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Heterogeneous reactions of SO_2.on ZnO particle surfaces

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Science China Chemistry 2011年第1期54卷 161-166页

作者： li jia,{2. & ZHU tong state key joint laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,Beijing 100871,China 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China

Heterogeneous reactions of SO2.on ZnO particle surfaces were studied using in situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS）. The influences of relative humidity （RH） and UV radiation （2. 365 nm） were investigated. In the absence of UV radiation, sulfite was the prominent product on the particle surfaces, and a negative relationship between RH and sulfite production was observed. In the presence of UV radiation, infrared （IR） absorption of sulfite and sulfate was evident in the spectra. With increasing RH or UV intensity, sulfite was gradually transformed into sulfate. UV intensity and RH exhibited a synergistic effect on the heterogeneous oxidation of SO2.on ZnO. On dry particles and with no UV radiation, the reaction order of SO2.on ZnO particles was 1.6. The initial uptake coefficient for the formation of sulfite, using the Brunauer-Emmett-Teller （BET） area as the reactive surface area of SO2. was 4.87 × 10^-6. At 40% RH and with UV radiation, the reaction order was 0.91, and the initial uptake coefficient was 2.2. ×10^-5.

关键词： SO2 ZnO DRIFTS heterogeneous oxidation UV radiation

Photocatalytic degradation of rhodamine B by dye-sensitized TiO_2.under visible-light irradiation

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Science China Chemistry 2011年第1期54卷 167-172页

作者： shang jing,ZHAO FengWei,ZHU tong & {2. jia state key joint laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,Beijing 100871,China 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China

Perylene tetracarboxylic diimide (PTCDI),widely used in organic photovoltaic devices,is an n-type semiconductor with strong absorption in the visible-light *** has been almost no study of the PTCDI-sensitized TiO2.composite used to photocatalytically degrade *** this study,PTCDIand copper phthalocyanine tetrasulfonic acid (CuPcTs)-sensitized TiO2.composites were prepared using a hydrothermal *** morphologies and structures of the two composites were characterized by X-ray diffraction,transmission electron microscopy,ultraviolet-visible spectroscopy,and fluorescence *** visible-light photocatalytic activities of the composites were evaluated using the degradation of rhodamine B as a model *** showed that dye-sensitized TiO2.samples had a wider absorption spectrum range and higher visiblelight photocatalytic activity compared to TiO2.*** double dye-sensitized (or co-sensitized) TiO2.composite with efficient electron collection exhibited higher photocatalytic activity than did the single dye-sensitized TiO2.*** electron transfer processes of single and double dye-sensitized TiO2.composites were illustrated according to band theory.

关键词： copper phthalocyanine tetrasulfonic acid dye sensitization perylene tetracarboxylic diimide rhodamine B visible-lightphotocatalysis

The roles of heterogeneous chemical processes in the formation of an air pollution complex and gray haze

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Science China Chemistry 2011年第1期54卷 145-153页

作者： ZHU tong,shang jing & ZHAO DeFeng {2. key joint laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,Beijing 100871,China 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China

Urban and regional air pollutions are characterized by high concentrations of secondary pollutants such as photo-oxidants （mainly ozone） and fine particulate matter, which are formed through chemical reactions of the primary pollutants emitted from various sources. The accumulation of these pollutants under stagnant meteorological conditions results in the formation of gray haze, reducing visibility and causing major impacts on human health and climate. In an air pollution complex, the co- existence of high concentrations of primary and secondary gaseous and particulate pollutants provides a large amount of reac- tants for heterogeneous reactions on the surface of fine particles; these reactions change the oxidizing capacity of the atmos- phere, as well as chemical compositions along with the physicochemical and optical properties of particulate matter, thereby accelerating formation of the air pollution complex and gray haze. Using in situ technologies, such as diffuse reflectance infra- red Fourier-transform spectroscopy and single-particle Raman spectroscopy, we systematically investigated the reaction kinet- ics and mechanisms of gaseous pollutants （i.e., NO2. SO2. 03, and formaldehyde） on the surfaces of the major components of atmospheric particles such as CaCO3, kaolinite, montmorillonite, NaC1, sea salt, A12.3, and Tit2. We found that the main re- action products were sulfate, nitrate, or formate, which can change the hygroscopicity and light extinction parameters of those particles significantly. By analyzing the reaction kinetics of these heterogeneous reactions, we identified synergetic mechanisms of the three ternary reaction systems, ,i.e., NOE-particles-H2., SO2.particles-O3, and organics/SO2.particles-UV illumination. These synergetic mechanisms can provide experimental and theoretical bases for understanding the feedback mechanisms and nonlinear processes in the formation of an air pollution complex and gray haze.

