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Rare Metals 2023年第6期42卷 1836-1846页

作者： Yu Zhang Xue-ai Teng Ze-Qun Ma Rong-Ming Wang Woon-Ming Lau ai-xian shan Beijing Advanced Innovation Center for Materials Genome Engineering and Center for Green Innovation School of Mathematics and PhysicsUniversity of Science and Technology BeijingBeijing100083China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface ScienceSchool of Mathematics and PhysicsUniversity of Science and Technology BeijingBeijing100083China Shunde Innovation School of University of Science and Technology Beijing Foshan528000China Institute of Materials Science and Devices School of Materials Science and EngineeringSuzhou University of Science and TechnologySuzhou215009China

For catalytic materials,the characteristics of one-dimension and hollowness are the promotion factors for their full presentation of catalytic activity,and through a template-as sis ted method,both above superiorities can be fused ***,we proposed a novel strategy inspired by Pearson's principle with Cu_(2)O wires as templates,and prepared FeOOH hollow tubes,which covered by FeOOH *** applied as oxygen evolution reaction(OER)catalyst,the FeOOH scaly hollow tubes(FeOOH SHTs)showed outstanding catalytic activity with a low overpotential of 245 mV to drive a current density of10 mA·cm^(-2),excellent kinetics manifesting as a low Tafel slope of 46.9 mV·dec^(-1),and robust *** work provides a new synthesis strategy for an ideal OER catalyst,FeOOH,with high inherent activity and enhances the feasibility to broaden the design ideas of transition metalbased catalysts.

关键词： FeOOH scaly hollow tube(SHT) Cu_(2)O wire template One-dimensional(1D)hollow structure Oxygen evolution reaction(OER)

A Model for Predicting Dynamic Cutting Forces in Sand Mould Milling with Orthogonal Cutting

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 95-105页

作者： Zhong-De shan Fu-xian Zhu State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science TechnologyBeijing 100083China Jiangsu University of Technology Changzhou 213001China

Cutting force is one of the research hotspots in direct sand mould milling because the cutting force directly a ects the machining quality and tool wear. Unlike metals, sand mould is a heterogeneous discrete deposition material. There is still a lack of theoretical research on the cutting force. In order to realize the prediction and control of the cut?ting force in the sand mould milling process, an analytical model of cutting force is proposed based on the unequal division shear zone model of orthogonal cutting. The deformation velocity relations of the chip within the orthogonal cutting shear zone are analyzed first. According to the flow behavior of granular, the unequal division shear zone model of sand mould is presented, in which the governing equations of shear strain rate, strain and velocity are estab?lished. The constitutive relationship of quasi?solid–liquid transition is introduced to build the 2D constitutive equation and deduce the cutting stress in the mould shear zone. According to the cutting geometric relations of up milling with straight cutting edge and the transformation relationship between cutting stress and cutting force, the dynamic cutting forces are predicted for di erent milling conditions. Compared with the experimental results, the predicted results show good agreement, indicating that the predictive model of cutting force in milling sand mould is validated. Therefore, the proposed model can provide the theoretical guidance for cutting force control in high e ciency mill?ing sand mould.

关键词： Green manufacture Cutting force Sand mould milling Orthogonal cutting Quasi?solid–liquid transition

Event-based optimization with random packet dropping

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Science China(Information Sciences) 2020年第11期63卷 175-194页

作者： Qing-shan JIA Jing-xian TANG Zhenning LANG Center for Intelligent and Networked Systems Department of AutomationTsinghua University NetEase Inc.

