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A numerical method for predicting bursting strength of composite rocket motor case considering filament winding process-induced stress

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Chinese Journal of Aeronautics 2025年第2期38卷 505-518页

作者： Jiqiu LIANG Fei ZHAO Dan WU Anxin DING Hubei Key Laboratory of Advanced Aerospace Propulsion Technology Wuhan 430040China System Design Institute of Hubei Aerospace Technology Academy Wuhan 430040China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed *** method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments with fiber tension are wound layer by layer,and consider the effects of accumulated stress and deformation during filament winding on the bursting strength of composite ***∅520 mm composite cases as a case study,the filament-winding-process-induced stress and deformation as well as progressive damage behavior are numerically predicted,followed by a comparison with experimental *** numerical results show that the predicted bursting pressures for composite cases manufactured on the mandrels with and without a flexible component are 14.20 MPa and 21.40 MPa,*** values exhibit slight deviation from the measured pressures of 13.50 MPa and 21.57 ***,the predicted damage locations,situated respectively in the dome and cylinder,agree well with the experimental *** observations indicate that use of flexible component reduces the load-bearing capacity of the ***,it validates the reliability and accuracy of the proposed numerical method in predicting the bursting strength of composite cases.

关键词： Composite case Fiber tension Bursting strengt hProgressive damage analysis Filament winding

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Insight into slag-enhanced thermal desorption at the organo-mineral interface of clay soils

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Pedosphere 2025年第2期35卷 312-324页

作者： Juan ZHANG Xin WANG Xinyue DU Shukai FAN Hui LIU Minghua ZHANG State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological Engineering University of Science and Technology Beijing State Key Laboratory of Mineral Processing Environmental Engineering InstituteBGRIMM Technology Group Shandong Institute of Geophysical & Geochemical Exploration College of Agricultural and Environmental Sciences University of California

Multiple active components in steel slags can optimize soil texture and catalyze the thermal desorption of refractory organic pollutants,especially polycyclic aromatic hydrocarbons （PAHs）.In this study,a safety and risk assessment was conducted on toxic metals present in collected steel slags,and the refining slag with a high content of free-Ca O from the XG iron and steel plant （XGRS） was selected and used to regulate the plasticity index （PI） of clay *** the clay soil with high liquid limit and high plasticity （CH）,the PI reduced from 34.3% to 24.8% with steel slags at an addition ratio of 10%（mass percent）,and for the clay soil with low liquid limit （CL）,the PI decreased from 22.8% to 16.5%,resulting in silt soil with optimal thermal *** thermal removal efficiency of PAHs in CH decreased from 81.9% to 74.0% at 350°C as the soil water content increased from 0 to 150 g kg-1,due to the hydration and swelling of clay minerals and the heat loss associated with dehydroxylation and *** efficiency further decreased to 68.7% using 2%（mass percent） Ca O as an additive due to the delayed dehydr（oxyl）ation of clay minerals and enhanced aromatization of soil organic *** contrast,addition of 2% high-content titania-bearing slag （HTBS） enhanced the removal efficiency of high-ring PAHs,with the efficiency increasing for 5-ring from 52.6% to 59.7% and for 6-ring from 76.6% to 81.8%.This is due to the presence of amorphous TiO2and crystalline CaTiO3in HTBS,which can degrade water to produce reactive oxygen *** 2% XGRS addition facilitated the complete removal of PAHs by air-supplemented lattice oxygen,leading to the oxidation of C–C bonds in CH to C–O,C=O,and O–C=O functional *** study provides valuable insights into the use of additives to enhance the thermal remediation of PAH-contaminated clay soils via activating oxygen species and oxidizing C–C bonds in organo-mineral complexes within clay soils.

