A5021429565- Atmospheric chemistry and aerosols
- Air Quality and Health Impacts
- Atmospheric Ozone and Climate
- Air Quality Monitoring and Forecasting
- Photonic and Optical Devices
- Advanced Photonic Communication Systems
- Advanced Fiber Laser Technologies
- Atmospheric aerosols and clouds
- Optical Network Technologies
- Semiconductor Lasers and Optical Devices
- Photonic Crystals and Applications
- Vehicle emissions and performance
- Optical Coatings and Gratings
- Catalytic Processes in Materials Science
- Advanced Fiber Optic Sensors
- Magnesium Alloys: Properties and Applications
- Atmospheric and Environmental Gas Dynamics
- Water Quality Monitoring and Analysis
- Aluminum Alloys Composites Properties
- Microstructure and mechanical properties
- Cyclone Separators and Fluid Dynamics
- Advanced Optical Network Technologies
- Advanced Chemical Sensor Technologies
- Advanced Photocatalysis Techniques
- Indoor Air Quality and Microbial Exposure
Peking University
2015-2025
ZheJiang Academy of Agricultural Sciences
2022-2025
Huaiyin Institute of Technology
2019-2025
Shanghai University
2022-2025
Chinese Academy of Sciences
2014-2024
Guangzhou Institute of Geochemistry
2020-2024
Shanghai Jiao Tong University
2023-2024
Shanghai Sixth People's Hospital
2023-2024
Jinan University
2020-2024
Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality
2020-2024
Abstract To investigate the seasonal characteristics of submicron aerosol (PM 1 ) in Beijing urban areas, a high‐resolution time‐of‐flight aerosol‐mass‐spectrometer (HR‐ToF‐AMS) was utilized at an site summer (August to September 2011) and winter (November December 2010), coupled with multiple state art online instruments. The average mass concentrations PM (60–84 µg m −3 its chemical compositions different campaigns were relatively consistent recent years. In summer, daily variations stable...
Speciated particle-phase organic nitrates (pONs) were quantified using online chemical ionization MS during June and July of 2013 in rural Alabama as part the Southern Oxidant Aerosol Study. A large fraction pONs is highly functionalized, possessing between six eight oxygen atoms within each carbon number group, not common first generation alkyl previously reported. Using calibrations for isoprene hydroxynitrates measured molecular compositions, we estimate that account 3% 8% total...
Significance Atmospheric fine organic aerosol impacts air quality, climate, and human health. Speciating quantifying the sources of on molecular level improves understanding their formation chemistry hence resulting impacts. Such study, however, has not been possible due to chemical complexity atmospheric aerosol. Here, we provide comprehensive characterization samples from southeastern United States by combining state-of-the-art high-resolution mass spectrometry techniques. We find that...
Abstract. Isoprene emitted by vegetation is an important precursor of secondary organic aerosol (SOA), but the mechanism and yields are uncertain. Aerosol prevailingly aqueous under humid conditions typical isoprene-emitting regions. Here we develop aqueous-phase for isoprene SOA formation coupled to a detailed gas-phase oxidation scheme. The based on reactive uptake coefficients (γ) water-soluble products, including sensitivity acidity nucleophile concentrations. We apply this simulation...
Organic aerosols (OA) in Pasadena are characterized using multiple measurements from the California Research at Nexus of Air Quality and Climate Change (CalNex) campaign. Five OA components identified positive matrix factorization including hydrocarbon‐like (HOA) two types oxygenated (OOA). The elemental composition when plotted as H : C versus O follows a line less steep than that observed for Riverside, CA. OOA both locations follow common line, however, indicating similar secondary...
Abstract Wildfires emit significant amounts of pollutants that degrade air quality. Plumes from three wildfires in the western U.S. were measured aircraft during Studies Emissions and Atmospheric Composition, Clouds Climate Coupling by Regional Surveys (SEAC 4 RS) Biomass Burning Observation Project (BBOP), both summer 2013. This study reports an extensive set emission factors (EFs) for over 80 gases 5 components submicron particulate matter (PM 1 ) these temperate wildfires. These include...
