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Journal of Materials Science & Technology 2024年第3期170卷 246-254页

作者： Ze pu wang WenHong Ruan MinZhi Rong MingQiu Zhang Key Laboratory for Polymeric Composite and Functional Materials of MOE GD HPPC LabIGCMESchool of ChemistrySun Yat-Sen UniversityGuangzhou 510275China

To tackle the challenge of producing highly filled polymer composites using the traditional injection molding technique,which is characterized by the fairly high melt viscosity that makes mold filling difficult,the authors propose a solution based on dynamic covalent *** demonstrated by the proof-of-concept experiments,the 4-arm starshaped polycaprolactone(PCL)oligomers and microcrystalline cel-lulose(MCC)are crosslinked by the reversible Diels-Alder(DA)*** flowability of the compounds greatly decreases due to the dissociation of the intercomponent DA bonds at the retro-reaction tempera-ture,and the networked architecture is reconstructed during cooling as a result of the forward DA ***,the high-loading MCC fillers are well distributed in the matrix and covalently bonded to the nearby PCL,forming a striking contrast to the control in which linear PCL acts as the *** DA bonds crosslinked biodegradable PCL composites exhibit decent mechanical strength(20.7 MPa)even at the MCC fraction of 65 wt%,which is superior to those(5-12.2 MPa)of the highly filled PCL composites(with filler contents of 50-63.8 wt%)reported so *** proposed approach has sufficient expansibility for the fabrication of the highly filled polymer composites constructed by other types of matrix and fillers.

关键词： Polymer composites Microcrystalline cellulose Polycaprolactone Injection molding Dynamic reversible chemistry

Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

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Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng wang Xiaoqi wang Shuiyuan cheng Jiaxian Zhu Xinyu Zhang Long cheng Kai wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in *** estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research ***,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was ***,priority control routes for VOC emission sources were proposed for different *** VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main *** protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and *** in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in *** addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route

Improving access to urban parks through public transit optimization

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Frontiers of Architectural Research 2024年第3期13卷 575-592页

作者： Ning Xu Kaidan Guan pu wang School of Architecture Southeast UniversityNanjing 210096China Jiangsu Provincial Urban and Rural Digital Technology Engineering Center Nanjing 210096China

This study establishes an evaluation and optimization framework for the public transit network based on social network analysis and a greedy algorithm,aiming to explore a quantitative approach to improving access to urban parks through public transit *** network analysis and the ArcGIS platform are used to build a public transit network model within Nanjing Old City and analyze its overall network structure *** study also focuses on a method to improve the convenience of reaching regional and citylevel parks by public transit by increasing access and connecting points accordingly.A greedy algorithm is introduced to generate an optimized solution for improving public transit accessibility to regional and city-level parks,consequently enhancing their *** major findings include:(1)The greedy algorithm effectively enhances the performance of the public transit network,but its benefits gradually diminish as more stations are added.(2)Strategically adding stations enhances the performance of most public transit access points,creating efficient pathways for other stations to directly reach these access points and enter regional and city-level parks.(3)The optimized public transit network model offers guidance for the planning and layout of regional and city-level *** site selection for new parks should prioritize establishing connections with the“hubs”in the public transit *** proposed optimization of the public transit network in this study is specific to a single type of urban park,but subsequent research could be conducted to extend the optimization of public transit accessibility around more urban public resources.

关键词： Urban parks Social network analysis Accessibility optimization public transit network Greedy algorithm

A new scheme of PM_(2.5)and O_(3) control strategies with the integration of SOM,GA and WRF-CAMx

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Journal of Environmental Sciences 2024年第4期138卷 249-265页

作者： Wenjiao Duan Xiaoqi wang Shuiyuan cheng Ruipeng wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

