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Characterizing oxygenated volatile organic compounds and their sources in rural atmospheres in China

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Journal of Environmental Sciences 2019年第7期31卷 148-155页

作者： Yu Han Xiaofeng Huang Chuan Wang Bo Zhu lingyan he Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Oxygenated volatile organic compounds(OVOCs) are important precursors and products of atmospheric secondary pollution. The sources of OVOCs, however, are still quite uncertain,especially in the atmosphere with much pollution in China. To study the sources of OVOCs in rural atmospheres, a proton transfer reaction mass spectrometry(PTR-MS) was deployed at a northern rural site(WD) and a southern rural site(YMK) in China during the summer of 2014 and 2016, respectively. The continuous observation showed that the mean concentration of TVOCs(totally 17 VOCs) measured at WD(52.4 ppbv) was far higher than that at YMK(11.1 ppbv), and the OVOCs were the most abundant at both the two sites. The diurnal variations showed that local sources of OVOCs were still prominent at WD, while regional transport influenced YMK much. The photochemical age-based parameterization method was then used to quantitatively apportion the sources of ambient OVOCs. The anthropogenic primary sources at WD and YMK contributed less(2%–16%) to each OVOC species. At both the sites, the atmospheric background had a dominant contribution(～ 50%) to acetone and formic acid, while the anthropogenic secondary formation was the main source(～ 40%) of methanol and MEK. For acetaldehyde and acetic acid, the biogenic sources were their largest source(～ 40%) at WD, while the background(39%) and anthropogenic secondary formation(42%) were their largest sources at YMK, respectively. This study reveals the complexity of sources of OVOCs in China, which urgently needs explored further.

关键词： OVOCs Photochemical age Anthropogenic sources Primary emission Secondary formation

Development of an on-line measurement system for water-soluble organic matter in PM_(2.5) and its application in China

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Journal of Environmental Sciences 2018年第7期30卷 33-40页

作者： Huiying Li Xiaofeng Huang Liming Cao Yuhong Zhai Liwu Zeng lingyan he Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Water-soluble organic matter（WSOM） represents a critical fraction of fine particles（PM2.5）in the air, but its changing behaviors and formation mechanisms are not well understood yet, partly due to the lack of fast techniques for the ambient measurements. In this study,a novel system for the on-line measurement of water-soluble components in PM2.5, the particle-into-liquid sampler（PILS）–Nebulizer–aerosol chemical speciation monitor（ACSM）, was developed by combining a PILS, a nebulizer, and an ACSM. High time resolution concentrations of WSOM, sulfate, nitrate, ammonium, and chloride, as well as mass spectra, can be obtained with satisfied quality control results. The system was firstly applied in China for field measurement of WSOM. The mass spectrum of WSOM was found to resemble that of oxygenated organic aerosol, and WSOM agreed well with secondary inorganic ions. All evidence collected in the field campaign demonstrated that WSOM could be a good surrogate of secondary organic aerosol（SOA）. The PILS–Nebulizer–ACSM system can thus be a useful tool for intensive study of WSOM and SOA in PM2.5.

关键词： PM2.5 Water-soluble organic matter Secondary organic matter On-line measurement Mass spectrum

Complete entanglement analysis on electron spins using quantum dot and microcavity coupled system

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Science China(Physics,Mechanics & Astronomy) 2013年第11期56卷 2054-2058页

作者： WANG Chuan he lingyan ZHANG Yong MA HaiQiang ZHANG Ru School of Science Beijing University of Posts and Telecommunications State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

We present an entanglement analysis protocol on entangled electron spins using quantum dot(QD)and microcavity coupled *** quantum dot is placed in the microcavity and ancilla photon input-output process could be used to check the parity of the quantum *** the parity check process,the user only needs to measure the spin direction of the QD spin,and the state information can be readout *** feasibility of our scheme and the experimental challenge are discussed by considering currently available techniques.

关键词： entanglement analysis quantum dot microcavity

Characterization of submicron aerosols in the urban outflow of the central Pearl River Delta region of China

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 725-733页

作者： Zhaoheng GONG Zijuan LAN Lian XUE Liwu ZENG lingyan he Xiaofeng HUANG Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China Qingdao Environmental Monitoring Center Qingdao 266003China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control School of Environmental Sciences and EngineeringNanjing University of Information Sciences and EngineeringNanjing 210044China

Submicron aerosol particles （with aerody- namic diameters less than 1 pm, PM1） were sampled and measured in heshan, an urban outflow site of Guangzhou megacity in Pearl River Delta in South China, using an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer （HR-ToF-AMS） in November 2010 during 2010 Guangzhou Asian Games. The mean PM~ mass concentration measured was 47.9 ± 17.0 μg.m3 during the campaign, with organic aerosol （OA） and sulfate being the two dominant species, accounting for 36.3% and 20.9% of the total mass, respectively, followed by black carbon （17.1%, measured by an aethalometer）, nitrate （12.9%）, ammonium （9.6%） and chloride （3.1%）. The average size distributions of the species （except black carbon） were dominated by an accumulation mode peaking at -550 nm. Calculations based on high-resolution organic mass spectrum showed that, C, H, O and N on average contributed 58.1%, 7.3%, 30.7%, and 3.9% to the total organic mass, respectively. The average ratio of organic mass over organic carbon mass （OM/OC） was 1.73 ± 0.08. Four components of OA were identified by the Positive Matrix Factorization （PMF） analysis, including a hydro- carbon-like （HOA）, a biomass burning （BBOA） and two oxygenated （SV-OOA and LV-OOA） organic aerosol components, which on average accounted for 18.0%, 14.3%, 28.8% and 38.9% of the total organic mass, respectively.

