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Evolutionary processes and sources of high-nitrate haze episodes over Beijing,Spring

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Journal of Environmental Sciences 2017年第4期29卷 142-151页

作者： Ting Yang Yele Sun Wei Zhang Zifa Wang Xingang Liu pingqing fu Xiquan Wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Aviation Meteorological Center of China Beijing 100021 China State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100089 China

Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an episode that occurred between 15 and 26 April. Submicron aerosol species were found to be substantially elevated during haze episodes, and nitrates showed the largest increase and occupation（average： 32.2%） in non-refractory submicron particles（NR-PM1）, which did not occur in other seasons as previously reported. The haze episode（HE） was divided into three sub-episodes, HEa, HEb, and HEc. During HEa and HEc, a shallow boundary layer, stagnant meteorological conditions, and high humidity favored the formation of high-nitrate concentrations, which were mainly produced by three different processes —daytime photochemical production, gas-particle partitioning, and nighttime heterogeneous reactions — and the decline in visibility was mainly induced by ***, unlike HEa and HEc, during HEb, the contribution of high nitrates was partly from the transport of haze from the southeast of Beijing — the transport pathway was observed at ~800–1000 m by aerosol Lidar —and the decline in visibility during HEb was primarily caused by PM（2.5）. Our results provide useful information for air quality improvement strategies in Beijing during Spring.

关键词： Haze Nitrate Sources Lidar Aerosol Chemical Speciation Monitor Boundary layer

The remarkable but varied photosensitized oxidation by atmospheric humic-like substances at the air-water interface

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Science China Chemistry 2024年第12期67卷 4251-4258页

作者： Ning Yang Chu Gong Dongmei Zhang Xufeng Gao Lifeng Han pingqing fu Xinxing Zhang Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China College of Chemistry Frontiers Science Center for New Organic MatterState Key Laboratory of Advanced Chemical Power SourcesKey Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)Tianjin Key Laboratory of Biosensing and Molecular RecognitionRenewable Energy Conversion and Storage Center(ReCAST)Nankai UniversityTianjin 300071China State Key Laboratory of Component-Based Chinese Medicine Haihe Laboratory of Modern Chinese MedicineTianjin University of Traditional Chinese MedicineTianjin 301617China

Humic-like substances(HULIS),a class of macromolecular photosensitizers,are major components of light-absorbing aerosols in the *** to the amphiphilic nature of HULIS,they tend to appear at the air-water interface of atmospheric ***,there have been limited studies on the photosensitized chemistry of HULIS at the air-water interface owing to the lack of methods with high interface ***,a unique field-induced droplet ionization mass spectrometry(FIDI-MS)technique was used to investigate the photosensitized chemistry of several samples at the air-water *** samples include commercially available humic acid and the PM_(2.5)sample collected during Beijing′s severe winter haze in December ***-resolution Fourier transform-ion cyclotron resonance mass spectrometry(FT-ICR MS)was also applied to analyze the atomic compositions,the degree of unsaturation and the aromaticity of these *** TypeⅠand TypeⅡphotosensitized oxidation pathways were observed,which were postulated to be dictated by the packing density of the molecules at the air-water *** findings reveal that the photosensitization of HULIS at the air-water interface contributes greatly to the formation of atmospheric aerosols,further advancing our understanding of the important roles played by photosensitized chemistry in the atmosphere.

关键词： mass spectrometry humic-like substances photosensitized oxidation air-water interface secondary organic aerosols

Analysis of amino acid enantiomers in ambient aerosols:Effects and removal of coexistent aerosol matrix

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Journal of Environmental Sciences 2024年第3期137卷 732-740页

作者： Ying Li Xiaoying Li Libin Wu Luhan Shi ShanWang pingqing fu Yingyi Zhang Senchao Lai The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China now at Hong Kong University of Science and Technology Hong Kong 00852China

Amino acids(AAs)including D-and L-enantiomers are a group of organic nitrogen species in ambient *** to the low abundances of AAs(level of ng/m^(3))and the matrix effects by coexistent components,it is challenging to quantify AA enantiomers in ambient aerosols especially under pollution *** this study,we present an optimized method for analyzing AA enantiomers in atmospheric aerosol samples including a pretreatment process and the detection by high performance liquid chromatography coupled to a fuorescence detector(HPLC-FLD).Matrix effects caused by coexistent chemicals on AA enantiomers analysis in ambient aerosol samples were investigated especially for those collected in pollution *** results revealed that the determination of AA enantiomers is significantly affected by the coexistent organic carbon(as a proxy of organic matter)and water-soluble ion of NH_(4)^(+).To remove the matrix effects,we applied a pretreatment using the solid phase extraction column coupled with alkaline adjustment to sample *** pretreatment,18 AAs including 6 pairs of D-and L-enantiomers(i.e.,leucine,isoleucine,valine,alanine,serine,and aspartic acid)can be successfully separated and quantified in aerosol samples by *** recoveries are in the range of 67%-106%.This method was successfully applied to the urban aerosol samples from pollution and non-pollution periods for AA enantiomers *** suggest that the concentrations of D-AAs and the ratio of D-AA/L-AA are indicative of the contribution of bacterial sources and the infuence of biomass burning.

