检索结果-南通市图书馆

Chinese Geographical Science 2023年第3期33卷 503-511页

作者： YAN Guangxuan WANG Jieqi LUO Tingting CHEN Weiwei SHAO Yun LI Chunxi Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control(Ministry of Education) School of EnvironmentHenan Normal UniversityXinxiang 453007China College of Life Sciences Henan Normal UniversityXinxiang 453007China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China

Globally,agricultural soils are considered as one of the most important sources of greenhouse gas(GHG)emissions.No-tillage(NT),one of the most admired ways of climate-smart agriculture,has been deemed to have co-benefit to mitigation of GHG emissions and sustainability for crop yield,however,the effect of NT on GHG emissions is controversial.This study analyzed the overall effects of NT on GHG emissions,as well as the moderators that significantly influenced the overall effects,of the wheat-based rotation cropping systems in China through meta-analysis.The results showed that the overall effect size of NT on methane(CH4)uptake,nitrous oxide(N2O)emission,and global warming potential(GWP)was 0.70(95%Confidence Interval(CI):0.21–1.19),-0.27(95%CI:-0.72–0.18),and-0.39(95%CI:-1.01–0.23),respectively.In temperate climate zones with alkaline soils,the nitrogen application rate of 120–240 kg/ha,NT could significantly reduce GHG emissions and GWP.However,the mitigation effect will be weakened along with NT duration,except for proper straw addition.Overall,NT has the potential to reduce GHG emissions from wheat-based rotation systems in China,but it is necessary to implement NT depending on local conditions,soil characteristics,and field management.

关键词： Wheat soil rotation

Chemical characteristics and source apportionment of PM_(2.5) in a petrochemical city: Implications for primary and secondary carbonaceous component

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Journal of Environmental Sciences 2021年第5期33卷 322-335页

作者： guangxuan yan Puzhen Zhang Jie yang Jingwen Zhang Guifen Zhu Zhiguo Cao Jing Fan Zirui Liu Yuesi Wang School of Environment Henan Normal UniversityKey Laboratory for Yellow River and Huai River Water Environment and Pollution ControlMinistry of EducationHenan Key Laboratory for Environmental Pollution ControlXinxiang 453007China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of ScienceXiamen 361021China University of Chinese Academy of Science Beijing 100049China

To study the pollution features and underlying mechanism of PM_(2.5) in Luoyang, a typical developing urban site in the central plain of China, 303 PM_(2.5) samples were collected from April 16 to December 29, 2015 to analyze the elements, water soluble inorganic ions, organic carbon and elemental carbon. The annual mean concentration of PM_(2.5) was 142.3 μg/m^(3), and 75% of the daily PM_(2.5) concentrations exceeded the 75 μg/m^(3). The secondary inorganic ions, organic matter and mineral dust were the most abundant species, accounting for 39.6%, 19.2% and 9.3% of the total mass concentration, respectively. But the major chemical components showed clear seasonal dependence. SO_(4)^(2-) was most abundant specie in spring and summer, which related to intensive photochemical reaction under high O_3 concentration. In contrast, the secondary organic carbon and ammonium while primary organic carbon and ammonium significantly contributed to haze formation in autumn and winter, respectively. This indicated that the collaboration effect of secondary inorganic aerosols and carbonaceous matters result in heavy haze in autumn and winter. Six main sources were identified by positive matrix factorization model: industrial emission, combustion sources, traffic emission, mineral dust, oil combustion and secondary sulfate, with the annual contribution of 24%, 20%, 24%, 4%, 5% and 23%, respectively. The potential source contribution function analysis pointed that the contribution of the local and short-range regional transportation had significant impact. This result highlighted that local primary carbonaceous and precursor of secondary carbonaceous mitigation would be key to reduce PM_(2.5) and O_3 during heavy haze episodes in winter and autumn.

关键词： PM_(2.5) Seasonal variations Positive matrix factorization Emission sources

Emerging transporter-targeted nanoparticulate drug delivery systems

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Acta Pharmaceutica Sinica B 2019年第1期9卷 49-58页

作者： Hongyan Su yan Wang Shuo Liu Yue Wang Qian Liu guangxuan Liu Qin Chen Department of Pharmacy Cancer Hospital of China Medical University Liaoning Cancer Hospital & Institute

Transporter-targeted nanoparticulate drug delivery systems(nano-DDS) have emerged as promising nanoplatforms for efficient drug delivery. Recently, great progress in transporter-targeted strategies has been made, especially with the rapid developments in nanotherapeutics. In this review, we outline the recent advances in transporter-targeted nano-DDS. First, the emerging transporter-targeted nano-DDS developed to facilitate oral drug delivery are reviewed. These include improvements in the oral absorption of protein and peptide drugs, facilitating the intravenous-to-oral switch in cancer chemotherapy. Secondly, the recent advances in transporter-assisted brain-targeting nano-DDS are discussed,focusing on the specific transporter-based targeting strategies. Recent developments in transportermediated tumor-targeting drug delivery are also discussed. Finally, the possible transport mechanisms involved in transporter-mediated endocytosis are highlighted, with special attention to the latest findings of the interactions between membrane transporters and nano-DDS.

