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Chinese Journal of Polymer Science 2015年第7期33卷 1038-1047页

作者： Xi-xian Ke 徐君庭 bin-yang du Zhi-qiang Fan MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science & EngineeringZhejiang University

The hybrid micelles of polystyrene-b-poly（（N-isopropyl acrylamide）-co-（4-vinylbenzyl chloride）） block copolymer（PS-b-P（NIPAM-co-VBC）） with Prussian blue（PB） in the corona were prepared by reaction of pentacyano（4-（dimethylamino）-pyridine）ferrate（Fe-DMAP）-attached PS-b-P（NIPAM-co-VBC） with Fe Cl3. The formation of the PB framework inside the micelles was verified by UV-Vis, FTIR and TGA. The morphology of the hybrid micelles was studied by TEM and compared with that of the neat and Fe-DMAP-attached PS-b-P（NIPAM-co-VBC）. It is found that attachment of Fe-DMAP may change the short rod-like micelles of the neat PS-b-P（NIPAM-co-VBC） into spherical ones and lead to a smaller micelle size. The morphology of the hybrid micelles may be altered or remain unchanged after formation of the PB framework, depending on the chain structure of PS-b-P（NIPAM-co-VBC） and starting concentration. The thermoresponsive behavior of different micelles was studied using DLS. It is observed that attachment of Fe-DMAP can improve the hydrophilicity of the P（NIPAM-co-VBC） block, leading to weaker hysteresis of the micelle size during the heating and cooling cycle. However, the crosslinked PB framework in the micellar corona may result in a more evident hysteresis phenomenon and blur the two-stepwise change of the micellar size with temperature.

关键词： Block copolymer Thermosensitivity Prussian blue Micelle Hybrid

Influence of Different Inorganic Salts on Crystallization-driven Morphological Transformation of PCL-b-PEO Micelles in Aqueous Solutions

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Chinese Journal of Polymer Science 2014年第9期32卷 1128-1138页

作者： Jie-xin yang Wei-na He 徐君庭 bin-yang du Zhi-qiang Fan MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

Different inorganic salts, including NaSCN, NaCl, MgCl2 and Na2SO4, were added into the aqueous solution containing poly（ε-caprolactone）-b-poly（ethylene oxide）（PCL-b-PEO） semicrystalline mieelles. The effects of inorganic salt on the micellar size and morphology were investigated with TEM and DLS. It is found that addition of NaSCN leads to increase of the micellar size, but the micelles remain to be spherical. By contrast, the other three inorganic salts can induce sphere-to-cylinder or sphere-to-lamella transformations of the PCL-b-PEO semicrystalline mieelles. The alteration rate of the micellar size with the time after addition of the inorganic salts decreases in the following order： NazSO4 〉 NaCl ≈ MgCl2〉 NaSCN. These results were interpreted in terms of the ＂salting-out＂ ability of the cations and anions. The anions SO42- and Cl- have a stronger ＂salting-out＂ ability, driving the morphological transformations of the micelles and leading to a rapid change in micellar size. By contrast, SCN- has a weaker salting-out＂ ability. The cations Na＋ and Mg2＋ may associate with the PEO blocks, leading to a ＂salting-out＂ effect as well. However, the ＂salting-out＂ ability of cations is weaker than that of SO42- and Cl- anions, and the ＂salting-out＂ abilities ofNa＋ and Mg2＋ are similar.

关键词： Block copolymer Crystallization Inorganic salt Micelle.

Co-electrolysis of ethylene glycol and carbon dioxide for formate synthesis

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Science China Chemistry 2024年第5期67卷 1539-1544页

作者： Dongfeng du Fusong Kang Shiru yang bin Shao Jingshan Luo Institute of Photoelectronic Thin Film Devices and Technology State Key Laboratory of Photovoltaic Materials and CellsKey Laboratory of Photoelectronic Thin Film Devices and Technology of TianjinMinistry of Education Engineering Research Center of Thin Film Photoelectronic TechnologyNankai UniversityTianjin 300350China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Frontiers Science Center for New Organic Matter Nankai UniversityTianjin 300071China College of Electronic Information and Optical Engineering Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network TechnologyNankai UniversityTianjin 300350China

Co-electrolysis of waste plastics and carbon dioxide(CO_(2)) into value-added chemicals or fuels is a promising pathway for a sustainable society, but efficient and selective conversion remains a challenge. Herein, a gold-mediated nickel hydroxide(Au/Ni(OH)_(2)) is developed to oxidize waste plastic-derived ethylene glycol(EG) into formate. In-situ electrochemical experiments and theoretical results reveal that the introduction of Au favors the redox properties and EG adsorption behavior of Ni(OH)_(2). The Au/Ni(OH)_(2) catalyst shows an excellent formate selectivity of >90% at high current densities of above 100 m A cm^(-2). When coupled with sputtered bismuth(Bi) cathode for CO_(2) reduction, a high formate Faradic efficiency(FE) of 188.2% at 200 m A cm^(-2)and a good formate productivity of 7.33 mmol m^(-2)s^(-1)at 10 A are obtained in a flow cell and a zero-gap membrane electrode assembly(MEA) cell, respectively. This work demonstrates a promising strategy to convert waste plastics and CO_(2) into valuable products.

