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| Abstract: |
| At present, a growing number of consumer products contain engineered nanoparticle TiO2 (nano-TiO2), which has resulted in the consequences of nano-TiO2 entering the aquatic environment directly or indirectly at some stage. The fate of nano-TiO2 in the aquatic environment has become the key factor which affects its safety application and nanoecotoxicology. This paper aims to investigate how the dissolved organic matters (DOM), especially the molecular weight fractions in the aquatic environment, affect the aggregation, stability, and fate of nano-TiO2, and the interaction mechanism of DOM and nano-TiO2. Results of dynamic light scattering (DLS) showed that the molecular weight of DOM molecules caused different aggregation rates of nano-TiO2 in aqueous solution. Fourier Transform infrared spectroscopy (FTIR) results indicated the molecular structure is characteristics of DOM fractions and the mechanisms of bonds formation between DOM and nano-TiO2. Results of three-dimensional excitation-emission matrices (3D-EEM) confirmed the FTIR results and implied the increase of the stability of the π-π conjugated system in the presence of DOM. In addition, low molecular weight of DOM fractions appeared to show more affinity with nano-TiO2 than high molecular weight fractions. |
| Key words: titanium dioxide nanoparticles dissolved organic matter different molecular weight organics |
| DOI：10.11916/j.issn.1005-9113.19002 |
| Clc Number:X592 |
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| Descriptions in Chinese: |
| 不同分子量的溶解性有机物对水中纳米二氧化钛的影响机理 杨晓南1，刘冬梅1，崔福义2 （1. 哈尔滨工业大学 环境学院，哈尔滨 150090； 2. 重庆大学 城市建设与环境工程学院，重庆 400044） 摘要：目前，日益增长的消费产品中含有纳米二氧化钛，这将会导致纳米二氧化钛直接或间接地排放到水环境中。纳米二氧化钛在水中的迁移转化则是影响其安全应用及纳米生态毒性的重要因素。本文通过考察纳米二氧化钛与水中不同分子量天然有机物的稳定性及聚集过程。动态光散射数据显示不同分子量的有机物与纳米二氧化钛相互作用显示不同的聚集率。三维荧光光谱和傅里叶红外光谱结果显示溶解性有机物与纳米二氧化钛相互作用机制主要为π-π作用机制，而且，低分子量的溶解性有机物比高分子量的溶解性有机物结合力更强。 关键词：纳米二氧化钛，溶解性有机物，不同分子量的有机物 |
