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Facile Control of Molecular weight Distribution via Droplet-Flow Light-Driven Reversible-Deactivation Radical Polymerization

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Chinese Journal of Chemistry 2022年第19期40卷 2305-2312页

作者： yang Zhou yangkang Fu Mao Chen Department of Macromolecular Science State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai200438 China

Molecular weight distribution(MwD)is fundamental for polymer analysis,which influences many important properties of polymeric *** this work,we demonstrate the development of a computer-aided droplet-flow system that combines photo-mediated reversible-deactivation radical polymerization(RDRP)and chain transfer agent(CTA)diffusion strategy to enable facile MwD control for the first *** advantages of this photo-flow polymerization allow controlled chain-growth to yield a variety of polymers of tunable MwDs in a broad range(Ð≈1.1—1.9)with predetermined molecular weights(Mn≈4—30 kDa)and good chain-end ***,the computer-aided platform has streamlined an automatic and high-throughput pathway to prepare polymer libraries of tunable *** copolymers,chemical compositions could be readily regulated besides MwDs with the droplet-flow *** believe that this work should be attractive for polymer engineering,and informative to create more flow polymerization techniques toward on-demand control of diverse polymer characters.

关键词： Photocatalysis Copolymerization Synthetic methods Molecular weight distribution Flow chemistry

Ionothermal Synthesis, Structure, Thermal Properties and Magnetic Behaviors of a Novel Dinuclear Copper(Ⅱ) Coordination Compound

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Chinese Journal of Structural Chemistry 2020年第5期39卷 978-982页

作者： ZHAO Xiao-yang Department of Environmental Engineering Henan Polytechnic InstituteNanyang 473009China

A novel dinuclear copper(Ⅱ)coordination compound,[CuⅡ(Hpdc)(phen)Cl][CuⅡ(pdc)(phen)]·4 H2 O(1,H2 pdc=pyridine-2,6-dicarboxylic acid,phen=1,10-phenanthroline),has been obtained by an ionothermal method using the ionic liquid 3-butyl-1-methylimidazolium bromide([Bmim]Br)as solvent,and fully characterized by elemental analyses,energy-dispersive X-ray spectroscopy(EDX),IR and single-crystal X-ray diffraction.1 belongs to the triclinic system,space group■with a=11.406(4),b=11.801(5),c=16.093(6)?,α=106.124(6)°,β=113.480(7)°,γ=93.853(7)°,Z=2,V=1942.3(13)?3,Dc=1.570 g·cm-3,F(000)=928,μ=1.235 mm-1,the final R=0.0588,wR=0.1369 and S=*** compound exhibits a two-dimensional layered structure constructed by[CuⅡ(Hpdc)(phen)Cl]and[CuⅡ(pdc)(phen)]fragments via the hydrogen bonds andπ-πstacking *** addition,its thermal properties and magnetic behaviors were also studied in *** magnetic properties revealed that there is a ferromagnetic interaction between Cu…Cu in 1.

关键词： ionothermal dinuclear π-πstacking interactions thermal properties magnetic behaviors

Electromagnetic chirality:from fundamentals to nontraditional chiroptical phenomena

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Light(Science & Applications) 2020年第1期9卷 550-567页

作者： Jungho Mun Minkyung Kim Younghwan yang Trevon Badloe Jincheng Ni yang Chen Cheng-wei Qiu Junsuk Rho Department of Chemical Engineering Pohang University of Science and TechnologyPohang 37673Korea Department of Mechanical Engineering Pohang University of Science and TechnologyPohang 37673Korea Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore

Chirality arises universally across many different *** advancements in artificial nanomaterials have demonstrated chiroptical responses that far exceed those found in natural *** phenomena are complicated processes that involve transitions between states with opposite parities,and solid interpretations of these observations are yet to be clearly *** this review,we present a comprehensive overview of the theoretical aspects of chirality in light,nanostructures,and nanosystems and their chiroptical *** of observed chiroptical phenomena based on these fundamentals are intensively *** start with the strong intrinsic and extrinsic chirality in plasmonic nanoparticle systems,followed by enantioselective sensing and optical manipulation,and then conclude with orbital angular momentum-dependent *** review will be helpful for understanding the mechanisms behind chiroptical phenomena based on underlying chiral properties and useful for interpreting chiroptical systems for further studies.

