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Particuology 2024年第2期85卷 280-295页

作者： Fei Zhang Youyu Lu Shaoyan Zhu Funian han Guanghua wen Ping Tang Zibing Hou College of Materials Science and Engineering Chongqing UniversityChongqing400044China Guizhou Academy of Testing and Analysis Guizhou Academy of SciencesGuiyang550014China

In this work,the formation mechanism of the droplet-to-granule was investigated in detail based on mold powder manufacturing.A specific mathematical model of two-stage spray drying was established to describe droplet and granule motion,heat and mass transfer,and granule morphology during spray ***,the relationships between spray drying parameters(inlet temperature,atomization pres-sure,slurry mass flow rate)and the properties of the drying tower(temperature and velocity fields)and mold powder granules(temperature,evaporation rates,moisture content,and diameter)were simulated and calculated using ANSYS/Fluent *** ensure that the granule size of mold powder was controlled within the ideal range(0.2-0.6 mm)for producing granules with appropriate mechanical and metallurgical properties,the following optimum spray drying parameters were chosen based on the results of the numerical simulation:inlet temperatures,873 K;slurry atomization pressure,1.8 MPa;slurry mass flow rate,0.05 kg *** these parameters,the slurry mass flow rate has the most significant effect on granule size.

关键词： Mold powder slurry Spray drying parameters Mathematical model Numerical simulation Granule sizes

Recent advances in bioinspired vision systems with curved imaging structures

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Rare Metals 2024年第4期43卷 1407-1434页

作者： Ze-Ping He Xun han wen-Qiang Wu Zhang-Sheng Xu Cao-Feng Pan CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing100049China ZJU-hangzhou Global Scientific and Technological Innovation Center School of Micro-Nano ElectronicsZhejiang UniversityHangzhou311200China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen518060China

Limited by the planar imaging structure,the commercial camera needs to introduce additional optical elements to compensate for the curved focal plane to match the planar image *** results in a complex and bulky *** contrast,biological eyes possess a simple and compact structure due to their curved imaging structure that can directly match with the curved focal *** by the structures and functions of biological eyes,curved vision systems not only improve the image quality,but also offer a variety of advanced ***,we review the recent advances in bioinspired vision systems with curved imaging ***,we focus on their applications in implementing different functions of biological eyes,as well as the emerging curved neuromorphic imaging systems that incorporate bioinspired optical and neuromorphic processing *** addition,the challenges and opportunities of bioinspired curved imaging systems are also discussed.

关键词： Bioinspired Curved vision system Compound eye Chambered eye Neuromorphic

3D interlocked all-textile structured triboelectric pressure sensor for accurately measuring epidermal pulse waves in amphibious environments

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Nano Research 2024年第3期17卷 1923-1932页

作者： Shaobo Si Chenchen Sun Yufen Wu Jingjing Li han Wang Yinggang lin Jin Yang Zhong lin Wang Department of Optoelectronic Engineering Key Laboratory of Optoelectronic Technology and Systems Ministry of EducationChongqing UniversityChongqing 400044China College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

The performance degradation and even damage of the e-textiles caused by sweat,water,or submersion during all-weather health monitoring are the main reasons that e-textiles have not been commercialized and routinized so ***,we developed an amphibious,high-performance,air-permeable,and comfortable all-textile triboelectric sensor for continuous and precise measurement of epidermal pulse waves during full-day *** on the principle of preparing gas by acid-base neutralization reaction,a one-piece preparation process of amphibious conductive yarn(ACY)with densely porous structures is *** innovative three-dimensional(3D)interlocking fabric knitted from ACYs(0.6 mm in diameter)and polytetrafluoroethylene yarns exhibit high sensitivity(0.433 V·kPa^(-1)),wide bandwidth(up to 10 Hz),and stability(>30,000 cycles).With these benefits,98.8%agreement was achieved between wrist pulse waves acquired by the sensor and a high-precision laser ***,the polytetrafluoroethylene yarn with good compression resilience provides sufficient mechanical support for the contact separation of the ***,the unique skeletonized design of the 3D interlocking structure can effectively relieve the water pressure on the sensor surface to obtain stable and accurate pulse waves(underwater depth of 5 cm).This achievement represents an important step in improving the practicality of e-textiles and early diagnosis of cardiovascular diseases.

