Journal Articles
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Item Computational fluid dynamic approach to understand the effect of increasing blockage on wall shear stress and region of rupture in arteries blocked by arthesclerotic plaque(UK Simulation Society Clifton Lane Nottingham NG11 8NS, 2016) Hegde, S.S.; Deb, A.; Nagesh, S.Computational bio-mechanics is developing rapidly as a non-invasive tool to assist the medical fraternity to help in both diagnosis and prognosis of human body related issues such as injuries, cardio-vascular dysfunction, atherosclerotic plaque etc. Any system that would help either properly diagnose such problems or assist prognosis would be a boon to the doctors and medical society in general. This project is an attempt to use numerical analysis techniques; in particular, computational fluid dynamics (CFD) to solve hemodynamics related problems. The mathematical modeling of the blood flow in arteries in the presence of successive blockages has been analyzed using CFD technique. Different cases of blockages in terms of percentages have been modeled to study the effect of blockage on wall shear stress values and also the effect of increase in Reynolds number on wall shear stress values. The concept of fluid structure interaction (FSI) has been used to study the effect of increasing von Mises stress on arteries and to determine the region of rupture in arteries. The simulation results are validated using in vivo measurement data from existing literature. © 2016, UK Simulation Society. All rights reserved.Item Dengue detection: Advances and challenges in diagnostic technology(Elsevier Ltd, 2022) Hegde, S.S.; Badekai Ramachandra, B.R.Virus-borne infectious illnesses may quickly escalate into unpleasant pandemics, wreaking havoc on the global populace and disrupting daily life. As a result, these factors influence the global economy, resulting in joblessness, physical, psychological, emotional stress, and posing a threat to human life. Dengue disease is known as one of the most dangerous illnesses for humans. A DENV infection may have no symptoms or symptoms that are similar to those of other viral infections. As a result, early detection of this virus infection is more important to track disease spread and protect society from its harmful effects. This article provides an overview of dengue disease, the working principles, the significance of the various conventional and biosensor detection strategies, the benefits and problematic conditions of the reported methods. The present hurdles of transferring laboratory research into real-world technological implementations and the future possibilities for detecting devices for viral diagnosis are highlighted in this study. © 2021 The Author(s)Item Properties of Mn3O4 thin film electrodes prepared using spray pyrolysis for supercapacitor application(Elsevier Ltd, 2023) Pramitha, A.; Hegde, S.S.; Badekai Ramachandra, B.R.; George, S.D.; Sudhakar, S.N.; Raviprakash, R.Film electrodes are made by depositing a thin layer of an electroactive material onto a conductive substrate. The performance of thin film electrodes in energy storage devices is significantly governed by their preparative conditions, particularly the molar concentration of the initial precursor. In the current study, the preparation of Mn3O4 thin film electrodes utilizing the chemical spray pyrolysis technique is discussed. The effect of molar concentration on the structural, morphological, and electrochemical properties of the thin film electrodes was thoroughly investigated using techniques including X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) studies. Additionally, X-ray photoelectron spectroscopy (XPS) was employed to gain more insight into the oxidation states of the sample with the best electrochemical performance. Findings suggested that the molar concentration considerably affects the crystallite size, surface area, surface roughness, and wettability, which would directly impact the functionality of the electrode. It was concluded that the electrode deposited using the molar concentration of 0.06 M showed significantly improved performance according to the electrochemical measurements. The areal capacitance of up to 105.3 mF/cm2 in the aqueous electrolyte was recorded from CV measurements at a scan rate of 5 mVs−1. These electrodes could be an option for low-cost, environmentally friendly electrochemical capacitors if prepared under optimal deposition conditions. © 