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Evaluation of offline sampling for atmospheric C3-C11 non-methane hydrocarbons

Journal of Environmental Sciences 2022年第3期34卷 132-140页

作者： Zhiguo Liu Chengtang Liu Zhouming He yujing mu Chenglong Zhang Yuanyuan Zhang Pengfei Liu Yuzheng Wang Junfeng Liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Center for Excellence in Urban Atmospheric Environment Institute of Regional EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Clear Science&Technology Co. LtdBeijing 100029China

The concentration variation of C3-C11 non-methane hydrocarbons(NMHCs)collected in several types of commercial flexible bags and adsorption tubes was systematically inves-tigated using a gas chromatography-flame ionization detector(GC-FID)*** per-centage loss of each NMHC in the polyvinyl fluoride(PVF)bags was less than 5%during a 7-hr storage period;significant NMHCs loss was detected in aluminum foil composite film and fluorinated ethylene propylene *** thermal desorption efficiency of NMHCs for adsorption tubes filled Carbopack B and Carboxen1000 sorbents was greater than 95%at 300℃,and the loss of NMHCs in the adsorption tubes during 20-days storage at 4℃was less than 8%.The thermal desorption efficiency for C11 NMHCs in the adsorption tube filled with Carbograph 1 and Carbosieve SⅢabsorbents was less than 40%at 300℃,and pyrolysis of the absorbents at 330℃interfered significantly with the measurements of some *** loss of alkenes was significant when NMHCs were sampled by cryo-enrichment at-90℃in the presence of O3 for the online NMHC measurements,and negligible for enrichment us-ing adsorption tubes at 25℃.Although O_(3)scrubbers have been widely used to eliminate the influence of O_(3)on NMHC measurements,the loss of NMHCs with carbon numbers greater than 8 was more than 10%.Therefore,PVF bags and adsorption tubes filled Carbopack B and Carboxen1000 sorbents were recommended for the sampling of atmospheric NMHCs.

关键词： Non-methane hydrocarbons(NMHCs) Gas chromatography-flame ionization detector(GC-FID) Offline sampling Adsorption tubes Ozone scrubber

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基于CiteSpace的眼眶炎性假瘤的可视化分析

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中国医药导报 2024年第6期21卷 8-14页

作者：翟孟凡谢立科郝晓凤莫雅婷穆玉晶中国中医科学院眼科医院内障眼病2科北京100040 中国中医科学院眼科医院目系眼病科北京100040 北京中医药大学东直门医院普外科北京100007

目的基于CiteSpace可视化分析眼眶炎性假瘤国内外研究现状,以期为其临床诊治提供借鉴。方法通过分别检索1990年1月至2022年12月中国知网及Web of Science核心合集数据库收录的相关文献,使用CiteSpace软件对作者、研究机构、关键词等... 详细信息

目的基于CiteSpace可视化分析眼眶炎性假瘤国内外研究现状,以期为其临床诊治提供借鉴。方法通过分别检索1990年1月至2022年12月中国知网及Web of Science核心合集数据库收录的相关文献,使用CiteSpace软件对作者、研究机构、关键词等进行可视化分析。结果最终收入中文文献218篇、英文文献628篇,中英文文献年发文量呈逐年上升趋势,中文文献形成了以马建民、颜建华为中心的数个作者群,英文文献主要形成了以Garrity JA、Civit T等为核心的团队;国内外研究机构集中在高校及其附属医院,机构间合作比较分散;中文高频关键词有炎性假瘤、眼眶、特发性等,英文高频关键词pseudotumor、orbital pseudotumor、disgnosis等;中英文热点关键词形成均9个聚类群。结论近30年来,国内外对眼眶炎性假瘤的研究呈上升趋势,研究热点已从临床症状和诊断方法的研究逐渐转至发病机制及治疗方法的研究,并取得一定成果。

关键词： CiteSpace 眼眶炎性假瘤可视化分析

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An improved GC-ECD method for measuring atmospheric N_2O

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Journal of Environmental Sciences 2013年第3期25卷 547-553页

作者： Yuanyuan Zhang yujing mu Shuangxi Fang Junfeng Liu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Key Laboratory for Atmospheric Chemistry Centre for Atmosphere Watch and ServicesChinese Academy of Meteorological Sciences

