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Creep-Resistant Covalent Adaptable Networks with Excellent SelfHealing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1545-1556页

作者： Miao Xie Xiao-Rong Wang zhan-Hua Wang He-Sheng Xia State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan University School of Petrochemical Engineering Liaoning Petrochemical University

Covalent adaptive networks (CANs) are capable of undergoing segment rearrangement after being heated, which endows the materials with excellent self-healing and reprocessing performance, providing an efficient solution to the environment pollution caused by the plastic wastes. The main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance property. In this study, a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate groups. DFT calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state, confirming excellent dynamic property of the benzopyrazole-urea bonds. As verified by the FTIR results, this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer networks. Excellent self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea bonds. Phase separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds, which also makes the elastomers display excellent creep-resistance performance. This hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关键词： Covalent adaptive networks Dynamic covalent bond Self-healing polymer

Functional microfluidics:theory,microfabrication,and applications

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International Journal of Extreme Manufacturing 2024年第3期6卷 140-173页

作者： Mingzhu Xie Ziheng zhan Yinfeng Li Junkai Zhao Ce zhang Zhaolong Wang Zuankai Wang Interdisciplinary Research Center of Low-carbon Technology and Equipment College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082People’s Republic of China Energy Research Institute of Shandong Academy of Sciences Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014People’s Republic of China Qian Xuesen Laboratory of Space Technology China Academy of Space Technology(CAST)Beijing 100094People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHong Kong Special Administrative Region of China 999077People’s Republic of China

Microfluidic devices are composed of microchannels with a diameter ranging from ten to a few hundred ***,quite a small(10-9–10-18l)amount of liquid can be manipulated by such a precise *** the past three decades,significant progress in materials science,microfabrication,and various applications has boosted the development of promising functional microfluidic *** this review,the recent progress on novel microfluidic devices with various functions and applications is ***,the theory and numerical methods for studying the performance of microfluidic devices are briefly ***,materials and fabrication methods of functional microfluidic devices are ***,the recent significant advances in applications of microfluidic devices are highlighted,including heat sinks,clean water production,chemical reactions,sensors,biomedicine,capillaric circuits,wearable electronic devices,and ***,perspectives on the challenges and future developments of functional microfluidic devices are *** review aims to inspire researchers from various fields engineering,materials,chemistry,mathematics,physics,and more—to collaborate and drive forward the development and applications of functional microfluidic devices,specifically for achieving carbon neutrality.

关键词： capillary theory functional devices functional microfluidics

A Self-sensing TSA-actuated Anthropomorphic Robot Hand

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Journal of Bionic Engineering 2024年第3期21卷 1174-1190页

作者： Chanchan Xu Shuai Dong Yifan Ma Jingwei zhan Yucheng Wang Xiaojie Wang Institute of Intelligent Machines Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei230031China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefei230026China Institutes of Physical Science and Information Technology Anhui UniversityHefei230601China

This paper introduces a self-sensing anthropomorphic robot hand driven by Twisted String Actuators(TSAs).The use of TSAs provides several advantages such as muscle-like structures,high transmission ratios,large output forces,high efficiency,compactness,inherent compliance,and the ability to transmit power over ***,conventional sensors used in TSA-actuated robotic hands increase stiffness,mass,volume,and complexity,making feedback control *** address this issue,a novel self-sensing approach is proposed using strain-sensing string based on Conductive Polymer Composite(CPC).By measuring the resistance changes in the strain-sensing string,the bending angle of the robot hand's fingers can be estimated,enabling closed-loop control without external *** developed self-sensing anthropomorphic robot hand comprises a 3D-printed structure with five fingers,a palm,five self-sensing TSAs,and a 3D-printed *** studies validate the self-sensing properties of the TSA and the anthropomorphic robot ***,a real-time Virtual Reality(VR)monitoring system is implemented for visualizing and monitoring the robot hand's movements using its self-sensing *** research contributes valuable insights and advancements to the field of intelligent prosthetics and robotic end grippers.