关键词： materials interpreting momentum

Cross-Layer QoS Enabled SDN-Like Publish/Subscribe Communication Infrastructure for IoT

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China Communications 2020年第3期17卷 149-167页

作者： Yulong Shi yang Zhang Junliang Chen State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

Publish/subscribe paradigm is often adopted to create the communication infrastructure of the Internet of Things(IoT)for many clients to access enormous real-time sensor ***,most current publish/subscribe middlewares are based on traditional ossified IP networks,which are difficult to enable Quality of Service(QoS).How to design the next generation publish/subscribe middleware has become an urgent *** emerging Software Defined Networking(SDN)provides new opportunities to improve the QoS of publish/subscribe facilities for delivering events in IoT owing to its customized programmability and centralized *** can encode event topics,priorities and security policies into flow entries of SDN-enabled switches to satisfy personalized QoS *** this paper,we propose a cross-layer QoS enabled SDN-like publish/subscribe communication infrastructure,aiming at building an IoT platform to seamlessly connect IoT services with SDN networks and improving the QoS of delivering *** first present an SDN-like topic-oriented publish/subscribe middleware architecture with a cross-layer QoS control *** we discuss prototype implementation,including topic management,topology maintenance,event routing and policy *** the end,we use differentiated services and cross-layer access control as cross-layer QoS scenarios to verify the *** results show that our middleware is effective.

关键词： IoT publish/subscribe software defined networking quality of service middleware

HYBRID CONTROL OF HYDRAULIC PRESS MACHINE BASED ON ROBUST CONTROL

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Chinese Journal of Mechanical Engineering 2008年第2期21卷 72-76页

作者： FANG Yu yang Jian CHAI Xiaodong School of Urban Railway Transportation Shanghai University of Engineering Science Shanghai 201620 China

A robust control algorithm is proposed to focus on the non-linearity and variables of the hydraulic press machine with the proportional vatve. The proposed robust controller does not need to design stable compensator in advance, which is simple in design and has large scope of uncertainty applications. The feedback gains of the proposed robust controller are small, so it is easily implemented in engineering applications. The theoretical and experimental research on the position and speed control of the hydraulic press machine is carried out. The control requirements of the hydraulic press machine during the working process are met in the position and speed at the same time. Experimental results show that the proposed controller has better robustness subject to load variables and adaptability of parameter variations of the hydraulic press machine with the proportional valve.

关键词： Robust control Hydraulic press machine Position and speed control

Influence of Electric Current on Kirkendall Diffusion of Zn/Cu Couples

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Journal of Materials Science & Technology 2008年第3期24卷 410-414页

作者： Yingju LI Yuansheng yang Xiaohui FENG Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The influence of electric current on Kirkendall diffusion in Zn/Cu couples was investigated. Under the action of different electric currents, the Zn/Cu diffusion couples were annealed at 785℃ for different holding time. The experimental results show that the displacement of the Kirkendall plane increases with increasing holding time. However, the displacement of the Kirkendall plane with electric current is larger than that without electric current. The relationship between the displacement of the Kirkendall plane and the holding time is changed under the action of electric current. The likely reason for the electric current enhancing effect is the energy transfer from electron to jumping atom, increasing the integrated diffusion coefficient, which leads to the increase in the velocity of Kirkendall plane.

