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Promoting wetting of Mg on the SiC surfaces by addition of Al,Zn and Zr elements:A study via first-principle calculations

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Journal of Magnesium and Alloys 2022年第6期10卷 1663-1671页

作者： weibing Guo wenshan Bian haitao Xue Xiaoming Zhang School of Materials Science and Engineering Hebei University of TechnologyTianjin 300401China State Key Laboratory of Advanced welding and Joining Harbin Institute of TechnologyHarbin 150001China

when preparing SiC/Mg composites,alloy elements play key roles in the nucleation and interfacial *** this paper,effects of Al,Zn and Zr additions on the Mg/SiC interfacial bonding properties were investigated comprehensively via method of first-principle ***(0001)/SiC(0001)interfaces with different terminations and stacking sequences were built and CⅡ-T CⅡtop interface has the largest work of adhesion(w_(ad)).Zn dopants can not improve the w_(ad)for both C-T and Si-T *** atom can only strengthen the C-T *** addition can greatly improve the w_(ad)for both C-T and Si-T interfaces.w_(ad)of C-T interfaces can reach up to 11.55 J/m^(2) and 12.55 J/m^(2) after doping 1 monolayer(ML)of Al and Zr *** w_(ad)can lead to lower contact angles of Mg on SiC surfaces,which can improve wetting and nucleation in SiC/Mg *** of electronic structure shows that Al-C and Zr-C bonds have more covalent composition than the Mg-C bond,which is responsible for the improvement of interfacial bonding *** results in references were also analyzed,which are in well agreement with our calculation results.

关键词： Mg alloy SiC wetting Electronic structure First-principle calculations

Magnetic response to atmospheric heavy metal pollution recorded by dust-loaded leaves in Shougang industrial area, western Beijing

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Chinese Science Bulletin 2008年第10期53卷 1555-1564页

作者： HU ShouYun DUAN XueMei SHEN MingJie U BLAHA w ROESLER YAN haitao E APPEL V HOFFMANN State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sci- ences Nanjing 210008 China Graduate University of Chinese Academy of Sciences Beijing 100049 China epartment of Geography East China Normal University Shanghai 200062 China Institute for Geosciences University of Tubingen 72076 Tubingen Germany epartment of Geography Shanghai Normal-University Shanghai 200234 China

Fifty-five evergreen tree's leaves grow.ng less than one year were collected from Shougang industrial area in western suburb of Beijing, including steel plants and its ambient residential areas, recreational parks and farmlands. Rock magnetic properties and heavy metal contents were studied. The results show that the magnetic properties of leaf samples are predominated by low-coercivity magnetite, and both the concentration and grain size of magnetite particles gradually decreased with the distance from the main pollution source increases. Moreover, there is a significant linear relationship between magnetic parameters (the low-field magnetic susceptibility, saturation isothermal remanent magnetization and anhysteretic remanent magnetization) and heavy metals contents (Fe, Pb, V, Cr and Zn) (0.73≤R≤ 0.88). Hence, the magnetic parameters of leaves can serve as a proxy for quick detecting of the recent atmospheric metallic pollution.

关键词：首钢集团大气重金属污染磁场参数环境保护

Review of fiber superluminescent pulse amplifications

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High Power Laser Science and Engineering 2016年第3期4卷 106-112页

作者： haitao Zhang Xinglai Shen He Hao Qinghua Li Mali Gong Center for Photonics and Electronics State Key Laboratory of Precision Measurement and Instruments Department of Precision Instruments Tsinghua University

High coherence of the laser is indispensable light sources in modern long or short-distance imaging systems, because the high coherence leads to coherent artifacts such as speckle that corrupt image formation. To deliver low coherence pulses in fiber amplifiers, we utilize the superluminescent pulsed light with broad bandwidth, nonlongitudinal mode structure and chaotic mode phase as the seed source of the cascaded fiber amplifiers. The influence of fiber superluminescent pulse amplification(SPA) on the limitations of the performance is analyzed. A review of our research results for SPA in the fibers are present, including the nonlinear theories of this low coherent light sources, i.e., self-focusing(SF), stimulated Raman scattering(SRS) and self-phase modulation(SPM) effects, and the experiment results of the nanosecond pulses with peak power as high as 4.8 Mw and pulse energy as much as 55 mJ. To improve the brightness of SPA light in the future work, we introduce our novel evaluation term and a more reasonable criterion, which is denoted by a new parameter of brightness factor for active large mode area fiber designs. A core-doped active large pitch fiber with a core diameter of 190 μm and a mode-field diameter of 180 μm is designed by this method. The designed fiber allows near diffracted limited beam quality operation, and it can achieve 100 mJ pulse energy and 540 w average power by analyzing the mode coupling effects induced by heat.

