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Journal of Energy Chemistry 2016年第1期25卷 35-40页

作者： xiangyang zhou Hongcheng Li Juan Yang School of Metallurgy and Environment Central South University

Activated carbons for electrochemical capacitor electrodes are prepared from soyabean using chemical activation with KOH. The pore size is easily controllable by changing the mass ratio between KOH and carbonized product. The as-prepared materials possess a large specific surface area, unique structure, well- developed hierarchical porosity and plentiful heteroatoms（mainly O and N）. Thus resulted in its high specific capacitance,good rate capacity and cycling stability. Moreover, attributing to worldwide availability, renewable nature and low-cost, activated carbon prepared from soyabean has a good potential in energy conversion and storage devices.

关键词： Electrochemical capacitor Activated carbon Soyabean Heteroatoms

Novel foaming agent used in preparation process of aluminum foams

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Journal of University of Science and Technology Beijing 2008年第6期15卷 735-739页

作者： xiangyang zhou Xiquan Liu Jie Li Hongzhuan Liu School of Metallurgical Science and Engineering Central South University Changsha 410083 China

The performances of a novel foaming agent used in the preparation process of aluminum foams were investigated, and the effects of some factors, such as addition of the foaming agent, foaming temperature on the porosity, and appearance of aluminum foams were also discussed. Experimental results show that the novel foaming agent has a wide decomposition temperature range and a mild decomposed rate; the foaming agent has the ability to enhance the viscosity of aluminum melt, as a result, an extra viscosifier such as Ca or SiCp is unnecessary while using this foaming agent; the bubble-free zone in material decreases and the foaming effi- ciency increases with the increase of foaming agent; the bubble-free zone disappears and the foaming efficiency is near 100% when the addition of foaming agent is more than 1.4wt%; the porosity of the aluminum foam increases with the increase of foaming agent when the addition of foaming agent is less than 2.2wt%.

关键词： aluminum foam foaming agent porosity viscosity foaming efficiency

Preparation of special silicon steel grade MgO from hydromagnesite

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Journal of University of Science and Technology Beijing 2007年第3期14卷 225-230页

作者： xiangyang zhou Shanni Li Jie Li Hongzhuan Liu Shangyuan Wu School of Metallurgical Science and Engineering Central South University Chang sha 410083 China School of Biological Science and Technology Central South University Chang sha 410083 China

A preparation technology of MgO powder used in special silicon steel from hydromagnesite mineral has been developed. The preparation technology includes the following steps：（1） calcining the hydromagnesite at 700-750°C for 1.5-2 h; （2） hydrating the calcined hydromagnesite to be slurry containing the solid-liquid ratio of 15-20 g？L？1; （3） acquiring Mg（HCO3）2 solution by carbonating the slurry, the carbonation temperature, CO2 pressure, and end point PH value of carbonation are less than 40°C, 0.4-0.6 MPa, and 7 respectively during the carbonation process; （4） preparing precipitated basic magnesium carbonate by thermally decomposing the Mg（HCO3）2 solution at 90-100°C; （5） obtaining the MgO product by calcining the precipitated basic magnesium carbonate at 850-950°C for 30-60 min, and adopting flowing nitrogen during the cooling process. By using this technology, more than 80wt% magnesium in hydromagnesite mineral can be extracted, and high-performance MgO products used in special silicon steel can be ob- tained.

关键词： special silicon steel grade MgO hydromagnesite mineral carbonation end point pH value

Pore size effects of nanoporous carbons with ultra-high surface area on high-pressure hydrogen storage

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Journal of Energy Chemistry 2015年第1期24卷 1-8页

作者： Zhen Geng Cunman Zhang Dabin Wang xiangyang zhou Mei Cai Clean Energy Automotive Engineering Center Tongji University School of Materials Science and Technology Tongji University School of Automotive Studies Tongji University Research & Development Center General Motors