关键词： Anthropomorphic robot hand Twisted string actuator Self-sensing Conductive polymer composite Virtual reality monitoring

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芯片智能布线方法研究综述

自动化学报 2024年第9期50卷 1671-1703页

作者：周展文卓汉逵中山大学计算机学院广州510006

布线是芯片设计自动化流程中至关重要且特别耗时的一环,直接影响最终产品的面积、成本、功耗、速度和可靠性,研究智能布线算法对提高芯片布线效率和优化芯片布线效果具有重要意义.芯片布线问题是一个多目标、多约束的NP困难问题.即使已... 详细信息

布线是芯片设计自动化流程中至关重要且特别耗时的一环,直接影响最终产品的面积、成本、功耗、速度和可靠性,研究智能布线算法对提高芯片布线效率和优化芯片布线效果具有重要意义.芯片布线问题是一个多目标、多约束的NP困难问题.即使已有几十年的研究历史,目前仍存在大量未突破的问题和空间.随着制造工艺的不断发展,布线规则、约束和目标也持续调整和增加,使得布线选择极其困难.因此,对芯片设计自动化中自动布线的前沿研究进行了全面归纳与分析,以帮助科研人员全面了解该领域的研究进展和方向,助力智能布线算法的研究和发展.具体而言,首先阐述芯片布线的问题背景,然后分别介绍全局布线(Global routing,GR)和详细布线(Detailed routing,DR)的任务定义和目标、过程特点、难点和挑战、评估方法;接着详述和分析各布线方法,重点论述基于规划搜索的布线方法和基于机器学习的布线方法的最新研究成果、优缺点及其应用环节;然后介绍公开数据集和开源布线工具;最后总结现有方法在实际应用中存在的局限性,并对自动布线未来的发展趋势和潜在研究方向进行展望.

关键词：机器学习智能规划强化学习芯片布线全局布线详细布线

Delineating homogeneous domains of fractured rocks using topological manifolds and deep learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2996-3013页

作者： Yongqiang Liu Jianping Chen Fujun Zhou Jiewei zhan Wanglai Xu Jianhua Yan College of Construction Engineering Jilin UniversityChangchun130026China China Railway First Survey and Design Institute Group Co. Ltd.Xi’an710043China College of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

Determining homogeneous domains statistically is helpful for engineering geological modeling and rock mass stability *** this text,a technique that can integrate lithology,geotechnical and structural information is proposed to delineate homogeneous *** technique is then applied to a high and steep slope along a ***,geological and geotechnical domains were described based on lithology,faults,and shear ***,topological manifolds were used to eliminate the incompatibility between orientations and other parameters(*** length and roughness)so that the data concerning various properties of each discontinuity can be matched and characterized in the same Euclidean ***,the influence of implicit combined effect in between parameter sequences on the homogeneous domains could be *** learning technique was employed to quantify abstract features of the characterization images of discontinuity properties,and to assess the similarity of rock mass *** results show that the technique can effectively distinguish structural variations and outperform conventional *** can handle multisource engineering geological information and multiple discontinuity *** technique can also minimize the interference of human factors and delineate homogeneous domains based on orientations or multi-parameter with arbitrary distributions to satisfy different engineering requirements.

关键词： Homogeneous domain Geological domain Geotechnical domain Structural domain Topological manifold Deep learning

Molecular mechanism for the unusual enhancement of the second-step chemiluminescence production from the carcinogenic tetrabromohydroquinone and H2O_(2)

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Journal of Environmental Sciences 2024年第7期141卷 330-342页

作者： Zi-Han Wang Chun-Hua Huang Zhi-Sheng Liu Li Mao Ben-zhan Zhu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environment and Resources University of Chinese Academy of SciencesBeijing 100049China

We have found recently that two-step intrinsic hydroxyl radical(·OH)-dependent chemiluminescence(CL)could be produced by carcinogenic tetrahaloquinone and H_(2)O_(2).However,the first-step CL was too fast to clearly detect the stepwise generation of·OH and CL,and to distinguish the exact dividing point between the first-step and second-step *** we found that,extremely clear two-step intrinsic CL could be produced by the relative slow reaction of tetrabromohydroquinone(TBHQ)with H_(2)O_(2),which was directly dependent on the two-step·OH ***,the second-step,but not the first-step CL production of TBHQ/H_(2)O_(2)(CRET donor)was markedly enhanced by fluorescein(a typical xanthene dye,CRET acceptor)through a unique chemiluminescence resonance energy transfer(CRET)*** novel CRET system of TBHQ/H_(2)O_(2)/fluorescein was successfully applied for the sensitive detection of TBHQ with the detection limit as low as 2.5μmol/*** findings will help to develop more sensitive and highly efficient CL or CRET systems and specific CL sensor to detect the carcinogenic haloquinones,which may have broad environmental applications.

