Publications by authors named "Ashok M Sajjan"

The focus of the study in this article is analyzing the electrochemical properties of molybdenum disulfide on miscible poly(methyl methacrylate)-poly(lactic acid) blends for supercapacitors. The interaction between molybdenum disulfide and miscible poly(methyl methacrylate)-poly(lactic acid) blends, affinity toward water, surface morphology, and mechanical properties are inspected by Fourier transform infrared spectroscopy, water contact angle, scanning electron microscopy, and universal testing machine, respectively. Among the developed membranes, 0.

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The electrochemical act of valve-regulated lead acid batteries can be enhanced by conductive materials like metal oxides. This work aims to examine the preparation and influence of zirconia on poly(vinyl alcohol) based gel valve-regulated lead acid battery. Characterizations like Fourier transform infrared spectroscopy, ionic conductivity, water retention study, cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge techniques were done.

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In the past few years, significant research efforts have been directed toward improving the electrochemical capabilities of supercapacitors by advancing electrode materials. The present work signifies the development of poly(lactic acid)/alloysite nano-clay as an electrode material for supercapacitors. Physico-chemical characterizations were analyzed by Fourier transform infrared spectroscopy, wide-angle X-ray diffraction, and a universal testing machine.

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In this study, the impact of graphene-doped poly(vinyl alcohol) hydrogels on gel-valve-regulated lead acid batteries was examined. The gel formulations were made by adding various amounts of graphene into the gel system comprising poly(vinyl alcohol) and sulfuric acid. Gel formulations were subjected to an ionic conductivity study and Fourier transform infrared spectroscopy (FTIR) to understand ionic mobility and material interaction, respectively.

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Extensive investigations were made and empirical relations were proposed for the thermal conductivity of mono-nanofluids. The effect of concentration, diameter, and thermal properties of participating nanoparticles is missing in the majority of existing thermal conductivity models. An attempt is made to propose a model that considers the influence of such missing parameters on the thermal conductivity of hybrid nanofluids.

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The gel electrolyte significantly influences gel valve-regulated lead acid battery performance. To address this, the paper describes the preparation of novel polymer gel electrolytes using poly (vinyl alcohol) (PVA) and tetraethylorthosilicate (TEOS) for valve-regulated lead-acid batteries. FTIR technique is used to confirm the chemical reaction between PVA and TEOS.

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Nanobacterial cellulose (NBC) was produced and incorporated into biodegradable poly(vinyl alcohol) (PVA) in different weight ratios to obtain polymer nanocomposite membranes. The physicochemical properties of the membranes were studied using Fourier transform infrared (FTIR) spectroscopy, a universal testing machine (UTM), thermogravimetric analysis (TGA), wide-angle X-ray diffraction (WAXD) techniques, and field emission scanning electron microscopy (FESEM). FTIR confirmed the consolidation of NBC into PVA by exhibiting significant changes in the peaks compared to NBC and PVA individually.

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Polyelectrolyte complex membranes (PECMs) were prepared by combining sodium carboxymethyl cellulose (NaCMC) and gelatin (Ge) with variations in the Ge content in the NaCMC matrix. Characterization methods, such as infrared spectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), contact angle analysis (CA), and universal testing machines (UTM) were used to investigate the physicochemical studies of the prepared membranes. The pervaporation characteristics of membranes with Ge content were investigated using an azeotropic mixture of water and bioethanol.

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Chitosan-capped silver nanoparticle (CS-capped AgNPs)-incorporated Poly(vinyl alcohol) (PVA) hybrid membranes were prepared by a solution-casting technique for ethanol dehydration via pervaporation. The incorporation of CS-capped AgNPs into the PVA membrane and its influence on membrane properties and pervaporation-separation process of azeotropic water/ethanol mixture was studied. The addition of CS-capped AgNPs into the PVA membrane reduced the crystallinity, thereby increasing the hydrophilicity and swelling degree of the hybrid membrane, supported by contact angle (CA) analyzer and swelling degree experiments, respectively.

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Natural polymers have attracted a lot of interest in researchers of late as they are environmentally friendly, biocompatible, and possess excellent characters. Membranes forming natural polymers have provided a whole new dimension to the separation technology. In this work, chitosan-gelatin blend membranes were fabricated using chitosan as the base and varying the amount of gelatin.

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Tetraethylorthosilicate (TEOS)-crosslinked poly(vinyl alcohol) (PVA) solution was prepared and treated with benzaldehyde 2 sulphonic sodium salt acid (B2SA) for sulfonation. Different contents of graphene were incorporated into B2SA-grafted PVA-TEOS hybrid membrane to improve the membrane stability, mechanical strength, and overall pervaporation performance of the membranes. Membranes were fabricated using the casting technique.

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Polystyrene-4-sulfonic acid co maleic acid sodium salt (PSSAMA_Na) capped silver nanoparticle (Ag_Np) embedded sodium alginate (Na-Alg) nanocomposite membranes have been developed to improve the pervaporation (PV) dehydration of bioethanol. The effect of PSSAMA_Na capped Ag_Nps on the micro-morphology, physicochemical properties and separation performance of the derived membranes was analyzed as a function of temperature at the azeotropic composition of the bioethanol-water mixture. WAXD analysis shows a decrease in crystalline domains with the increase in PSSAMA_Na capped Ag_Nps content and confirms the presence of Ag_Nps.

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