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Infections originating from pathogenic microorganisms can significantly impede the natural wound-healing process. To address this obstacle, innovative bio-active nanomaterials have been developed to enhance antibacterial capabilities. This study focuses on the preparation of nanocomposites from thermally reduced graphene oxide and zinc oxide (TRGO/ZnO). The hydrothermal method was employed to synthesize these nanocomposites, and their physicochemical properties were comprehensively characterized using X-ray diffraction analysis (XRD), High-resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared (FT-IR), Raman spectroscopy, UV-vis, and field-emission scanning electron microscopy (FE-SEM) techniques. Subsequently, the potential of TRGO/ZnO nanocomposites as bio-active materials against wound infection-causing bacteria, including Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, was evaluated. Furthermore, the investigated samples show disrupted bacterial biofilm formation. A reactive oxygen species (ROS) assay was conducted to investigate the mechanism of nanocomposite inhibition against bacteria and for further in-vivo determination of antimicrobial activity. The MTT assay was performed to ensure the safety and biocompatibility of nanocomposite. The results suggest that TRGO/ZnO nanocomposites have the potential to serve as effective bio-active nanomaterials for combating pathogenic microorganisms present in wounds., (© 2024. The Author(s).)

PMMA/PEG and PMMA/PEG doped with SiO 2 , TiO 2, and Al 2 O 3 were fabricated using the solution-casting technique. The composites were characterized by X-ray diffraction and scanning electron microscopy (FE-SEM), which revealed that the amorphous nature of PMMA/PEG blend doped with Al 2 O 3 was hindered by the crystalline nature of those doped with SiO 2 and TiO 2 . The absorption of PMMA/PEG blend doped with Al 2 O 3 is higher, band gap energies were decreased from 4.90 eV for PMMA/PEG blend to 4.03 eV, 3.09 eV, and 2.09 eV for SiO 2 , TiO 2 , and Al 2 O 3 doped PMMA/PEG blend, respectively. The dielectric constant, ε' has a high value (2 × 10 4 ) for samples PMMA/PEG and SiO 2 /PMMA/PEG. While dielectric loss ε ″ -values decreased to < 100 for TiO 2 /PMMA/PEG and Al 2 O 3 /PMMA/PEG. Further, the fabricated composite SiO 2 /PMMA/PEG led to improvement the optical and dielectric properties compared with PMMA/PEG for optoelectronic such as manufacturing of optical fiber cables application. The results show TiO 2 /PMMA/PEG and Al 2 O 3 /PMMA/PEG are multifunctional can be used as low-permittivity nanodielectric and substrates to design the next generation of flexible electronic devices., (© 2024. The Author(s).)

Designing and synthesis of cost-effective and improved methanol permeable and proton conductive membranes are the main challenges for preparation of polymeric electrolyte membrane (PEM). Herein, a cost-effective PEM membrane based on phosphorylated polyvinyl alcohol (PVA)-grafted-cellulose acetate (CA) was prepared by a solution-casting technique. Water and methanol uptakes of phosphorylated PVA/CA membranes were characterized as function with the molar ratio of CA. Additionally, structure and morphology of phosphorylated PVA/CA (Ph-PVA/CA) membranes were verified by FT-IR analysis, SEM investigation. Furthermore, ion exchange capacity (IEC), proton conductivity and methanol permeation of Ph-PVA/CA membranes were examined based on the concentration of OPA basically. The results manifested a perceptible improvement in proton conductivity from 0.035 to 0.05 S/cm at 25 and 70 °C, respectively using 600 μL of OPA, and IEC of 2.1 meq/g using 400 μL of OPA at ambient temperature. On the other hand, methanol permeability (P = 1.08 × 10 -10 cm 2 /s) was lower than Nafion 117 admirably. The optimum OPA concentration was 200 μL according to conductivity measurements (at 10% PVA, 150 μL GA, and CA 7%). Finally, prepared Ph-PVA/CA membranes exhibited enhancement in critical natures such as proton conductivity and IEC combined with its low-cost materials, which make them excellent candidate as PEM for DMFCs application., (© 2023. Springer Nature Limited.)

This paper presents a new phase-shift modulation for isolated dual active bridge (DAB) direct current-direct current (DC-DC) converter. The proposed technique aims to minimize the maximum current stress of the converter, which could directly increase the efficiency and reduce the device losses. This modulation technique controls the converter power through only two phase-shift angles or two degrees of freedom; one phase shift is used between the legs of its first bridge and the other one between the legs of the second bridge. Although the traditional single-phase shift (SPS) technique has only one degree of freedom, it suffers from many drawbacks in terms of high current stress and reverse circulating power flow, which decrease the converter efficiency. On the other hand, increasing the number of phase-shift angles can enhance the system performance but also increase the control complexity. Thus, a comparative analysis between the proposed modulation technique and the traditional SPS was conducted; the new method showed better performance in terms of current stress reduction, along with implementation simplicity., (© 2022. The Author(s).)

Di-indium tri-sulfuric (In 2 S 3 ) thin films are fabricated with annealing indium thin films in a sulfur environment. The effect of both annealing temperature and pressure on the structure, morphology, Raman, and photoluminescence (PL) spectroscopy has been studied. The X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) of the prepared thin films showed different structural phases and morphology with varying annealing temperature and pressure. Energy dispersive X-ray (EDX) analysis confirmed the chemical composition and the atomic ratio of In/S for the In 2 S 3 thin films. The optimum annealing conditions of In 2 S 3 thin films are 550 °C and 100 Torr. The outcome results revealed a new good growth method for In 2 S 3 thin films to be used for different applications., (© 2022. The Author(s).)