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Light(Science & Applications) 2020年第1期9卷 1170-1178页

作者： Chang Hu xianjie wang Bo Song Department of Physics Harbin Institute of Technology150001 HarbinChina National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology150001 HarbinChina

Two-dimensional(2D)materials such as graphene and transition-metal chalcogenides have been extensively studied because of their superior electronic and optical ***,2D materials have shown great practical application in position-sensitive detectors(PSDs),originating from the lateral photoelectrical effect of the materials or *** high position sensitivity and ultrafast photoresponse of PSDs based on 2D materials,especially compatibility with Si technology,may enable diverse optoelectronic *** this review,recent studies of PSDs based on 2D materials are summarized,providing a promising route for high-performance PSDs.

关键词： optoelectronic performance effect

COMPUTER PROGRAM FOR DIRECTED STRUCTURE TOPOLOGY OPTIMIZATION

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Acta Mechanica Solida Sinica 2015年第4期28卷 431-440页

作者： xianjie wang Xun'an Zhang Kepeng Cheng School of Urban Construction and Management Yunnan University School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University

To compensate for the imperfection of traditional bi-directional evolutionary structural optimization, material interpolation scheme and sensitivity filter functions are introduced. A suitable filter can overcome the checkerboard and mesh-dependency. And the historical information on accurate elemental sensitivity numbers are used to keep the objective function converging steadily. Apart from rational intervals of the relevant important parameters, the concept of distinguishing between active and non-active elements design is proposed, which can be widely used for improving the function and artistry of structures directly, especially for a one whose accurate size is not given. Furthermore, user-friendly software packages are developed to enhance its accessibility for practicing engineers and architects. And to reduce the time cost for large timeconsuming complex structure optimization, parallel computing is built-in in the MATLAB codes. The program is easy to use for engineers who may not be familiar with either FEA or structure optimization. And developers can make a deep research on the algorithm by changing the MATLAB codes. Several classical examples are given to show that the improved BESO method is superior for its handy and utility computer program software.

关键词： bi-directional evolutionary structural optimization (BESO) continuum structurescomputer program development improved algorithm directed structure topology optimizationportion construction design

Concurrent Analysis and Design of Structure and Its Periodic Material

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Acta Mechanica Solida Sinica 2016年第6期29卷 663-674页

作者： xianjie wang Yun qin Xun'an Zhang School of Urban Construction and Management Yunnan University Kunming 650091 China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710129 China

The specific good properties of cellular materials and composite materials, such as low density and high permeability, make the optimal design of such materials necessary and at- tractive. However, the given materials for the structures may not be optimal or suitable, since the boundary condition and applied loads vary in practical applications; hence the macro-structure and its material micro-structure should be considered simultaneously. Although abundant studies have been reported on the structural and material optimization at each level, very few of them considered the mutual coordination on both scales. In this paper, two FE models are built for the macro-structure and the micro-structure, respectively; and the effective elastic properties of the periodic micro-structure are blended into the analysis of macro-structure by the homogenization theory. Here, a topological optimum is obtained by gradually re-distributing the constituents within the micro-structure and updating the topological shape at the macro-structure until converges are achieved on both scales. The mutual coordination between the roles of micro-scale and macro-scale is considered. Some numerical examples are presented, which illustrate that the proposed optimization algorithm is effective and highly efficient for the micro-structure design and macro-structure optimization. For the composite design, one can see reasonable effects of the stiffness of base materials on the resultant topologies.

关键词： multi-scale homogenization method concurrent optimization periodic cellularmaterial periodic composite material

Highly active copper-intercalated weakly crystallized δ-MnO_(2) for low-temperature oxidation of CO in dry and humid air

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 127-136页

作者： Hao Zhang Huinan Li Pengyi Zhang Tingxia Hu xianjie wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Beijing Key Laboratory for Indoor Air Quality Evaluation and Control Beijing100084China Midea Corporate Research Center Foshan528311China

Copper intercalated birnessite MnO_(2)(δ-MnO_(2))with weak crystallinity and high specific surface area(421 m^(2)/g)was synthesized by a one-pot redox method and investigated for low-temperature CO *** molar ratio of Cu/Mn was as high as 0.37,which greatly weakened the Mn-O bond and created a lot of low-temperature active oxygen *** situ DRIFTS revealed strong bonding of copper ions with ***-synthesized MnO_(2)-150Cu achieved 100%conversion of 250 ppm CO in normal air(3.1 ppm H_(2)O)even at−10°C under the weight-hourly space velocity(WHSV)of 150 L/(g·h).In addition,it showed high oxygen storage capacity to oxidize CO in inert *** the concurrent moisture in air significantly inhibited CO adsorption and its conversion at ambient temperature,MnO_(2)-150Cu could stably convert CO in 1.3%moisture air at 70°C owing to its great low-temperature activity and reduced competitive adsorption of water with increased *** study discovers the excellent low-temperature activity of weakly crystallized δ-MnO_(2) induced by high content intercalated copper ions.

