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Regional Characteristics and Causes of Haze Events in Northeast China

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Chinese Geographical Science 2018年第5期28卷 836-850页

作者： CheN Weiwei ZHANG Shichun TONG Quansong ZHANG Xuelei ZHAO Hongmei MA Siqi XIU Aijun he yuexin Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of Sciences

Northeast China experiences severe atmospheric pollution, with an increasing occurrence of heavy haze episodes. However, the underlying forces driving haze formation during different seasons are poorly understood. In this study, we explored the spatio-temporal characteristics and causes of haze events in Northeast China by combining a range of data sources(i.e., ground monitoring, satellite-based products, and meteorological products). It was found that the ‘Shenyang-Changchun-Harbin(SCH)'city belt was the most polluted area in the region on an annual scale. The spatial distribution of air quality index(AQI) values had a clear seasonality, with the worst pollution occurring in winter, an approximately oval-shaped polluted area around western Jilin Province in spring, and the best air quality occurring in summer and most of the autumn. The three periods that typically experienced intense haze events were Period I from mid-October to mid-November(i.e., late autumn and early winter), Period II from late-December to February(i.e., the coldest time in winter), and Period III from April to mid-May(i.e., spring). During Period I, strong PM_(2.5) emissions from seasonal crop residue burning and coal burning for winter heating were the dominant reasons for the occurrence of extreme haze events(AQI > 300). Period II had frequent heavy haze events(200 he coldest months of January and February, which were due to high PM_(2.5) emissions from coal burning and vehicle fuel consumption, a lower atmospheric boundary layer, and stagnant atmospheric conditions. Haze events in Period III, with high PM_(10) concentrations, were primarily caused by the regional transportation of windblown dust from degraded grassland in central Inner Mongolia and bare soil in western Jilin Province. Local agricultural tilling could also release PM_(10) and enhance the levels of windblown dust from tilled soil. Better control of coal burning, fuel consumption, and crop residue burning in winter and autumn is urgently needed to address

关键词：特征和地区性事件中国东北原因 PM2.5 空气质量

Gibberellin promotes cambium reestablishment during secondary vascular tissue regeneration after girdling in an auxin-dependent manner in Populus

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Journal of Integrative Plant Biology 2024年第1期66卷 86-102页

作者： Yufei Zhang Lingyan Wang yuexin Wu Donghui Wang Xin‐Qiang he State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China

Secondary vascular tissue(SVT)development and regeneration are regulated by phytohormones.In this study,we used an in vitro SVT regeneration system to demonstrate that gibberellin(GA)treatment significantly promotes auxin-induced cambium reestablishment.Altering GA content by overexpressing or knocking down ent-kaurene synthase(KS)affected secondary growth and SVT regeneration in poplar.The poplar DELLA gene GIBBERELLIC ACID INSENSITIVE(PtoGAI)is expressed in a specific pattern during secondary growth and cambium regeneration after girdling.Overexpression of PtoGAI disrupted poplar growth and inhibited cambium regeneration,and the inhibition of cambium regeneration could be partially restored by GA application.Further analysis of the PtaDR5:GUS transgenic plants,the localization of PIN-FORMED 1(PIN1)and the expression of auxin-related genes found that an additional GA treatment could enhance the auxin response as well as the expression of PIN1,which mediates auxin transport during SVT regeneration.Taken together,these findings suggest that GA promotes cambium regeneration by stimulating auxin signal transduction.

关键词： auxin cambium gibberellin Populus secondary vascular tissue regeneration

From risk control to resilience: developments and trends of urban roads designed as surface flood passages to cope with extreme storms

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 103-120页

作者： Zhiyu Shao yuexin Li Huafeng Gong Hongxiang Chai College of Environment and Ecology Chongqing UniversityChongqing 400030China Key Laboratory of Ecological Environment of Ministry of Education of Three Gorges Reservoir Area Chongqing UniversityChongqing 400030China T.Y.Lin International Engineering Consulting(China)Co.Ltd. Chongqing 400045China

Urban roads can be designated as surface flood passages to transport excess runoff during extreme storms, thereby preventing local flooding, which is known as the major drainage system. However, this practice poses significant risks, including human loss and property damage, due to the high flow rate and velocity carried by roads. Moreover, urban roads with low flood-resilience may significantly hamper the transportation function during severe storms, leading to dysfunction of the city. Therefore, there is an urgent need to transform risk-oriented flood passages into resilient urban road-based flood passages. This paper presents a systematic review of existing methodologies in designing a road network-based flood passage system, along with the discussion of new technologies to enhance system resilience. The study also addresses current knowledge gaps and future directions. The results indicate that flood management measures based on the urban road network should integrate accessibility assessment, lifeline and emergency planning to ensure human well-being outcomes. Furthermore, the special needs and features of vulnerable groups must be taken into serious consideration during the planning stage. In addition, a data-driven approach is recommended to facilitate real-time management and evaluate future works.

