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The transition to turbulent fluidization in a gas-solid fluidized bed operating from ambient temperature to 1600 °C

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PARTICUOLOGY 2024年第10期93卷 111-124页

作者： Zhang, Qingjin Fu, Liangliang Xu, Guangwen bai, Dingrong Shenyang Univ Chem Technol Key Lab Resources Chem & Mat Minist Educ Shenyang 110142 Peoples R China Shenyang Univ Technol Sch Mat Sci & Engn Shenyang 110142 Peoples R China Ordos Lab Ordos 017010 Peoples R China

Turbulent fluidized bed proves effective in industrial processes due to superior heat and mass transfer and chemical reaction performance. However, understanding the transition to turbulent fluidization remains limited, especially at temperatures exceeding 1000 degrees C, making it challenging to develop hightemperature fluidized bed applications. This paper presents an experimental investigation on the turbulent fluidization onset velocity (Uc), measured in a 30 mm diameter bed using corundum particles with average diameters from 0.68 mm to 1.58 mm in temperatures from ambient to 1600 degrees C. Experimental results reveal that Uc increases with temperature up to 600 degrees C, stabilizes within the 600-1200 degrees C range, and then decreases above 1200 degrees C, demonstrating the varying relative significance of hydrodynamic and interparticle forces at different temperatures. To help design and operate high-temperature applications of turbulent fluidization, we developed Uc correlations based on experimental data from both literature sources and this study, covering temperatures of up to 1600 degrees C and particles of Groups A to D.

关键词： High-temperature fluidized beds Turbulent fluidization Transition velocity Pressure fluctuations Hydrodynamic forces Interparticle forces REGIME TRANSITION HYDRODYNAMICS PRESSURE VELOCITIES SIZE

Primitive functional groups directed distinct photocatalytic performance of imine-linked donor-acceptor covalent organic frameworks

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Nano Research 2024年第6期17卷 4994-5001页

作者： Xitong Ren Jiajie Sun Yusen Li Feng bai Key Laboratory for Special Functional Materials of Ministry of Education National and Local Joint Engineering Research Center for High-Efficiency Display and Lighting TechnologySchool of Materials Science and Engineeringand Collaborative Innovation Center of Nano Functional Materials and ApplicationsHenan UniversityKaifeng 475004China School of Physics and Electronics Henan UniversityKaifeng 475004China

The combination of donor-acceptor(D-A)structures presents a viable strategy for fabricating covalent organic frameworks(COFs)with exceptional photocatalytic ***,the selection of functional groups on donor or acceptor building blocks and their effect on the macroscopic properties of COFs are *** this study,we tactfully synthesized a pair of Py-DBT-COFs from the same pyrene(Py)donor and 4,7-diphenylbenzo[c][1,2,5]thiadiazole(DBT)acceptor cores with distinct primitive functional *** primitive functional groups of building units determine the photocatalytic properties of corresponding ***,Py-C-DBT-COF synthesized from Py-4CHO and DBT-2NH_(2)showcases a splendid H_(2)evolution rate as high as 21,377.7μmol/(g·h)(with 5 wt.%Pt)originating from better charge transfer capacity,which is significantly superior to that of Py-N-DBT-COF constructed from Py-4NH_(2)and *** distinct photocatalytic performances of the two COFs are demonstrated to originate from the different charge separation and transfer *** work supplies a new avenue for optimizing the photocatalytic performance of D-A COFs from the perspective of primitive functional group selections.