关键词： superluminescent pulse amplification fiber amplification incoherent nonlinear effects very large mode field

Computational design of promising 2D electrode materials for Li-ion and Li–S battery applications

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Materials Reports(Energy) 2023年第3期3卷 1-23页

作者： Ke Fan Yuen Hong Tsang haitao Huang Department of Applied Physics and Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHong KongChina

Lithium-ion batteries(LIBs)and lithium-sulfur(Li–S)batteries are two types of energy storage systems with significance in both scientific research and ***,the rational design of electrode materials for overcoming the bottlenecks of LIBs and Li–S batteries(such as low diffusion rates in LIBs and low sulfur utilization in Li–S batteries)remain the greatest challenge,while two-dimensional(2D)electrodes materials provide a solution because of their unique structural and electrochemical *** this article,from the perspective of ab-initio simulations,we review the design of 2D electrode materials for LIBs and Li–S *** first propose the theoretical design principles for 2D electrodes,including stability,electronic properties,capacity,and ion diffusion ***,classified examples of promising 2D electrodes designed by theoretical simulations are given,covering graphene,phosphorene,MXene,transition metal sulfides,and so ***,common challenges and a future perspective are *** review paves the way for rational design of 2D electrode materials for LIBs and Li–S battery applications and may provide a guide for future experiments.

关键词： Lithium-ion batteries Lithium-sulfur batteries 2D electrode materials Computational design

Effect of an antioxidant on the life cycle of wood flour/polypropylene composites

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Journal of Forestry Research 2020年第4期31卷 1435-1443页

作者： Haigang w.ng Jingfa Zhang haitao Fu weihong w.ng Qingwen w.ng Key Laboratory of Bio-Based Material Science and Technology(Ministry of Education) Northeast Forestry UniversityHarbin 150040People’s Republic of China College of Materials and Energy South China Agricultural UniversityGuangzhou 510642People’s Republic of China

This study assessed the life cycle of biocomposites with antioxidants by repeated *** effects of antioxidants on the life cycle of wood flour/polypropylene(PP)composites were determined by analyzing their mechanical and thermal *** composites were repeatedly processed for seven times with pelletizing and *** antioxidant,pentaerythritoltetrakys 3-(3,5-ditert-butyl-4-hydroxyphenyl)propionate,was *** mechanical strength of the biocomposites decreased after *** transformed infrared analysis showed that thermo-oxidative aging occurred during *** thermal performance of the resulting composites decreased because of *** flour/PP has a long lifetime and antioxidants can slow the thermo-oxidative and mechanical degradation during reprocessing.

关键词： wood-plastic composites Polypropylene Reprocessing Antioxidant

Highly bonded T-Nb2O5/rGO nanohybrids for 4 V quasisolid state asymmetric supercapacitors with improved electrochemical performance

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Nano Research 2018年第9期11卷 4673-4685页

作者： Yuzhi Jiao haitao Zhang Hailang Zhang Ao Liu Yanxia Liu Suojiang Zhang Beijing Key Laboratory of Ionic Liquids Clean Process Institute of Process Engineering Chinese Academy of Sciences Beijing I O0190 China School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China Department of Chemical and Material Engineering Hefei University Hefei 230601 China Zhengzhou Key Laboratory of Energy Storage Science and Technology Zhengzhou Institute of Emerging Industrial Technology Zhengzhou 450000 China

Orthorhombic niobium pentoxide （T-Nb2O5）/reduced graphene oxide nanohybrids were fabricated via the hydrothermal attachment of Nb2Os nanowires to dispersed graphene oxide nanosheets followed by a high-temperature phase transformation. Electrochemical measurements showed that the nanohybrid anodes possessed enhanced reversible capacity and superior cycling stability compared to those of a pristine T-Nb205 nanowire electrode. Ow.ng to the strong bonds between graphene nanosheets and T-Nb2O5 nanowires, the nanohybrids achieved an initial capacity of 227 mAh·g^-1. Additionally, non-aqueous asymmetric supercapacitors （ASCs） were fabricated with the synthesized nanohybrids as the anode and activated carbon as the cathode. The 3 V Li-ion ASC with a LiPF6-based organic electrolyte achieved an energy density of 45.1 wh·kg^-1 at 715.2 w·kg^-1. The working potential could be further enhanced to 4 V when a polymer ionogel separator （PVDF-HFP/LiTFSI/EMIMBF4） and formulated ionic liquid electrolyte were employed. Such a quasi-solid state ASC could operate at 60℃ and delivered a maximum energy density of 70 wh·kg^-1 at 1 kw·kg^-1.