In this work, the morphologies and pore structures of a series of corncob-derived activated carbons and zeolite templated carbon with ultrahigh surface area were carefully investigated by SEM, HRTEM and N2-sorption characterization technologies. The high-pressure hydrogen uptake performance was analyzed using standard Pressure-Composition-Temperature apparatus in order to study the pore size effects on hydrogen uptake. These as-obtained porous carbons showed different characteristics of pore size distribution as well as specific surface area. The results indicate that the most effective pores for adsorbing hydrogen depended on the storage pressure. These ultramicropores （0.65-0.85 nm） could be the most effective pores on excess H2 uptake at 1 bar, however, micropores （0.85-2 nm） would play a more important role in excess H2 uptake at higher pressure at 77 K. At room temperature, pore size effects on H2 uptake capacity were very weak. Both specific surface area and total pore volume play more important roles than pore size for H2 uptake at room temperature, which was clearly different from that at 77 K. For applications in future, the corncob-derived activated carbons can be more available than zeolite templated carbons at 77 K. Element doping enhanced hydrogen uptake could be main research direction for improving H2 uptake capacity at room temperature.

关键词： corncob activated carbon zeolite templated carbon hydrogen storage pore size effect

Temporal and spatial evolution of global major grain trade patterns

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Journal of Integrative Agriculture 2024年第3期23卷 1075-1086页

作者： Ziqi Yin Jiaxuan Hu Jing Zhang xiangyang zhou Lingling Li Jianzhai Wu Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081China Institute of Scientific and Technical Information of China Beijing 100038China Zibo Agricultural Science Research Institute Zibo 255000China Zibo Institute for Digital Agriculture and Rural Research Zibo 255000China

The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain trade from 1990 to 2020, focusing on network topology, centrality ranking, and community structure. There are three major findings. First, the global major grain trade network has expanded in scale, with a growing emphasis on diversification and balance. During the study period, the United States, Canada, China, and Brazil were the core nodes of the network. Grain-exporting countries were mainly situated in Asia, the Americas, and Europe, and importing countries in Asia, Africa, and Europe. Second, a significant increase in the number of high centrality countries with high export capacity occurred, benefiting from natural advantages such as fertile land and favorable climates. Third, the main global grain trade network is divided into four communities, with the Americas-Europe community being the largest and most widespread. The formation of the community pattern was influenced by geographic proximity, driven by the core exporting countries. Therefore, the world needs to enhance the existing trade model, promote the multi-polarization of the grain trade network, and establish a global vision for the future community. Countries and regions should participate actively in global grain trade security governance and institutional reform, expand trade links with other countries, and optimize import and export policies to reduce trade risks.

关键词： grain trade pattern evolution complex network

Core@shell sulfur@polypyrrole nanoparticles sandwiched in graphene sheets as cathode for lithium–sulfur batteries

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Journal of Energy Chemistry 2015年第4期24卷 448-455页

作者： xiangyang zhou Feng Chen Juan Yang School of Metallurgy and Environment Central South University

A nano sulfur-based composite cathode material featured by uniform core@shell-structured sulfur@polypyrrole nanoparticles sandwiched in three-dimensional graphene sheets conductive network（S@PPy/GS） is fabricated via a facile solution-based method. The S@PPy nanoparticles are synthesized by in situ chemical oxidative polymerization of pyrrole on the surface of sulfur particles,and then graphene sheets are covered outside the S@PPy nanoparticles,forming a three-dimensional conductive network. When evaluating the electrochemical performance of S@PPy/GS in a lithium–sulfur battery,it delivers large discharge capacity,excellent cycle stability,and good rate capability. The initial discharge capacity is up to 1040 m Ah/g at 0.1 C,the capacity can remain 537.8 m Ah/g at 0.2 C after 200 cycles,even at a higher rate of 1 C,the specific capacity still reaches 566.5 m Ah/g. The good electrochemical performance is attributed to the unique structure of S@PPy/GS,which can not only provide an excellent transport of lithium and electron ions within the electrodes,but also retard the shuttle effect of soluble lithium polysulfides effectively,thus plays a positive role in building better lithium-sulfur batteries.

