An Insight into the Defects-Driven Plasticity in Ductile Cast Irons.

The microstructure and tensile behavior of two heavy section castings that had chemical compositions typical of GJS400 were investigated. Conventional metallography, fractography, and micro-Computer Tomography (μ-CT) were employed, enabling the quantification of the volume fractions of eutectic cells with degenerated Chunky Graphite (CHG), which was identified as the major defect in the castings. The Voce equation approach was exploited to evaluate the tensile behaviors of the defective castings for integrity assessment.

Electron Beam Welding of IN792 DS: Effects of Pass Speed and PWHT on Microstructure and Hardness.

Electron Beam (EB) welding has been used to realize seams on 2 mm-thick plates of directionally solidified (DS) IN792 superalloy. The first part of this work evidenced the importance of pre-heating the workpiece to avoid the formation of long cracks in the seam. The comparison of different pre-heating temperatures (PHT) and pass speeds () allowed the identification of optimal process parameters, namely PHT = 300 °C and = 2.

Bactericidal performance of nanostructured surfaces by fluorocarbon plasma.

This study presents the characterization and antibacterial activity of nanostructured Si by plasma treatment method using a tetrafluoromethane (CF) and hydrogen (H) mixture. Nanostructured-Si is a synthetic nanomaterial that contains high aspect ratio nanoprotrusions on its surface, produced through a reactive-ion etching process. We have shown that the nanoprotrusions on the surfaces produce a mechanical bactericidal effect.

Photo-Physical Behaviour of CdSe Nanocrystals/Bis(dithiocarbamate) Linker Multilayered Hybrid Systems.

Multilayered films composed by CdSe Nanocrystals (NCs) interlinked by ethylene-1,2-bis(dithiocarbamate) or adipate anions were prepared on ITO glass via layer-by-layer alternation. The films were analyzed by UV-vis, TEM, Photoluminescence (PL) emission and Pump-Probe spectroscopy. While the PL emission of the two samples present no differences, femtosecond Pump-probe experiments reveal an higher charge generation efficiency in bis(dithiocarbamate) based films than in dicarboxylate ones.

Enhanced short-term plasmid transfection of filtration surgery tissues.

Purpose: To quantify and localize plasmid transfection of filtration surgery tissues using two delivery techniques.

Methods: Full-thickness filtering procedures were performed on eyes of New Zealand albino rabbits. In 10 eyes, naked plasmid DNA in saline was either injected beneath Tenon's capsule at the filtration site or absorbed into a collagen shield that was then placed external to the sclerostomy and under the Tenon's capsule.