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Interannual evolution of the chemical composition,sources and processes of PM_(2.5)in Chengdu,china:Insights from observations in four winters

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Journal of Environmental Sciences 2024年第4期138卷 32-45页

作者： Junke Zhang Jiaqi Li Yunfei Su Chunying Chen Luyao Chen Xiaojuan Huang Fangzheng Wang Yawen Huang Gehui Wang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Department of Environmental Science&Engineering Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3)Fudan UniversityShanghai 200438China key lab of Geographic Information Science of the ministry of education School of Geographic SciencesEast China Normal UniversityShanghai 200241China

The air quality in china has improved significantly in the last decade and,correspondingly,the characteristics of PM_(2.5)have also *** studied the interannual variation of PM_(2.5)in Chengdu,one of the most heavily polluted megacities in southwest china,during the most polluted season(winter).Our results show that the mass concentrations of PM_(2.5)decreased significantly year-by-year,from 195.8±91.0μg/m~3in winter 2016 to 96.1±39.3μg/m^(3)in winter *** mass concentrations of organic matter(OM),SO_()4^(2-),NH_(4)^(+)and NO_(3)^(-)decreased by 49.6%,57.1%,49.7% and 28.7%,*** differential reduction in the concentrations of chemical components increased the contributions from secondary organic carbon and NO_(3)^(-)and there was a larger contribution from mobile *** contribution of OM and NO_(3)^(-)not only increased with increasing levels of pollution,but also increased year-by-year at the same level of *** sources of PM_(2.5)were identified:combustion sources,vehicular emissions,dust and secondary *** aerosols made the highest contribution and increased year-by-year,from 40.6%in winter 2016 to 46.3% in winter *** contrast,the contribution from combustion sources decreased from 14.4% to 8.7%.Our results show the effectiveness of earlier pollution reduction policies and emphasizes that priority should be given to key pollutants(e.g.,OM and NO_(3)^(-))and sources(secondary aerosols and vehicular emissions)in future policies for the reduction of pollution in Chengdu during the winter months.

关键词： PM_(2.5) Chemical composition Sources Interannual evolution Winter Chengdu

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Ship recognition based on HRRP via multi-scale sparse preserving method

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Journal of Systems Engineering and Electronics 2024年第3期35卷 599-608页

作者： YANG Xueling ZHANG Gong SONG Hu College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China key lab of Radar Imaging and Microwave Photonics Ministry of EducationNanjing 210016China Nanjing Marine Radar Institute Nanjing 210016China

In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) based on the maximum margin criterion(MMC) is proposed for recognizing the class of ship targets utilizing the high-resolution range profile(HRRP). Multi-scale fusion is introduced to capture the local and detailed information in small-scale features, and the global and contour information in large-scale features, offering help to extract the edge information from sea clutter and further improving the target recognition accuracy. The proposed method can maximally preserve the multi-scale fusion sparse of data and maximize the class separability in the reduced dimensionality by reproducing kernel Hilbert space. Experimental results on the measured radar data show that the proposed method can effectively extract the features of ship target from sea clutter, further reduce the feature dimensionality, and improve target recognition performance.

关键词： ship target recognition high-resolution range profile(HRRP) multi-scale fusion kernel sparse preserving projection(MSFKSPP) feature extraction dimensionality reduction

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The 2^(nd)Asian Conference on Porphyrins,Phthalocyanines and Related Materials

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Chinese Chemical Letters 2024年第7期35卷 1-3页

作者： Gaojie Zhu Zhen Yang Shijun Li Weihua Zhu Rui Cao Junlong Zhang Jianzhang Zhao Jonathan L.Sessler Xunjin Zhu Jianxin Song Yongshu Xie Jianzhuang Jiang key laboratory for Advanced Materials and Institute of Fine Chemicals School of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghai 200237China College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China School of chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013China key laboratory of Applied Surface and colloid chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi'an 710119China Beijing National laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State key laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China Department of chemistry The University of TexasAustinTexas 78712-1224United States Department of chemistry and Institute of Advanced Materials Hong Kong Baptist UniversityHong Kong 999077China key laboratory of Chemical Biology and Traditional Chinese Medicine(ministry of educational of china) Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China

