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Synthesis of Polyethylenes with In-Chain Isolated Carbonyls from CO_(2)and Ethylene via a Tandem Photoreduction/Polymerization Protocol

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CCS Chemistry 2024年第6期6卷 1591-1599页

作者： Fulin zhou Haojie Dai shan Tang Yongfeng zhou Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240

Aiming at accessing polyethylene-bearing in-chain degradable functionality,copolymerization of carbon dioxide(CO_(2))with ethylene has long been recognized as a significant but highly challenging ***,most trials have resulted in ethylene homopolymerization because of the endothermic property and high energy barriers of CO_(2)insertion during polymer chain *** we report an unprecedented tandem reaction protocol for the synthesis of polyethylenes with in-chain carbonyls from CO_(2)and ethylene by the combination of photocatalytic CO_(2)reduction and palladium-catalyzed coordination/insertion *** protocol provides an easy way to adjust the carbonyl content(from 0.13 to 12 mol%)and insertion selectivity(up to 99%isolated carbonyls)of the polyethylene copolymers,which enables the polymers tomaintain the main properties of highdensity polyethylene and simultaneously endows them with good *** addition,besides apolar polyethylene copolymers,polar-functionalized polyethylenes with in-chain isolated carbonyls can also be synthesized from CO_(2),ethylene and a polar monomer using the same *** believe our present work sheds new light on the synthesis of degradable polyethylenes by employing CO_(2)as a green carbonyl source.

关键词： carbon dioxide coordination polymerization polyethylene photoreduction photodegradation

Multi-population particle swarm optimization algorithm for automatic design of steel frames

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 89-103页

作者： Wenchen shan Jiepeng LIU Yao DING Y.Frank CHEN Junwen zhou Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 610000China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Civil Engineering the Pennsylvania State UniversityMiddletownPA 17057USA

Steel structures are widely used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost ***,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design *** are made to improve the algorithm performances including the constraint-based strategy,piecewise mean learning strategy and multi-population cooperative *** proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design *** related parameter influences on optimization results are *** the representative frame,MPPSO can achieve greater efficiency through reduction of the number of analyses by more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design *** addition,a migration interval of 1 and the number of populations as 5 are recommended to obtain better MPPSO *** purpose of the study is to propose a method with high efficiency and robustness that is not confined to structural scales and design *** aims to provide a reference for automatic structural optimization design problems even with dimensional *** proposed method can be easily generalized to the optimization problem of other structural systems.

关键词： steel frame multi-population particle swarm optimization automatic structural optimization design

Implantable Electrochemical Microsensors for In Vivo Monitoring of Animal Physiological Information

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Nano-Micro Letters 2024年第3期16卷 183-211页

作者： Jin zhou Shenghan zhou Peidi Fan Xunjia Li Yibin ying Jianfeng Ping Yuxiang Pan Laboratory of Agricultural Information Intelligent Sensing College of Biosystems Engineering and Food ScienceZhejiang UniversityHangzhou 310058People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200People’s Republic of China

In vivo monitoring of animal physiological information plays a crucial role in promptly alerting humans to potential diseases in animals and aiding in the exploration of mechanisms underlying human ***,implantable electrochemical microsensors have emerged as a prominent area of *** microsensors not only fulfill the technical requirements for monitoring animal physiological information but also offer an ideal platform for *** have been extensively studied for their ability to monitor animal physiological information in a minimally invasive manner,characterized by their bloodless,painless features,and exceptional *** development of implantable electrochemical microsensors for in vivo monitoring of animal physiological information has witnessed significant scientific and technological advancements through dedicated *** review commenced with a comprehensive discussion of the construction of microsensors,including the materials utilized and the methods employed for *** this,we proceeded to explore the various implantation technologies employed for electrochemical *** addition,a comprehensive overview was provided of the various applications of implantable electrochemical microsensors,specifically in the monitoring of diseases and the investigation of disease ***,a concise conclusion was conducted on the recent advancements and significant obstacles pertaining to the practical implementation of implantable electrochemical microsensors.