Event-based optimization(EBO) provides a general framework for policy optimization in many discrete event dynamic systems where decision making is triggered by events that represent state transitions with common features. Because the number of events can be defined by the user and usually increases linearly with respect to the system scale, EBO has good potential to address large-scale problems where the state space grows exponentially. However, in many practical systems, sensors are geographically distributed and connected to a central controller through imperfect communication channels. Therefore, events observed by the sensors may not reach the controller. Optimization methods of event-based policies in these cases have not yet been identified. In this paper, we consider this important problem and make three major contributions. First, we formulate a mathematical EBO model in which the communication between sensors and controllers is subject to random packet dropping. Second, we show that this EBO model can be converted to another EBO model with perfect communication. Then, the performance difference equation and the performance derivative equation for event-based policies are straightforward to develop. One gradient-based policy iteration algorithm is developed for problems where the state transition probabilities are explicitly known, while another for problems where they are unknown. Third, the performance of the algorithms and the impact of the packet dropping probability on policy performance are numerically demonstrated on a single-zone occupant level estimation problem in buildings.

关键词： event-based optimization packet dropping discrete event dynamic systems

Reduction of NO_(x)emission based on optimized proportions of mill scale and coke breeze in sintering process

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International Journal of Minerals,Metallurgy and Materials 2021年第9期28卷 1453-1461页

作者： Zhi-gang Que xian-bin ai Sheng-li Wu Institute of Energy Research Jiangxi Academy of ScienceNanchang 330096China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Reducing NO_(x) emission of iron ore sintering process in a cost effective manner is a challenge for the iron and steel industry at *** of the proportion of mill scale and coke breeze on the NO_(x) emission,strength of sinter,and sinter indexes were studied by com-bustion and sinter pot *** showed that the peak value of NO concentration,total of NO emission,and fuel-N conversion rate gradu-ally decreased as the proportions of the mill scale increased because NO was reduced to N_(2) by Fe_(3)O_(4),FeO,and Fe in the mill *** strength of sinter reached the highest value at 8.0wt%mill scale due to the formation of minerals with low melting *** fuel-N conver-sion rate slightly fluctuated and total NO_(x) emission significantly decreased with the decreased proportions of coke breeze because CO forma-tion and content of N element in the sintered mixture ***,the sinter strength also decreased due to the decrease in the amount of the melting ***,results of the sinter pot tests indicated that NO_(x) emission *** sinter indexes performed well when the proportions of mill scale and coke breeze were 8.0wt%and 3.70wt%respectively in the sintered mixture.

关键词： iron ore sinter NO_(x)emission mill scale coke breeze proportion optimization

Combustion mechanism of benzene in iron ore sintering process:experimental and simulation

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Journal of Iron and Steel Research International 2024年第1期31卷 195-203页

作者： Zhi-gang Que Jin-ming Shi xian-bin ai Institute of Energy Research Jiangxi Academy of ScienceNanchang330096JiangxiChina Jiangxi Carbon Neutralization Research Center Nanchang330096JiangxiChina

Benzene is a typical component of volatile organic compounds(VOCs)in the iron ore sintering flue *** combustion behavior of benzene directly affects the emission of VOCs in iron ore sintering *** effects of temperature,benzene,and oxygen concentrations on the conversion ratio of benzene were investigated by experiments and numerical *** experiments were carried out in a tube reactor at temperatures of 773-1098 K,benzene concentrations of 0.01-0.03 vol.%,and oxygen concentrations of 10-21 vol.%.The numerical simulation was performed with the plug flow model in the CHEMKIN program based on a kinetic model that consists of 132 chemical species and 772 elementary step-like *** experimental results reveal that increasing the temperature and benzene concentration could signifi-cantly promote benzene *** is attributed to the increase in the reaction rates of all steps in the pathway for forming CO_(2)and H_(2)*** addition,due to the large equivalent ratio of oxygen to benzene,the conversion ratio of benzene remained constant at different oxygen *** simulation results were in good agreement with the experimental results and indicated that six elementary reactions dominated the formations of CO_(2)and H_(2)*** oxidations of C_(6)H_(5)O,CO,and C_(5)H_(4)O intermediates to CO_(2)were the limiting steps in the reaction pathways.