关键词： organic aerosol high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) positive matrix factorization

Chemical characterization and source apportionment of atmospheric submicron particles on the western coast of Taiwan Strait, China

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Journal of Environmental Sciences 2017年第2期29卷 293-304页

作者： Liming Cao Qiao Zhu Xiaofeng Huang Junjun Deng Jinsheng Chen Youwei Hong Lingling Xu lingyan he Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences

Taiwan Strait is a special channel for subtropical East Asian Monsoon and its western coast is an important economic zone in China. In this study, a suburban site in the city of Xiamen on the western coast of Taiwan Strait was selected for fine aerosol study to improve the understanding of air pollution sources in this region. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer（HR-To F-AMS） and an Aethalometer were deployed to measure fine aerosol composition with a time resolution of 5 min from May 1to 18, 2015. The average mass concentration of PM1 was 46.2 ± 26.3 μg/m^3 for the entire campaign. Organics（28.3%）, sulfate（24.9%）, and nitrate（20.6%） were the major components in the fine particles, followed by ammonium, black carbon（BC）, and chloride. Evolution of nitrate concentration and size distribution indicated that local NOx emissions played a key role in high fine particle pollution in Xiamen. In addition, organic nitrate was found to account for 9.0%–13.8% of the total measured nitrate. Positive Matrix Factorization（PMF）conducted with high-resolution organic mass spectra dataset differentiated the organic aerosol into three components, including a hydrocarbon-like organic aerosol（HOA） and two oxygenated organic aerosols（SV-OOA and LV-OOA）, which on average accounted for 27.6%,28.8%, and 43.6% of the total organic mass, respectively. The relationship between the mass concentration of submicron particle species and wind further confirmed that all major fine particle species were influenced by both strong local emissions in the southeastern area of Xiamen and regional transport through the Taiwan Strait.

关键词： Submicron particle Chemical characterization Organic aerosol Source apportionment

Understanding primary and secondary sources of ambient oxygenated volatile organic compounds in Shenzhen utilizing photochemical age-based parameterization method

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Journal of Environmental Sciences 2019年第1期31卷 105-114页

作者： Bo Zhu Yu Han Chuan Wang Xiaofeng Huang Shiyong Xia Yingbo Niu Zixuan Yin lingyan he Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Oxygenated volatile organic compounds(OVOCs) are key intermediates in the atmospheric photooxidation process. To further study the primary and secondary sources of OVOCs,their ambient levels were monitored using a proton-transfer reaction mass spectrometer(PTR-MS) at an urban site in the Pearl River Delta of China. Continuous monitoring campaigns were conducted in the spring, summer, fall, and winter of 2016. Among the six types of OVOC species, the mean concentrations of methanol were the highest in each season(up to 13–20 ppbv), followed by those of acetone, acetaldehyde and acetic acid(approximately 2–4 ppbv), while those of formic acid and methyl ethyl ketone(MEK) were the lowest(approximately 1–2 ppbv). As observed from a diurnal variation chart, the OVOCs observed in Shenzhen may have been affected by numerous factors such as their primary and secondary sources and photochemical consumption. The photochemical age-based parameterization method was used to apportion the sources of ambient OVOCs. Methanol had significant anthropogenic primary sources but negligible anthropogenic secondary sources during all of the seasons. Acetone, MEK and acetic acid were mostly attributed to anthropogenic primary sources during each season with smaller contributions from anthropogenic secondary sources. Acetaldehyde had similar contributions from both anthropogenic secondary and anthropogenic primary sources throughout the ***, anthropogenic primary sources contributed the most to formic acid.