Abstract Brown carbon aerosol consists of light‐absorbing organic particulate matter with wavelength‐dependent absorption. Aerosol optical extinction, absorption, size distributions, and chemical composition were measured in rural Alabama during summer 2013. The field site was well located to examine sources brown aerosol, influence by high biogenic concentrations, pollution from two nearby cities, biomass burning aerosol. We report the closure between dry extinction at 365 nm calculated...
Abstract. Volatile organic compounds (VOCs) were measured by two online instruments (GC-FID/MS and PTR-MS) at a receptor site on Changdao Island (37.99° N, 120.70° E) in eastern China. Reaction with OH radical dominated chemical losses of most VOC species during the campaign. A photochemical-age-based parameterization method is used to calculate emission ratios quantify evolution ambient VOCs. The calculated hydrocarbons agree well those obtained from inventory data, but determined...
Gas-phase low volatility organic compounds (LVOC), produced from oxidation of isoprene 4-hydroxy-3-hydroperoxide (4,3-ISOPOOH) under low-NO conditions, were observed during the FIXCIT chamber study. Decreases in LVOC directly correspond to appearance and growth secondary aerosol (SOA) consistent elemental composition, indicating that condense (at OA below 1 μg m–3). This represents first simultaneous measurement condensing species both gas particle phases. The SOA formation this study is...
Abstract. Organic compounds and liquid water are major aerosol constituents in the southeast United States (SE US). Water associated with inorganic (inorganic water) can contribute to partitioning medium for organic when relative humidities or matter carbon (OM ∕ OC) ratios high such that separation (SRH) below ambient humidity (RH). As OM OC SE US often between 1.8 2.2, experiences both mixing from it. Regional chemical transport model simulations including (but excluding uptake by...
Abstract. Formation of organic nitrates (RONO2) during oxidation biogenic volatile compounds (BVOCs: isoprene, monoterpenes) is a significant loss pathway for atmospheric nitrogen oxide radicals (NOx), but the chemistry RONO2 formation and degradation remains uncertain. Here we implement new BVOC mechanism (including updated isoprene chemistry, monoterpene particle uptake RONO2) in GEOS-Chem global chemical transport model with ∼ 25 × km2 resolution over North America. We evaluate using...
We present measurements as part of the Southern Oxidant and Aerosol Study (SOAS) during which atmospheric aerosol particles were comprehensively characterized. results utilizing a Filter Inlet for Gases AEROsol coupled to chemical ionization mass spectrometer (CIMS). focus on volatility composition isoprene derived organic tracers bulk aerosol. By online molecular information provided by FIGAERO–CIMS, we show that vast majority commonly reported epoxydiol (IEPOX) secondary (SOA) is from...
Abstract. Substantial amounts of secondary organic aerosol (SOA) can be formed from isoprene epoxydiols (IEPOX), which are oxidation products mainly under low-NO conditions. Total IEPOX-SOA, may include SOA other parallel pathways, was quantified by applying positive matrix factorization (PMF) to mass spectrometer (AMS) measurements. The IEPOX-SOA fractions (OA) in multiple field studies across several continents summarized here and show consistent patterns with the concentration gas-phase...
We present results from a high-resolution chemical ionization time-of-flight mass spectrometer (HRToF-CIMS), operated with two different thermal desorption inlets, designed to characterize the gas and aerosol composition. Data field campaigns at forested sites are shown. Particle volatility distributions estimated using three methods: thermograms, elemental formulas, measured partitioning. Thermogram-based consistent those an (AMS) denuder, implying that is reproducible across very...
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...
Acid-driven multiphase chemistry of isoprene epoxydiols (IEPOX), key oxidation products, with inorganic sulfate aerosol yields substantial amounts secondary organic (SOA) through the formation organosulfur compounds. The extent and implications inorganic-to-organic conversion, however, are unknown. In this article, we demonstrate that extensive consumption occurs, which increases IEPOX-to-inorganic concentration ratio (IEPOX/Sulfinorg), as determined by laboratory measurements....
