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Phase evolution and mechanical properties of low-activation refractory high-entropy alloy Ti_(1.5)ZrV_(0.5)Ta_(0.5)

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Journal of Materials Science & technology 2024年第7期174卷 145-156页

作者： Yuxiang Chen Ningyu Li Yijie Wang Kang Liu Yongqin Chang Mingyang Li School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi’an Rare Metal Materials Institute co.ltd Xi’an 710016China

A novel low-activation Ti_(1.5)ZrV_(0.5)Ta_(0.5)refractory high-entropy alloy(RHEA)was designed as a potential candidate for nuclear reactor *** room temperature,it had an elongation of 8.4%and a yield strength of 1096 *** phase evolution of this alloy and its effect on properties was *** 400℃,the solid solution bcc 1 transformed into the fcc phase and bcc 2 phase,and theωphase andαphase also *** 600℃,theωphase andαphase disappeared,and the microstructure of the alloy was composed of the fcc phase and bcc 2 *** the temperature was up to 1200℃,the fcc phase and bcc 2 phase re-transformed into solid solution bcc 1 *** precipitation ofωphase andαphase caused a sharp increase in strength and a decrease in ***,the appearance of the fcc phase led to a simultaneous decrease in strength and ductility,due to larger stress concentrations at the fcc/bcc ***,the formation mechanism of each phase in the alloy was discussed in detail.

关键词： Low-activation Refractory high-entropy alloy Phase evolution Phase formation mechanism Strengthening mechanism

A novel method for calculating broadband electrical performance of high-speed aircraft radome under thermo-mechanical-electrical coupling

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Chinese Journal of Aeronautics 2024年第9期37卷 463-474页

作者： Jianmin JI Jianhua REN Xunya JIANG Wei WANG Huilong YU Kai YIN Bo CHEN beijing Institute of Remote Sensing Equipment Beijing 100854China Shanghai Dong Jun Information and technology co.ltd Shanghai 200050China

The electrical performance of radomes on high-speed aircraft can be influenced by the thermal and mechanical loads produced during high-speed flight,which can affect the detection dis-tance and accuracy of the guidance *** paper presents a new method that uses the Finite Difference Time Domain(FDTD)method to calculate the electrical performance of radomes under Thermo-Mechanical-Electrical(TME)*** method can accurately characterize the effects of material dielectric temperature drift and structural deformation on the electrical performance of the radome under flight conditions,enabling high-precision full-wave calculations of the broadband electrical performance of the *** method initiates by utilizing a Finite Element Grid Model(FE-GM)of the radome to sequentially acquire the radome's response temperature field and structural deformation field through thermal and mechanical ***,spatial mapping techniques are developed to accurately incorporate the dielectric temperature drift and structural deformation of the radome into its Yee grid Electromagnetic(EM)simulation model.A verification case was designed to test the proposed method,and the results confirmed its high computational ***,the effectiveness and necessity of the method were further demonstrated by analyzing the electrical performance of a fused silica ceramic radome used on a high-speed aircraft.

关键词： High-speed aircraft Radomes Thermo-Mechanical-Electrical(TME)coupling Finite Difference Time Domain(FDTD)method Spatial mapping

Enhanced mechanical property by introducing bimodal grains structures in Cu-Ta alloys fabricated by mechanical alloying

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Journal of Materials Science & technology 2024年第5期172卷 104-112页

作者： Ningyu Li Yongqin Chang Mingyang Li Yuxiang Chen Xinrui Luo Shichao Pei Fan Yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi’an Rare Metal Materials Institute co.ltd Xi’an 710016China

Dispersion-strengthened copper alloys can achieve ultra-high strength,but usually at the expense of *** this study,a strategy for overcoming strength-ductility tradeoffof Cu alloys is realized through the introduction of bimodal grains ***-Ta alloys with only 0.5 at.%Ta content were successfully prepared by mechanical alloying combined with spark plasm *** samples prepared by one-step and two-step ball milling methods are named as Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ),*** microstructural characterizations revealed that ultra-fine equiaxed grains with uniformly dispersed Ta precipitates were obtained in the Cu-Ta *** strength of 377 MPa for yield strength together with elongation of∼8%was obtained in Cu-Ta(Ⅰ).Bimodal grains structures composed of fine-grain zones and coarse-grain zones were successfully introduced into Cu-Ta(Ⅱ)by a two-step ball milling approach,and both yield strength(463 MPa)and elongation(∼15%)were significantly synergistic *** hardness values of both Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)were almost kept nearly constant with the increase of annealing time,and the softening temperatures of Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)are 1018 and 1013℃,reaching 93.9%and 93.5%T m of pure Cu(1083℃),*** reveals that the Cu-0.5 at.%Ta alloys exhibit excellent thermal stability and exceptional softening *** nanoclusters with semi-coherent structures play an essential role in enhancing the strength and microstructural stability of *** structures are beneficial to the activation of back stress strengthening and the initiation and propagation of microcracks,thus obtaining the extraordinary combination of strength and *** study provides a new way to fabricate dispersion-strengthened Cu alloys with high strength,high elongation,excellent thermal stability and softening resistance,which have potential application value in the field of the future fusion reactor.