2023 Elsevier B.V.Item Elucidating the Role of Copper-Induced Mixed Phases on the Electrochemical Performance of Mn-Based Thin-Film Electrodes(American Chemical Society, 2023) Adoor, P.; Hegde, S.S.; Badekai Ramachandra, B.R.; Sudhakar, S.N.; Raviprakash, R.Manganese oxide is a fascinating material for use as a thin-film electrode in supercapacitors. Herein, the consequences of copper incorporation on spray pyrolyzed manganese oxide thin films and their electrochemical performance were investigated. The Cu-incorporated manganese oxide thin films were deposited by spray pyrolysis, and their structural and electrochemical properties were thoroughly evaluated. The formation of the spinel Mn3O4 phase with effective Cu incorporation was confirmed by X-ray diffraction investigation. Through Raman studies, it was noticed that mixed phases of manganese oxide tend to form after Cu incorporation, and this result was also reflected in X-ray photoelectron spectroscopic studies. The surface morphology and roughness were also altered by the addition of copper. However, electrochemical measurements implied a reduction in the specific capacitance upon copper inclusion. The cyclic voltammetry test indicated a specific capacitance of 132 F/g for Mn3O4 electrodes, but a substantial drop for copper-incorporated samples due to the mixed manganese phase. The decremental tendency was further supported by galvanostatic charge-discharge studies and electrochemical impedance spectroscopic measurements. These results provide valuable insights into the effects of copper addition in manganese oxide thin-film-based electrodes for energy storage applications. © 2023 The Authors. Published by American Chemical SocietyItem Biomass waste-derived porous graphitic carbon for high-performance supercapacitors(Elsevier Ltd, 2024) Hegde, S.S.; Badekai Ramachandra, B.R.Porous carbons possess considerable appeal and are in high demand as materials that can be produced from biomass waste. This study presents the transformation of Tectona grandis (Teak) sawdust into porous carbon materials, referred to as Tectona grandis sawdust-derived porous carbon (TPC), through a cost-effective FeCl3-assisted carbonization process, followed by a KOH activation. TPC samples were synthesized by carbonization at different temperatures (650–850 °C) and characterized comprehensively. Structural analysis via X-Ray diffraction (XRD), Raman, and Fourier Transform Infrared Spectroscopy (FTIR) revealed a progressive enhancement in graphitic structure and reduction of functional groups with increasing activation temperature. Field emission scanning electron microscopy (FESEM) displayed the development of intricate hollow tube-like porous networks in TPC-850, with the highest specific surface area (1767.66 m2/g) and pore volume (1.43 cm3/g). Electrochemical investigations showcased the superior performance of TPC-850 as a supercapacitor electrode due to its high graphitic nature, large surface area, and well-structured porosity. The galvanostatic charge-discharge (GCD) measurements exhibited a high specific capacitance of 572 F/g at 0.5 A/g in a 6 M KOH electrolyte. The high-frequency semicircle and low-frequency steeper region in electrochemical impedance spectroscopy (EIS) further indicated reduced resistance and enhanced ion diffusion in TPC-850. Significantly, TPC-850 demonstrated remarkable electrochemical cyclic stability, retaining 95.83 % of its initial capacity even after undergoing 4500 cycles at a scan rate of 500 mV/s. The findings underscore the viability of TPC-850 as a high-performance supercapacitor electrode material, providing insights into harnessing renewable resources for advanced energy solutions. This work highlights the potential of utilizing waste biomass for energy storage applications and demonstrates the feasibility of converting it into efficient porous carbon materials with substantial graphitization and porosity. © 2023 Elsevier LtdItem Sustainable energy storage: Mangifera indica leaf waste-derived activated carbon for long-life, high-performance supercapacitors(Royal Society of Chemistry, 2024) Hegde, S.S.; Badekai Ramachandra, B.R.Biomass waste-derived activated carbon has a wide range of applications, including air and water purification, gas separation, energy storage, and catalysis. This material has become increasingly popular in recent years as a result of the growing demand for sustainable and eco-friendly materials. In this study, Mangifera indica leaf