Journal of Nanosciences: Pesquisa Atual

Nickel and graphite was potentiostatically co-deposited using a composite nickel-graphite composite counter electrode (CCE) with tunable-friability. This was done to achieve steady introduction of graphite into the electrolyte without intermittent mechanical infusion and stirring, thus facilitating a potentiostatic deposition route and promoting homogeneity of deposition. Graphite electrodes were produced at densities of 0.920, 1.026 and 1.188 g/cm³ and their suitability for constitution in a HCE assessed. The surface area of the nickel component of the HCE was varied from 100% to about 60 and 30% surface area and combined with the graphite electrode to form HCE constitutions designated as triplet, doublet and singlet respectively. Deposition was done for about 8 hours in 1 M NiSO₄ using the different HCE constitutions, an Ag/AgCl reference electrode and a custom deposition head which served as the working electrode. The mechanism of graphite electrode unraveling was observed to be the formation of oxygen and CO₂ due to oxidation reactions at the HCE. Graphite electrode of density 0.920 g/cm³ was selected for the HCE due to its extensive surface porosity, a characteristic determined as favourable to the mechanism of electrode unraveling. Co-deposition of graphite with nickel was observed to increase as nickel surface area was reduced from the triplet to singlet. SEM micrographs show partially and fully embedded graphite particles in the nickel matrix while the presence of nickel and graphite was affirmed.

In this current research, the solutions of modified Schrödinger equation (MSE) are presented for two companied potentials namely: modified inversely quadratic Hellmann potential and modified inversely quadratic potential (MIHQP), using generalization of Bopp’s shift method (instead to solving MSE with star product) and standard perturbation theory in extended quantum mechanics (EQM), we obtained modified Hamiltonian operator and corresponding modified eigenvalues in both three dimensional noncommutative space and phase (NC-3D: RSP) symmetries.

Colloidal metal nanoparticles are of great interest because of their use as catalysts, photocatalyst, adsorbent and sensors and their application in optical, electronic and magnetic devices. Capping agents are widely used in the synthesis of colloidal nano crystals for stabilizing the nanoparticles. The well dispersed Palladium nanoparticles (PdNP) supported on mesoporous γ-Al2O3 were prepared by using capping agents namely PVA, PVP, PEG and MEG using tetrahydrofuran as solvent. The catalytic properties of Pd-nanoparticle on mesoporous γ-Al2O3 were studied for hydrogenation model reaction.

The alumina supported palladium nanoparticles were characterized by using instrumental techniques namely BET surface area, HR-TEM and XRD. HR-TEM studies shows that the average particle size of Pd metal in the fresh and spent catalyst was in the range from 5 to 10 nm. The catalyst could be efficiently recycled for three times without losing catalytic activity and selectivity.

In the present study biomimetic synthesis of silver nanoparticles using Solanum nigrum and Cannabis sativa were explored. The biosynthesized silver nanocomposites were characterized using UV-VIS spectroscopy, DLS, TEM, FTIR and XRD. The characteristic surface plasmon resonance of Solanum nigrum and Cannabis sativa were recorded at 430 and 445 nm respectively. The average diameter of silver nanocomposites were 34.13 ± 3.10 and 70.93 ± 3.57 nm for Solanum nigrum and Cannabis sativa leaf extract respectively. The release of textile dyes into our surrounding water bodies has toxic effect on human health and marine life therefore removal of these dyes is necessary to protect environment. The nanotechnology has provided a new platform for waste water treatment. Hence the biosynthesized nanocomposites were employed for dye removal from wastewater. The effects of various parameters, such as time of incubation, concentration, pH, and temperature, were studied. The biosynthesized silver nanoparticles are most effective in dye removal at alkaline pH 9 and at 60ºC. The textile industry effluents have high pH and temperature which makes these nanoparticles more appropriate in treatment of these industry effluents. To elucidate the reusability, the decolorizing efficiency of biosynthesized silver nanocomposites were investigated upto 3 cycles.

Tuberculosis (TB) is an airborne infectious disease spreading very fast from person to person, which affect the health as well as socioeconomic conditions harshly. Though varieties of antitubercular drugs (ATDs) are available for its treatment, associated stern side effects restrict the patients to receive complete therapeutic benefits. Moreover, emergence of drug- resistant tuberculosis and co-infection of TB with HIV further worsen the situations. Polymeric formulations are introduced for progressive and long-term delivery of therapeutic agents, but owing to their noted limitations, performance is not up to the mark. In this juxtaposition, lipid based nano-formulations are introduced as an alternative to the polymic formulations in the management of TB with an intention to overcome side effects related to drugs along with limitations of polymeric formulations. The lipid based formulations comprise nanoemulsions, solid-lipid nanoparticles (SLNs), nano-structured lipid carriers (NLCs), liposomes, and niosomal systems, etc.

Liposomes have more promising antitubercular activity as its intended for targeted drug delivery especially to the infected part. Further mannosylation of liposomes offers tremendous results in TB chemotherapy as it directly binds to mannose receptors available on the surface of alveolar macrophages resulting mycobacterium destruction. Niosomes may have superior drug targeting ability, chemical stability, osmotic activeness and in vivo activity in comparison to that of liposomes. SLNs and manosylated SLNs are the advanced form of the lipid formulations which enhance the drug uptake at the infected organ and show significant in vivo anti-tubercular activity with reduced toxicity. Moreover, NLCs shows its satisfactory potential against MTb along with drug targeting action. Advancement on the development of miscellaneous or other vesicular lipid formulations are not encouraging in the field of tubercular chemotherapy. Hence, lipid based formulations could be successfully employed for targeted delivery of ATDs with promising anti-tubercular activity.