A5066953708- Atmospheric chemistry and aerosols
- Air Quality and Health Impacts
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Air Quality Monitoring and Forecasting
- Atmospheric aerosols and clouds
- Atmospheric Ozone and Climate
- Quantum Chromodynamics and Particle Interactions
- Vehicle emissions and performance
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Advanced Chemical Sensor Technologies
- Atmospheric and Environmental Gas Dynamics
- Particle Detector Development and Performance
- Remote Sensing and Land Use
- Toxic Organic Pollutants Impact
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Catalytic Processes in Materials Science
- Environmental Changes in China
- COVID-19 impact on air quality
- Remote Sensing in Agriculture
- Analytical Chemistry and Chromatography
- Odor and Emission Control Technologies
- Indoor Air Quality and Microbial Exposure
State Key Joint Laboratory of Environment Simulation and Pollution Control
2016-2025
Peking University
2016-2025
Guizhou University
2025
Northeast Agricultural University
2025
Ministry of Agriculture and Rural Affairs
2025
Nanjing University of Information Science and Technology
2019-2024
Sichuan University
2024
West China Hospital of Sichuan University
2024
Hong Kong Polytechnic University
2012-2023
Xiamen University
2023
Significance We illustrate the similarity and difference in particulate matter (PM) formation between Beijing other world regions. The periodic cycle of PM events is regulated by meteorological conditions. While particle chemical compositions are similar to those commonly measured worldwide, efficient nucleation growth over an extended period distinctive from aerosol typically observed global areas. Gaseous emissions volatile organic compounds nitrogen oxides urban transportation sulfur...
Significance Exceedingly high levels of fine particulate matter (PM) occur frequently in China, but the mechanism severe haze formation remains unclear. From atmospheric measurements two Chinese megacities and laboratory experiments, we show that oxidation SO 2 by NO occurs efficiently aqueous media under polluted conditions: first, during 1952 London Fog via in-cloud oxidation; second, on PM with NH 3 neutralization China. We suggest effective mitigation is achievable intervening sulfate...
Significance Although black carbon (BC) represents a key short-lived climate forcer, its direct radiative forcing remains highly uncertain. The available results from studies of absorption enhancement BC particles during atmospheric aging are conflicting. Using novel environmental chamber method, we have, for the first time to our knowledge, quantified and variation in optical properties under ambient urban conditions representative developed developing countries. Our indicate that polluted...
This study reveals aerosol liquid water content (ALWC) in PM2.5 ranged from 2% up to 74%, and the associated secondary inorganic fraction rose 24% 55%, while ambient relative humidity (RH) increased 15% 83% atmosphere over Beijing. Unexpectedly, with an increase RH, which is a meteorological parameter independent of anthropogenic activities, indicating presence feedback mechanism driven by Henry's law thermodynamic equilibrium. During haze episodes, simultaneously elevated RH levels mass...
Since 1971, it has been known that the atmospheric free radicals play a pivotal role in maintaining oxidizing power of troposphere. The existence is an important feature troposphere to remove primary air pollutants emitted from human beings as well those biosphere. Nevertheless, serious secondary air-pollution incidents can take place due fast oxidation pollutants. Elucidating free-radical chemistry demanding task field worldwide, which includes two kinds work: first, setup reliable radical...
Ambient aerosol samples were collected at an urban site and upwind rural of Beijing during the CAREBEIJING-2008 (Campaigns Air quality REsearch in BEIJING surrounding region) summer field campaign. Contributions primary particles secondary organic aerosols (SOA) estimated by chemical mass balance (CMB) modeling tracer-yield method. The apportioned sources explain 73.8% ± 9.7% 79.6% 10.1% measured OC sites, respectively. Secondary carbon (SOC) contributes to 32.5 15.9% (OC) site, with 17.4...
The heterogeneous hydrolysis of dinitrogen pentoxide (N2O5) is important to understanding the formation particulate nitrate (pNO3–). Measurements N2O5 in surface layer taken at an urban site Beijing are presented here. was observed with large day-to-day variability. High concentrations were determined during pollution episodes co-presence aerosol loads. maximum value 1.3 ppbv (5 s average), associated air mass characterized by a high level O3. uptake coefficients estimated be range...
High levels of ultrafine particles (UFPs; diameter less than 50 nm) are frequently produced from new particle formation under urban conditions, with profound implications on human health, weather, and climate. However, the fundamental mechanisms remain elusive, few experimental studies have realistically replicated relevant atmospheric conditions. Previous simulated oxidation one compound or a mixture compounds, extrapolation laboratory results to chemically complex air was uncertain. Here,...
Abstract. A severe regional haze problem in the megacity Beijing and surrounding areas, caused by fast formation growth of fine particles, has attracted much attention recent years. In order to investigate secondary aging process urban aerosols, four intensive campaigns were conducted seasons between March 2012 2013 at an site (116.31° E, 37.99° N). An Aerodyne high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS) was deployed measure non-refractory chemical components...
Abstract. Nitro-aromatic compounds (NACs), as important contributors to the light absorption by brown carbon, have been widely observed in various ambient atmospheres; however, their formation urban atmosphere was little studied. In this work, we report an intensive field study of NACs summer 2016 at Beijing site, characterized both high-NOx and anthropogenic VOC dominated conditions. We investigated factors that influence NAC (e.g., NO2, precursors, RH photolysis) through quantification...
