Search

Nano bacterial cellulose (NBC) being a biopolymer has unique physical and chemical properties with high biocompatibility. It is pure cellulose with nanometer size, produced by certain group of bacteria. Its properties can be further improved by combining with poly(vinyl alcohol) (PVA), which is a fascinating polymer soluble in water and biocompatible. Composite films of PVA and NBC were prepared by solution casting method. Composite films of PVA-NBC (0,1,2,3,4,5 %) were tested for major packaging properties like water vapor transmission rate, swelling measurement, film solubility and moisture retention capacity. Among all concentration films, film with 5 % NBC- PVA showed better results for all the tests. Films were also checked for antimicrobial properties against spoilage-causing bacteria and fungi. Further, the films were applied to study the shelf life in the Mitli Banana (Musa sp.) followed by Organoleptic evaluation during storage. Results showed that the banana packed with 5 % NBC- PVA film has retained maximum acceptable characters than other packages.

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. The optimized gel system exhibited a discharge capacity of 198.45 μAh cm−2 at the current density of 0.6 mA cm−2. The battery cell with an optimized gel matrix displayed a maximum discharge capacity of 22.5 μAh at a current of 20 μA. After 500 continuous cycles, the battery attained a discharge capacity retention of 91 %. The presence of zirconia will increase the electrochemical performance of gel valve-regulated lead acid batteries.

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, 0.75 wt% of molybdenum disulfide on poly(methyl methacrylate)-poly(lactic acid) shows better electrochemical performances. It exhibits a maximum specific capacitance of 255.5 F g−1 at a current density of 1.00 mA g−1, maximum energy density of 22.7 Wh kg−1, and maximum power density of 360 W kg−1. A cycle study reveals 92% capacitance retention after 2500 cycles. The designed supercapacitor device shows a maximum specific capacitance of 1240 μF g−1 at a current density of 0.5 μA g−1, maximum energy density of 43 μWh kg−1, and maximum power density of 700 μW kg−1. Flexible membranes of molybdenum disulfide are expected to be a potent combination for supercapacitor applications.

In order to operate photovoltaic (PV) systems using maximum power point tracking (MPPT), three distinct combinations of controllers and converters are proposed in this research and compared. Using MATLAB/Simulink simulation, these strategies are assessed based on the output parameters of time, power, and current. The demand on power production has increased manifold in recent years and on the other hand, the conventional resources utilized for it will be vanished in near future. The requirement of PV based generation is getting increased. The procedure of getting solar energy from a solar panel is common. With MPPT, here the output obtained must be the same quantity of energy even when the source of that energy is partially available. Climate change and other issues could be to blame for this inefficiency. In this project three distinct converters and three distinct controllers have been compared. All three converters are linked to each controller individually, and measurements of current, voltage, and power are analysed. By which the result is obtained. After the comparison of nine outputs, the most powerful and efficient combination is identified. By doing this, the converters and controllers produce high D.C voltage. Direct voltage transmission to the MMI. A.C. voltage is created by converting D.C. voltage. Increase the MMI's output by doing this. The voltage generated by the MMI is sent to the grid for domestic usage. Even when the source is not readily available, the solar panel's voltage can still be used.

Bioplastics are plastics derived from natural resources like corn starch, biomass, sugarcane bagasse, and food waste. Unlike fossil fuel-based plastics, they are bio-degradable entirely or partially. Therefore, bioplastics are relatively less harmful to the environment. Cellulose and starch-based bioplastics are already used for applications like packaging, cutlery, bowls, straws. However, their cost and performance cannot match the conventional plastics. The present study was aimed to produce bioplastic from food waste material. As a result, orange peel is chosen because of its high cellulose content and good availability. The bio-plastic film from orange peel was produced using simple laboratory techniques. Its identification for potential applications is the new area of work. The developed film blends with glycerol as a plasticizer have indicated consistent and promising results. This has excellent strength, flexibility, and disintegration in soiling conditions, morphologically having a rough surface, and confirms the film's bio-degradability nature. Characterization methods such as Fourier transform infrared (FTIR) spectroscopy, Thermal gravimetric analysis (TGA), powderX-ray diffraction (XRD), and Scanning electron microscope (SEM) analysis confirmed that the developed material's physicochemical and surface morphology belonged to bio-based plastic. A simple, novel, and economic process are described in the manufacturing of bio-based plastic.