关键词： catalytic degradation clay dehydration origanic pollutants polycyclic aromatic hydrocarbons reactive oxygen species remediation steel slags

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Bottlebrush Random Copolymers at Oil-Oil Interfaces

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Chinese Journal of Chemistry 2025年第2期43卷 139-145页

作者： Yaxin Wang Yunhui Wen Yuzheng Luo Shuailong Li Jiaqiu Luo Shaowei Shi State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China

Oil-in-oil nonaqueous emulsions are of great interest for developing emulsion-templated polymers and encapsulation systems that are incompatible with water-sensitive ***-made amphiphilic block copolymers are by far the most efficient stabilizers for oil-in-oil emulsions while less attention is given to copolymers with more complex ***,we report the stabilization of DMSO-silicone oil interface by bottlebrush random copolymers(BRCPs)containing norbornene backbones with densely grafted poly(methyl methacrylate)(PMMA)and polystyrene(PS)side *** assembly kinetics of BRCPs at the DMSO-silicone oil interface can be divided into three processes,including diffusion,reconfiguration and reorganization,and can be varied by tuning the degree of polymerization of the backbone(NB).Due to the high efficiency of BRCPs in reducing the interfacial tension,when using BRCPs as stabilizers,stable silicone oil-in-DMSO traditional emulsions and high internal phase emulsions(HIPEs)can be successfully obtained,while no stable emulsions can be achieved with linear PMMA-b-PS serving as the *** study,for the first time,underscores the great potential of amphiphilic bottlebrush copolymers in preparing oil-in-oil *** the advances in polymerization strategy,a broad variety of amphiphilic bottlebrush copolymers are expected to be synthesized and applied in the stabilization of nonaqueous biphasic systems.

关键词： Bottlebrush copolymers Oil-oil interfaces|Emulsions Surfactants Assembly dynamics

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Construction of Ni single-atom coordinated with doped N and S elements for mild hydrogenation of methyl acrylate to methyl propionate

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Nano Research 2025年第1期18卷 217-224页

作者： Taolue Sun Chen Jian Gang Wang Hui Zhao Guoliang Zhang Zengxi Li Chunshan Li State Key Laboratory of Mesoscience and Engineering CAS Key Laboratory of Green Process and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Huizhou Institute of Green Energy and Advanced Materials Huizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516081China

Although the nickel-based catalyst is able toexhibit comparative catalytic activity to noble metal formethyl acrylate hydrogenation,it requires strict reactioncondition,which can be improved by regulation ofcoordination *** this study,we constructed akind of Ni single-atom coordinated with N and S(Ni-NSC)through the pyrolysis of organic Ni-based precursors at600℃.The existence and fine structure of Ni single-atom were confirmed by the spherical electron microscopicobservation in combination with the X-ray absorption spectroscopy(XAS)*** addition,the catalytichydrogenation assessment suggested that the as-prepared Ni-NSC catalyst exhibited higher activity and stability than theNi/NSC supported catalyst prepared by incipient wetness impregnation *** remarkable catalytic activity was dueto the high dispersion and density of Ni single-atom and weak adsorption energy of intermediates on these Ni sites.

关键词： methyl acrylate mild hydrogenation Ni single-atom coordination environment adsorption energy

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Ionogel electrolyte based on porous graphitic C3N4 nanosheets for room temperature to 150 ℃ quasi-solid-state lithium batteries

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Journal of Energy Chemistry 2025年第5期104卷 494-504页

作者： Zhaoen Liu Xueao Jiang Jiayin Chen Weijian Liu Long Zhao Yang Lv Zhiyong Li Yan Zhang Xiwen Wang Shiguo Zhang College of Energy Engineering Huanghuai University College of Materials Science and Engineering State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Hunan University School of Chemistry and Chemical Engineering Henan Normal University

Ionogels,generally formed by immobilizing ionic liquids （ILs） with polymer gelators,hold considerable promise as quasi-solid-state electrolytes （QSSEs） for lithium metal batteries （LMBs） due to their high safety and electrode ***,their practical use in high-temperature LMBs suffers from the softened polymer chains of gelator at high temperatures,leading to liquid leakage and severe growth of Li ***,a novel inorganic ionogel （PCNIL） combining lithium salt-containing IL with porous graphitic carbon nitride nanosheets （PCN） is developed through direct physical *** exhibits a superior ionic conductivity (0.75 mS cm-1) at room temperature similar to that of neat IL electrolyte （LiIL） and a Li+transference number （0.56） greatly higher than that of Li-IL （0.20）.Furthermore,PCNIL maintains a temperature-independent shear storage modulus of up to 5 MPa from room temperature to 150℃.Consequently,the Li|PCNIL|Li symmetrical cell demonstrates extended reversible lithium plating/stripping over 1200 h without dendritic *** robust mechanical strength,excellent thermal stability,and electrochemical stability of PCNIL allow Li|PCNIL|LiFePO4cells to operate stably in a wide temperature range of 25–150°C.

