Comprehensive evaluation method of urban air quality statistics based on environmental monitoring data and its application.

Air quality monitoring is effective for timely understanding of the current air quality status of a region or city. Currently, the huge volume of environmental monitoring data, which has reasonable real-time performance, provides strong support for in-depth analysis of air pollution characteristics and causes. However, in the era of big data, to meet current demands for fine management of the atmospheric environment, it is important to explore the characteristics and causes of air pollution from multiple aspects for comprehensive and scientific evaluation of air quality.

[Chemical Characteristics of Arsenic in PM in Beijing].

This study assesses the chemical characteristics of As in aerosol PM samples that were collected from July 2011 to May 2012 in Beijing, China. Total As, As(Ⅲ), and As(Ⅴ) were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), high performance liquid chromatography (HPLC), and hydride generation atomic fluorescence (HG-AFS), respectively. The average concentrations of total As, As(Ⅲ) and As(Ⅴ) over the entire sampling period were (21.

[Emission Characteristics of Chemical Composition of Particulate Matter from Coal-fired Boilers].

Samples of particulate matter from coal-fired boilers of different tons were collected in Lanzhou city, and the water-soluble inorganic ions, carbonaceous species, water-soluble organic compounds (WSOC) and polycyclic aromatic hydrocarbons (PAHs) were analyzed. The results showed that SO, Cl, and Ca were the most important water-soluble ions in the coal-fired boiler samples, accounting for 35.13%, 23.

Impact of emissions controls on ambient carbonyls during the Asia-Pacific Economic Cooperation summit in Beijing, China.

Beijing and its surrounding areas implemented a series of stringent measures to ensure good air quality during the Asia-Pacific Economic Cooperation (APEC) summit. These measures included restrictions on traffic, constructions, and industrial activities. The diurnal variations of carbonyls, 24-h PM, and its chemical species were investigated before, during, after APEC, and the 2015 summer.

[Chemical Characteristics and Sources of Heavy Metals in Fine Particles in Beijing in 2011-2012].

In order to investigate the chemical characteristics and sources of atmospheric heavy metals, PM samples were collected every three days during the summer of 2011 and summer of 2012. The samples were analyzed for Li, V, Cr, Mn, Co, Cu, Zn, As, Se, Ti, Ga, Ni, Sr, Cd, In, Ba, Tl, Pb, Bi, and U by ICP-MS, with an emphasis on seven major heavy metal elements (Zn, Pb, Mn, Cu, As, V, and Cr). The concentrations of Zn, Pb, Mn, Cu, As, V, and Cr were (331.

Chemical characteristics and source apportionment of PM in Lanzhou, China.

Daily PM samples were collected during winter 2012 and summer 2013 at an urban site in Lanzhou and were analyzed for chemical compounds including water soluble inorganic ions (WSIN), trace elements, water soluble organic carbon (WSOC), carbonaceous species (OC/EC), polycyclic aromatic hydrocarbons (PAHs), and humic-like substances (HULIS). The seasonal-average reconstructed PM mass was 120.5μgm in winter and 34.

Ambient volatile organic compounds pollution in China.

Owing to rapid economic and industrial development, China has been suffering from degraded air quality and visibility. Volatile organic compounds (VOCs) are important precursors to the formation of ground-level ozone and hence photochemical smog. Some VOCs adversely affect human health.

[Spatial Distribution Characteristics of NMHCs in Spring in Cangzhou City].

Simultaneous collections of non-methane hydrocarbons (NMHCs) were carried out at 15 sampling sites including urban, suburb and potential pollution areas in Cangzhou City in spring 2015. The results showed that NMHCs were generally higher in urban areas than those in suburb and rural areas; the highest concentration of NMHCs was observed at Cangzhou High-tech zone (urban area); the concentrations of NMHCs were significantly lower at rural sites than in most urban sites except Hejian site; vehicular emissions were the main sources of NMHCs in Cangzhou; Cangzhou chemical fertilizer plant and Cangzhou oil refinery had no significant influence on urban NMHCs during their shutdown period; Dagang Oilfield, with better oil and gas recovery systems, did not have a significant impact on urban NMHCs. In general, alkanes, alkenes and aromatics accounted for 65%, 16% and 19% of NMHCs in Cangzhou City, respectively; xylene (19%), ethylene (14%), toluene(11%), propylene (5%), isopentane (5%) and isopentene (5%) were the most dominant contributors to ozone formation potential; aerosol formation potential was mainly derived from toluene (28%), pinene (28%), xylene(16%), ethylbenzene (9%) and benzene (9%).

[Pollution Characteristics of Non-methane Hydrocarbons During Winter and Summer in Foshan City].

Thirty non-methane hydrocarbons(NMHCs) samples were collected and analyzed in Foshan City during winter 2014 and summer 2015. The concentrations of NMHCs during the sampling period were 122.30 μg·m and 56.

Chemical characterization of humic-like substances (HULIS) in PM in Lanzhou, China.

Evaporative light scattering detection (ELSD) was applied to quantify HULIS (humic-like substances) for the first time in 2012 winter and 2013 summer at an urban site in Lanzhou. Water soluble organic carbon (WSOC), water soluble inorganic ions, and carbonaceous species (OC/EC) were also analyzed. The results show that OM (Organic Matter=OC×1.

[Pollution Characteristics and Source of HULIS in the Fine Particle During the Beijing APEC].

