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Nickel(Ⅱ) a-Diimine Catalysts with Carboxyl Groups for Ethylene Oligomerization and Polymerization

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Chinese Journal of Polymer Science 2016年第2期34卷 221-228页

作者： Bing Liu Meng-zhe fang 介素云 Zhi-yang Bu Bo-Geng Li State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

A series of nickel（II） α-diimine complexes with strong electron-withdrawing carboxyl groups, having reactive hydrogen atoms, were prepared and used as precatalysts for ethylene oligomerization and/or polymerization. The influence of metal halides and ligand structure on the catalytic activity and properties of products was investigated. The results showed that nickel bromide was much more active than nickel chloride, and the substituents at the ortho-position of aryl ring had large influence on the properties of products. Therefore, the products ranging from liquid oligomers to polymers could be readily obtained by the variation of the substituents on the ligands and reaction conditions.

关键词： α-Diimine Nickel Ethylene Oligomerization Polymerization.

Novel Ni_(3)S_(4)/NiS/NC composite with multiple heterojunctions synthesized through space-confined effect for high-performance supercapacitors

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International Journal of Extreme Manufacturing 2023年第1期5卷 318-329页

作者： Wutao Wei Zijie Guo Jiaqiang Xu zhe fang Jiujun Zhang Yu Jia Liwei Mi Institute for Sustainable Energy College of SciencesShanghai UniversityShanghai 200444People’s Republic of China Henan Key Laboratory of Functional Salt Materials Center for Advanced Materials ResearchZhongyuan University of TechnologyZhengzhou 450007HenanPeople’s Republic of China International Laboratory for Quantum Functional Materials of Henan&School of Physics and Engineering Zhengzhou UniversityZhengzhou 450001HenanPeople’s Republic of China

The construction of heterojunctions in composite materials to optimize the electronic structures and active sites of energy materials is considered to be the promising strategy for the fabrication of high-performance electrochemical energy *** this paper,a one-step,easy processing and cost-effective technique for generating composite materials with heterojunctions was successfully *** composite containing Ni_(3)S_(4),NiS,and N-doped amorphous carbon(abbreviated as Ni_(3)S_(4)/NiS/NC)with multiple heterojunction nanosheets are synthesized via the space-confined effect of molten salt interface of recrystallized *** lattice matching forms of Ni_(3)S_(4)with cubic structure and NiS with hexagonal structure are confirmed by the detailed characterization of heterogeneous *** C–S bonds are the key factor in realizing the chemical coupling between nickel sulfide and NC and constructing the stable *** functional theory calculations further revealed that the electronic interaction on the heterogeneous interface of Ni_(3)S_(4)/NiS can contribute to high electronic *** heterogeneous interfaces are identified to be the good electroactive region with excellent electrochemical *** synergistic effect of abundant active sites,the enhanced kinetic process and valid interface charge transfer channels of Ni_(3)S_(4)/NiS/NC multiple heterojunction can guarantee high reversible redox activity and high structural stability,resulting in both high specific capacitance and energy/power densities when it is used as the electrode for *** work offers a new avenue for the rational design of the heterojunction materials with improved electrochemical performance through space-confined effect of NaCl.

关键词： multiple heterojunction space-confined effect electronic interaction supercapacitors

CCT Curves of Low-Carbon Mn-Si Steels and Development of Water-Cooled Bainitic Steels

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Journal of Iron and Steel Research International 2010年第3期17卷 46-50页

作者： XU Feng-yun WANG Yong-wei BAI Bing-zhe fang Hong-sheng Key Laboratory for Advanced Materials of Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

CCT curves of Mn-Si steels with different manganese contents or carbon contents were determined. The results show that the transformation range of bainite can be separated from that of ferrite when the manganese content approaches a certain content, and the incubation period of ferrite increases more significantly than that of bainite transformation with the increase of carbon content in Mn-Si steels. Furthermore, water-cooled bainitic steels without adding expensive alloying element were developed. Granular bainite was obtained when a bar with diameter of 300 mm was cooled by water, and a mixed microstructure of granular bainite and martensite was obtained in watercooled plate with thickness of 40 mm. The developed water-cooled bainitic Steels containing no expensive alloying element showed a good combination of strength and toughness. The tensile strength, yield strength, and toughness （AKU at --20℃ ） of bar with diameter of 300 mm after water cooling were higher than 850 MPa, 620 MPa, and 65 J, respectively, and those of plate with thickness of 40mm after water cooling were higher than 1000 MPa, 800 MPa, and 50J, respectively.

