...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Light-Source-Dependent Effects of Main Water Constituents on Photodegradation of Phenicol Antibiotics: Mechanism and Kinetics
【24h】

Light-Source-Dependent Effects of Main Water Constituents on Photodegradation of Phenicol Antibiotics: Mechanism and Kinetics

机译：主要水成分对苯酚类抗生素光降解的光源依赖性作用：机理和动力学

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Thiamphenicol and florfenicol are two phenicol antibiotics commonly used in aquaculture. Photodegradation experiments on these phenicols were performed in aqueous solutions under irradiation of different light sources. We found under UV-vis irradiation (λ > 200 nm) they photodegraded the fastest in seawater, followed by pure water and freshwater, whereas under solar or simulated sunlight (λ > 290 nm), they photodegraded in freshwater only. The effects of Cl~- (the dominant seawater constituent), humic acids (HA, main constituents in freshwater) and other water constituents on the photodegradation of the antibiotics as a function of different light sources were studied so as to interpret the light-source-dependent effects of different waters. Under UV-vis irradiation, Cl~- was found to promote singlet oxygen (~1O_2) formation and accelerated the photodegradation of phenicols, whereas the phenicols did not photolyze under simulated solar irradiation, irrespective of Cl~-. In contrast, the presence of HA inhibited phenicol photolysis under UV-vis irradiation through competitive photoabsorption, but HA photosensitized degradation under simulated solar irradiation. Under UV-vis irradiation, the wavelength-averaged (200-290 nm) quantum yields for thiamphenicol and florfenicol in pure water were 0.022 ± 0.001 and 0.029 ± 0.001, respectively. Their solar photolytic half-lives in freshwater were 186 ± 17 h and 99 ± 16 h, respectively. UV-vis photodegradation intermediates were identified by HPLC-MS/MS, and degradation pathways were proposed. These involve photoinduced hydrolysis, dechlorination, self-sensitized photo-oxidation process via ~1O_2, and chlorination. These results are of importance toward the goal of assessing the persistence of phenicols in wastewater treatment and the environment.
机译：甲砜霉素和氟苯尼考是水产养殖中常用的两种苯酚抗生素。在水溶液中，在不同光源的照射下，对这些酚进行了光降解实验。我们发现，在紫外线可见光照射下（λ> 200 nm），它们在海水中的光降解最快，其次是纯水和淡水，而在日光或模拟阳光下（λ> 290 nm），它们仅在淡水中被光降解。研究了Cl〜-（主要的海水成分），腐殖酸（HA，淡水中的主要成分）和其他水成分对抗生素光降解的影响，这些作用是不同光源的函数，以解释光源水域的依赖效应。在紫外可见光照射下，Cl〜-被发现促进单线态氧（〜1O_2）的形成并促进苯酚的光降解，而苯酚在模拟的太阳辐射下不会光解，而与Cl〜-无关。相反，HA的存在通过竞争性光吸收抑制了紫外可见辐射下苯酚的光解，但HA在模拟太阳辐射下光敏降解。在紫外可见光照射下，纯水中的甲砜霉素和氟苯尼考的​​波长平均（200-290 nm）量子产率分别为0.022±0.001和0.029±0.001。它们在淡水中的太阳光解半衰期分别为186±17 h和99±16 h。通过HPLC-MS / MS鉴定了紫外可见光降解中间体，并提出了降解途径。这些包括光致水解，脱氯，通过〜1O_2的自敏化光氧化过程以及氯化。这些结果对于评估酚类在废水处理和环境中的持久性这一目标具有重要意义。

著录项

  • 来源
    《Environmental Science & Technology》 |2009年第9期|3101-3107|共7页
  • 作者

    LINKE GE; JINGWEN CHEN; XIANLIANG QIAO; JING LIN; XIYUN CAI;

  • 作者单位

    Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Department of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, P. R. China;

    Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Department of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, P. R. China;

    Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Department of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, P. R. China;

    Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Department of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, P. R. China;

    Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Department of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, P. R. China;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号