关键词： CO oxidation Birnessite Interlayer copper Low-temperature Oxygen storage capacity

HMTA-assisted One-pot Synthesis of Greigite Nano-platelet and Its Magnetic Properties

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Journal of Materials Science & Technology 2015年第9期31卷 895-900页

作者： Tuoquan Liao Wei wang Yongli Song xianjie wang Yanqiang Yang Xiaoyang Liu Academy of Fundamental and Interdisciplinary Sciences Harbin Institute of Technology Department of Physics Harbin Institute of Technology State Key Lab of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University

A facile one-pot hydrothermal procedure for the synthesis of magnetic greigite was investigated in this work, by using FeSO4, thioacetamide, and a tiny amount of hexamethylenetetramine （HMTA） as starting materials. The HMTA molecule, which acted as a chelating agent and an oxidant, could not only tune the valence fluctuation of iron ions, but also direct the hydrothermal reaction towards the exclusive for- mation of greigite platelets with hundreds of nanometers in lateral size. In the presence of a static magnetic field during this synthesis, the greigite nano-platelets were apt to congregate to form 3D flower-like microspheres. A set of experiments suggested that the ferrous ions were at first partly oxidized by HMTA to form ferric intermediates, i.e., Fe（OH）3 and Fe2O3. Then excessive ferrous ions, along with the solid in- termediates, reacted with sulfide ions, and finally evolved into greigite, Taken into consideration that a similar process occurred in magnetotactic bacteria, our results may give a hint at the design of biomimetic synthesis strategies to produce nanomaterials, especially the magnetosome-like greigite.

关键词： GreigiteNano-plateletHydrothermal synthesisMagnetic materials

Strong room-temperature emission from defect states in CVD-grown WSe2 nanosheets

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Nano Research 2018年第7期11卷 3922-3930页

作者： Shudong Zhao Lei Tao Peng Miao xianjie wang Zhiguo Liu Yi wang Bingsheng Li Yu Sui Yang wang Department of Physics Harbin Institute of Technology Harbin 150001 China School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001 China Academy of Fundamental ond lnterdisciplinary Sciences Harbin Institute of Technology Harbin 150001 China

Monolayer transition metal dichalcogenides （TMDCs）, as direct bandgap semiconductors, show promise for applications in ultra-thin flexible optoelec- tronic devices. However, the optical properties and device performance are greatly affected by defects, such as vacancies, present in these materials. Vacancies exist unavoidably in mechanically exfoliated or grown by chemical vapor deposition （CVD） monolayer TMDCs; therefore, their influence on the electric and optical properties of host materials has been widely studied. Here, we report a new defect state located at 1.54 eV, which is 70 meV lower than the neutral exciton energy in as-prepared WSe2 monolayers grown by CVD. This defect state is clearly observed in photoluminescence （PL） and Raman spectra at ambient conditions. PL mapping, Rarnan mapping, and atomic force microscopy analysis indicate a solid-vapor reaction growth mechanism of the defect state formation. During a certain growth stage, nuclei with the composition of WOxSey do not fully react with the Se vapor, leading to the defect formation. This type of defects permits radiative recombination of bound neutral excitons, which can make the PL intensity as strong as the intrinsic excitation. Our findings reveal a new way to tailor the optical properties of two-dimensional TMDCs without any additional processes performed after growth.

关键词： monolayer WSe2 defects photoluminescence chemical vapordeposition (CVD) growth mechanism

Ion association tailoring SEI composition for Li metal anode protection

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Journal of Energy Chemistry 2020年第6期29卷 1-6,I0001页

作者： Yitao He Yaohui Zhang Peng Yu Fei Ding Xifei Li Zhihong wang Zhe Lv xianjie wang Zhiguo Liu Xiqiang Huang School of Physics Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Beijing Aerospace Technology Institute The Third Academy of CASCBeijing 100074China Science and Technology on Power Sources Laboratory Tianjin Institute of Power SourcesTianjin 300384China Institute of Advanced Electrochemical Energy Xi’an University of TechnologyXi’an 710048ShaanxiChina Center for International Cooperation on Designer Low-carbon&Environmental Materials(CDLCEM) Zhengzhou UniversityZhengzhou 450001HenanChina

Electrolyte additives play an important role in suppressing lithium dendrites through tailoring the composition/property of the SEI,however lacking of additives can achieve high performances both in ether and carbonate electrolytes hinders further enhancement of the high voltage lithium^-metal ***,lithium perchlorate(LiClO4)has been presented as an excellent additive to meet the above *** optimized chemical composition of SEI can be achieved through the formation of ionic *** results indicate that the LiClO4 behaves like a catalyst,which promotes LiTFSI to form a better SEI to inhibit further *** coulombic efficiencies and cycling performances were obtained both in ether and carbonate *** study paves a new pathway for designing bi-soluble additives for safe lithium metal batteries.

