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Green synthesis of reduced graphene oxide using Plectranthus amboinicus leaf extract and its supercapacitive performance
A rapid, efficient, green and eco-friendly approach for the preparation of reduced graphene oxide (rGO) using Plectranthus amboinicus (Indian borage) leaves extract (PAE) is explored in this study. The improvement in the reduction process was studied by varying the concentration of graphene oxide (GO), temperature and time duration. The physical and chemical properties of rGO are studied using Raman spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction (XRD) and field emission scanning electron microscope. The result obtained from XRD analysis confirms the removal of an oxygen-containing functional group of GO significantly by PAE. Raman analysis showed a higher ID/IG ratio for rGO (1.297) than GO (1.07), which indicates a higher level of disorder in the rGO with a decrease in the average size of the sp2 domain. From the electrochemical studies, a significant specific capacitance of 92.05Fg1 (5mVs1) is obtained from the cyclic voltammetry (CV) curves and 73.20Fg1 (0.1Ag1) from the galvanostatic chargedischarge (GCD) curve. 2021, Indian Academy of Sciences. -
Morphological and Elemental Investigations on CoFeBO Thin Films Deposited by Pulsed Laser Deposition for Alkaline Water Oxidation: Charge Exchange Efficiency as the Prevailing Factor in Comparison with the Adsorption Process
Abstract: Mixed transition-metals oxide electrocatalysts have shown huge potential for electrochemical water oxidation due to their earth abundance, low cost and excellent electrocatalytic activity. Here we present CoFeBO coatings as oxygen evolution catalyst synthesized by Pulsed Laser Deposition (PLD) which provided flexibility to investigate the effect of morphology and structural transformation on the catalytic activity. As an unusual behaviour, nanomorphology of 3D-urchin-like particles assembled with crystallized CoFe2O4 nanowires, acquiring high surface area, displayed inferior performance as compared to coreshell particles with partially crystalline shell containing boron. The best electrochemical activity towards water oxidation in alkaline medium with an overpotential of 315 mV at 10 mA/cm2 along with a Tafel slope of 31.5 mV/dec was recorded with coreshell particle morphology. Systematic comparison with control samples highlighted the role of all the elements, with Co being the active element, boron prevents the complete oxidation of Co to form Co3+ active species (CoOOH), while Fe assists in reducing Co3+ to Co2+ so that these species are regenerated in the successive cycles. Thorough observation of results also indicates that the activity of the active sites play a dominating role in determining the performance of the electrocatalyst over the number of adsorption sites. The synthesized CoFeBO coatings displayed good stability and recyclability thereby showcasing potential for industrial applications. Graphic Abstract: [Figure not available: see fulltext.] 2021, The Author(s). -
An efficient low complexity compression based optimal homomorphic encryption for secure fiber optic communication
Latest advancements in fiber optic communication have gained significant attention among researchers owing to many benefits such as high data rate, acceptable cost, bandwidth, low attenuation, etc. Fiber optic networks are found to be a commonly utilized platform to transfer data in several applications such as personal, commercial, military areas, etc. Although fiber optic networks are highly beneficial, security remains a challenging design issue. Numerous state of art works has been developed to achieve security in fiber optic communication. Among the various methods, compression then encryption is an effective way to effectively and securely transmit the data. With this motivation, this paper presents a new Low Complexity Compression Then Encryption using Optimal Homomorphic Encryption (LCCE-OHE) technique for secured fiber optic communication. The proposed LCCE-OHE technique operates on two major phases namely compression and encryption. At the first stage, low complexity compression using Neighboring Indexing Sequence (NIS) with Deflate algorithm, named Normalized Information Distance (NID) is used. Besides, in the second stage, Quasi Oppositional Sail Fish Optimizer with Homomorphic Encryption (QOSFO-HE) technique is employed. The QOSFO algorithm is derived by incorporating the quasi oppositional learning (QOBL) concept to the SFO algorithm and is applied to optimally select the encryption keys. The performance validation of the proposed model takes place on two benchmark datasets and the experimental results are examined interms of different performance measures. The experimental values highlighted the improved compression efficiency and security level of the LCCE-OHE technique over the other techniques. 2022 Elsevier GmbH -
