Publications by authors named "Kai-shan Zhang"

Regional meteorological conditions and emissions reduction are closely related to air quality. China has a monsoonal climate and regional meteorological conditions are significantly impacted by interannual climate variability. The objective of this study was to evaluate the contributions of meteorological conditions and emissions reduction to regional improvements in air quality.

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As important components of PM, metal elements are extremely harmful to people and also have source specificity. Understanding the characteristics of PM metal pollution in the two different types of cities can help adjust the layout of regional industrial structure and improve the environment. PM samples during haze/non-haze periods were collected in Chengdu City and Renshou County.

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To compare the pollution characteristics of carbonaceous aerosol components in the atmosphere between urban and suburban areas, Chengdu City and Renshou County were selected as study areas from which 88 samples of PM during haze and non-haze periods were collected and analyzed. Quantification of mass concentrations of PM, carbonaceous aerosol components[organic carbon (OC), elemental carbon (EC), and secondary organic carbon (SOC)], along with correlation analysis of OC and EC, and principal component analysis (PCA) of carbon components were carried out. The results show that pollutant concentrations during the haze period were higher than those during the non-haze period.

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Emissions from non-road equipment are attracting more attention due to their increasing contribution to air pollution. Thus, an accurate estimate of emission inventory for non-road equipment is imperative for air quality management and improvement. Activity data from a large range of construction equipment were collected from multiple sources, including on-site/phone interviews and literature review, and used for further analysis to characterize its operations.

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In this paper, the objective is to characterize real-world tailpipe emissions for excavators. Eight excavators in several construction sites in Chengdu were selected in this study. A portable emission measurement system (PEMS) was used for real-world emissions measurements (i.

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With culture-independent approach, microbial total DNA was directly extracted from Pachychalina sp. Using the total microbial DNA as template, archaeal 16S rDNAs were amplified by PCR with universal primers. Amplified products were cloned into T-vector and secondarily amplified by PCR.

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