Numerical investigation on bioconvection flow of Oldroyd-B nanofluid with nonlinear thermal radiation and motile microorganisms over rotating disk

Journal of Thermal Analysis and Calorimetry - In this paper, the mechanism of radiative Oldroyd-B nanofluid flow over a rotating disk with activation energy and motile microorganisms is examined....     

Hydrothermally synthesized highly efficient binary silver strontium sulfide (AgSrS) for high-performance supercapattery applications

The increasing demand for sustainable energy has diverted researchers’ intentions toward electrochemical storage devices. This research aims to combine supercapacitors’ characteristics with batteries to create high-performance hybrid energy storage devices. The hydrothermal approach is used to synthesize silver sulfide (Ag₂S), strontium sulfide (SrS), and their composite silver strontium sulfide (AgSrS). XRD is used to evaluate the crystallinity, SEM is used to study the surface morphology, and XPS is used to determine the elemental composition of AgSrS. The BET measurements show a higher surface area of 22.23 m²g⁻¹ for AgSrS. The highest achieved specific capacity with AgSrS is 494.5 C g⁻¹ (137.36 mAh-g⁻¹). The best-tuned material, AgSrS, is then used as the anode in a powered hybrid device with activated carbon (A.C.) as the cathode terminal. This device provides an energy of 26.32 Wh-kg⁻¹ at a power of 800 W kg⁻¹. The device was also put through a durability test, which included 5000 consecutive cycles. After 5000 cycles, a columbic efficiency of 82% was achieved, with 96% capacity retention. This research shows that the composite material AgSrS can be utilized commercially for hybrid energy storage devices in the future.

     

Planar and non-planar ion acoustic shock waves in electron-positron-ion plasmas

Ion acoustic shock waves (IASW's) are studied in an unmagnetized plasma consisting of electrons, positrons and adiabatically hot positive ions. This is done by deriving the Kortweg-deVries-Burger (KdVB) equation under the small amplitude perturbation expansion method. The dissipation is introduced by taking into account the kinematic viscosity among the plasma constituents. It is found that the strength of ion acoustic shock wave is maximum for spherical, intermediate for cylindrical, and minimum for planar geometry. It is observed that the positron concentration, ratio of ion to electron temperature, and the plasma kinematic viscosity significantly modifies the shock structure. Finally, it is found that the temporal evolution of the non-planar IASW's is quite different by comparison with the planar geometry. The relevance of the present study with regard to the dense astrophysical environments is also pointed out.     

Magnetohydrodynamic flow of burgers fluid with heat source and power law heat flux

Here magnetohydrodynamic (MHD) two-dimensional (2D) flow of an incompressible Burgers material bounded by a permeable stretched surface is addressed. The boundary layer flow equations are modelled. Heat transfer is discussed for power law heat flux at the surface and heat source. Convergent series solutions are constructed. Clarification of different emerging variables is presented through graphs of velocity, temperature and local Nusselt number. The present solutions are matched with the available published work in a limiting case.     

Formulation and Evaluation of a Clove Oil-Encapsulated Nanofiber Formulation for Effective Wound-Healing

Wound-healing is complicated process that is affected by many factors, especially bacterial infiltration at the site and not only the need for the regeneration of damaged tissues but also the requirement for antibacterial, anti-inflammatory, and analgesic activity at the injured site. The objective of the present study was to develop and evaluate the natural essential oil-containing nanofiber (NF) mat with enhanced antibacterial activity, regenerative, non-cytotoxic, and wound-healing potential. Clove essential oil (CEO) encapsulated in chitosan and poly-ethylene oxide (PEO) polymers to form NFs and their morphology was analyzed using scanning electron microscopy (SEM) that confirmed the finest NFs prepared with a diameter of 154 ± 35 nm. The successful incorporation of CEO was characterized by Fourier transform infra-red spectroscopy (FTIR) and X-ray diffractometry (XRD). The 87.6 ± 13.1% encapsulation efficiency and 8.9 ± 0.98% loading of CEO was observed. A total of 79% release of CEO was observed in acidic pH 5.5 with 117% high degree of swelling. The prepared NF mat showed good antibacterial activity against Staphylococcus aureus and Escherichia coli and non-cytotoxic behavior against human fibroblast cell lines and showed good wound-healing potential.     

Catalytic nonthermal plasma using efficient cobalt oxide catalyst for complete mineralization of toluene

Research on Chemical Intermediates - The remarkable rise in industrial utilization of volatile organic compounds has increased their presence in environmental matrices, which is a menace for human...     

Effects of nonlinear thermal radiation and activation energy on modified second-grade nanofluid with Cattaneo–Christov expressions

Journal of Thermal Analysis and Calorimetry - The aim of the current contribution is to exploit the effects of nonlinear thermal radiation and activation energy on the flow of modified second-grade...     

Crystallographic Evidence for a Sterically Induced Ferryl Tilt in a Non‐Heme Oxoiron(IV) Complex that Makes it a Better Oxidant

Oxoiron(IV) units are often implicated as intermediates in the catalytic cycles of non‐heme iron oxygenases and oxidases. The most reactive synthetic analogues of these intermediates are supported by tetradentate tripodal ligands with N‐methylbenzimidazole or quinoline donors, but their instability precludes structural characterization. Herein we report crystal structures of two [Fe^IV(O)(L)]²⁺ complexes supported by pentadentate ligands incorporating these heterocycles, which show longer average Fe–N distances than the complex with only pyridine donors. These longer distances correlate linearly with log k₂′ values for O‐ and H‐atom transfer rates, suggesting that weakening the ligand field increases the electrophilicity of the Fe=O center. The sterically bulkier quinoline donors are also found to tilt the Fe=O unit away from a linear N‐Fe=O arrangement by 10°.