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Sources and characteristics of fine particles over the Yellow Sea and Bohai Sea using online single particle aerosol mass spectrometer

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Journal of Environmental Sciences 2015年第3期27卷 62-70页

作者： Huaiyu Fu Mei Zheng Caiqing Yan Xiaoying Li Huiwang Gao Xiaohong Yao Zhigang Guo yuanhang zhang Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and Engineering Fudan University State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China

Marine aerosols over the East China Seas are heavily polluted by continental sources. During the Chinese Comprehensive Ocean Experiment in November 2012, size and mass spectra of individual atmospheric particles in the size range from 0.2 to 2.0 μm were measured on board by a single particle aerosol mass spectrometer （SPAMS）. The average hourly particle number （PN） was around 4560 ＋ 3240 in the South Yellow Sea （SYS）, 2900 ± 3970 in the North Yellow Sea （NYS）, and 1700 ± 2220 in the Bohai Sea （BS）. PN in NYS and BS varied greatly over 3 orders of magnitude, while that in SYS varied shghtly. The size distributions were fitted with two log-normal modes. Accumulation mode dominated in NYS and BS, especially during episodic periods. Coarse mode particles played an important role in SYS. Particles were dassifled using an adaptive resonance theory based neural network algorithm （ART-2a）. Six particle types were identified with secondary-containing, aged sea-salt, soot-like, biomass burning, fresh sea-salt, and lead-containing particles accounting for 32%, 21%, 18%, 16%, 4%, and 3% of total PN, respectively. Aerosols in BS were relatively enriched in particles from anthropogenic sources compared to SYS, probably due to emissions from more developed upwind regions and indicating stronger influence of continental outflow on marine environment. Variation of source types depended mainly on origins of transported air masses. This study examined rapid changes in PN, size distribution and source types of fine particles in marine atmospheres. It also demonstrated the effectiveness of hi,h-time-resolution source apportionment by ART-2a.

关键词： Source apportionment Marine aerosol Size and chemical composition SPAMS East China Sea

Fluxes of NH_3 and HNO_3 over heathland in the Netherlands:implications for chemical interactions

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Journal of Environmental Sciences 1997年第1期9卷 49-58页

作者： zhang yuanhang Center of Environmental Sciences,Peking University,Beijing 100871,China Center of Environmental Sciences Peking University Beijing 100871 China

The surface exchange of NH_3 and HNO_3 gases over heathland was measured with the aerodynamic gradient method in Leende,the Netherlands during April 25 and May 9,*** to reactions in the system NH_3,HNO_3 and NH_4NO_3,the NH_3 deposition flux is overestimated,while HNO_3 shows apparent emission fluxes mostly during the field *** reveal that NH_3 gradients are influenced slightly by HNO_3 and the HNO_3 gradients are strongly controlled by the NH_3.A clear relationship between NH_3 and HNO_3 gradient is suggested by the Leende experiment. Before the late afternoon,NH_3 deposition gradients will cause HNO_3 upward gradients,meanwhile the NH_3 gradients themselves will become *** the HNO_3 upward gradient reaches maxi- mum,the NH_3 deposition gradients will be enlarged or the emission gradients depressed,while the HNO_3 upward gradients become smaller.

关键词： dry deposition ammonia nitric acid equilibrium,fluxes.

Interactions between water vapor and atmospheric aerosols have key roles in air quality and climate change

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National Science Review 2018年第4期5卷 452-454页

作者： Zhijun Wu Jie Chen Yu Wang Yishu Zhu Yuechen Liu Bai Yao yuanhang zhang Min Hu State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University Centre for Atmospheric Sciences School of Earth and Environmental Sciences University of Manchester Beijing Innovation Center for Engineering Sciences and Advanced Technology Peking University

INTRODUCTION Atmospheric aerosols,which are ubiquitous in the planetary boundary layer,have received much attention due to their effects on visibility,climate and human ***,a semi-volatile species,is ubiquitous in the atmosphere as *** interaction between water vapor and aerosols plays a key role in determining the aerosol properties in the atmosphere and therefore has great effects on both air quality(Fig.1a and b)and climate

关键词： SECONDARY ORGANIC AEROSOLS ICE NUCLEATION PHASE STATE PARTICLES

Impacts of synoptic circulation on surface ozone pollution in a coastal eco-city in Southeastern China during 2014-2019

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Journal of Environmental Sciences 2023年第5期127卷 143-157页

作者： Yu Yan Xuesong Wang Zhengchao Huang Kun Qu Wenbin Shi Zimu Peng Limin Zeng Shaodong Xie yuanhang zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China International Joint Laboratory for Regional Pollution Control Ministry of EducationBeijing 100816China Center for Environmental Education and Communications of Ministry of Ecology and Environment Beijing 100020China Beijing Innovation Center for Engineering Science and Advanced Technology Peking UniversityBeijing 100871China CAS Center for Excellence in Regional Atmospheric Environment Chinese Academy of SciencesXiamen 361021China