关键词： bainitic steel water cooling granular bainite CCT curve Mn-Si steel

Debris flow runout behaviors considering the influences of densely populated buildings

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Journal of Mountain Science 2024年第8期21卷 2696-2712页

作者： ZHANG Shuai fang zhe DAI Cong WANG Shuairong PENG Jingyu ZHOU Yiling SHEN Ping MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou 310058China State Key Laboratory of Internet of Things for Smart City and Department of Ocean Science and Technology University of MacaoMacao SAR 999078China

Debris flows pose serious risks to communities in mountainous areas,often resulting in large losses of human life and *** impeding presence of urban buildings often affects the runout behavior and deposition of debris *** the impact of different building densities and sizes on debris flow dynamics has yet to be quantified to guide urban planning in debris flow risk *** study focused on a debris flow that occurred in Zhouqu County,Gansu Province,China on August 7th,2010,which was catastrophic and destroyed many *** FLO-2D software was used to simulate this debris flow in two scenarios,*** presence and the absence of buildings,to obtain debris-flow intensity *** developed model was then used to further analyze the influence of large buildings and narrow channels within the urban *** simulation results show that considering the presence of buildings in the simulation is essential for accurate assessment of debris flow intensity and deposition *** layout of buildings in the upstream urban area,such as large buildings or parallel buildings which form narrow channels,can affect the flow velocity and depth of debris flow heading towards downstream *** mitigate damage to downstream buildings,the relative spacing(d/a)between upstream and downstream buildings should not exceed a value of two and should ideally be even *** findings provide valuable insights for improving the resistance of mountainous cities to urban debris flows.

关键词： Debris flow Risk Building blockage effect Zhouqu Urban layout

A tectonic geodesy mapping software based on QGIS

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Geodesy and Geodynamics 2020年第1期11卷 31-39页

作者： zhe fang Guoyan Jiang Caijun Xu Shuai Wang School of Geodesy and Geomatics Wuhan UniversityWuhan430079China Earth System Science Programme Faculty of ScienceThe Chinese University of Hong KongHong KongChina Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan430079China Key Laboratory of Geophysical Geodesy Ministry of Natural ResourcesWuhan430079China

To overcome the high cost of learning,non-visual operation,and cumbersome steps of fine-tuning map elements in Generic Mapping Tools(GMT)and other geoscience mapping softwares,we present the Tectonic Geodesy Application(TGA),a user-friendly 64-bit tectonic geodesy mapping software based on the secondary development interface of the open source geographic information system *** this paper,we detailly introduce the architecture and function modules of our software,and highlight the functions of rendering and map decoration through four cases:the geologic map of Papua New Guinea,the seismicity in China and surrounding regions,the seismicity and crustal deformation of the Tibetan Plateau and the coseismic deformation of the 2017 Jiuzhaigou earthquake in *** with GMT,the tectonic geodesy mapping software we developed has the advantages of simple operation,low learning cost and user-friendly interface.

关键词： QGIS Tectonic geodesy Interactive mapping system

Influence of Nb on Microstructure and Property of Low-Carbon Mn-Series Air-Cooled Bainitic Steel

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Journal of Iron and Steel Research International 2010年第1期17卷 49-53页

作者： WANG Yong-wei FENG Chun XU Feng-yun BAI Bing-zhe fang Hong-sheng Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

The effect of Nb on the microstructure evolution of low-carbon Mn-series air cooled bainitic steels has been studied by using thermomeehanical simulation machine, SEM, and TEM observation. The results show that the amount of ferrites is relatively higher in the steel without Nb than that of Nb-bearing steel under same deformation conditions, and the ferrites in Nb-bearing steel are more finer. The mechanical properties of the Nb-bearing steel are higher than those of the steel without Nb at the same finishing rolling temperature （FRT）, and the toughness of the Nb- bearing steel is about 100J higher than that of the steel without Nh at the finishing rolling temperature 750℃. The toughness of Nb microalloyed steel will be improved more effectively than that of the steel without Nb with the decrease of FRT.

