基的开放途径光谱检测:宽带腔增强吸收光谱 (BBCEAS) 和与法布里-佩罗干扰仪 (BBCEAS-FP) 结合的BBCEAS之间的比较
Callum E Flowerday1, Ryan Thalman2, Matthew C Asplund1
1Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States.
Analytical chemistry
|May 29, 2025
概括
测量大气中的基 (OH) 很困难. 本研究介绍了宽带腔增强吸收光谱 (BBCEAS) 仪器,为OH提供了改进的场测量能力.
科学领域:
- 大气化学 大气化学
- 频谱学是一种光谱学.
- 环境监测 环境监测
背景情况:
- 基 (OH) 是主要的大气氧化剂,对空气质量和气候至关重要.
- 测量OH是具有挑战性的,因为它的度很低,在大气中的寿命很短.
- 现有的现场测量技术,如LIF-FAGE和CIMS具有局限性.
研究的目的:
- 评估两种新型宽带腔增强吸收光谱 (BBCEAS) 仪器的性能,用于测量大气OH.
- 将BBCEAS与现有的现场测量技术进行比较.
- 评估气溶和流对BBCEAS性能的影响.
主要方法:
- 使用了两个BBCEAS仪器:一个带有CCD探测器,另一个带有法布里-佩罗干扰仪 (BBCEAS-FP).
- 采用开放路径配置与低损耗光学来测量空洞反射率.
- 在测试和校准中使用丁火焰作为受控的OH源.
主要成果:
- 在BBCEAS仪器实现了1.5 × 107分子/cm3的超值1小时检测极限.
- 使用高斯-赫米特过器提高了检测极限,达到4.6 × 106分子/厘米3.
- 在BBCEAS-FP证明了1.5×107分子/厘米的可比检测极限,提供了一个更具成本效益和便携性的解决方案.
结论:
- BBCEAS仪器显示出准确和特定的大气OH场测量的希望.
- BBCEAS-FP为OH监控提供了一个可行的,更容易获得的替代方案.
- 进一步的研究应该调查不同大气条件下的真实世界性能.
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