The coastal eco-city of Fuzhou in Southeastern China has experienced severe ozone(O_(3))episodes at times in recent *** this study,three typical synoptic circulations types(CTs)that influenced more than 80%of O_(3) polluted days in Fuzhou during 2014-2019 were identified using a subjective *** characteristics of meteorological conditions linked to photochemical formation and transport of O_(3) under the three CTs were *** Air Quality Model with extensions was applied to simulate O_(3) episodes and to quantify O_(3) sources from different regions in *** Fuzhou was located to the west of a high-pressure system(classified as“East-ridge”),more warm southwesterly currents flowed to Fuzhou,and the effects of cross-regional transport from Guangdong province and high local production promoted the occurrence of O_(3) *** a uniform pressure field with a low-pressure system occurring to the east of Fuzhou(defined as“East-low”),stagnant weather conditions caused the strongest local production of O_(3) in the atmospheric boundary *** by high-pressure systems over the mainland(categorized as“Inland-high”),northerly airflows enhanced the contribution of cross-regional transport to O_(3) in *** abnormal increases of the“East-ridge”and“Inland-high”were closely related to O_(3) pollution in Fuzhou in April and May 2018,resulting in the annual maximum number of O_(3) polluted days during recent ***,the rising number of autumn O_(3) episodes in 2017-2019 was mainly related to the“Inland-high”,indicating the aggravation of cross-regional transport and highlighting the necessity of enhanced regional collaboration and efforts in combating O_(3) pollution.

关键词： Ozone pollution Synoptic circulation Regional transport Chemical production

Characteristics and formation mechanism of regional haze episodes in the Pearl River Delta of China

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Journal of Environmental Sciences 2018年第1期30卷 236-249页

作者： Wenguang Li Xingang Liu yuanhang zhang Kang Sun Yusheng Wu Rui Xue Limin Zeng Yu Qu Junling An State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 10087SChina State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChineseAcademy of SciencesBeijing 100029China

To investigate the characteristics and the specific mechanism of continuous haze,comprehensive measurements were conducted from 15 October to 19 November in the Atmospheric Environment Monitoring Super-Station in Heshan of Guangdong *** haze episodes occurred in October and November 2014 in the Pearl River Delta（PRD）region. The meteorological parameters, gas data, chemical compositions, and optical parameters of the aerosols were obtained. Among these events, the second haze episode,with the highest concentration of PM2.5 of 187.51 μg/m^3, was the most severe. NO^3-was always higher than SO_4^（2-）, which indicated that motor vehicles played an important role in the haze, even though the oxidation rate from SO_2 to SO_4^（2-）was faster than that of NOXto NO_3^-. The difference between the hourly averages of Na＋and K＋during the haze episode and clean days was small, implying that straw combustion and sea salt had no significant effect on the occurrence of haze, and the backward trajectories of the air masses also conformed with this result. The air pollutants were difficult to disperse because of the significant decrease in the planetary boundary layer（PBL） height. Relative humidity played a crucial role in the formation of haze by leading to hygroscopic growth of the diameter of aerosols.

关键词： Haze episodes Chemical characteristics Formation mechanism PRD

Fast increasing of surface ozone concentrations in Pearl River Delta characterized by a regional air quality monitoring network during 2006–2011

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Journal of Environmental Sciences 2014年第1期26卷 23-36页

作者： Jinfeng Li Keding Lu Wei Lv Jun Li Liuju Zhong Yubo Ou Duohong Chen Xin Huang yuanhang zhang College of Environmental Sciences Engineering Peking University Guangdong Provincial Environmental Monitoring Center

Based on the observation by a Regional Air Quality Monitoring Network including 16 monitoring stations, temporal and spatial variations of ozone （O3）, NO2 and total oxidant （Ox） were analyzed by both linear regression and cluster analysis. A fast increase of regional O3 concentrations of 0.86 ppbWyr was found for the annual averaged values from 2006 to 2011 in Guangdong, China. Such fast O3 increase is accompanied by a correspondingly fast NOx reduction as indicated by a fast NO2 reduction rate of 0,61 ppbV/yr. Based on a cluster analysis, the monitoring stations were classified into two major categories - rural stations （non-urban） and suburban/urban stations. The 03 concentrations at rural stations were relatively conserved while those at suburban/urban stations showed a fast increase rate of 2.0 ppbV/yr accompanied by a NO2 reduction rate of 1.2 ppbV/yr. Moreover, a rapid increase of the averaged O3 concentrations in springtime （13%/yr referred to 2006 level） was observed, which may result from the increase of solar duration, reduction of precipitation in Guangdong and transport from Eastern Central China. Application of smog production algorithm showed that the photochemical O3 production is mainly volatile organic compounds （VOC）-controlled. However, the photochemical O3 production is sensitive to both NOx and VOC for O3 pollution episode. Accordingly, it is expected that a combined NOx and VOC reduction will be helpful for the reduction of the O3 pollution episodes in Pearl River Delta while stringent VOC emission control is in general required for the regional O3 pollution control.

