![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
The free radical concentration in the atmosphere is typically low, short-lived, and highly reactive, often acting as a key intermediate in atmospheric oxidation processes. Understanding these radicals is crucial for unraveling the oxidative properties of the atmosphere and identifying the sources of pollution. One of the major challenges in this field is the comprehensive detection of free radical reaction species—including reactants, transient intermediates, and products—and the accurate identification of isomers with similar structures.
Recently, a research team led by Professor An Guangshang and Zhang Weijun has made significant progress in developing vacuum ultraviolet (VUV) photoionization mass spectrometry for studying atmospheric free radical reactions. Their work, titled "A vacuum ultraviolet photoionization time-of-flight mass spectrometer with high sensitivity for study of gas phase radical reaction in flow tube," was recently published in the *International Journal of Chemical Kinetics* (DOI: 10.1002/kin.21241).
The team, including researcher Tang Xiaofeng, enhanced VUV photoionization mass spectrometry through an innovative ion source design. By combining this with a self-developed high-resolution, high-sensitivity small-reflection time-of-flight mass spectrometer, they achieved highly sensitive detection of free radicals in flow reactor systems, reaching international standards in performance. Using synchrotron radiation as an ionization source, they successfully conducted full-scale detection of radical reaction species and efficiently distinguished isomers using photoionization efficiency spectra.
The journal's editors and reviewers praised the study, noting that "highly sensitive free radical detection is very beneficial for the study of reaction kinetics in the atmosphere and combustion chemistry." They also highlighted the importance of lowering the detection limit to around 0.8 parts per billion, which is essential for detecting low-density species like radicals in chemical kinetics experiments related to atmospheric and combustion processes. The review concluded that "this is a very good start, and we expect more interesting work from the authors in the future."
This research was supported by the National Key Research and Development Program, the National Natural Science Foundation, and the Chinese Academy of Sciences' International Cooperation Key Project. The development of this advanced analytical technique represents a significant step forward in understanding complex atmospheric chemical processes.
vacuum assisted injection molding,gas assisted mould & moulding planes,gas assisted mould & moulding kit,gas assisted injection molded products
Global Injection Molds Co., LTD , https://www.globalinjectionmolds.com