Molecular Composition and Photochemical Reactivity of Size-Fractionated Dissolved Organic Matter.
Molecular Composition and Photochemical Reactivity of Size-Fractionated Dissolved Organic Matter.
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DOI：
10.1021/acs.est.6b05140
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发表时间：
2017-02-21
影响因子：
11.4
通讯作者：
Remucal CK
中科院分区：
文献类型：
--
作者：
Maizel AC;Remucal CK
反应性物种的光化学产生，如三重态溶解有机物（3DOM）和单线态氧（1 O2），有助于水生污染物的降解，并与一系列DOM结构特征，特别是分子量。为了与DOM的分子量，光学性质，和反应性物种的生产，苏瓦尼河（SRFA）和小马湖富里酸（PLFA）的分离物进行分级连续超滤，并得到的馏分进行评价的分子组成和光化学反应性。紫外-可见测量的芳香性增加与分子量在两个富里酸，而PLFA分子量馏分示出的傅里叶变换离子回旋共振质谱法的结构相似。此外，Bray-Curtis相异性分析的公式中确定的分离物和它们的大小馏分显示，SRFA和PLFA具有不同的分子组成。3DOM的量子产率，测量电子和能量转移探针，和1 O2的分子量下降。降低[3DOM]SS与分子量的高分子量馏分，而不是增加3DOM的形成，从升高淬火。这项工作具有影响的光化学沃茨进行自然或工程处理过程，改变DOM分子量，如光氧化和生物降解。
The photochemical production of reactive species, such as triplet dissolved organic matter (3DOM) and singlet oxygen (1O2), contributes to the degradation of aquatic contaminants and is related to an array of DOM structural characteristics, notably molecular weight. In order to relate DOM molecular weight, optical properties, and reactive species production, Suwannee River (SRFA) and Pony Lake fulvic acid (PLFA) isolates are fractionated by sequential ultrafiltration, and the resultant fractions are evaluated in terms of molecular composition and photochemical reactivity. UV– visible measurements of aromaticity increase with molecular weight in both fulvic acids, while PLFA molecular weight fractions are shown to be structurally similar by Fourier-transform ion cyclotron resonance mass spectrometry. In addition, Bray–Curtis dissimilarity analysis of formulas identified in the isolates and their size fractions reveal that SRFA and PLFA have distinct molecular compositions. Quantum yields of 3DOM, measured by electron and energy transfer probes, and 1O2 decreased with molecular weight. Decreasing [3DOM]ss with molecular weight is shown to derive from elevated quenching in high molecular weight fractions, rather than increased 3DOM formation. This work has implications for the photochemistry of waters undergoing natural or engineered treatment processes that alter DOM molecular weight, such as photooxidation and biological degradation.
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影响因子：
2.9
作者：
Canonica, S;Hellrung, B;Wirz, J
通讯作者：
Wirz, J
影响因子：
11.4
作者：
Dong, Mei Mei;Rosario-Ortiz, Fernando L.
通讯作者：
Rosario-Ortiz, Fernando L.
影响因子：
11.4
作者：
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Blough, NV
影响因子：
11.4
作者：
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通讯作者：
GIDDINGS, JC
影响因子：
3
作者：
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通讯作者：
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