Decision making is facilitated by categorical neuronal responses, which robustly signal a winner despite input noise. In this study, the authors demonstrate that a donut-like inhibition motif effectively generates such categorical responses.

The performance of electrochemical supercapacitors is greatly affected by electrodes, which are considered one of the most significant components. This article sheds light on manganese dioxide (MnO2)-incorporated poly(methyl methacrylate) (PMMA) membranes as electrodes for supercapacitor applications. The interaction between MnO2 and PMMA is justified by Fourier transform infrared spectroscopy. The surface morphology of MnO2@PMMA membranes was observed using scanning electron microscopy and atomic force microscopy. Techniques such as cyclic voltammetry and electrochemical impedance spectroscopy indicated that a 7.5 wt% MnO2@PMMA membrane exhibited the highest electrochemical performance. GCD tests revealed that the 7.5 wt% MnO2@PMMA membrane showed a maximum specific capacitance of 361 F g−1 at a current density of 125 mA g−1 with a maximum energy density of 144 W h kg−1 and maximum power density of 1135 W kg−1. The membrane displayed 87% capacitance retention after 5000 cycles. The fabricated interdigital microsupercapacitor device revealed the highest specific capacitance of 528 mF g−1 at a current density of 0.15 mA g−1 with a maximum energy density of 47 mW h kg−1 and maximum power density of 400 mW kg−1. [ABSTRACT FROM AUTHOR]

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. Cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge–discharge techniques were employed to evaluate electrochemical characteristics. The optimized poly(lactic acid)/halloysite nano-clay film revealed the highest specific capacitance of 205.5 F g−1 at 0.05 A g−1 current density and showed 14.6 Wh kg−1 energy density at 72 W kg−1 power density. Capacitance retention of 98.48% was achieved after 1000 cycles. The microsupercapacitor device presented a specific capacitance of 197.7 mF g−1 at a current density of 0.45 mA g−1 with 10.8 mWh kg−1 energy density at 549 mW kg−1 power density.

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, 0.75 wt% of molybdenum disulfide on poly(methyl methacrylate)-poly(lactic acid) shows better electrochemical performances. It exhibits a maximum specific capacitance of 255.5 F g−1 at a current density of 1.00 mA g−1, maximum energy density of 22.7 Wh kg−1, and maximum power density of 360 W kg−1. A cycle study reveals 92% capacitance retention after 2500 cycles. The designed supercapacitor device shows a maximum specific capacitance of 1240 μF g−1 at a current density of 0.5 μA g−1, maximum energy density of 43 μWh kg−1, and maximum power density of 700 μW kg−1. Flexible membranes of molybdenum disulfide are expected to be a potent combination for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Abstract The main goal of the present work was to develop a value-added product of biodegradable material for sustainable packaging. The use of agriculture waste-derived carboxymethyl cellulose (CMC) mainly is to reduce the cost involved in the development of the film, at present commercially available CMS is costly. The main focus of the research is to translate the agricultural waste-derived CMC to useful biodegradable polymer suitable for packaging material. During this process CMC was extracted from the agricultural waste mainly sugar cane bagasse and the blends were prepared using CMC (waste derived), gelatin, agar and varied concentrations of glycerol; 1.5% (sample A), 2% (sample B), and 2.5% (sample C) was added. Thus, the film derived from the sample C (gelatin + CMC + agar) with 2.0% glycerol as a plasticizer exhibited excellent properties than other samples A and B. The physiochemical properties of each developed biodegradable plastics (sample A, B, C) were characterized using Fourier Transform Infra-Red (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA). The swelling test, solubility in different solvents, oil permeability coefficient, water permeability (WP), mechanical strength of the produced material was claimed to be a good material for packaging and meanwhile its biodegradability (soil burial method) indicated their environmental compatibility nature and commercial properties. The reflected work is a novel approach, and which is vital in the conversion of organic waste to value-added product development. There is also another way to utilize commercial CMC in preparation of polymeric blends for the packaging material, which can save considerable time involved in the recovery of CMC from sugarcane bagasse.

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. Electrochemical analyses such as cyclic voltammetry and electrochemical impedance spectroscopy were applied to optimize the concentration of PVA-TEOS polymer gel electrolyte. The optimum concentration of polymer gel electrolyte was determined as 20 wt% of TEOS in PVA (PE-1) with higher anodic peak and lower Rs and Rct values. The Galvanostatic charge–discharge tests were performed on the optimized gel system prototype battery. The highest capacity of 6.86 × 10−5 Ah at a current density of 0.2 mA cm−2 was achieved with an excellent capacity retention ratio of 85.7% over 500 cycles. The exceptional cycle performance and high capacity make PVA-TEOS gel electrolyte a promising candidate for practical battery application.