关键词： Ion association Lithium metal Electrolyte additive

Magnetic field‐enhanced water splitting enabled by bifunctional molybdenum‐doped nickel sulfide on nickel foam

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Carbon Energy 2023年第10期5卷 50-63页

作者： Yuanyuan Zhang Mengxin Chen Ping Guo Yunchen Du Bo Song xianjie wang Zaixing Jiang Ping Xu MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbinChina School of Physics Harbin Institute of TechnologyHarbinChina

Herein,we report bifunctional molybdenum-doped nickel sulfide on nickel foam(Mo-NiS_(x)/NF)for magnetic field-enhanced overall water splitting under alkaline *** doping of Mo can lead to optimization of the electronic structure of NiS_(x),which accelerates the dissociation of H2O and the adsorption of OH−in the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)processes,*** addition,the magnetically active Mo-NiS_(x)/NF can further enhance the HER and OER activity under an applied magnetic field due to the magnetoresistance effect and the ferromagnetic(FM)exchange-field penetration *** a result,Mo-NiS_(x)/NF requires low overpotentials of 307 mV at 50mA cm^(−2)(for OER)and 136 mV at 10mA cm^(−2)(for HER)under a magnetic field of 10000 ***,the electrolytic cell constructed by the bifunctional Mo-NiS_(x)/NFs as both the cathode and the anode shows a low cell voltage of 1.594 V at 10 mA cm^(−2)with optimal stability over 60 h under the magnetic *** enhancement of the HER and OER processes by an external magnetic field through rational design of electrocatalysts might be promising for overall water splitting applications.

关键词： electron density modulation FM exchange‐field penetration effect magnetic field magnetoresistance effect water splitting

Motivation——A Factor Affecting Foreign Language Learning

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河南教育学院学报（哲学社会科学版） 1999年第1期18卷 75-77页

作者： wang xianjie

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Ⅰ．ＴｙｐｅｓｏｆＭｏｔｉｖａｔｉｏｎＭｏｔｉｖａｔｉｏｎｉｓａｒａｔｈｅｒｉｎｔｅｒｎａｌｄｒｉｖｅａｎｄｅｍｏｔｉｏｎａｌｅｆｅｃｔｔｈａｔｅｎｃｏｕｒａｇｅｓｐｅｏｐｌｅｔｏｐｕｒｓｕｅａｃｏｕｒｓｅｏｆａｃｔｉｏｎ．Ｍｏｔｉｖａｔｉｏｎｉｓｗ...

关键词： motivation factor foreign language Learning achievement

Large photovoltaic effect with ultrahigh open-circuit voltage in relaxor-based ferroelectric Pb(In_(1/2)Nb_(1/2))O_(3)-Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)ceramics

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Journal of Materials Science & Technology 2022年第9期104卷 119-126页

作者： Xudong Qi Kai Li Enwei Sun Bingqian Song Da Huo Jiaming Li xianjie wang Rui Zhang Bin Yang Wenwu Cao Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of Physics Harbin Institute of TechnologyHarbin 150001China Department of Mathematics and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

Recently,the anomalous photovoltaic effect of ferroelectric materials has attracted considerable attention in the construction of efficient solar cells owing to the above-bandgap photovoltage of these *** this study,we investigate the anomalous photovoltaic effect of relaxor-based ferroelectric Pb(In_(1/2)Nb_(1/2))O_(3)-Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)(PIMN-PT)ceramics with large remnant polarization and a narrow optical *** photovoltaic performance with an ultrahigh open-circuit voltage of 23 V(575 V/cm)is achieved,which is higher than the open-circuit voltages of all reported polycrystalline materials with similar *** phase structure,microstructure morphology,domain structure,ferroelectric and optical characteristics are analyzed,which could provide clues to the origin of the ultrahigh open-circuit voltage of PIMN-PT *** results suggest that the relaxor-based ferroelectric PIMNPT system is a potential candidate for photovoltaic solar energy conversion devices.

关键词： Photovoltaic Ferroelectric PIMN-PT ceramics Open-circuit voltage Domain structure