关键词： OVOCs PTR-MS Photochemical age-based parameterization method

Source apportionment of PM_(2.5)light extinction in an urban atmosphere in China

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Journal of Environmental Sciences 2018年第1期30卷 277-284页

作者： Zijuan Lan Bin Zhang Xiaofeng Huang Qiao Zhu Jinfeng Yuan Liwu Zeng Min Hu lingyan he Key Laboratory for Urban Habitat Enuironmental Science and Technology School of Enuironment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China Shenzhen Research Academy of Environmental Sciences Shenzhen 518001China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Haze in China is primarily caused by high pollution of atmospheric fine particulates（PM2.5）.However, the detailed source structures of PM2.5 light extinction have not been well established, especially for the roles of various organic aerosols, which makes haze management lack specified targets. This study obtained the mass concentrations of the chemical compositions and the light extinction coefficients of fine particles in the winter in Dongguan, Guangdong Province, using high time resolution aerosol observation instruments. We combined the positive matrix factor（PMF） analysis model of organic aerosols and the multiple linear regression method to establish a quantitative relationship model between the main chemical components, in particular the different sources of organic aerosols and the extinction coefficients of fine particles with a high goodness of fit（R^2= 0.953）. The results show that the contribution rates of ammonium sulphate,ammonium nitrate, biomass burning organic aerosol（BBOA）, secondary organic aerosol（SOA） and black carbon（BC） were 48.1%, 20.7%, 15.0%, 10.6%, and 5.6%, respectively. It can be seen that the contribution of the secondary aerosols is much higher than that of the primary aerosols（79.4% versus 20.6%） and are a major factor in the visibility decline. BBOA is found to have a high visibility destroying potential, with a high mass extinction coefficient, and was the largest contributor during some high pollution periods. A more detailed analysis indicates that the contribution of the enhanced absorption caused by BC mixing state was approximately 37.7% of the total particle absorption and should not be neglected.

关键词： Fine particles Organic aerosol Positive matrix factorisation Light extinction Multiple linear regression

Characterization of particle number size distribution and new particle formation in Southern China

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Journal of Environmental Sciences 2017年第1期29卷 342-351页

作者： Xiaofeng Huang Chuan Wang Jianfei Peng lingyan he Liming Cao Qiao Zhu Jie Cui Zhijun Wu Min Hu Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Knowledge of particle number size distribution（PND） and new particle formation（NPF）events in Southern China is essential for mitigation strategies related to submicron particles and their effects on regional air quality,haze,and human *** this study,seven field measurement campaigns were conducted from December 2013 to May 2015 using a scanning mobility particle sizer（SMPS） at four sites in Southern China,including three urban sites and one background *** were measured in the size range of15-515 nm,and the median particle number concentrations（PNCs） were found to vary in the range of 0.3× 10~4-2.2 × 10~4 cn^（-3） at the urban sites and were approximately 0.2 × 10~4 cm^（-3） at the background *** peak diameters at the different sites varied largely from 22 to 102 *** PNCs in the Aitken mode（25-100 nm） at the urban sites were up to 10 times higher than they were at the background site,indicating large primary emissions from traffic at the urban *** diurnal variations of PNCs were significantly influenced by both rush hour traffic at the urban sites and NPF *** frequencies of NPF events at the different sites were0%-30%,with the highest frequency occurring at an urban site during *** higher SO_2 concentrations and higher ambient temperatures being necessary,NPF at the urban site was found to be more influenced by atmospheric oxidizing capability,while NPF at the background site was limited by the condensation *** study provides a unique dataset of particle number and size information in various environments in Southern China,which can help understand the sources,formation,and the climate forcing of aerosols in this quickly developing region,as well as help constrain and validate NPF modeling.

关键词： Scanning mobility particle sizer(SMPS) Particle number size distribution(PND) New particle formation(NPF) Air pollution Southern China

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深圳大气中甲酸的季节变化和来源解析

环境科学学报 2024年第9期44卷 1-9页

作者：陆骏铭曹礼明焦伯旸李志杰姜震何凌燕黄晓锋北京大学深圳研究生院环境与能源学院大气观测超级站实验室深圳518055

近年来,我国PM_(2.5)浓度逐年下降,而O_(3)污染问题愈发突出,并已成为深圳市乃至珠三角地区的首要大气污染物.挥发性有机物(VOCs)的光化学氧化是O_(3)生成的最主要途径,而甲酸(HCOOH)是大气中一种典型的光化学产物,其生成途径涉及多种V... 详细信息

近年来,我国PM_(2.5)浓度逐年下降,而O_(3)污染问题愈发突出,并已成为深圳市乃至珠三角地区的首要大气污染物.挥发性有机物(VOCs)的光化学氧化是O_(3)生成的最主要途径,而甲酸(HCOOH)是大气中一种典型的光化学产物,其生成途径涉及多种VOCs前体物及大气氧化剂,与臭氧污染密切相关.本研究使用化学电离质谱(CIMS),于2022年10月-2023年9月对深圳市大气甲酸进行了为期1年的在线测量,分析了其日变化和季节特征,并通过相关性分析和光化学龄参数化法评估其主要的来源.观测结果表明,深圳市大气甲酸在干季和湿季的平均浓度分别为3.1μg·m^(-3)和2.5μg·m^(-3)(1h平均),并在干季与O_(3)浓度有较强的正相关性.进一步分析表明,甲酸的来源主要为光化学反应的二次生成,天然源的贡献最大,其次为人为二次源和背景,人为一次源和生物质燃烧源的贡献很小.本研究显示天然源排放对深圳大气光化学反应具有重要作用.

关键词：大气甲酸臭氧光化学反应季节变化源解析