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Discovery of Late Permian Jianshanzi volcanic rocks in Qinghe valley of northern Liaoning and its geologic significance

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Global Geology 2008年第3期11卷 145-149页

作者： yuejun chen chunlin sun yuewu sun Research Center of Palaeontology ＆ Stratigraphy Jilin University Changchun 130026 China

Jianshanzi volcanic rocks at Qinghe valley in the northern Liaoning were considered belonging to Early Proterozoie Gaojiayu Formation of Liaohe Group, or to Early Cambrian Beidagou Formation of Qinghezhen Group, or Middle-Late Proterozoic Shenjiapu Formation-Complex of Kaiyuan Group-complex. Dating the zircons from the dacite with schistosity is 2 506 Ma in method of U-Pb （SHRIMP）. This evidence indicates the rocks may be referred to Late Permian in age. Discovery of the rocks is significant to re-recognize stratigraphic property of ＂Liaohe Group＂, regional geoteetonie location and revolution of orogenic zone in Qinghe valley of the northern Liaoning.

关键词： Jianshanzi volcanic rocks Liaohe Group Qinghe valley northern Liaoning

Heterogeneous interface enhanced polyurethane/MXene@Fe_(3)O_(4)composite elastomers for electromagnetic wave absorption and thermal conduction

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 728-737页

作者： Xin An Zhaoxu sun Jiahui Shen Jiajia Zheng Aixi sun Xiping Li Shaohua Jiang Yiming chen Key Laboratory of Urban Rail Transit Intelligent Operation and Maintenance Technology&Equipment of Zhejiang Province College of EngineeringZhejiang Normal UniversityJinhua 321004China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China

The development of high-performance functional composites has become a research hotspot in response to the hazards of over-heating and electromagnetic radiation in modern electronic ***,we grew magnetic Fe_(3)O_(4)particles in situ on the MXene layer to obtain an MXene@Fe_(3)O_(4)composite with rich heterogeneous *** to the unique heterostructure and the synergistic effects of multiple electromagnetic wave absorption mechanisms,the composite achieved a minimum reflection loss of-27.14 dB and an effect-ive absorption bandwidth of 2.05 GHz at an absorption thickness of 2 ***,the MXene@Fe_(3)O_(4)composite could be encapsu-lated in thermoplastic polyurethane(TPU)via thermal *** obtained composite elastomer exhibited a strong tensile strength,and its thermal diffusivity was 113%higher than that of pure *** additional mechanical properties and thermal conduction features render this composite elastomer an advanced electromagnetic absorber to adapt to the ever-changing environment for expanding practical applications.

关键词： composite elastomer MXene electromagnetic wave absorption thermal conduction

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： Xia JIANG Yanyan FANG Xianlin ZENG Jian sun Jie chen National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

Unraveling the complex interactions between plasmonic Ag nanoparticles and biomolecules for enhancing molecular chirality

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Science China Chemistry 2025年第2期68卷 543-551页

作者： chen Wang Yunlong Tao Qingqing cheng Dandan Lu Chuang Liu Guizeng Yang Xuehao sun Lichao sun Qingfeng Zhang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China Suzhou Institute of Wuhan University Suzhou 215123China

Plasmonic nanostructures have been widely employed to enhance the chiral light-matter interactions for chirality sensing owing to their intriguing optical ***,a quantitative understanding of the correlation between enhanced molecular chirality and plasmonic properties in plasmonic nanoparticle-molecule complexes remains a challenge yet to be *** we demonstrate the complex interactions between Ag nanoparticles and biomolecules that generate distinct plasmonic circular dichroism signals ranging from UV to visible *** deliberately changing the surface coverage of chiral molecules,the geometry of Ag nanoparticles,and the aggregation states of the complexes,three distinct underlying mechanisms were found to be intertwined and hybridized for enhancing circular dichroism *** further employed the chiral plasmonic nanoparticle-molecule complexes to quantify the enantiomeric purity of cysteine and explore their possible applications in other chiral *** insights gained from this work shed light on the underlying mechanisms dictating the enhanced circular dichroism signals of chiral plasmonic nanoparticle-molecule complexes.