关键词： Cu-Ta alloy Mechanical alloying Ta precipitates Bimodal structures Mechanical property

A high-performance lithium anode based on N-doped composite graphene

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Rare Metals 2024年第3期43卷 1030-1036页

作者： Can Jiao Hao-Bo Sun Li Zhang Shang-Qian Zhao Guo-Yao Pang Chun-Rong Zhao Shi-Gang Lu General Research Institute for Nonferrous Metals Beijing100088China China Automotive Battery Research Institute co.ltd Beijing101407China

Lithium(Li)metal is the most promising electrode for next-gene ration rechargeable *** order to push the commercialization of the lithium metal batteries,a kind of nitrogen(N)-doped composite graphene(NCG)adopted as the Li plating host was prepared to regulate Li metal nucleation and suppress dendrite ***,a new kind of sandwich-type composite lithium metal(STCL)electrode was developed to improve its *** STCL electrode can be used as convenient as a piece of Li foil but no dendrite *** a symmetric battery,the STCL electrode cycled for more than 4500 h with the overpotential of less than 40 *** due to the creative design,the STCL promises the Li-S battery with a prolonged cycling lifespan.

关键词： Lithium metal anode Lithiophilic N-doped composite graphene Sandwich-type composite lithium metal electrode

Design and evaluation of a kind of polymer-bonded explosives with improved mechanical sensitivity and thermal properties

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Defence technology（防务技术） 2024年第10期40卷 13-24页

作者： Na Li Weizhe Wang Zhengzheng Zhang Shaohua Jin Lijie Li Changgen Feng Jiaming Gao Yu Chen School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Gansu Yinguang Chemical Industry Group co.ltd Baiyin 730900China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

The emergence of TKX-50,an energetic ionic salt with a high enthalpy of formation and low sensitivity,has opened a new path for the development of high-energetic,insensitive composite ***,due to the poor interfacial binding properties of TKX-50 with conventional binders,there is a lack of effective guidance for the design of TKX-50 based composite *** address the above issues,the interactions between carboxymethyl cellulose acetate butyrate(CMCAB)and other binders with explosives TKX-50/HMX were compared using the molecular dynamics *** on the simulations,TKX-50/HMX/CMCAB-based polymer-bonded explosives(PBXs)were prepared with CMCAB as binder,which displays a high binding energy(Ebind)with TKX-50 and high cohesive energy density(CED),and the effect of TKX-50 content on the performance of PBXs was *** physical properties of PBXs,specifically the morphology,mechanical sensitivity,and thermal conductivity,were analyzed by SEM,sensitivity apparatus,and thermal conductivity meter,*** specific heat capacity(Cp)and non-isothermal decomposition temperature of PBXs were tested by DSC,and then the corresponding thermal kinetic parameters were analyzed to evaluate their thermal *** adiabatic thermal decomposition processes of PBXs were tested using an ARC *** decomposition mechanism and kinetics were also explored to further analyze their thermal stability and thermal safety under adiabatic *** computer code EXPLO5 was used to predict the detonation parameters of *** results showed that CMCAB and TKX-50 displayed favorable interfacial bonding properties,and TKX-50 can be bonded with HMX to form a molding powder with a desirable morphology and safety *** TKX-50 in PBXs effectively improves the mechanical sensitivity and thermal safety of PBX and has a significant effect on the detonation performance of *** research demonstrates a novel method suitable for screening and inv

关键词： CMCAB TKX-50 HMX Interaction Safety

Atmospheric Particulate Matter 2.5(PM_(2.5))Induces Cell Damage and Pruritus in Human Skin

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Biomedical and Environmental Sciences 2024年第2期37卷 216-220页

作者： HE Qiao XUE Wan Ting LI Li YI Fan LING Xiao GUO Miao Miao college of Chemistry and Materials Engineering Beijing Technology and Business UniversityBeijing 100048China China Light Industry cosmetics Key Laboratory Beijing Technology and Business UniversityBeijing 100048China beijing Lan Divine technology co.ltd Beijing 100872China