关键词： O3 cluster analysis temporal variation smog production algorithm Pearl River Delta

In situ monitoring of atmospheric nitrous acid based on multi-pumping flow system and liquid waveguide capillary cell

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Journal of Environmental Sciences 2016年第5期28卷 273-284页

作者： Yuhan Liu Keding Lu Huabin Dong Xin Li Peng Cheng Qi Zou Yusheng Wu Xingang Liu yuanhang zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University Institute of Energy and Climate Research: Troposphere (IEK-8) Forschungszentrum Juelich GmbH State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University

In the last four decades, various techniques including spectroscopic, wet chemical and mass spectrometric methods, have been developed and applied for the detection of ambient nitrous acid（HONO）. We developed a HONO detection system based on long path photometry which consists of three independent modules i.e., sampling module, fluid propulsion module and detection module. In the propulsion module, solenoid pumps are applied. With solenoid pumps the pulsed flow can be computer controlled both in terms of pump stroke volume and pulse frequency, which enables the attainment of a very stable flow rate. In the detection module, a customized Liquid Waveguide Capillary Cell（LWCC） is used. The customized LWCC pre-sets the optical fiber in-coupling with the liquid wave guide, providing the option of fast startup and easy maintenance of the absorption photometry. In summer 2014, our system was deployed in a comprehensive campaign at a rural site in the North China Plain. More than one month of high quality HONO data spanning from the limit of detection to 5 ppb were collected. Intercomparison of our system with another established system from Forschungszentrum Juelich is presented and discussed. In conclusion, our instrument achieved a detection limit of 10 ppt V within2 min and a measurement uncertainty of 7%, which is well suited for investigation of the HONO budget from urban to rural conditions in China.

关键词： HONO Photometry Field campaign Atmospheric chemistry

Insights into the phenomenon of an explosive growth and sharp decline in haze:A case study in Beijing

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Journal of Environmental Sciences 2019年第10期31卷 122-132页

作者： Wenguang Li Xingang Liu yuanhang zhang Qinwen Tan Miao Feng Mengdi Song Lirong Hui Yu Qu Junling An Haokai Gao State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China Chengdu Academy of Environmental Sciences Chengdu 610072 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Environmental monitoring station of Tianjin Port Free Trade Zone Tianjin 300308 China

A severe haze episode occurred in winter in the North China Plain(NCP),and the phenomenon of an explosive growth and sharp decline in PM2.5(particulate matter with an aerodynamic diameter equal to or less than 2.5μm)concentration was *** study the systematic causes for this phenomenon,comprehensive observations were conducted in Beijing from November 26 to December 2,2015;during this period,meteorological parameters,LIDAR data,and the chemical compositions of aerosols were *** haze episode was characterized by rapidly varying PM2.5 concentration,and the highest PM2.5 concentration reached 667μg/*** the haze episode,the NCP was dominated by a weak high-pressure system and continuously low PBL(planetary boundary layer)heights,which are unfavorable conditions for the diffusion of *** large increases in the concentrations of SNA(SO42-,NO3-and NH4+)during the haze implied that the formation of SNA was the largest *** vapor also played a vital role in the formation of haze by promoting the chemical transformation of secondary pollutants,which led to higher PM2.5 *** spatial distributions of PM2.5 in Beijing at different times and the backward trajectories of the air masses also indicated that pollutants from surrounding provinces in particular,contributed to the higher PM2.5concentration.

关键词： Haze episodes Explosive growth Sharp decline Beijing

Exploring atmospheric free-radical chemistry in China:the self-cleansing capacity and the formation of secondary air pollution

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National Science Review 2019年第3期6卷 579-594页

作者： Keding Lu Song Guo Zhaofeng Tan Haichao Wang Dongjie Shang Yuhan Liu Xin Li Zhijun Wu Min Hu yuanhang zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University CAS Center for Excellence in Regional Atmospheric Environment Chinese Academy of Sciences

Since 1971, it has been known that the atmospheric free radicals play a pivotal role in maintaining the oxidizing power of the troposphere. The existence of the oxidizing power is an important feature of the troposphere to remove primary air pollutants emitted from human beings as well as those from the biosphere. Nevertheless, serious secondary air-pollution incidents can take place due to fast oxidation of the primary pollutants. Elucidating the atmospheric free-radical chemistry is a demanding task in the field of atmospheric chemistry worldwide, which includes two kinds of work: first, the setup of reliable radical detection systems; second, integrated field studies that enable closure studies on the sources and sinks of targeted radicals such as OH and NO. In this review, we try to review the Chinese efforts to explore the atmospheric free-radical chemistry in such chemical complex environments and the possible link of this fast gas-phase oxidation with the fast formation of secondary air pollution in the city-cluster areas in China.

关键词： atmospheric chemistry free radicals new particle formations OH NO3