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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 293-307页

作者： Hong-Jiang Wan Xiao-Qi Wu Hong-Liang ming Jian-Qiu wang En-Hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Northeastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangzhou510530China

The effects of hydrogen charging time and pressure on the hydrogen embrittlement(HE)susceptibility of X52.pipeline steel material are studied by slow strain rate tensile *** fracture morphologies of the specimens are observed by scanning electron *** HE susceptibility of the X52.pipeline steel material increases with an increase in both hydrogen charging time and hydrogen *** a charging time of 96 h,the HE susceptibility index reaches 45.86%,approximately 3.6 times that at a charging time of 0 ***,a charging pressure of 4 MPa results in a HE susceptibility index of 31.61%,approximately 2.5 times higher than that at a charging pressure of 0.3 MPa.

关键词： Hydrogen embrittlement X52.pipeline steel material Tubular specimen Hydrogen charging time Hydrogen charging pressure

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-Qing Li Wen-Hao wang Yuan-Da Su Jun-Xin Guo Xiao-ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Investigation of the failure mechanism and theoretical model of bolt-reinforced shallow tunnel faces with different bolt lengths

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Underground Space 2024年第3期16卷 126-142页

作者： Xiao Zhang Li Yu mingnian wang Henghong Yang ming Lu Zexing Li Langzhou Tang School of Civil Engineering Southwest Jiaotong UniversityChengdu 610036SichuanChina Key Laboratory of Traffic Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610036SichuanChina School of Transportation and Logistics Southwest Jiaotong UniversityChengdu 610036SichuanChina

Using fiberglass bolts to reinforce a tunnel face is a practical auxiliary technology for ensuring tunnel face stability in soft *** reinforcing effect and the economics of this technology are significantly affected by bolt ***,to date,the failure mechanism of bolt-reinforced tunnel faces with different bolt lengths has rarely been *** reveal the failure mechanism of bolt-reinforced shallow tunnel faces,in this study,the stability of bolt-reinforced tunnel faces with different bolt lengths was investigated by using laboratory tests and numerical simulations,and a simplified theoretical model for practical engineering was *** face support pressure and failure pattern for different bolt lengths during the face collapse process were obtained,and the influence of bolt length on face stability was clearly *** specifically,the results show that face stability increases with increasing bolt length,and the reinforcing effect of face bolts is governed by the shear failure at the soil-grout interface first in the stable zone of the tunnel face and then in the failure *** the bolt length in the stable zone is larger than that in the failure zone,face stability will not be improved with increasing bolt length;thus,this bolt length is referred to as the optimal bolt length L_(opt).The L_(opt)value is slightly larger than the initial failure range(in the unreinforced condition)and can be approximately calculated by L_(opt)=(1-0.0133u)D(u is the friction angle of the soil,and D is the tunnel diameter)in practical ***,a simplified theoretical model was established to analyse the stability of reinforced tunnel faces,and the results are in good agreement with both laboratory tests and numerical *** proposed model can be used as an efficient tool for the design of face bolts.

关键词： Failure mechanism Face bolting Tunnel face stability Bolt length Reinforcing mechanism

Interfacial engineering of the layered oxide cathode materials for sodium-ion battery

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Nano Research 2024年第3期17卷 1441-1464页

作者： Quanqing Zhao Ruru wang ming Gao Faheem KButt Jianfeng Jia Haishun Wu Youqi Zhu Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuan 030032China Metals and Chemistry Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China Department of Physics Division of Science and TechnologyUniversity of EducationLahore 54770Pakistan Research Center of Materials Science Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green ApplicationsBeijing Institute of TechnologyBeijing 100081China

The layered metal oxides are reviewed as the hopeful cathode materials for high-performance sodium-ion batteries(SIBs)due to their large theoretical capacity,favorable two-dimensional(2.)ion diffusion channel,and simple ***,their cycling stability,rate capability,and thermal stability are still significantly concerned and highlighted before further practical *** chemical,mechanical and electrochemical stability of the cathode–electrolyte interfaces upon cycling is of great ***,the unique structural and electrochemical properties of the layered oxide cathode materials for SIB are *** mechanism of bulk/surface degradation induced by oxygen evolution,phase transition,microcrack,and electrolyte decomposition is thoroughly ***,the interfacial engineering to construct stable interface through various effective methods is fully *** future outlook and challenges for interfacial engineering in this filed are also *** review should shed light on the rational design and construct of robust interface for applications of superior layered oxide cathodes in SIB and may suggest future research directions.