关键词： Major drainage Flood mitigation Resilient city Stormwater model Urban flooding

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唐代丧葬花费考

华夏考古 2022年第1期 97-104页

作者：何月馨中国妇女儿童博物馆北京市100005

本文通过对相关文献材料的梳理,勾勒出唐代丧葬花费的基本面貌,如购买葬具和墓地、修建墓葬、准备墓志和随葬品等。就丧葬总花费而言,普通官员与厚葬的庶民之间差距并不大,反映了唐代城市和商品经济的发展、阶层流动性的加大;但与最高... 详细信息

本文通过对相关文献材料的梳理,勾勒出唐代丧葬花费的基本面貌,如购买葬具和墓地、修建墓葬、准备墓志和随葬品等。就丧葬总花费而言,普通官员与厚葬的庶民之间差距并不大,反映了唐代城市和商品经济的发展、阶层流动性的加大;但与最高等级如皇室人群等仍然存在鸿沟,等级始终是影响葬事花费的重要因素。

关键词：唐代丧葬花费等级

Recent process developments in beneficiation and metallurgy of rare earths:A review

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Journal of Rare Earths 2024年第4期42卷 629-642页

作者： Shaokai Cheng Wenbo Li yuexin Han Yongsheng Sun Peng Gao Xiaolong Zhang School of Resources and Civil Engineering Northeastern UniversityShenyang110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang110819China

Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly prominent.With the continuous depletion of rare earth(RE)resources,developing high-efficiency beneficiation and eco-friendly metallurgical processes has attracted widespread attention.This paper reviews the major minerals exploited for RE production and their deposits,as well as the beneficiation and metallurgical processes of RE minerals.Bastnaesite,monazite,mixed RE ores,and ion-adsorption clays are the main raw materials in the world to date.RE-bearing ores(except ion-adsorption minerals)are generally beneficiated by flotation,gravity and magnetic separation techniques.The mainstream metallurgical processes for bastnaesite,monazite and mixed RE concentrates are oxidation roasting-HCl leaching,caustic soda decomposition and high-temperature concentrated sulfuric acid roasting,respectively.Ion-adsorption clays are directly processed by in situ leaching-precipitation/solvent extraction.To achieve the sustainable development of RE resources,it is essential to further explore innovative techniques to achievecomprehensive utilization and cleaner production.

关键词： Rare earths Beneficiation processes Metallurgical processes Cleaner production

A Simple and Effective Surface Defect Detection Method of Power Line Insulators for Difficult Small Objects

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Computers, Materials & Continua 2024年第4期79卷 373-390页

作者： Xiao Lu Chengling Jiang Zhoujun Ma Haitao Li yuexin Liu State Grid Jiangsu Electric Power Co. Ltd.Nanjing210024China State Grid Changzhou Power Supply Company Changzhou213003China

Insulator defect detection plays a vital role in maintaining the secure operation of power systems.To address the issues of the difficulty of detecting small objects and missing objects due to the small scale,variable scale,and fuzzy edge morphology of insulator defects,we construct an insulator dataset with 1600 samples containing flashovers and breakages.Then a simple and effective surface defect detection method of power line insulators for difficult small objects is proposed.Firstly,a high-resolution featuremap is introduced and a small object prediction layer is added so that the model can detect tiny objects.Secondly,a simplified adaptive spatial feature fusion(SASFF)module is introduced to perform cross-scale spatial fusion to improve adaptability to variable multi-scale features.Finally,we propose an enhanced deformable attention mechanism(EDAM)module.By integrating a gating activation function,the model is further inspired to learn a small number of critical sampling points near reference points.And the module can improve the perception of object morphology.The experimental results indicate that concerning the dataset of flashover and breakage defects,this method improves the performance of YOLOv5,YOLOv7,and YOLOv8.In practical application,it can simply and effectively improve the precision of power line insulator defect detection and reduce missing detection for difficult small objects.