关键词： Amino acid enantiomers Atmospheric aerosol Organic carbon Ammonia Chiral ratio

Ultraviolet absorbance titration for the determination of conditional stability constants of Hg(Ⅱ) and dissolved organic matter

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Chinese Journal Of Geochemistry 2008年第1期27卷 46-52页

作者： BAI Yingchen WU Fengchang WAN Guojing LIU Congqiang fu pingqing LI Wen The State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Strong interaction between natural dissolved organic matter (DOM) and Hg(Ⅱ) may influence the trans- port, conversion, toxicity and bio-validity of mercury in the environment. In this paper ultraviolet (UV) absorbance titration was employed for the first time for the determination of the conditional stability constants of Hg(Ⅱ) and (DOM). With increasing Hg(Ⅱ) concentrations, the UV absorbance of fulvic acid, humic acid, and DOM in river increases progressively. By linear and non-linear model fitting, the conditional stability constants (lgK) of Hg(Ⅱ) and DOM were worked out to be 3.54?4.93 and 3.64?4.85, respectively. The results are consistent with those acquired by the typical fluorescence quenching titration method, with the maximum relative error of lgK being 2.6% and the average relative error being 0.2%. The UV absorbance titration method has the advantages of rapid determination, simple performance, and it will probably become a new approach to studying interactions between DOM and trace metallic ions.

关键词：紫外线稳定性汞有机物

Sources, evolution and impacts of EC and OC in snow on sea ice： a measurement study in Barrow, Alaska

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Science Bulletin 2017年第22期62卷 1547-1554页

作者： Tingfeng Dou Cunde Xiao Zhiheng Du J. J. Schauer Hong Ren Baozhu Ge Aihong Xie Jihua Tan pingqing fu Yuanxun Zhang College of Resources and Environment University of Chinese Academy of Sdences Beijing 100049 China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China Environmental Chemistry and Technology Program University of Wisconsin-Madison Madison Wl 53706 USA state Key Laboratory of Atmospheric Boundary Layer Physics-an-d Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Huairou Eco-Environmental Observatory Chinese Academy of Sciences Beijing 101408 China Institute of Surface-Earth System Science Tianjin University Tianjin 300072 China

Based on the field measurements in Barrow, Alaska within the period of April-May 2015, we investigate the sources and variations of elemental carbon(EC) and organic carbon(OC) in the surface layer of snowpack on sea ice, and estimate their effects on the sea ice albedo. Results show that the snow OC in Barrow are from natural sources(e.g. terrestrial higher plants and micro-organisms) mainly, as well as biomass burning(e.g. forest fires and straw combustion) as an important part. Both EC and OC can accumulate at the snow surface with snow melt. The variations in EC and OC and liquid water content in the snow layer are well consistent during the snow-melting period. A higher rate of snow melt implied a more efficient enrichment of EC and OC. In the last phase of snow melt, the concentration increased to a maximum of 16.2 ng/g for EC and 128 ng/g for OC, which is ~10 times larger than those before snow melt onset. Except for the dominant influence of melt amplification mechanism, the variation in concentrations of EC and OC could be disturbed by the air temperature fluctuation and snowfall. Our study indicates that the lightabsorbing impurities contributed 1.6%-5.1% to the reduction in sea ice albedo with melt during the measurement period. The significant period oflight-absorbing impurities influencing on sea ice albedo begins with the rapid melting of overlying snow and ends before the melt ponds formed widely, which lasted for about 10 days in Barrow, 2015.