Gas chromatography equipped with an electron capture detector （GC-ECD） has been widely used for measuring atmospheric N2O,but nonlinear response and the influence of atmospheric CO2 have been recognized as defects for *** original GCECD method using N 2 as carrier gas was improved by introducing a small flow rate of CO2 makeup gas into the ECD,which could well remedy the above *** N2O signal of the improved method was 4-fold higher than that of the original method and the relative standard deviation was reduced from 〉 1% to 0.31%.N2O concentrations with different CO2 concentrations （172.2×10-6-1722×10-6mol/mol） measured by the improved GC-ECD method were in line with the actual N2O ***,the N2O concentrations detected by the original method were largely biased with a variation range of-4.5%～7%.The N2O fluxes between an agricultural field and the atmosphere measured by the original method were greatly overestimated in comparison with those measured by the improved *** linear correlation （R2=0.9996） between the response of the improved ECD and N2O concentrations （93×10-9-1966×10-9mol/mol） indicated that atmospheric N2O could be accurately quantified via a single standard *** N2O concentrations comparatively measured by the improved method and a high precision GC-ECD method were in good agreement.

关键词： N2O GC-ECD CO2 exchange flux method comparison

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Impact of dicyandiamide on emissions of nitrous oxide,nitric oxide and ammonia from agricultural field in the North China Plain

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Journal of Environmental Sciences 2016年第2期28卷 20-27页

作者： Yizhen Zhou Yuanyuan Zhang Di Tian yujing mu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China

Nitrous oxide（N_2O）, nitric oxide（NO） and ammonia（NH_3） emissions from an agricultural field in the North China Plain were compared for three treatments during a whole maize growing period from 26 June to 11 October, 2012. Compared with the control treatment（without fertilization, designated as CK）, remarkable pulse emissions of N_2O, NO and NH_3 were observed from the normal fertilization treatment（designated as NP） just after fertilization, whereas only N_2O and NH_3 pulse emissions were evident from the nitrification inhibitor treatment（designated as ND）. The reduction proportions of N_2O and NO emissions from the ND treatment compared to those from the NP treatment during the whole maize growing period were 31% and 100%, respectively. A measurable increase of NH_3 emission from the ND treatment was found with a cumulative NH_3 emission of 3.8 ± 1.2 kg N/ha,which was 1.4 times greater than that from the NP treatment（2.7 ± 0.7 kg N/ha）.

关键词： Dicyandiamide Nitrous oxide Nitric oxide Ammonia North China Plain

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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 *** 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 *** 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 *** 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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Oxidative capacities of size-segregated haze particles in a residential area of Beijing

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Journal of Environmental Sciences 2014年第1期26卷 167-174页

作者： Zhenquan Sun Longyi Shao yujing mu Ying Hu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing Centre for Physical and Chemical Analysis State Key Laboratory of Coal Resources and Safe Mining & College of Geoscience and Surveying Engineering China University of Mining and Technology

The frequent haze days around the Chinese capital of Beijing in recent years have aroused great attention owing to the detrimental effects on visibility and public health. To discover the potential health effects of the haze, oxidative capacities of airborne particles collected in Beijing during haze and clear days were comparably assessed by a plasmid scission assay. Eleven water-soluble trace elements （As, Cd, Cr, Cu, Mn, Ni, Pb, V, Se, T1, and Zn） in the size-segregated airborne particles were quantitatively analyzed by inductively coupled plasma mass spectrometry, and most of the water- soluble trace elements were found to mainly concentrate in the fine particle size of 0.56-1.0 μm. In comparison with clear days, the mass concentrations of 11 analyzed water-soluble trace elements remarkably increased during haze days, and the oxidative capacities determined by the plasmid scission assay were markedly elevated accordingly during the haze days under the same dosage of particles as for those during clear days. Water-soluble trace elements in airborne particles, such as Cu, V, and particularly Zn, were found to have significantly positive correlations with the plasmid DNA damage rates. Because Cu, V, and Zn have been considered as bioavailable elements, the evident increase of these elements during haze days may be greatly harmful to human health.

关键词： haze water soluble trace elements plasmid scission damage size distribution

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Ambient levels of atmospheric carbonyls in Beijing during the 2008 Olympic Games

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Journal of Environmental Sciences 2010年第9期22卷 1348-1356页

作者： Zhu Xu Junfeng Liu Yujie Zhang Peng Liang yujing mu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

The measurements of atmospheric carbonyls concentrations in Beijing were conducted from 12 July to 8 October, 2008, covering the periods of the 2008 Olympic Games and Paralympic Games. Six carbonyls, including formaldehyde, acetaldehyde, acetone, butyraldehyde, valeraldehyde, and hexaldehyde, were identified in all air samples. The total average concentrations of these carbonyls before, during, and after traffic restriction were （48.1 ± 15.2）, （36.6 ± 14.5） and （23.4± 12.3） μg/m^3, respectively. Compared with the period after traffic restriction, the distinct high concentrations of the carbonyls before and during traffic restriction were primarily ascribed to the remarkable contribution of photochemical reactions. With respect to our previous investigation in the summer of 2005, the reductions of formaldehyde, acetaldehyde and acetone during traffic restriction period were about 64%, 47% and 27%, respectively, indicating that the air cleaning actions adopted by the Chinese government for the two games were efficient. The lowest levels of atmospheric carbonyls and the extremely high composition proportion of acetone after the traffic restriction were mainly attributed to the long-term effect of the control measures for the two games.

