紫外拉曼光谱非接触探测土壤表面化学毒剂模拟剂

Non-contact Detection of Chemical Warfare Agent Simulants on Soil Surface by UV Raman Spectrum

化学侦察要求对地面沾染的可疑物质进行快速探测和分析。由于土壤成分复杂,采用常规拉曼光谱仪检测地面沾染物时存在检测时间长、荧光干扰大、特征信号弱的问题。采用激光波长为257 nm的紫外拉曼光谱探测系统对土壤表面的化学毒剂模拟剂甲基膦酸二甲酯(DMMP)、磷酸三乙酯(TEP)和2-氯乙基乙基硫醚(2-CEES)进行了检测。通过分子指纹峰确认和官能团归属分析,证明该探测系统可对土壤表面的模拟剂进行准确识别和连续监测,可在10 s内检测到0.1 g/m^(2)的TEP,达到了美军对于地面沾染毒剂最低检出限0.5 g/m^(2)的要求。实验结果表明,257 nm紫外拉曼光谱探测系统相对于近红外和可见光波段拉曼光谱仪检测表面沾染物具有荧光干扰小、灵敏度高、响应速度快和非接触实时探测的优势,因此在军事和公共安全领域有良好的应用前景。

Chemical reconnaissance requires rapid detection and analysis of the suspected contaminants on the ground.Due to the complexity of soil composition,the problems of long detection time,large fluorescence interference and weak characteristic signals exist when conventional Raman spectrometers are used to detect ground contaminants.In this paper,the UV Raman detection system with 257 nm laser wavelength was used to detect the chemical warfare agent simulants dimethyl methylphosphate(DMMP),triethyl phosphate(TEP)and 2-chloroethyl ethyl sulfide(2-CEES)on the soil surface.Through the molecular fingerprint peak confirmation and functional group attribution analysis,the detection system was proven to be able to accurately identify and continuously monitor the surface contaminants of soil,and TEP of 0.1 g/m^(2) could be detected within 10 s,which met the U.S.military requirement of the minimum detection limit of ground contaminated agents of 0.5 g/m^(2).The experimental results show that the 257 nm UV Raman spectroscopy detection system has the advantages of little fluorescence interference,high sensitivity,fast response and non-contact real-time detection compared with the near-infrared and visible band Raman spectrometer,so it has a good application prospect in the field of military and public safety.