A development of photolysis system for NO_2 measurement on board the aircraft

机载NO_2光解测量系统的研制

• 批准号: 07554079
• 负责人: KOIKE Makoto
• 金额: $ 1.34万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07554079/
• 关键词: Reactive nitrogen; Nitrogen dioxide; Nitric oxide; Photolysis converter; Aircraft measurement; Tropospheric ozone; 総反応性窒素酸化物

NO_x (NO+NO_2) plays a critical role on the phtochemical ozone (03) production in the troposhere. In this study, a prototype system for NO_2 detection has been developed for a future application on the aircraft measurement.The UV Photolysis system to convert NO_2 into NO is the key of the instrument, beause the NO detection system has been already developed. We have used a metal halogen lamp as a light source. We have also used a photolysis cell of which wall was coated with reflective aluminum to increase the photolysis rate in the cell. We have also developed a Teflon valve to control a pressure inside the photolysis cell. As a result, a conversion efficiency of about 50% was obtained with a residence time inside of the cell of 1-2 sec. A conversion efficiency can be higher when pressure inside the cell is kept higher, however other molecules such as N_2O_5 was found to also be photodissociated. In addition, Uv in the wavelength shorter than 320nm should be cut using optical filter to prevent the photodissociation of HNO_3. Based on these results, we plan to develop a NO_2 detection system which can be used on board the aircraft.

NO_x（NO+NO_2）对对流层光化学臭氧（03）的产生起着至关重要的作用。本研究开发了NO_2检测原型系统，以供未来在飞机测量上的应用。由于NO检测系统已经开发出来，将NO_2转化为NO的紫外光解系统是该仪器的关键。我们使用金属卤素灯作为光源。我们还使用了光解池，其壁涂有反光铝，以提高池内的光解速率。我们还开发了聚四氟乙烯阀门来控制光解池内的压力。结果，在电池内部的停留时间为1-2秒的情况下获得了约50%的转换效率。当电池内部的压力保持较高时，转换效率会更高，但发现其他分子（例如 N_2O_5）也会发生光解。另外，应使用滤光片滤除波长小于320nm的Uv，以防止HNO_3的光解离。基于这些结果，我们计划开发一种可在飞机上使用的NO_2检测系统。

项目成果

M.Koike: "Correlations of NO_y with O_3 and CO over the Western Pacific during PEM-West B" Proceedings for Quadrennial Ozone Symposium. (in press). (1997)

M.Koike：“PEM-West B 期间西太平洋 NO_y 与 O_3 和 CO 的相关性”四年一度臭氧研讨会论文集。

M.Koike: "Aircraft measurements of total reactivenitrogen and ozone over the western Pacific in winter" Atmos.Environ.30. 1631-1640 (1996)

M.Koike：“冬季西太平洋上空总活性氮和臭氧的飞机测量”Atmos.Environ.30。

M. Koike: "Ratios of reactive nitrogen over the Pacific during PEM-West A." J. Geophys. Res.101. 1829-1851 (1996)

M. Koike：“PEM-West A 期间太平洋上空活性氮的比率。”

Y. Kondo: "Reactive nitrogen over the Pacific ocean during PEM-West A" J. Geophys. Res.101. 1809-1828 (1996)

Y. Kondo：“PEM-West A 期间太平洋上空的活性氮”J. Geophys。

M.Koike, Y.Kondo, S.Kawakami, H.Nakajima, G.L.Gregory, G.W.Sachse, H.B.Singh, E.V.Browell, J.T.Merrill, and R.E.Newell: "Reactive nitrogen and its correlations with O_3 and CO over the Western Pacific during PEM-West B" J.Geophys.Res.(in press). (1997)

M.Koike、Y.Kondo、S.Kawakami、H.Nakajima、G.L.Gregory、G.W.Sachse、H.B.Singh、E.V.Browell、J.T.Merrill 和 R.E.Newell：“西太平洋期间的活性氮及其与 O_3 和 CO 的相关性