关键词： chiral plasmonics plasmonic circular dichroism nanoparticle-molecule complexes Ag nanoparticles chirality sensing

Can the Environmental Credit Evaluation Policy Alleviate the Overcapacity of Heavily Polluting Enterprises?

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China & World Economy 2025年第1期33卷 162-194页

作者： Chuanwang sun Jiahui chen China Center for Energy Economics Research School of Economics and MOE Key Laboratory of Econometrics Xiamen UniversityChina

Addressing pollution caused by economic development,especially the overcapacity of polluting enterprises,is crucial for promoting sustainable economic *** environmental policies are essential for strengthening environmental constraints on enterprises and enhancing the effectiveness of regulatory *** study focused on the Environmental Credit Evaluation policy by examining its potential to improve capacity utilization and assessing its broader impact on heavily polluting *** constructed a time-varying difference-in-difference-in-differences model using panel data from 965 industrial enterprises from 2009 to *** findings reveal that,in comparison with their non-heavily polluting counterparts,heavily polluting enterprises subject to the policy demonstrated significant improvements in capacity *** polluting enterprises that experienced a substantial increase in financing costs also exhibited a marked reduction in inefficient investment,without negatively affecting innovation investments or output.

关键词： capacity utilization environmental credit evaluation policy time-varying difference-in-ifference-in-differences model heavily polluting enterprises overcapacity

Influence of ecological restoration on regional temperature-vegetation-precipitation dryness index in the middle Yellow River of China

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Journal of Mountain Science 2025年第2期22卷 636-651页

作者： chen Wei GUO Yuxing sun Congjian School of Geographical Science Shanxi Normal UniversityTaiyuan 030031China Research Center for Ecological Environment in the Middle Reaches of the Yellow River Shanxi Normal UniversityTaiyuan 030031China

Drought is an important disaster factor disturbing the stability of the ecosystem in the middle reaches of the Yellow River(YRM).In this study,the spatiotemporal distribution of drought in the YRM from 2000 to 2021 was quantitatively investigated by constructing the TVPDI(Temperature-VegetationPrecipitation Dryness Index),and its driving mechanism was *** results show that:(1)a significant decreasing trend was observed in the regional annual TVPDI of the YRM,while the autumn TVPDI index showed an increasing trend during 2000-2021.(2)Plants are more susceptible to drought during the growing season.(3)Drought in YRM showed significant spatial heterogeneity,and the high gully area in the Loess Plateau and the earth-rocky mountain areas were less affected by drought than other regions.(4)The Structural Equation Model(SEM)indicated that regional soil moisture and vegetation coverage have a direct influence on regional TVPDI *** study has explored the regional differences of drought in different seasons and landforms in the YRM,providing a basis for carrying out targeted seasonal ecological management and refining regional environmental governance,as well as a reference for formulating differentiated ecological restoration and water resource allocation strategies according to local conditions.

关键词： Temperature Vegetation-Precipitation Dryness Index The middle reaches of the Yellow River Seasonal drought Regional drought

Design of energy-saving driving strategy based on proximal policy optimization considering urban transport information

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Control Theory and Technology 2025年第1期23卷 74-90页

作者： Qifang Liu Dazhen sun Haowen chen Dongzi Li Ping Wang Department of Control Science and Engineering Jilin UniversityChangchun130022JilinChina State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun130022JilinChina

Eco-driving has always been an ongoing *** urban driving conditions,traffic regulations,other vehicle behaviors,and special driving scenarios will have a major impact on the energy consumption of autonomous *** a representative algorithm of artificial intelligence,reinforcement learning has the ability to perform well under complex *** paper uses deep reinforcement learning algorithms to design the economical driving strategies of autonomous vehicles in three driving scenarios:driving at signalized intersection under free traffic flow,car-following on ramps,and driving at signalized intersection considering queue *** the above three driving scenarios,the driving strategy proposed in this paper achieves economical driving performance while satisfying the driving scenario requirements.

