Development of Atmospheric Chemistry Instrumentation

9417061斯特德曼这个由四部分组成的研究项目旨在提高测量大气物种在地面和大气之间的通量的能力。部分由丹佛大学开发的探测系统将被进一步开发和调查，以确定这些通量的能力。第一部分：将长程紫外(LPUV)光谱与长程红外(LPIR)光谱相结合，用于测定各种物种的通量。将尝试两种新的系统方法。两者都利用了这样一个事实，即基于角立方体的现代FTIR系统有两个光输入端口，系统本质上对两者之间的强度差异做出反应。梯度法测量通量，由于其灵敏度依赖于微小差值的测量，可以利用这一能力直接测量物种的梯度。来自同一光源的两束光束将被设计成在两个不同高度穿过路径，以便在FTIR中组合以进行差异测量。同一系统的另一种配置将把两束光束绕过疑似发射源的两侧。这应该可以自动减去可疑污染源中除排放量以外的所有排放量。FTIR是从以前的支持中获得的，然而，望远镜、镜子、软件、实验协议等将在该计划下开发。长期目标是对大气物种的排放和沉积进行更可靠的测量。第二部分：现有的快速响应、现场全硫监测仪将在响应速度和灵敏度方面进行优化。它将被用来通过涡旋相关技术来研究通量。一些通量研究将与国家大气研究中心(NCAR)大气表面湍流交换研究(ASTER)设施合作进行。第三部分：建立了一种常压流动体系，自由基测定器对过氧化氢(HO2)和有机过氧基(RO2)的浓度作出了响应。这种装置被命名为Perca(使用化学放大的过氧基检测器)，也被证明对直到C8的许多碳氢化合物和含氧碳氢过氧基都有反应。根据该计划的这一部分，将进行的研究是研究干扰并开发一种便携式校准系统，用于制备含有已知浓度的自由基的标准。海洋地区大气氯光化学的潜力已经成为一个有趣的科学争论的主题。这些研究人员将开发一种高灵敏度的系统，该系统将检测原子氯，从而可能检测到微量的卤胺，这可能是在氯光化学发生时形成的。

9417061 Stedman This four part research project is designed to improve the ability to measure the flux of atmospheric species between the ground and the atmosphere. Detection systems developed, in part, at the University of Denver, will be further developed and investigated in terms of their ability to determine these fluxes. Part 1. Long-path UV (LPUV) spectroscopy will be coupled with long-path IR (LPIR) spectroscopy and used to determine the fluxes of various species. Two new system approaches will be attempted. Both make use of the fact that modern corner-cube based FTIR systems have two input ports for light, and the system responds intrinsically to the intensity difference between the two. The gradient method for flux measurement, which depends on the measurement of small differences for its sensitivity, can make use of this ability to directly measure species gradients. Two light beams from the same source will be designed to traverse the path at two different altitudes to be combined in the FTIR for the difference measurement. Another configuration of the same system will send the two beams around two sides of a suspected emission source. This should achieve automatic subtraction of all but emissions from the suspect source. The FTIR is available from previous support, however, the telescopes, mirrors, software, experimental protocols, etc. will be developed under this program. The long-term goal is more reliable measurements of emission and deposition of atmospheric species. Part 2. An available fast-response, in-situ, total sulfur monitor will be optimized for response speed and sensitivity. It will be used for flux studies by means of the eddy-correlation technique. Some of the flux studies will be carried out in collaboration with the National Center for Atmospheric Research (NCAR) Atmosphere Surface Turbulence Exchange Research (ASTER) facility. Part 3. An atmospheric pressure, flow system, free radical dete ctor has been developed and shown to respond to concentrations of hydroperoxyl (HO2) and organic peroxyl (RO2) radicals. This apparatus, named PERCA (PEroxy Radical detector using Chemical Amplification) has also been shown to respond to a number of hydrocarbon and oxygenated hydrocarbon peroxy radicals up to C8. The research to be performed under this portion of the program is to study interferences and to develop a portable calibration system for preparing standards containing known concentrations of free radicals. Part 4. The potential for atmospheric chlorine photochemistry in oceanic regions has become the subject of an interesting scientific controversy. These researchers will develop a high- sensitivity system that will detect atomic chlorine, thus potentially detecting traces of halogen amines, which may be formed if chlorine photochemistry is taking place.