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. The obtained data revealed that the membrane with 15 mass% of Ge (M-3) showed a maximum flux of 7.8403 × 10−2 kg/m2·h with separation selectivity of 2917 at 30 °C. In particular, the total and water flux of PECMs are shown as very close to each other indicating that the fabricated membranes could be employed to successfully break the azeotropic point of water–bioethanol mixtures. Using temperature-dependent permeation and diffusion data, the Arrhenius activation parameters were calculated, and the obtained values of water permeation (Epw) were considerably smaller than bioethanol permeation (EpE). Developed membranes showed the positive heat of sorption (ΔHs), suggesting that Henry’s sorption mode is predominant.

The combustion phenomena are always complex in nature due to the involvement of complex series and parallel reactions. There are various methods that are involved in analyzing combustion phenomena. Viscosity is the first and foremost factor that acts as the DNA of fuel. By evaluating the viscosity, it is possible initially to understand the combustion phenomena. Thermophysical and transport properties are helpful during the intensification of the combustion process. Combustion experiments are economically infeasible and time-consuming processes. Combustion simulations demand excellent computational facilities with detailed knowledge of chemical kinetics. So far, the majority of researchers have focused on analyzing coal combustion phenomena, whereas less work has been carried out on liquid fuels, especially biodiesel combustion analysis. Traditional engine testing provides only performance parameters, and it fails to have oversight of the thermodynamic aspects. The application of thermal analysis methods in combustion research is useful in the design, modeling, and operation of the systems. Such investigations are carried out extensively in the combustor, engine, and process industries. The use of differential scanning calorimetry (DSC) and thermogravimetry (TG) to assess the properties of biofuels has been attracting researchers in recent years. The main objective of this paper is to discuss the application of TGA and DSC to analyze heat flow, enthalpy, thermal stability, and combustion indexes. Moreover, this paper reviews some of the other aspects of the kinetics of combustion, transport properties’ evaluation, and combustion simulations for biodiesels and their blends. TG curves indicate two phases of decomposition for diesel and three phases for biofuel. The B-20 blend’s (20% biodiesel and 80% diesel) performance was found to be similar to that of diesel with the combustion index and intensity of combustion nearly comparable with diesel. It is thermally more stable with a high offset temperature, confirming a longer combustion duration. A case study reported in this work showed diesel and B20 JOME degradation start from 40 °C, whereas jatropha oil methyl ester (JOME) degradation starts from 140 °C. JOME presents more decomposition steps with high decomposition temperatures, indicative of more stable compound formation due to the oxidation process. The peak temperature of combustion for diesel, JOME, and B20 JOME are 250.4 °C, 292.1 °C, and 266.5 °C, respectively. The ignition index for the B-20 blend is 73.73% more than that of diesel. The combustion index for the B20 blend is 37.81% higher than diesel. The B20 blend exhibits high enthalpy, better thermal stability, and a reduced peak temperature of combustion with an improved combustion index and intensity of combustion nearly comparable to diesel.

One of the factors that affect the performance of the value‐regulated lead acid (VRLA) battery is gel electrolyte. To address this, a gel polymer electrolyte comprising halloysite nano‐clay in a poly(vinyl alcohol) matrix is formulated and the electrochemical performance is studied. Interaction between halloysite nano‐clay and poly(vinyl alcohol) is confirmed by Fourier transform infrared spectroscopy (FTIR). To optimize the concentration of gel electrolytes, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) are utilized. Galvanostatic charge‐discharge (GCD) tests are performed on a prototype battery comprising of an optimized gel electrolyte. The battery shows the highest discharge capacity of 6.858 μAh at 7.5 μA cm−2 current density and achieves admirable discharge capacity retention of 87.5% after 500 cycles. Hydrogen‐bonded halloysite nano‐clay and poly(vinyl alcohol) can be employed as gel electrolytes in VRLA batteries. [ABSTRACT FROM AUTHOR]