关键词： Nano sulfur Conductive polymer Core@shell structure Graphene coating Lithium–sulfur battery

RAPID QUENCHING AND LARGE UNDERCOOLING IN MULTISTAGE RAPID SOLIDIFICATION POWDER-MAKING PROCESS

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中国有色金属学会会刊：英文版 1993年第3期3卷 29-35页

作者： Chen, Zhenhua Jiang, xiangyang zhou, Duosan Wang, Yun Huang, Peiyun Central-South University of Technology, Changsha 410083, China

The rapid quenching and large undercooling phenomena and device working principle in the rapid solidification process are analyzed, and the working characteristics are presented in detail. The results show that these ... 详细信息

关键词： rapid quenching large undercooling multistage rapid salidification powder-making

Optimization of a Network Topology Generation Algorithm Based on Spatial Information Network

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国际计算机前沿大会会议论文集 2023年第1期 246-255页

作者： Peng Yang Shijie zhou xiangyang zhou School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu 610054People’s Republic of China Huawei Technologies Co. Ltd.Chengdu 611730People’s Republic of China

Spatial information network(SIN)is a network with high speed and periodicity of node *** recent days,China will build a complete asteroid monitoring and warning system and a near-Earth asteroid defense *** requires launching more low-Earth orbit *** order to adapt to the increase in the number of near-Earth satellites,the dynamic optimization of space informa-tion network topology between satellites will have research signiﬁ***-ering the visibility of satellite networking,the connectivity of satellite nodes,and the number of links connected to the whole network,with the goal of minimizing the end-to-end delay between satellite nodes in the network as the optimization goal,a network topology optimization model that meets multiple constraints is constructed,and the model is solved using greedy algorithm and simulated anneal-ing *** the process of simulated annealing,the networkﬂow algorithm is innovatively proposed for neighborhood *** show that the simulated annealing hybrid neighborhood algorithm is signiﬁcantly better than the simulated annealing random neighborhood algorithm.

关键词： Spatial Information Network Dynamic Optimization of Network Topology Network Flow Algorithm Simulated Annealing Algorithm

Effects of thermal activation conditions on the microstructure regulation of corncob-derived activated carbon for hydrogen storage

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Journal of Energy Chemistry 2014年第5期23卷 601-608页

作者： Dabin Wang Zhen Geng Cunman Zhang xiangyang zhou Xupeng Liu Clean Energy Automotive Engineering Center Tongji University School of Automotive Studies Tongji University School of Materials Science and Technology Tongji University

Activated carbons derived from corncob （CACs） were prepared by pyrolysis carbonization and KOH activation. Through modifying activation conditions, samples with large pore volume and ultrahigh BET specific surface area could be obtained. The sample achieved the highest hydrogen uptake capacity of 5.80 wt% at 40 bar and -196℃ The as-obtained samples were characterized by N2-sorption, transmission electron microscopy （TEM） and scanning electron microscopy （SEM）. Besides, thermogravimetric analysis was also employed to investigate the activation behavior of CACs. Detailed investigation on the activation parameters reveals that moderate activation temperature and heating rate are favorable for preparing CACs with high surface area, large pore volume and optimal pore size distribution. Meanwhile, the micropore volume between 0.65 nm and 0.85 nm along with BET surface area and total pore volume has great effects on hydrogen uptake capacities. The present results indicate that CACs are the most promising materials for hydrogen storage application.

关键词： corncob-derived activated carbon KOH activation activation conditions hydrogen storage

Reduced-order design of Robust H_∞ Controller for an Inertial Stabilized Aerial Platform

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Instrumentation 2019年第3期6卷 2-9页

作者： xiangyang zhou Yuqian LI Chao YANG School of Instrumentation and Optoeletronic Engineering Beihang University(BUAA)Beijing 100191China Beijing Academy of Quantum Information Sciences Beijing 100193China

The uncertainty disturbance is one of the main disturbances that seriously influences the stabilization precision of an aerial inertially stabilized platform(ISP)*** this paper,to improve the stabilization precision of the ISP under disturbance uncertainty,a robust H∞controller is designed in this ***,the reduction order is carried out for high-order controllers generated by the robust H∞loop shaping control *** application of the minimum implementation and balanced truncation algorithm in controller reduction is ***,the principle of reduced order of minimum implementation and balanced truncation are ***,the method is used to reduce the order of the high-order robust H∞loop shaping ***,the method is analyzed and verified by the simulations and *** results show that by the reduced-order method of minimum implementation and balanced truncation,the stabilization precision of the robust H∞loop shaping controller is increased by about 10%.

关键词： Aerial Remote Sensing Inertial Stabilization Platform Robust H_∞Control Controller Reduction Balanced Truncation