关键词： waste plastic upcycling ethylene glycol oxidation carbon dioxide reduction electrocatalysis formate synthesis

Thermo-sensitive Microgels Supported Gold Nanoparticles as Temperature-mediated Catalyst

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Chinese Journal of Polymer Science 2019年第3期37卷 235-242页

作者： Xian-Jing Zhou Hai-Peng Lu Ling-Li Kong Dong Zhang Wei Zhang Jing-Jing Nie Jia-Yin Yuan bin-yang du Xin-Ping Wang Department of Chemistry Zhejiang Sci-Tech University Department of Chemistry Zhejiang University Department of Materials and Environmental Chemistry Stockholm University Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science & Engineering Zhejiang University

Microgels with a thermo-sensitive poly(N-isopropylacrylamide)(polyNIPAm) backbone and bis-imidazolium(VIM) ionic cross-links, denoted as poly(NIPAm-co-VIM), were successfully prepared. The as-synthesized ionic microgels were converted to nanoreactors, denoted as Au@PNI MGs, upon generation and immobilization of gold nanoparticles(Au NPs) of 5–8 nm in size into poly(NIPAm-co-VIM). The content of Au NPs in microgels could be regulated by controlling the 1,6-dibromohexane/vinylimidazole molar ratio in the quaternization reaction. The microgel-based nanoreactors were morphologically spherical and uniform in size, and presented reversible thermo-sensitive behavior with volume phase transition temperatures(VPTTs) at 39–40 °C. The Au@PNI MGs were used for the reduction of 4-nitrophenol, of which the catalytic activity could be modulated by temperature.

关键词： Microgel Thermo-sensitive Gold nanoparticle Catalyst

Protein acetylation sites with complex-valued polynomial model

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Frontiers of Computer Science 2024年第3期18卷 217-226页

作者： Wenzheng BAO bin yang School of Information Engineering Xuzhou University of TechnologyXuzhou 221018China School of Information Science and Engineering Zaozhuang UniversityZaozhuang 277160China

Protein acetylation refers to a process of adding acetyl groups(CH3CO-)to lysine residues on protein *** one of the most commonly used protein post-translational modifications,lysine acetylation plays an important role in different *** our study,we developed a humanspecific method which uses a cascade classifier of complexvalued polynomial model(CVPM),combined with sequence and structural feature descriptors to solve the problem of imbalance between positive and negative *** gene expression programming and differential evolution are utilized to search the optimal CVPM *** also made a systematic and comprehensive analysis of the acetylation data and the prediction *** performances of our proposed method are 79.15%in Sp,78.17%in Sn,78.66%in ACC 78.76%in F1,and 0.5733 in MCC,which performs better than other state-of-the-art methods.

关键词： protein acetylation complex-valued polynomial model machine learning

Comprehensive Assessment of STGSA Generated Skeletal Mechanism for the Application in Flame-Wall Interaction and Flame-Flow Interaction

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Journal of Thermal Science 2024年第5期33卷 1946-1960页

作者： YU Chunkan yang bin Institute of Technical Thermodynamics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Center for Combustion Energy Tsinghua UniversityBeijing 100084China

In this study,we conduct a thorough evaluation of the STGSA-generated skeletal mechanism for C_(2)H_4/*** STGSA-reduced mechanisms are taken into account,incorporating basic combustion models such as the homogeneous reactor model,one-dimensional flat premixed flame,and non-premixed counterflow ***,these models are applied to more complex combustion systems,considering factors like flame-flow interaction and flame-wall *** considerations take into account additional physical parameters and processes such as mixing frequency and *** results indicate that the skeletal mechanism adeptly captures the behavior of these complex combustion ***,it is suggested to incorporate strain rate considerations in generating the skeletal mechanism,especially when the combustion system operates under high turbulent intensity.

关键词： Species-Targeted Global Sensitivity Analysis(STGSA) mechanism reduction Partially Stirred Reactor(PaSR) spark ignition Head-on Quenching(HoQ)

Gear walk instability caused by brake-disc friction characteristics

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Chinese Journal of Aeronautics 2024年第2期37卷 343-359页

作者： Xiaoqiong du bin LI Wen CAI Linyin LUO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Engineering University of MichiganAnn Arbor 48109USA AVIC General Huanan Aircraft Industry Co.Ltd. Zhuhai 519040China

A multi-body dynamic rigid-flexible coupling model of landing gear is established to study the gear walk instability caused by the friction characteristics of the brake *** validating the model with the experimental results,the influence of the landing gear structure and braking system parameters on gear walk is further *** the above factors,the slope of the graph for the friction coefficient of the brake disc and the relative velocity of brake stators and rotors is the most influential factor on gear walk *** trajectory analysis verifies that gear walk occurs when the coupling of multiple factors causes the system to exhibit an equivalent negative damping *** consider a more realistic braking case,a back propagation neural network method is employed to describe the nonlinear behavior of the friction coefficient of the brake *** the realistic nonlinear model of the friction coefficient,the maximum error in predicting the braking torque is less than 10%and the effect of the brake disc temperature on gear walk is *** results reveal that a more negative friction slope may contribute to a more severe unstable gear walk,and reducing the braking pressure is an effective approach to avoid gear walk,which provides help for future braking system design.