关键词： Electric current Electromigration Kirkendall effect Darken equations

Urban Agglomeration Formation and Its Spatiotemporal Expansion Process in China: From the Perspective of Industrial Evolution

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Chinese Geographical Science 2020年第3期30卷 532-543页

作者： NIU Fangqu yang Xinyu wANG Fang Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Col-laborative Innovation Center for Geopolitical Setting of Southwest China and Borderland Development Kunming 650500China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China School of Public Administration Inner Mongolia UniversityHohhot 010070China

Urban agglomeration research has received increasing attention in China’s national development strategies, and has become a hot topic in academic research. This study develops a theoretical framework that explores the formation mechanism and expansion process of urban agglomerations from the perspective of industrial evolution, and identifies the development issues and their causes by taking yangtze Delta and Beijing-Tianjin-Hebei urban agglomerations as case studies. In the process of urban agglomeration formation within a free market, as has happened in yangtze Delta region, the central city develops first, its secondary industry is then transferred to its neighboring cities, and the work division and cooperation with the neighboring cities is gradually established. However, in the 1990 s, aiming to become an international metropolis, Beijing implemented a series of administrative policies to encourage the reduction of the secondary industry and the development of the tertiary industry, before its secondary industry were fully developed and transferred to its neighboring cities. This delayed the integration process and the development of the Beijing-Tianjin-Hebei urban agglomeration. This study builds a good foundation for the construction of the theoretical system’s urban agglomeration study, and provides references for decision making in an urban agglomeration development.

关键词： urban agglomeration expansion mechanism industry Beijing-Tianjin-Hebei yangtze Delta

Influence of the Compacts Homogeneity on the Incidence of Cracks during Thermal Debinding in Ceramic Injection Molding

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Journal of Materials Science & Technology 2009年第2期25卷 264-268页

作者： Xianfeng yang Zhipeng Xie Yong Huang State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

During thermal debinding in ceramic injection molding, the inhomogeneity of green body is a key origin of cracks. In this study, the impact of low molecular weight binders on the homogeneity of the green body was investigated. Incidence of cracks during thermal debinding indicated that the volume ratio of wax to stearic acid should be out of high viscosity and incompletely wetting region. In these two formulation regions, typical inhomogeneous microstructures were observed. By mercury intrusion method, it was shown that pore size distribution of the debinded compacts was determined by thermal degradation of low molecular weight binders. A particle-rich region model was established to predict the nucleation of cracks caused by solid loading fluctuation. The criterion of cracks nucleation was that local capillary force from solid loading fluctuation was larger than the suction force from the surroundings.

关键词： Ceramic injection molding Cracks Debinding Homogeneity

Multi-Sinusoidal waveform Shaping for Integrated Data and Energy Transfer in Aging Channels

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China Communications 2023年第4期20卷 243-258页

作者： Jie Hu Yaping Hou Kun yang yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Integrated data and energy transfer(IDET)is capable of simultaneously delivering on-demand data and energy to low-power Internet of Everything(Io E)*** propose a multi-carrier IDET transceiver relying on superposition waveforms consisting of multi-sinusoidal signals for wireless energy transfer(wET)and orthogonal-frequency-divisionmultiplexing(OFDM)signals for wireless data transfer(wDT).The outdated channel state information(CSI)in aging channels is employed by the transmitter to shape IDET *** the constraints of transmission power and wDT requirement,the amplitudes and phases of the IDET waveform at the transmitter and the power splitter at the receiver are jointly optimised for maximising the average directcurrent(DC)among a limited number of transmission frames with the existence of carrier-frequencyoffset(CFO).For the amplitude optimisation,the original non-convex problem can be transformed into a reversed geometric programming problem,then it can be effectively solved with existing *** for the phase optimisation,the artificial bee colony(ABC)algorithm is invoked in order to deal with the *** between the amplitude optimisation and phase optimisation yields our joint *** results demonstrate the advantage of our joint design for the IDET waveform shaping with the existence of the CFO and the outdated CSI.

关键词： integrated data and energy transfer(IDET) wireless energy transfer(wET) simultaneous wireless information and power transfer(SwIPT) carrier-frequency-offset(CFO) waveform aging channels outdated channel state information(CSI) orthogonal frequency division multiplexing(OFDM)