waste-derived activated carbon has been investigated as an electrode material for high-performance supercapacitors. The dried Mangifera indica leaves were first carbonized using FeCl3 and then activated using KOH to increase their surface area and pore structure at different temperatures. The activated carbon prepared at 725 °C has shown a high specific capacitance of 521.65 F g−1 at a current density of 0.5 A g−1 and also achieved an energy density of 17.04 W h kg−1 at a power density of 242.50 W kg−1 in the 6 M KOH electrolyte. Significantly, it has demonstrated remarkable electrochemical cycling stability, retaining 96.60% of its initial capacity even after undergoing 10 001 cycles at a scan rate of 500 mV s−1. The superior electrochemical performance of the activated carbon can be attributed to its high surface area of 1232.63 m2 g−1, well-distributed pore size, and excellent degree of graphitization, which all facilitate the rapid diffusion of ions and enhance the accessibility of the electrolyte to the electrode surface. Hence, this study provides a promising route for utilizing waste biomass as a low-cost, sustainable electrode material for energy storage devices. © 2024 The Royal Society of Chemistry.Item Impact of electrolyte concentration on electrochemical performance of Cocos nucifera Waste-Derived High-Surface carbon for green energy storage(Elsevier Ltd, 2024) Hegde, S.S.; Badekai Ramachandra, B.R.The increasing popularity of utilizing biomass's natural structure represents a promising avenue for sustainable innovation, as it taps into the inherent characteristics of organic materials to address various environmental and industrial challenges. Researchers and industries continue to explore the full potential of biomass in creating more sustainable and efficient solutions. The transformation of biomass into carbon materials is an indirect means of utilizing CO2 as a carbon source, thus contributing to the sustainable development of energy storage technologies and also in pollution reduction. In the quest for sustainable energy solutions, this research unveils a cost-effective approach to supercapacitor development by harnessing the untapped potential of Cocos nucifera trunk sawdust-derived high-surface carbon (CHSC). Through a meticulous process involving ZnCl2 treatment and KOH activation at varying temperatures, CHSC-700 emerges as a standout electrode material with exceptional structural characteristics, boasting enhanced graphitization and a specific surface area of 1153.72 m2/g. Further, the study delved into the nuanced relationship between electrolyte concentration and supercapacitor performance, pinpointing 6 M KOH as the optimal condition. In 6 M KOH, the electrode exhibits a maximum specific capacitance of 559.27F/g at the current density of 0.5 A/g with outstanding cyclic stability, retaining 80.37 % capacitance after 20,000 cycles and an impressive energy density of 18.92 Wh/kg and power density of 246.75 W/kg. This systematic exploration provides valuable data for understanding the biomass-derived carbon electrode's behaviour under various electrolyte concentrations, offering crucial information for optimizing its performance in practical applications, such as energy storage devices. © 2024 Elsevier LtdItem Unveiling the Versatile Applications of Cobalt Oxide-Embedded Nitrogen-Doped Porous Graphene for Enhanced Energy Storage and Simultaneous Determination of Ascorbic Acid, Dopamine and Uric Acid(Institute of Physics, 2024) Agadi, N.P.; Hegde, S.S.; Teradal, N.L.; Badekai Ramachandra, B.R.; Seetharamappa, J.The advancement of electrode materials is essential for addressing the energy and biomedical challenges. A multi-functional approach was employed to create a new electrode material of cobalt oxide-embedded nitrogen-doped porous graphene (Co3O4@NpG) for sensing and energy storage applications. In the present study, we have fabricated a new electrochemical sensing platform based on Co3O4@NpG. The sensing performance and selective detection capability of the demonstrated sensor was optimized and tested by determining dopamine (DA), uric acid (UA), and ascorbic acid (AA) simultaneously in analyte fortified biological samples. The sensing response is noticed to be linearly dependent upon the concentration of AA, DA, and UA in the range of 0.1-450, 0.1-502, and 0.2-396 μM, respectively. This material also showed good electrochemical energy storage performance when assessed as a supercapacitor