Previous air pollution control strategies didn’t pay enough attention to regional collaboration and the spatial response sensitivities,resulting in limited control effects in *** study proposed an effective PM_(2.5)and O_(3) control strategy scheme with the integration of Self-Organizing Map(SOM),Genetic Algorithm(GA)and WRF-CAMx,emphasizing regional collaborative control and the strengthening of control in sensitive *** scheme embodies the idea of hierarchical management and spatial-temporally differentiated management,with SOM identifying the collaborative subregions,GA providing the optimized subregion-level priority of precursor emission reductions,and WRF-CAMx providing response sensitivities for grid-level priority of precursor emission *** Beijing-Tianjin-Hebei and the surrounding area(BTHSA,“2+26”cities)as the case study area,the optimized strategy required that regions along Taihang Mountains strengthen the emission reductions of all precursors in PM_(2.5)-dominant seasons,and strengthen VOCs reductions but moderate NOx reductions in O_(3)-dominant *** spatiotemporally differentiated control strategy,without additional emission reduction burdens than the 14th Five-Year Plan proposed,reduced the average annual PM_(2.5)and MDA8 O_(3) concentrations in 28 cities by 3.2%-8.2% and 3.9%-9.7% respectively in comparison with non-differential control strategies,with the most prominent optimization effects occurring in the heavily polluted seasons(6.9%-18.0%for PM_(2.5)and 3.3%-14.2% for MDA8 O_(3),respectively).This study proposed an effective scheme for the collaborative control of PM_(2.5)and O_(3) in BTHSA,and shows important methodological implications for other regions suffering from similar air quality problems.

关键词： PM_(2.5)and O_(3)control SOM GA WRF-CAMx Bionic algorithm Machine learning

PEPFL:A framework for a practical and efficient privacy-preserving federated learning

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Digital Communications and Networks 2024年第2期10卷 355-368页

作者： Yange Chen Baocang wang Hang Jiang pu Duan Yuan Ping Zhiyong Hong State Key Laboratory of Integrated Service Networks Xidian UniversityXi'an710071China School of Information Engineering Xuchang UniversityXuchang461000China School of Telecommunications Engineering Xidian UniversityXi'an710071China Secure Collaborative Intelligence Laboratory Ant GroupHangzhou310000China Facility of Intelligence Manufacture Wuyi UniversityJiangmen529020China

As an emerging joint learning model,federated learning is a promising way to combine model parameters of different users for training and inference without collecting users’original ***,a practical and efficient solution has not been established in previous work due to the absence of efficient matrix computation and cryptography schemes in the privacy-preserving federated learning model,especially in partially homomorphic *** this paper,we propose a Practical and Efficient Privacy-preserving Federated Learning(PEPFL)***,we present a lifted distributed ElGamal cryptosystem for federated learning,which can solve the multi-key problem in federated ***,we develop a Practical Partially Single Instruction Multiple Data(PSIMD)parallelism scheme that can encode a plaintext matrix into single plaintext for encryption,improving the encryption efficiency and reducing the communication cost in partially homomorphic *** addition,based on the Convolutional Neural Network(CNN)and the designed cryptosystem,a novel privacy-preserving federated learning framework is designed by using Momentum Gradient Descent(MGD).Finally,we evaluate the security and performance of *** experiment results demonstrate that the scheme is practicable,effective,and secure with low communication and computation costs.

关键词： Federated learning Partially single instruction multiple data Momentum gradient descent ElGamal Multi-key Homomorphic encryption

Recent progress in functional modification and crosslinking of bioprosthetic heart valves

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Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： cheng Zheng Li Yang Yunbing wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high *** valve replacement surgery has been recognized as golden standard for the treatment of *** to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of ***,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune *** prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of *** this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis

Molecular mechanisms underlying the negative effects of transient heatwaves on crop fertility

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Plant Communications 2024年第9期5卷 101-115页

作者： Qian Yao Ping Li Xin wang Shuhua Liao pu wang Shoubing Huang College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China

Transient heatwaves occurring more frequently as the climate warms,yet their impacts on crop yield are severely underestimated and even *** lasting only a few days or even hours during sensitive stages,such as microgametogenesis and flowering,can significantly reduce crop yield by disrupting plant *** advances in multi-omics and GWAS analysis have shed light on the specific organs(e.g.,pollen,lodicule,style),key metabolic pathways(sugar and reactive oxygen species metabolism,Ca2+homeostasis),and essential genes that are involved in crop responses to transient heatwaves during sensitive *** review therefore places particular emphasis on heat-sensitive stages,with pollen development,floret opening,pollination,and fertilization as the central narrative *** multifaceted effects of transient heatwaves and their molecular basis are systematically reviewed,with a focus on key structures such as the lodicule and tapetum.A number of heat-tolerance genes associated with these processes have been identified in major crops like maize and *** mechanisms and key heat-tolerance genes shared among different stages may facilitate the more precise improvement of heat-tolerant crops.

