Shen Z X, Cao J J, Zhang X Y, Arimoto R, Ji J F, Balsam W L, Wang Y Q, Zhang R J, Li X X
Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'An 710049, China.
Sci Total Environ. 2006 Aug 31;367(2-3):899-907. doi: 10.1016/j.scitotenv.2006.01.003. Epub 2006 Feb 17.
Diffuse reflectance spectrometry was used to study iron-oxide minerals and to investigate the reflectance characteristics of eolian dust collected during the spring of 2001 and 2002 on bulk filters from three sites in northern China. The first derivatives of the reflectance spectra were consistent with signals from two iron-oxide minerals, hematite and goethite, at wavelengths of 565 and 435 nm, respectively, and these values varied with the iron concentrations in the samples. The percent reflectances for the yellow, orange and red bands increased with the iron concentrations and with the first derivative values representing hematite and goethite while those for violet, blue and green bands decreased correspondingly. The results show that iron-oxide minerals play an important role in determining the aerosol particles' color and reflectance properties. Moreover, the relative amounts of the two iron-oxides in Asian dust apparently differ from those in African dust, suggesting that the iron-oxides may provide another tool for tracing the origins of eolian dust on a global scale.
漫反射光谱法用于研究氧化铁矿物，并调查2001年和2002年春季在中国北方三个地点的大容量过滤器上收集的风尘的反射特性。反射光谱的一阶导数分别与波长为565和435nm的两种氧化铁矿物赤铁矿和针铁矿的信号一致，并且这些值随样品中的铁浓度而变化。黄色、橙色和红色波段的反射率百分比随铁浓度以及代表赤铁矿和针铁矿的一阶导数值增加，而紫色、蓝色和绿色波段的反射率百分比则相应降低。结果表明，氧化铁矿物在决定气溶胶颗粒的颜色和反射特性方面起着重要作用。此外，亚洲沙尘中两种氧化铁的相对含量明显不同于非洲沙尘中的相对含量，这表明氧化铁可能为在全球范围内追踪风尘来源提供另一种工具。