Transformational Impact of COVID-19 on Savings and Spending Patterns of Indian Rural Households
COVID-19 has spread across the globe at a shocking level and significantly affects the world economy. The pandemic has significantly impacted rural households, the primary workforce for industrialized urban areas, in every sector of rural businesses, including agriculture. Furthermore, the dearth of employment in the primary industry has also adversely influenced rural inhabitants livelihood and financial decisions. COVID-19 changed the perception of people regarding their income and expenditure. This study is intended to analyse the transformation of savings and spending of rural households during COVID-19. A questionnaire was developed using a Likert scale to elicit study variables, and the collected data were analysed using structural equation modelling. The results showed that all types of savings had a positive and significant relationship with the savings motive of rural households during COVID-19. Further, customary and spontaneous spending had a positive and significant relationship spending pattern of rural households. Rural inhabitants were interested in compromising their spending and other forms of savings to have more emergency savings. Earlier studies have examined either the savings or the spending pattern of rural households, and studies on both savings and spending by rural households are very few. The present study thus adds to the existing literature in the field. The Author(s) 2022. -
Being a therapeutic clown- an exploration of their lived experiences and well-being
Therapeutic clowning uses humor and play to minimize the stress for patients and their families during hospitalization. This study aims to explore the subjective meaning of therapeutic clowning through clowns perspective, understand why they continue clowning and interpret how it has impacted them. The research design takes a qualitative approach using phenomenological paradigm. Nine therapeutic clowns between 20 and 60years with clowning experience of 6months-4years from Compassionate Clowns, located at Bangalore were interviewed. The results reflected that the journey of being a therapeutic clown has been equally therapeutic for the clowns. Based on the thematic data analysis network, it was found that clowning has instilled many values in the way they think. It has given them a platform to learn new things from the children they clown. Therefore, looking at these results it could be said that therapeutic clowning serves as a medium for community service and in maintaining personal wellbeing. 2020, Springer Science+Business Media, LLC, part of Springer Nature. -
Oxidation reactions of carbaryl in aqueous solutions
Hydroxyl radical induced oxidation of carbaryl has been studied using steady state photolysis followed by high-resolution mass spectrometry (LC-Q-TOF-MS), pulse radiolysis, and theoretical (DFT) calculations. The reaction of ?OH with carbaryl resulted in a number of hydroxylated adduct radicals (?max - 330 nm and 390 nm; k2 - 1.2 1010 dm3 mol-1 s-1). The DFT calculations and results obtained from LC-Q-TOF-MS analysis shows the possible addition of ?OH at C1 (energetically most stable) and C7 positions of carbaryl leading to the generation of resonance stabilized hydroxycyclohexadienyl-type radicals as the immediate intermediates, which eventually converted into naphthol and a hydroxylated naphthols. LC-Q-TOF-MS results also revealed the formation of other hydroxylated derivatives and naphthoquinones that are most likely originated from the consecutive ?OH attack on the initially formed products. Naphthoquinones are found to undergo ring opening and the corresponding products are identified. The reaction of SO4?- with carbaryl, on the other hand, results the radical cation of parent molecule (?max - 320 nm and 390 nm) which exhibits reasonable stability in the pulse radiolysis timescale. Total organic carbon (TOC) analysis after H2O2/UV photolysis revealed that nearly 70% of the organic content is mineralized after 35 min of irradiation, which demonstrates the potential application of oxidative methods towards the degradation of carbaryl. 2021 Elsevier B.V. -
A new numerical investigation of fractional order susceptible-infected-recovered epidemic model of childhood disease
The susceptible-infected-recovered (SIR) epidemic model of childhood disease is analyzed in the present framework with the help of q-homotopy analysis transform method (q-HATM). The considered model consists the system of three differential equations having fractional derivative, and the non-linear system exemplifies the evolution of childhood disease in a population and its influence on the community with susceptible, infected and recovered compartment. The projected method is a mixture of q-homotopy analysis method and Laplace transform. Two distinct explanatory cases are considered, and corresponding simulations have been demonstrated in terms of plots for different value of the order. The present investigation elucidates that the projected both derivative and technique play a vital role in the analysis and illustrate the behaviour of diverse mathematical models described with differential equations in human disease. 2021 THE AUTHORS -