Abstract. Nitro-aromatic compounds (NACs) were measured hourly at a rural site in China during wintertime to monitor the changes due local and regional impacts of biomass burning (BB). Concurrent continuous measurements concentrations 16 NACs gas particle phases performed with time-of-flight chemical ionization mass spectrometer (CIMS) equipped Filter Inlet for Gases AEROsols (FIGAERO) unit using iodide as reagent ion. accounted <2 % concentration organic matter (OM) total particulate...
NO x and y were determined in the interstitial air of surface snow ambient at Summit, Greenland. levels 3 to >10 times those air, generally greater than levels. [NO ] varied diurnally a manner consistent with photochemical generation within snowpack. These observations imply that reactions occurring or upon ice crystals produced from N‐reservoir compound snow. Average ]:[HNO ]:[NO ratios above elevated relative other remote sites, indicating release snowpack may have altered overlying...
In this study, ultraviolet TOMS (Total Ozone Mapping Spectrometer) satellite data for SO 2 are re‐evaluated the first 15 days following June 1991 Pinatubo eruption to reflect new retrieval and reduction methods. Infrared from TOVS/HIRS/2 (TIROS (Television Observation Satellite) Optical Vertical Sounder/High Resolution Radiation Sounder/2) sensor, whose sets have a higher temporal resolution, also analyzed time Pinatubo. Extrapolation of masses calculated TOVS measurements 19–118 hours after...
Abstract. To characterize aerosol pollution in Beijing, size-resolved aerosols were collected by MOUDIs during CAREBEIJING-2006 field campaign at Peking University (urban site) and Yufa (upwind rural site). Fine particle concentrations (PM1.8 MOUDI) 99.8±77.4 μg/m3 78.2±58.4 μg/m3, with PM1.8/PM10 ratios of 0.64±0.08 0.76±0.08 PKU Yufa, respectively, secondary compounds accounted for more than 50% fine particles. PMF model analysis was used to resolve the modes. Three modes resolved...
Abstract. Aerosol mass spectrometry has proved to be a powerful tool measure submicron particulate composition with high time resolution. Factor analysis of spectra (MS) collected worldwide by aerosol spectrometer (AMS) demonstrates that organic (OA) is usually composed several major components, such as oxygenated (OOA), hydrocarbon-like (HOA), biomass burning (BBOA), and other primary OA. In order help interpretation component MS from factor ambient OA datasets, AMS measurements different...
The Campaigns of Air Quality Research in Beijing and Surrounding Region 2006 (CAREBeijing‐2006) were mainly focused on the influence regional aerosol air pollution Beijing. urban was characterized detail. particle size distributions also compared to those measured at a site (Yufa) approximately 50 km south Peking University (PKU). At PKU, total number volume concentrations (1.8 ± 0.8) × 10 4 cm −3 83.5 57.9 μ m 3 , respectively. Days three consecutive summers 2004, 2005, classified as...
Simultaneous measurements of aerosol size, distribution number, mass, and chemical compositions were conducted in the winter 2007 Beijing using a Twin Differential Mobility Particle Sizer Micro Orifice Uniform Deposit Impactor. Both material density effective ambient particles estimated to be 1.61 ± 0.13 g cm–3 1.62 0.38 for PM1.8 1.73 0.14 1.67 0.37 PM10. Effective decreased nighttime, indicating primary emission from coal burning influenced particles. Size-resolved showed that both values...
Abstract. Organosulfates (OSs) with ambiguous formation mechanisms are a potential source of missing secondary organic aerosol (SOA) in current atmospheric models. In this study, we chemically characterized OSs and nitrooxy-OSs (NOSs) formed under the influence biogenic emissions anthropogenic pollutants (e.g., NOx, SO42−) summer Beijing. An ultrahigh-resolution mass spectrometer equipped an electrospray ionization was applied to examine overall molecular composition S-containing organics....
The molecular composition of humic-like substances (HULIS) in different aerosol samples was analyzed using an ultrahigh-resolution mass spectrometer to investigate the influence biomass burning on ambient composition. HULIS background aerosols were characterized with numerous formulas similar biogenic secondary organic aerosols. abundance nitrogen-containing compounds (NOC), including bases (N-bases) and nitroaromatics, increased dramatically affected by crop residue farm field. distribution...
Abstract. Nocturnal reactive nitrogen compounds play an important role in regional air pollution. Here we present the measurements of dinitrogen pentoxide (N2O5) associated with nitryl chloride (ClNO2) and particulate nitrate (pNO3-) at a suburban site Beijing summer 2016. High levels N2O5 ClNO2 were observed outflow urban masses, 1 min average maxima 937 2900 pptv, respectively. The uptake coefficients, γ, yield, f, experimentally determined from parameters. coefficient ranged 0.012 to...
To elucidate the influence of long-range transported biomass burning organic aerosols (BBOA) on Tibetan Plateau, molecular compositions and light absorption HUmic-Like Substances (HULIS), major fractions brown carbon, were characterized during premonsoon season. Under significant burning, HULIS concentrations increased to as high 26 times background levels, accounting for 54% water-soluble carbon (WSOC) 50% (OC). The also enhanced up 42 contributing 61% WSOC OC absorption. Meanwhile,...
Abstract. A time-of-flight chemical ionization mass spectrometer (CIMS) utilizing the Filter Inlet for Gas and Aerosol (FIGAERO) was deployed at a regional site 40 km north-west of Beijing successfully identified measured 17 sulfur-containing organics (SCOs are organo/nitrooxy organosulfates sulfonates) with biogenic anthropogenic precursors. The SCOs were quantified using laboratory-synthesized standards lactic acid sulfate nitrophenol organosulfate (NP OS). variation in field observations...