of the *** computational results suggest that this reaction follows the classic mechanism involving oxidative addition of H_(2),migratory insertion and reductive *** from the C=C coordination to the metal in the common oxidative addition step,our study found that the chelation of the carboxyl group of the substrate to the cationic Rh(l)metal is more favorable in this oxidative addition *** high enantioselectivity is proposed to be dictated by a better catalyst/substrate geometric complementarity in the major pathway to have less distortion of the catalyst for a strong ion-pair interaction.

关键词： Hydrogenation Enantioselectivity Reaction mechanism Density functional theory Ion-pair interaction

Ureteral double J stent displaced into vena cava and management with laparoscopy: A case report and review of the literature

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World Journal of Clinical Cases 2018年第16期6卷 1160-1163页

作者： Xia-wa Mao gang Xu Jia-Quan Xiao Hui-Feng Wu Department of Urology the Second Affiliated Hospital of Zhejiang University School of Medicine

We reported displacement of a ureteral double J stent into the vena cava and laparoscopic management in a 69-year-old patient with a history of ureteral stent placement. Preoperative computed tomography and plain X-rays showed malpositioning of the double J stent and displacement into the inferior vena cava. The characteristics of stent misplacement precluded endovascular procedures and explorative laparoscopic surgery was performed. The intra-and postoperative periods were uneventful. Postoperative ima.ing demonstrated that the new double J stent was in the right position. The patient was discharged 7 d after the operation and was symptom free at the 4-mo followup.

关键词： Double J stent Displacement Inferior vena cava Laparoscopy

Effects of bark beetle pheromones on the attraction of Monochamus alternatus to pine volatiles

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Insect Science 2010年第6期17卷 553-556页

作者： Jian-Ting Fan Daniel R. Miller Long-wa Zhang Jiang-Hua Sun School of Forestry and Bio-technology Zhejiang Forestry University Lin'an Zhejiang Province China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China Southern Research Station USDA Forest Service Athens Georgia USA School of Forestry and landscape Architecture Anhui Agriculture University Hefei China

We evaluated the attraction ofMonochamus alternatus Hope （Coleoptera： Cerambycidae）, Dryocoetes luteus Blandford and Orthotomicus erosus Wollaston （Coleoptera： Curculionidae： Scolytinae） to multiple-funnel traps baited with the pine volatiles, ethanol and （＋）-α-pinene and the bark beetle pheromones, ipsenol and ipsdienol. M. alternatus were attracted to traps baited with ethanol and （＋）-α-pinene but not those baited with ipsdienol and ipsenol. Ipsdienol and ipsenol decreased catches ofM. alternatus in traps baited with ethanol and （＋）-α-pinene. Traps baited with either binary combinations of ethanol and （＋）-α-pinene or ipsdienol and ipsenol were attractive to D. luteus and O. erosus. The addition of ipsenol and ipsdienol to traps baited with ethanol and （＋）-α-pinene synergized attraction of O. erosus but not D. luteus .

关键词： bark beetle pheromones Dryocoetes luteus Monochamus alternatus Orthotomicus erosus pine volatiles

Synthesis, Crystal Structure and Characterization of a New Manganese(Ⅱ) Tetracarboxylate

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Chinese Journal of Structural Chemistry 2008年第2期27卷 167-170页

作者： Ying Shao-Ming FANg Xiao-Niu ZHANg Ding-wa CHEN Wen-Tong LIU Jiu-Hui Department of Chemistry Jinggangshan College Ji＇an Jiangxi 343009 China

By hydrothermal synthesis, a manganese（H） tetracarboxylate [Mn（2,2′-bipyridi- ne）（btec）0.5（HEO）]En （H4btec = 1,2,4,5-benzenetetracarboxylic acid） was obtained and characterized by single-crystal X-ray diffraction, IR, elemental analysis and thermogravimetric analysis. It crystallizes in triclinic, space group P1, with a = 7.721（4）, b = 8.905（5）, c = 10.712（6）A, a = 80.899（8）, β = 70.371（8）, y = 78.201（8）°, Z = 2, V= 675.8（7）A3, Mr= 354.20, De= 1.741 g/cm^3,μ = 1.007 mm^-1, F（000） = 360, S = 0.956, （△/σ）max = 0.000, the final R = 0.0490 and wR = 0.1262. This compound presents an infinite 1D polymer featuring a double-chain structure. The Mn（Ⅱ） ion is five-coordinated. The four carboxylate groups of btec4- are all deprotonated and coordinated to four Mn atoms in a monodentate fashion, forming a 1D double chain structure with a cavity. Such chains are interconnected by π-π stacking interactions into 2D layers which are further interlinked into a supramolecular structure by hydrogen bonds.

关键词： hydrothermal synthesis tetracarboxylate crystal structure double chain

Emerging roles of the neural adaptor FE65 in neurite outgrowth

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Neural Regeneration Research 2018年第12期13卷 2085-2086页

作者： Wen Li wai wa Ray Chan Jacky Chi Ki Ngo Kwok-Fai Lau Shenzhen Institute of Advanced Technology Chinese Academy of Sciences School of Life Sciences Chinese University of Hong Kong

The brain is the third largest organ in the human body and consists of over80 billion neurons（Herculano-Houzel,2009）.Neurons are interconnected by neurite to form a complex neural network that allows the communicati... 详细信息

关键词： FE Emerging roles of the neural adaptor FE65 in neurite outgrowth gEF

Syntheses,structures,and reactivity of ruthenium(Ⅱ) hydride complexes containing Klui's oxygen tripodal ligand

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Science China Chemistry 2010年第10期53卷 2139-2143页

