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Rare Metals 2023年第10期42卷 3420-3429页

作者： Rui sun Zhan-Hua Su Zhi-Feng Zhao Mei-Qi Yang Tian-Sheng Li Jing-xiang Zhao yong-Chen Shang College of Chemistry Guangdong University of Petrochemical TechnologyMaoming525000China College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin150025China

The exploitation of cost-efficient electrocatalysts is critical to develop the hydrogen evolution reaction(HER) for hydrogen ***,Ni_(3)S_(2)/NF-x h(x=12,16 and 20,reaction time) nanocrystals in-situ grown on Ni foam(NF) were prepared via a facile hydrothermal *** results demonstrate that the reaction time plays key roles in the morphology,the hydrogen evolution performance of the samples,and the hydrogen brittleness of NF ***,the Ni_(3)S_(2)/NF-16 h displays outstanding catalytic activity for HER in alkaline solution and avoids the hydrogen brittleness of the NF skeletons *** afford a catalytic current of20 mA·cm^(-2),Ni_(3)S_(2)/NF-16 h presents ultra-low overpotential of 48 mV for hydrogen evolution and sufficient stability for 40 ***,the density functional theory(DFT) calculations revealed that the excellent electrocatalytic HER activity of Ni_(3)S_(2) could be attributed to its exposed(015) plane,which exhibited good capability for water adsorption and dissociation in an alkaline electrolyte,leading to the optimal free energy for H^(*) *** present work offers a novel strategy to design,synthesize and develop highly efficient electrocatalysts for HER.

关键词： Ni_(3)S_(2) Electrocatalysts Hydrogen evolution reaction Density functional theory calculations

Pollen tube,a one-way special train for special passengers

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Science Bulletin 2017年第17期62卷 1165-1166页

作者： Xiongpo Peng Meng-xiang sun College of Life Science Wuhan UniversityWuhan 430072China

Double fertilization is a specific characteristic of angiosperms,in which two sperm cells fuse with the egg and central cell respectively[1].Different from that of animals,the two sperm cells of angiosperms have lost their ***,to fulfill the double fertilization,the two immobile sperm cells have to be sent to the female games by a specific structure,the pollen *** landing on the stigma of the pistil,the pollen grain germinates and devel-

关键词：列车单向花粉管伸长精子细胞旅客中央细胞被子植物卵细胞

Fabrication and properties of silver-based composites reinforced with carbon-coated Ti_(3)AlC_(2)

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1836-1843页

作者： yong-fa Zhu Wu-bian Tian Dan-dan Wang Heng Zhang Jian-xiang Ding Pei-gen Zhang Zheng-ming sun Jiangsu Key Laboratory of Advanced Metallic Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China Key Laboratory of Metallurgical Emission Reduction&Resources Recycling Ministry of EducationSchool of Materials Science and EngineeringAnhui University of TechnologyMa’anshan 243002China

Ti_(3)AlC_(2)-reinforced Ag-based composites,which are used as sliding current collectors,electrical contacts,and electrode materials,exhibit remarkable ***,the interfacial reactions between Ag and Ti_(3)AlC_(2) significantly degrade the electrical and thermal properties of these *** diminish these interfacial reactions,we fabricated carbon-coated Ti_(3)AlC_(2) particles(C@Ti_(3)AlC_(2))as reinforcement and prepared Ag–10wt%C@Ti_(3)AlC_(2) composites with carbon-layer thicknesses ranging from 50–200 *** with the uncoated Ag–Ti_(3)AlC_(2) composite,Ag–C@Ti_(3)AlC_(2) was found to have a better distribution of Ti_(3)AlC_(2) *** increases in the carbon-layer thickness,the Vickers hardness value and relative density of Ag–C@Ti_(3)AlC_(2) gradually *** a carbon-layer thickness of 150 nm,we obtained the lowest resistivity of Ag–C@Ti_(3)AlC_(2) of 29.4135.5×10^(−9)Ω·m,which is half that of Ag–Ti_(3)AlC_(2)(66.7×10^(−9)Ω·m).The thermal conductivity of Ag–C@Ti_(3)AlC_(2) reached a maximum value of 135.5 W·m^(−1)·K^(−1) with a 200-nm carbon coating(~1.8 times that of Ag–Ti_(3)AlC_(2)).These results indicate that the carbon-coating method is a feasible strategy for improving the performance of Ag–C@Ti_(3)AlC_(2) composites.

