ABSTRACT
In this study, a UV-curable acrylate epoxy nanocomposite coating has been prepared by incorporation of ZnO-Ag hybrid nanoparticles. For this purpose, firstly ZnO-Ag hybrid nanoparticles were fabricated by a seed-mediated growth method. Then, these ZnO-Ag hybrid nanoparticles (2 wt%) were added into the UV-curable acrylate resin matrices. The photocuring process of nanocomposite was evaluated by various factors, such as the conversion of acrylate double bonds, pendulum hardness and gel fraction. Under the 4.8 s UV-exposure time for full crosslinking, the obtained data indicated that incorporation of ZnO-Ag nanohybrids into the coating matrix changed the crosslinking process of coating significantly. A mechanical teat indicated that the presence of nanohybrids in photocurable coating matrix enhanced its abrasion resistance from 98.7 to 131.6 L per mil (33.3%). The antibacterial test against E. coli over 7 h indicated that E. coli bacteria were killed totally by nanocomposite coating, whereas it was 2.6 × 104 CFU mL-1 for the neat coating without nanoparticles.
ABSTRACT
Large scale supercapacitor electrodes were prepared by 3D-printing directly on a graphite paper substrate from ink solution containing manganese cobalt sulfide/reduced graphene oxide (MCS/rGO) nanocomposites. The MCS/rGO composite solution was synthesized through the dispersion of MCS NPs and rGO in dimethylformamide (DMF) solvent at room temperature. Their morphology and composition were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray diffraction (EDS). The role of rGO on decreasing charge transfer resistance and enhancing ion exchange was discussed. The MCS/rGO electrode exhibits an excellent specific capacitance of 3812.5 F g-1 at 2 A g-1 and it maintains 1780.8 F g-1 at a high current density of 50 A g-1. The cycling stability of the electrodes reveals capacitance retention of over 92% after 22 000 cycles at 50 A g-1.
ABSTRACT
In this manuscript, biological durability, cytotoxicity and MRI image contrast effect of chitosan modified magnetic nanoparticles were investigated. The result of durability study shows that the asprepared sample with average size of about 30 nm had a high stability under pH conditions in range of from 2 to 12 and at salt concentration in range of from 0 to 300 mM. The cytotoxicity testing indicates that the obtained Fe3O4@CS ferrofluid revealed a low cytotoxicity. After 48 h of test on the line of prostate tumor cells of Sarcoma 180, collected IC50 value was 178.5±22 (µg/ml), 7.5 to 27.9 times less cytotoxicity than that of reported ferromagnetic fluids. MRI data shows that the transverse relaxation rate (r2) of the ferrite nanoparticles was 130.32 (mM-1s-1), 2 and 1.44 times larger than that of the commercial products of Sinerem (AMI-227) and Ferumoxytol products, respectively. Invivo test in rabbit shows that the picture of body parts was clearly observed after the injection of the Fe3O4@CS ferrofluid. With these outstanding properties, this magnetic fluid based on the chitosan modified Fe3O4 nanoparticles had great potential for enhancing the image contrast in image diagnosis by MRI magnetic resonance imaging technique.
