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Significant contribution of carbonyls to atmospheric oxidation capacity(AOC)during the winter haze pollution over North China Plain

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Journal of Environmental Sciences 2024年第5期139卷 377-388页

作者： Xue Yang Gen Zhang Guang Pan Guolan Fan Houyong Zhang Xuan Ge Mingyue Du School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China Shandong Jinan Ecological Environment Monitoring Center Ji’nan 250101China

Atmospheric carbonyl compounds play significant roles in the cycling of radicals and have exhibited surprisingly high levels in winter that were well correlated to particulate matter,for which the reason have not been clearly elucidated.Here we measured carbonyl compounds and other trace gasses together with PM_(2.5)over urban Jinan in North China Plain during the winter.Markedly higher carbonyl concentrations(average:14.63±4.21 ppbv)were found during wintertime haze pollution,about one to three-times relative to those on nonhaze days,with slight difference in chemical composition except formaldehyde(HCHO).HCHO(3.68 ppbv),acetone(3.17 ppbv),and acetaldehyde(CH_3CHO)(2.83 ppbv)were the three most abundant species,accounting for~75% of the total carbonylson both haze and non-haze days.Results from observational-based model(OBM)with atmospheric oxidation capacity(AOC)indicated that AOC significantly increased with the increasing carbonyls during the winter haze events.Carbonyl photolysis have supplied key oxidants such as RO_(2) and HO_(2),and thereby enhancing the formation of fine particles and secondary organic aerosols,elucidating the observed haze-carbonyls inter-correlation.Diurnal variation with carbonyls exhibiting peak values at early-noon and night highlighted the combined contribution of both secondary formation and primary diesel-fuel sources.1-butene was further confirmed to be the major precursor for HCHO.This study confirms the great contribution of carbonyls to AOC,and also suggests that reducing the emissions of carbonyls would be an effective way to mitigate haze pollution in urban area of the NCP region.

关键词： carbonyls Haze Observation-based model Source apportionment Atmospheric oxidation capacity

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Comparison of tailpipe carbonyls and volatile organic compounds emissions from in-use gasoline/CNG bi-fuel vehicles

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Journal of Environmental Sciences 2024年第1期135卷 619-629页

作者： Jiachen Li Yunshan Ge Xin Wang Mengzhu Zhang Haohao Wang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Ground-level ozone contamination has been globally an urban air quality issue,particularly for China,which has recently made significant progress in purifying its sky.Unregulated exhaust emissions from motor vehicles,predominantly carbonyls and volatile organic compounds(VOCs),are among the leading contributors to ozone formation.In this chassislevel study,the unregulated emissions from five China-5 certified gasoline/CNG bi-fuel taxis,along with their ozone forming potential(OFP),were evaluated.It is found that carbonyls and VOCs were mainly emitted during the starting phase no matter the engine was cold or hot.Compared to gasoline,CNG fueling reduced VOCs emissions on a large scale,especially in the starting phase,but had elevated carbonyls.On a fleet average,CNG fueling derived 15%and 46%less OFP than gasoline in cold-and hot-start tests,respectively.VOCs contributed to over 90%of the total OFP of the exhaust.In terms of alleviating ground-level ozone contamination,CNG is a feasible alternative to gasoline on light-duty vehicles.

关键词： CNG Gasoline carbonyls VOCs OFP

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Atmospheric carbonyls in a heavy ozone pollution episode at a metropolis in Southwest China:Characteristics,health risk assessment,sources analysis

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Journal of Environmental Sciences 2022年第3期34卷 40-54页

作者： Jiemeng Bao Hong Li Zhenhai Wu Xin Zhang Hao Zhang Yunfeng Li Jun Qian Junhui Chen Liqun Deng State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Mathematics China University of GeosciencesBeijing 100083China College of Environmental Science and Engineering Shandong UniversityQingdao 266237China Sichuan Academy of Environmental Sciences Chengdu 610000China