In the past decades,porphyrins,phthalocyanines and related materials have attracted significant attention due to their diverse and brilliant structures[1,2],as well as their unique electronic structures and photophysi... 详细信息

关键词： cyanine phthalocyanine Porphyrin

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A Novel Foreign Object Detection Method in Transmission Lines Based on Improved YOLOv8n

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Computers, Materials & Continua 2024年第4期79卷 1263-1279页

作者： Yakui Liu Xing Jiang Ruikang Xu Yihao Cui Chenhui Yu Jingqi Yang Jishuai Zhou School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao266520China State key laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an710049China key lab of Industrial Fluid Energy Conservation and Pollution Control Qingdao University of TechnologyMinistry of EducationQingdao266520China

The rapid pace of urban development has resulted in the widespread presence of construction equipment andincreasingly complex conditions in transmission corridors. These conditions pose a serious threat to the safeoperation of the power *** vision technology, particularly object recognition technology, has beenwidelyemployed to identify foreign objects in transmission line images. Despite its wide application, the technique faceslimitations due to the complex environmental background and other auxiliary factors. To address these challenges,this study introduces an improved YOLOv8n. The traditional stepwise convolution and pooling layers are replacedwith a spatial-depth convolution (SPD-Conv) module, aiming to improve the algorithm’s efficacy in recognizinglow-resolution and small-size objects. The algorithm’s feature extraction network is improved by using a LargeSelective Kernel (LSK) attention mechanism, which enhances the ability to extract relevant features. Additionally,the SIoU Loss function is used instead of the Complete Intersection over Union (CIoU) Loss to facilitate fasterconvergence of the algorithm. Through experimental verification, the improved YOLOv8n model achieves adetection accuracy of 88.8% on the test set. The recognition accuracy of cranes is improved by 2.9%, which isa significant enhancement compared to the unimproved algorithm. This improvement effectively enhances theaccuracy of recognizing foreign objects on transmission lines and proves the effectiveness of the new algorithm.

关键词： YOLOv8n data enhancement attention mechanism SPD-Conv Smoothed Intersection over Union(SIoU)Loss

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Hi-Tag:a simple and efficient method for identifying protein-mediated long-range chromatin interactions with low cell numbers

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Science china(Life Sciences) 2024年第5期67卷 1027-1034页

作者： Xiaolong Qi Lu Zhang Qiulin Zhao Peng Zhou Sai Xian Zhang Jingjin Li Zhuqing Zheng Yue Xiang Xueting Dai Zhe Jin Yaobang Jian Xinyun Li Liangliang Fu Shuhong Zhao key lab of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education and Key Laboratory of Swine Genetics and Breeding of Ministry of AgricultureCollege of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China The Cooperative Innovation Center for Sustainable Pig Production Wuhan 430070China Hubei Hongshan laboratory Frontiers Science Center for Animal Breeding and Sustainable ProductionWuhan 430070China

Protein-mediated chromatin interactions can be revealed by coupling proximity-based ligation with chromatin ***,these techniques require complex experimental procedures and millions of cells per experiment,which limits their widespread application in life science ***,we develop a novel method,Hi-Tag,that identifies high-resolution,long-range chromatin interactions through transposase tagmentation and chromatin proximity ligation(with a phosphorothioate-modified linker).Hi-Tag can be implemented using as few as 100,000 cells,involving simple experimental procedures that can be completed within 1.5 ***,Hi-Tag is capable of using its own data to identify the binding sites of specific proteins,based on which,it can acquire accurate interaction *** results suggest that Hi-Tag has great potential for advancing chromatin interaction studies,particularly in the context of limited cell availability.

