OH and H2SO4 Measurements

本项目的目标是利用质谱学技术测量大气光解的几种重要产物，包括羟基自由基、气相硫酸和甲烷磺酸。此外，用于进行这些测量的仪器将进行改装，以使舰载和飞机研究成为可能。最近对质谱学测量技术和NOAA长程激光吸收技术进行了非正式的相互比较，结果表明这两种仪器测量到的OH浓度相似。然而，测得的羟基自由基浓度一直远低于模型预测。为了研究这些差异，这些科学家将于1993年夏天在科罗拉多州参加另一项羟基自由基相互作用和光化学实验。还将进行第二项研究，以确定植被和其他近地面损失机制对羟基自由基浓度的可能影响。还将对现有系统进行修改，以便有可能在移动平台上进行测量，以便今后进行研究。

The objective of this project is to measure several important products of atmospheric photolysis including the hydroxyl radical, and gas phase sulfuric and methanesulfonic acids using a mass spectrometric technique. In addition , the instrument used to perform these measurements will be modified to make possible shipboard and aircraft studies. A recent informal intercomparison between the mass spectrometric measurement technique and a NOAA long path laser absorption technique resulted in similar concentrations of OH being measured by both instruments. The measured hydroxyl radical concentrations were however, consistently well below model predictions. In order to investigate these discrepancies these scientists will participate in an additional hydroxyl radical intercompaion and photochemistry experiment in Colorado during the summer of 1993. A second study to isolate possible effects of vegetation and other near-ground loss mechanisms on hydroxyl radical concentration will also be undertaken. Modifications to the present system would also be undertaken to make possible measurements on a mobile platform for future studies.