Desymmetrisation of meso-2,4-Dimethyl-8-oxabicyclo[3.2.1]-oct-6-ene-3-ol and its Application in Natural Product Syntheses
The compounds containing chiral centers and different functional groups serve as magnificent building blocks for the preparation of various natural products that are having immense biological activity. Dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-3-ol is one of the wonderful synthons to construct multiple stereo centers at a time during the asymmetric synthesis. In this account, we discuss our research efforts toward the synthesis of various simple and complex natural products from the past three decades (19952020) by using dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-3-ol as a synthon. Moreover, the synthetic utility of this starting material was investigated and well demonstrated. Further, we executed the desymmetrization of dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-3-ol by hydroboration to get different chiral centers. After obtaining the stereocenters, we could manage either the fragment, formal or total synthesis of natural products, by simple protection and deprotection sequence followed by C?C bond formation steps. 2021 The Chemical Society of Japan & Wiley-VCH GmbH -
Strategically fabricated Ag loaded Fe-g-C3N4 nanosheet for photocatalytic removal of aqueous organic pollutant
The efficiency of the photocatalyst towards the degradation of organic pollutants depends on the harvesting of the visible light and inhibiting the recombination rate of electron-hole pairs to create a large number of charge carriers to drive the redox reaction. Most charge carriers recombine in 2D photocatalyst like g-C3N4 through the bulk process within the stacked layered structure. The recombination through bulk can be suppressed through nanosheet formation, while surface recombination can be inhibited via fast interfacial photogenerated charge transfer. In the present work, Ag-loaded Fe-doped g-C3N4 nanosheet (Ag/Fe-g-C3N4 NS) photocatalyst was synthesized by combining three effective strategies i.e., Fe doping, nanostructuring, and Ag loading. Various analytical techniques have been employed to characterize all the prepared samples. The results indicate that Fe doping influences visible light absorption by modifying the electronic and optical properties. In contrast, nanosheet formation leads to a significant increment in the number of active sites due to the increased surface area. Ag anchoring over Fe-g-C3N4 NS favors charge separation at the interface of Fe-g-C3N4 and Ag due to the presence of the Schottky barrier. Integration of all the three strategies in Ag/Fe-g-C3N4 NS creates a synergistic effect to add beneficial properties and displays a 5-fold improvement in photocatalytic degradation of organic pollutants, as compared to pure g-C3N4. The present study provides a novel and facile approach for realizing an efficient photocatalyst for environmental remediation. 2022 Elsevier B.V. -
Geraniol and Citral as potential therapeutic agents targeting the HSP90 activity: An in silico and experimental approach
Lemongrass essential oil has antifungal and anti-cancerous properties. Heat-shock protein (HSP90), an ATP-dependent molecular chaperone found in eukaryotes, is involved in protein folding, stability, and disease, making it a promising research topic. Both in silico and in vitro approaches were used to provide a clear insight into the HSP90-ATPase 3D structures, activity, and their interaction with the essential oil constituents among various species such as fungi (S. cerevisiae), parasites (P. falciparum), and humans. For in silico studies, sequence alignment, docking (AutoDock), and absorption, distribution, metabolism, and excretion (ADME) properties were evaluated to obtain hit compounds specifically against each HSP90-ATPase. The hit compounds obtained were evaluated for their efficacy in the in vitro studies of S. cerevisiae. In vitro studies were carried out targeting HSP90-ATPases via lemongrass essential oil components individually and in combination as a function of concentration and various salt concentrations. Results suggest that sequence alignment exists of over 75% among these three species. The best docking score was possessed by Geraniol and its constituent (geldanamycin ? ?4.93 kcal/mol) (a known antifungal and antitumor against HSP90) in all the above species. Lemongrass oil and the combination of Geraniol and Citral at concentrations of 80 ?g/mL showed the maximum inhibition of ATPase and HSP90-ATPase activity compared to their individual treatment. Therefore, both in silico and in vitro studies provide clear evidence of specific inhibitory action of lemongrass oil, Geraniol, and Citral against the ATPase and HSP90ATPase activities and might show potential as antifungal and antitumor drugs. 2021 -