关键词： Gear walk Friction characteristics of brake disc Brake-induced vibration Negative damping Rigid-flexible coupling Negative slope of braking torque

Distributed collaborative complete coverage path planning based on hybrid strategy

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Journal of Systems Engineering and Electronics 2024年第2期35卷 463-472页

作者： ZHANG Jia du Xin DONG Qichen XIN bin School of Automation Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Autonomous Intelligent Unmanned Systems Beijing Institute of TechnologyBeijing 100081China

Collaborative coverage path planning(CCPP) refers to obtaining the shortest paths passing over all places except obstacles in a certain area or space. A multi-unmanned aerial vehicle(UAV) collaborative CCPP algorithm is proposed for the urban rescue search or military search in outdoor *** to flexible control of small UAVs, it can be considered that all UAVs fly at the same altitude, that is, they perform search tasks on a two-dimensional plane. Based on the agents’ motion characteristics and environmental information, a mathematical model of CCPP problem is established. The minimum time for UAVs to complete the CCPP is the objective function, and complete coverage constraint, no-fly constraint, collision avoidance constraint, and communication constraint are considered. Four motion strategies and two communication strategies are designed. Then a distributed CCPP algorithm is designed based on hybrid strategies. Simulation results compared with patternbased genetic algorithm(PBGA) and random search method show that the proposed method has stronger real-time performance and better scalability and can complete the complete CCPP task more efficiently and stably.

关键词： multi-agent cooperation unmanned aerial vehicles(UAV) distributed algorithm complete coverage path planning(CCPP)

Designing hierarchical structures for innovative cooling textile

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Nano Research 2024年第10期17卷 9202-9224页

作者： Xiran du Jinlei Li bin Zhu Jia Zhu National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210023China School of Sustainable Energy and Resources Nanjing UniversitySuzhou 215163China

The potential of personal cooling technologies in reducing air conditioning energy consumption and enhancing human thermal comfort is *** review focuses on recent advancements in hierarchical structure design for innovative cooling *** with insights into fundamental heat transfer processes between the human body,textile,and the surroundings,we uncover key control *** the advanced hierarchical structure designs enabling effective radiation,sweat evaporation,conduction management,and integration of cold energy sources for realizing effective human body cooling are systematically ***,we explore multifunctional designs beyond cooling,including switchable cooling-heating and ***,we engage in discussions on unifying cooling performance tests and additional multiple requirements to make strides toward practical *** review is anticipated to be a valuable resource,providing the scientific and industrial communities with a quick grasp of past advancements,current challenges,and future directions in achieving effective human body cooling.

关键词： thermal comfort personal cooling textile hierarchical structures

Transfer relation between subgrade frost heave and slab track deformation and vehicle dynamic response in seasonally frozen ground

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第2期25卷 130-146页

作者： Juanjuan REN Junhong du Kaiyao ZHANG bin YAN Jincheng TIAN MOE Key Laboratory of High-speed Railway Engineering Southwest Jiaotong UniversityChengdu610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China School of Civil Engineering Central South UniversityChangsha410075China Airport Planning and Design Institute POWERCHINA Kunming Engineering Corporation LimitedKunming650051China

Subgrade frost heave in seasonally frozen ground can greatly influence the safety and smooth running of high-speed trains and the service performance of track *** this study,we used a static model to:(1)investigate track-subgrade frost heave and develop a dynamic model of vehicle-track-subgrade frost heave;(2)explore the transfer relation between subgrade frost heave and track structure deformation;(3)examine the characteristics of interlayer debonding;(4)study the influence of subgrade frost heave on the dynamic response of vehicles in high-speed railways in seasonally frozen regions.A Fourier series was used to fit the frost heave waveform and simulate the behavior of subgrade uneven frost heave using data collected *** results show:(i)The position of frost heave significantly affects the transfer of deformation to a slab *** largest deformation of the track slab,with the amplitude transfer ratio reaching 20%,was recorded when the frost heave occurred near the joint of the base plate.(ii)At the same frost heave amplitude,long-wave frost heave causes smaller deformation and debonding of the track structure than short-wave frost *** the wavelength range of 10-30 m,the main frequency of the acceleration spectral density was concentrated between 3.5 and 3.7 Hz,with larger frost heave wavelengths producing smaller superposition on the vertical acceleration of the vehicle.(ii)The maximum wheel-rail force occurs when the front bogie passes the frost heave peak,with greater frost heave amplitudes producing greater wheel-rail *** these results,we conclude there is a clear need to control the frost heave deformation of the track to reduce the dynamic response of the vehicle and in turn improve train operatSubgrade frost heave in seasonally frozen ground can greatly influence the safety and smooth running of high-speed trains and the service performance of track *** this study,we used a static model to:(1)investigate track`-subgr

关键词： Slab track Subgrade frost heave Transfer relation Vehicle-track-subgrade coupling Dynamic response