关键词： Arctic EC OC Sea ice Albedo Barrow

Relationship between fluorescence characteristics and molecular weight distribution of natural dissolved organic matter in Lake Hongfeng and Lake Baihua,China

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Chinese Science Bulletin 2006年第1期51卷 89-96页

作者： YUE Lanxiu WU Fengchang LiU Congqiang LI Wen fu pingqing BAI Yingchen WANG Liying YIN Zuoying Lü Zhicheng State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Shougang Institute of Technology Beijing 100041 China

Dissolved organic matter (DOM) is one of the most interesting and difficult problems in recent years due to its important functions in the ecological and environmental system and the complexity of its chemical composition and structure. It is well ac- cepted that fluorescence characteristics and mo- lecular weight distribution are two important pa- rameters in the DOM characterization. However, the relationship between them is still unknown. In this study, fluorescence and molecular weight distribution of DOM in Lake Hongfeng, Lake Baihua and their rivers, and their relationship were investigated using the combination of fluorescence spectroscopy and high-performance size exclusion chromatography (HPSEC) with on-line UV absorbance and fluores- cence detectors. The results show that there were two obvious humic-like fluorescence peaks (Peaks A and B) in DOM from lake water. But there was an- other obvious protein-like fluorescence peak (Peak C) in DOM from river water. The humic-like fluorescence material consisted of DOM fraction with smaller mo- lecular weight, ranging from 1.0 to 3.0 kDa, while the protein-like fluorescence material mainly consisted of DOM fraction with MW larger than 2.0 kDa. The cal- culation of MW using HPSEC was related to the UV absorbance wavelength chosen.

关键词：荧光性能分子量色谱分析溶解有机物湖泊吸光度

Determination of Hg and MeHg complexation with dissolved organic matter by fluorescence quenching titration

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Chinese Journal Of Geochemistry 2006年第B8期25卷 264-265页

作者： pingqing fu Fengchang WU Feiyue WANG State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Department of Environment and Geography and Department of Chemistry

New insights into the sources and formation of carbonaceous aerosols in China:potential applications of dual-carbon isotopes

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National Science Review 2017年第6期4卷 804-806页

作者： Fang Cao Yanlin Zhang Lujie Ren Junwen Liu Jun Li Gan Zhang Di Liu Yele Sun Zifa Wang Zongbo Shi pingqing fu Yale-NUIST Center on Atmospheric Environment Nanjing University of Information Science and Technology LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Institute of Surface-Earth System Science Tianjin University SKLOG Guangzhou Institute of GeochemistryChinese Academy of Sciences School of Geography Earth and Environmental Sciences University of Birmingham

Carbonaceous aerosols account for20-50%of total fine particulate matter(PM;,particles with a diameter of2.5μm or less)mass concentration in polluted urban atmospheres and can affect atmospheric chemistry,air quality,... 详细信息

关键词： SOA PM New insights into the sources and formation of carbonaceous aerosols in China:potential applications of dual-carbon isotopes

Refractory black carbon aerosols in rainwater in the summer of 2019 in Beijing:Mass concentration,size distribution and wet scavenging ratio

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Journal of Environmental Sciences 2023年第10期132卷 31-42页

作者： Shandong Lei Baozhu Ge Hang Liu Jiannong Quan Danhui Xu Yuting Zhang Weijie Yao Lu Lei Yu Tian Qi Liao Xiaoyong Liu Jie Li Jinyuan Xin Yele Sun pingqing fu Junji Cao Zifa Wang Xiaole Pan State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China National Center for Climate Change Strategy and International Cooperation Ministry of Ecology and EnvironmentBeijing 100035China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100190China

Black carbon(BC)aerosols in the atmosphere play a significant role in climate systems due to their strong ability to absorb solar *** lifetime of BC depends on atmospheric transport,aging and consequently on wet scavenging processes(in-cloud and below-cloud scavenging).In this study,sequential rainwater samples in eight rainfall events collected in 2 mm interval were measured by a tandem system including a single particle soot photometer(SP2)and a *** results showed that the volume-weighted average(VWA)mass concentrations of refractory black carbon(rBC)in each rainfall event varied,ranging from 10.8 to 78.9μg/*** highest rBC concentrations in the rainwater samples typically occurred in the first fraction from individual rainfall *** geometric mean median mass-equivalent diameter(MMD)decreased under precipitation,indicating that rBC with larger sizes was relatively aged and preferentially removed by wet scavenging.A positive correlation(R2=0.73)between the VWA mass concentrations of rBC in rainwater and that in ambient air suggested the important contribution of scavenging ***,the contributions of in-cloud and below-cloud scavenging were distinguished and accounted for 74%and 26%to wet scavenging,*** scavenging ratio of rBC particles was estimated to be 0.06 on *** study provides helpful information for better understanding the mechanism of rBC wet scavenging and reducing the uncertainty of numerical simulations of the climate effects of rBC.

关键词： Refractory black carbon Wet deposition Size distribution