关键词： Olympic Games Paralympic Games carbonyl compounds traffic restriction photochemical reactions vehicular exhaust

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Seasonal,diurnal and nocturnal variations of carbonyl compounds in the semi-urban environment of Orléans,France

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Journal of Environmental Sciences 2016年第2期28卷 84-91页

作者： Zhaohui Jiang Benoit Grosselin Véronique Daele Abdelwahid Mellouki yujing mu Institut de Combustion Aerothermique Reactivite Environnement (ICARE) CNRS/OSUC 1C Avenue de la Recherche Scientijique 45071 Orleans Cedex 02 France College of Chemical and Biological Engineering Changsha University of Science and Technology Changsha 410004 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Atmospheric carbonyls were measured at a semi-urban site in Orléans, France, from October 2010to July2011. Formaldehyde, acetaldehyde and acetone were found to be the most abundant carbonyls, with average concentrations of 3.1, 1.0, 2.0 ppb, respectively in summer, 2.3, 0.7, 2.2 ppb, respectively in autumn, 2.2, 1.0, 2.1 ppb, respectively in spring,and 1.5, 0.7, 1.1 ppb, respectively in winter. Photo-oxidation of volatile organic compounds（VOCs） was found to make a remarkable contribution to atmospheric carbonyls in the semi-urban site based on the distinct seasonal and diurnal variations of the carbonyls, as well as the significantly positive correlations between the carbonyls and ozone. The significantly negative correlations between NO x and O_3 as well as the carbonyls and the positive correlations between wind speed and O_3 as well as the carbonyls implied that the carbonyls and O_3 at the semi-urban site were probably formed during air mass transport from neighboring cities.

关键词： Carbonyls Measurements Semi-urban

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Photochemical production of carbonyl sulfide,carbon disulfide and dimethyl sulfide in a lake water

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Journal of Environmental Sciences 2017年第1期29卷 146-156页

作者： Qianqian Du yujing mu Chenglong Zhang Junfeng Liu Yuanyuan Zhang Chengtang Liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Photochemical production of carbonyl sulfide（COS）,carbon disulfide（CS_2） and dimethyl sulfide（DMS） was intensively studied in the water from the Aohai Lake of Beijing *** lake water was found to be highly supersaturated with COS,CS_2 and DMS,with their initial concentrations of 0.91 ± 0.073 nmol/L,0.55 ± 0.071 nmol/L and 0.37 ± 0.062 nmol/L,*** evident photochemical production of COS and CS_2 in the lake water under irradiation of 365 nm and 302 nm indicated that photochemical production of them might be the reason for their *** similar dependence of wavelength and oxygen for photochemical production of COS,CS_2 and DMS implied that they might be from the same *** water cage effect was found to favor COS production but inhibit CS_2and DMS formation,indicating that COS photochemical production was mainly from direct degradation of the precursors and the formation of CS_2 and DMS needed intermediates via combination of carbon-centered radicals and sulfur-centered *** above assumptions were further confirmed by simulation experiments with addition of carbonyls and amino acids（cysteine and methionine）,and the photochemical formation mechanisms for COS,CS_2 and DMS in water were derived from the investigations.

关键词： Photochemical production Carbonyl sulfide Carbon disulfide Dimethyl sulfide Water

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Characteristics and anthropogenic sources of carbonyl sulfide in Beijing

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Journal of Environmental Sciences 2015年第2期27卷 163-170页

作者： Ye Cheng Chenglong Zhang Yuanyuan Zhang Hongxing Zhang Xu Sun yujing mu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Atmospheric mixing ratios of carbonyl sulfide（COS） in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations（R2〉 0.66） were found between COS and CO during the periods from May to June and from October to March, with slopes（ΔCOS/ΔCO） of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios.

关键词： Carbonyl sulfide Anthropogenic sources Vehicle tire wire Coal combustion Carbon monoxide

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