Karnatak University is a public state university in Dharwad district of Karnataka state, India. The University is recognized by University Grants Commission and accredited by National Assessment and Accreditation Council (NAAC). As of 2014, the university has been awarded 'Grade A' by the NAAC.Karnatak University was granted 'University with potential for Excellence' status by the University Grants Commission.
The present study describes the green synthesis of silver nanoparticles (AgNPs) using a fixed concentration of poly(vinyl alcohol) (PVA)/guar gum (GG)/gum ghatti (GGh) blend solution with different concentrations of AgNO3 solution at room temperature and fabrication of PVA/GG/GGh/AgNP nanocomposites (PGGA) using a simple solvent casting method. The effect of the inclusion of AgNPs on the surface morphology, mechanical and thermal properties of the obtained PGGA nanocomposites was studied using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy, a Universal Testing Machine (UTM), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC), respectively. Also, the results were compared with the blend film PVA/GG/GGh (PGGA-0) without AgNPs. The X-ray diffraction (XRD) study confirmed the formation of AgNPs (17-40 nm), and SEM analysis suggested homogeneous distribution of AgNPs in the polymer matrix. The presence of AgNPs does not change the position of IR peaks in PGGA nanocomposites. There was improvement in the hydrophobicity (63.6 +/- 3.3 degrees to 96.3 +/- 2.5 degrees) and thermal stability of PGGA nanocomposites compared to the PGGA-0 blend film. Further analysis of the results suggested an increase in the elongation at break of PGGA-4 nanocomposites with an increase in the concentration of AgNPs (0.2% w/v). Moisture adsorption was significantly decreased by the addition of AgNPs into the polymer matrix compared to the PGGA-0 blend film. The increase in AgNP content effectively inhibited the growth of bacteria. The soil burial test indicated biodegradation of the PGGA nanocomposites. Application studies on fresh coriander leaves confirmed that PGGA-1 films effectively enhanced shelf life and quality retention under ambient conditions. Improved moisture control, chlorophyll preservation, and sensory attributes highlight their practical potential in sustainable food packaging.
The synthesis of MgO nanoparticles (NPs) using Endocomia macrocoma leaf extract was successfully achieved and confirmed through various characterization techniques, including UV-vis spectroscopy, FTIR, XRD, DLS, FESEM with EDX, TEM, TGA, and DSC. UV–vis analysis revealed a bandgap of 3.81 eV and an Urbach energy of 5 meV. SEM/HRTEM images showed quasi-spherical MgO NPs with sizes ranging from 30 to 60 nm. The synthesised nanoparticles exhibited strong antibacterial activity against E. coli, P. aeruginosa, B. subtilis, and B. cereus, with MIC values of 180 and 240 µg/ml. Significant radical scavenging activity was observed, with an IC50 value of 125 µg/ml in the DPPH assay compared to standard ascorbic acid. Anticancer activity was demonstrated against esophageal (KYSE-30) and pancreatic (PANC2) cancer cell lines, with IC50 values of 54.41 µg/ml and 34.56 µg/ml, respectively. Anti-ROS analysis indicated 85–86
Marine organisms, particularly macroalgae, are globally recognized as key sources of valuable biomolecules with applications in the agricultural and pharmaceutical sectors. They are also an inexpensive source in developing countries with high population density, such as India, where pressing demands conflict with the sustainable use of resources. The abundance of Sargassum spp. in India could provide an opportunity to create cost-effective marine-derived natural products, and the implementation of an optimized extraction and scaling process could contribute to overcoming sustainability issues. Thus, the present study examines the nutritional, mineral, and fatty acid composition of Sargassum cinereum J. Agardh from the Karnataka coast. Ultrasound-assisted extraction (UAE) was used to optimize the yield of bioactive compounds using the Response Surface Methodology (RSM) with the Box-Behnken design (BBD). Carbohydrates were the most abundant (53.15%) macronutrients, followed by fiber (20%) and protein (13.35%) on a dry-weight basis. Fatty acid composition showed abundance of palmitic acid, with a varied mineral composition, similar to other macroalgae already in use as a feed ingredient. RSM-BBD analysis underscored the impacts of solvent concentration, extraction time, and the solid-to-solvent ratio on the yields of total phenolic content, total flavonoid content, and antioxidant activity. The optimized parameters provide clear evidence of the interaction effect, presented through second-order polynomial equations. Although differences may arise depending on sample processing techniques, geographical variability, storage conditions, and the possible degradation of sensitive compounds, the data obtained herein highlight the need for future studies, given the potential of Sargassum spp., which grows abundantly, is nutritionally and chemically rich, and can be a high-value compound and used for multiple purposes.
In this work, PbO2-rich (11 to 20 mol %) BaO + CaO + B2O3 + Y2O3 glasses were synthesized via the melt quenching method. The experimental measurements using a NaI(Tl) detector and Monte Carlo N-Particle (MCNP) simulation were employed to evaluate shielding parameters across the energy interval, which varied from 0.356 to 1.332 MeV. Both the experimental and simulated data confirm that the linear attenuation coefficient (LAC) of BBaCaYPb20 decreased from 0.734 +/- 0.086 cm(-1) at 0.356 MeV to 0.250 +/- 0.004 cm(-1) at 1.332 MeV. The measured NaI(Tl) results agreed within +/- 12% of the MCNP data. At 0.662 MeV, the prepared BBaCaYPb glasses outperformed several commercial radiation protection glasses, with LAC values up to 0.418 cm(-1). Furthermore, increasing the PbO2 concentration improved shielding performance by reducing the half-value layer and tenth-value layer values, and raising radiation protection efficiency by up to 18%.
This study presents a comprehensive analysis of peristaltic transport in a converge and diverge channel filled with a fractional second-grade nanofluid, incorporating the effects of surface roughness, Joule heating, and a periodic magnetic field. The mathematical model is developed under the assumptions of extended wavelength and minimal Reynolds number. The dimensional equations are transformed into a non-dimensional form using appropriate scaling variables. Caputo’s fractional derivative is employed to capture the memory effects inherent in complex fluids, and analytical solutions are obtained for the resulting system. Effects of boundary conditions on flow and thermal characteristics are analyzed and presented graphically. An analytical solution is constructed applying the Homotopy Analysis Method (HAM). Higher magnetic parameter corresponds to a reduction in fluid’s velocity. Heat transfer in the system is primarily driven by Joule heating, while magnetic parameters inversely affect fluid velocity. Increasing the Hartmann number from 10 to 20 reduces axial velocity by 33.12