关键词： Mn-series bainitic steel grain boundary allotriomorphic ferrite finishing rolling temperature Nb microalloyed steel toughness

A novel three-step approach to separate cathode components for lithium-ion battery recycling

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Rare Metals 2021年第6期40卷 1431-1436页

作者： Yun Zhao Ling-zhe fang Yu-Qiong Kang Li Wang Yu-Nan Zhou Xin-Yi Liu Tao Li Yan-Xi Li zheng Liang zhe-Xu Zhang Bao-Hua Li Engineering Laboratory for Next Generation Power and Energy Storage Batteries Graduate School at ShenzhenTsinghua UniversityShenzhen 518055China Department of Chemistry and Biochemistry Northern Illinois UniversityDekalb 60115USA Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Department of Materials Science and Engineering Stanford UniversityStanford 94305USA

Lithium-ion batteries(LIBs)represent efficient energy storage technology that can help to alleviate fossil fuel-based CO_(2) ***,LIBs are being applied extensively in consumer electronics and electric vehicles,but because of limited resources,there is an urgent need for spent LIB recycling *** complexity of LIBs,especially the electrode part,makes it difficult to achieve precision separations for each single component from the used electrode with low ***,we propose a three-step treatment for the separation of cathode *** detail,detaching of the current collector from the cathode is accomplished by the solvent method,which was found to be an ideal strategy compared with previous ***,a thermal treatment is used to remove the polymer binder in the second step because we demonstrated that it is challenging to separate polyvinylidene fluoride(PVDF)from other cathode components by dissolution with *** separation efficiency between the active material and conductive carbon by the polymer solution in the third step showed reasonably good *** anticipate this work will serve as an important reference for the separation of each single electrode component in both laboratory-and industrialscale *** of binder and development of novel binders,which can be easily recycled for sustainable LIBs,are fruitful areas for further research.

关键词： Lithium-ion batteries Recycling Electrode separation PVDF Thermal treatment Polymer solution

Zn content mediated fibrinogen adsorption on biodegradable Mg-Zn alloys surfaces

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Journal of Magnesium and Alloys 2021年第6期9卷 2145-2154页

作者： Hongyan Wang Mingyun Bai Haonan Yuan Yachen Hou Yihao Liu zhe fang Yufeng Sun Jianfeng Wang Shijie Zhu Shaokang Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou 450002China

The protein adsorption has an immense influence on the biocompatibility of biodegradable Mg *** this work,the effect of Zn content on the fibrinogen(Fg)adsorption behavior in Mg-Zn binary alloy was systematically *** results showed that the Fg adsorption amount increased at first and then decreased with the increase of Zn *** adsorption mechanism was investigated by molecular dynamic and density functional theory *** simulations results showed that Zn with low content existed in the inner layer of Mg alloys due to the lower system energy,which promoted Fg adsorption and the promotion effect was more obvious with the increase of Zn *** Zn content increased to a higher concentration,parts of Zn atoms started to precipitate in the surface,and the Fg-surface interaction energy started to ***,the Zn sites favored the formation of ordered water molecules layers,which inhibit the stable adsorptions of *** inhibition effects of Fg adsorption was enhanced with the Zn content *** short,the simulation results explain the experimental phenomena and reveal the microscopic *** study would provide a significant guidance on the design of biodegradable Mg-Zn alloys.

关键词： Molecular dynamics Protein adsorption Magnesium alloy Zn content DFT simulations

Optical spin-to-orbital angular momentum conversion in structured optical fields

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Chinese Physics B 2020年第6期29卷 436-440页

作者： Yang Zhao Cheng-Xi Yang Jia-Xi Zhu Feng Lin zhe-Yu fang Xing Zhu State Key Laboratory for Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Center for Nanoscale Science and Technology Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China National Center for Nanoscience and Technology Beijing 100190China

We investigate the dynamic quantities:momentum,spin and orbital angular momenta(SAM and OAM),and their conversion relationship in the structured optical fields at subwavelength scales,where the spin–orbit interaction(SOI)plays a key role and determines the behaviors of ***,we examine a nanostructure of a Ag nanoparticle(Ag NP)attached on a cylindrical Ag nanowire(Ag NW)under illumination of elliptically polarized *** dynamic quantities obey the Noether theorem,i.e.,for the Ag nanoparticle with spherical symmetry,the total angular momentum consisting of SAM and OAM conserves;for the Ag NW with translational symmetry,the orbital momentum ***,the spin-to-orbital angular momentum conversion is mediated by SOI arising from the spatial variation of the optical *** this nanostructure,the conservation of momentum imposes a strict restriction on the propagation direction of the surface plasmon polaritons along the Ag ***,the orbital momentum is determined by the polarized properties of the excitation light and the topography of the Ag *** work offers insights to comprehend the light behaviors in the structured optical fields in terms of the dynamic quantities and benefits to the design of optical nano-devices based on interactions between spin and orbital degrees of freedom.

关键词： orbital angular momentum spin angular momentum spin-orbit interaction of light silver nanowire