关键词： Graphitic carbon nitride High temperature Ionogels Lithium metal batteries Quasi-solid-state electrolytes

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Optimizing the overall performance of Cu–Ni–Si alloy via controllingnanometer-lamellar discontinuous precipitation structure

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International Journal of Minerals,Metallurgy and Materials 2025年第4期32卷 915-924页

作者： Jinyu Liang Guoliang Xie Feixiang Liu Wenli Xue Rui Wang Xinhua Liu Key Laboratory for Advanced Materials Processing(MOE) Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Institute of Materials Genome Engineering Henan Academy of SciencesZhengzhou 450046China

Simultaneously achieving high strength and high electrical conductivity in Cu–Ni–Si alloys pose a significant challenge, which greatly constrains its applications in the electronics industry. This paper offers a new pathway to improve properties, by preparation of nanometer lamellar discontinuous precipitates(DPs) arranged with the approximate same direction through a combination of deformationaging and cold rolling process. The strengthening effect is primarily attributed to nanometer-lamellar DPs strengthening and dislocation strengthening mechanism. The accumulation of dislocations at the interface between nanometer lamellar DPs and matrix during cold deformation process can results in the decrease of dislocation density inside the matrix grains, leading to the acceptably slight reduction of electrical conductivity during cold rolling. The alloy exhibits an electrical conductivity of 45.32%IACS(international annealed copper standard, IACS), a tensile strength of 882.67 MPa, and a yield strength of 811.33 MPa by this method. This study can provide a guidance for the composition and microstructure design of a Cu–Ni–Si alloy in the future, by controlling the morphology and distribution of DPs.

关键词： Cu–Ni–Si alloys discontinuous precipitates nanometer-lamellar strengthening dislocation strengthening

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A Real-Time Junction Temperature Estimating Method for SiC MOSFET Based on the Turn-on Drain-Source Current Oscillation

A Real-Time Junction Temperature Estimating Method for SiC M...

引用

International Conference of Electrical, Electronic and Networked Energy Systems, EENES 2024

作者： Yang, Fengming Liang, Lin Zhang, Ziyang State Key Laboratory of Advanced Electromagnetic Technology Power Electronics and Energy Management Key Laboratory Ministry of Education of China School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan430070 China

ISBN: (纸本)9789819618514

Online junction temperature (Tj) measurement is critical for SiC MOSFET reliability evaluation health management and life prediction. In order to make the tradeoff between availability, simplicity, as well as accuracy, this article demonstrates a real-time junction temperature estimating method by selecting the current oscillation peak of drain source (Ioscpeak) during turn-on transient as a temperature sensitive electrical parameter (TSEP). The theoretical and simulation analysis results show that the Ioscpeak is available to be a TSEP. Then, the model of Ioscpeak and Tj is derived through fitting curve based the experimental results. The voltage and load current dependency of proposed method are also discussed. The experimental results demonstrate that the bus voltage level has a negligible influence to the relationship between the Ioscpeak and the Tj, the value of Ioscpeak is increasing with the increment of current level at the specific temperature. The sensitivity of proposed method has a satisfactory performance of junction temperature estimation. The estimation circuit of proposed method has a simplicity hardware with low cost and easy to be implanted with gate drive of SiC MOSFET. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： MOSFET devices

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A Lightweight YOLO-Based Model in Small Object Detection for UAV Optical Sensors

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IEEE Sensors Journal 2025年第10期25卷 17585-17599页

作者： Sun, Hao-Ran Shi, Bao-Jun Hu, Yun-Long Hebei University of Technology State Key Laboratory of Reliability and Intelligence of Electrical Equipment The Key Laboratory of Advanced Intelligent Protective Equipment Technology Ministry of Education School of Mechanical Engineering Tianjin300401 China

