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Study on the Current Situation and Source apportionment of PM_(2.5) Pollution in China

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Asian Agricultural Research 2015年第1期7卷 66-70页

作者： Nianliang CHENG Shangyin GAO Yunting LI Bingfen CHENG Kuikui YUAN Beijing Municipal Environmental Monitoring Center Tsinghua Holdings Human Settlements Environment Institute Shanxi Academy for Environmental Planning

In this paper,using concentration data of PM2. 5in 2013 in China and referring to a lot of literature,we preliminary studied the pollution of fine particulate matter and summarized PM2. 5source apportionment in the key cities in China. Our results showed that PM2. 5showed significant spatial and temporal distribution; high surface concentrations of PM2. 5concentrated mainly in the North China Plain,the Sichuan Basin,Yangtze River Delta and other regions; the average annual concentration of PM2. 5was about 80μg / m3 in North China Plain; Seasonal changes in the concentration of PM2. 5was winter > spring > autumn > summer; fired sources,industrial sources,vehicle exhaust were the major sources of PM2. 5; motor vehicle exhaust mostly contributed 10%- 30% to PM2. 5. This review provides a fundamental understanding of PM2. 5source apportionment and serves as an important reference for future source apportionment studies to be widely conducted in China.

关键词： China PM2.5 Source apportionment Pollution charact

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养廉银无以养廉

Source apportionment of Air Particulates in South Africa: A Review

明清史 2021年第2期

作者：刘凤云

雍正朝耗羡归公及养廉银制度的建立，是国家体制内一次“正其制度”的结构性改革，然其成效是短暂的。改革并没有改变低税收的国家财政，地方经费不足的问题无法从根本上解决。养廉银制度中公私界限的模糊，使制度自建立伊始便充当着“... 详细信息

雍正朝耗羡归公及养廉银制度的建立，是国家体制内一次“正其制度”的结构性改革，然其成效是短暂的。改革并没有改变低税收的国家财政，地方经费不足的问题无法从根本上解决。养廉银制度中公私界限的模糊，使制度自建立伊始便充当着“地方财政的储备银两”的角色。从乾隆朝摊捐养廉银之风兴起，到嘉庆初公私三七分割，再到以情急为借口的肆意摊捐，已掏空自督抚到州县各级官员的腰包。而由摊捐养廉银带来的官员低俸甚或无俸的政治风险，又导致官场腐败的加剧和国家钱粮的不断流失。嘉道年间各类名目的加赋、陋规重现于各省，然嘉、道两朝都已无法再复制耗羡归公的财政改革，养廉银无以养廉，是官僚体制内部改革无法解决的难题。

关键词：清代养廉银摊捐耗羡归公财政改革　　Qing Dynasty Nourishing Honesty Silver apportionment Haoxianguigong(耗羡归公) Fiscal Reform

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Atmospheric and Climate Sciences 2019年第1期9卷 100-113页

作者： Manny Mathuthu Violet Patricia Dudu Munyaradzi Manjoro Centre for Applied Radiation Science and Technology (CARST) North-West University Mafikeng Campus Mafikeng South Africa Department of Environmental Science Bindura University of Science Education Bindura Zimbabwe Department of Geography and Environmental Science North-West University Mafikeng Campus Mafikeng South Africa

Source apportionment studies are useful in understanding sources of pollution and can be used in health risk assessments to evaluate the human health impacts from air pollutants. This study reviewed and analysed available source apportionment studies of air particulate in South Africa in October 2016. Searches were performed using different databases for peer reviewed articles including Google scholar, Scopus, EbscoHost, Science Direct and National Research Foundation database. Source categories were identified and these varied depending on the sites where the research was conducted (rural, urban or remote) but biomass burning dominated. A total of 35 source apportionment records were found with the majority of studies in urban areas (60%) while industrial sites had the least number of records (17.1%). The period 2011-2016 had the highest number of records while 1990-1995 had only three publicly available studies. There is limited research on source apportionment studies of air particulate in South Africa, calling for more research in this area.

关键词： Air Particulate Source apportionment Air Pollution South Africa Source Categories

Sources of methacrolein and methyl vinyl ketone and their contributions to methylglyoxal and formaldehyde at a receptor site in Pearl River Delta

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Journal of Environmental Sciences 2019年第5期31卷 1-10页

作者： Zhenhao Ling Zhuoran He Zhe Wang Min Shao Xuemei Wang School of Atmospheric Sciences Sun Yat-sen University Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University Department of Civil and Environmental Engineering Hong Kong Polytechnic University Institute for Environmental and Climate Research Jinan University

