中文摘要：

N-nitrosodimethylamine (NDMA ) 是面对基于胺的先锋在水消毒期间被形成的一个新兴的消毒副产品。作为一个种基于胺的药品， Ranitidine 在 chloramination 期间与高 NDMA 臼齿的变换作为 NDMA 先锋被识别了。这研究在 ranitidine 的 ozonation 期间集中了于 NDMA 形成的描述。运作的变量的影响(臭氧剂量， pH 价值) 并且 NDMA 产生上的水矩阵以及 ranitidine 降级被评估。结果与臭氧显示 ranitidine 的高反应。Dimethylamine (直接存储器存取) 和 NDMA 由于 ranitidine 氧化被产生。高 pH 价值引起了更多的 NDMA 累积。NDMA 形成在酸条件下面被禁止(pH ?? 5 ) 主要由于胺的 protonation。象 HCO ₃ 和腐殖的酸那样的水矩阵影响了 NDMA 产生由于哦清除。与相比哦，臭氧分子统治了直接存储器存取和 NDMA 的生产。然而，哦是在 NDMA 的一个关键因素降级。ranitidine 的转变产品用煤气的层析团 spectrometry 在 ozonation 期间被识别。在这些产品，就直接存储器存取和 N 之中， N-dimethylformamide 能在分子的结构由于 DMA 组贡献 NDMA 形成。从 ranitidine ozonation 的 NDMA 形成小径也被建议。

英文摘要：

N-nitrosodimethylamine（NDMA） is an emerging disinfection by-product which is formed during water disinfection in the presence of amine-based precursors. Ranitidine, as one kind of amine-based pharmaceuticals, has been identified as NDMA precursor with high NDMA molar conversion during chloramination. This study focused on the characterization of NDMA formation during ozonation of ranitidine. Influences of operational variables（ozone dose, pH value） and water matrix on NDMA generation as well as ranitidine degradation were evaluated. The results indicate high reactivity of ranitidine with ozone.Dimethylamine（DMA） and NDMA were generated due to ranitidine oxidation. High pH value caused more NDMA accumulation. NDMA formation was inhibited under acid conditions（pH ≤ 5） mainly due to the protonation of amines. Water matrix such as HCO-3and humic acid impacted NDMA generation due to UOH scavenging. Compared with UOH,ozone molecules dominated the productions of DMA and NDMA. However, UOH was a critical factor in NDMA degradation. Transformation products of ranitidine during ozonation were identified using gas chromatography–mass spectrometry. Among these products, just DMA and N,N-dimethylformamide could contribute to NDMA formation due to the DMA group in the molecular structures. The NDMA formation pathway from ranitidine ozonation was also proposed.