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Physicochemical analysis of individual atmospheric fine particles based on effective surface-enhanced Raman spectroscopy

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Journal of environmental Sciences 2019年第1期31卷 388-395页

作者： Zhenli Sun Fengkui Duan Kebin He Jingjing Du Liu Yang Hui Li Tao Ma Shuo Yang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Fine particles associated with haze pollution threaten the health of more than 400 million people in China. It is therefore of great importance to thoroughly investigate and understand their composition. To determine the physicochemical properties in atmospheric fine particles at the micrometer level, we described a sensitive and feasible surface-enhanced Raman scattering(SERS) method using Ag foil as a substrate. This novel method enhanced the Raman signal intensities up to 10,000 a.u. for ν(NO_3^-) in fine *** SERS effect of Ag foil was further studied experimentally and theoretically and found to have an enhancement factor of the order of ～10~4. Size-fractionated real particle samples with aerodynamic diameters of 0.4–2.5 μm were successfully collected on a heavy haze day,allowing ready observation of morphology and identification of chemical components, such as soot, nitrates, and sulfates. These results suggest that the Ag-foil-based SERS technique can be effectively used to determine the microscopic characteristics of individual fine particles, which will help to understand haze formation mechanisms and formulate governance policies.

关键词： SERS PM2.5 Individual particle Atmospheric

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Perfluorocarboxylic acids(PFCAs)and perfluoroalkyl sulfonates(PFASs)in surface and tap water around Lake Taihu in China

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Frontiers of environmental Science & Engineering 2010年第3期4卷 301-310页

作者： Yong QIU He JING Hanchang SHI State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Perfluorinated compounds(PFCs)are ubiquitously distributed in the environment mainly as perfluorocarboxylic acids(PFCAs)and perfluoroalkyl sulfonates(PFASs).In this paper,six PFCAs and two PFASs were quantified in surface and tap water samples from 12 sites around Lake Taihu near Shanghai City in East *** PFCs were perfluorooctanoic acid(PFOA)and perfluorooctane sulfonate(PFOS),of which the concentration ranges were 6.8–206 and 1.2–45 ng·L^(–1),the geometric means were 35.3 and 9.4 ng·L^(–1),and the median(quartile range)values were 31.4(34.4)and 10.4(10.7)ng·L^(–1),*** PFCs were also detected but in much lower concentrations than *** sources of the PFCs were expected to be direct industrial discharges in the Lake Taihu area,and this area was also a possible source of PFCs contaminations in Shanghai district in the *** distributions were found different in the upstream,downstream and north part of Lake *** of PFCs in the tap water in Lake Taihu area indicated their exposure to the local people.A brief estimation of the environmental risks by PFCs implied no acute or immediate risks from PFCs to local human health,but chronic risks from PFOA in the tap water should be considered in the downstream regions.

关键词： surface and tap water perfluorocarboxylic acids(PFCAs) perfluoroalkyl sulfonates(PFASs) Lake Taihu area ultra performance liquid chromatography with tandem mass spectrometry(UPLC-MS)

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"Smoke Detector"of Human Diseases for environmental Aerosol Exposure

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Chinese Journal of Chemistry 2022年第12期40卷 1471-1477,I0002页

作者： Maosheng Yao State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Air consists of various different pollutants(both biological and non-biological).COVID-19 pandemic further threatens the air *** exposure causes many diseases including asthma,respiratory infections and *** protein bi-omarker for early diagnosis often fails due to its lower level at the very beginning of a *** another front,different technologies were attempted for realtime monitoring of air ***,many aerosol exposures occur silently without any knowledge due to limitation of available analytical *** breath has emerged as a promising non-invasive sample for disease diagnosis,in-cluding cancer and *** recently,it was shown that rats emitted distinc-tive profile of volatile organic compounds(VOCs)within minutes when exposed to different air pollutants including ozone and *** the pandemic times,breath-borne VOC was also used to rapidly screen *** exposure could result in changes in metabolism,thus releasing different pat-terns of VOCs via breath within very short *** monitoring of exhaled biomarker profile could spot the early signs of a disease,thus offering an earlier *** array and machine learning together can lend a great hand toward such an *** mini review is undertaken to share such endeavors and inspire further innovations.