Challenges to state control of territory: Comparative analysis of Yemen, Afghanistan and Myanmar
States around the world have lost control over their territory to armed non-state actors, including states like Yemen, Afghanistan and Myanmar in the Asian region. This article aims to understand why these states are unable to exercise control over all of their territory. The study identifies and examines four major challenges faced by states in maintaining control over their territory lack of state legitimacy and effectiveness, strategic motives of armed non-state actors, socio-economic motives of armed non-state actors and external intervention. A comparative analysis of the cases of Yemen, Afghanistan and Myanmar illustrates the wide relevance of these challenges faced by the states with respect to territorial control. The Author(s) 2021. -
Friction Stir Welding of Dissimilar Aluminium Alloys for Vehicle Structures
Welding process in vehicle structures has gained importance, especially for better strength and mechanical properties. Hence, there is vast research going on in the domain of newer welding techniques. Friction Stir Welding (FSW) is one of them. FSW is used in this research to join two different grades of aluminium alloys by varying the process parameters. The process parameters are optimized based on the Design of Experiments (DoE) and the Taguchi techniques. From the experimental findings for different process parameters, the optimized set of conditions involving the normal, transverse forces and the torque are determined. Further, the process methodology is validated. 2022, MechAero Found. for Techn. Res. and Educ. Excellence. All rights reserved. -
Corrosion behavior of AlCuFeMn alloy in aqueous sodium chloride solution
Medium Entropy Alloy AlCuFeMn possesses high room temperature strength and oxidation endurance. In present work, the aqueous corrosion resistance of the as-cast as well as low temperature oxidized AlCuFeMn alloy in 3.5 wt% NaCl solution, is explored. Equimolar proportions of high purity copper, manganese, iron, and aluminum were arc melted and cast in a copper mold. The alloy primarily consists of a face-centered cubic and a body-centered cubic phase. Potentiodynamic polarization tests on the alloy after low temperature surface oxidation reveal an aqueous corrosion resistance comparable to AISI 304 steel and CoCrFeMnNi high entropy alloy. The X-ray photoelectron spectroscopic studies confirmed that the free surface in the as-cast alloy is in partially oxidized state. The same completely oxidizes after low-temperature surface oxidation. Such low temperature surface oxidation improves pitting corrosion resistance in AlCuFeMn alloy due to increased metal/oxide layer resistance. The electrochemical impedance spectroscopy tests coupled with microscopy confirmed that the principal corrosion mechanisms in the alloy are of the uniform and pitting type. The energy dispersive spectroscopy experiments indicate that a copper oxide enriched layer is formed on the surface oxidized specimen during corrosion. 2021 Elsevier B.V. -
THE VICIOUS LOOP OF BODY SHAMING AND SELF-PROJECTION: AN EXPLORATIVE STUDY OF INDIAN YOUNG PEOPLE AGED 20-30 YEARS OLD
Background: Body shaming leads to much insecurity that is often overlooked. Its impact results in many ways, either in the form of some mental disorder, non-acceptance of oneself, low self-esteem, decreased life satisfaction, etc. The Media adds to it by portraying perceived perfectionism in terms of appearance which at times acts as a trigger to people already suffering or going through these. Purpose: The purpose of the study was to explore the psychological effects of body shaming on young people, and to analyze the role and impact of media in the portrayal of body image issues. Design/Methodology/Approach: A Semi-structured interview of 20 participants was carried forward (10 males & 10 females belonging). All Participants belonged to the age bracket of 20-30 years. Interpretative Phenomenological Analysis was conducted thereafter. Findings: All the participants mentioned that body shaming has affected their well-being and self-esteem and it led them to body shame others as well. It was also found that media has been marketing body image issues in many ways which created both positive and negative impacts. The following themes were generated based on analysis: age-appropriate body, rituals to fit in, marketing by accepting, after effects, the vicious loop, confusion to/and acceptance. Conclusion: The psychological impact of body shaming is often overlooked and that creates more damage. Similarly, the marketing of body image issues is so popular that often it is used in the form of humour. All of these experiences create a deep impact on people and lead them to the vicious loop of body shaming. 2022, RJ4All Publications. All rights reserved. -