关键词： heat stress floret fertility pollen pollen tube growth seed set molecular mechanism

A new targeted on-ramp control approach considering both efficiency and equity

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Transportation Safety and Environment 2024年第3期6卷 85-95页

作者： Shengnan Li Minglun Li Jianjun Dai pu wang School of Traffic and Transportation Engineering Central South UniversityChangsha 410075HunanChina Hunan Communications Research Institute Co. LtdChangsha 410015HunanChina

On-ramp control is an effective approach for alleviating traffic congestion on ***,there is still a lack of on-ramp control approaches applicable to large regional highway ***,we develop a targeted on-ramp control approach applicable to regional highway networks by taking advantage of the vehicle source information,which pinpoints the on-ramps contributing major traffic flow to the highway ***,a combined and tunable controlling index is proposed to enhance the equity of the generated traffic control *** proposed on-ramp control approach is validated on an actual large highway network using actual travel demand *** indicate that the proposed approach can well mitigate the traffic congestion of highway bottleneck while at the same time enhancing the equity and practicability of the generated traffic control scheme.

关键词： on-ramp control vehicle source traffic congestion equity

Scattering for the Radial Schrodinger Equation with Combined Power-type and Choquard-type Nonlinearities

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1029-1041页

作者： Ying wang cheng Bin XU The Graduate School of China Academy of Engineering Physics Beijing 100088P.R.China School of Mathematics and Statistics Qinghai Normal UniversityXining 810008P.R.China

In this paper,we show the scattering of the radial solution for the nonlinear Schrodinger equation with combined power-type and Choquard-type nonlinearities iut+△u=λ1|u|p1-1u+λ2(Iα*|u|^(p2))|u|p^(2-2)*** the energy space H^(1)(R^(N))forλ_(1)λ_(2)=-*** establish a scattering criterion for radial solution together with Morawetz estimate which implies the scattering *** show that the defocusing perturbation terms does not determine the scattering solution in energy space.

关键词： Schrodinger equation Choquard-type Scattering theory

Improvement of the Subcooling Problem of Sodium Acetate Trihydrate by a Combination of Stirring or Internal Electric Field and Nucleating Agent

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Journal of Thermal Science 2024年第6期33卷 2235-2244页

作者： wang Chuang wang Suyaola LIU Pengcheng cheng Xingxing wang Zhiqiang School of Energy and Power Engineering Shandong University National Engineering Laboratory for Reducing Emissions from Coal Combustion

Energy storage devices are the hub of a multi-energy complementary distributed energy *** salts are the most suitable phase change material for energy storage devices,but subcooling is the main obstacle to their *** requires a driving force so the use of nucleating agents alone does not reduce subcooling to a very low *** address this issue,this paper first screened nucleating agents and then further reduced the subcooling of sodium acetate trihydrate in conjunction with stirring or direct *** effects of rotor mass,rotational speed,direct current voltage,and electrode material on nucleation were ***,the stability of the composite phase change material in the presence of simultaneous stirring and energization was *** results showed that the addition of 1.5% in weight of disodium hydrogen phosphate dodecahydrate to sodium acetate trihydrate can reduce the subcooling to about 2.3℃.Continued addition of stirring or electricity can reduce the subcooling of sodium acetate trihydrate to within 0.5℃ or even eliminate *** higher the momentum of the stirring,the better the improvement in subcooling,phase separation,and thermal *** higher the direct current voltage,the better the nucleation effect,but the electrode life will be *** silver electrode has the best nucleation *** new material was produced in the solution after 100 cycles in the presence of both stirring and direct *** melting point of the phase change material was increased by 0.2℃ and the latent heat value decreased by 1.8%,still with good *** trace of deionized water should be added to the phase change material in subsequent studies to compensate for the consumption of water by the anodic elution.

关键词： internal electric field phase change material sodium acetate trihydrate stirring subcooling