Nanoporous silicon oxide templates formed by swift heavy ion tracks technology have been investigated. The influence of the heavy ion characteristics, such as type of ion, energy, stopping power and irradiation fluence on the pore properties of the silicon oxide templates, has been studied. Furthermore, the process of pore formation by chemical etching with hydrofluoric acid has been thoroughly investigated by assessing the effect of etchant concentration and etching time. The outcome of this investigation enables us to have precise control over the resulting geometry of nanopores arrays. As a result, guidelines for the creation of a-SiO2/Si templates with tunable parameters and general recommendations for their further application are presented.
Modern electronic systems and equipment used in aerospace and nuclear technology, as well as many scientific and medical devices, are used under the influence of a wide range of ionizing radiation (electrons, protons, heavy charged particles etc.). Protons or heavy charged particles exposure can lead to failures in the operation of spacecrafts electronic devices, which is associated with the radiation effects occurrence in an integrated circuits. One of the most effective ways to solve this problem is protection by radiation shields. Linear and mass paths of protons and Ar+ ions in Al, Al2O3, Bi, and W77, 7Cu22, 3 composite shields were calculated using a SRIM software package. It is shown that the protection efficiency against high-energy ions by materials with large atomic charge values (Z) is higher from the position of linear ranges of particles, and lower from the position of mass ranges than materials with low Z values. The dependence of the threshold energy on the serial number of particles for Al, Bi and W77, 7Cu22, 3 composite shields is determined. The effect of the sequence in the arrangement and layer thicknesses in the Bi/Al/Al2O3 multilayered structures on the protection efficiency against high-energy ions was studied.
Due to the Ni nanotubes' shape anisotropy, low specific density, large specific surface, and uniform magnetic field, they have been offered as carriers for targeted delivery of drug or protein and the process of their formation from synthesis stage to the stage of surface modification and protein attaching has been demonstrated. Some steps to hasten their biomedical application have been applied. First, to have full control over the carrier dimensions and structure parameters, electrodeposition method in pores of polyethylene terephthalate template has been applied. Second, to understand the scope of Ni nanostructures application, their degradation in media with different acidity has been studied. Third, to improve the biocompatibility and to make payloads attachment possible, nanotubes surface modification with organosilicon compound has been carried out. At last, the scheme of protein attaching to the nanostructure surface has been developed and the binding process was demonstrated as an example of the bovine serum albumin.
Bi nanocrystalline films were formed from perchlorate electrolyte (PE) on Cu substrate via electrochemical deposition with different duration and current densities. The microstructural, morphological properties, and elemental composition were studied using scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray microanalysis (EDX). The optimal range of current densities for Bi electrodeposition in PE using polarization measurements was demonstrated. For the first time, it was shown and explained why, with a deposition duration of 1 s, co-deposition of Pb and Bi occurs. The correlation between synthesis conditions and chemical composition and microstructure for Bi films was discussed. The analysis of the microstructure evolution revealed the changing mechanism of the films’ growth from pillar-like (for Pb-rich phase) to layered granular form (for Bi) with deposition duration rising. This abnormal behavior is explained by the appearance of a strong Bi growth texture and coalescence effects. The investigations of porosity showed that Bi films have a closely-packed microstructure. The main stages and the growth mechanism of Bi films in the galvanostatic regime in PE with a deposition duration of 1–30 s are proposed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.