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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 9-15页

作者：蒋大鹏 ZHU Xiaomin YU Jiakang State key laboratory of Solidification processing Northwestern Polytechnical UniversityXi’an 710072China Xi’an Microelectronic Technology Institute Xi’an 710072China

The effect of graphite surface modification on the thermal conductivity(TC) and bending strength of graphite flakes/Al composites(Gf/Al) prepared by gas pressure infiltration were investigated. Al3 Ni and Al4C3 phase may form at the interface in Ni-coated Gf/Al and uncoated Gf/Al composites, respectively, while the Al-Cu compound cannot be observed in Cu-coated Gf/Al composites. The Cu and Ni coatings enhance TC and the bending strength of the composites in the meantime. TC of Cu-coated Gf/Al composites reach 515 Wm^-1·K^-1 with 75 vol% Gf, which are higher than that of Ni-coated Gf/Al. Meanwhile, due to Al3 Ni at the interface, the bending strength of Ni-coated Gf/Al composites are far more than those of the uncoated and Cu-coated Gf/Al with the same content of Gf. The results indicate that metal-coated Gf can effectively improve the interfacial bonding between Gf and Al.

关键词： graphite flakes/Al composites metal coating thermal conductivity bending strength

Tuning active sites in MoS_(2)-based catalysts via H_(2)O_(2)etching to enhance hydrodesulfurization performance

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Petroleum Science 2023年第6期20卷 3875-3886页

作者： Shui-Sen He Ting-Ting Huang Chao Chen Yu Fan State key laboratory of Heavy Oil processing China University of PetroleumBeijing102249China State key laboratory Base for Eco-Chemical Engineering in College of Chemical Engineering Qingdao University of Science and TechnologyZhengzhou Road 53Qingdao266042ShandongChina

A H_(2)O_(2)etching strategy was adopted to introduce coordinatively unsaturated sites(CUS)on MoS_(2)-based catalysts for dibenzothiophene(DBT)hydrodesulfurization(HDS).The CUS concentrations on MoS_(2) slabs were finely regulated by changing the concentrations of H_(2)O_(2)*** the increasing H_(2)O_(2)concentrations(0.1–0.3 mol/L),The CUS concentrations on MoS_(2) slabs increased ***,the high-concentration H_(2)O_(2)etching(0.5 mol/L)increased the MoOxSy and MoO_(3) contents on MoS_(2) slabs compared to etching with the H_(2)O_(2)concentration of 0.3 mol/L,which led to the less CUS concentration in the sulfided Mo–H-0.5 catalyst than in the sulfided Mo–H-0.3 catalyst.A microstructure-activity correlation indicated that the CUS introduced by H_(2)O_(2)etching on MoS_(2) slabs significantly enhanced DBT *** Co loadings were further introduced into Mo–H-0.3,which had the most CUS concentration,and the corresponding 0.2-CoMo catalyst with the highest CoMoS content(3.853 wt%)exhibited the highest reaction rate constant of 6.95×10^(−6)mol g^(−1)s^(−1)among these CoMo catalysts.

关键词： H_(2)O_(2)etching Coordinatively unsaturated site concentrations CoMoS Hydrodesulfurization

Effect of dimensionless heat input during laser solid forming of high-strength steel

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Journal of Materials Science & Technology 2022年第4期99卷 127-137页

作者： Chunping Huang Renyu Liang Fenggang Liu Haiou Yang Xin Lin National Defense key Discipline laboratory of Light Alloy processing Science and Technology Nanchang Hangkong UniversityNanchang 330063China key laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’an 710072China

