Determination of Be and Al for Source Region Identification of White Nephrite Using Laser-Induced Breakdown Spectroscopy
-
摘要: 利用自行搭建的激光诱导离解光谱仪分析54块新疆、青海、俄罗斯产地的透闪石白玉样品,提出通过检测Be、Al元素来区分白玉产地的方法。使用波长1064 nm的激光器激发样品,4CCD光谱仪采集光谱,为避免外界条件干扰,以透闪石白玉中含量比较固定的Si元素作为内标元素测量原子谱线强度比值IBe/ISi、IAl/ISi,分别代表Be、Al元素的含量变化,重复测量10次的相对标准偏差 (RSD) 3%。结果表明,新疆白玉的IBe/ISi为0.3~0.6,IAl/ISi为0.1~0.4;青海白玉IBe/ISi 0.1,IAl/ISi 0.2,显示出低Be低Al的明显特征;俄罗斯白玉的IBe/ISi分为高值和低值两个区域,部分样品的IBe/ISi0.7,指示Be的含量较高,另一部分样品的IBe/ISi为0.1~0.5,略低于新疆白玉。研究显示Be、Al元素特别是Be元素具有较好的产地指示意义,激光诱导离解光谱技术用于鉴别白玉产地有着较好的推广前景。Abstract: A method to identify the source region of white nephrite by detecting element Be and Al with laser-induced breakdown spectroscopy is proposed to measure chemical compositions of 54 white nephrite samples collected from Xinjiang, Qinghai, and Russia. A laser excitation wavelength of 1064 nm was used and the spectrum was collected by a spectrometer with 4CCD. Multiple measurements were taken for each sample in order to meet the relative standard deviation (RSD) 3%. Elemental Si was applied as the internal standard, because the content of Si in white nephrite is almost invariable. By doing this, the intensity ratios of IBe/ISi and IAl/ISi can directly represent the contents of element Be and Al in samples. The results indicate that the IBe/ISi ratios of Xinjiang samples are high, ranging from 0.3 to 0.6, with IAl/ISi ratios of 0.1 to 0.4. The Qinghai samples had the most obvious features of very low Be and Al, such as the IBe/ISi ratios being lower than 0.1 and IAl/ISi ratios lower than 0.2. The Russian samples had two different distribution areas. IBe/ISi ratios of some samples were higher than 0.7, indicating high levels of Be. However, some IAl/ISi ratios were between 0.1 and 0.5, which were slightly lower than the Xinjiang samples with a little overlap. The experimental results show that elemental Be and Al, especially elemental Be have an obvious origin character The laser-induced breakdown spectroscopy had a good application value for nephrite source region identification.
-
-
计量
- 文章访问数: 344
- PDF下载数: 2
- 施引文献: 0