Detecting small objects within extensive remote sensing images captured by unmanned aerial vehicle (UAV) optical sensors is crucial for a variety of military and civilian purposes, but it poses considerable challenges. To address the difficulties associated with the numerous parameters and the high computational requirements of existing object detection models, as well as the inadequate performance in identifying small objects in remote sensing images (RSIs) captured by UAV optical sensors, this paper proposes a lightweight model for small object detection. Firstly, Focal Scalable Intersection over Union Loss (SIoU) loss derived by integrating the concept of Focal loss into the traditional SIoU loss. Secondly, this study utilizes channel attention (CA) and GhostNet to reconstruct the backbone. A layer specifically designed for detecting small objects is incorporated into YOLOv5s utilized a depth residual network neck. Furthermore, this study establishes a small fire dataset and evaluate this model on the small fire, AI-TOD dataset and DOTA dataset. Experimental results show that the proposed model achieves the lightweight goal while maintaining high detection performance for small objects. © 2025 IEEE.

关键词： Optical remote sensing

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An improved efficient adaptive method for large-scale multiexplosives explosion simulations

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Defence technology(防务技术) 2025年第3期45卷 28-47页

作者： Tao Li Cheng Wang Baojun Shi School of Mechanical Engineering Key Laboratory of Advanced Intelligent Protective Equipment TechnologyMinistry of EducationHebei University of TechnologyTianjin300401China State Key Lab of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing 100081China

Shock wave caused by a sudden release of high-energy,such as explosion and blast,usually affects a significant range of *** utilization of a uniform fine mesh to capture sharp shock wave and to obtain precise results is inefficient in terms of computational *** is particularly evident when large-scale fluid field simulations are conducted with significant differences in computational domain *** this work,a variable-domain-size adaptive mesh enlargement(vAME)method is developed based on the proposed adaptive mesh enlargement(AME)method for modeling multi-explosives explosion *** vAME method reduces the division of numerous empty areas or unnecessary computational domains by adaptively suspending enlargement operation in one or two directions,rather than in all directions as in AME method.A series of numerical tests via AME and vAME with varying nonintegral enlargement ratios and different mesh numbers are simulated to verify the efficiency and order of *** estimate of speedup ratio is analyzed for further efficiency *** large-scale near-ground explosion experiments with single/multiple explosives are performed to analyze the shock wave superposition formed by the incident wave,reflected wave,and Mach ***,the vAME method is employed to validate the accuracy,as well as to investigate the performance of the fluid field and shock wave propagation,considering explosive quantities ranging from 1 to 5 while maintaining a constant total *** results show a satisfactory correlation between the overpressure versus time curves for experiments and numerical *** vAME method yields a competitive efficiency,increasing the computational speed to 3.0 and approximately 120,000 times in comparison to AME and the fully fine mesh method,*** indicates that the vAME method reduces the computational cost with minimal impact on the results for such large-scale high-energy release problems with signi

关键词： Large-scale explosion Shock wave Adaptive method Fluid field simulations Efficient method

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Four directional circular optical phased array for uniform two-dimensional beam steering at visible wavelength

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Optics Express 2025年第7期33卷 15954-15963页

作者： Zhang, Qianhan Lian, Daixin Xu, Zixu Zhao, Shi Chen, Jingye Dai, Daoxin Shi, Yaocheng State Key Laboratory for Extreme Photonics and Instrumentation Center for Optical and Electromagnetic Research International Research Center for Advanced Photonics College of Optical Science and Engineering Zhejiang University Hangzhou310058 China

Optical phased arrays (OPAs), owing to their remarkable capacity for rapid and precise beam steering, have emerged as a pivotal technology in various applications such as augmented reality, free-space optical communication, and optical imaging. In this paper, we present a 64-element two-dimensional (2D) circular OPA operating at a visible wavelength of 632.5 nm. To the best of our knowledge, this is the first time that 2D continuous beam steering with pure phase control has been realized at the visible wavelengths. We propose arrowhead antennas to reduce residual energy while maintaining the integrity of the far-field pattern. Furthermore, a four-directional array arrangement has been introduced to expand the field of view and enhance the uniformity of the side lobe suppression ratio (SLSR) at different azimuth angles. The measurement for the fabricated OPA shows 2D beam steering with an elevation angle of 9° and an azimuth angle of 360° with an SLSR of over 3 dB. © 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Antenna phased arrays

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