关键词： Transporter Nano-DDS Oral delivery Brain-targeting Tumor-targeting

Chemical characterization and source identification of PM_(2.5) in Luoyang after the clean air actions

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Journal of Environmental Sciences 2022年第5期34卷 265-276页

作者： Min Xu Zirui Liu Bo Hu guangxuan yan Jianan Zou Shuman Zhao Jingxiang Zhou Xianhui Liu Xueping Zheng Xiaoyan Zhang Jing Cao Mengshuang Guan Yirong Lv yanyun Zhang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control Henan Key Laboratory for Environmental Pollution ControlSchool of EnvironmentHenan Normal UniversityXinxiang 453007China Luoyang Eco-Environmental Monitoring Center of Henan Province Luoyang 471002China Luoyang Radiation Environment Service Office Luoyang 471002China 3 Clear Science&Technology Co. LtdBeijing 100029China

Luoyang is a typical heavy industrial city in China,with a coal-dominated energy structure and serious air pollution.Following the implementation of the clean air actions,the physic-ochemical characteristics and sources of PM_(2.5) have changed.A comprehensive study of PM_(2.5) was conducted from October 16,2019 to January 23,2020 to evaluate the effectiveness of previous control measures and further to provide theory basis for more effective policies in the future.Results showed that the aerosol pollution in Luoyang in autumn and win-ter is still serious with the average concentration of 91.1 μg/m^(3),although a large reduction(46.9%)since 2014.With the contribution of nitrate increased from 12.5%to 25.1%and sul-fate decreased from 16.7%to 11.2%,aerosol pollution has changed from sulfate-dominate to nitrate-dominate.High NO_(3)^(-)/SO_(4)^(2-)ratio and the increasing of NO_(3)^(-)/SO_(4)^(2-)ratio with the aggravation of pollution indicating vehicle exhaust playing an increasingly important role in PM_(2.5) pollution in Luoyang,especially in the haze processes.Secondary inorganic ions contributed significantly to the enhancement of PM_(2.5) during the pollution period.The high value of Cl^(-)/Na^(+)and EC concentration indicate coal combustion in Luoyang is still serious.The top three contributor sources were secondary inorganic aerosols(33.3%),coal combus-tion(13.6%),and industrial emissions(13.4%).Close-range transport from the western and northeastern directions were more important factors in air pollution in Luoyang during the sampling period.It is necessary to strengthen the control of coal combustion and reduce vehicle emissions in future policies.

关键词： Luoyang PM_(2.5) Chemical composition Source apportionment

Characteristics of PM_(2.5) pollution in Beijing after the improvement of air quality

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Journal of Environmental Sciences 2021年第2期33卷 1-10页

作者： Xiaojuan Huang Guiqian Tang Junke Zhang Baoxian Liu Chao Liu Jin Zhang Leilei Cong Mengtian Cheng guangxuan yan Wenkang Gao Yinghong Wang Yuesi Wang Plateau Atmosphere and Environment Key Laboratory of Sichuan Province School of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Faculty of Geosciences and Environmental Engineering Southiuest Jiaotong UniversityChengdu 611756China Beijing Municipal Environmental Monitoring Centre Beijing 100048China Fengtai District Ecology and Environment Bureau Beijing 100071China School of Environment Henan Normal UniuersityKey Laboratory Jor YellouRiuer and Huai Riuer Water Environment and Pollution ControlMinistry of EducationHenan Key Laboratory/or EnvironmentaI Pollution ControlXinxiang 453007China

