Abstract:
Mercury (Hg) researchers have made progress in understanding atmospheric Hg, especially with respect to oxidized Hg (HgII) that can represent 2 to 20% of Hg in the atmosphere. Knowledge developed over the past ∼10 years has pointed to existing challenges with current methods for measuring atmospheric Hg concentrations and the chemical composition of HgII compounds. Because of these challenges, atmospheric Hg experts met to discuss limitations of current methods and paths to overcome them considering ongoing research. Major conclusions included that current methods to measure gaseous oxidized and particulate-bound Hg have limitations, and new methods need to be developed to make these measurements more accurate. Developing analytical methods for measurement of HgII chemistry is challenging. While the ultimate goal is the development of ultrasensitive methods for online detection of HgII directly from ambient air, in the meantime, new surfaces are needed on which HgII can be quantitatively collected and from which it can be reversibly desorbed to determine HgII chemistry. Discussion and identification of current limitations, described here, provide a basis for paths forward. Since the atmosphere is the means by which Hg is globally distributed, accurately calibrated measurements are critical to understanding the Hg biogeochemical cycle.
摘要:
汞(Hg)研究人员在理解大气汞方面取得了进展,特别是相对于可以代表大气中汞的2至20%的氧化汞(HgII)。过去10年发展的知识指出了当前测量大气Hg浓度和HgII化合物化学成分的方法存在的挑战。因为这些挑战,大气汞专家开会讨论了当前方法的局限性和克服这些局限性的途径,考虑到正在进行的研究。主要结论包括,目前测量气态氧化和颗粒结合汞的方法有局限性,并且需要开发新的方法来使这些测量更准确。开发用于测量HgII化学的分析方法是具有挑战性的。虽然最终目标是开发用于直接从环境空气中在线检测HgII的超灵敏方法,同时,需要新的表面,在该表面上可以定量地收集HgII并且可以从其可逆地解吸HgII以确定HgII化学。讨论和确定当前的限制,在这里描述,为前进的道路提供基础。由于大气是汞在全球分布的手段,准确校准的测量对于理解汞生物地球化学循环至关重要。