Ambient carbonyls were continuously observed in the field during a heavy ozone pollution episode in Chengdu, China from August 4 to August 19, 2019, and the pollution characteristics, atmospheric photochemical reactivity, human health risk, and sources of carbonyls were analyzed. Fifteen carbonyls were quantified with average total mixing ratios of 20.38 ppbv Formaldehyde(9.86 ppbv), acetone(4.41 ppbv), and acetaldehyde(3.57 ppbv) were the three most abundant carbonyls. During the heavy ozone pollution episode, the concentration of carbonyls was found to be higher on pollution days than on the clean days, and relatively higher in the daytime, especially at noon on the pollution days. This was influenced by the intensity of photochemical reactions and precipitation. The “weekend effect” with the concentration of carbonyls was higher on the weekends than on the weekdays was pointed out. Formaldehyde, acetaldehyde and hexaldehyde were the dominant oxidative species during the observation. The carcinogenic and non-carcinogenic risk values of formaldehyde and acetaldehyde were higher on pollution days than on clean days, and these values were higher compared with those of other cities in China and abroad. Long-term exposure to these compounds should therefore be avoided. Diagnostic ratios and correlation analysis together with backward trajectory analysis showed that primary emission and secondary formation accounted 66%-76% and 24%–34% of carbonyls in Chengdu, respectively, with primary emission being the main sources of carbonyls, and carbonyls from the surrounding cities and emission from natural sources also had a significant contribution to the carbonyls in Chengdu.

关键词： carbonyls Pollution characteristics Atmospheric photochemical reactivity Source analysis Chengdu

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Levels,sources and health risks of carbonyls and BTEX in the ambient air of Beijing,China

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Journal of Environmental Sciences 2012年第1期24卷 124-130页

作者： Yujie Zhang Yujing Mu Junfeng Liu Abdelwahid Mellouki Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Centre National de Recherche Scientifique-Institut de Combustion AerothermiqueReactivite et Environnement(CNRS-ICARE)45071 Orleans cedex 02France

The atmospheric concentrations of carbonyls and BTEX （benzene,toluene,ethylbenzene,m,p-xylene and o-xylene） were measured simultaneously at a same sampling site in Beijing from September 2008 to August 2010.The average concentrations of the total measured carbonyls during autumn,winter,spring,and summer were 37.7,31.3,39.7,50.5 μg/m 3,respectively,and maximal values for their diurnal variations usually happened at noontime.In contrast to carbonyls,the average concentrations of the total measured BTEX during the four seasons were 27.2,31.9,23.2,19.1 μg/m 3,respectively,andminimal values for their diurnal variations always occurred in the early afternoon.The average concentration for carbonyls increased about 24% from September 2008–August 2009 to September 2009–August 2010,for BTEX,increased about 15%.Integrated life time cancer risks for three carcinogens （benzene,formaldehyde and acetaldehyde） in Beijing exceeded the value of 1E-06,and the hazard quotient （HQ） of non-cancer risk of exposure to formaldehyde exceeded unity.

关键词： carbonyls BTEX sources exposure and risk assessment Beijing

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Theoretical study on homoleptic mononuclear and binuclear ruthenium carbonyls Ru(CO)_n(n=3―5) and Ru_2(CO)_n(n=8,9)

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Science China Chemistry 2009年第11期52卷 1938-1944页

作者： PENG Bin1,GU FengLong1,ZHANG XiuHui2,LUO Qiong2 & LI QianShu1,2 1 School of Chemistry and Environment,South China Normal University,Guangzhou 510631,China 2 Beijing Institute of Technology,Beijing 100081,China School of Chemistry and Environment South China Normal University Guangzhou China Beijing Institute of Technology Beijing China