关键词： Benzene Volatile organic compound Iron ore sinter Combustion Simulation Temperature Oxygen

The intra-neuroendoscopic technique: a new method for rapid removal of acute severe intraventricular hematoma

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Neural Regeneration Research 2018年第6期13卷 999-1006页

作者： Bo Du ai-Jun shan Yu-Juan Zhang Jin Wang Kai-Wen Peng xian-Liang Zhong Yu-Ping Peng Department of Neurosurgery Nanfang Hospital Southern Medical University Department of Emergency Medicine Shenzhen People's Hospital The Second Affiliated Hospital of Jinan University

The mortality rate of acute severe intraventricular hematoma is extremely high, and the rate of disability in survivors is high. Intraventricular hematoma has always been a difficult problem for clinical treatment. Although minimally invasive endoscopic hematoma evacuation is widely used to treat this disease, the technique still has room for improvement. Equipment for the intra-neuroendoscopic technique（INET） consists of two of our patented inventions： a transparent sheath（Patent No. ZL 200820046232.0） and a hematoma aspirator（Patent No. ZL 201520248717.8）. This study explored the safety and efficacy of INET by comparing it with extraventricular drainage in combination with urokinase thrombolytic therapy. This trial recruited 65 patients with severe intraventricular hemorrhage, including 35（19 men and 16 women, aged 53.2 ± 8.7 years） in the INET group and 30（17 men and 13 women, aged 51.5 ± 7.9 years） in the control group（extraventricular drainage plus urokinase thrombolytic therapy）. Our results showed that compared with the control group, the INET group exhibited lower intraventricular hemorrhage volumes, shorter intensive care-unit monitoring and ventricular drainage-tube placement times, and fewer incidences of intracranial infection, secondary bleeding, and mortality. Thus, the prognosis of survivors had improved remarkably. These findings indicate that INET is a safe and efficient new method for treating severe intraventricular hematoma. This trial was registered with Clinical ***（NCT02515903）.

关键词： nerve regeneration ventricular hemorrhage transparent sheath extraventricular drainage minimally invasive surgery intra-neuroendoscopic technique urokinase thrombolysis prognosis neural regeneration

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预处理工艺对皂荚籽脱壳性能的影响

农机化研究 2025年第3期47卷 162-168页

作者：李娜李姜维徐鹏云线承源王杉河北农业大学机电工程学院河北保定071000 河北省智慧农业装备技术创新中心河北保定071001

针对人工剥离皂荚米功效低、成本高,以及现有皂荚籽机械化脱壳装置去壳过程繁琐、脱壳不充分,需循环脱壳且脱壳率低的问题,以分级后安徽省亳州市产皂荚籽为研究对象,提出了一种通过一定浓度的塔塔粉蒸煮皂荚籽后再烘干的预处理工艺。通... 详细信息

针对人工剥离皂荚米功效低、成本高,以及现有皂荚籽机械化脱壳装置去壳过程繁琐、脱壳不充分,需循环脱壳且脱壳率低的问题,以分级后安徽省亳州市产皂荚籽为研究对象,提出了一种通过一定浓度的塔塔粉蒸煮皂荚籽后再烘干的预处理工艺。通过自主设计的碾搓式皂荚籽脱壳装置,以脱壳率为评价指标,通过单因素试验和正交试验,分析蒸煮时间、塔塔粉浓度与烘干时间在不同水平下的脱壳效果。试验结果表明:随着塔塔粉浓度的增大,脱壳率先增大后减小;随着蒸煮时间和烘干时间的增加,脱壳率逐渐增大后再逐渐趋于平稳。通过Design-Expert软件分析试验数据,结果显示:对皂荚籽脱壳率影响显著性由小到大的顺序为蒸煮时间、烘干时间、塔塔粉浓度。建立皂荚籽脱壳的回归数学模型并优化求解一组最优参数组合,即蒸煮时间为90 min,塔塔粉浓度为3%,烘干时间为8 h,此条件下脱壳率达到84.42%。

