Dissolved black carbon (DBC) is an important component of dissolved organic matter pool; however, its photochemical properties are not fully understood. In this study, we determined the excited triplet-state quantum yields of DBC (3DBC*) and 1O2 quantum yields (Φ1O2) of six diverse DBCs using sorbic alcohol, 2,4,6-trimethylphenol (TMP), and furfuryl alcohol and compared the results with quantum yields of reference natural organic matters (NOMs). The average Φ1O2 of six DBCs (4.2 ± 1.5%) was greater than that of terrestrial NOM (2.4 ± 0.3%) and comparable to autochthonous NOM (5.3 ± 0.2%). Using TMP as a probe for oxidizing triplets, DBC presented significantly higher apparent quantum yield coefficients for degrading TMP (fTMP) than the reference NOM, reflecting that the fTMP values of low-energy 3DBC* were approximately 12-fold greater than those of low-energy 3NOM*. The differences in the fTMP and Φ1O2 trends among the DBCs indicated that the 3DBC* responsible for these reactions may be from different sources. In addition, DBC was much more effective than NOM, on a carbon-normalized basis, during photodegradation of pharmaceutically active compounds. This result confirms that the presence of DBC can accelerate the photodegradation of contaminants that are susceptible to one-electron oxidation by triplets.

中文翻译：

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溶解黑碳的三重态光化学及其对活性氧光化学形成的影响。

溶解黑碳（DBC）是溶解有机物库的重要组成部分。然而，其光化学性质尚未完全被理解。在这项研究中，我们确定了使用山梨醇，2,4,6-三甲基苯酚（TMP）和糠醇对六种不同DBC的DBC的激发三重态量子产率（3DBC *）和1O2量子产率（Φ1O2）进行比较。参考天然有机物（NOM）的量子产率得到的结果。六个DBC的平均Φ1O2（4.2±1.5％）大于陆地NOM（2.4±0.3％），与本地NOM（5.3±0.2％）相当。使用TMP作为氧化三联体的探针，DBC在降解TMP（fTMP）方面表现出比参考NOM高得多的表观量子产率系数，反映出低能3DBC *的fTMP值大约是低能3NOM *的fTMP值的12倍。DBC之间fTMP和Φ1O2趋势的差异表明，负责这些反应的3DBC *可能来自不同的来源。另外，在药物活性化合物的光降解过程中，以碳归一化为基础，DBC比NOM更有效。该结果证实，DBC的存在可以促进容易受到三重态单电子氧化的污染物的光降解。在药物活性化合物的光降解过程中。该结果证实，DBC的存在可以促进容易受到三重态单电子氧化的污染物的光降解。在药物活性化合物的光降解过程中。该结果证实，DBC的存在可以促进容易受到三重态单电子氧化的污染物的光降解。