关键词： triboelectric pressure sensor amphibious fabric interlocking fabric pulse wave measurement one-piece preparation method

Review on the plastic instability of medium -Mn steels for identifying the formation mechanisms of Lüders and Portevin -Le Chatelier bands

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1285-1297页

作者： Bin Hu han Sui Qinghua wen Zheng Wang Alexander Gramlich Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Steel Institute RWTH Aachen UniversityIntzestraße 152072 AachenGermany

Plastic instability,including both the discontinuous yielding and stress serrations,has been frequently observed during the tensile deformation of medium-Mn steels(MMnS)and has been intensively studied in recent ***,research results are controversial,and no consensus has been achieved regarding the ***,we first summarize all the possible factors that affect the yielding and flow stress serrations in MMnS,including the morphology and stability of austenite,the feature of the phase interface,and the deformation ***,we propose a universal mechanism to explain the conflicting experimental *** conclude that the discontinuous yielding can be attributed to the lack of mobile dislocation before deformation and the rapid dislocation multiplication at the beginning of plastic ***,the results show that the stress serrations are formed due to the pinning and depinning between dislocations and interstitial atoms in ***-induced martensitic transformation,influenced by the mechanical stability of austenite grain and deformation parameters,should not be the intrinsic cause of plastic ***,it can intensify or weaken the discontinuous yielding and the stress serrations by affecting the mobility and density of dislocations,as well as the interaction between the interstitial atoms and dislocations in austenite grains.

关键词： medium manganese steel discontinuous yielding stress serrations retained austenite dislocations

Impact of scandium and terbium on the mechanical properties,corrosion behavior,and biocompatibility of biodegradable Mg-Zn-Zr-Mn alloys

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Journal of Magnesium and Alloys 2024年第2期12卷 546-572页

作者： Khurram Munir Jixing lin Xian Tong Arne Biesiekierski Yuncang Li Cuie wen School of Engineering RMIT UniversityMelbourneVictoria 3001Australia School and Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027China

Magnesium(Mg)-based bone implants degrade rapidly in the physiological environment of the human body which affects their structural integrity and biocompatibility before adequate bone *** earth elements(REEs)have demonstrated their effectiveness in tailoring the corrosion and mechanical behavior of Mg *** study methodically investigated the impacts of scandium(Sc)and terbium(Tb)in tailoring the corrosion resistance,mechanical properties,and biocompatibility of Mg–0.5Zn–0.35Zr–0.15Mn(MZZM)alloys fabricated via casting and hot *** indicate that addition of Sc and Tb improved the strength of MZZM alloys via grain size reduction and solid solution strengthening *** extruded MZZM–(1–2)Sc–(1–2)Tb(wt.%)alloys exhibit compressive strengths within the range of 336–405 MPa,surpassing the minimum required strength of 200 MPa for bone implants by a significant *** polarization tests revealed low corrosion rates of as–cast MZZM(0.25 mm/y),MZZM–2Tb(0.45 mm/y),MZZM–1Sc–1Tb(0.18 mm/y),and MZZM–1Sc–2Tb(0.64 mm/y),and extruded MZZM(0.17 mm/y),MZZM–1Sc(0.15 mm/y),MZZM-2Sc(0.45 mm/y),MZZM-1Tb(0.17 mm/y),MZZM-2Tb(0.10 mm/y),MZZM–1Sc-1Tb(0.14 mm/y),MZZM-1Sc-2Tb(0.40 mm/y),and MZZM–2Sc–2Tb(0.51 mm/y)alloys,which were found lower compared to corrosion rate of high-purity Mg(~1.0 mm/y)reported in the ***,addition of Sc,or Tb,or Sc and Tb to MZZM alloys did not adversely affect the viability of SaOS2 cells,but enhanced their initial cell attachment,proliferation,and spreading shown via polygonal shapes and *** study emphasizes the benefits of incorporating Sc and Tb elements in MZZM alloys,as they effectively enhance corrosion resistance,mechanical properties,and biocompatibility simultaneously.

