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Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang zhong Jiang Pei-Da Hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

Salt-assisted vapor-liquid-solid growth of high-quality ultrathin nickel oxide flakes for artificial synapses in image recognition applications

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Nano Research 2024年第5期17卷 4622-4630页

作者： hui Zhang Zongjie Shen Alei Li Lin Wang Qinan Wang Yunfei Li Yunlei {1. Juntong Zhu Yong Zhang Mengjiao Han Dan Tian Chun Zhao Lixing Kang Qingwen Li School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China Division of Advanced Materials Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China College of Energy Soochow Institute for Energy and Materials Innovationsand Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhou 215123China Songshan Lake Materials Laboratory Dongguan 523808China School of Advanced Technology Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forest ResourcesNanjing Forestry UniversityNanjing 210037China

Transition metal oxides have attracted intense interest owing to their abundant physical and chemical *** controlled preparation of large-area,high-quality two-dimensional crystals is essential for revealing their inherent properties and realizing high-performance ***,fabricating two-dimensional(2D)transition metal oxides using a general approach still presents substantial ***,we successfully achieve highly crystalline nickel oxide(NiO)flakes with a thickness as thin as 3.3 nm through the salt-assisted vapor-liquid-solid(VLS)growth method,which demonstrated exceptional stability under ambient *** explore the great potential of the NiO crystal in this work,an artificial synapse based on the NiO-flake resistive switching(RS)layer is ***-term and long-term synaptic behaviors are obtained with external *** artificial synaptic performance provides the foundation of the neuromorphic application,including handwriting number recognition based on artificial neuron network(ANN)and the virtually unsupervised learning capability based on generative adversarial network(GAN).This pioneering work not only paves new paths for the synthesis of 2D oxides in the future but also demonstrates the substantial potential of oxides in the field of neuromorphic computing.

关键词： nickel oxide(NiO)flakes vapor-liquid-solid(VLS)growth memristor synapse generative adversarial network(GAN)

Anomalous response to creep deformation from dislocation density during electrically assisted creep aging

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Rare Metals 2024年第10期43卷 5268-5283页

作者： Chang Zhou Li-Hua Zhan Chun-hui Liu Ming-hui Huang College of Mechanical and Electrical Engineering Central South University Light Alloys Research Institute State Key Laboratory of Precision Manufacturing for Extreme Service PerformanceCentral South University

Adding numerous dislocations into metallic materials before the forming stage significantly enhances their deformability. However, this beneficial effect of dislocation defects may not have a simple monotonic relationship with increased dislocation density during electroplastic deformation. This is due to the complex interactions among the drifting electrons, dislocations and solute atoms. This study explores the effect of diverse initial dislocation densities on creep deformation during electrically aided creep aging of an aluminum–lithium alloy. Surprisingly, we discovered a threshold value for the dislocation density that affects electroplastic creep, i.e., an enhanced effect from dislocations weakens when exceeding this density threshold(an anomalous response to creep). Microstructural data also reveal that such an anomalous response originates mainly from differences in various dislocation density-tailored configurations, which can influence the dislocation motions and precipitation kinetics of the strengthening T1.recipitates under the same action of pulsed currents. This study provides important insights into the dislocation density-mediated electroplastic creep of an aluminum–lithium alloy.

关键词： Al–Cu–Li alloy Creep aging Dislocation density Pulsed currents

Carbon nanotube films with ultrahigh thermal-shock and thermalshock-fatigue resistance characterized by ultra-fast ascending shock testing

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Nano Research 2024年第8期17卷 6777-6784页

作者： Mingquan Zhu Shijun Wang Yunxiang Bai Feng Gao Zhenxing Zhu Congying Wang Peng Zhang Hao Jin hui Zhang Luqi Liu Zhiping Xu Xinghong Zhang Fei Wei {1. Zhang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Center for Composite Materials and StructuresHarbin Institute of TechnologyHarbin 150001China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China

