A trial construction of a new instrument for a high sensitive determination on liquid surface.

(1)目的基于激光双光子电离技术，建立一种能在几个纳米厚度的液体表面进行高灵敏度测定的新仪器。还应将其应用于各种项目。(2)结果（1）设计与施工。/购买了一台单色仪、一个压电控制器和各种光学部件，设计并建造了一台新仪器。该仪器的目的是提高灵敏度和空间分辨率相比，以前的。(2)评价所构建的工具。/通过改变溶液的表面压力和pH值，利用新仪器测量了芘衍生物的双光子电离信号。测定了这些化合物的pKa值，发现它们在溶液中和表面上的pKa值不同。测定了几种化合物在水面上的分析曲线。(3)适用于极小区域内的高灵敏度测定。/我们尝试用微电极测量信号电流，灵敏地测定水和玻璃表面的几种芳香分子。蒽的检出限为12 fmol。(4)皮秒激光的应用。/为了确定激光脉冲宽度的影响，我们尝试使用皮秒NdYAG激光器作为激发源。我们已经发现，当1064 nm光束与355 nm光束重叠时，灵敏度增加。(5)激光诱导荧光技术的评价。/我们还构建了一个基于共聚焦荧光显微镜的新仪器。对卟啉化合物的荧光光谱和分子分布进行了测定，表明该仪器具有表面特异性。

(1) Purpose Based on the laser two-photon ionization technique, a new instrument should be constructed for high sensitive determination on liquid surface of a few nanometer thickness. Application to various projects should also be carried out.(2) Results(1) Design and construction. /// A new instrument was design and constructed with a purchase of a monochromator, a piezo controller and various optical parts. The instrument was aimed to improve sensitivity and spatial resolution compared to the previous one.(2) Evaluation of the constructed instrument. /// The two-photon ionization signals of pyrene derivatives were measured using the new instrument by varying the surface pressure and pH of the solution. The value of pKa of these compounds were determined and found to be different in solution and on surface. The analytical curves of several compounds on water surface were also determined.(3) Application to high sensitive determination in a very small region. /// We have tried to determine several aromatic molecules on surface of water and glass sensitively using a micro electrode to measure the signal currents. The detection limit of anthracene was 12 fmol.(4) Application of a pico-second laser. /// In order to determine effects of the laser pulse width, we tried to use a pico-second NdYAG laser for an excitation source. We have found that the sensitivity increased when the 1064 nm beam was overlapped with the 355 nm beam.(5) Evaluation of the laser-induced fluorescence technique. /// We have also constructed a new instrument based on the confocal fluorescence microscope. The fluorescence spectrum and molecular distribution of porphyn compounds have been determined to indicated the new instrument is surface specific.