Homoleptic mononuclear and binuclear ruthenium carbonyls Ru(CO)n(n=3―5) and Ru2(CO)n(n=8,9) have been investigated using density functional theory.Sixteen isomers are obtained.For Ru(CO)5,the lowest-energy structure is the singlet D3h trigonal bipyramid.Similar to Os(CO)5,the distorted square pyramid isomer with C2v symmetry lies ～7 kJ·mol-1 higher in energy.For the unsaturated mononuclear ruthenium carbonyls Ru(CO)4 and Ru(CO)3,a singlet structure with C2v symmetry and a Cs bent Tshaped structure are the lowest-energy structures,respectively.The global minimum for the Ru2(CO)9 is a singly bridged(CO)4Ru(μ-CO)Ru(CO)4 structure.A triply bridged Ru2(CO)6(μ-CO)3 structure analogous to the known Fe2(CO)9 structure is predicted to lie very close in energy to the global minimum.For Ru2(CO)8,the doubly bridged C2 structure is predicted to be the global minimum.For the lowest-energy structures of M2(CO)n(M=Fe,Ru,Os,n=9,8),it is found that both iron and ruthenium are favored to form structures containing more bridging carbonyl groups,while osmium prefers to have structures with less bridging carbonyl groups.The study of dissociation energy shows that the dissociation of Ru2(CO)9 into the mononuclear fragments Ru(CO)5+Ru(CO)4 is a less energetically demanding process than the dissociation of one carbonyl group from Ru2(CO)9 to give Ru2(CO)8.

关键词： dinuclear ruthenium carbonyls DFT theoretical study

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Unregulated emissions from a diesel engine equipped with vanadium-based urea-SCR catalyst

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Journal of Environmental Sciences 2010年第4期22卷 575-581页

作者： Lei Jiang Yunshan Ge Asad Naeem Shah Chao He Zhihua Liu School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 China. Department of Mechanical Engineering University of Engineering and Technology Lahore 54000 Pakistan School of Transportation Machinery and Civil Engineering Southwest Forestry College Kunming 650224 China

The present work is aimed at the study of number-size distribution of particles, volatile organic compounds （VOCs）, and carbonyl compounds （CC） or carbonyls emitted from a 4-cylinder turbocharged diesel engine equipped with a vanadium-based urea selective catalytic reduction catalyst. The engine was run on an electric dynamometer in accordance with the European steady-state cycle. Pollutants were analyzed using an electric low pressure impactor, a gas chromatograph/mass spectrometer, and a high performance liquid chromatography system for the number-size distribution of particles, VOCs, and CC emissions, respectively. Experimental results revealed that total number of particles were decreased, and their number-size distributions were moved from smaller sizes to larger sizes in the presence of the catalyst. The VOCs were greatly reduced downstream of the catalyst. There was a strong correlation between the conversion of styrene and ethyl benzene. The conversion rate of benzene increased with increase of catalyst temperature. Formaldehyde, acetaldehyde, acrolein and acetone were significantly reduced, resulting in a remarkable abatement in carbonyls with the use of the vanadium-based urea-SCR system.

关键词： diesel engine selective catalytic reduction particulate volatile organic compounds carbonyls

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Regulated and Speciated Hydrocarbon Emissions from a Dual Fuel Light Duty Vehicle with and Without a Three-Way Catalyst

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Journal of Beijing Institute of Technology 2010年第1期19卷 31-36页

作者：丁焰葛蕴珊王军方谭建伟尤可为 School of Mechanical Engineering Beijing Institute of Technology Chinese Research Academy of Environmental Sciences China Automotive Technology & Research Center

The regulated pollutants （CO,HC and NOx） and unregulated pollutants （volatile organic compounds and carbonyl compounds）,emitted from a dual fuel vehicle fueled with gasoline and E10 fuel,are measured under a transient cycle and steady modes.The impacts of a three-way catalyst （TWC） are investigated for the two types of fuels.The measured results show that NOx and acetaldehyde emitted from the E10-fueled car are much more than that from the gasoline-fueled car under the same modes.On the basis of maximum incremental reactivity （MIR） factors and emissions of organic gases,the ozone specific reactivity of the tailpipe gases are evaluated.

关键词： regulated emissions volatile organic compounds （VOCs） carbonyls three-way catalyst （TWC）

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SYNTHESIS AND STRUCTURE ANALYSIS OF CARBONYL HETERONUCLEAR METAL CLUSTER (μ_3-S)FeCoMo(CO)_8(CpCOCH_3)

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Chinese Science Bulletin 1992年第21期37卷 1804-1808页

作者：杨华赵转云殷元骐黄梁仁 Fuzhou Laboratory of Structure Chemistry Academia Sinica Fuzhou 350000 PRC Lanzhou Institute of Chemical Physics Academia Sinica Lanzhou 730000 PRC Fujian Institute of Research on the Structure of Matter Academia Sinica Fuzhou 350002 PRC