With the accelerated rate of urbanization in recent years,air pollution has become an environmental problem that requires urgent resolution,almost all of the world’s population exposed to pollution on a daily *** the... 详细信息

关键词： pollution Skin Human

Evaluation of the injection and plugging ability of a novel epoxy resin in cement cracks

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Petroleum Science 2024年第2期21卷 1211-1220页

作者： Guang-Yao Leng Wei Yan Hai-Mu Ye Er-Dong Yao Ji-Bin Duan Zheng-Xian Xu Ke-Pei Li Jing-Ru Zhang Zhong Li State Key Laboratory of Petroleum Resource&Prospecting China University of Petroleum(Beijing)Beijing102249China CNPC Liaohe Oilfield Gas Storage co.ltd Panjin124000LiaoningChina CNOOC Research Institute co. Ltd.Beijing100028China

Sustained casing pressure(SCP)is a crucial issue in the oil and gas production *** resins,exhibiting exceptional compressive strength,ductility,and shear bonding strength,have the potential to form reliable *** injectivity and sealing capacity of the epoxy resin is crucial parameters for the success of shallow remediation *** study aimed to develop and assess a novel solid-free resin sealant as an alternative to Portland cement for mitigating fluid *** investigation evaluated the viscosity,compressive strength,and brittleness index of the epoxy resin sealant,as well as its tangential and normal shear strengths in conjunction with casing *** flow characteristics and sealing abilities of conventional cement and epoxy resin were comparatively analyzed in *** results showed that the application of a viscosity reducer facilitated control over the curing time of the epoxy resin,ranging from 1.5 to 6 h,and reduced the initial viscosity from 865.53 to 118.71 m Pa,*** mechanical properties of the epoxy resin initially increased with a rise in curing agent content before experiencing a minor *** epoxy resin containing 30%curing agent exhibited optimal mechanical *** a 14-day curing period,the epoxy resin's compressive strength reached81.37 MPa,2.12 times higher than that of cement,whereas the elastic modulus of cement was 2.99 times greater than that of the epoxy *** brittleness index of epoxy resin is only 3.42,demonstrating high flexibility and *** tangential and normal shear strengths of the epoxy resin exceeded those of cement by 3.17 and 2.82 times,*** a 0.5 mm-wide crack,the injection pressure of the epoxy resin remained below 0.075 MPa,indicating superior injection and flow ***,the injection pressure of cement surged dramatically to 2.61 MPa within 5 *** breakthrough pressure of0.5 PV epoxy resin reached 7.53 MPa,decreasing the crack's perme

关键词： Sustained casing pressure Epoxy resin sealant Curing agent Viscosity reducer Mechanical properties Crack sealing

coordinated Restoration Method for Electric Buses and Network Reconfigurations in Distribution Systems Under Extreme Events

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 1994-2003页

作者： Bo Zhang Lu Zhang Wei Tang Zhaoqi Wang Chen Wang China Agricultural University Beijing 100083China State Grid Energy Research Institute co.ltd Beijing 102209China State Grid beijing Electric Power Research Institute Beijing 100075China

Distribution systems are facing challenges in serving lifeline loads after extreme *** reconfiguration is a traditional and practical method for power supply restoration,which has strong but inflexible power transfer capabilities influenced by network *** failures of utility power under extreme events will further limit the efficiency of network *** buses(EBs)can be utilized to achieve power supply considering their discharging capabilities as mobile storage ***,the mobility of EBs and the influences of transport systems must be carefully considered to enhance the resilience of distribution *** and EBs are complementary in terms of recovery capabilities and location flexibility,and more important loads can be recovered by the coordination between EBs and network *** paper proposes a coordinated restoration method for EBs and reconfigurations considering the influences of transport *** post-disaster restoration problem is formulated as a bi-level model,in which the network topology is optimized in the upperlevel aiming at maximizing restoration loads through the main grid and EBs,while the traffic paths of all EBs are optimized with the goal of maximizing the restoration loads by the EBs in the lower-level considering time consumption and energy consumption during *** PSO and a genetic algorithm are used to solve the proposed bi-level optimization *** studies are performed to verify the superiority of the proposed method.

关键词： Distribution system electric bus extreme event network reconfiguration restoration transport system

A Loss-model-based Efficiency Optimization control Method for Induction Traction System of High-speed Train under Emergency Self-propelled Mode

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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 227-239页

作者： Yutong Zhu Yaohua Li Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190China University of Chinese Academy of Sciences Beijing 100190China China Academy of Railway Sciences corporation Limited(beijing Zongheng Electromechanical technology co.ltd Beijing 100081 China IEEE

Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results.

关键词： Efficiency optimization Induction motor Loss model control Motor drives Traction system