关键词： Electrochemical microsensors Implantable sensors In vivo monitoring Animal physiological information

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Cogeneration of Innovative Audio-visual Content: A New Challenge for Computing Art

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Machine Intelligence Research 2024年第1期21卷 4-28页

作者： Mengting Liu ying zhou Yuwei Wu Feng Gao Advanced Institute of Information Technology Peking UniversityHangzhou311215China School of Electronic and Computer Engineering Shenzhen Graduate SchoolPeking UniversityShenzhen 518000China Peng Cheng Laboratory Shenzhen 518000China School of Arts Peking UniversityBeijing 100871China

In recent years,computing art has developed rapidly with the in-depth cross study of artificial intelligence generated con-tent(AIGC)and the main features of ***-visual content generation has gradually been applied to various practical tasks,including video or game score,assisting artists in creation,art education and other aspects,which demonstrates a broad application *** this paper,we introduce innovative achievements in audio-visual content generation from the perspective of visual art genera-tion and auditory art generation based on artificial intelligence(Al).We outline the development tendency of image and music datasets,visual and auditory content modelling,and related automatic generation *** objective and subjective evaluation of generated samples plays an important role in the measurement of algorithm *** provide a cogeneration mechanism of audio-visual content in multimodal tasks from image to music and display the construction of specific stylized *** are still many new op-portunities and challenges in the field of audio-visual synesthesia generation,and we provide a comprehensive discussion on them.

关键词： Artificial intelligence(AI)art audio-visual artificial intelligence generated content(AIGC) multimodal artistic evalu-ation

Carbon-based nanomaterials cause toxicity by oxidative stress to the liver and brain in Sprague-Dawley rats

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Nuclear Science and Techniques 2024年第6期35卷 54-64页

作者： ying-ying Xu Chan Jin Meng Wu Jian-Ye zhou Hui-Ling Wei Department of Gastroenterology China-Japan Friendship HospitalBeijing 100029China shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Institute of Particle and Nuclear Physics College of PhysicsHenan Normal UniversityXinxiang 453007China

Carbon-based nanomaterials have important research significance in various disciplines,such as composite materials,nanoelectronic devices,biosensors,biological imaging,and drug ***,the human and ecological risks associated with carbon-based nanomaterials have received increasing ***,the biological safety of carbon based nanomaterials has not been systematically *** this study,we used different types of carbon materials,namely,graphene oxide(GO),single-walled carbon nanotubes(SWCNTs),and multiwalled carbon nanotubes(MWCNTs),as models to observe their distribution and oxidative damage in *** results of Histopathological and ultrastructural examinations indicated that the liver and lungs were the main accumulation targets of these ***-μ-XRF analysis revealed that SWCNTs and MWCNTs might be present in the *** shows that the three types of carbon-based nanomaterials could cross the gas-blood barrier and eventually reach the liver *** addition,SWCNTs and MWCNTs could cross the blood-brain barrier and accumulate in the cerebral *** increase in ROS and MDA levels and the decrease in GSH,SOD,and CAT levels indicated that the three types of nanomaterials might cause oxidative stress in the *** suggests that direct instillation of these carbon-based nanomaterials into rats could induce ROS *** addition,iron(Fe)contaminants in these nanomaterials were a definite source of free ***,these nanomaterials did not cause obvious damage to the rat brain *** deposition of selenoprotein in the rat brain was found to be related to oxidative stress and Fe *** information may support the development of secure and reasonable applications of the studied carbon-based nanomaterials.

关键词： Carbon-based nanomaterials Oxidative stress Trace element distribution TEM SR-μ-XRF

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Securing Forwarding Layers from Eavesdropping Attacks Using Proactive Approaches

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Computers, Materials & Continua 2024年第4期79卷 563-580页

作者： Jiajun Yan ying zhou Anchen Dai Tao Wang School of Electronics and Communication Engineering Sun Yat-sen UniversityShenzhen518107China

As an emerging network paradigm,the software-defined network(SDN)finds extensive application in areas such as smart grids,the Internet of Things(IoT),and edge *** forwarding layer in software-defined networks is susceptible to eavesdropping *** hopping is amoving target defense(MTD)technology that is frequently employed to resist eavesdropping *** the traditional route hopping technology,both request and reply packets use the same hopping *** an eavesdropping attacker monitors the nodes along this path,the risk of 100%data leakage becomes *** this paper,we present an effective route hopping approach,called two-day different path(TDP),that turns communication paths into untraceable moving *** technology minimizes the probability of data leakage by transmitting request data and reply data through different ***,a brief introduction to the network model and attack model involved in this paper is ***,the algorithm and processingmethod of the TDP are ***,the paper proposes three differentmetrics tomeasure the effectiveness of the proposed ***,theoretical analysis and simulation results show that the TDP can effectively reduce the percentage of data exposure,decrease eavesdropping attack success probability,and improve the unpredictability of the path.

