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Chemical pretreatment of lignocellulosic biomass (LCB) in the presence of an alkaline catalyst is one of the major pretreatment processes that recover cellulose, hemicellulose, and lignin at effective process conditions and also for the production of bioethanol. Replacement of conventional catalysts with waste‐derived catalysts in the pretreatment process will be helpful for the development of low‐cost biorefinery. The continuous impact of different mass transfer properties during the chemical pretreatment of LCB will affect the final yield of products at a high reaction time and has been reviewed in the current study. Intraparticle diffusion of an alkaline catalyst into LCB is going to determine the diffusion of the selected catalyst within the porous biomass structure, which helps in the enhancement of the final yield of the product recovery at low‐process conditions. The diffusion of the synthesized catalyst within the selected biomass during the chemical pretreatment process is a rate‐limiting step that influences the final recovery yield of desired products. Enhancement of the biomass pretreatment reaction through the assessment of the diffusivity using the modified Nernst–Einstein relation is also discussed. Determination of different unique mass transfer properties rate of diffusion, diffusivity flux, and mass transfer coefficient are also to be analyzed to advance the reaction rate of the pretreatment process. [ABSTRACT FROM AUTHOR]

In this study, biological synthesis of silver nanoparticles (AgNPs) using Senna auriculata flower extract for antibacterial activities was reported. The silver spectra compared to the plant extract show a rightward shift in AgNP peaks, indicating successful nanoparticle formation. The absorption band at 302 nm and the disappearance or shift of other peaks further confirm the synthesis. X‐ray diffraction (XRD) analysis reveals that the AgNPs synthesized with S. auriculata extract have an average crystallite size of 25 nm. Transmission electron microscopy (TEM) results exhibited a polydispersed, spherical shape with sizes ranging from 70 nm, in clear contrast to the electron microscope image that showed their spherical shape. When examining the selected area electron diffraction (SAED) image, a specific set of lattice planes was correlated with a specific spot. A histogram of AgNP particle size distribution can be seen. AgNPs were tested against four different strains of bacteria for their antibacterial effectiveness, including gram negative bacteria (Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus), as well as gram positive bacteria (S. aureus, d. Bacillus subtilis), at various concentrations of AgNP. The results of in vitro experiments indicate that AgNPs containing S. auriculata flowers inhibit amylase well. At two concentrations, ~16.03% and ~70.99%, AgNPs inhibit the reaction at low and high concentrations, respectively. [ABSTRACT FROM AUTHOR]

In this study, we synthesize nanostructured nickel oxide (NiO) and doped cobalt (Co) by combining nickel(II) chloride hexahydrate (NiCl2.6H2O) and sodium hydroxide (NaOH) as initial substances. We analyzed the characteristics of the product nanostructures, including their structure, optical properties, and magnetic properties, using various techniques such as x‐ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet absorption spectroscopy (UV–Vis), Fourier transform infrared (FTIR) spectroscopy, and vibrating sample magnetometers (VSM). The NiO nanoparticles doped with Co showed photocatalytic activity in degrading methylene blue (MB) dye in aqueous solutions. We calculated the degradation efficiencies by analyzing the UV–Vis absorption spectra at the dye's absorption wavelength of 664 nm. It was observed that the NiO‐doped Co nanoparticles facilitated enhanced recombination and migration of active elements, which led to more effective degradation of organic dyes during photocatalysis. We also assessed the electrochemical properties of the materials using cyclic voltammetry (CV) and impedance spectroscopy in a 1 mol% NaOH solution. The NiO‐modified electrode exhibited poor voltammogram performance due to insufficient contact between nanoparticles and the electrolyte solution. In contrast, the uncapped NiO's oxidation and reduction cyclic voltammograms displayed redox peaks at 0.36 and 0.30 V, respectively. [ABSTRACT FROM AUTHOR]

The different configurations of the composites originated with machine or human motion, and their mechanical stability for wearable electronics is in focus. Here, the study highlights that these configurations are critical for wearable devices. To achieve these aspects, the electroactive and dielectric silicone rubber (SR) was used as a host matrix. This SR not only provides flexibility, twisting, or stretchability for such devices, but its lightweight makes them comfortable for robust wearable devices. The reinforcing fillers such as graphite nanoplatelets (GNP) or diatomaceous earth (DE) and their hybrids are used. The electromechanical properties of the device were performed using the universal testing machine. The output voltage generated at 15 phr filler was 0.3 mV (GNP), 0.15 mV (DE), and 0.22 mV (hybrid). Similarly, the biomechanical properties were studied with human motion joints such as thumb pressing or wrist bending. The output voltage at 15 phr was best for thumb pressing and it was 0.42 mV (GNP), 0.18 mV (DE), and 0.25 mV (hybrid). In the same way, the mechanical aspects studied in this work are compressive modulus, tensile strength, and fracture strain. For example, the compressive modulus was 1.28 MPa (control) and increased at 15 phr filler to 2.44 MPa (GNP), 3.2 MPa (DE), and 2.75 MPa (hybrid). Similarly, the mechanical stretchability of the devices was 134% (control) and changed at 15 phr filler to 128% (GNP), 78% (DE), and 109% (hybrid). Overall, the work demonstrates the method to develop a device with high mechanical, electromechanical, and biomechanical properties and their usefulness for wearable electronic devices. [ABSTRACT FROM AUTHOR]

Herein, an attempt has been made to synthesize silver nanoparticles from Murraya koenigii leaf extract at room temperature. The synthesized materials are stable for several months. The UV‐vis spectrophotometric analysis is carried out to ensure the formation of silver nanomaterials. XRD pattern confirms the formation of polycrystalline silver nanomaterials with the cubic crystal structure. Irregularly shaped particles are observed under field emission scanning electron microscopic observations. Elemental studies show the presence of Ag and O elements. The synthesized nanomaterial is multi‐applicative and shows potential efficacy against pathogenic microorganisms like Pseudomonas aeruginasa and Staphylococcus aureus. The results show that the leaf extract of M. koenigii is an efficient bio‐reductant for the synthesis of silver nanomaterials. The synthesized nanoparticles show potent anti‐microbial activities against Gram‐positive and Gram‐negative bacteria under study. [ABSTRACT FROM AUTHOR]

In present research, walnut like copper sulfide is prepared via a facile single‐step potentiostatic electrodeposition method on conducting stainless steel substrate. The walnut like morphology of copper sulfide thin film lies of microplates and further microplates converted to nanogranuals, by means of a change in deposition time and thickness. Copper sulfide thin film electrode reveals a specific capacitance of 132 F g−1 at 50 mA cm−2. The film thickness changes with deposition time. The films acquire maximum thickness of 610 nm for 25 min of deposition. X‐ray diffraction analysis revels that the CuS thin films is polycrystalline in nature and the crystallite size is 29 nm. The peak at 612 cm−1 in the Fourier transform infrared spectroscopy spectra confirms the formation of CuS. The wettability study shows the hydrophilic nature, the contact angle of water with CuS electrode is 66°, and the charge transfer resistance of CuS electrode is 7.78 Ω. [ABSTRACT FROM AUTHOR]