Development of a Sensitive Lazer Spctrophotometric Environmental Monitoring Device Using Droplet Method

液滴法灵敏激光分光光度环境监测装置的研制

基本信息

批准号：
10650797
负责人：
KORENAGA Takashi
金额：
$ 2.56万
依托单位：
The University of Tokushima
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650797/
关键词：
droplet sampling device nitrogen dioxide lazer passive sampler microchip microfabrication サンプリング

项目摘要

We developed and used the passive sampling device to measure NOx in SOx in air pollution. In the present work we have changed the passive sampler method to the droplet method. Because the passive sampler is, however, not fit to the high sensitivity and precise analysis and, therefore, unable to monitor micro-amounts of variable toxic substances in long period exposure.To meet the solution of disadvantage, we adopted the Dasgupta's droplet method. We use the light-emitting diode and the optical fiber to analyze the droplet which used in the experiment is the cylindrical chamber. In the center of the chamber there is a stainless steel tube. It is used to deliver the solution. And the tip of a stainless tube always keeps the droplet dripping. The gas stream is introduced into the cylindrical chamber at the top, from two oppositely located gas inlets, to achieve more symmetric flow profile around the droplet. Then the droplet collects the gas and is changed the color. The light from a high brightness LED illuminates the droplet. On the diametrically opposite side, the transmitted light is conducted by a plastic optical fiber to a photodiode equipped with an interface filter. A reference photodiode is placed at the back plane of the LED to provide a dual-beam referenced detection arrangement. Absorbance is computed as -log[ (Id-Id')/(Ir-lr') ] +Ko where Id and Ir are the respective photocurrents generated by the detector and the reference photodiode, Id' and Ir' are the corresponding dark currents, and Ko is an offset constant that compensates for the inequality between the intensities of the reference beam and the probe beam directed to the drop.Our purpose and goal are the application of the recent micromachining techniques to the droplet method. A microchip of several centimeter square can collect and analyze the gas sample. Also, microfabrication of the droplet method will give the smallest analysis device which can be applicable to various environmental samples.

我们开发并使用了被动抽样装置在空气污染中测量Sox中的NOX。在目前的工作中，我们将被动采样器方法更改为液滴方法。但是，由于被动采样器不符合高灵敏度和精确的分析，因此无法在长期暴露中监测可变有毒物质的微观启动。为了满足劣势的解决方案，我们采用了Dasgupta的液滴方法。我们使用发光二极管和光纤分析实验中使用的液滴是圆柱形腔室。在腔室的中心有一个不锈钢管。它用于提供解决方案。不锈钢管的尖端总是保持滴水。从两个相对位置的气体入口，将气流引入顶部的圆柱室，以实现液滴周围更对称的流动剖面。然后液滴收集气体并改变颜色。高亮度的光线导致液滴照亮。在直径相对的一侧，通过塑料光纤向配备界面滤波器配备的光电二极管进行透射光。将参考光电二极管放置在LED的背面，以提供双光束引用的检测排列。吸光度计算为-log [（id-id'）/（ir-lr'）] +KO，其中ID和IR是检测器和参考光电二极管，ID'和ir'的相应光电，是相应的深色电流，KO是相应的偏移常数，它是一个偏移常数，可补偿型号和探测器之间的不平等现象，并且在参考光束之间的不平等范围是对参考束的不平等现象。液滴方法的技术。几厘米平方的微芯片可以收集和分析气体样品。同样，液滴方法的微加工将提供最小的分析设备，该设备可适用于各种环境样品。