关键词： Corrosion property In vitro cytotoxicity Magnesium alloys Mechanical property Rare earth elements

Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation

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Journal of Geriatric Cardiology 2024年第3期21卷 251-314页

作者： Chang-Sheng MA Shu-lin WU Shao-wen LIU Ya-ling han Chinese Society of Cardiology Chinese Medical Association Heart Rhythm Committee of Chinese Society of Biomedical Engineering Beijing Anzhen Hospital Capital Medical University Guandong Provincial People’s Hospital Shanghai First People’s Hospital General Hospital of Northern Theater Command 不详

Atrial fibrillation(AF)is the most common sustained cardiac arrhythmia,significantly impacting patients’quality of life and increasing the risk of death,stroke,heart failure,and *** the past two decades,there have been significant breakthroughs in AF risk prediction and screening,stroke prevention,rhythm control,catheter ablation,and integrated *** this period,the scale,quality,and experience of AF management in China have greatly improved,providing a solid foundation for the development of guidelines for the diagnosis and management of *** further promote standardized AF management,and apply new technologies and concepts to clinical practice in a timely and comprehensive manner,the Chinese Society of Cardiology of the Chinese Medical Association and the Heart Rhythm Committee of the Chinese Society of Biomedical Engineering have jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial *** guidelines have comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2-VASc-60 stroke risk score based on the characteristics of AF in the Asian *** guidelines have also reevaluated the clinical application of AF screening,emphasized the significance of early rhythm control,and highlighted the central role of catheter ablation in rhythm control.

关键词： prevention sustained diagnosis

Coordination of distinctive pesticide adjuvants and atomization nozzles on droplet spectrum evolution for spatial drift reduction

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Chinese Journal of Chemical Engineering 2024年第2期66卷 250-262页

作者： Shidong Xue Jingkun han Xi Xi Zhong Lan Rongfu wen Xuehu Ma State Key Laboratory of Fine Chemicals Liaoning Key Laboratory of Clean Utilization of Chemical ResourcesInstitute of Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 16024China School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong 999077China China Tianchen Engineering Corporation Tianjin 300400China School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China

Pesticide adjuvants,as crop protection products,have been widely used to reduce drift loss and improve utilization efficiency by regulating droplet ***,the coordinated regulation mechanisms of adjuvants and nozzles on droplet spectrum remain ***,we established the relationship between droplet spectrum evolution and liquid atomization by investigating the typical characteristics of droplet diameter distribution near the *** on this,the regulation mechanisms of distinctive pesticide adjuvants on droplet spectrum were clarified,and the corresponding drift reduction performances were quantitively evaluated by wind tunnel *** shows that the droplet diameter firstly shifts to the smaller due to the liquid sheet breakup and then prefers to increase caused by droplet *** the surface tension of sprayed liquid facilitates the uniform liquid breakup and increasing the viscosity inhibits the liquid deformation,which prolong the atomization process and effectively improve the droplet *** a result,the drift losses of flat-fan and hollow cone nozzles are reduced by about 50%after adding organosilicon and vegetable oil *** contrast,the air induction nozzle shows a superior anti-drift ability,regardless of distinctive *** findings provide insights into rational adjuvant design and nozzle selection in the field application.