关键词： Hi-Tag chromatin interactions transposase tagmentation chromatin proximity ligation low cell numbers

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Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

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Nano Research 2024年第6期17卷 4916-4923页

作者： Yuanxi Liu Wenjie Xu Shichao Xu Haifeng Wu Baoli Zhang Li Song Zhen-Gang Wang State key laboratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Ministry of Education)Beijing Laboratory of Biomedical MaterialsCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China National Synchrotron Radiation laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China

Reconstructing enzymatic active sites presents a significant challenge due to the intricacies involved in achieving enzyme-like scaffold folding and spatial arrangement of essential functional *** is also a growing interest in building biocatalytic networks,wherein multiple enzymatic active sites are localized within a single artificial system,allowing for cascaded *** this work,we report the self-assembly of imidazole or its derivatives with fluorenylmethyloxycarbonyl-modified histidine and Cu2+to fabricate a supramolecular catalyst,which possesses catechol oxidase-like dicopper center with multiple imidazole as the coordination *** electron microscopy,low-temperature X-band continuous-wave electron paramagnetic resonance,K-edge X-ray absorption spectra/the extended X-ray absorption fine structure analysis,and density functional theory modeling were used for the structural characterization of the *** phenol derivatives and the dissolved oxygen were used as the substrates,with the addition of 4-aminoantipyrine to generate a red adduct with a maximum absorbance at 510 nm,for obtaining time-dependent absorbance change curves and estimating the *** results reveal that the addition of imidazole synergistically accelerates the oxidative activity about 10-fold and the hydrolysis activity about 14-fold than fluorenylmethyloxycarbonyl modified-histidine/Cu2+.The supramolecular nanoassembly also exhibits the ability to catalyze oxidation/hydrolysis cascade reactions,converting 2′,7′-dichlorofluorescin diacetate into 2′,7′-*** process can be regulated through the methylation of the imidazole component at various *** work may contribute to the design of advanced biomimetic catalysts,and shed light on early structural models of the active sites of the primitive copper-dependent enzymes.

关键词： enzyme mimic self-assembly supramolecular catalyst cascade reactions

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Excess Activity Tuned by Distorted Tetrahedron in CoMoO_(4) for Oxygen Evolution

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Energy & Environmental Materials 2024年第1期7卷 247-252页

作者： Hengbo Xiao Kai Chi Hongxia Yin Xiangji Zhou Pengxiang Lei Peizhi Liu Jiakun Fang Xiuhong Li Songliu Yuan Zhen Zhang Yaqiong Su Junjie Guo Lihua Qian School of Physics Huazhong University of Science and TechnologyWuhan 430074China key laboratory of Material chemistry for Energy Conversion and Storage School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of chemistry and Chemical Engineering Hubei University of TechnologyWuhan 430068China key laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China State key lab of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Mechanical Engineering Hubei University of TechnologyWuhan 430068China Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430074China School of chemistry Xi'an Jiaotong UniversityXi'an 710049China

Oxygen vacancies enable modulating surface reconstruction of transition metal oxides containing metal-oxygen polyhedrons into metallic oxyhydroxide for oxygen evolution reaction(OER),while revealing reconstructing mechanism is stuck by the requirement to precisely control exact sites of these ***,oxygen vacancies are localized only within MoO_(4)tetrahedrons rather than CoO_(6)octahedrons in CoMoO_(4)catalyst,guaranteeing coherent reconstruction of CoO_(6)octahedrons into pure CoOOH with tunable activities for ***,distorted tetrahedron accelerates the dissolution of Mo atoms into alkaline electrolyte,triggering spontaneous transition of partial CoMoO_(4)into Co(OH)_(2).CoO_(6)octahedrons in both CoMoO_(4)and Co(OH)_(2)can transform pure CoOOH completely at lower potential,resulting in excess intrinsic activity whose summit is identified by overpotential at 10 mA cm^(-2)with 22.9%reduction and Tafel slope with 65.3%***-defined manipulation over the distorted polyhedrons offers one versatile knob to precisely modulate electronic structure of oxide catalysts with outstanding OER performance.