关键词： interfacial engineering sodium-ion battery layered oxide electrolyte interface

Influence of stearic acid surface modification on flowability and agglomeration of battery grade Li_(2.CO_(3)powder

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Particuology 2024年第9期92卷 263-277页

作者： ming Zhou Lithium Industry Center Zhejiang New Era Zhongneng Technology Co.Ltd.Shaoxing312000China

This work investigates the flow and agglomeration behaviors of battery grade Li_(2.CO_(3)powder and the influence of stearic acid surface *** degree of agglomeration is directly related to the uniformity of Li_(2.CO_(3)and its powder *** to the Chinese National Nonferrous Metal Industry Standard,battery grade Li_(2.CO_(3)powder has D50 equal to 3–8μm which belongs to a micron-sized superfine ***,with the extension of storage time,the serious agglomeration phenomenon occurs due to the large specific surface area and rough and irregular powder *** Hausner ratio(HR)of the unmodified sample increases from 1.14 to 1.41,and the corresponding flowability is classified as good to ***,among samples with doping stearic acid,the optimum amount of it is 0.10 wt%which exhibits an extremely stable HR value from 1.14 to ***,after 156 days,the repose angle(AR)obtained for samples without surface modification and using 0.10 wt%stearic acid are calculated to be 49°and 2.°,*** on the values of HR and AR,the flowability of the unmodified sample is poor while the sample modified with 0.10 wt%of stearic acid still maintain excellent powder flow ***,The LiMn_(2.O_(4)cathode material synthesized from modified Li_(2.CO_(3)powder with a stearic acid content of 0.10 wt%exhibits good crystallinity and comparable electrochemical performance to that prepared by commercial Li_(2.CO_(3).These results indicate that stearic acid has the potential to be an ideal modifier for battery grade Li_(2.CO_(3)powder that needs to be kept for a long time.

关键词： Battery grade Li_(2.CO_(3)powder Flowability Surface modification Stearic acid

Inter-stage performance and energy characteristics analysis of electric submersible pump based on entropy production theory

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Petroleum Science 2024年第2期21卷 1354-1368页

作者： Hui wang Yang Yang Bin Xi Wei-Dong Shi Chuan wang Lei-Lei Ji Xiang-Yu Song Zhao-{2. He College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou225009JiangsuChina College of Electrical and Mechanical Engineering Nanchang Institute of TechnologyNanchang330044JiangxiChina College of Mechanical Engineering Nantong UniversityNantong226019JiangsuChina National Research Center of Pumps Jiangsu UniversityZhenjiang212013JiangsuChina Zhejiang Zhenxing Petrochemical Machinery Co. Ltd.Ruian325204ZhejiangChina Department of Mechanical Engineering of Texas Tech University Lubbock79411TXUSA

The electric submersible pump(ESP) is a crucial apparatus utilized for lifting in the oil extraction *** lifting capacity is enhanced by the multi-stage tandem structure, but variations in energy characteristics and internal flow across stages are also introduced. In this study, the inter-stage variability of energy characteristics in ESP hydraulic systems is investigated through entropy production(EP) analysis,which incorporates numerical simulations and experimental validation. The EP theory facilitates the quantification of energy loss in each computational subdomain at all ESP stages, establishing a correlation between microscopic flow structure and energy dissipation within the system. Furthermore, the underlying causes of inter-stage variability in ESP hydraulic systems are examined, and the advantages and disadvantages of applying the EP theory in this context are evaluated. Consistent energy characteristics within the ESP, aligned with the distribution of internal flow structure, are provided by the EP theory, as demonstrated by our results. The EP theory also enables the quantitative analysis of internal flow losses and complements existing performance analysis methods to map the internal flow structure to hydraulic losses. Nonetheless, an inconsistency between the energy characterization based on EP theory and the traditional efficiency index when reflecting inter-stage differences is identified. This inconsistency arises from the exclusive focus of the EP theory on flow losses within the flow field, disregarding the quantification of external energy input to the flow field. This study provides a reference for the optimization of EP theory in rotating machinery while deeply investigating the energy dissipation characteristics of multistage hydraulic system, which has certain theoretical and practical significance.

