JOURNAL OF HAZARDOUS MATERIALS
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2025
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IF 11.3
Dianji Ding,Jiao Fei,Yong Yao,Yanji Jiang,Huimin Sun,Xianqiang Yin
Quantum dots (QDs), emerging semiconductor nanomaterials, have been detected in various environmental media and can adsorb co-existing contaminants (e.g., Pb 2+ ). Surface modifications aimed at enhancing the performance of QDs can significantly affect their physicochemical properties, but their effects on QDs environmental behavior remain unclear. Herein, we investigated the adsorption and co-transport behaviors of aminated (NQD), hydroxylated (OQD), and carboxylated cadmium sulfide QDs (CQD) with Pb 2+ via batch adsorption and quartz sand column experiments. The influence of ionic strength (IS) and cation valence on the co-transport of QDs and Pb 2+ was examined. Our experimental findings revealed that Pb 2+ inhibited the mobility of OQD and CQD but enhanced the transport of NQD due to the surface complexation and cation bridging effects. This promoting effect was weakened with increasing IS and cation valence, indicating the involvement of non-Derjaguin-Landau-Verwey-Overbeek forces. Furthermore, OQD and CQD with high mobility and strong affinity to Pb 2+ effectively promoted the transport of Pb 2+ , with CQD exhibiting a more pronounced effect than OQD. Conversely, NQD reduced Pb 2+ efflux due to their lower mobility and stronger adsorption to Pb 2+ . These results provide valuable insights into the role of surface modifications on QDs and their interactions with co-existing contaminants in subsurface environments.
研究领域:
环境科学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
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2020
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IF 6.793
Mengjie Wang,Yumeng Song,Haojing Zhang,Taotao Lu,Weifeng Chen,Wenwen Li,Wei Qi,Zhichong Qi
In this study, batch and column tests were performed to investigate the co-transport of graphene oxide (GO) nanoparticles and tetracycline in saturated porous media under various solution chemistry conditions. Research indicated that GO and tetracycline had mutual promotion effect on their transport in the porous media under all the tested conditions, which was ascribed to the high adsorption capacity of tetracycline onto GO and the increased electrostatic repulsion as well as their competition for deposition sites on sand surfaces. Interestingly, the mutually promoting function of GO and tetracycline under acidic conditions was greater than that under alkaline conditions, the dominant mechanism was that the increased solution pH decreased the sorption of tetracycline onto GO and weakened the deposition site competition. Furthermore, the mutually promoting effect of GO and tetracycline was Na + or Ca 2+ concentration-dependent. Specially, increased Ca 2+ concentration weakened the promoting effect of GO on tetracycline transport but magnified the promoting effect of tetracycline on GO transport. This is because higher Ca 2+ concentration could cause a decrease in the adsorption of tetracycline on GO and facilitate more tetracycline molecules to occupy the deposition sites on sand surfaces. Additionally, sodium dodecyl sulfate had enhancement effect on co-transport of GO and tetracycline. Findings from this study clearly indicated that antibiotics and carbon based nanomaterials may transport together under various solution chemistry conditions, and consequently affect their fates in aquatic environments.
研究领域:
环境科学
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纳米材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2023
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IF 13.6
Xiaoying Zhang,Fangfei Cai,Funing Ma,Paul Reimus,Linlin Qi,Di Lu,Mohamad Reza Soltanian,Zhenxue Dai
Colloids play a crucial role in influencing the mobility of radionuclides in high-level radioactive waste repositories. However, the co-transport behavior of radionuclides and colloids in geological media remains insufficiently understood. This study investigated the transport of Strontium (Sr) in four types of granite minerals (quartz, biotite , K-feldspar, and plagioclase) in the presence and absence of Na-bentonite colloids (Na-BC) using column experiments. Employing a stepwise modeling strategy, this study first determined the basic flow and transport parameters through breakthrough curve analysis of the conservative tracer (Br). Then, the experimental data of Sr in the colloid-free Sr transport experiments and Na-BC in the Sr-colloid co-transport experiments were quantitatively explained using a two-site sorption model and a two kinetic sites model, respectively. Finally, the co-transport behavior of Sr and Na-BC was fitted using the colloid-facilitated solute transport model. The stepwise modeling allowed quantification of the kinetics of Sr sorption onto mobile and immobile Na-BC and highlighted the role of straining in Na-BC retention. In the absence of Na-BC, Sr transport experienced the greatest retardation in biotite, followed by plagioclase, K-feldspar, and quartz, respectively, which positively correlated with the specific surface area of the minerals. Moreover, Na-BC enhanced Sr transport with the same retardation order in all tested minerals, with recovery rate increments of 68.61%, 19.21%, 6.67%, and 4.33%, respectively. The transport of Sr in K-feldspar was found to be less affected by Na-BC compared to the other tested minerals, likely due to the strong cation exchange capacity of K + among the cation components of minerals, making hydrated K + more likely to exchange with Sr 2+ on K-feldspar surfaces. These findings hold significant implications for assessing the risks associated with the transport of radionuclides in deep geological repositories.
研究领域:
环境科学
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放射性废物管理
✓ 已验证
DOI
高影响因子
WATER RESEARCH
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2022
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IF 13.4
Mengmeng Wu,Erping Bi,Binghua Li
Soil colloids can affect the cotransport of nanoparticles and pollutants. In this study, the influencing mechanisms of organic fulvic acid (FA) and inorganic montmorillonite colloid (MONT) on the cotransport of nHAP and Cd(II) were investigated. Column experiments combined with Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, attachment efficiency calculation and two-site kinetic retention model were applied to study the mechanisms. Results showed that the co-existence of FA or MONT made the transport of nHAP improved by 58–75% and 33–59%, respectively. Both of them could improve the stability of nHAP particles and enhance electrostatic repulsion between nHAP particles and sand. Retention of nHAP in the sand was mainly caused by secondary energy minimum and physical straining. The co-existence of FA or MONT changed the amount of adsorbed species of Cd(II) and decreased the retardation effect of nHAP on Cd(II) transport. With increasing FA concentration, soluble FA·Cd and suspended nHAP·FA·Cd complexes in the system increased. Transport of soluble Cd(II) and total Cd(II) were strengthened due to the concentration effect of FA and the improved stability of nHAP particles. With increasing MONT concentration, the amount of soluble Cd(II) decreased, but that of colloidal Cd(II) (nHAP·Cd and MONT·Cd) increased. Due to the stronger effect of colloidal Cd(II) change than that of the soluble Cd(II) change, the transport of total Cd(II) was improved by 34–57%. The findings of this study can help to understand the fate of nanoparticles and Cd(II) in natural water and soil.
研究领域:
环境科学
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土壤化学
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胶体科学
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水质
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）