Jimenez Jorge, Claiborn Candis, Larson Timothy, Gould Timothy, Kirchstetter Thomas W, Gundel Lara
EULA-Chile, Environmental Sciences Center, University of Concepción, Concepción, Chile.
J Air Waste Manag Assoc. 2007 Jul;57(7):868-73. doi: 10.3155/1047-3289.57.7.868.
In this study, a correction was developed for the aethalometer to measure real-time black carbon (BC) concentrations in an environment dominated by fresh diesel soot. The relationship between the actual mass-specific absorption coefficient for BC and the BC-dependent attenuation coefficients was determined from experiments conducted in a diesel exposure chamber that provided constant concentrations of fine particulate matter (PM; PM(2.5); PM < 2.5 microm in aerodynamic diameter) from diesel exhaust. The aethalometer reported BC concentrations decreasing with time from 48.1 to 31.5 microg m(-3) when exposed to constant PM(2.5) concentrations of 55 +/- 1 microg m(-3) and b(scat) = 95 +/- 3 Mm(-1) from diesel exhaust. This apparent decrease in reported light-absorbing PM concentration was used to derive a correction K(ATN) for loading of strong light-absorbing particles onto or into the aethalometer filter tape, which was a function of attenuation of light at 880 nm by the embedded particles.
在本研究中，开发了一种针对黑碳仪的校正方法，用于在以新鲜柴油机烟灰为主的环境中测量实时黑碳（BC）浓度。通过在柴油机暴露舱中进行的实验，确定了BC的实际质量比吸收系数与BC相关衰减系数之间的关系，该暴露舱可提供来自柴油机尾气的恒定浓度的细颗粒物（PM；PM(2.5)；空气动力学直径小于2.5微米的PM）。当暴露于来自柴油机尾气的55±1微克/立方米的恒定PM(2.5)浓度和b(scat)=95±3兆米(-1)时，黑碳仪报告的BC浓度随时间从48.1下降至31.5微克/立方米。报告的吸光PM浓度的这种明显下降被用于推导针对强光吸收颗粒加载到黑碳仪滤带上或进入滤带的校正系数K(ATN)，它是嵌入颗粒在880纳米处光衰减的函数。
