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671.
利用一种新的微生物学分析方法,研究了原水中微生物可利用磷(MAP)以及总磷(TP)、溶解性正磷酸盐(SRP)在净水工艺中的去除情况.结果表明,生物预处理、生物活性炭及常规的混凝沉淀砂滤工艺均使水中的MAP、TP及SRP大大降低;生物预处理和生物活性炭对水中MAP的去除效率高于对TP的去除效率;常规处理对原水中MAP的去除率超过90%,TP的去除率在80%以上.臭氧氧化对水中TP和SRP的影响不大,但是使MAP增加.试验原水经过净水处理后,水中可供细菌利用的磷源降低到很低的水平,说明处理后的水中磷源可能成为水中细菌生长的限制因子. 相似文献
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The field-experiment campaigns of the Asian Atmospheric Particulate Environment Change Studies (APEX-E1 in December 2000, -E2 in spring 2001, and -E3 in spring 2003) aimed at understanding Asian aerosols. Our sun/sky photometric measurements of atmospheric light have joined these campaigns by using multispectral photometers (CE-318-1 and -2, Cimel Electronique; and POM-100P, Prede) at Noto, Shirahama, and Fukue-jima, Japan. This paper focuses on aerosol retrieval during the APEX-E3 campaign. Aerosol optical thickness, Ångström exponent, single-scattering albedo and the refractive index derived from these ground-based measurements can be classified into three categories of aerosols: (1) an oceanic type of typical background aerosols over Japan, (2) an anthropogenic type, and (3) a soil-dust type. The data from APEX experiments demonstrate that aerosols over Japan exhibit complicated spatial and temporal features involving mixtures of compounds. 相似文献
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Sławomir Zakrzewski Katarzyna Majchrzycka Agnieszka Brochocka Krzysztof Makowski 《International journal of occupational safety and ergonomics》2013,19(2):164-170
In most industrial enterprises, hazardous factors are present in quantities exceeding permissible levels. Such a situation requires using antidust respiratory protection. It has been suggested, however, that filters for respirators are not assessed properly and that lab results might not be related to real filtering efficiency in industry. This article contains test results of some commercially available filtering half-masks, including the effect of loading with real dust, high humidity, high temperature, and a combination of loading with dust and high humidity on the half-masks’ performance. The results show that the effect of these factors is considerable and that a combination of loading with silica dust and exposing to high humidity can cause a complete loss of performance. 相似文献
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The primary aim of the study was to analyse the non-steady state of filtration for selected electrostatic filter materials designed for use in respiratory protective devices. The obtained results showed that the filtration process in electrostatic filters was dependent in the main on the following factors: type of the filter material, electrostatic field strength of the material, and the charge of the aerosol.To a lesser degree the filtration process depended on the sign of the charge and the relative humidity of the air. A significant correlation was found between the increase in the penetration and the decrease in breathing resistance while the filter was being loaded.The effect of resuspension (tearing off and re-deposition of dust agglomerates inside the filter) on the filtration process very significant. It was also observed that under certain conditions electrostatic filter materials lost their protection properties. 相似文献
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Juan Liu Guanjun Xu Xuejun Ruan Kejian Li Liwu Zhang 《Frontiers of Environmental Science & Engineering》2022,16(11):143
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