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131.
一套民用固体燃料燃烧大气污染物排放测试系统的搭建和评测 总被引:2,自引:0,他引:2
为研究民用固体燃料燃烧的大气污染物排放特征,设计了一套箱式稀释采样测试系统.相比于常用的烟罩法和烟道采样法,该系统能减小环境空气中颗粒物对测试结果的影响,同时收集了炉具泄漏的烟气,能更准确获得固体燃料燃烧的大气污染物排放水平.本文介绍了该系统的设计思路、主要结构组成和测试系统的性能评估结果.评估结果表明:进气经过滤后颗粒物浓度显著下降至约1μg·m-3,远小于燃烧过程中排放的颗粒物浓度(约100μg·m-3),有效减少环境空气中颗粒物对测试结果的干扰;使用箱式法测得PM_(2.5)、SO2和NOx排放因子结果均高于箱体敞开的对照组测试,证明箱式法收集测试了燃烧时泄漏至室内的污染物,有效减少污染物泄漏造成的误差.利用该系统测试了12种常见民用煤和3种生物质燃料燃烧PM_(2.5)、SO2、NOx等污染物排放水平,其中民用煤PM_(2.5)、SO2和NOx排放因子分别为0.23~3.40 mg·g~(-1)、0.48~6.15 mg·g~(-1)和0.16~1.09 mg·g~(-1),生物质燃料的PM_(2.5)、SO2和NOx排放因子分别为6.26~39.76 mg·g~(-1)、0.04~0.23 mg·g~(-1)和0.05~0.76 mg·g~(-1). 相似文献
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H. Plaisance S. Sauvage P. Coddeville R. Guillermo 《Environmental monitoring and assessment》1998,51(3):657-671
The variability in performance of three precipitation sensor types, mounted on three identical wet-only collectors, has been compared for eight months at a single site. The catch efficiencies, determined from the sample volumes, are relatively high for these three apparatuses, since they exceed 89% on average. The recorded data of openings and closings of collector lids reveal that the highest losses of collection efficiency, observed for rainfalls of low intensity and low amount, are largely imputable to design and running characteristics of each sensor. Ionic compositions between the samples of these three collectors are relatively close, although significant differences are especially found for H+, Ca2+, Mg2+ and K+, suggesting that these apparatuses are differently exposed to the dry deposition of soil particles. The RS 85 sensor seems to be the most suitable one of the three, since it ensures a high catch efficiency for all rain types and tends to limit the exposures of funnel to the dry deposition. 相似文献
136.
Michael Lavin 《Environmental and Ecological Statistics》1999,6(1):47-57
Ranked set sampling can be useful when measurements are expensive but units from the popu- lation can be easily ranked. In this situation one may draw k units from the population, rank them, select one on which to make the expensive measurement, draw another k units, rank them, select one, and so on. The method was originally suggested by McIntyre (1952) in connection with pasture yields and is obviously applicable in other situations as well. Dell and Clutter (1972) and Patil et al. (1994) explain the basics from a classical point of view. Our aim is to examine the procedure from a Bayesian point of view, determine whether ranked set sampling provides advantages over simple random sampling and explore some optimality questions 相似文献
137.
Gerald Spindler Konrad Müller Hartmut Herrmann 《Environmental science and pollution research international》1999,6(2):89-94
Aerosol filter samples have been collected nearby the industrialised basin of Leipzig in Saxony (Germany) at the research station Melpitz of the Institut für Troposphärenforschung e.V. (IfT). Time series (1992–1998) and a three year comparison (1995–1997) of two different aerosol filter sampling systems, the Sierra-Andersen-PM 10 high volume sampler (daily sample, PM 10 inlet) and the Rupprecht and Patashnik Co. Inc. Model Partisol 2000 (weekly sample, PM 10 and PM 2.5 inlet) are presented and discussed. The comparison of the different sampling systems and strategies yields small differences between the daily and weekly samples for mass and different ions, which may be influenced by sampling duration and flow rates. A general trend of change in aerosol composition was observed: Soot and Sulphate concentrations decreased whereas Nitrate and Ammonium concentrations increased. During summers the mass of coarse particles is higher than in other seasons. One reason could be found in the occurence of longer periods of dry ground surfaces enabling reemission of crustal and biological material. The time series have been integrated in a longer historical aerosol mass trend for Saxony and do show a good agreement. Since 1990 a significant downward trend in gravimetric mass concentration was found. 相似文献
138.
Ozone measurements along vertical transects in the Alps 总被引:1,自引:1,他引:0
Herbert Werner Manfred Kirchner Gerhard Welzl Markus Hangartner 《Environmental science and pollution research international》1999,6(2):83-87
To investigate the vertical profiles of air pollutants in the boundary layer, aircraft and balloon-born measurements and measurements
using a cable car as an instrument platform have been performed in different parts of the Alps. This on-line monitoring of
atmospheric pollutants requires expensive and sophisticated techniques. In order to control ambient air quality in remote
regions, where no infrastructure like power supply is available, simple instruments are required. The objective of this study,
which was coordinated and evaluated by the GSF-Forschungszentrum für Umwelt und Gesundheit was first, to investigate the vertical
distribution of ozone in different parts of the Alps and secondly, in addition to continuous analyser measurements, to test
monitoring by means of two types of passive samplers. The selection of these samplers — one for one week use and another one
for two week application — was based on a passive sampler intercomparison done in a preliminary study one year earlier. 相似文献
139.
周灵辉 《环境监测管理与技术》2004,16(3):38-40
运用数理统计学的分层抽样法对南京市2001年-2003年小型餐饮娱乐服务业废水中具有相关性的主要污染因子的排放浓度进行了统计,并计算出排放系数,提出用计算的废水排放系数征收小型餐饮娱乐服务业的排污费,实例表明,在该行业运用这一方法征收排污费是可行的。 相似文献
140.
长江江豚(Neophocaena asiaeorientalis)是唯一淡水生活的鼠海豚类,近年来种群数量严重下降,2013年被世界自然保护联盟红色名录列为“极度濒危”,2021年升级为我国国家一级重点保护野生动物,2022年种群有所恢复。长江江豚是长江生态系统健康的指示物种,我国科学家自20世纪50年代开始监测至今,监测方法不断更新完善,对长江江豚现状的了解也越来越充分。该文回顾了截线抽样法、水下被动声学及自动实时监测系统、无人机、环境DNA等监测方法的应用及取得的成效,分析监测方法存在的不足,预测技术发展趋势,提出改进建议,为长江江豚的监测及保护提供基本参考。 相似文献