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121.
Physical characterization and chemical analysis of settled dusts collected in Xi’an from November 2007 to December 2008 show that (1) dust deposition rates ranged from 14.6 to 350.4 g m−2 yr−1. The average deposition rate (76.7 g m−2 yr−1) ranks the 11th out of 56 dust deposition rates observed throughout the world. The coal-burning power was the major particle source; (2) on average (except site 4), ∼10% of the settled dusts having size <2.6, ∼30% having size <10.5, and >70% having size <30 μm; (3) the concentrations for 20 out of 27 elements analyzed were upto 18 times higher than their soil background values in China. With such high deposition rates of dusts that contain elevated levels of toxic elements, actions should be taken to reduce emission and studies are needed to assess the potential impacts of settled particles on surface ecosystem, water resource, and human health in the area. 相似文献
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通过超声波-铁粉联合体系协同降解废水中的五氯酚(PCP).实验结果表明:降解120 min后,PCP去除率可达90.4%;在该体系中铁粉被逐渐腐蚀成Fe2+,随降解时间的延长,Fe2+浓度逐渐增加;体系中的Fe2+可以促进·OH的产生,并且可以与超声空化作用下产生的H2O2发生Fenton试剂氧化反应降解PCP;超声波... 相似文献
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Fu Li Chen Yi Yang Xinyi Yang Zuyao Liu Sha Pei Lei Feng Baixiang Cao Ganxiang Liu Xin Lin Hualiang Li Xing Ye Yufeng Zhang Bo Sun Jiufeng Xu Xiaojun Liu Tao Ma Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air... 相似文献
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Rachnarin Nitisoravut Cao N. D. Thanh Roshan Regmi 《International Journal of Green Energy》2017,14(8):712-723
There is an increasing trend to conduct the researches related to Microbial Fuel Cells (MFCs) in the recent years. Limited power output has been the major obstacle for the practical application and upscaling of MFCs. Attempts have been made on electrode modifications such as anode treatments, cathode modifications with catalysts and bio cathodes developments to produce varying degrees of improved output current depending upon the types of modifications. Power density and Coulombic efficiency have been considered as the important parameters to analyze the system performances. This paper overviews on the advances made in MFCs’ researches focusing on different types of electrodes modifications along with the involved methodology. Furthermore, the system performances of different modified MFCs are compared in terms of the power density and the Coulombic efficiency. 相似文献
129.
The solar radiation data are of high importance to the solar energy systems. Conventional methods to obtain the solar radiation data are from weather stations, solar radiation models, commercial software databases, and field measurements. In the present study, a new daily global solar radiation model is proposed, by combining the quadratic function of sunshine fraction and sine function of the day of the year. The solar radiation model calculated data are then compared with China Meteorological Data Sharing System (CMDSS) data, TRNSYS data, and field-measured data in Northwest China climate. It is found that the newly proposed solar radiation model has better performance than the other nine solar radiation models in the literature. The solar radiation model calculated data fit well with the CMDSS annually average data. The TRNSYS data are a bit larger than the CMDSS annually average data in summer half year and a little smaller than those in winter half year. The solar radiation model and the CMDSS annually average data have the best correlation, whereas the TRNSYS data and the field-measured data have the worst correlation. The solar radiation model calculated data have the best correlation with the other three data sources. 相似文献
130.
Ionic composition of TSP and PM2.5 during dust storms and air pollution episodes at Xi'an,China 总被引:1,自引:0,他引:1
Zhenxing Shen Junji Cao Richard Arimoto Zhiwei Han Renjian Zhang Yuemei Han Suixin Liu Tomoaki Okuda Shunsuke Nakao Shigeru Tanaka 《Atmospheric environment (Oxford, England : 1994)》2009,43(18):2911-2918
TSP and PM2.5 samples were collected at Xi'an, China during dust storms (DSs) and several types of pollution events, including haze, biomass burning, and firework displays. Aerosol mass concentrations were up to 2 times higher during the particulate matter (PM) events than on normal days (NDs), and all types of PM led to decreased visibility. Water-soluble ions (Na+, NH4+, K+, Mg2+, Ca2+, F?, Cl?, NO3?, and SO42?). were major aerosol components during the pollution episodes, but their concentrations were lower during DSs. NH4+, K+, F?, Cl?, NO3?, and SO42? were more abundant in PM2.5 than TSP but the opposite was true for Mg2+ and Ca2+. PM collected on hazy days was enriched with secondary species (NH4+, NO3?, and SO42) while PM from straw combustion showed high K+ and Cl?. Firework displays caused increases in K+ and also enrichments of NO3? relative to SO42?. During DSs, the concentrations of secondary aerosol components were low, but Ca2+ was abundant. Ion balance calculations indicate that PM from haze and straw combustion was acidic while the DSs samples were alkaline and the fireworks' PM was close to neutral. Ion ratios (SO42?/K+, NO3?/SO42?, and Cl?/K+) proved effective as indicators for different pollution episodes. 相似文献