关键词： Route hopping moving target defense software-defined network two-way different path metrics

Solving Multi-Objective Vehicle Routing Problems with Time Windows: A Decomposition-Based Multiform Optimization Approach

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Tsinghua Science and Technology 2024年第2期29卷 305-324页

作者： Yiqiao Cai Zifan Lin Meiqin Cheng Peizhong Liu ying zhou Xiamen Key Laboratory of Data Security and Blockchain Technology College of Computer Science and TechnologyHuaqiao UniversityXiamen361021China College of Engineering Huaqiao UniversityQuanzhou362000China School of Computer Sciences Shenzhen Institute of Information TechnologyShenzhen518000China

In solving multi-objective vehicle routing problems with time windows (MOVRPTW),most existing algorithms focus on the optimization of a single problem formulation. However,little effort has been devoted to exploiting valuable knowledge from the alternate formulations of MOVRPTW for better optimization performance. Aiming at this insufficiency,this study proposes a decomposition-based multi-objective multiform evolutionary algorithm (MMFEA/D),which performs the evolutionary search on multiple alternate formulations of MOVRPTW simultaneously to complement each other. In particular,the main characteristics of MMFEA/D are three folds. First,a multiform construction (MFC) strategy is adopted to construct multiple alternate formulations,each of which is formulated by grouping several adjacent subproblems based on the decomposition of MOVRPTW. Second,a transfer reproduction (TFR) mechanism is designed to generate offspring for each formulation via transferring promising solutions from other formulations,making that the useful traits captured from different formulations can be shared and leveraged to guide the evolutionary search. Third,an adaptive local search (ALS) strategy is developed to invest search effort on different alternate formulations as per their usefulness for MOVRPTW,thus facilitating the efficient allocation of computational resources. Experimental studies have demonstrated the superior performance of MMFEA/D on the classical Solomon instances and the real-world instances.

关键词： MOVRPTW multiform optimization multiform construction knowledge transfer adaptive local search

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

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Chinese Journal of Polymer Science 2024年第6期42卷 693-710页

作者： ying zhou Bai Xue Lan Xie Chang-Mei Wu Qiang Zheng Department of Polymer Materials and Engineering College of Materials and Metallurgy Guizhou University National Engineering Research Center for Compounding and Modification of Polymer Materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State Key Laboratory of Public Big Data Guizhou University Department of Polymer Science and Engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Microano functional filler Polymer composite Electromagnetic interference shielding

Beamline design for multipurpose muon beams at CSNS EMuS

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Nuclear Science and Techniques 2024年第5期35卷 1-12页

作者： Yang Hong ying-Peng Song Lu-Ping zhou Jing-Yu Tang Zhi-Hao zhou Nikolaos Vassilopoulos Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China Radiotherapy Physics and Technology Center Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China Xi’an Jiaotong University Health Science Center Xi’an 710049China Department of Radiation Oncology First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710049China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China

A new muon beam facility,called the Experimental Muon Source(EMuS),was proposed for construction at the China Spallation Neutron Source(CSNS).The design of the complex muon beamlines for the EMuS baseline scheme,which is based on superconducting solenoids,superferric dipoles and room-temperature magnets,is presented *** muon beams,including surface muons,decay muons and low energy muons,have been developed for multipurpose *** optics design and simulation results of the trunk beamline and branch beamlines are *** a proton beam power of 25 kW at a standalone target station that consists of a conical graphite target and high-field superconducting solenoids,the muon beam intensity in the trunk beamline varies from 10^(7)/s for surface muons to 10^(10)/s for high-momentum decay *** at the endstations,these values vary from 10^(5)/s for surface muons to 10^(8)/s for decay muons.

关键词： Surface muons Decay muons Muon beamline Superconducting solenoids Multi-channel electrostatic separator

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