Heeres Paul, Setiawan Rineksa, Krol Maarten Cornelis, Adema Eduard Hilbrand
Meteorology and Air Quality, Wageningen University and Research, Droevendaalsesteeg 4, 6708 PB, Wageningen, The Netherlands.
J Environ Monit. 2009 Dec;11(12):2216-21. doi: 10.1039/b914023a. Epub 2009 Sep 18.
This paper describes two new methods for the determination of NO(2) in the ambient air. The first method consists of free hanging filters with a diameter of 2.5 cm as passive samplers. The filters are impregnated with triethanolamine to bind NO(2). With standard colorimetrical analysis, the amount of NO(2) on the filters is determined. The second method is performed with fritted bubblers filled with Saltzman reagent, where, with a special procedure the absorption efficiencies of the bubblers are determined using ambient air, without the use of standard gases and electronic analytical instruments. The results of the bubblers are used to calibrate the free hanging filters. The two methods were applied simultaneously in the city of Yogyakarta, Indonesia. The methods are inexpensive and very well suited for use in low-budget situations. A characteristic of the free filter is the Sampling Volume, SV. This is the ratio of the amount of NO(2) on the filter and the ambient concentration. With the filter used in this study, the amount of triethanolamine and exposure time, the SV is 0.0166 m(3). The sampling rate (SR) of the filter, 4.6 cm(3)/s, is high. Hourly averaged measurements are performed for 15 hours per day in four busy streets. The measured amounts of NO(2) on the filters varied between 0.57 and 2.02 microg NO(2), at ambient air concentrations of 32 to 141 microg/m(3) NO(2). During the experiments the wind velocity was between 0.2 and 2.0 m/s, the relative humidity between 24 and 83 % and the temperature between 295 K and 311 K. These variations in weather conditions have no influence on the uptake of NO(2).
本文介绍了两种测定环境空气中二氧化氮（NO₂）的新方法。第一种方法是使用直径为2.5厘米的自由悬挂式滤膜作为被动采样器。滤膜用三乙醇胺浸渍以结合NO₂。通过标准比色分析确定滤膜上NO₂的含量。第二种方法是使用装有萨尔茨曼试剂的烧结鼓泡器，通过一种特殊程序，在不使用标准气体和电子分析仪器的情况下，利用环境空气测定鼓泡器的吸收效率。鼓泡器的结果用于校准自由悬挂式滤膜。这两种方法同时应用于印度尼西亚日惹市。这些方法成本低廉，非常适合在预算有限的情况下使用。自由滤膜的一个特性是采样体积（SV）。这是滤膜上NO₂的量与环境浓度的比值。使用本研究中的滤膜、三乙醇胺的量和暴露时间，SV为0.0166立方米。滤膜的采样率（SR）为4.6立方厘米/秒，较高。每天在四条繁忙街道上每小时进行15小时的平均测量。在环境空气浓度为32至141微克/立方米NO₂时，滤膜上测得的NO₂量在0.57至2.02微克NO₂之间变化。实验期间，风速在0.2至2.0米/秒之间，相对湿度在24%至83%之间，温度在295 K至311 K之间。这些气象条件的变化对NO₂的吸收没有影响。
