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Submicron aerosol is of extensive concern not only due to its significant impact on air quality but also because it is detrimental to human health. In this study, we investigated the characteristics, sources and chemical processes of submicron aerosol based on realtime online measurements of submicron aerosols(NR-PM 1) during December 2015 at an urban site in Beijing. The average mass concentration of NR-PM 1 was 92.5 ±84.9 μg/m3, the hourly maximum was 459.1 μg/m3 during t... 相似文献
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The national lockdown policies have drastically disrupted socioeconomic activities during the COVID-19 pandemic in China, which provides a unique opportunity to investigate the air quality response to such anthropogenic disruptions. And it is meaningful to evaluate the potential health impacts of air quality changes during the lockdown, especially for PM2.5 with adverse health effects. In this study, by using PM2.5 observations from 1388 monitoring stations nationwide in China, we examine the PM2.5 variations between the COVID-19 lockdown (February and March in 2020) and the same period in 2015–2019, and find that the national average of PM2.5 decreases by 18 μg/m3, and mean PM2.5 for most sites (about 75%) decrease by 30%–60%. The anthropogenic and meteorological contributions to these PM2.5 variations are also determined by using a stepwise multiple linear regression (MLR) model combined with the Kolmogorov–Zurbenko filter. Our results show that the change of anthropogenic emissions is a leading contributor to those widespread PM2.5 reductions, and meteorological conditions have the negative influence on PM2.5 reductions for some regions, such as Beijing–Tianjin–Hebei (BTH). Additionally, the avoided premature death due to PM2.5 reduction is estimated as a predicted number based on a log-linear concentration-response function. The total avoided premature death is 9952 in China, with dominant contribution (94%) from anthropogenic emission changes. For BTH, Yangtze River Delta, Pearl River Delta and Hubei regions, the reductions of PM2.5 are 24.1, 24.3, 13.5 and 29.5 μg/m3, with the avoided premature deaths of 1066, 1963, 454 and 583, respectively. 相似文献
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浅析胜利油田废弃钻井液无害化处理技术 总被引:5,自引:1,他引:5
高月臣 《安全.健康和环境》2008,8(3):29-30
通过对废弃钻井液的危害分析,结合胜利油田的现状,提出了3种无害化处理方法,建议根据实际选择性使用,来满足当前石化企业实施清洁生产的要求. 相似文献
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Li Xiaoping Cai Yue Liu Dongying Ai Yuwei Zhang Meng Gao Yu Zhang Yuchao Zhang Xu Yan Xiangyang Liu Bin Yu Hongtao Mielke Howard W. 《Environmental science and pollution research international》2019,26(6):5564-5576
Environmental Science and Pollution Research - Utilization of microbes is one of the most promising methods to remediate potentially toxic metals (PTMs) from soil. In this study, a systematic... 相似文献
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Preparation of spherical iron nanoclusters in ethanol-water solution for nitrate removal 总被引:7,自引:0,他引:7
In this study, a higher surface area spherical nanoscale zero valent iron (HNZVI) cluster (80 nm, 54.25 m(2)g(-1)) was synthesized in ethanol-water mixed solvent in the presence of dispersion agent of polyglycol (PEG). At the same time, a lower surface area nanoscale zero valent iron (LNZVI) particle (80 nm, 8.08 m(2)g(-1)) was also prepared with only de-ioned water as reaction media. Their structures, compositions and physical properties were characterized by transmission electron microscope (TEM), X-ray diffractometer (XRD), inductively coupled plasma atomic emission spectrophotometer (ICP-AES), and Brunauer-Emmett-Teller (BET) surface area analyzer and the results obtained for these two kinds of nanoscale iron were compared with each other and also with those reported in the literatures. The HNZVI clusters seemed to be accumulated by smaller iron particles (<10 nm). At the same time, whiskers were formed in the final produce. Reactivity of the HNZVI was affirmed via denitrification of nitrate. The factors controlling the reduction of nitrate, such as pH, dissolved oxygen (DO), iron content as well as the initial nitrate concentration were also discussed. Finally, kinetic analysis revealed that chemical reduction of nitrate by HNZVI could not be described by the first- or pseudo-first-order kinetic model. 相似文献
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