Laser solid forming(LSF)technology can be used to rapidly manufacture and repair high-strength steel parts with superior performance,but the value of the heat input during operation is difficult to quantify,which has a substantial impact on the microstructure and mechanical properties of the parts.A promising method to improve the forming efficiency and quality of LSFed parts is to accurately control the heat input and explore its relationship with the microstructure and mechanical *** remove the interference of other variables from the experiment,the dimensionless heat input Q;^(∗)was *** Q^(∗)values were designed in advance to calculate the experimental parameters used to perform the LSF *** microstructure was observed at different regions of the sample,and its mechanical properties were *** the results,the following conclusions were *** Q;^(∗)value was directly related to the cooling rate and heat accumulation in the top structure,leading to the formation of different microstructures;it also modified the original structure at the bottom,affecting the subsequent thermal cycle and indirectly changing the tempered martensite *** heat input also affected the mechanical properties of the *** hardness of the stable zone decreased with increasing Q;^(∗)value,and the lowest value was 190 ***,the tensile strength and yield strength of the LSFed samples decreased considerably with increasing Q;^(∗)value,and the lowest values were 735 and 604 MPa,*** the elongation and reduction in the area increased after a slight *** Q;^(∗)value had a significant effect on heat *** Q;^(∗)=2.9,the increase in tensile strength and yield strength after heat treatment was the largest(29%and 44%,respectively).

关键词： Dimensionless heat input Laser solid forming High-strength steel Microstructure Mechanical property

A Cascaded Co-evolutionary Model for Attribute Reduction and Classification Based on Coordinating Architecture with Bidirectional Elitist Optimization

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Chinese Journal of Electronics 2017年第1期26卷 13-21页

作者： DING Weiping WANG Jiandong LI Yuehua CHENG Xueyun School of Computer Science and Technology Nantong University key laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Provincial key laboratory for Computer Information processing Technology Soochow University College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics

A cascaded co-evolutionary model for Attribute reduction and classification based on Coordinating architecture with bidirectional elitist optimization(ARC-CABEO) is proposed for the more practical applications. The regrouping and merging coordinating strategy of ordinary-elitist-role-based population is introduced to represent a more holistic cooperative co-evolutionary framework of different populations for attribute reduction. The master-slave-elitist-based subpopulations are constructed to coordinate the behaviors of different elitists, and meanwhile the elitist optimization vector with the strongest balancing between exploration and exploitation is selected out to expedite the bidirectional attribute co-evolutionary reduction process. In addition, two coupled coordinating architectures and the elitist optimization vector are tightly cascaded to perform the co-evolutionary classification of reduction subsets. Hence the preferring classification optimization goal can be achieved better. Some experimental results verify that the proposed ARC-CABEO model has the better feasibility and more superior classification accuracy on different UCI datasets, compared with representative algorithms.

关键词： Attribute reduction for classification Bidirectional elitist optimization Coordinating architecture Cascaded co-evolutionary model

On-site building of a Zn^(2+)-conductive interfacial layer via short-circuit energization for stable Zn anode

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Science Bulletin 2021年第6期66卷 545-552,M0003页

作者： Ping Xiao Lanlan Xue Yanpeng Guo Lintong Hu Can Cui Huiqiao Li Tianyou Zhai State key laboratory of Materials processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China key laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Aqueous zinc ion batteries(ZIBs)show great potential in large-scale energy storage systems for their advantages of high safety,low cost,high capacity,and environmental ***,the poor performance of Zn metal anode seriously hinders the application of ***,we use the zinc-ion intercalatable V_(2)O_(5)nH_(2)O(VO)as the interface modification material,for the first time,to on-site build a Zn^(2+)-conductive ZnxV_(2)O_(5)nH_(2)O(ZnVO)interfacial layer via the spontaneous short-circuit reaction between the pre-fabricated VO film and Zn metal *** with the bare Zn,the ZnVO-coated Zn anode exhibits better electrochemical performances with dendrite-free Zn deposits,lower polarization,higher coulombic efficiency over 99%after long cycles and 10 times higher cycle life,which is confirmed by constructing Zn symmetrical cell and Zn|ZnSO_(4)+Li_(2)SO_(4)|LiFePO_(4) full cell.