Role of digital technologies to combat COVID-19 pandemic
Purpose: The unexpected epidemic of the latest coronavirus in 2019, known as COVID-19 by the Globe, a number of governments worldwide have been put in a vulnerable situation by the World Health Organization. The effect of the COVID-19 outbreak, previously experienced by Chinas citizens alone, has now become more pronounced. For practically every nation in the world, this is a matter of grave concern. The lack of assets to withstand the infection of COVID-19, mixed with the perception of overwhelmed medical mechanisms, pressured a number of places in a state of partial or absolute lockdown. Design/methodology/approach: The medical photos such as computed tomography (CT) and X-ray playa key role in the worldwide battle against COVID-19, while artificial intelligence (AI) has recently appeared. The power of imaging is further increased by technology tools and support for medical specialists. In comparison to the related direct health effects because of the COVID-19 disaster, this research identifies its impacts on the overall society. Findings: This paper hereby examines the rapid answers in the medical imaging community toward COVID-19 (empowered by AI). For example, the acquisition of AI-empowered images will significantly assist automate the scanning process and reshape the procedure as well. AI, too, may improve the quality of the job by correctly delineating X-ray and CT image infections, promoting subsequent infections, quantification. In addition, computer-aided platforms support radiologists make medical choices, i.e. for illness tracking, diagnosis and prognosis. Originality/value: This research encompasses the whole medical imaging pipeline and methods for research related to COVID-19, include a collection of images, segmentation, diagnosis and monitoring. In drawing stuff to minimize the effects of the COVID-19 epidemic, this paper is investigating the use of technologies such as the internet of things, unmanned aerial vehicles, blockchain, AI, big data and 5G. 2021, Emerald Publishing Limited. -
Heat transport in the flow of magnetized nanofluid over a stretchable surface with heat sources: A mathematical model with realistic conditions
Analyzing the heat transport of nanofluids is of prime importance to various industrial and engineering sectors which involves modeling the physical phenomena via highly nonlinear partial differential equations. In this study, the flow and heat transport of a nanoliquid on a bi-directionally elongating surface subject to two different heat modulations (linear temperature-related heat source and space-related exponential heat source) is investigated using the two-component Buongiorno nanoliquid model. The dynamics of the nanoliquid are altered by an external magnetic field applied perpendicular to the sheet. The impact of Brownian motion, Lorentz forces, and thermophoresis are analyzed under the realistic passive control of the nanoparticles. A comparative analysis of the flow over the linear and nonlinear drawn surface is presented. Numeric solutions for the governing partial differential system are obtained through the finite difference method (FDM). Among two types of heat source modulations, the maximum heat transport is observed in the presence of the exponential space-based heat source modulation. The flow and thermal fields are found to advance in the linear elongated surface flow than the nonlinear elongated flow. Furthermore, the random movement of the nanoparticles and the greater magnitude of the Lorentz force have a positive effect on the thermal enhancement in the nanoliquid system. The results of the study have applications in heating/cooling processes, nanoliquid-dependent structures, and thermal systems with stretchable materials. 2021 Wiley-VCH GmbH -
Toxicological Profiling of Onion-Peel-Derived Mesoporous Carbon Nanospheres Using In Vivo Drosophila melanogaster Model