关键词： solid-state supercapacitor nanohybrid electrode ionogel polymer electrolyte electrochemicalperformance

A data-driven framework to predict the morphology of interfacial Cu6Sn5 IMC in SAC/Cu system during laser soldering

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Journal of Materials Science & Technology 2020年第15期47卷 115-127页

作者： Anil Kunwar Lili An Jiahui Liu Shengyan Shang Peter Raback haitao Ma Xueguan Song Department of Materials Engineering KU LeuvenKasteelpark Arenberg 44B-3001 LeuvenBelgium School of Mechanical Engineering Dalian University of TechnologyDalian 116024China School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China CSC-IT Center for Science Keilaranta 14P.O.Box 405FIN-02101 EspooFinland

A data-driven approach combining together the experimental laser soldering,finite element analysis and machine learning,has been utilized to predict the morphology of interracial intermetallic compound(IMC) in Sn-xAg-yCu/Cu(SAC/Cu) *** types of SAC solders with varying weight proportion of Ag and Cu,have been processed with fiber laser at different magnitudes of power(30-50 w) and scan speed(10-240 mm/min),and the resultant IMC morphologies characterized through scanning electron microscope are categorized as prismatic and scalloped *** the different alloy composition and laser parameters,finite element method(FEM) is employed to compute the transient distribution of temperature at the interface of solder and *** FEM-generated datasets are supplied to a neural network that predicts the IMC morphology through the quantified values of temperature dependent Jackson parameter(αJ).The numerical value of αJ predicted from neural network is validated with experimental IMC *** critical scan speed for the morphology transition between prismatic and scalloped IMC is estimated for each solder composition at a given ***-0.7 Cu having the largest critical scan speed at 30 w and Sn-3.5 Ag alloy having the largest critical scan speed at input power values of 40 w and 50 w,thus possessing the greatest likelihood of forming prismatic interfacial IMC during laser soldering,can be inferred as most suitable SAC solders in applications exposed to shear loads.

关键词： Intermetallic compound Neural network Finite element method(FEM) Laser parameters Lead-free solders Morphology

Scale up and stability test for oxidative coupling of methane over Na_2wO_4-Mn/SiO_2 catalyst in a 200 ml fixed-bed reactor

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Journal of Natural Gas Chemistry 2008年第1期17卷 59-63页

作者： haitao Liu Xiaolai w.ng Dexin Yang Runxiong Gao Zhonglai w.ng Jian Yang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of ScienceLanzhou 730000 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The study of scale up for the oxidative coupling of methane （OCM） has been carried out in a 200 ml stainless steel fixed-bed reactor over a 5wt% Na2wO4-1.9wt% Mn/SiO2 （w-Mn/SiO2） catalyst. The effects of reaction conditions were investigated in detail. The results showed that, with increasing reaction temperature, the gas-phase reaction was enhanced and a significant amount of methane was converted into COx; with the CH4/O2 molar ratio of 5, the highest C2 （ethylene and ethane） yield of 25% was achieved; the presence of steam （as diluent） had a positive effect on the C2 selectivity and yield. Under lower methane gaseous hourly space velocity （GHSV）, higher selectivity and yield of C2 were obtained as the result of the decrease of released heat energy. In 100 h reaction time, the C2 selectivity of 66%-61% and C2 yield of 24.2%-25.4% were achieved by a single pass without any significant loss in catalytic performance.

关键词： scale up oxidative coupling of methane w-Mn/SiO2 200 ml fixed-bed reactor

High-entropy ferroelastic(10RE_(0.1))TaO_(4) ceramics with oxygen vacancies and improved thermophysical properties

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Journal of Materials Science & Technology 2023年第26期157卷 98-106页

作者： Jun w.ng Xiaoyu Chong Liang Lv Yuncheng w.ng Xiaolan Ji haitao Yun Jing Feng Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093China AECC South Industry Co. Ltd.Zhuzhou 412000China

The primary purpose of this work is to optimize the thermophysical properties of rare-earth tan-talate ceramics using the high-entropy ***,the high-entropy rare-earth tantalate ceramic(Y_(0.1)Nd_(0.1)Sm_(0.1)Gd_(0.1)Dy_(0.1)Ho_(0.1)Er_(0.1)Tm_(0.1)Yb_(0.1)Lu_(0.1))TaO_(4)((10RE_(0.1))TaO_(4))is synthesized *** lat-tice distortion and oxygen vacancy concentration are characterized firstly in the rare-earth ***,compared with single rare-earth tantalates,the thermal conductivity of(10RE_(0.1))TaO_(4) is reduced by 16%-45%at 100℃ and 22%-45%at 800℃,and it also presents lower phonon thermal conductivity in the entire temperature range from 100 to 1200℃.The phonon thermal conductivity(1.0-2.2 w m^(-1) K^(-1),100-1200℃)of(10RE_(0.1))TaO_(4) is lower than that of the currently reported high-entropy four-,five-and six-component rare-earth *** is the result of scattering by the ferroelastic domain,lattice distortion associated with size and mass disorder,and point defects,which target low-,mid-and high-frequency ***,(10RE_(0.1))TaO_(4),as an improved candidate for thermal barrier coatings materials(TBCs),has a higher thermal expansion coefficient(10.5×10^(-6)K^(-1) at 1400℃),lower Young’s modulus(123 GPa)and better high-temperature phase stability than that of single rare-earth tantalates.

关键词： High-entropy rare-earth tantalate ceramic Ferroelastic domain Lattice distortion Oxygen vacancy Thermal conductivity Thermal barrier coatings materials