生物气溶胶的激光光谱识别研究

A Study of Laser Spectra Identification on Bioaerosols

生物气溶胶对人类的健康、动植物的生长可构成很大的威胁。生物气溶胶的激光光谱识别和荧光雷达探测研究有利于人类与传染疾病作斗争。有条件采样单位于生物气溶胶荧光光谱分析仪在荧光收集系统之后巧妙地把粒子的弹性散射光和未经色散的荧光按产生的时间先后分成两个部分。光谱仪有条件采样过程可降低数据采集和数据处理速率，提高信噪比。有条件触发单粒子生物气溶胶荧光光谱分析仪的光源为一台连续的Ar＋激光器和一台四倍频Nd：YAG激光器，可得到紫外荧光信息，扩大了应用范围。该仪器必须满足严格的时序条件和逻辑条件。利用紫外激光诱导荧光雷达探测技术可进行生物气溶胶及生物战剂的识别研究。一台紫外－荧光雷达系统，当探测距离为3000m时，浓度探测极限为500mg／m3。一种长距离生物传感探测系统可对正在运动中的气溶胶云团进行测距、探测和跟踪，跟踪高度可达30km。

Biological aerosol can pose it threat of plants and animals. Thus the study of laser spectra identification and fluorescence lidar detection on bioaerosols could be useful for combating the spread of diseases in plants, animals and human race.A conditional-sampling spectrograph detection may cleverly divide elastic scattering and total fluorescence into two parts respectively in the sequence of time. This conditionalsampling procedure reduces data-handling rates and increases the signal-noise ratio. An argon ion laser and a 266 nm Q-switched Nd:YAG laser are used by a conditional- firing fluorescence spectrum analyzer for individual airborne particles. UV-fluorescence spectra of biological airborne particles can be analyzed with this spectrum analyzer, therefore, it is widely used for UV-fluorescence analysis. Of course, a strange timing diagram and some logic conditions must be needed by this spectrum analysis system.A UV-fluorescence lidar system is used for identification study of biological aerosols and bio-warfare agent. The tests with this lidar system indicate a detection limit of approximately 500 mg/m3 at a range of 3000 m. A long range-biological stand-off detection system can range, detect and track biological clouds while on the move at distance up to 30 km.