深海热液环境中存在着巨大的化学和热梯度, 快速剧烈的混合和生物过程产生了多种多样的矿物过程, 并培养了大量的化学合成微生物。 激光拉曼光谱非常适合于深海热液环境矿物过程的探测, 然而要对矿物与微生物作用过程进行研究, 还需要与荧光光谱技术进行联合, 针对此需求开展了原理验证实验研究。 在实验室搭建了一套拉曼-荧光联合光谱探测桌面系统, 利用一台双波长激光器同时作为拉曼光谱和荧光光谱的激发光源, 其中拉曼光谱采用532 nm波长, 荧光光谱采用266 nm波长, 双波长激光器发出的光束经分光镜分为两路, 经过后向散射光路收集的两路信号分别进入两个小型光纤光谱仪进行分光探测, 拉曼光谱采用QE65000光谱仪, 荧光光谱采用USB2000光谱仪, 通过软件可以方便的分别设置两个光谱仪的参数。 利用搭建的实验系统对海水和拟菱形藻样品进行探测, 分别获得了海水样品的SO2-4拉曼光谱和可溶性有机物(CDOM)荧光光谱, 拟菱形藻样品的类胡萝卜素拉曼光谱和类蛋白、 叶绿素等荧光光谱, 实验结果证明了研制小型拉曼-荧光联合光谱探测装置的可行性, 并为发展原位联合光谱探测装置提供了技术参考。

Great chemical and thermal gradient exists in deep sea hydrothermal vent environments, and rapid and turbulent mixing and biologic processes produce a multitude of diverse mineral phases and foster the growth of a variety of chemosynthetic micro-organisms. Raman spectrometer system is well suited to mineral speciation measurements and has been successfully used for deep sea hydrothermal environments detection so far. However, to further understand the interaction between mineral and microbial processes, a Raman system optimized for mineral identification that incorporates a fluorescence for microbial processes is necessary. In this paper, a combined Raman-fluorescence spectroscopy prototype was presented and some preliminary results were obtained. In this prototype, a double wavelength laser was used as the same excitation source for both Raman spectroscopy and fluorescence which worked at 532 and 266 nm, respectively. The laser was splitted into two paths based on wavelength and illuminated on the sample. The produced Raman and fluorescence signals were collected by a back-scattering optical set-up and coupled into a QE65000 and an USB2000 optical fiber spectrometer, respectively. With this prototype, we measured seawater and pseudo-nitzschia samples and got Raman and fluorescence spectra simultaneously for both samples, including sulfate Raman and CDOM fluorescence spectra in seawater sample, carotenoid Raman, proteoid and chlorophyll fluorescence spectra in pseudo-nitzschia sample. The results proved the feasibility of developing a compact Raman-fluorescence combined system for underwater detection.