关键词： fine particles secondary pollutants oxidizing capacity ternary reaction nonlinear processes

Heterogeneous reaction of formaldehyde on the surface of TiO_2.particles

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Science China Chemistry 2010年第12期53卷 2644-2651页

作者： XU BingYe 1,2.ZHU tong 1,TANG XiaoYan 1 & shang jing 1 1 {2. key joint laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,Beijing 100871,China 2.Zhe{12.ng Province environmental Monitoring Center,Hangzhou 310012.China 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China2. Zhejiang Province Environmental Monitoring Center Hangzhou 310012 China

The heterogeneous reaction of formaldehyde (HCHO) on the surface of titanium dioxide (TiO2. was investigated in situ using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) combined with ion chromatography (IC),X-ray diffraction (XRD),and transmission electron microscopy (TEM).Formate,dioxymethylene,methoxy,and polyoxymethylene were observed in the infrared spectra of TiO2.particles during the *** the surface of TiO2.the adsorbed HCHO was first oxidized to dioxymethylene and further oxidized to *** effects of temperature and ultraviolet radiation (UV) on the reaction products and reactive uptake coefficients were studied,and the results indicate that the reaction rate can be accelerated at increasing temperatures as well as under *** heterogeneous reaction mechanisms of HCHO on the surface of TiO2.in the dark and under UV irradiation are *** measurements show that formate formation on TiO2.is second order in HCHO concentration and the initial reactive uptake coefficients at room temperature calculated with the Brunauer-EmmettTeller specific surface area are (0.5-5) × 10-8 ([HCHO]:1 × 1013-2.× 10 14 molecules/cm3).A linear function relationship exists between the uptake coefficient and the *** apparent activation energy of the reaction was also determined.

关键词： DRIFTS formaldehyde heterogeneous reaction reactive uptake coefficient TiO2

Hydroxyl radicals induced by quartz particles in lung alveolar macrophages: the role of surface iron

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Progress in Natural Science:Materials International 2006年第10期16卷 1038-1044页

作者： li Yi, ZHU tong, GUO Xinbiao and {2. Yu ( state key joint laboratory for environmental simulation & pollution control, Peking University, Beijing 100871, China Occupational & environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100083, China) [a]state key {2. laboratory for environmental simulation & pollution control Peking University Beijing China [b]Occupational & environmental Health Sciences School of Public Health Peking University Health Science Center Beijing China

Previous studies have shown that hydroxyl radical generation is a key step in the mechanism of pathogenic process caused by airborne particles to the lung. However, there is no direct evidence for dose-response relationship between airborne particles and hydroxyl radical generation. In this study, hydroxyl radicals generated in lung alveolar macrophages exposed to quartz particles were measured using a highly sensitive capillary electrophoresis-fluorescence detection method. The results demonstrated that quartz particles induced the generation of hydroxyl radical in a dose-dependent manner, and the amount of the hydroxyl radicals was 10-10 mol/10 cells. The viability of alveolar macrophages exposed to quartz particles decreased with the increase of quartz concentration, showing a clear dose-response relationship. Hydroxyl radical scavenger mannitol could increase the viability of quartz-treated cells, suggesting that hydroxyl radical contributed directly to cell death. In this study this contribution accounted for about 5%-2.% of cell death. The hydroxyl radical generating potential was found to be related to surface iron content of the quartz particles.

关键词： inhalable quartz hydroxyl radical capillary electrophoresis dose-response relationship iron.

Heterogeneous reaction of NO_2.with sea salt particles

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Science China Chemistry 2010年第12期53卷 2652-2656页

作者： YE ChunXiang 1,li HongJun 1,ZHU tong 1,{2. 1,ZHANG ZeFeng 1,2.& ZHAO DeFeng 1 1 state key joint laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,Bei{12. 100871,China 2.College of Atmospheric Physics,Nan{12. University of Information Science and Technology,Nan{12. 2.0044,China 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China2. College of Atmospheric Physics Nanjing University of Information Science and Technology Nanjing 210044 China

To understand how NO2.reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2.on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2.concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.2. × 10-6 respectively under 0% and 2.% relative humidity (RH) at NO 2.molecular concentration of 1.96 × 1015 mol/*** results showed that liquid water was formed at the site of MgCl2.6H2.,CaCl2.2.2. on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.

