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351.
基于三次指数平滑模型的雾霾天气分析与预测 总被引:1,自引:0,他引:1
通过建立三次指数平滑模型,分析2002~2012年我国二氧化硫和烟尘的排放量以及每年在环境污染治理方面的投资总额等指标,得出未来3年内我国雾霾天气仍会频发的结论,并究其原因进行了分析。 相似文献
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A. Murad X. D. Zhou P. Yi D. Alshamsi A. Aldahan X. L. Hou Z. B. Yu 《Environmental monitoring and assessment》2014,186(10):6157-6167
Groundwater is the most valuable resource in arid regions, and recognizing radiological criteria among other water quality parameters is essential for sustainable use. In the investigation presented here, gross-α and gross-β were measured in groundwater samples collected in the south-eastern Arabian Peninsula, 67 wells in Unite Arab Emirates (UAE), as well as two wells and one spring in Oman. The results show a wide gross-α and gross-β activities range in the groundwater samples that vary at 0.01~19.5 Bq/l and 0.13~6.6 Bq/l, respectively. The data show gross-β and gross-α values below the WHO permissible limits for drinking water in the majority of the investigated samples except those in region 4 (Jabel Hafit and surroundings). No correlation between groundwater pH and the gross-α and gross-β, while high temperatures probably enhance leaching of radionuclides from the aquifer body and thereby increase the radioactivity in the groundwater. This conclusion is also supported by the positive correlation between radioactivity and amount of total dissolved solid. Particular water purification technology and environmental impact assessments are essential for sustainable and secure use of the groundwater in regions that show radioactivity values far above the WHO permissible limit for drinking water. 相似文献
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In this paper the mechanism and kinetic of ozone decomposition under the irradiation of 253.7 nm UV-light were studied.The quantum yield of the ozone depletion in the presence of methyl bromide is further determined and a reaction model is provided to explain the experimental fact. 相似文献
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大学语文教学是传播文化观念、提高大学生人文素质的主渠道,本文从大学语文教学的内容、模式、原则以及方法等不同角度来探讨如何加强大学语文教学效果,如何在提高大学生母语运用能力的同时,培养其高尚的道德情操和健康的审美情趣. 相似文献
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Ozone decomposition under the irradiation of 253.7 nm in the presence of methyl bromide 总被引:2,自引:0,他引:2
IntroductionOverpastten years,thestratosphericozonedepletionhasbeencontributedtotheactivechlorideandbromide(Harris,1995) .Althoughtheconcentrationofbromideismuchlessthanthatofchloride,theozonedepletionefficiencyofbromideis 50timesgreater (Harris,1995;McElroy ,1986)… 相似文献
360.
Xin Jin Weijie Zhang Rui Hou Pengkang Jin Jina Song Xiaochang C. Wang 《环境科学学报(英文版)》2019,31(2):289-298
The characteristics of effluent organic matter (EfOM) from a wastewater treatment plant (WWTP) during ozonation were investigated using excitation and emission matrix (EEM) spectra, Fourier transform infrared spectroscopy (FT-IR) and high-performance size exclusion chromatography (HPSEC) at different ozone dosages. The selectivity of ozonation towards different constituents and functional groups was analysed using two-dimensional correlation spectra (2D-COS) probed by FT-IR, synchronous fluorescence spectra and HPSEC. The results indicated that ozonation can destroy aromatic structures of EfOM and change its molecular weight distribution (MWD). According to 2D-COS analysis, microbial humic-like substances were preferentially removed, and then the protein-like fractions. Terrestrial humic-like components exhibited inactivity towards ozonation compared with the above two fractions. Protein-like substances with small molecular weight were preferentially reacted during ozonation based on 2D-COS probed by HPSEC. In addition, the selectivity of ozone towards different functional groups of EfOM exhibited the following sequence: phenolic and alcoholic CO groups?>?aromatic structures containing CC double bonds?>?aliphatic CH. X-ray photoelectron spectroscopy (XPS) further elucidated the preferential reaction of aromatic structures in EfOM during ozonation. 相似文献