Methacrolein(MACR) and methyl vinyl ketone(MVK) are two major intermediate products from the photochemical oxidation of isoprene, the most important biogenic volatile organic compound. In addition, MACR and MVK have primary emissions. Investigating the sources and evolution of MACR and MVK could provide helpful information for the oxidative capacity of the atmosphere. In this study, hourly measurements of isoprene, MACR, and MVK were conducted at a receptor site in the Pearl River Delta region(PRD), i.e., the Heshan site(HS), from 22 October to 20 November, 2014. The average mixing ratios of isoprene,MACR and MVK were 151 ± 17, 91 ± 6 and 79 ± 6 pptv, respectively. The daily variations and the ratios of MVK/MACR during daytime and nighttime suggested that other sources besides isoprene photooxidation influenced the MACR and MVK abundances at the HS.Positive matrix factorization was utilized to resolve the sources of MACR and MVK. Five sources were identified and quantified, including biogenic emissions, biomass burning,secondary formation, diesel, and gasoline vehicular emissions. Among them, secondary formation made the greatest contribution to observed MACR and MVK with average contributions of ～ 45% and ～ 70%, respectively. Through the yields of secondary products from the oxidation of MACR and MVK by the OH radical and the concentrations of MACR and MVK, it was found that methylglyoxal and formaldehyde were the main oxidation products of MACR and MVK at the HS site. Overall, this study evaluated the roles of primary emissions on ambient levels of MACR and MVK and advanced the understanding of photochemical oxidation of MACR and MVK in the PRD.

关键词： Source apportionment Methacrolein Methyl vinyl ketone Pearl River Delta

Assessment of sources and transformation of nitrate in the alluvial-pluvial fan region of north China using a multi-isotope approach

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Journal of Environmental Sciences 2020年第3期32卷 9-22页

作者： Qianqian Zhang Huiwei Wang Hebei and China Geological Survey Key Laboratory of Groundwater Remediation Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesShijiazhuang 050061China

A multi-isotope approach and mixing model were combined to identify spatial and seasonal variations of sources,and their proportional contribution to nitrate in the Hutuo River alluvial-pluvial fan region.The results showed that the NO3- concentration was significantly higher in the Hutuo River valley plain(178.7 mg/L) region than that in the upper and central pluvial fans of the Hutuo River(82.1 mg/L and 71.0 mg/L,respectively)and in the river(17.0 mg/L).Different land use types had no significant effect on the groundwater nitrate concentration.Based on a multi-isotope approach,we confirmed that the main sources of groundwater nitrate in different land use areas were domestic sewage and manure,followed by soil nitrogen,ammonia fertilizer,nitrate fertilizer and rainwater,and there were no significant spatial or seasonal variations.Combining δ^15N-NO3,δ^18O-NO3- and δ^37Cl results can increase the accuracy of traceability.Nitrification could be the most important nitrogen migration and transformation process,and denitrification did not significantly affected the isotopic composition of the nitrate.The SIAR model outputs revealed that the main nitrate pollution sources in groundwater and river water were domestic sewage and manure,accounting for 55.9%-61.0% and 22.6%(dry season),50.3%-60.4% and 34.1%(transition season),42.7%-47.6% and 35.6%(wet season 2016) and 45.9%-46.7% and 38.4%(wet season 2017),respectively.This work suggests that the random discharge and disposal of domestic sewage and manure should be the first target for control in order to prevent further nitrate contamination of the water environment.

关键词： Nitrate Source apportionment Multi-isotope SIAR mixing model

Source apportionment of PM2.5 in the Metropolitan Area of Costa Rica Using Receptor Models

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Atmospheric and Climate Sciences 2013年第4期3卷 562-575页

作者： Jorge Herrera Murillo Susana Rodríguez Roman José Félix Rojas Marín Beatriz Cardenas DGCENICA Instituto Nacional de Ecología México DF México Escuela de Química Universidad de Costa Rica Ciudad Universitaria Rodrigo Facio Costa Rica Laboratorio de Análisis Ambiental Escuela Ciencias Ambientales Universidad Nacional Heredia Costa Rica

In this work, receptor models were used to identify the PM2.5 sources and its contribution to the air quality in residential, comercial and industrial sampling sites in the Metropolitan Area of Costa Rica. Principal component analysis with absolute principal component scores (PCA-APCS), UNIMX and positive matrix factorization (PMF) was applied to analyze the data collected during 1 year of sampling campaign (2010-2011). The PM2.5 samples were characterized through its composition looking for trace elements, inorganic ions and organic and elemental carbon. These three models identified some common sources of PM2.5: marine aerosol, crustal material, traffic, secondary aerosols (secondary sulfate and secondary nitrate resolved by PMF), a mixed source of heavy fuels combustion and biomass burning, and industrial emissions. The three models predicted that the major sources of PM2.5 in the Metropolitan Area of Costa Rica were related to anthropogenic sources (73%, 65% and 69%, respectively, for PCA-APCS, Unmix and PMF) although natural sources also contributed to PM2.5 (21%, 24% and 26%). On average, PCA and PMF methods resolved 94% and 95% of the PM2.5 mass concentrations, respectively. The results were comparable to the estimate using UNMIX.