Following the implementation of the strictest clean air policies to date in Beijing,the physicochemical characteristics and sources of PM_(2.5) have changed over the past few years.To improve pollution reduction policies and subsequent air quality further,it is necessary to explore the changes in PM_(2.5) over time.In this study,over one year(2017-2018)field study based on filter sampling(TH-150C;Wuhan Tianhong,China)was conducted in Fengtai District,Beijing,revealed that the annual average PM_(2.5) concentration(64.8±43.1μg/m^3)was significantly lower than in previous years and the highest PM_(2.5) concentration occurred in spring(84.4±59.9μg/m^3).Secondary nitrate was the largest source and accounted for 25.7%of the measured PM_(2.5).Vehicular emission,the second largest source(17.6%),deserves more attention when considering the increase in the number of motor vehicles and its contribution to gaseous pollutants.In addition,the contribution from coal combustion to PM_(2.5) decreased significantly.During weekends,the contribution from EC and NO3−increased whereas the contributions from SO4^2−,OM,and trace elements decreased,compared with weekdays.During the period of residential heating,PM_(2.5) mass decreased by 23.1%,compared with non-heating period,while the contributions from coal combustion and vehicular emission,and related species increased.With the aggravation of pollution,the contribution of vehicular emission and secondary sulfate increased and then decreased,while the contribution of NO3−and secondary nitrate continued to increase,and accounted for 34.0%and 57.5%of the PM_(2.5) during the heavily polluted days,respectively.

关键词： PM_(2.5) Seasonal variations Chemical composition Source apportionment Pollution evolution

抗日战争时期中共中央华中局加强党的建设述论

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军事历史研究 2021年第5期35卷 1-10页

作者：余广选闫耀升国防大学军事管理学院北京100091

1941年5月20日,中共中央华中局正式成立。以刘少奇为书记的华中局认识到,实现中共中央巩固华北、发展华中的战略目标,担负起华中局的使命任务,必须正确贯彻落实中共中央的路线、方针、政策,发挥好党的各级组织对根据地党政军民的集中统... 详细信息

1941年5月20日,中共中央华中局正式成立。以刘少奇为书记的华中局认识到,实现中共中央巩固华北、发展华中的战略目标,担负起华中局的使命任务,必须正确贯彻落实中共中央的路线、方针、政策,发挥好党的各级组织对根据地党政军民的集中统一领导作用。华中局从三个方面加强了根据地党的领导和党的建设,一是通过加强党性历练、开展党内斗争和强化党内教育,提高了广大党员干部的思想觉悟和政治觉悟;二是通过大力加强军队党、地方党的组织建设,并有效规范二者之间的关系,引导华中地区各领域各方向党的各级组织更加科学有序地发挥作用;三是通过开展整风运动、加强锄奸工作、严格群众纪律,凝聚了各方力量,纯洁了党的组织,党政军民形成了空前团结的局面。一整套加强党的建设的“组合拳”,有效强化了党对华中地区的领导,使党在华中地区的工作局面迅速打开,对推动华中地区融入抗战大局、服务抗战大局发挥了极其重要的作用。

关键词：华中局党的建设新四军 “皖南事变”

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新乡市细颗粒物和臭氧协同污染特征

环境污染与防治 2023年第4期45卷 541-543,548页

作者：赵阳李崇浩周凯闫广轩河南省新乡生态环境监测中心河南新乡453003 河南师范大学环境学院黄淮水环境与污染防控教育部重点实验室河南新乡453007 河南科技学院园艺园林学院河南新乡453003

细颗粒物(PM_(2.5))和臭氧(O_(3))协同控制已是近年的研究热点。基于2020年新乡市环境空气质量自动监测数据和气象数据等,研究了新乡市PM_(2.5)和O_(3)的协同污染特征,以期为新乡市的大气协同污染治理提供科学参考。结果表明,PM_(2.5)... 详细信息

细颗粒物(PM_(2.5))和臭氧(O_(3))协同控制已是近年的研究热点。基于2020年新乡市环境空气质量自动监测数据和气象数据等,研究了新乡市PM_(2.5)和O_(3)的协同污染特征,以期为新乡市的大气协同污染治理提供科学参考。结果表明,PM_(2.5)污染和O_(3)污染分别主要集中在秋冬季和春夏季。定义O_(3)质量浓度超过80μg/m^(3)、PM_(2.5)质量浓度超过75μg/m^(3)为复合污染,全年共出现133次复合污染。新乡市的复合污染多出现在温度为5~25℃、相对湿度低于80%、风向为北风、风速低于1.5 m/s的条件下,PM_(2.5)主导型污染时有机碳大都超过10μg/m^(3),NO 2大都超过30μg/m^(3);O_(3)主导型污染时有机碳大都小于10μg/m^(3),NO 2大都小于30μg/m^(3)。PM_(2.5)与O_(3)之间可能存在对共同前体物的竞争反应。

关键词：季节特征细颗粒物臭氧二次反应

任务叠加与机制叠加:中国式现代化生成路径的尝试性阐释

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社会主义研究 2023年第6期 1-9页

作者：马光选云南大学马克思主义学院

时空压缩条件下,作为后发现代化国家的中国需要在几十年内完成发达国家几百年的现代化任务,出现了多行业、多领域、多阶段、多时空、多区域的“叠加共进”现象。这种“任务叠加”的现代化模式是传统机制与现代机制历时性接续“叠加”的... 详细信息