作者： Ng Ho-Yuen LAI Chun-Sing WILLIAMS Ian D. LEUNg wa-Hung Department of Chemistry The Hong Kong University of Science and Technology

Treatment of Ru(CO)(Cl)(H)(PPh3)3 with NaLOEt (LOEt-= [CpCo{P(O)(OEt)2}3]-) afforded the hydride complex (PPh3)(CO)-LOEtRu(H) (1), which has been characterized by X-ray crystallography. Similarly, the tricyclohexylphosphine analogue, (PCy3)(CO)LOEtRu(H) (2), was synthesized from Ru(CO)Cl(H)(PCy3)2 and NaLOEt. Treatment of complex 1 with R'SO2N3 afforded the (arylsulfonyl)amido complexes LOEtRu(CO)(PPh3)(NHSO2R) (R = 2,4,6-i-Pr3C6H2 (3), 4-t-BuC6H4 (4)). The crystal structure of complex 3 has been determined. The Ru-N distance and Ru-N-S angle in 3 are 2.076(3) and 126.14(16)°, respectively. Reactions of complex 1 with acids have been studied.

关键词： ruthenium oxygen tripodal ligand hydride complex (arylsulfonyl)amido complex

Potential Impact of Climate Change on the Sediment Fluxes of a watershed in West Africa: Cas of the Aghien Lagoon, Côte d’Ivoire

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Atmospheric and Climate Sciences 2022年第1期12卷 18-30页

作者： wa Kouakou Charles N’dri Séverin Pistre Kan Jean Kouamé Jean Patrice Jourda Laboratory of Sciences and Techniques of water and Environment Felix Houphouet-Boigny University of Cocody-Abidjan Abidjan C&#244 te d’Ivoire Laboratory HSM IRD CNRS University of Montpellier Montpellier France

The semi-distributed SwaT (Soil and water Assessment Tools) model was used in this study to model the sediment yield in the watershed of the Aghien lagoon with an area of 365 km2, located in the north of the district of Abidjan (South-East from C?te d’Ivoire). A sensitivity and uncertainty analysis, as well as calibration of the SwaT model, was conducted using the Sequential Uncertainty Adjustment Procedure (SUFI-2) which is one of the programs interfaced with SwaT in the SwaT-Cup package (SwaT-Calibration-Uncertainty Programs). Five parameters of the SWAT model were found to be more sensitive to sediment fluxes. These have been modified (calibration) sparingly in order to improve the reproduction of observed sediments data. Two measures were used to assess the uncertainty analysis of the model: P-factor and R-factor. The R2 and Nash-Sutcliffe (NS) coefficients of determination were used to assess the quality of the calibration. The P-factor obtained is 0.58 and the R-factor is 2.28. The NS and R2 coefficients in calibration over the period from June 2014 to January 2015 are 0.51 and 0.86 respectively. These values indicate correct consideration of uncertainties by the model and satisfactory calibration of the SWAT model for solid fluxes. Then, the model was used to simulate the sediment fluxes at the horizons 2040 (2035-2056), 2060 (2057-2078) and 2080 (2079-2100) in order to assess the impact of climate

关键词： Abidjan Aghien Calibration Climate Change Côte d’Ivoire Sediment SUFI-2 SwaT

Synthesis of amorphous Pd-based nanocatalysts for efficient alcoholysis of styrene oxide and electrochemical hydrogen evolution

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Nano Research 2023年第4期16卷 4650-4655页

作者： Yiyao ge Jingjie ge Biao Huang Xixi wa.g guigao Liu Xiang-Huan Shan Lu Ma Bo Chen guanghua Liu Songmo Du An Zhang Hongfei Cheng Qingbo wa Shiyao Lu Lujiang Li Qinbai Yun Kuo Yuan Qinxin Luo Zhichuan J.Xu Yonghua Du Hua Zhang Department of Chemistry City University of Hong KongHong KongChina Hong Kong Branch of National Precious Metals Material Engineering Research Center(NPMM) City University of Hong KongHong KongChina Shenzhen Research Institute City University of Hong KongShenzhen 518057China Department of Chemical and Biological Engineering HKUST Jockey Club Institute for Advanced Study&Energy InstituteThe Hong Kong University of Science and TechnologyHong KongChina School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Chemistry University of Science and Technology of ChinaHefei 230026China National Synchrotron Light Source II Brookhaven National LaboratoryUptonNew York 11973USA State Key Laboratory of New Ceramics&Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Amorphous nanomaterials with long-range disordered structures could possess distinct properties and promising applications,especially in catalysis,as compared with their conventional crystalline *** is imperative to achieve the controlled preparation of amorphous noble metal-based nanomaterials for the exploration of their phase-dependent ***,we report a facile wet-chemical reduction strategy to synthesize various amorphous multimetallic Pd-based nanomaterials,including PdRu,PdRh,and *** phase-dependent catalytic performances of distinct Pd-based nanomaterials towards diverse catalytic applications have been ***,the usage of PdRu nanocatalysts with amorphous and crystalline face-centered cubic(fcc)phases can efficiently switch the ring-opening route of styrene oxide to obtain different products with high selectivity through alcoholysis reaction and hydrogenation reaction,***,when used as an electrocatalyst for hydrogen evolution reaction(HER),the synthesized amorphous PdRh nanocatalyst exhibits low overpotential and high turnover frequency values,outperforming its crystalline fcc counterpart and most of the reported Pd-based HER electrocatalysts.

关键词： amorphous nanomaterials Pd-based nanocatalysts phase engineering of nanomaterials ring-opening reaction of styrene oxide electrocatalytic hydrogen evolution