关键词： covalent organic frameworks functional group donor-acceptor photocatalysis

Conceptual design and configurations selection of S/H-UAVs based on Q-rung dual hesitant double layer FQFD

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 193-205页

作者： Yang, Dun Liu, Li bai, wencan Tian, Weiyong Beijing Inst Technol Sch Aerosp Engn Beijing 100081 Peoples R China

For the conceptual design phase of Unmanned Aerial Vehicles (UAVs), a process for conceptual design and configuration selection of Solar/Hydrogen powered UAVs (S/H-UAVs) is proposed. The design requirements of S/H-UAVs were analyzed firstly. The proposed process used Fuzzy Quality Function Deployment (FQFD) to establish logical and quantitative standards. Moreover, in order to appropriately describe the hesitancy of experts while making decision, it used Q-Rung Dual Hesitant Fuzzy Sets (QRDHFS) to score the correlationships. In addition, a decisionmaking framework is proposed to perform a logical selection of typical layouts based on defuzzification method and Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS). The present process has been applied for S/H-UAVs. The resulting set of design requirements consists of three categories: Mission Requirements (MRs), Engineering Characteristics (ECs) and Technical Indicators (TIs). Four typical layouts of S/H-UAVs were sorted and determined. The performance of four typical layouts were evaluated and the Strut-Braced Wing (SBW) with external hydrogen storage was selected as the best layout for S/H-UAVs. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics.

关键词： Hybrid powered UAV Conceptual design Strut-braced wing Hybrid powered UAV Conceptual design Q-Rung Dual Hesitant Fuzzy Set(QRDHFS) Quality function deployment Strut-braced wing FUZZY REQUIREMENTS SYSTEM

Eutectic-derived synthesis of hierarchically nanoporous copper for electrochemical actuation and solar steam generation

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Nano Research 2024年第3期17卷 2011-2018页

作者： Qingguo bai Yan Wang Fuquan Tan Zhonghua Zhang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China School of Applied Physics and Materials Wuyi UniversityDongcheng Village 22Jiangmen 529020China School of Materials Science and Engineering University of JinanWest Road of Nan Xinzhuang 336Jinan 250022China

The utilization of nanoporous copper(np-Cu)as a metallic actuator has gained attention in recent years due to its cost-effectiveness in comparison to other precious *** this,the enhancement of np-Cu’s actuation performance remains a challenge due to limitations in its strain amplitude and actuation ***,np-Cu has been deemed as a promising material for solar absorption due to its localized surface plasmon resonance ***,practical applications such as solar steam generators(SSGs)utilizing np-Cu have yet to be *** this study,we present the development of hierarchically nanoporous copper(HNC)through the dealloying of a eutectic Al-Cu *** hierarchical structure of the HNC features a combination of ordered flat channels and randomly distributed continuous nanopores,which work in synergy to improve actuation *** ordered flat channels,with a sub-micron scale,facilitate rapid mass transport of electrolyte ions,while the nano-sized continuous pores,due to their large specific surface area,enhance the induced *** results indicate that the HNC exhibits improved actuation performance,with a two times increase in both strain amplitude and rate in comparison to other reported ***,the HNC,for the first time,showcases excellent solar steam generation capabilities,with an evaporation rate of 1.47 kg·m^(-2)·h^(-1) and a photothermal conversion efficiency of 92%under a light intensity of 1 kW·m^(-2),which rivals that of nanoporous gold and silver *** enhanced actuation performance and newly discovered solar steam generation properties of the HNC are attributed to its hierarchically porous structure.

关键词： eutectic alloy dealloying hierarchically nanoporous copper(HNC) actuation solar steam generation

超短脉冲激光在掺Er^(3+)磷酸盐玻璃中制备光波导的实验研究

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原子与分子物理学报 2024年第4期41卷 121-128页

作者：白晶龙学文太原师范学院物理系晋中030619 太原师范学院计算与应用物理研究所晋中030619 湖南医药学院怀化418000

超短脉冲激光通过非线性吸收调制光学材料折射率提供了一种高效制备集成三维光子器件的途径.掺Er^(3+)磷酸盐玻璃由于其优异的特性以及在1.55μm通信波段附近的发射光谱,成为了集成光学主动增益材料中的研究热点.实验采用重复频率1 kHz... 详细信息