关键词： Electric submersible pump(ESP) Entropy production theory Energy characteristics Inter-stage differences

A review of ultra-high temperature heat-resistant energetic materials

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Defence Technology（防务技术） 2024年第8期38卷 33-57页

作者： Rongzheng Zhang Yuangang Xu Feng Yang Pengcheng wang Qiuhan Lin Hui Huang ming Lu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

Heat-resistant energetic materials refer to a type of energetic materials that possess a high melting point,high stability and operational safety. By studying the structures of these energetic materials has showed that the thermal stability can be enhanced by introducing amino groups to form intra/inter-molecular hydrogen bonds, constructing conjugate systems and designing symmetrical structures. This article aims to review the physical and chemical properties of ultra-high temperature heat-resistant energetic compounds and provide valuable theoretical insights for the preparation of ultra-high temperature heatresistant energetic materials. We also analyze the selected 2. heat-resistant energetic materials with decomposition temperatures higher than 350℃, serving as templates for the synthesis of various highperformance heat-resistant energetic materials.

关键词： Heat-resistant energetic materials Organic synthesis Conjugated Hydrogen bond Symmetrical structure Stabilization

Degradation mechanisms and stabilization strategies of ruthenium-based catalysts for OER in the proton exchange membrane water electrolyzer

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Progress in Natural Science:Materials International 2024年第1期34卷 207-222页

作者： ming Yang Hongxiang Wu Zhaoping Shi Yibo wang Jiahao Yang Jing Ni Pengbo wang Yuqing Cheng Ziang wang Meiling Xiao Changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of Applied Chemistry and Engineering University of Science and Technology of China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Designing economical oxygen evolution reaction(OER) electrocatalysts with high activity and long-term stability is essential to promote the scale-up applications of proton exchange membrane water electrolyzer(PEMWE) for hydrogen production. Ruthenium(Ru)-based materials with high intrinsic activity are hailed as the most promising catalysts, but still infeasible for practical application considering their long unresolved poor stability(only dozens of lifespan). Thus, tremendous efforts have been devoted to uncovering the degradation mechanisms and developing stabilization strategies for the Ru-based catalysts. In this review, starting from summarizing the fundamental understanding of deactivation mechanisms, a picture of the stability issue of Ru-based catalysts is proposed, which is followed by a detailed discussion on the recently developed strategies and progress made on enhancing durability. Finally, insights on the prospects for the future development of stable and practical Rubased OER catalysts are provided.

关键词： OER Ru-based catalysts PEMWE Degradation mechanisms Stabilization strategies

Defect detection of light guide plate based on improved YOLOv5 networks

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Optoelectronics Letters 2024年第9期20卷 560-567页

作者： XIAO ming GONG Yefei wang Hongding LU mingli GAO Hua School of Electrical Engineering Yancheng Institute of TechnologyYancheng 224007China School of Electrical and Automation Engineering Changshu Institute of TechnologyChangshu 215500China School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China Wuxi Novo Automation Technology Corporation Wuxi 214000China

Light guide plate(LGP)is a kind of material used in the backlight *** to improve the quality control of LGP has become the focus of research in the *** address issues such as low gray contrast and a high proportion of small target defects in LGP images,an improved you only look once version 5(YOLOv5)neural network based on multi-scale dilation convolution and a novel loss function is proposed.

关键词： network plate light

Advanced Electrical Motors and Control Strategies for High-quality Servo Systems-A Comprehensive Review

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Chinese Journal of Electrical Engineering 2024年第1期10卷 63-85页

作者： ming Cheng Jiawei Zhou Wei Qian Bo wang Chenchen Zhao Peng Han School of Electrical Engineering Southeast UniversityNanjing 210096China ESTUN Automation Co. Ltd.Nanjing 211106China Ansys Inc.San JoseCA 95134USA

Recent technological advancements have propelled remarkable progress in servo systems,resulting in their extensive utilization across various high-end applications.A comprehensive review of high-quality servo system technologies,focusing specifically on electrical motor topologies and control strategies is *** terms of motor topology,this study outlines the mainstream servo motors used across different periods,as well as the latest theories and technologies surrounding contemporary servo *** terms of control strategies,two well-established approaches are presented:field-oriented control and direct torque ***,it discusses advanced control strategies employed in servo systems,such as model predictive control(MPC)and fault tolerance control,among others.

关键词： Servo system servo motor control strategy magnetic field modulation