In order to investigate the influence of the emission reduction measure during the Beijing APEC on the concentrations and pollution characteristics of humic-like substances (HULIS) in atmospheric fine particles, PM₂.₅ samples were collected and analyzed for OCEC, WSOC, HULIS and water-soluble ions. The concentration of HULIS in PM₂.

[Pollutional Characteristics and Sources Analysis of Polycyclic Aromatic Hydrocarbons in Atmospheric Fine Particulate Matter in Lanzhou City].

Polycyclic aromatic hydrocarbons (PAHs) are a group of important toxic compounds. In order to detect the pollutional characteristics of atmospheric PAHs in Fine Particulate Matter (PM), a total of 60 PM samples were collected in Lanzhou City during the winter of 2012 and summer of 2013. The GC/MS measurement results of the samples demonstrated the averagely total mass concentrations of the most significant 16 homologues of PAHs were (191.

Long-term trends of chemical characteristics and sources of fine particle in Foshan City, Pearl River Delta: 2008-2014.

Foshan is a major international ceramic center and the most polluted city in the Pearl River Delta (PRD). Here we present the results of the first long-term PM2.5 (particles <2.

Source of atmospheric heavy metals in winter in Foshan, China.

Foshan is a ceramics manufacturing center in the world and the most polluted city in the Pearl River Delta (PRD) in southern China measured by the levels of atmospheric heavy metals. PM2.5 samples were collected in Foshan in winter 2008.

[Seasonal variation of carcinogenic heavy metals in PM2.5 and source analysis in Beijing].

During April, July, October 2009 and January 2010, daily (24-h average) PM2.5 samples were collected at urban sites in Beijing and 29 metal elements were analyzed by the ICP-MS. The characteristics of 7 carcinogenic heavy metal mass concentrations, enrichment, and possible sources were discussed.

Size distribution, characteristics and sources of heavy metals in haze episode in Beijing.

Size segragated samples were collected during high polluted winter haze days in 2006 in Beijing, China. Twenty nine elements and 9 water soluble ions were determined. Heavy metals of Zn, Pb, Mn, Cu, As, Cr, Ni, V and Cd were deeply studied considering their toxic effect on human being.

[Spatial distribution characteristics of NMHCs during winter haze in Beijing].

NMHCs and NOx samples were simultaneously collected and analyzed in six urban and suburban representative sampling sites (Sihuan, Tian'anmen, Pinguoyuan, Fatou, Beijing Airport and Miyun) during a typical haze period in winter 2005, Beijing. The concentrations of NMHCs during the sampling period in descending order were: Sihuan (1101.29 microg x m(-3)) > Fatou (692.

[Pollution characteristics of organic acids in atmospheric particles during haze periods in autumn in Guangzhou].

Total suspended particles (TSP), collected during a typical haze period in Guangzhou, were analyzed for the fatty acids (C12-C30) and low molecular weight dicarboxylic acids (C3-C9) using gas chromatography/mass spectrometry (GC/MS). The results showed that the concentration of total fatty and carboxylic acids was pretty high during the haze episode. The ratios of fatty acids and carboxylic acids in haze to those in normal days were 1.

Size distributions and sources of elements in particulate matter at curbside, urban and rural sites in Beijing.

Size distributions of 29 elements in aerosols collected at urban, rural and curbside sites in Beijing were studied. High levels of Mn, Ni, As, Cd and Pb indicate the pollution of toxic heavy metals cannot be neglected in Beijing. Principal component analysis (PCA) indicates 4 sources of combustion emission, crust related sources, traffic related sources and volatile species from coal combustion.

Nonmethane Hydrocarbons in Ambient Air of Hazy and Normal Days in Foshan, South China.

A first study of nonmethane hydrocarbons (NMHCs) on hazy and normal days was performed in Foshan for providing deep insight into the local deteriorating air quality. Ethane, propane, i-pentane, ethene, propene, ethyne, benzene, and toluene were eight most abundant compounds, accounting for 71%-85% of total NMHCs. Most hydrocarbons showed much higher levels on hazy days than normal days together with hydrocarbon/ethyne ratios and diurnal variations, indicating hazy days are more dominated by vehicular emission.

Characteristics of atmospheric non-methane hydrocarbons during haze episode in Beijing, China.

This study firstly focused on non-methane hydrocarbons (NMHCs) during three successive days with haze episode (16-18 August 2006) in Beijing. Concentrations of alkanes, alkenes, aromatic hydrocarbons, and ethyne all peaked at traffic rush hour, implying vehicular emission; and alkanes also peaked at non-traffic rush hour in the daytime, implying additional source. Especially, alkanes and aromatics clearly showed higher levels in the nighttime than that in the daytime, implying their active photochemical reactions in the daytime.

Harmonizing aerosol carbon measurements between two conventional thermal/optical analysis methods.

Although total carbon (TC) can be consistently quantified by various aerosol carbon measurement methods, the demarcation of TC into organic carbon (OC) and elemental carbon (EC) has long been inconsistent. The NIOSH and IMPROVE protocols are most widely used for thermal/optical analysis (TOA), but current knowledge rests in the description that the NIOSH protocol usually gives lower EC values than does the IMPROVE protocol. This study seeks to explore the possibility of quantitatively linking the difference between the two TOA protocols.

Chemical characteristics of PM2.5 during a typical haze episode in Guangzhou.

The chemical characteristics (water-soluble ions and carbonaceous species) of PM2.5 in Guangzhou were measured during a typical haze episode. Most of the chemical species in PM2.