关键词： Eco-driving strategy Reinforcement learning Signalized intersection Car-following

Decellularized amniotic membrane promotes the anti-inflammatory response of macrophages via PI3K/AKT/HIF-1α pathway

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Chinese Chemical Letters 2025年第1期36卷 403-407页

作者： Xiongbo Song Jinwen Xiao Juan Wu Li sun Long chen Department of Orthopedics Guizhou Provincial People’s HospitalGuiyang 550000China The Lab of Tissue Engineering and Translational Medicine College of MedicineGuizhou UniversityGuiyang 550000China Wuhan Kangchuang Biotechnology Wuhan 430074China

Macrophages undergo dynamic transitions between M1 and M2 states,exerting profound influences on both inflammatory and regenerative *** biocompatible and wound-healing properties of decellularized amniotic membrane(d AM)make it a subject of exploration for its potential impact on the anti-inflammatory response of *** findings unequivocally demonstrate that d AM promotes anti-inflammatory M2 polarization of macrophage,with its cytokine-rich content posited as a potential *** application of RNA sequencing unveils differential gene expression,implicating the hypoxia inducible factor-1α(HIF-1α)signaling pathway in this intricate *** investigation further demonstrates that d AM facilitates anti-inflammatory M2 polarization of macrophage through the upregulation of epidermal growth factor(EGF),which,in turn,activates the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)pathway and stabilizes HIF-1α.This cascade results in a noteworthy augmentation of anti-inflammatory gene *** study significantly contributes to advancing our comprehension of d AM's immunomodulatory role in tissue repair,thereby suggesting promising therapeutic potential.

关键词： Macrophage Decellularized amniotic membrane Anti-inflammatory response Hypoxia inducible factor-1α Epidermal growth factor

Study of spatiotemporal variation and annual emission of CH_(4)in Shaoxing Yangtze River Delta,China,Using a portable CH4 detector on the UAV

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Journal of Environmental Sciences 2025年第5期151卷 140-149页

作者： Xiaobing Pang Qianqian Shang Lang chen Songhua sun Gaosheng Zhao Zhentao Wu Canming Zhao Youhao Lu Qianqian sun Yan Lyu Baozhen Wang College of Environment Zhejiang University of TechnologyHangzhou 310000China Shaoxing Institute of Zhejiang University of Technology Shaoxing 312000China Shaoxing Ecological and Environmental Monitoring Center of Zhejiang Province Shaoxing 312000China School of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China Green Intelligence Environmental School Yangtze Normal UniversityChongqing 408100China

Methane(CH_(4))is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and *** 2022,the CH_(4)concentration was approximately 1.9 ppm,which was 264%of the pre-industrial *** spatiotemporal distribution of CH_(4)was investigated by a portable CH_(4)detector on an unmanned aerial vehicle and electric bicycles in Shaoxing,a city situated in the Yangtze River Delta,*** vertical distribution revealed CH_(4)concentration generally decreased slowly with ***,the inversion condition and low atmospheric boundary layer height(ABLH)leaded to the enhancement of CH_(4)with *** highest CH_(4)concentration(2.2±0.1 ppm,n=1428)was observed in winter and the lowest(2.0±0.2 ppm,n=1530)in *** the daily variation,CH_(4)concentration peaked at 5:00 local time(LT)and reached its lowest level at 14:00 LT,which was attributed to the daily variation of ABLH,lowest in the early morning and highest in the *** urban areas,CH_(4)concentrations showed higher levels near restaurants,natural gas stations and sewerage well,with a maximum value of 13.1 ppm,which was caused by CH_(4)emission and natural gas leakage from these *** annual CH_(4)emission in Shaoxing were estimated to be approximately 69 ton/(km^(2)·year)by the mass balance *** with other cities in the world,the CH_(4)emission is in higher level which imply some control measures should be conducted to reduce CH_(4)emission in Shaoxing.

关键词： Portable CH_(4)detector Spatiotemporal variation Annual CH_(4)emission Unmanned aerial vehicle