超短脉冲激光通过非线性吸收调制光学材料折射率提供了一种高效制备集成三维光子器件的途径.掺Er^(3+)磷酸盐玻璃由于其优异的特性以及在1.55μm通信波段附近的发射光谱,成为了集成光学主动增益材料中的研究热点.实验采用重复频率1 kHz,中心波长800 nm,脉冲宽度120 fs的钛宝石飞秒激光放大系统作为制备波导的光源,系统研究了加工参数对激光写入形貌、波导形成及光学特性的影响.实验结果表明,在狭缝整形辅助短焦物镜横向刻写条件下,写入脉冲能量为1.8μJ时,光波导可以在写入速度为10μm/s-160μm的较宽范围内形成;写入速度为40μm/s时,光波导写入脉冲能量参数窗口为1.6μJ-2.0μJ;波导写入深度在125μm-200μm范围时,波导横截面对称性较好且折射率修改明显;近场强度测量结果显示所制备波导近场强度分布对称,导光特性良好.通过有限差分法反推波导区域折射率修改分布,结果显示最大折射率修改为Δn=6.6×10^(-4).截断传输损耗测量结果显示所制备波导的传输损耗低至0.91 dB/cm.

关键词：超短脉冲激光光波导掺铒磷酸盐玻璃集成光学

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Anti-saturation fault-tolerant adaptive torsional vibration control with fixed-time prescribed performance for rolling mill main drive system

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Journal of Iron and Steel Research International 2024年第3期31卷 660-669页

作者： Shuang Liu Chen Du Cong Zhang Zhen-hua bai Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan UniversityQinhuangdao 066004HebeiChina National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

An anti-saturation fault-tolerant adaptive torsional vibration control method with fixed-time prescribed performance for the rolling mill main drive system(RMMDS)was investigated,which is affected by control input saturation,actuator faults,sensor measurement errors,and parameter ***,we gave a continuously differentiable saturation function to approximate the control input saturation characteristic of the RMMDS,translating the saturation characteristic into the matched uncertainty and unknown time-varying gain in the ***,an RMMDS mathematical model with unmatched uncertainty and unknown time-varying gain was developed,taking into account the presence of control input saturation,actuator faults,sensor measurement errors,and parameter *** on the established mathematical model,an error transformation model of the roll speed tracking was constructed by the equivalent error transformation *** to the error transformation model,a barrier Lyapunov function and a novel adaptive controller were studied to ensure that the roll speed tracking error always evolves inside a fixed-time asymmetric ***,numerical simulations were performed in Matlab/Simulink to verify the effectiveness and superiority of the proposed control method in suppressing the RMMDS torsional vibration.

关键词： Fixed-time prescribed performance Control input saturation Actuator fault Unknown time-varying gain Adaptive control Asymmetric constraint

The 2024 M_(j) 7.6 Noto Peninsula, Japan earthquake caused by the fluid flow in the crust

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Earthquake Research Advances 2024年第3期4卷 1-6页

作者： Yuzo Ishikawa Ling bai Center for Integrated Research and Education of Natural Hazards Shizuoka UniversityShizuoka422-8529Japan State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China

On January 1, 2024 at 16:10:09 JST, an M_(j) 7.6 earthquake struck the Noto Peninsula in the southern part of the Sea of Japan. This location has been experiencing an earthquake swarm for more than three years. Here, we provide an overview of this earthquake, focusing on the slip distribution of the mainshock and its relationship with the preceding swarm. We also reexamined the source areas of other large earthquakes that occurred around the Sea of Japan in the past and compared them with the Matsushiro earthquake swarm in central Japan from1964 to 1968. The difference between the Matsushiro earthquake swarm and the Noto earthquake swarm is the surrounding stress field. The Matsushiro earthquake swarm was a strike-slip stress field, so the cracks in the crust were oriented vertically. This allowed fluids seeped from the depths to rise and flow out to the surface. On the other hand, the Noto area was a reverse fault stress field. Therefore, the cracks in the earth's crust were oriented horizontally. Fluids flowing underground in deep areas could not rise and spread over a wide area in the horizontal plane. This may have caused a large amount of fluid to accumulate underground, triggering a large earthquake. Although our proposed mechanism does not take into account other complex geological conditions into consideration, it may provide a simple way to explain why the Noto swarm is followed by a large earthquake while other swarms are not.

