A new promising electrochemiluminescence probe based on ruthenium nanobeads/silver nanoparticles/graphene oxide modified electrode for ultra-trace analysis of bisphenol A

Journal of Applied Electrochemistry - In this paper, a novel signal-off electrochemiluminescence sensor based on a ternary nanocomposite of ruthenium nanobeads/silver nanoparticles/graphene oxide...     

Analysis of Non‐Isothermal Viscous Flow Coalescence at Micro Scale

The non‐isothermal coalescence of two spherical bodies caused by capillary‐induced viscous flow was analyzed. Based on this analysis, a new dimensionless number ( K number) was introduced for defining thermal coalescence regimes. Based on the value of this number, coalescence may or may not be affected by thermal effects in different cases. To make this clearer, the conventional coalescence models of Frenkel‐Eshelby and Pokluda were modified by assuming viscosity as a temperature dependent variable. This was conducted by considering the effects of temperature on the viscosity of the involved material through evaluating different expressions including linear and Reynolds and Williams‐Landel‐Ferry (WLF) equations. The results of the modified models for the bridge growth rate show that temperature changes significantly affect the kinetics of coalescence, particularly when the characteristic times of coalescence and heat conduction are in the same order, i.e., moderate K numbers. This analysis is applicable for diverse situations since viscous flow coalescence occurs in various physical and industrial applications of particles or droplets.     

A polyamide thin-film composite membrane modified by Michael addition grafting of hyperbranched poly(amine ester)

In this work polyamide thin-film composite membrane (TFC) surface modified via Michael addition grafting of a hydrophilic hyperbranched poly(amine ester). For this purpose, amine-rich polyamide layer formed by interfacial polymerization on a polyethersulfone support, and then acrylated hyperbranched poly(amine ester) (AC-HBPAE) was used as grafting moiety. The membrane surface was characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), atomic force microscopy (AFM) and water contact angle techniques. Field emission scanning electron microscopy (FE-SEM) was used to evaluate surface and cross-section morphology of samples. Filtration performances and bio-fouling resistance were also studied using a nanofiltration cell. Surface chemical composition and contact angle indicated the successful grafting of acrylated poly(amine ester) to the membrane surface. The results also indicated there is a solid relationship between acrylation percentage of hyperbranched polymer and membrane properties such as fouling resistance. A uniform and hydrophilic surface observed for TFC membrane modified with 5% acrylated hyperbranched poly(amine ester).