electrode. The Co3O4@NpG electrode material showcased a remarkable specific capacitance of 314.58 Fg−1, an energy density of 10.06 Wh kg−1 at a power density of 240 Wkg−1 at 0.5 Ag−1, in a 6 M KOH electrolyte, along with excellent long-term cycling stability. Hence, the material Co3O4@NpG stands out as a promising multifunctional electrode candidate, excelling in the precise simultaneous detection of critical biomolecules besides exhibiting superior energy storage performance. © 2024 The Electrochemical Society (“ECS”). Published on behalf of ECS by IOP Publishing Limited. All rights, including for text and data mining, AI training, and similar technologies, are reserved.Item Electrochemical performance and structural evolution of spray pyrolyzed Mn3O4 thin films in different aqueous electrolytes: effect of anions and cations(Royal Society of Chemistry, 2024) Adoor, P.; Hegde, S.S.; Badekai Ramachandra, B.R.; George, S.D.; Raviprakash, R.This work presents the impact of cycling in different cationic and anionic aqueous electrolytes on the electrochemical storage performance of the Mn3O4 thin film electrode prepared using the chemical pyrolysis method. Studies on the as-deposited electrode confirmed the formation of Mn3O4 phase. Extensive electrochemical analysis was performed using Na2SO4, NaCl, Li2SO4, K2SO4, and MgSO4 electrolytes to examine the influence of cations and anions on charge storage behaviour. Considerable changes were observed in the specific capacitances owing to different ionic sizes as well as hydrated ionic radius of the electrolyte ions. Accordingly, the electrode unveiled a good performance showing a specific capacitance of around 187 F g−1 at 0.5 A g−1 in K2SO4 electrolyte. Further, the electrode properties are examined after 500 CV cycles to trace the changes in the structural and morphological properties. X-ray diffraction (XRD) and Raman spectroscopic studies illustrate a partial phase transformation of electrodes from Mn3O4 to MnO2 irrespective of the electrolytes. These results are further corroborated with X-ray photoelectron spectroscopic (XPS) analysis where there was an increment in the oxidation state of manganese. It has been observed that the surface properties were significantly changed with cycling, as manifested by the wettability studies of the electrodes. The obtained results brings out the significance of electrolyte ions on the charge storage characteristics of Mn3O4 thin film electrodes in light of their possible application in electrochemical capacitors. © 2024 The Royal Society of Chemistry.Item A novel and ultrasensitive high-surface porous carbon-based electrochemical biosensor for early detection of dengue virus(Elsevier Ltd, 2024) Hegde, S.S.; Naik, S.; Badekai Ramachandra, B.R.; Mishra, P.; Udayakumar, D.; Ahmed, M.U.; Santos, G.N.Dengue fever, a mosquito-borne viral infection, poses a significant global health threat, and early diagnosis is crucial for effective disease management. The utilization of advanced materials in the design ensures an improved surface area, facilitating a heightened interaction between the sensor and the target. In this study, the incorporation of biomass-derived high-surface porous carbon-based materials not only contributed to the sensor's sensitivity but also ensured a cost-effective and scalable manufacturing process. The electrochemical nature of the biosensor added a layer of precision to the detection process and offered a reliable, rapid method for identifying the infection of the dengue virus. The enhanced sensitivity of the biosensor allowed the detection of even trace amounts of the NS1 protein, enabling early diagnosis in the initial stages of dengue infection. The system exhibited a high sensitivity with a wide linear range between 1 pg/mL and 100 μg/mL, and the extremely low detection limit of 0.665 pg/mL ranks this as one of the most efficient biosensors for the detection of dengue virus NS1 protein. Selectivity studies, coupled with computational insights, showcased the biosensor's prowess in distinguishing NS1 protein from potential interfering substances, laying the foundation for reliable diagnostics in complex biological matrices. Real sample analysis using human serum spiked with NS1 protein offers a tantalizing glimpse into the transformative potential of biosensors in real-world scenarios. This innovative biosensor holds great promise for addressing the pressing need for early detection of dengue virus infections. © 2024 The Authors