Because of the four different elements on the vertexes of tetrahedron, transition metal heteronuclear clusters with tetrahedral structure （μ3-S）FeCoMo（CO）8-x（PPhMe2）（x=1,2） are a series of chiral clusters. Th... 详细信息

关键词： carbonyls heteronuclear cluster chiral complex

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A Cross-Sectional Study on Assessment of Oxidative Stress in Coronary Heart Disease Patients in Bangladesh

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World Journal of Cardiovascular Diseases 2019年第5期9卷 331-342页

作者： Mohammad Kamruzzaman Talita Zahin Choudhury Tania Rahman Laila N. Islam Department of Biochemistry and Molecular Biology University of Dhaka Dhaka Bangladesh

Oxidative stress is considered a central factor in endothelial dysfunction and plaque formation in coronary heart disease (CHD) patients. In this cross-?sectional study, the stress-induced protein and lipid oxidation and production of signaling molecule, nitric oxide has been investigated in CHD patients in Bangladesh. A total of 140 participants were enrolled of which 70 were CHD patients, and the remaining 70 were control subjects having no cardiovascular disease. The diagnosis of CHD was made by expert physicians through characteristic electrocardiogram and troponin changes. The protein carbonyls and thiobarbituric acid reactive substances (TBARS) levels in plasma of both groups were measured by spectrophotometric methods. The plasma nitric oxide levels were measured by reaction with Griess reagent. Statistical non-parametric tests and t-tests were used to analyze the results between the CHD patients and controls. In the patients, the mean protein carbonyls and TBARS, two important markers of oxidative stress, were 2.87 ± 0.97 nmol/mg and 6.92 ± 3.56 nmol/mL, respectively, which were significantly higher than in the control subjects, 1.71 ± 0.82 nmol/mg and 3.15 ± 1.42 nmol/mL, respectively. Assessment of the cardiovascular signaling molecule nitric oxide showed significantly lower value in the CHD patients (6.29 ± 4.78 μM) compared to the controls (10.75 ± 6.03 μM). There was a significant negative correlation between plasma TBARS and total plasma protein, and a weak negative correlation between TBARS and nitric oxide levels in the CHD patients. Evaluation of the smoking habit strongly suggested that smoking was a risk factor for the development of CHD among the Bangladeshi population. These results provide an overview of oxidative?stress-mediated damages on proteins, lipids and effects on signaling molecule nitric oxide in CHD patients.

关键词： Coronary Heart Disease Oxidative Stress TBARS Protein carbonyls Nitric Oxide

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Diurnal and Seasonal Variation of BTX in Ambient air of One Urban Site in Carmen City, Campeche, Mexico

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Journal of Environmental Protection 2013年第8期4卷 40-49页

作者： J. G. Cerón E. Ramírez R. M. Cerón C. Carballo C. Aguilar U. López A. Ramírez Y. Gracia D. Naal A. Campero J. Guerra E. Guevara Facultad de Ciencias Químicas Universidad Autónoma de Nuevo León (UANL) San Nicolás de los Garza Mexico Universidad Autónoma del Carmen Ciudad del Carmen Mexico

BTX (benzene, ethylbenzene, toluene and p-xylene) and meteorological parameters were measured in ambient air of an urban site located in Carmen City, Campeche, Mexico. A total of 412 samples were collected for BTX and analyzed by Gas Chromatography with Flame Ionization Detection (GC-FID). Meteorological parameters were measured by a portable station. A marked diurnal variation was found for all measured BTX. The highest concentrations occurred during midday (13:00-14:30 h). A clear seasonal pattern was observed too for all compounds registering their highest levels during summer sampling period. Mean concentrations for benzene, ethylbenzene, toluene and p-xylene were: 5.42, 3.97, 11.24 and 8.32 ppbv, respectively. BTX abundance showed the following order: toluene > p-xylene > benzene > ethylbenzene. BTX maximum concentrations were found when winds blowed from E and NE. Important oil industry sources and avenues are located at these directions. These sources could contribute to the levels of BTX in this site.

关键词： BTX carbonyls Volatile Organic Compounds Air Pollution Carmen City Mexico

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