关键词： metal-oxygen polyhedron oxygen evolution reaction oxygen vacancy Raman spectroscopy

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Causal reasoning in typical computer vision tasks

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Science china(Technological Sciences) 2024年第1期67卷 105-120页

作者： ZHANG KeXuan SUN QiYu ZHAO ChaoQiang TANG Yang key laboratory of Advanced Control and Optimization for Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China National key laboratory of Air based Information Perception and Fusion Luoyang 471000China Luoyang Institute of Electro Optical Equipment of Avic Luoyang 471000China

Deep learning has revolutionized the field of artificial *** on the statistical correlations uncovered by deep learning-based methods,computer vision tasks,such as autonomous driving and robotics,are growing *** being the basis of deep learning,such correlation strongly depends on the distribution of the original data and is susceptible to uncontrolled *** the guidance of prior knowledge,statistical correlations alone cannot correctly reflect the essential causal relations and may even introduce spurious *** a result,researchers are now trying to enhance deep learningbased methods with causal *** theory can model the intrinsic causal structure unaffected by data bias and effectively avoids spurious *** paper aims to comprehensively review the existing causal methods in typical vision and visionlanguage tasks such as semantic segmentation,object detection,and image *** advantages of causality and the approaches for building causal paradigms will be *** roadmaps are also proposed,including facilitating the development of causal theory and its application in other complex scenarios and systems.

关键词： causal reasoning computer vision tasks vision-language tasks semantic segmentation object detection

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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang Zhang Qing-Lin Cheng Wei Sun Yi Zhao Zhi-Min Li key lab of ministry of education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina china Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex *** is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency *** this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western china is *** with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation *** comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are *** the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy *** entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their ***,the weak links in energy utilization are identified,and energy conservation and consumption reduction are *** above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

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Phase-stable wide-bandgap perovskites enabled by suppressed ion migration

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Journal of Energy chemistry 2024年第9期96卷 120-128页

作者： Zhiyu Gao Yu Zhu Jingwei Zhu Cong Chen Zongjin Yi Yi Luo Yuliang Xu Kai Wu Tianshu Ma Fangfang Cao Zijun Chen Fang Yao Juncheng Wang Wenwu Wang Chuanxiao Xiao Hao Huang Hongxiang Li Qianqian Lin Pei Cheng Changlei Wang Xia Hao Guanggen Zeng Dewei Zhao College of Materials Science and Engineering&Institute of New Energy and Low-Carbon Technology&Engineering Research Center of Alternative Energy Materials and Devices Ministry of EducationSichuan UniversityChengdu 610065SichuanChina School of Optoelectronic Science and Engineering&Collaborative Innovation Center of Suzhou Nano Science and Technology Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province&Key Lab of Modern Optical Technologies of Education Ministry of ChinaSoochow UniversitySuzhou 215006JiangsuChina Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201ZhejiangChina Ningbo New Materials Testing and Evaluation Center Co.Ltd Ningbo 315201ZhejiangChina State key laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structure&School of Resources Environment and MaterialsGuangxi UniversityNanning 530004GuangxiChina key lab of Artificial Micro-and Nano-Structures of ministry of education of china School of Physics and TechnologyWuhan UniversityWuhan 430072HubeiChina College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065SichuanChina

Wide-bandgap(>1.7 eV)perovskites suffer from severe light-induced phase segregation due to high bromine content,causing irreversible damage to devices ***,the strategies of suppressing photoinduced phase segregation and related mechanisms have not been fully ***,we report a new passivation agent 4-aminotetrahydrothiopyran hydrochloride(4-ATpHCl)with multifunctional groups for the interface treatment of a 1.77-eV wide-bandgap perovskite film.4-ATpH^(+)impeded halogen ion migration by anchoring on the perovskite surface,leading to the inhibition of phase segregation and thus the passivation of defects,which is ascribed to the interaction of 4-ATpH^(+)with perovskite and the formation of low-dimensional ***,the champion device achieved an efficiency of 19.32%with an open-circuit voltage(V_(OC))of 1.314 V and a fill factor of 83.32%.Moreover,4-ATpHCl modified device exhibited significant improved stability as compared with control *** target device maintained 80%of its initial efficiency after 519 h of maximum power output(MPP)tracking under 1 sun illumination,however,the control device showed a rapid decrease in efficiency after 267 ***,an efficiency of 27.38%of the champion 4-terminal all-perovskite tandem solar cell was achieved by mechanically stacking this wide-bandgap top subcell with a 1.25-eV low-bandgap perovskite bottom subcell.

关键词： Wide-bandgap perovskite Phase segregation lon migration Interface post-treatment All-perovskite tandems

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