Surface Water Mapping (SWM) is essential for studying hydrological and ecological phenomena. SWM holds significant importance in water resource management, environmental conservation, and disaster preparation. Recently, rapid urbanization, overutilization, and environmental degradation have seriously impacted surface water bodies. Rapid advancement in remote sensing data and technologies has promoted the SWM to a new era. Timely and precise SWM is crucial for water resource preservation and planning. This paper critically reviews the extraction of surface water bodies from optical sensors using Spectral Indices (SI), Machine Learning (ML), Deep Learning (DL), and Spectral unmixing with a comprehensive overview of satellite data, study areas, methodologies, results, advantages, and disadvantages, especially over the last decade. The extensive review of SWM reveals that DL outperforms ML and SI. DL outperforms other methods because it incorporates crucial elements in network design, like skip connections, dilation convolution, attention mechanisms, and residual blocks. The spectral unmixing addresses the mixed pixel misclassification problem. Some SI, ML, and DL methods are implemented, and the results are discussed. Integrating the DL technique with spectral unmixing, fusing multisource data (SAR and optical) and integrating it with ancillary data (DEM) is the future direction for improved SWM. [ABSTRACT FROM AUTHOR]

Polymer-based nanocomposites are being considered as replacements for conventional materials in medium to high-temperature applications. This article aims to discover the synergistic effects of reinforcements on the developed polymer-based nanocomposite. An epoxy-based polymer composite was manufactured by reinforcing graphene nanoplatelets (GNP) and h-boron nitride (h-BN) nanofillers. The composites were prepared by varying the reinforcements with the step of 0.1 from 0.1 to 0.6%. Ultrasonication was carried out to ensure the homogenous dispersion of reinforcements. Mechanical, thermal, functional, and scanning electron microscopy (SEM) analysis was carried out on the novel manufactured composites. The evaluation revealed that the polymer composite with GNP 0.2 by wt % has shown an increase in load-bearing capacity by 265% and flexural strength by 165% compared with the pristine form, and the polymer composite with GNP and h-BN 0.6 by wt % showed an increase in load-bearing capacity by 219% and flexural strength by 114% when compared with the pristine form. Furthermore, the evaluation showed that the novel prepared nanocomposite reinforced with GNP and h-BN withstands a higher temperature, around 340 °C, which is validated by thermogravimetric analysis (TGA) trials. The numerical simulation model is implemented to gather the synthesised nanocomposite’s best composition and mechanical properties. The minor error between the simulation and experimental data endorses the model’s validity. To demonstrate the industrial applicability of the presented material, a case study is proposed to predict the temperature range for compressor blades of gas turbine engines containing nanocomposite material as the substrate and graphene/h-BN as reinforcement particles.

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. Fourier transform infrared spectroscopy (FTIR) demonstrated the formation of polymeric matrix between PVA and CS and also the binding of AgNPs onto the functional group of CS and PVA, which was also reflected in the microstructure images demonstrated by scanning electron microscopy (SEM) and by 2θ angle of wide-angle X-ray diffraction (WAXD). The effect of CS-capped AgNPs on the thermal stability of the hybrid membrane was demonstrated by differential scanning calorimetry (DSC) and thermogravimetric analyzer (TGA). These characteristics of the hybrid membrane positively impact the efficiency of the dehydration of ethanol, as indicated by pervaporation experiments. The best performances in total flux (12.40 ± 0.20 × 10−2 kg/m2 h) and selectivity (3612.33 ± 6.03) at 30 °C were shown for CS-capped AgNPs PVA hybrid membrane containing 2 wt.% CS-capped AgNPs (M-4). This confirms that the developed hybrid membranes can be efficiently used to separate water from azeotropic aqueous ethanol.

Recent times sustained efforts have been made in the bottom-up approach and biological Ag nanoparticles synthesis, in present work synthesized silver nanoparticles via green synthesis from the Eichhornia crassipes (EC) leaf extract AgNPs at room temperature with pH of 10–12. Synthesized AgNPs characterized thoroughly for phase purity and morphology by various characterization techniques. Phytochemical activities of Eichhornia crassipes (EC) leaf extract were shown that main constituents flavonoids, quercetin enhances the conversion of Ag ​+ ​to Ag0. This is also confirmed through the electronic property (EHOMO and ELUMO) of EC leaf extract, which was analyzed through quantum chemical studies. Further the antibacterial activity of AgNPs was screened on E. coli and S. aureus. The result reveals that AgNPs has good antibacterial properties towards the bacteria E. coli. The AgNPs is dedicated also in testing the effectiveness of aluminum corrosion in the acid system at room temperature using Tafel plots, atomic absorption spectroscopy, and AC impedance spectroscopy techniques. Corroded aluminum pieces were observed by using the SEM technique.