关键词： Bioaerosol environmental aerosol exposure Breath biomarkerl Disease Detection Analytical Sensor

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Recent advances in membrane bioreactor technology for wastewater treatment in China

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Frontiers of environmental Science & Engineering 2010年第3期4卷 245-271页

作者： Xia HUANG Kang XIAO Yuexiao SHEN State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Since the introduction of the membrane bioreactor(MBR)in China in the early 1990s,remarkable progress has been achieved on the research and application of this *** has now become one of the most active fields in the world in this *** review outlines the development of MBR-based processes in China and their performance of treating municipal and industrial *** membrane fouling is a critical operational problem with MBR processes,this paper also proposes updated understanding of fouling mechanisms and strategies of fouling control,which are mainly compiled from publications of Chinese *** for the commercial application of MBR in the country,the latest statistics of large-scale MBR plants(>10000 m^(3)·d^(–1))are provided,and the growth trend of total treatment capacity as well as its driving force is analyzed.

关键词： membrane bioreactor(MBR) municipal wastewater treatment industrial wastewater treatment membrane fouling commercial application China

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Intake of tobacco nitrosamines of smokers in various provinces of China and their cancer risk:A meta-analysis

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Journal of environmental Sciences 2024年第7期141卷 249-260页

作者： Xiao Li Zhiwei Ye Jun Wang Pengfei Lin Xiaojin Zhang Shuguang Xie Chao Chen Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhouJiangsu 215163China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Shenzhen Key Laboratory of Organic Pollution Prevention and Control State Key Laboratory of Urban Water Resource and EnvironmentHarbin Institute of TechnologyShenzhen 518055China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Science and EngineeringPeking UniversityBeijing 100871China

Nitrosamines are a class of carcinogens which have been detected widely in food,water,some pharmaceuticals as well as *** objectives of this paper include reviewing the basic information on tobacco consumption and nitrosamine contents,and assessing the health risks of tobacco nitrosamines exposure to Chinese *** searched the publications in English from“Web of Science”and those in Chinese from the“China National Knowledge Infrastructure”in 2022 and collected 151 literatures with valid *** content of main nitrosamines in tobacco,including 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone(NNK),N-nitrosonornicotine(NNN),N-nitrosoanatabine(NAT),N-nitrosoanabasine(NAB),total tobacco-specific nitrosamines(TSNA),and N-nitrosodimethylamine(NDMA)were *** information of daily tobacco consumption of smokers in 30 provinces of China was also ***,the intakes of NNN,NNK,NAT,NAB,TSNAs,and NDMA via tobacco smoke were estimated as 1534ng/day,591 ng/day,685 ng/day,81 ng/day,2543 ng/day,and 484 ng/day by adult smokers in30 provinces,*** cancer risk(CR)values for NNN and NNK inhalation intake were further calculated as 1.44×10^(-5)and 1.95×10^(-4).The CR value for NDMA intake via tobacco smoke(inhalation:1.66×10^(-4))indicates that NDMA is similarly dangerous in tobacco smoke when compared with the *** China,the CR values caused by average nitrosamines intake via various exposures and their order can be estimated as the following:smoke(3.75×10^(-4))>food(1.74×10^(-4))>drinking water(1.38×10^(-5)).Smokers in China averagely suffer 200%of extra cancer risk caused by nitrosamines in tobacco when compared with non-smokers.