关键词： Two-step chemiluminescence Bromohydroquinone Hydrogen peroxide Hydroxyl radical CRET

Progress of additives for morphology control in organic photovoltaics

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Chinese Chemical Letters 2024年第6期35卷 38-46页

作者： Zhongjie Li Xiangyue Kong Yuhao Liu Huayu Qiu Lingling zhan Shouchun Yin Key Laboratory of Organosilicon Chemistry and Materials Technology of Ministry of Education College of MaterialChemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 311121China

The microstructure of the active layer in organic photovoltaics(OPVs),such as the size of phase separation,purity of the phases,and molecular packing within each phase,plays a crucial role in influencing the behavior of excitons and charge carriers within the active *** is also a key determinant of the photovoltaic performance of the *** the optimization of OPV devices,the use of additives has been demonstrated to be an effective strategy in microstructure control,leading to enhanced ***,the quest for stable and efficient novel additives,along with an exploration and summarization of the mechanisms underlying additive-induced microstructure control,is essential for a better understanding of the developmental trends of high-performance *** this review,we categorize additives based on their chemical structures and discuss their effects on the microstructure of the active layer from both thermodynamic and kinetic ***,we elaborate on the working mechanisms and their impact on the photovoltaic performance of the *** review provides an overview of recent advances in additives for OPVs,offering potential guidance for the future development of additives and further optimization of the active layer in photovoltaic devices.

关键词： Organic photovoltaics Additives Active layer morphology Mechanisms Photovoltaic performances

Coherence phase spectrum analyzer for a randomly fluctuated fractional vortex beam

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Photonics Research 2024年第1期12卷 33-39页

作者： ZHUOYI WANG XINGYUAN LU JIANBO GAO XUECHUN ZHAO QIwen zhan YANGJIAN CAI CHENGLIANG ZHAO School of Physical Science and Technology Soochow UniversitySuzhou 215006China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shandong Provincial Engineering and Technical Center of Light Manipulations&Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan 250358China Shandong Joint Research Center of Light Manipulation Science and Photonics Integrated Chip of East China Normal University and Shandong Normal University East China Normal UniversityShanghai 200241China

Fractional vortex beams exhibit a higher degree of modulation dimensions than conventional vortices,thus inheriting superior anti-turbulent transmission properties through the incorporation of additional coherence ***,aliasing the mixed modes induced by coherence degradation makes the quantitative measurement of the topological charge in fractional vortex beams *** this study,a coherence phase spectrum was introduced,and experimental demonstrations to quantitatively determine the fractional topological charge of partially coherent fractional vortex beams were *** leveraging the four-dimensional measurement of a partially coherent light field,the source coherence function was inversely reconstructed,and fractional topological charges were determined with high precision by extracting the phase spectrum of the coherence ***–Gaussian,elliptical Gaussian,and plane-wave-fraction vortex beams with various degrees of coherence were used to demonstrate measurement *** proposed method is applicable to X-rays and electron *** has potential applications in optical encryption,high-capacity optical communication,and quantum entanglement.

关键词： function fractional vortex

Comparative study of different machine learning models in landslide susceptibility assessment: A case study of Conghua District, Guangzhou, China

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China Geology 2024年第1期7卷 104-115页

作者： Ao zhang Xin-wen Zhao Xing-yuezi Zhao Xiao-zhan Zheng Min Zeng Xuan Huang Pan Wu Tuo Jiang Shi-chang Wang Jun He Yi-yong Li Wuhan Center China Geological SurveyMinistry of Natural Resources(Geosciences Innovation Center of Central South China)Wuhan 430205China Guangzhou Institute of Geological Survey Guangzhou 510080China Hubei Transportation Planning Design Institute Co. LtdWuhan 430050China

Machine learning is currently one of the research hotspots in the field of landslide *** clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District,which is the most prone to landslide disasters in Guangzhou,was selected for landslide susceptibility *** evaluation factors were selected by using correlation analysis and variance expansion factor *** four machine learning methods namely Logistic Regression(LR),Random Forest(RF),Support Vector Machines(SVM),and Extreme Gradient Boosting(XGB),landslide models were *** analysis and evaluation of the model were conducted through statistical indices and receiver operating characteristic(ROC)*** results showed that LR,RF,SVM,and XGB models have good predictive performance for landslide susceptibility,with the area under curve(AUC)values of 0.752,0.965,0.996,and 0.998,*** model had the highest predictive ability,followed by RF model,SVM model,and LR *** frequency ratio(FR)accuracy of LR,RF,SVM,and XGB models was 0.775,0.842,0.759,and 0.822,*** and XGB models were superior to LR and SVM models,indicating that the integrated algorithm has better predictive ability than a single classification algorithm in regional landslide classification problems.

关键词： Landslides susceptibility assessment Machine learning Logistic Regression Random Forest Support Vector Machines XGBoost Assessment model Geological disaster investigation and prevention engineering