关键词： The M 7.6 Noto Peninsular earthquake Earthquake swarm Fluid triggering Strike-slip fault Reverse fault

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A Method of Emergency Volunteer Team Internal Participation in Rescue Decision-Making Considering Psychological Behavior

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Journal of Systems Science and Information 2024年第1期12卷 64-80页

作者： Jie bai Shengqun CHEN College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350002China School of Information Engineering Fujian Business UniversityFuzhou 350506China Engineering Research Center of Big Data Analytics for Business Intelligence Fujian Province UniversityFuzhou 350506China

A method for internal participation in rescue decision-making of emergency volunteer teams considering psychological behavior is proposed to address the time sequence of rescue ***,the problem of multi-tasking and multi-operation within the emergency volunteer team is ***,considering that task leaders are influenced by behavioral and psychological factors in the evaluation,the required time for the job is used as a reference point,and the expected time that volunteers can complete the job is used as an attribute *** task leader's prospect satisfaction value for each volunteer is calculated based on prospect theory,and the perceived utility values of disappointment theory and regret theory are calculated to measure the task leader's satisfaction with each ***,a multilayer coded genetic algorithm is used to construct an optimization model for emergency volunteer decision-making with the objective of maximizing the satisfaction ***,the feasibility and effectiveness of this method are illustrated by an example *** result shows that the efficiency of rescue tasks can be improved through decision optimization within the volunteer team.

关键词： emergency volunteers rescue task multi-layer coding genetic algorithm satisfaction value psychological behavior

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Critical state-induced emergence of superior magnetic performances in an iron-based amorphous soft magnetic composite

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Materials Futures 2024年第2期3卷 149-160页

作者： Liliang Shao Rongsheng bai Yanxue Wu jing Zhou Xing Tong Hailong Peng Tao Liang Zongzhen Li Qiaoshi Zeng Bo Zhang Haibo Ke Weihua Wang Songshan Lake Materials Laboratory Dongguan 523808People’s Republic of China Institute of Physics Chinese Academy of SciencesBeijing 100190People’s Republic of China School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 100096People’s Republic of China School of Materials Science and Engineering Central South UniversityChangsha 410083People’s Republic of China Center for High Pressure Science and Technology Advanced Research Shanghai 201203People’s Republic of China Jiangsu JITRI Advanced Energy Materials Research Institute Co. LtdChangzhou 213000People’s Republic of China

Soft magnetic composites(SMCs)play a pivotal role in the development of high-frequency,miniaturization and complex forming of modern ***,they usually suffer from a trade-off between high magnetization and good magnetic softness(high permeability and low core loss).In this work,utilizing the order modulation strategy,a critical state in a FeSiBCCr amorphous soft magnetic composite(ASMC),consisting of massive crystal-like orders(CLOs,∼1 nm in size)with the feature ofα-Fe,is *** critical-state structure endows the amorphous powder with the enhanced ferromagnetic exchange interactions and the optimized magnetic domains with uniform orientation and fewer micro-vortex *** comprehensive soft magnetic properties at high frequency emerge in the ASMC,such as a high saturation magnetization(Ms)of 170 emu g^(-1)and effective permeability(µ_(e))of 65 combined with a core loss(Pcv)as low as 70 mW cm^(-3)(0.01 T,1 MHz).This study provides a new strategy for the development of high-frequency ASMCs,possessing suitable comprehensive soft magnetic performance to match the requirements of the modern magnetic devices used in the third-generation semiconductors and new energy fields.

关键词： amorphous soft magnetic composites critical state soft magnetic property rotating magnetic field annealing magnetic domain