关键词： N-nitrosamine Tobacco Cancer risk Tobacco specific nitrosamines(TSNAs) N-nitrosodimethylamine(NDMA)

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Effects of pH on photochemical decomposition of perfluorooctanoic acid in different atmospheres by 185 nm vacuum ultraviolet

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Journal of environmental Sciences 2014年第11期26卷 2207-2214页

作者： Yuan Wang Pengyi Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University School of Chemistry and Chemical Engineering Guizhou University

Perfluorooctanoic acid （PFOA）, a persistent organic pollutant, receives increasing concerns due to its worldwide occurrence and resistance to most conventional treatment processes. The photochemical decomposition by 185 nm vacuum ultraviolet （VUV） is one of the efficient methods for PFOA decomposition. The effects of pH on PFOA decomposition in nitrogen atmosphere or oxygen atmosphere were investigated. At its original pH （4.5） of PFOA aqueous solution, PFOA decomposed efficiently both in nitrogen and in oxygen atmosphere. However, when the pH increased to 12.0, PFOA decomposition was greatly inhibited in oxygen atmosphere, while it was greatly accelerated in nitrogen atmosphere with a very short half-life time （9 rain）. Furthermore, fluorine atoms originally contained in PFOA molecules were almost completely transformed into fluoride ions. Two decomposi- tion pathways have been proposed to explain the PFOA decomposition under different conditions. In acidic and neutral solutions, PFOA predominantly decomposes via the direct photolysis in both atmospheres; while in the alkaline solution and in the absence of oxygen, the decomposition of PFOA is mainly induced by hydrated electrons.

关键词： Perfluorocarboxylic acids (PFCAs)185 nm vacuum ultraviolet Persistent organic pollutants Photochemical Perfluorinated compounds

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Efficient photocatalytic reduction of chromium(Ⅵ) using photoreduced graphene oxide as photocatalyst under visible light irradiation

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Journal of Materials Science & Technology 2021年第32期91卷 17-27页

作者： Mei Yu Jing Shang Yu Kuang Department of Environment and Health State Key Joint Laboratory of Environmental Simulation and Pollution ControlCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Graphene oxide(GO),a new and promising material,has been widely used as a co-catalyst in photocatalytic reactions;however,its capacity as a sole photocatalyst has rarely been *** this study,ultraviolet(UV) light irradiation was used as a modification method to obtain reduced GO(rGO) *** samples were used as photocatalysts to examine their visible light photocatalytic activity toward hexavalent chromium(Cr(Ⅵ)) *** force microscopy(AFM),X-ray diffraction(XRD),UV-vis spectrophotometry,Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and electron spin resonance(ESR) spectroscopy were applied to interpret the surface and structure changes with UV *** oxygen-containing functional groups(OFGs) on the GO surface were reduced to defective carbons andπ-conjugated C=C(sp^(2) domains) under UV light;this led to a decrease in the interlayer distance between GO sheets,GO fragmentation,and increased disorder on the GO *** restoration of sp^(2) domains led to a narrower band gap of GO,which favored the rGO excitation by visible light to generate electron-hole *** rGO pre-irradiated with UV for 1 h(rGO-1),possessing the highest defect density and electron generation efficiency,exhibited the best Cr(Ⅵ) reduction efficiency,which was about three times that of the GO sample;moreover,it outperformed most of the reported GO-based *** addition,low pH and the addition of citric acid as a hole scavenger could further improve the photocatalytic *** study proves that GO or rGO can be used as a sole photocatalyst under visible light to remove environmental pollutants such as heavy-metal ions,and it paves the way for the development of this kind of material and its UV-irradiation modification for further applications.

关键词： Graphene oxide Chromium(Ⅵ) Defect density UV-irradiation modification Photocatalytic reduction

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Discovery of emerging organic pollutants in the atmosphere through an omics approach

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Frontiers of environmental Science & Engineering 2023年第4期17卷 71-81页

作者： Zhen Cheng Xinghua Qiu Xiaodi Shi Xing Jiang Tong Zhu State Key Joint Laboratory for Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringCenter for Environment and HealthPeking UniversityBeijing 100871China