关键词： Pesticide drift Spray droplets Particle size distribution Spray atomization Transport processes Adjuvants

Cluster DetectionMethod of Endogenous Security Abnormal Attack Behavior in Air Traffic Control Network

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Computers, Materials & Continua 2024年第5期79卷 2523-2546页

作者： Ruchun Jia Jianwei Zhang Yi lin Yunxiang han Feike Yang College of Computer Science Sichuan UniversityChengdu610065China Equipment Management and Unmanned Aerial Vehicle College of Air Force Engineering University Air Force Engineering UniversityXi’an710051China

In order to enhance the accuracy of Air Traffic Control(ATC)cybersecurity attack detection,in this paper,a new clustering detection method is designed for air traffic control network security *** feature set for ATC cybersecurity attacks is constructed by setting the feature states,adding recursive features,and determining the feature *** expected information gain and entropy of the feature data are computed to determine the information gain of the feature data and reduce the interference of similar feature *** autoencoder is introduced into the AI(artificial intelligence)algorithm to encode and decode the characteristics of ATC network security attack behavior to reduce the dimensionality of the ATC network security attack behavior *** on the above processing,an unsupervised learning algorithm for clustering detection of ATC network security attacks is ***,determine the distance between the clustering clusters of ATC network security attack behavior characteristics,calculate the clustering threshold,and construct the initial clustering ***,the new average value of all feature objects in each cluster is recalculated as the new cluster ***,it traverses all objects in a cluster of ATC network security attack behavior feature ***,the cluster detection of ATC network security attack behavior is completed by the computation of objective *** experiment took three groups of experimental attack behavior data sets as the test object,and took the detection rate,false detection rate and recall rate as the test indicators,and selected three similar methods for comparative *** experimental results show that the detection rate of this method is about 98%,the false positive rate is below 1%,and the recall rate is above 97%.Research shows that this method can improve the detection performance of security attacks in air traffic control network.

关键词： Air traffic control network security attack behavior cluster detection behavioral characteristics information gain cluster threshold automatic encoder

Robust reinforcement learning with UUB guarantee for safe motion control of autonomous robots

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Science China(Technological Sciences) 2024年第1期67卷 172-182页

作者： ZhanG RuiXian han YiNing SU Man lin ZeFeng LI HaoWei ZhanG LiXian School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of Management Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Tracking and Telecommunication Technology Beijing 100094China

This paper addresses the issue of safety in reinforcement learning(RL)with disturbances and its application in the safety-constrained motion control of autonomous *** tackle this problem,a robust Lyapunov value function(rLVF)is *** rLVF is obtained by introducing a data-based LVF under the worst-case disturbance of the observed *** the rLVF,a uniformly ultimate boundedness criterion is *** criterion is desired to ensure that the cost function,which serves as a safety criterion,ultimately converges to a range via the policy to be ***,to mitigate the drastic variation of the rLVF caused by differences in states,a smoothing regularization of the rLVF is *** train policies with safety guarantees under the worst disturbances of the observed states,an off-policy robust RL algorithm is *** proposed algorithm is applied to motion control tasks of an autonomous vehicle and a cartpole,which involve external disturbances and variations of the model parameters,*** experimental results demonstrate the effectiveness of the theoretical findings and the advantages of the proposed algorithm in terms of robustness and safety.

关键词： motion control reinforcement learning robustness stability

General synthesis of transition metal nitride arrays by ultrafast flash Joule heating within 500 ms

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Science China Chemistry 2024年第6期67卷 1976-1982页

作者： Peiqi Shen Jiahui Zhao Yanan Gao Yunxiang lin Yuchen han Kun Xu School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China Institutes of Physical Science and Information Technology Center of Free Electron Laser&High Magnetic FieldLeibniz International Joint Research Center of Materials Sciences of Anhui ProvinceAnhui UniversityHefei230601China

Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic ***,the conventional synthetic processes for TMNs suffer from high energy consumption and low production *** this study,a range of TMNs and their hetero-composite arrays were successfully synthesized via an ultrafast flash Joule heating technology within 0.5 *** a proof concept,the nitrides and hetero-composites were applied for the electrocatalytic hydrazine oxidation reaction(HzOR),in which the Co_(4)N/Mo_(16)N_(7)arrays shows the best performance with a geometric current density of 100 mA cm^(-2)at 23 mV(*** hydrogen electrode(RHE)).This work paves a new way for the ultrafast synthesis of TMNs which could meet the ever-increased energy crisis.

关键词： flash Joule heating rapid synthesis transition metal nitrides hydrazine oxidation reaction electrocatalysts

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