The exploration of material failure behavior not only involves defining its limits and underlying mechanisms but also entails devising strategies for improvement and protection in extreme ***'ve pioneered an advanced multi-scale,high-speed ascending thermal shock testing platform capable of inducing unprecedented heat shocks at rates surpassing 1.5℃/*** meticulous examination of the thermal shock responses of carbon nanotube(CNT)films,we've achieved remarkable *** employing an innovative macro-scale synchronous tightening and relaxing approach,we've attained a critical temperature differential in CNT films that exceeds an exceptional 2500℃—surpassing any previously reported metric for highperformance,thermal-shock-resistant ***,these samples have demonstrated exceptional resilience,retaining virtually unchanged strength even after enduring 1.,000 thermal shock cycles at temperatures exceeding 1.00℃.Furthermore,our research has revealed a novel thermal shock/fatigue failure mechanism that fundamentally diverges from conventional theories centered on thermal stress.

关键词： carbon nanotubes failure behavior thermal shock characterization

Sulfonated carbon dots modified IrO_(2)nanosheet as durable and high-efficient electrocatalyst for boosting acidic oxygen evolution reaction

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Nano Research 2024年第9期17卷 8017-8024页

作者： Mengjie Ma Wenxiang Zhu Fan Liao Kui Yin hui Huang Kun Feng Dongdong Gao Jinxin Chen Zenan Li Jun {1. Lai Xu Yang Liu Mingwang Shao Zhenhui Kang Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering(MIMSE) Macao University of Science and TechnologyTaipaMacao 999078China

Oxygen evolution reaction(OER)plays a crucial role in developing energy conversion and adjusting electronic structure of the electrocatalysts can effectively improve the catalytic activity and ***,it is a challenge to adjust the electronic structure on two-dimensional iridium dioxide nanosheets(IrO_(2)NS),which have the advantages of high atom ***,we regulate the surface properties of IrO_(2)NS through sulfonated carbon dots(SCDs)to promote the OER catalytic *** catalyst IrO_(2)NS/SCDs-2 exhibited excellent catalytic activity with a lower overpotential of 1.0 mV than IrO_(2)NS(230 mV)at the current density of 1. mA·cm^(-2)in a 0.5 M H_(2)SO_(4) *** after 1.0 h of stability testing,the overpotential of IrO_(2)NS/SCDs-2 only decreased by 4 ***,transient potential scanning test can visually demonstrate that the addition of SCDs improves the conductivity of the catalyst and increases the electron transfer rate.

关键词： sulfonated carbon dots oxygen evolution reaction electrocatalysis transient potential scanning

Process design and intensification of multicomponent azeotropes special distillation separation via molecular simulation and system optimization

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Chinese Journal of Chemical Engineering 2024年第7期71卷 24-44页

作者： Chunliang Liu Jianhui {1. Ranran Wei Jiuxu Ruan Kaicong Wang Zhaoyou Zhu Yinglong Wang Limei {1. College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China

This work provides an overview of distillation processes,including process design for different distillation processes,selection of entrainers for special distillation processes,system integration and intensification of distillation processes,optimization of process parameters for distillation processes and recent research progress in dynamic control ***,the feasibility of using thermodynamic topological theories such as residual curve,phase equilibrium line and distillation boundary line to analyze different separation regions is discussed,and the rationality of distillation process design is discussed by using its ***,the application of molecular simulation methods such as molecular dynamics simulation and quantum chemical calculation in the screening of entrainer is discussed for the extractive distillation *** thermal coupling mechanism of different distillation processes is used to explore the process of different process ***,a mixed integer nonlinear optimization strategy for the distillation process based on different algorithms is ***,the improvement of dynamic control strategies for different distillation processes in recent years is *** work focuses on the application of process intensification and system optimization in the design of distillation process,and analyzes the challenges,prospects,and development trends of distillation technology in the separation of multicomponent azeotropes.