关键词： V_(2)O_(5) Interfacial layer On-site building Zn anode Zinc ion batteries

A Miniaturized Bandwidth Reconfigurable Bandpass Chip Filter with Semi-lumped Topology and GaAs pHEMT Technology

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Chinese Journal of Electronics 2021年第1期30卷 192-198页

作者： LI Linqing ZHU Haoran NING Xingyu LI Zunwen WU Xianliang key Lab of Intelligent Computing and Signal processing Ministry of Education Anhui University

A miniaturized reconfigurable bandpass chip filter with semi-lumped topology and Gallium Arsenide pseudomorphic High electron mobility transistor（GaAs pHEMT） technology is proposed. Semi-lumped topology is employed to instead the traditional lumped inductor with microstrip transmission line, which can reduced the size of the tunable filter significantly. Three-order series and shunt resonated bandpass filter is implemented with shorted stubs and metal-insulator-metal capacitors. Two transmission zeros are introduced with the series resonator and the shunted GaAs FET. By tuning the gate bias circuit of the FET, the capacitance of the series resonator is changed and the bandwidth of the filter is adjusted correspondingly. An equivalent circuit model is developed to interpret the mechanism of the proposed filter circuit. A reconfigurable on chip filter sample operated at 10 GHz is fabricated to validate the design. Two fractional bandwidth of 14.3% and 23.5% are tuned with bias voltage of the FET, while insertion loss of 2.4 d B and 2.2 d B are observed with the filter, respectively. The area of the chip filter is 0.86 × 0.96 mm2and is equivalent to an electrical length of 0.08 × 0.09λg2at center frequency. Measurement results agree well with the simulation ones.

关键词： Passive filters and other passive networks Waveguide and microwave transmission line components Semiconductor integrated circuit design, layout, modelling and testing Other field effect integrated circuits Bandwidth reconfigurable GaAs process Miniaturized On-chip filter Semi-lumped topology

Self-supported Fe_(x)Ni_(1-x)MoO_(4) with synergistic morphology and composition for efficient overall water splitting at large current density

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Chinese Chemical Letters 2023年第2期34卷 327-332页

作者： Xin-Yu Zhang Wen-Li Yu Jie Zhao Jia-Yu Fu Bin Dong Fu-Li Wang Jian-Feng Yu Chen-Guang Liu Yong-Ming Chai State key laboratory of Heavy Oil processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Developing the high activity,low cost and robust large-current-density-based electrocatalysts is of great significance for the industrial electrolytic water ***,the current range of most reported materials is small,which makes it difficult for them to play their roles in practical ***,a self-supported amorphous FexNi1-xMo O4/IF treated with ammonium fluoride (AF_(0.1)-FNMO/IF) is synthesized by one-step hydrothermal *** the help of NH4F,AF_(0.1)-FNMO/IF exhibits a vertically cross-linked nanosheet with spherical *** measurement shows that AF_(0.1)-FNMO/IF affords a large current density ordeal and only need low overpotentials of 289 and 345 m V to reach a current response of 500 m A/cm ^(2)for oxygen evolution reaction and hydrogen evolution reaction,respectively,together with long-time stability (both at 500,1000 and 2000 m A/cm ^(2)) in 1.0 mol/L KOH *** it as bifunctional catalyst for overall water splitting,the current densities of 100,500,1000 and1500 m A/cm ^(2)are achieved at a cell voltage of 1.71,1.88,1.94 and 1.97 V with excellent durability,which is much better than that of most published *** work provides valuable insight for designing higher activity nickel iron-based molybdate catalysts with large current density.