Ambient air pollution,containing numerous known and hitherto unknown compounds,is a major risk factor for public *** discovery of harmful components is the prerequisite for pollution control;however,this raises a great challenge on recognizing previously unknown *** we systematically review the analytical techniques on air pollution in the framework of an omics approach,with a brief introduction on sample preparation and analysis,and in more detail,compounds prioritization and *** high-resolution mass spectrometry(HRMS,typically coupled with chromatography),the complicated environmental matrix can be digitalized into“fullcomponent”data.A key step to discover emerging compounds is the prioritization of compounds from massive *** fingerprints,suspect lists and biological effects are the most vital untargeted strategies for comprehensively screening critical and hazardous ***,compressed data of compounds can be identified at various confidence levels according to exact mass and the derived molecular formula,MS libraries,and authentic *** an omics approach on full-component data provides a paradigm for discovering emerging air pollutants;nonetheless,new technological advancements of instruments and databases are warranted for further tracking the environmental behaviors,hence to evaluate the health risk of key pollutants.

关键词： Air pollution Emerging pollutants Full-component High-resolution mass spectrometry Omics approach

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Determination of Henry's Law constant for methyl hydroperoxide by long path FTIR

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自然科学进展(英文版) 2004年第9期14卷 765-769页

作者： LI Shuang CHEN Zhongming SHI Fei The State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China

Methyl hydroperoxide (MHP, CH3OOH) is one of the main organic peroxides in the atmosphere. In order to understand how MHP partitions in atmospheric gas and liquid phases, the Henry's Law constant for its aqueous solution is determined. A novel technique is established for measuring gas-phase MHP concentration, I.e. The gas phase is collected by a gas-bag and then analyzed by long path Fourier transform infrared (LP-FTIR) spectrometry. At 283 K～303 K, the temperature dependence of the Henry's Law constant for MHP can be expressed as lnKH= a/T - b, a = 4386 ± 140, b = 9.19 ± 0.48, where KH is in unit of molar concentration per atm,and T is in degrees Kelvin. The standard heat of solution is 36.45 ± 1.16 kJ· K- 1· mol-1.

关键词： Henry's Law constant methyl hydroperoxide atmosphere FTIR

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Potential of secondary aerosol formation from Chinese gasoline engine exhaust

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Journal of environmental Sciences 2018年第4期30卷 348-357页

作者： Zhuofei Du Min Hu Jianfei Peng Song Guo Rong Zheng Jing Zheng Dongjie Shang Yanhong Qin He Niu Mengren Li Yudong Yang Sihua Lu Yusheng Wu Min Shao Shijin Shuai State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University State key Laboratory of Automotive Safety and Energy Department of Automotive Engineering Tsinghua University

Light-duty gasoline vehicles have drawn public attention in China due to their significant primary emissions of particulate matter and volatile organic compounds（VOCs）. However,little information on secondary aerosol formation from exhaust for Chinese vehicles and fuel conditions is available. In this study, chamber experiments were conducted to quantify the potential of secondary aerosol formation from the exhaust of a port fuel injection gasoline engine. The engine and fuel used are common in the Chinese market, and the fuel satisfies the China V gasoline fuel standard. Substantial secondary aerosol formation was observed during a 4–5 hr simulation, which was estimated to represent more than 10 days of equivalent atmospheric photo-oxidation in Beijing. As a consequence, the extreme case secondary organic aerosol（SOA） production was 426 ± 85 mg/kg-fuel, with high levels of precursors and OH exposure. The low hygroscopicity of the aerosols formed inside the chamber suggests that SOA was the dominant chemical composition. Fourteen percent of SOA measured in the chamber experiments could be explained through the oxidation of speciated single-ring aromatics. Unspeciated precursors, such as intermediate-volatility organic compounds and semi-volatile organic compounds, might be significant for SOA formation from gasoline VOCs. We concluded that reductions of emissions of aerosol precursor gases from vehicles are essential to mediate pollution in China.

关键词： Port fuel injection Gasoline engine exhaust Secondary aerosol formation Chamber simulation Secondary organic aerosol

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