芳香族碳被认为是最活跃的分子部分之一 在水氯化过程中生成三卤甲烷（THM）。研究表明 254nm处的紫外吸收率（UVA254）很好地代表了样品中的芳香族含量 溶解有机碳（DOC）。因此，特定的UVA254（SUVA254）相当于 碳标准化UVA254已被广泛用于测量芳香族有机化合物 碳含量和三卤甲烷形成潜力。然而，最近的研究表明 质疑使用SUVA254预测THM形成的可靠性，因为硝酸盐， 氯化作用下有机碳的溴化和非反应性共轭双键 还可以在254 nm处吸收UVA。作者假设SUVA254中的差异 氯化前后（ΔSUVA254）应与 THM if SUVA254测量DOC中THM反应位点的数量。作者 检测了萨克拉门托-圣华金三角洲农业土壤中的DOC 来自萨克拉门托-圣华金流域的35个河流遗址。关系 在SUVA254、ΔUVA254/DOC和ΔSUVA254与特定THM形成之间 对其潜力进行了评估。结果表明，相关系数 ΔUVA254/DOC-STHMFP和ΔSUVA254-STHMFP略优于SUVA- STHMFP。此外，在272 nm的UVA方面，所有这些参数都提供了更好的效果 相关性比254 nm处的UVA强。包括13个参考文献、表格、图表。

Aromatic carbon is considered one of the most reactive molecular moieties with respect to trihalomethanes (THM) formation during water chlorination. Studies have shown that ultraviolet absorbance at 254 nm (UVA254) is a good proxy for aromatic content in dissolved organic carbon (DOC). Thus, specific UVA254 (SUVA254), which is equal to carbon normalized UVA254, has been widely used as a measure for aromatic organic carbon content and trihalomethane formation potential. However, recent studies have questioned the reliability of using SUVA254 to predict THM formation because nitrate, bromide and non-reactive conjugated double bonds of organic carbon under chlorination also absorb UVA at 254 nm. The authors hypothesize that the difference in SUVA254 before and after chlorination (ΔSUVA254) should be proportional to the formation of THM if SUVA254 measures the amount of THM reactive sites in DOC. The authors examined DOC originating from agricultural soils in the Sacramento-San Joaquin Delta and from 35 river sites in the Sacramento-San Joaquin watershed. The relationships between SUVA254, ΔUVA254/DOC and ΔSUVA254 versus specific THM formation potential were evaluated. Results indicated that the correlation coefficients of ΔUVA254/DOC-STHMFP and ΔSUVA254-STHMFP are slightly better than SUVA- STHMFP. Also, all these parameters in terms of UVA at 272 nm provide slightly better correlation than UVA at 254 nm. Includes 13 references, table, figures.