Dosimetric analysis of graphitic carbon nitride quantum dots exposed to a gamma radiation for a low-dose applications.

In this study, graphitic carbon nitride quantum dots (g-C3N4QDs) were synthesized using different solvents, characterized, and then exposed to a gamma-ray source (137Cs) at irradiation doses of 0.1, 1.48, 2.05 and 3.25 Gy. The intensities of the emission bands progressively were attenuated as the received dose of gamma radiation increased. The changes were quantified with the help of a non-linear fit model. The material showed promising use as a dosimeter for low-dose radiation applications.

Magnetic nanofibrous materials based on CMC/PVA polymeric blends.

In this paper, the synthesis of magnetic nanofibrous materials with a soft ferromagnetic response based on magnetite nanoparticles (SMON) loaded to aqueous carboxymethyl-cellulose (CMC)/polyvinyl-alcohol (PVA) polymeric blends is reported. The nanofibrous materials were obtained from the electrospinning of SMON-CMC/PVA blends with different SMON content, applying a constant tension of 15 kV. The synthesized samples were analyzed by transmission electron microscopy, scanning electron microscopy, attenuated total reflectance Fourier transform infrared, Raman and X-Ray photoelectron spectroscopy, as well as static magnetic measuring. Our experimental findings indicate that nanofibers' diameter decreases as SMON content in the electrospun polymeric blends is increased, since these magnetic nanoparticles diminish the interactions between PVA and CMC molecules, which improves their spinnability. Moreover, the spatial distribution of SMON in the fibers provides to the synthesized nanofibrous materials a novel soft ferromagnetic response at room temperature. This phenomenon is attributed to the formation of nanoparticles' aggregates that are discretely distributed in the nanofibers.

Ti, Ni and TiNi nanoparticles physically synthesized by Ar+ beam milling.

When the size of a particle decreases around 100 nm or less, there is a change in properties from those shown in the bulk material. In this work approximately 3 nm nanoparticles of Ni, Ti and TiNi bimetallic are produced using physical vapor deposition (PVD). Nanoparticles are characterized by High Resolution Transmission Electron Microscopy (HRTEM), High Angle Annular Dark Field (HAADF), Electron Diffraction (ED). The results show that all nanoparticles maintain the same crystal structure of bulk material but a change in their lattice parameter is produced.

Three-layer core/shell structure in Au-Pd bimetallic nanoparticles.

This paper describes the internal structure of Au-Pd nanoparticles exhibiting newly discovered three-layer core/shell morphology, which is composed of an evenly alloyed inner core, an Au-rich intermediate layer, and a Pd-rich outer shell. By exploitation of spatially resolved imaging and spectroscopic and diffraction modes of transmission electron microscopy (TEM), insights were gained on the composition of each one of the observed three layers, indicating a significant extent of intimate alloy among the monometallic elements.