时空压缩条件下,作为后发现代化国家的中国需要在几十年内完成发达国家几百年的现代化任务,出现了多行业、多领域、多阶段、多时空、多区域的“叠加共进”现象。这种“任务叠加”的现代化模式是传统机制与现代机制历时性接续“叠加”的结果。中国传统国家治理机制的重新激活、再利用和现代转化,形成更新迭代之后的新自主性机制、新非均衡性机制、新整合动员机制、新代际分步协同机制和新稳定性机制等具有功能叠加属性的现代化机制。传统机制与现代机制在中国式现代化进程中的相互套嵌、勾连融合,以中国巨型国家丰富治理经验的现代性转化、中国化时代化马克思主义的强大理论指导能力、中国共产党的强大政治引领能力和社会主义中国强大的国家建设能力为独有的前提条件。这充分证明,坚持和加强中国共产党的领导是中国式现代化的根本性质和巨大优势。

关键词：中国式现代化后发型现代化社会主义现代化

Research on Multi-Authority CP-ABE Access Control Model in Multicloud

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China Communications 2020年第8期17卷 220-233页

作者： Shengli Zhou guangxuan Chen Guangjie Huang Jin Shi Ting Kong Department of Computer and Information Security Zhejiang Police CollegeHangzhou 310053China Institute of Big-data and Network Security Zhejiang Police CollegeHangzhou 310053China Institute of Software Chinese Academy of SciencesBeijing 100190China

In order to solve the problems of data sharing security and policy conflict in multicloud storage systems(MCSS), this work designs an attribute mapping mechanism that extends ciphertext policy attribute-based encryption(CP-ABE), and proposes a multi-authority CP-ABE access control model that satisfies the need for multicloud storage access control. The mapping mechanism mainly involves the tree structure of CP-ABE and provides support for the types of attribute values. The framework and workflow of the model are described in detail. The effectiveness of the model is verified by building a simple prototype system, and the performance of the prototype system is analyzed. The results suggest that the proposed model is of theoretical and practical significance for access control research in MCSS. The CP-ABE has better performance in terms of computation time overhead than other models.

关键词： CP-ABE access control multicloud multi-authority trust

Reclamation-oriented spatiotemporal evolution of coastal wetland along Bohai Rim,China

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Acta Oceanologica Sinica 2022年第9期41卷 192-204页

作者： Fan Wei Mei Han guangxuan Han Min Wang Lixin Tian Jiqian Zhu Xianglun Kong College of Geography and Environment Shandong Normal UniversityJinan250358China Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai264003China

Coastal wetlands are located in the ecotone of interaction between the land surface and sea,and anthropogenic activities extensively interfere with these wetlands through the reclamation of large tidal wetlands and destruction of the function of the ecosystems.In this study,we investigated the dynamic evolutionary characteristics of the Bohai Rim coastal area over the past 40 years using the Modified Normalized Difference Water Index,the fractal dimension,object-oriented classification,the land-use transfer trajectory,and regression analysis.Additionally,we quantified and monitored the evolution of reclamation and analyzed the correlation between reclamation and coastal wetlands based on 99 Landsat-2,-5,and-8 images(at 60 m and 30 m spatial resolution) over the period 1980–2019.The results are as follows.(1) The coastline of the Bohai Rim increased by 1 631.2 km from 1980 to2019 with a zigzag variation.The artificial coastline increased by 2 946.1 km,whereas the natural coastline decreased by 90%.(2) The area of man-made wetlands increased by 3 736.9 km~2,the area of construction land increased by 1 008.4 km~2,and the natural wetland area decreased by 66%.The decrease of tidal flats is the main contributor to the decrease of natural wetland area(takes account for 91.1%).Coastal areas are affected by intense human disturbance,which was taken place across a large area of tidal flats and caused the landscape to fragment and be more heterogeneous.The coastal zone development activities were primarily concentrated in the southern Laizhou Bay,the Yellow River Delta,the Bohai Bay,the northern Liaodong Bay,and the Pulandian Bay.The solidified shorelines and increase in sea level have resulted in intertidal wetlands decreasing and impaired wetland ecology.(3) There is a good agreement between reclamation and the size of the coastal wetlands.Both land reclamation and the reduction in coastal wetland areas are significantly related to the population size,fishery output value,and urbanization rate.In summary,human activities

关键词： Bohai Rim coastal wetlands land reclamation evolutionary mechanisms coastal management