Oxidation flow reactors (OFRs) containing low-pressure mercury (Hg) lamps that emit UV light at both 185 and 254 nm ("OFR185") to generate OH radicals O3 are used in many areas of atmospheric science pollution control devices. The widely potential aerosol mass (PAM) OFR was designed for studies on the formation oxidation secondary organic aerosols (SOA), allowing a wide range oxidant exposures short experiment duration with reduced wall loss effects. Although fundamental photochemical...
<p><strong>Abstract.</strong> Gas- and aerosol-phase measurements of oxidants, biogenic volatile organic compounds (BVOCs) nitrates made during the Southern Oxidant Aerosol Study (SOAS campaign, Summer 2013) in central Alabama show that a nitrate radical (NO<sub>3</sub>) reaction with monoterpenes leads to significant secondary aerosol formation. Cumulative losses NO<sub>3</sub> terpenes are correlated increase gas- aerosol-organic concentrations...
The emergence of parallel convolution-operation technology has substantially powered the complexity and functionality optical neural networks (ONN) by harnessing dimension wavelength. However, this advanced architecture faces remarkable challenges in high-level integration on-chip operation. In work, convolution based on time-wavelength plane stretching approach is implemented a microcomb-driven chip-based photonic processing unit (PPU). To support operation unit, we develop dedicated...
Abstract. Volatile organic compounds (VOCs) play important roles in the tropospheric atmosphere. In this study, VOCs were measured at an urban site Guangzhou, one of megacities Pearl River Delta (PRD), using a gas chromatograph–mass spectrometer/flame ionization detection (GC–MS/FID) and proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS). Diurnal profile analyses show that stronger chemical removal by OH radicals for more reactive hydrocarbons occurs during daytime, which...
Abstract. Anthropogenic secondary organic aerosol (ASOA), formed from anthropogenic emissions of compounds, constitutes a substantial fraction the mass submicron in populated areas around world and contributes to poor air quality premature mortality. However, precursor sources ASOA are poorly understood, there large uncertainties health benefits that might accrue reducing emissions. We show production 11 urban on three continents is strongly correlated with reactivity specific volatile...
Abstract. The atmospheric processes under polluted environments involving interactions of anthropogenic pollutants and natural emissions lead to the formation various complex secondary products. Therefore, characterization oxygenated organic compounds in urban areas remains a pivotal issue our understanding evolution carbon. Here, we describe measurements an iodide chemical ionization time-of-flight mass spectrometer installed with Filter Inlet for Gases AEROsols (FIGAERO-I-CIMS) both gas...
Abstract. Ambient nitrate has been of increasing concern in PM2.5, while there are still large uncertainties quantifying the formation aerosol. The pathways aerosol at an urban site and a suburban Pearl River Delta (PRD) investigated using observation-constrained box model. Throughout campaigns, pollution episodes were constantly accompanied with increase concentrations fractions both sites. simulations demonstrate that chemical reactions daytime night contributed significantly to boundary...
Nowadays, it is challenging to achieve SO2-tolerant environmental catalysis for NOx reduction because of the thermodynamically favorable transformation reactive sites inactive sulfate species in presence SO2. Herein, we enhanced low-temperature by manipulating dynamic coordination environment active sites. Engineered chemistry, SiO2-CeO2 composite oxides with a short-range ordered Ce–O–Si structure were elaborately constructed on TiO2 support. A demonstrated from local low-coordinated...
Abstract. In order to understand the aging and processing of organic aerosols (OA), an intensive field campaign (Campaign Air Pollution at Typical Coastal Areas IN Eastern China, CAPTAIN) was conducted March–April a receptor site (a Changdao island) in central eastern China. Multiple fast aerosol gas measurement instruments were used during campaign, including high resolution time-of-flight mass spectrometer (HR-ToF-AMS) that applied measure concentrations non-refractory chemical components...