Silver nanoparticles (AgNPs) have been assessed to have a high exposure risk for humans and aquatic organisms. Toxicity varies considerably between different types of AgNPs. This study aimed to investigate the toxic effects of AgNPs with different particle sizes (40 and 110 nm) and different surface coatings (sodium citrate and polyvinylpyrrolidone, PVP) on Daphnia magna and their mechanisms of action. The results revealed that the citrate-coated AgNPs were more toxic than PVP-coated AgNPs and that the 40 nm AgNPs were more toxic than the 110 nm AgNPs. Transcriptome analysis further revealed that the toxic effects of AgNPs on D. magna were related to the mechanisms of ion binding and several metabolic pathways, such as the “RNA polymerase” pathway and the “protein digestion and absorption” pathway. Moreover, the principal component analysis (PAC) results found that surface coating was the major factor that determines the toxicities compared to particle size. These results could help us better understand t...

Toxic Effects and Molecular Mechanism of Different Types of Silver Nanoparticles to the Aquatic Crustacean Daphnia magna

Extensive usage of the structured packings in various industrial applications has led to comprehensive investigations of their properties and performance. Among various methods of modeling, computa...

CFD simulation of the structured packings: A review

Direct numerical simulation of interphase heat and mass transfer in multicomponent vapour–liquid flows

The reaction environment in a filter-press laboratory reactor: the FM01-LC flow cell

CFD Simulation of Flow and Mass Transfer in Structured Packing Distillation Columns

The liquid phase residence time distribution (RTD) for gas–liquid countercurrent flow in a packed column with a novel internal was measured by conductivity measurements and an air–water system. The RTD of a liquid tracer is well represented by the ADM and PDE models. At lower gas flow rates, the Peclet number of the liquid in the packed column with the internal is lower than that without the internal; at higher gas flow rates, it is vice versa, especially with an internal with a higher volume fraction. The distribution of the liquid RTD can be improved by using suitable geometric parameters of the internal to give a larger volume fraction and a lower stage height.

Yanhui Yuan

Papers

Liquid phase residence time distribution for a two-phase countercurrent flow in a packed column with a novel internal

Mass transfer coefficient for two-phase countercurrent flow in a packed column with a novel internal

Experimental and CFD analysis of two-phase cross/countercurrent flow in the packed column with a novel internal

Pressure drop for two phase counter-current flow in a packed column with a novel internal