关键词： PM2.5 Chemical Composition Costa Rica Source apportionment Receptor Models

The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China

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Journal of Environmental Sciences 2019年第5期31卷 121-134页

作者： Zhuobiao Ma Chengtang Liu Chenglong Zhang Pengfei Liu Can Ye Chaoyang Xue Di Zhao Jichen Sun Yiming Du Fahe Chai Yujing Mu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Shenyang Academy of Environmental Sciences Shenyang Environmental Monitoring Centre Chinese Research Academy of Environmental Sciences

Air concentrations of volatile organic compounds(VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most(36.15%) to the total propene-equivalent concentration of the measured VOCs,followed by combustion emission(16.92%), vegetation emission and secondary formation(14.33%), solvent usage(10.59%), petrochemical industry emission(9.89%), petrol evaporation(6.28%), and liquefied petroleum gas(LPG) usage(5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O_3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics,e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O_3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O_3 pollution in Shenyang.

关键词： Volatile organic compounds Source apportionment Photochemical ozone formation Field measurement

Effect of air masses motion on the rapid change of aerosols in marine atmosphere

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Journal of Environmental Sciences 2019年第9期31卷 217-228页

作者： Jinpei Yan Qi Lin Miming Zhang Shuhui Zhao Liqi Chen Third Institute of Oceanography Ministry of Natural Resources Xiamen 361005 China Key Laboratory of Global Change and Marine-Atmospheric Chemistry Xiamen 361005 China

The impact of air masses motion on marine aerosol properties was investigated using an on-board single particle mass spectrometer(SPAMS) deployed for the determination of single particle size resolved chemical composition over Southeast China Sea. Two aerosol blooms(E1 and E2) were observed during the cruise. High average particle number count occurred in E1(7320), followed by E2(5850), which was more than 100–150 times of the average particle number count during normal periods. Particles were classified as four major sources, including continental source, shipping source, marine source, and transport source based on the mass spectral similarity. Transport source was identified as those particles with high particle number count occurred only during aerosol bloom period. Three sub-types of EC-Ca, OC-Ca, and Al-rich were classified as transport source.EC-Ca was the dominant particles of the transport source, accounting for more than 70%of the total particles in aerosol bloom events. A uni-modal size distribution in the size range of 0.1–2.0 μm was observed during normal period, while a bimodal distribution with a tiny mode(<0.3 μm) and a coarse mode between 0.4 and 0.6 μm was present during aerosol bloom. The variation of aerosol source is consistent with air masses back trajectories, for the reason that most of the long-range air trajectories are from the ocean,while short air trajectories originate in the continental regions, which means that air masses have a significant impact on the aerosol physical–chemical properties along their tracks.

关键词： Marine aerosol Chemical composition Source apportionment Air masses Single particle aerosol mass spectrometer(SPAMS)

Application of Bootstrap in Dose apportionment of Nuclear Plants Via Uncertainty Modeling of the Effluent Released from Plants

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World Journal of Nuclear Science and Technology 2012年第1期2卷 41-47页

作者： Debabrata Datta Health Physics Division Bhabha Atomic Research Centre

Nuclear power plants are always operated under the guidelines stipulated by the regulatory body. These guidelines basically contain the technical specifications of the specific power plant and provide the knowledge of the discharge limit of the radioactive effluent into the environment through atmospheric and aquatic route. However, operational constraints sometimes may violate the technical specification due to which there may be a failure to satisfy the stipulated dose apportioned to that plant. In a site having multi facilities sum total of the dose apportioned to all the facilities should be constrained to 1 mSv/year to the members of the public. Dose apportionment scheme basically stipulates the limit of the gaseous and liquid effluent released into the environment. Existing methodology of dose apportionment is subjective in nature that may result the discharge limit of the effluent in atmospheric and aquatic route in an adhoc manner. Appropriate scientific basis for dose apportionment is always preferable rather than judicial basis from the point of harmonization of establishing the dose apportionment. This paper presents an attempt of establishing the discharge limit of the gaseous and liquid effluent first on the basis of the existing value of the release of the same. Existing release data for a few years (for example 10 years) for any nuclear power station have taken into consideration. Bootstrap, a resampling technique, has been adopted on the existing release data sets to generate the corresponding population distribution of the effluent release. Cumulative distribution of the population distribution obtained is constructed and using this cumulative distribution, 95th percentile (upper bound) of the discharge limit of the radioactive effluents is computed. Dose apportioned for a facility is evaluated using this estimated upper bound of the release limit. Paper de- scribes the detail of the bootstrap method in evaluating the release limit and also presents the comparative study of the dose apportionment

关键词： Dose apportionment Radioactive Effluent Cumulative Distribution Bootstrap Percentile