Chow Judith C, Yu Jian Zhen, Watson John G, Ho Steven Sai Hang, Bohannan Theresa L, Hays Michael D, Fung Kochy K
Desert Research Institute, Reno, Nevada 89512, USA.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2007 Sep;42(11):1521-41. doi: 10.1080/10934520701513365.
Thermal methods of various forms have been used to quantify carbonaceous materials. Thermal/optical carbon analysis provides measurements of organic and elemental carbon concentrations as well as fractions evolving at specific temperatures in ambient and source aerosols. Detection of thermally desorbed organic compounds with thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) identifies and quantifies over 100 individual organic compounds in particulate matter (PM) samples. The resulting mass spectra contain information that is consistent among, but different between, source emissions even in the absence of association with specific organic compounds. TD-GC/MS is a demonstrated alternative to solvent extraction for many organic compounds and can be applied to samples from existing networks. It is amenable to field-deployable instruments capable of measuring organic aerosol composition in near real-time. In this review, thermal stability of organic compounds is related to chemical structures, providing a basis for understanding thermochemical properties of carbonaceous aerosols. Recent advances in thermal methods applied to determine aerosol chemical compositions are summarized and their potential for uncovering aerosol chemistry are evaluated. Current limitations and future research needs of the thermal methods are included.
各种形式的热方法已被用于量化含碳物质。热/光碳分析可测量环境气溶胶和源气溶胶中有机碳和元素碳的浓度，以及在特定温度下释放的组分。利用热脱附-气相色谱/质谱联用仪（TD-GC/MS）检测热脱附的有机化合物，可识别并定量颗粒物（PM）样品中的100多种单个有机化合物。即使在未与特定有机化合物关联的情况下，所得质谱图包含的信息在源排放之间也是一致的，但彼此不同。对于许多有机化合物而言，TD-GC/MS已被证明是溶剂萃取的替代方法，并且可应用于现有监测网络采集的样品。它适用于能够近实时测量有机气溶胶成分的现场可部署仪器。在本综述中，有机化合物的热稳定性与化学结构相关，为理解含碳气溶胶的热化学性质提供了基础。总结了应用于确定气溶胶化学成分的热方法的最新进展，并评估了它们在揭示气溶胶化学方面的潜力。还包括热方法目前的局限性和未来的研究需求。