关键词： sea salt particles diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) hydrated water absorbed water reactive uptake coefficient

Heterogeneous oxidation of SO_2.by O_3-aged black carbon and its dithiothreitol oxidative potential

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Journal of environmental Sciences 2015年第10期27卷 56-62页

作者： Weiwei Xu Qian li jing {2. jia liu Xiang Feng tong Zhu state key {2. laboratory of environmental simulation and pollution control College of Environmental Sciences and EngineeringPeking University POTEN Environment Group Co. Ltd.

Ozone（O3） is an important atmospheric oxidant. Black carbon（BC） particles released into the atmosphere undergo an aging process via O3 oxidation. O3-aged BC particles may change their uptake ability toward trace reducing gases such as SO2.in the atmosphere,leading to different environmental and health effects. In this paper, the heterogeneous reaction process between O3-aged BC and SO2.was explored via in-situ diffuse reflectance infrared Fourier transform spectroscopy（DRIFTS）. Combined with ion chromatography（IC）,DRIFTS was used to qualitatively and quantitatively analyze the sulfate product. The results showed that O3-aged BC had stronger SO2.oxidation ability than fresh BC, and the reactive species/sites generated on the surface had an important role in the oxidation of *** humidity or 2.4 nm UV（ultraviolet） light illumination enhanced the oxidation uptake of SO2.on O3-aged BC. The oxidation potentials of the BC particles were detected via dithiothreitol（DTT） assay. The DTT activity over BC was decreased in the process of SO2.reduction, with the consumption of oxidative active sites.

关键词： Black carbon Ozone SO2.Heterogeneous reaction Oxidative potential Dithiothreitol assay

Heterogeneous reaction of NO_2.on the surface of montmorillonite particles

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Journal of environmental Sciences 2012年第10期24卷 1753-1758页

作者： Zefeng Zhang jing shang {2. Zhu Hongjun li Defeng Zhao Yingju liu Chunxiang Ye College of environmental Sciences and Engineering Peking UniversityBeijing 100871China CMA key laboratory for Atmospheric Physics and Environment Nanjing University of Information Science and TechnologyNanjing 210044China

The studies on heterogeneous reactions over montmorillonite, which is a typical 2.1 layered aluminosilicate, will benefit to the Understanding of heterogeneous reactions on clay minerals. Montmorillonite can be classified as sodium montmorillonite or calcium montmorillonite depending on the cation presented between the different layers. Using diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS）, the heterogeneous reaction mechanism of NO2.on the surface of montmorillonite was firstly investigated. Results showed that the reaction of NO2.on the surface of sodium and calcium montmorillonite fit a first-order kinetics, and the reaction duration of calcium montmorillonite was longer than that of sodium montmorillonite under the dry condition. For either sodium or calcium montmorillonite, the uptake coefficient decreased as humidity increased.

关键词： heterogeneous reaction uptake coefficient DRIFTS montmorillonite NO2

Sources of ambient non-methane hydrocarbon compounds and their impacts on O_(3) formation during autumn,Beijing

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Journal of environmental Sciences 2022年第4期34卷 85-97页

作者： Fangjie li Shengrui tong Chenhui {2. Xinran Zhang Deng lin Wenqian Zhang Weiran li lili Wang Maofa Ge lixin Xia College of Chemistry Liaoning UniversityShenyang 110036China state key {2. for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China key laboratory of Oasis Ecology College of Resource and Environment SciencesXinjiang UniversityUrumqi 830046China state key {2. of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China Department of Chemical and environmental Engineering Yingkou Institute of TechnologyYingkou 115014China

The field observation of 54 non-methane hydrocarbon compounds(NMHCs)was conducted from September 1 to October 2. in 2.2. during autumn in Haidian District,*** mean concentration of total NMHCs was 2..81±11.39 ppbv during this period,and alkanes were the major *** were typical festival effects of NMHCs with lower concentration during the National *** and aromatics were the dominant groups in ozone formation potential(OFP)and OH radical loss rate(L_(OH)).The positive matrix factorization(PMF)running results revealed that vehicular exhaust became the biggest source in urban areas,followed by liquefied petroleum gas(LPG)usage,solvent usage,and fuel *** box model coupled with master chemical mechanism(MCM)was applied to study the impacts of different NMHCs sources on ozone(O_(3))formation in an O_(3)*** {2. results indicated that reducing NMHCs concentration could effectively suppress O_(3)***,reducing traffic-related emissions of NMHCs was an effective way to control O_(3)pollution at an urban site in Beijing.

关键词： Non-methane hydrocarbon compounds Festival effects Ozone Source apportionment Master chemical mechanism