关键词： Bimetallic molybdate Bifunctional electrocatalysts Overall water splitting Large current density Alkaline solution

Rheological investigations of the improved fine scheelite flotation spiked with agitation medium

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International Journal of Mining Science and Technology 2022年第6期32卷 1379-1388页

作者： Wei Chen Guofan Zhang Yangge Zhu College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China State key laboratory of Mineral processing BGRIMM Technology GroupBeijing 100160China School of Mineral processing and Bioengineering Central South UniversityChangsha 410083China

The fine scheelite flotation using garnet and glass beads as agitation medium was investigated through slurry rheology and froth property analysis. The apparent viscosity of fine scheelite, calcite and quartz(-20 μm) slurry were measured and the corresponding scheelite flotation behaviours, froth water recovery and froth height were studied. It was found that calcite slurry could aggregate into network structures and exhibit much higher apparent viscosity at the vicinity of pH 8.5–9.0 than scheelite and quartz(scheelite, calcite, and quartz slurry at 20.34, 38.66, and 14.58 mPa·s, respectively). Agitation medium containing garnet and glass beads could reduce the slurry apparent viscosity by effectively dispersing the calcite network structures in flotation slurry, and improve the fine scheelite flotation selectivity. As the apparent viscosity was reduced, the froth water recovery decreased from 24.33% to 6.37% and initial froth height of the flotation froth decreased from 69.6 to 8.7 mm, and finally results in increase in separation efficiency from 23.10% to 31.96%. The results could be potentially used in flotation of fine minerals by applying agitation medium to improve the process selectivity.

关键词： Rheology Flotation Fine scheelite Agitation medium

Electrodeposition of Pt-Decorated Ni(OH)_(2)/CeO_(2) Hybrid as Superior Bifunctional Electrocatalyst for Water Splitting

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Research 2020年第1期2020卷 1698-1708页

作者： Huanhuan Liu Zhenhua Yan Xiang Chen Jinhan Li Le Zhang Fangming Liu Guilan Fan Fangyi Cheng key laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071China

The facile synthesis of highly active and stable bifunctional electrocatalysts to catalyze water splitting is attractive but ***,we report the electrodeposition of Pt-decorated Ni(OH)_(2)/CeO_(2)(PNC)hybrid as an efficient and robust bifunctional *** graphite-supported PNC catalyst delivers superior hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)activities over the benchmark Pt/C and RuO_(2),*** overall water electrolysis,the PNC hybrid only requires a cell voltage of 1.45V at 10mAcm-2 and sustains over 85 h at 1000mAcm^(-2).The remarkable HER/OER performances are attributed to the superhydrophilicity and multiple effects of PNC,in which Ni(OH)_(2)and CeO_(2)accelerate HER on Pt due to promoted water dissociation and strong electronic interaction,while the electron-pulling Ce cations facilitate the generation of high-valence Ni OER-active *** results suggest the promising application of PNC for H2 production from water electrolysis.

关键词： catalyst attributed attractive

Electron transport in dye-sensitized solar cells based on TiO_2 nanowires

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Science China(Physics,Mechanics & Astronomy) 2014年第5期57卷 892-897页

作者： JIAO XingJian WANG Xiao LI Xin CHEN HuiYuan WANG Gang LI JianBao LIN Hong State key laboratory of New Ceramics and Fine processing Department of Materials Science and EngineeringTsinghua University College of Chemical Engineering Qinghai University

Anatase titanium dioxide nanowire arrays were prepared by hydrothermally oxidizing titanium foils in aqueous alkali and transferred onto fluorinated tin oxide(FTO)glass for use as the photoanodes of front side illuminated dye-sensitized solar cells(DSCs).Electrochemical impedance spectroscopy(EIS)measurement was applied to compare the electron transport and recombination properties of DSCs using TiO2nanowire films and TiO2nanoparticle films as *** was found that the nanowire array films possess smaller electron transport resistance(Rt)and larger electron diffusion length(Le)in the photoanodes,suggesting that the nanowire arrays can enhance the electron transport rate and have a potential to improve the charge collection efficiency of DSCs.

关键词： TiO2 nanowires dye-sensitized solar cells electrochemical impedance spectroscopy electron transport