Influence of Electrolytes and Humic Acid on Aggregation Behavior of C60 Nanoparticles in Aquatic System

2013 ◽  
Vol 448-453 ◽  
pp. 48-51
Author(s):  
Hua Fang ◽  
Bing Bing Shen ◽  
Yu Xin Sun ◽  
Yuan Wang ◽  
Ji Lai Lu

The aggregation kinetics of C60 nanoparticles have been investigated over a wide range of monovalent and divalent electrolyte concentrations by employing time-resolved dynamic light scattering (DLS). The results showed that the presence of electrolyte made a dramatic decrease in the surface zeta potential and increase in the particle size. The aggregation kinetics of C60 nanoparticles exhibited reaction-limited and diffusion-limited regimes, which was found to be consistent with the classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal stability. The critical coagulation concentration (CCC) values of C60 nanoparticles were estimated as 321mM Na+, 295mM K+, 9.6mM Ca2+and 6.7mM Mg2+, which were far higher than the electrolyte concentrations in natural water. The enhanced C60 stability in the presence of humic acid was attributable to steric repulsion. Therefore C60 nanoparticles can be relatively stable in typical aquatic environments.

2018 ◽  
Vol 20 (34) ◽  
pp. 22218-22227 ◽  
Author(s):  
N. U. M. Howes ◽  
Z. S. Mir ◽  
M. A. Blitz ◽  
S. Hardman ◽  
T. R. Lewis ◽  
...  

Kinetics of CH2OO + SO2 confirmed over a wide range of [SO2]. Acetaldehyde observed as a major product of the reaction of CH3CHOO + SO2.


2015 ◽  
Vol 9 (1) ◽  
pp. 105-111 ◽  
Author(s):  
Xiaoliu Huangfu ◽  
Yaan Wang ◽  
Yongze Liu ◽  
Xixin Lu ◽  
Xiang Zhang ◽  
...  

2010 ◽  
Vol 8 (1) ◽  
pp. 37-41 ◽  
Author(s):  
Narsito Narsito ◽  
Sri Juari Santosa ◽  
Setya Lastuti

The kinetics of photo-reduction of manganese(IV) oxide, MnO2 in aqueous medium, in the presence of humic acid has been investigated, including the possibility for the involvement of such radicals in the reduction. Results showed that in aqueous medium, the efficiency of the photo-reduction of MnO2 producing a soluble ionic Mn(II) was governed strongly by an internal electron transfer within an intermediate of HA-MnO2 anion complex, resulted in the chemical adsorption of humic acid on MnO2 surface. It was observed that under solar radiation and atmosphere containing oxygen, the rate of MnO2 reduction increased considerably, by factors of about 46 and 2 respectively. Moreover, there was evidence that some radicals certainly played a role in the photo-reduction of MnO2, since radical scavenger addition significantly decreased the reduction efficiency of MnO2. In the present of an excess of propanol-2, however, which was expected to remove all OH radicals present, only about 60 % decrease in reduction efficiency were observed, suggesting that radicals other than OH radical are involved in the reduction of MnO2. It was observed further that the presence of iron(III) in MnO2 up to 1 % (w/w) did not alter the reduction efficiency of MnO2.   Keywords: MnO2 kinetics, photo-reduction, aquatic, humic acids


2018 ◽  
Vol 53 (1) ◽  
pp. 146-156 ◽  
Author(s):  
Xiaoliu Huangfu ◽  
Chengxue Ma ◽  
Ruixing Huang ◽  
Qiang He ◽  
Caihong Liu ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document