关键词： silver-based composite titanium aluminum carbide carbon coating interfacial reaction properties

Mesomechanics coal experiment and an elastic-brittle damage model based on texture features

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International Journal of Mining Science and Technology 2018年第4期28卷 634-642页

作者： sun Chuanmeng Cao Shugang Li yong School of Electrical and Control Engineering North University of ChinaTaiyuan 030051China National Key Laboratory of Electronic Measurement Technology North University of ChinaTaiyuan 030051China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China College of Resources and Environmental Science Chongqi ng UniversityChongqing 400044China

To accurately describe damage within coal, digital image processing technology was used to determine texture parameters and obtain quantitative information related to coal meso-cracks. The relationship between damage and mesoscopic information for coal under compression was then analysed. The shape and distribution of damage were comprehensively considered in a defined damage variable, which was based on the texture characteristic. An elastic-brittle damage model based on the mesostructure information of coal was established. As a result, the damage model can appropriately and reliably replicate the processes of initiation, expansion, cut-through and eventual destruction of microscopic damage to coal under compression. After comparison, it was proved that the predicted overall stress-strain response of the model was comparable to the experimental result.

关键词： Mesomechanics experiment Image processing Texture feature Damage variable Damage model

Thiolated arsenicals in arsenic metabolism: Occurrence,formation, and biological implications

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Journal of Environmental Sciences 2016年第11期28卷 59-73页

作者： Yuzhen sun Guangliang Liu yong Cai Institute of Environment and Health Jianghan University Department of Chemistry and Biochemistry&Southeast Environmental Research Center Florida International University

Arsenic（As） is a notoriously toxic pollutant of health concern worldwide with potential risk of cancer induction, but meanwhile it is used as medicines for the treatment of different conditions including hematological cancers. Arsenic can undergo extensive metabolism in biological systems, and both toxicological and therapeutic effects of arsenic compounds are closely related to their metabolism. Recent studies have identified methylated thioarsenicals as a new class of arsenic metabolites in biological systems after exposure of inorganic and organic arsenicals, including arsenite, dimethylarsinic acid（DMAV）, dimethylarsinous glutathione（DMAIIIGS）, and arsenosugars. The increasing detection of thiolated arsenicals,including monomethylmonothioarsonic acid（MMMTAV）, dimethylmonothioarsinic acid（DMMTAV） and its glutathione conjugate（DMMTAVGS）, and dimethyldithioarsinic acid（DMDTAV） suggests that thioarsenicals may be important metabolites and play important roles in arsenic toxicity and therapeutic effects. Here we summarized the reported occurrence of thioarsenicals in biological systems, the possible formation pathways of thioarsenicals, and their toxicity, and discussed the biological implications of thioarsenicals on arsenic metabolism, toxicity, and therapeutic effects.

关键词： Arsenic Thioarsenicals Occurrence Formation pathways Toxicity

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椭圆节流小孔对空气静压轴承承载能力的影响

轴承 2025年第1期 39-45页

作者：孙国梁隆强刘华峰向俊谭畅四川航天烽火伺服控制技术有限公司成都611130

常规形状节流小孔在提高轴承性能时存在瓶颈,采用椭圆节流小孔能够更精确地控制气膜的流动和压力分布。为了计算椭圆节流小孔对空气静压轴承承载力的影响,通过引入椭圆小孔特性的扰动项对传统雷诺方程进行修正;为了避免不确定性和随机... 详细信息

常规形状节流小孔在提高轴承性能时存在瓶颈,采用椭圆节流小孔能够更精确地控制气膜的流动和压力分布。为了计算椭圆节流小孔对空气静压轴承承载力的影响,通过引入椭圆小孔特性的扰动项对传统雷诺方程进行修正;为了避免不确定性和随机因素导致的复杂计算问题,建立一种基于高斯分布的轴承承载力统计预测模型,实现了对椭圆小孔特征参数影响轴承承载力机制的分析;最后利用粒子群优化算法实现承载力与特征参数之间的最佳平衡。算例验证结果表明,长短轴比为0.8、小孔数量为20、小孔气道深度为9 mm的参数组合下的轴承承载力最优,约840 N。

关键词：滑动轴承气体静压轴承节流孔承载力粒子群优化算法

维普期刊数据库博看期刊

A Numerical Investigation of Vortex-Induced Vibration Response and Fatigue Damage for Flexible Cylinders Under Combined Uniform and Oscillatory Flow

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China Ocean Engineering 2020年第4期34卷 488-499页

