Friction Coefficient and Compression Behavior of Particle Reinforced Aluminium Matrix Composites

Metal matrix composites (MMCs) are materials used in a large range of engineering applications. In this paper, the relatively low-cost stir casting is evaluated with the use for Silisyum Carbite (SiC) as reinforcement and Al7075 alloy as matrix to produce MMCs with varied reinforcement from 10% to 18%. The produced composites were examined, and their wear behavior was investigated. The results showed that the mechanical properties of the MMCs decrease with the increase of the mass percentage of reinforcement and compression

Synthesis, characterization, DNA interaction and potential applications of gold nanoparticles functionalized with Acridine Orange fluorophores

Two new water-soluble gold nanoparticles (AO-TEG-Au and AO-PEG-Au NPs) are prepared and characterized. They are stabilized by thioalkylated oligoethylene glycols and functionalized with fluorescent Acridine Orange (AO) derivatives. Despite the different core sizes (11.8 and 3.9 nm respectively) and shell composition, they are both well dispersed and are stable in water, even if some self-aggregation is observed in the case of AO-TEG-Au NPs. However, AO-PEG-Au NPs show much lower emission efficiency with respect to AO-TEG-Au NPs. Spectrophotometric and spectrofluorometric experiments indicate that both types of nanoparticle are able to bind to calf thymus DNA, either by external binding or partial intercalation. Preliminary FACS flow cytometry tests seem to indicate that the AO-TEG-Au nanoparticle is able to cross the cell membrane where it is absorbed by Chinese hamster ovary (CHO) cells at the picomolar concentration level