The aim of the present work is the synthesis and characterization of iron oxide (Fe3O4) nanoparticles. These nanoparticles are coated with oleic acid and polyvinyl butyral and mixed with microspheres and further developed ferrofluids with silicon oil. Studies of the performance of the nanoparticles in these ferrofluids with and without coating agents were carried out. The nanoparticles were synthesized using the chemical co-precipitation technique and coated with oleic acid and polyvinyl butyral, and it further mixed with microsphere ferrofluids and developed using silicon oil. The prepared Fe3O4 nanoparticles and their coated forms of oleic acid and polyvinyl butyral were mixed with microspheres; furthermore, ferrofluids were developed with silicon oil. All forms of these ferrofluids are characterized for morphology and phase purity (SEM, XRD, and FTIR). The iron oxide (Fe3O4) nanoparticles have shown different magnetic properties, differentiating macroscopic iron oxide in suspended particles. The ratio of surface to volume increases along with the decrease in atomic size, essential for assessing the surface morphological properties. The magneto-rheological (MR) fluids were determined, and shear stress of Expancel microsphere mixed iron oxide nanoparticle with and without them was found almost equal. However, the ferrofluid with PVB coated nanoparticles and microspheres emerged as a stable rheological ferrofluid, sustaining high shear stress and low viscosity with increasing shear rate. Also, shear rates up to 650 s−1 have been observed, showing very high shear stress withstanding capacity. The stability and performance of the magnetic colloidal ferrofluids depend on the thermal contribution and the balance between attractive/repulsive interactions.

Nalini Kotekar,1 Anshul Shenkar,2 Ravishankar Nagaraj3 1Department of Anaesthesiology, JSS Academy of Higher Education and Research, Mysore, Karnataka, India; 2Department of Anaesthesiology, AJ Medical College and Research Centre, Mangalore, Karnataka, India; 3Department of Surgery, JSS Academy of Higher Education and Research, Mysore, Karnataka, India Abstract: Improving trends in global health care have resulted in a steady increase in the geriatric population. However, as the population ages, surgery is being performed more frequently in progressively older patients and those with higher prevalence of comorbidities. A significant percentage of elderly patients experience transient postoperative delirium following surgery or long-term postoperative cognitive dysfunction (POCD). Increasing age, educational level, pre-existing mental health, and comorbidities are contributory factors. Comprehensive geriatric assessment provides an objective evaluation on overall medical, social, mental, and functional well-being with scope for preoperative optimization. Preventive strategies for POCD target the surgical and patient-related factors as well as the utilization of the concept of stress-free anesthesia and surgery, that is, Enhanced Recovery After Surgery. This includes care bundles and protocols for the perioperative period which improves outcomes in the elderly. Research on biomarkers of neural injury in POCD is gaining momentum. Pharmacologic agents such as acetylcholine esterase inhibitors promise to have a vital role in the management of POCD but exhibit undesired side effects. Interventions to reduce oxidative stress and neuroinflammation could prove beneficial. Preventive strategies, early recognition, and management of perioperative risk factors seems to be, by far, the best modality to deal with POCD till further progress in therapeutic interventions evolve. Keywords: cognitive dysfunction, geriatric anesthesia, neuronal injury, neuroinflammation, enhanced recovery, prehabilitation

The development of radiation attenuation materials with lean cross-sections is the need of the hour. However, the inherent threat of radiations accompanying these processes is of major concern. Thus, in an attempt to shield unnecessary radiations, several novel materials have been fabricated alongside the conventional materials available. Yet, there is a need for cost-effective, efficient shielding materials that have good mechanical strength and effective shielding properties. The present work investigates ceramic composite behaviors and radiation shielding capacity reinforced with lead oxide nano-powder. Developed nano-lead-based cement composites were subjected to mechanical tests to determine flexural and compressive strengths to check their suitability for structural applications. Further, the gamma attenuation test of the composites was conducted to determine their neutron absorption capacity. The addition of nano-leadoxide in the control beams was varied from 0.7 to 0.95 and 1 wt.% of the ceramic matrix. The percentage of nano-leadoxide that gives the best results in both enhanced properties and economic aspects was determined to be 0.6 wt.% of the cement.