作者： YUAN Yu-chao XUE Hong-xiang TANG Wen-yong State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Vortex-induced vibration(VIV)for flexible cylinders under combined uniform and oscillatory flow is a challenging and practical issue in ocean *** this paper,a time domain numerical model is adopted to investigate the characteristics of cross-flow VIV response and fatigue damage under different combined flow ***,the adopted VIV model and fatigue analysis procedure are validated well against the published experimental results of a4-m cylinder model under pure oscillatory ***,forty-five combined flow cases of the same cylinder model are designed to reveal the VIV response characteristics with different non-dimensional oscillation period T^*and combined ratio *** combined flow cases are classified into three categories to investigate the effect of r on cylinder’s dynamic response,and the effect of T*is described under long and short period ***,fatigue analysis is carried out to investigate how the structural fatigue damage varies with the variations of r and T^*.The captured characteristics of structural response and fatigue damage are explained through the VIV mechanism analysis.

关键词： vortex-induced vibration fatigue damage flexible cylinders combined flow

SOCIAL MEDIA RESEARCH:A REVIEW

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Journal of Systems Science and Systems Engineering 2013年第3期22卷 257-282页

作者： Junjie WU Haoyan sun yong TAN School of Economics and Management Beihang University Michael G.Foster School of Business University of Washington

Social media is fundamentally changing the way people communicate, consume and collaborate. It provides companies a new platform to interact with their customers. In academia, there is a surge in research efforts on understanding its effects. This paper aims to provide a review of current status of social media research. We discuss the specific domains in which the impacts of social media have been examined. A brief review of applicable research methodologies and approaches is also provided.

关键词： social media empirical models experimental methods analytical approaches predictive analytics

Integrated Control Strategy for CVT Powertrains with Consideration of Vehicle Drivability

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 515-523页

作者： sun Dongye LUO yong QIN Datong State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China

During shift,power flow is not interrupted in powertrains equipped with continuously variable transmission（CVT）.When hard acceleration is commanded,engine speed will flare and corresponding torque will be consumed,which leads to a drop in vehicle drive torque and also the vehicle *** is the reason why CVT vehicles have poor drivability during hard acceleration *** method such as torque compensation doesn＇t always work due to the limited backup torque of *** to this,means to evaluate the drivability of CVT vehicles are studied,affect factors of drivability are analyzed in *** acceleration process of CVT vehicle is studied by theoretical analysis,based on which engine torque and ratio change rate of CVT are identified as two key control parameters that decide the drivability of CVT vehicles during hard acceleration ***,a control strategy based on restricting the change rate of CVT ratio together with torque compensation is proposed,and two different algorithms to establish the limitation of ratio change rate are *** two algorithms are simulated and compared with each other,results indicate that drop of vehicle acceleration is eliminated evidently by limit the change rate of CVT ratio,but small ratio change rate also results in a longer time to finish the accelerate process,an algorithm to decide a proper ratio change rate is needed in order to tune these different *** order to get better control effects,a new fuzzy logic based algorithm is proposed to decide a proper ratio change rate during kick down conditions,simulation and experiment results indicate that,the amount of vehicle acceleration decrease is reduced from about 1 m/s2 to almost 0,in the mean time the accelerate process only delayed for about 0.3 *** proposed control strategy and algorithm can effectively tune the characteristics of CVT equipped vehicle during kick down conditions.

关键词： vehicles continuously variable transmission control strategy drivability

Interpretation of theη_(1)(1855)as a KK_(1)(1400)+***

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Science China(Physics,Mechanics & Astronomy) 2022年第6期65卷 60-66页

作者： xiang-Kun Dong yong-Hui Lin Bing-Song Zou CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Helmholtz-Institut fur Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universitat BonnBonn D-53115Germany School of Physics Central South UniversityChangsha 410083China

An exotic state with J^(PC)=1^(−+),denoted byη1(1855),was observed by BESIII Collaboration recently in J/ψ→γηη′.The fact that its mass is just below the threshold of KK_(1)(1400)stimulates us to investigate whether this exotic state can be interpreted as a KK_(1)(1400)+*** or *** the one boson exchange model,we show that it is possible for KK_(1)(1400)with J^(PC)=1^(−+)to bind together by taking the momentum cutoffΛ&2 GeV and yield the same binding energy as the experimental value whenΛ≈2.5 *** this molecular picture,the predicted branch ratio Br(η1(1855)→ηη′)≈15%is consistent with the experimental results,which again supports the molecular explanation ofη1(1855).Relevant systems,namely KK_(1)(1400)with JPC=1−−and KK_(1)(1270)with J^(PC)=1^(−±),are also investigated,some of which can be searched for in the future experiments.

关键词： hadronic molecule exotic hadrons one boson exchange