Toxicological profiling of the novel carbon materials has become imperative, owing to their wide applicability and potential health risks on exposure. In the current study, the toxicity of mesoporous carbon nanospheres synthesized from waste onion peel was investigated using the genetic animal model Drosophila melanogaster. The survival assays at different doses of carbon nanoparticles suggested their non-toxic effect for exposure for 25 days. Developmental and behavioral defects were not observed. The biochemical and metabolic parameters, such as total antioxidant capacity (TAC), protein level, triglyceride level, and glucose, were not significantly altered. The neurological toxicity as analyzed using acetylcholinesterase activity was also not altered significantly. Survival, behavior, and biochemical assays suggested that oral feeding of mesoporous carbon nanoparticles for 25 days did not elicit any significant toxicity effect in Drosophila melanogaster. Thus, mesoporous carbon nanoparticles synthesized from waste onion peel can be used as beneficial drug carriers in different disease models. 2022 by the authors. Licensee MDPI, Basel, Switzerland. -
Convective heat and mass transports and chaos in two-component systems: comparison of results of physically realistic boundary conditions with those of artificial ones
Linear and weakly nonlinear stability analyses of double-diffusive convection in two-component liquids with either potassium chloride (KCl) or sodium chloride (NaCl) aqueous solution, and heat being present is investigated in the paper for free, and rigid, isothermal, iso-solutal boundaries. Using the thermophysical values of the aqueous solutions, we have shown that the stationary convection is the preferred mode at onset and that sub-critical motion is possible. We found that the critical thermal Rayleigh number for water+NaCl+heat is higher compared to that of water+KCl+heat. The study shows that for water+KCl+heat, the transition from convective motion to chaotic motion occurs at rH= 27.2 for free boundaries and at 48.5 for rigid boundaries. Here, rH denotes the Hopf thermal Rayleigh number. Further, the existence of windows of mildly chaotic points and fully periodic intervals are reported using Lyapunov exponents and bifurcation diagrams. Chaotic motions in both the aqueous solutions are nearly identical. The percentage increase in heat transport in the double-diffusive system involving NaCl is nearly 1% more than that of KCl in the case of free boundaries, whereas in the case of realistic boundaries it is nearly 1.6%. The comparison of the Nusselt and the Sherwood numbers between water+KCl and water+NaCl leads us to the conclusion that the aqueous solution with lower Lewis number transports maximum heat in the case of free boundaries and opposite is seen in the case of rigid boundaries due to the boundary effect. The many qualitative similarities between the results of artificial and realistic boundaries are highlighted. 2021, Akadiai Kiad Budapest, Hungary. -
REGARDING NEW NUMERICAL RESULTS for the DYNAMICAL MODEL of ROMANTIC RELATIONSHIPS with FRACTIONAL DERIVATIVE
The main purpose of the present investigation is to find the solution of fractional coupled equations describing the romantic relationships using q-homotopy analysis transform method (q-HATM). The considered scheme is a unification of q-homotopy analysis technique with Laplace transform (LT). More preciously, we scrutinized the behavior of the obtained solution for the considered model with fractional-order, in order to elucidate the effectiveness of the proposed algorithm. Further, for the different fractional-order and parameters offered by the considered method, the physical natures have been apprehended. The obtained consequences evidence that the proposed method is very effective and highly methodical to study and examine the nature and its corresponding consequences of the system of fractional order differential equations describing the real word problems. 2022 The Author(s). -
Spectral Properties of the Soft X-Ray Transient MAXI J0637-430 Using AstroSat
Soft X-ray transients are systems that are detected when they go into an outburst, wherein their X-ray luminosity increases by several orders of magnitude. These outbursts are markers of the poorly understood change in the spectral state of these systems from the low/hard state to the high/soft state. We report the spectral properties of one such soft X-ray transient: MAXI J0637-430, with data from the SXT and LAXPC instruments on board the AstroSat mission. The source was observed for a total of ?60 ks in two observations on 2019 November 8 and 21 soon after its discovery. Flux-resolved spectral analysis of the source indicates the presence of a multicolor blackbody component arising from the accretion disk and a thermal Comptonization component. The stable low temperature (?0.55 keV) of the blackbody component points to a cool accretion disk with an inner disk radius of the order of a few hundred kilometers. In addition, we report the presence of a relativistically broadened Gaussian line at 6.4 keV. The disk-dominated flux and photon power-law index of ?2 and a constant inner disk radius indicate the source to be in the soft state. From the study we conclude that MAXI J0637-430 is a strong candidate for a black hole X-ray binary. 2022. The Author(s). Published by the American Astronomical Society.