关键词：皂荚籽预处理工艺脱壳率

Dual-cavity beam arrival time monitor design for the shanghai soft X-ray FEL facility

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Nuclear Science and Techniques 2019年第5期30卷 14-21页

作者： shan-shan Cao Ren-xian Yuan Jian Chen Yong-Bin Leng shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

Free electron lasers provide high-power and ultrashort pulses with extreme brightness. In order to improve a facility's capabilities and explore the possibility of performing high-resolution time-resolved experiments, a beam arrival time resolution under 100 fs is required. In this article, a novel beam arrival time monitor(BAM)equipped with two cavities has been designed and a beam flight time measurement scheme based on the BAM prototype has been proposed to estimate phase jitter in the signal measurement system. The two BAM cavities work at different frequencies and the frequency difference is designed to be 35 MHz. Therefore, a self-mixing intermediate frequency signal can be generated using the two cavities. The measured beam flight time shows a temporal deviation of 37 fs(rms).

关键词： Beam arrival time monitor Dual-cavities Beam flight time Self-mixing

Well production optimization using streamline features-based objective function and Bayesian adaptive direct search algorithm

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Petroleum Science 2022年第6期19卷 2879-2894页

作者： Qi-Hong Feng shan-shan Li xian-Min Zhang Xiao-Fei Gao Ji-Hui Ni School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina shandong Institute of Petroleum and Chemical Technology Dongying257061ShandongChina CNOOC China Limited Shenzhen BranchShenzhen518000GuangdongChina

Well production optimization is a complex and time-consuming task in the oilfield *** combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well *** method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization *** improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is *** new objective function,which represents the water flooding potential,is extracted from streamline *** only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the *** the well production optimization model is established and solved by the BADS *** feasibility of the new objective function and the efficiency of this optimization method are verified by three *** demonstrate that the new objective function is positively correlated with the cumulative oil *** the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization ***,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional *** can provide a more effective basis for determining the optimal well production for actual oilfield development.

关键词： Well production Optimization efficiency Streamline simulation Streamline feature Objective function Bayesian adaptive direct search algorithm

Engineering morphologies of cobalt oxide/phosphate-carbon nanohybrids for high-efficiency electrochemical water oxidation and reduction

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Journal of Energy Chemistry 2021年第1期30卷 139-146,I0005页

作者： shan-shan Xu xian-Wei Lv Yan-Mei Zhao Tie-Zhen Ren Zhong-Yong Yuan Hebei Provincial Key Laboratory of Green Chemical Technology&High Efficient Energy Saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin 300350China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021NingxiaChina

Active non-noble metal catalysts plays a decisive role for water electrolysis,however,the rational design and development of cost-efficient electrocatalysts with Pt/IrO2-like activity is still a challenging ***,a facile one-step electrodeposition route in deep eutectic solvents(DESs) is developed for morphology-controllable synthesis of cobalt oxide/phosphate-carbon nano hybrids on nickel foam(CoPO@C/NF).A series of CoPO@C/NF nanostructures including cubes,octahedrons,microspheres and nanoflowers are synthesized,which show promising electrocatalytic properties toward oxygen and hydrogen evolution reactions(OER/HER).Such surface self-organized microstructure with accessible active sites make a significant contribution to the enhanced electrochemical activity,and hybridizing cobalt oxide with cobalt pyrophosphates and carbon can result in enhanced OER performance through synergistic *** all nanostructures,the obtained microspherical CoPO@C/NF-3 catalyst exhibits excellent catalytic activities for OER and HER in 1.0 M KOH,affording an anodic current density of 10 mA cm^(-2) at overpotentials of 293 mV for OER and 93 mV for HER,with good long-time *** work offers a practical route for engineering the high-performance electrocatalysts towards efficient energy conversion and storage devices.

关键词： Cobalt-based electrocatalysts Oxygen evolution reaction Hydrogen evolution reaction Deep eutectic solvents Electrodeposition