关键词： Insulator defect detection small object power line deformable attention mechanism

MIL-100(V) derived porous vanadium oxide/carbon microspheres with oxygen defects and intercalated water molecules as high-performance cathode for aqueous zinc ion battery

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Journal of Energy Chemistry 2024年第3期90卷 578-589,I0013页

作者： yuexin Liu Jian Huang Xiaoyu Li Jiajia Li Jinhu Yang Kefeng Cai Shanghai Key Laboratory of Development and Application for Metal-Functional Materials Key Laboratory of Advanced Civil Engineering MaterialsMinistry of EducationSchool of Materials Science&EngineeringTongji UniversityShanghai 201804China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201800China Research Center for Translational Medicine East HospitalTongji University School of MedicineShanghai 200092China

The development of aqueous zinc ion battery cathode materials with high capacity and high magnification is still a challenge.herein,porous vanadium oxide/carbon(p-VO_(x)@C,mainly VO_(2) with a small amount of V_(2)O_(3)) core/shell microspheres with oxygen vacancies are facilely fabricated by using a vanadium-based metal-organic framework(MIL-100(V)) as a sacrificial template.This unique structure can improve the conductivity of the VO_(x),accelerate electrolyte diffusion,and suppress structural collapse during circulation.Subsequently,H_(2)O molecules are introduced into the interlayer of VO_(x) through a highly efficient in-situ electrochemical activation process,facilitating the intercalation and diffusion of zinc ions.After the activation,an optimal sample exhibits a high specific capacity of 464.3 mA h g^(-1) at0.2 A g^(-1) and 395.2 mA h g^(-1) at 10 A g^(-1),indicating excellent rate performance.Moreover,the optimal sample maintains a capacity retention of about 89.3% after 2500 cycles at 10 A g^(-1).Density functional theory calculation demonstrates that the presence of oxygen vacancies and intercalated water molecules can significantly reduce the diffusion barrier for zinc ions.In addition,it is proved that the storage of zinc ions in the cathode is achieved by reversible intercalation/extraction during the charge and discharge process through various ex-situ analysis technologies.This work demonstrates that the p-VO_(x)@C has great potential for applications in aqueous ZIBs after electrochemical activation.

关键词： Metal-organic frameworks Vanadium oxide Carbon Zn-ion batteries Electrochemical activation

Changes in air pollutants during the COVID-19 lockdown in Beijing:Insights from a machine-learning technique and implications for future control policy

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Atmospheric and Oceanic Science Letters 2021年第4期14卷 63-69页

作者： Jiabao Hu Yuepeng Pan yuexin he Xiyuan Chi Qianqian Zhang Tao Song Weishou Shen Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlSchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjingChina State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina National Meteorological Center China Meteorological AdministrationBeijingChina National Satellite Meteorological Center China Meteorological AdministrationBeijingChina

基于2015–2020年北京35个环境空气站和20个气象站观测资料,应用机器学习方法(随机森林算法)分离了气象条件和源排放对大气污染物浓度的影响.结果发现,为应对疫情采取的隔离措施使北京2020年春节期间大气污染物浓度降低了35.1%–51.8%;... 详细信息

基于2015–2020年北京35个环境空气站和20个气象站观测资料,应用机器学习方法(随机森林算法)分离了气象条件和源排放对大气污染物浓度的影响.结果发现,为应对疫情采取的隔离措施使北京2020年春节期间大气污染物浓度降低了35.1%–51.8%;其中,背景站氮氧化物和一氧化碳浓度的降幅最大,超过了以往报道较多的交通站点.同时,2020年春节期间的气象条件不利于污染物扩散,导致多次霾污染事件发生.为进一步改善北京空气质量,未来需要优化减排策略.

关键词：机器学习大气污染去气象化 COVID-19 减排策略

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情理之间——再论唐代招魂葬

四川文物 2023年第3期 72-82页

作者：何月馨蔡经纬中国妇女儿童博物馆成都金沙遗址博物馆

通过辨析唐墓中明确采用招魂葬的墓葬实例,结合相关文献,可观察唐代招魂葬的基本面貌。研究表明,唐代招魂葬不埋葬尸骨,但有“替代形体”在场,招魂葬广泛流行于不同阶层中,且成为部分人群的主动选择。中古时期招魂葬由俗入礼的过程,反... 详细信息

通过辨析唐墓中明确采用招魂葬的墓葬实例,结合相关文献,可观察唐代招魂葬的基本面貌。研究表明,唐代招魂葬不埋葬尸骨,但有“替代形体”在场,招魂葬广泛流行于不同阶层中,且成为部分人群的主动选择。中古时期招魂葬由俗入礼的过程,反映了晋唐之间生死观念的变迁,传统“形神异制,墓庙大分”的观念淡化,墓葬藏形与藏神并存。此外,招魂葬的流行也反映了时人在情理之间所寻求到的平衡,在“以孝治国”的大背景下,制定和调整礼制的过程中,人情成为重要的影响因素。

关键词：唐墓招魂葬丧葬习俗生死观