关键词： Azeotrope separation Process design Optimization algorithm Process integration Dynamic control Entrainer selection

Preparing lipid nanoparticles with tunable drug loading capacity and morphology via improved sequential nanoprecipitation

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Science China Chemistry 2024年第5期67卷 1373-1374页

作者： Haoran Wang Ben zhong Tang Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction Department of Chemistry.Institute of Molecular Functional MaterialsState Key Laboratory of NeuroscienceDivision of Biomedical Engineering and Division of Life ScienceThe Hong Kong University of Science and TechnologyHong Kong 999077China School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Shenzhen 518172China

Nanotechnology hailed as a revolutionary new technology of the 21.t century, has ignited a wave of innovation across diverse fields spanning chemistry, physics, materials science,medicine, engineering, and electronics. In 201., Nature published an article titled “The nanolight revolution is coming”, underscoring that “virus-sized particles that emit light in every color could transform applications ranging from television displays to cancer treatment”.

关键词： sized loading treatment

Effects and mechanisms of Helicobacter pylori infection on the occurrence of extra-gastric tumors

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World Journal of Gastroenterology 2024年第37期30卷 4090-4103页

作者： Shi-Qing Zhao hui-Ling Zheng Xiao-Tian {1. Zi-Ye Wang Yi Su Yan-Yan Shi Research Center of Clinical Epidemiology Peking University Third HospitalBeijing 100191China Health Science Center Peking UniversityBeijing 100191China Department of Gastroenterology Peking University Third HospitalBeijing 100191China

Helicobacter pylori(***)colonizes the human stomach and many studies have discussed the mechanisms of *** infection leading to gastric diseases,including gastric ***,increasing data have shown that the infection of *** may contribute to the development of extra-gastric diseases and ***,systemic immune responses,microbiome disorders,and hypergastrinemia caused by *** infection are associated with many extra-gastric *** review highlights recent discoveries;discusses the relationship between *** and various extra-gastric tumors,such as colorectal cancer,lung cancer,cholangiocarcinoma,and gallbladder carcinoma;and explores the mechanisms of extra-gastric carcinogenesis by ***,these findings refine our understanding of the pathogenic processes of ***,provide guidance for the clinical treatment and management of ***-related extra-gastric tumors,and help improve prognosis.

关键词： Helicobacter pylori Extra-gastric tumors Immune system response Mucosal barrier Gut microbiome

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无人飞行器在不确定扰动下的动态目标跟踪

Engineering 2024年第4期35卷 74-85页

作者： Yanjie Chen Yangning Wu Limin Lan Hang zhong Zhiqiang Miao {1. Zhang Yaonan Wang School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China Department of Computer Science Aberystwyth UniversityAberystwyth SY233DBUK School of Robotics Hunan UniversityChangsha 410082China College of Electrical and Information Engineering Hunan UniversityChangsha 410082China National Engineering Research Center of Robot Visual Perception and Control Technology Hunan UniversityChangsha 410082China

This study proposes an image-based visual servoing(IBVS)method based on a velocity observer for an unmanned aerial vehicle(UAV)for tracking a dynamic target in Global Positioning System(GPS)-denied *** proposed method derives the simplified and decoupled image dynamics of underactuated UAVs using a constructed virtual camera and then considers the uncertainties caused by the unpredictable rotations and velocities of the dynamic target.A novel image depth model that extends the IBVS method to track a rotating target with arbitrary orientations is *** depth model ensures image feature accuracy and image trajectory smoothness in rotating target *** relative velocities of the UAV and the dynamic target are estimated using the proposed velocity *** to the velocity observer,translational velocity measurements are not required,and the control chatter caused by noise-containing measurements is *** integral-based filter is proposed to compensate for unpredictable environmental disturbances in order to improve the antidisturbance *** stability of the velocity observer and IBVS controller is analyzed using the Lyapunov *** simulations and multistage experiments are conducted to illustrate the tracking stability,anti-disturbance ability,and tracking robustness of the proposed method with a dynamic rotating target.

关键词： Unmanned aerial vehicle Visual servoing Velocity observer Target tracking