| 陈子健,黄国城,孟凡刚.化学通报,2018,81(3):236-240. |
| 不同分子尺寸溶解性有机物的光解行为研究 |
| Photochemical degradation of the size-fractionated dissolved organic matter (DOM) |
| 投稿时间：2017-07-05 修订日期：2017-12-07 |
| DOI： |
| 中文关键词: 天然有机物，荧光光谱 ，平行因子，光解，光源 |
| 英文关键词:Natural organic matter (NOM), Fluorescence spectra, Parallel factor (PARAFAC) analysis, Photodegradation, Light source |
| 基金项目:国家自然科学基金项目（No. 51478487） |
|
| 摘要点击次数: 2801 |
| 全文下载次数: 0 |
| 中文摘要: |
| 研究了三个分子量区间（0.45 μm-100 kDa，100 kDa-5 kDa和 <5 kDa）的SRDOM和NRDOM在不同光源下光解行为。DOC和UV254的测试结果表明，光解可以有效地减少所有分子量区间的DOM总量，而且UVC光源的存在可以进一步促进DOM的降解。三维荧光光谱测定结合平行因子分析，识别出3个腐殖质类荧光组分（C1：UVA+UVC，C2：UVA+UVB，C3：UVC）。在光解过程当中，较大分子腐殖质类（>5 kDa）的荧光强度相对较稳定，甚至增强；而小分子腐殖质类（<5 kDa）的荧光组分C1和C2具有显著地光解行为，UVC的存在可以促进两种荧光组分的光解。所有分子量区间的C3组分都发生了光生成现象。 |
| 英文摘要: |
| In this study, the photodegradation of the size-fractionated dissolved organic matter (0.45μm-100kDa, 100 kDa-5 kDa, <5 kDa) at different light sources was investigated. Measurements of dissolved organic carbon (DOC) and UV254 absorbance showed that sunlight exposure led to the decrease of DOM in all the three fractions over a 6-days period of 6 h/d irradiation, and the presence of UVC light in natural sunlight can speedup DOM elimination. The parallel factor (PARAFAC) analysis of fluorescence excitation emission matrices (EEM) revealed the presence of three humic-like components (C1: UVA+UVC; C2: UVA+UVB; C3: UVC) in the DOM samples. In addition, the fluorescent components in large-size DOM fractions (>5 kDa) were not sensitive to sunlight exposure, and some of which increased upon sunlight exposure. However, the C1 and C2 in the small-size DOM fractions (<5 kDa) were much more susceptible to sunlight exposure, both of which decreased significantly after the 6-days incubation. But, the C3 components in all DOM fractions were found to be photo-produced. Also, the presence of the UVC light in sunlight can somewhat speedup the elimination of C1 and C2 or decrease the generation of C3. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |