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Photocatalytic degradation of methylene blue and metanil yellow dyes using green synthesized zinc oxide (Zno) nanocrystals
In this work, ZnO nanocrystals (NCs) have been effectively synthesized by a simple, efficient and cost-effective method using coconut husk extract as a novel fuel. The synthesized NCs are characterized by UV-Vis, XRD, FT-IR, SEM, EDX, Raman and PL studies. The obtained ZnO were found to be UV-active with a bandgap of 2.93 eV. The X-ray diffraction pattern confirms the crystallinity of the ZnO with hexagonally structured ZnO with a crystallite size of 48 nm, while the SEM analysis reveals the hexagonal bipyramid morphology. Photocatalytic activities of the synthesized ZnO NCs are used to degrade methylene blue and metanil yellow dyes. 2021 by the authors. Licensee MDPI, Basel, Switzerland. -
Energy Efficient Evolutionary Algorithm based Clustering with Route Selection Protocol for IoT Assisted Wireless Sensor Networks
Internet of Things (IoT) assisted wireless sensor network (WSN) finds its applicability in several real-time tracking and surveillance applications. However, it suffers from various issues such as restricted battery capacity, repeated interruptions owing to multi-hop data transmission, and limited communication range. Gathering and multihop directing are considered effective solutions to complete enhanced energy competence and a generation of IoT-assisted WSN. An NP-hard problematic that can be handled with an evolutionary algorithm is the collection of the cluster head (CH) and the best potential paths to the goal. Both of these problems involve finding the optimum route to the target (EA). In this context, this study presents the design of the Energy Efficient Evolutionary Algorithm-based Clustering with Route Selection (EEEA-CRS) Protocol for Internet of Things-Assisted Wireless Sensor Networks (IoT-Assisted WSN). The EEEA-CRS technique that has been proposed has the primary intention of enhancing the energy efficiency as well as the lifetime of the IoT-assisted WSN. The EEEA-CRS approach that has been presented is broken down into its basic parts, which are the Fuzzy Chicken Swarm Optimization based Clustering (FCSO-C) phase and the Biogeography Optimization-based Multihop Routing phase (BBO-MHR). The FCSO-C technique that has been suggested chooses CHs with the use of a fitness function that takes into account residual energy, inter-cluster distance, and intra-cluster detachment. In adding, the BBO-MHR strategy identifies the optimum pathways to BS by taking into account the costs of communicating with other clusters, both within and between them. A number of different simulations were carried out in order to demonstrate that the EEEA-CRS methodology yields superior results. The EEEA-CRS method was shown to be superior to other methods in use today, according to the findings of an exhaustive comparison and study. EverScience Publications. -
Banana peels as a cost effective substrate for fungal chitosan synthesis: optimisation and characterisation
Massive accumulation of unprocessed banana peels enthralls sustainable issues as they are eventually dumped as landfills leading to emission of obnoxious gasses. To avoid these persisting challenges the present study shims lights on chitosan production from the characterised fungal strain using banana peel hydrolysate as an effective medium. Substantial amount of carbohydrate in banana peels serves as a potential solution for fungal chitosan production in a view to attain a circular bioeconomy and repurposed for synthesis of beneficial products in a cost effective manner. Presence of fermentable sugars in banana peels qualifies them as a feasible substrate which could be exploited for scaling up of fungal chitosan synthesis. Screened isolate was subjected to statistical optimisation using formulated medium to elucidate the influential factors that had significant effect on chitosan production. The harvested chitosan biomass was characterised through standardised techniques and evaluated for further studies. Statistical optimisation reveals that ammonium nitrate (5 g/L), pH (6) and incubation time (144 hrs) were the three PBD variables that had a greater influence on fungal chitosan yield. The validated developed model exhibited maximum yield of 200 mg/L, a 4.4 fold increase than unoptimised medium (45 mg/L). These findings emphasise the fermentative synthesis of chitosan through valorisation of banana peel prop up a complementary approach in concomitant with preserving renewable resources and bioproduct formation. 2023 Informa UK Limited, trading as Taylor & Francis Group. -
Distillery effluent valorization through cost effective production of polyhydroxyalkanoate: optimization and characterization
The devastating effect of fossil plastics in the biosphere has tuned the concern for bioplastic production in the last few decades. Polyhydroxyalkanoate, a biopolyester, has a wide range of applications as they impose positive societal impact by being biodegradable and void of any ill-effects when used in vivo. Despite their eco-friendly nature, the outreach of PHA is bounded in industrial scale as the overall expense is highly comparable to conventional plastics. Therefore, in an attempt to attain a feasible production, the present study aims at utilizing raw distillery effluent for PHA production using Bacillus subtilis NCDC 0671. Different dilutions of spent wash (5%, 10%, 15%, and 20%) were assessed for PHA production in the modified medium among which 10% showed maximum PHA accumulation. Furthermore, statistical optimization by response surface methodology enhanced PHA synthesis to 6.3g/L which is 3.3-fold increases. FTIR and NMR characterization of the biopolymer from the optimized medium was similar to the previous literature which provides a promising approach for cost effective production. 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Polyhydroxyalkanoate biosynthesis and characterization from optimized medium utilizing distillery effluent using Bacillus endophyticus MTCC 9021: a statistical approach
Use of expensive raw material and inefficient extraction method has limited the production of biopolymers at pilot scale compared to commercial plastics. Hence, this research work spotlights on production of polyhydroxyalkanoate (PHA) using Bacillus endophyticus MTCC 9021 in different dilutions of untreated distillery effluent (1025%) among which 10% dilutions exhibited maximum PHA production. Statistical optimization through Response surface methodology yielded a maximum PHA of 6.45 0.07 g/L. The obtained PHA was analysed by FTIR and NMR which confirms the polymer to be polyhydroxybutyrate. The extracted PHA was reduced to nanoscale to develop PHA nanosheet which exposed higher oil absorption and retention ability than normal PHA sheet. Further the rapid degradation of PHA nanosheet with synthetic plastics in garden soil emphasises their unique application in wide sectors. 2020, 2020 Informa UK Limited, trading as Taylor & Francis Group. -
Defiance in the Shadows: Flames of Resilience in the Selected North Korean Memoirs
The resilient autobiography focuses on the interpersonal dynamics of life narratives, including the relationships that have exacerbated the hardships described and the ones that have provided the support and strength necessary to overcome them. The selected text for this paper is A Thousand Miles to Freedom: My Escape from North Korea by Eunsun Kim and Sebastien Falletti and In Order to Live: A North Korean Girls Journey to Freedom by Yeonmi Park and Maryanne Vollers. These two texts talk about their catastrophic journey from North Korea because of poverty caused by famine and their migration to China, where they were trafficked and subjected to humiliation and their final escape to South Korea. The memoirs depict the individual?s embodiment of resilience as they narrate their own struggles and victories in overcoming hardship. Resistance to adversity and suffering, as well as the ability to bounce back from painful experiences in one?s own life and in the lives of others, are the hallmarks of resilience. Trauma becomes ingrained in attempts for survival in both memoirs, which illustrate the catastrophic impacts of famine, relocation, and personal loss. One effective approach to enhance resilience is reorganizing and reestablishing control over one's life after a traumatic event. Interpretations and writings of the personal narrative are offered from both the subject?s and an outsider?s points of view. Thus, the life story is formed in a dual sense: autobiographically and biographically. 2024 Sciedu Press. All rights reserved. -
Organic produce and millennials: Motives, attitudes and purchase intention
In this paper, we focus and discuss the factors, which motivates and influence consumer behavior towards organic produce. We extract findings from the Bengaluru city and target population of the study is the millennials i.epeople who belongs to the age group of 23-38. The shift in the attitude and preference of the modern consumers is greatly influenced by the proliferation of various health problems. This study provides a framework for organic industry to understand consumers demand and preferences and provides a perspective of Indian organic produce industry from consumers perspective which might serve as a basis for the future development of organic produce market. 2019 SERSC. -
Convergence of retail banking interest rates to households in euro area: Time-varying measurement and determinants /
International Economics and Economic Policy, Vol.17, Issue 1, pp.25-65 -
Asymmetric dynamic conditional copula correlation and fundamental determinants of interest rate comovement /
Journal of Economic Integration, Vol.34, Issue 4, pp.667-704, ISSN No: 1225-651X. -
Polyoxometalate/?-Fe2O3/polyaniline composite: Tailored approaches for high-performance supercapacitors
The need for portable, high-performance electronics that have high power or energy density has increased significantly in recent years. In this work, a composite material was coated on stainless steel that consists of polyoxometalate (POM)/?-Fe2O3/polyaniline (PANI) as an electrode material for a symmetric supercapacitor. ?-Fe2O3 was prepared using starch as a template while PANI was electrodeposited. The physical and chemical characteristics of the modified electrodes were investigated via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and electrochemical techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge[sbnd]discharge (GCD) experiments. In 1 M H2SO4, the composite had a specific capacitance of 528 F/g at a current density of 0.2 A/g. In addition, the composite exhibited a high energy density of 73.4 Wh kg?1 at a high-power density of 7.14 kW kg?1 and 91.62 % capacity retention after 10 cycles. The results show that POM/?-Fe2O3/PANI is a promising composite electrode for use as a supercapacitor electrode material. 2024 The Authors -
Competitive and contagion effect of initial public offerings in India: An empirical study
This study aims to empirically examine the impact of initial public offerings (IPOs) on the equity share prices of industry rivals. The cross-industry sample comprises 13 companies across six different industries in the Indian market. The study investigates four key variables: the stock returns of industry rivals before and after the IPO of a new market entrant, as well as the daily traded volume of both the market entrant and industry rivals in the days following the IPO. The analysis reveals a significant association between the stock prices of industry rivals before and after the listing date of a market entrant, as evidenced by the adoption of three distinct time windows. However, no significant relationship is observed between the daily traded volume of market entrants and industry rivals. The results reveal the presence of the competitive and contagion effect and the lack of active capitalisation of this short-term phenomenon by investors. 2023 The Author -
Theoretical analysis of the thermal characteristics of ReeEyring nanofluid flowing past a stretching sheet due to bioconvection
This analysis examines the flow of ReeEyring nanofluid over a stretching sheet in the presence of an inclined magnetic field. The nanoparticle distribution in the nanofluid is stabilised by the movement of motile microorganisms and it constitutes bioconvection. Meanwhile, the impact of thermophoresis and Brownian motion which plays an important role in the transfer of heat and mass is considered along with the convective boundary conditions. The flow of non-Newtonian nanofluid is widely used in the many manufacturing industries as a major component of cooling. Furthermore, it finds applications in thermal extrusion systems, biomedical engineering, cancer treatment etc. The governing equations are formulated using partial differential equations that are translated into non-linear differential equations employing appropriate relations based on these assumptions. The differential transformation technique (DTM) is used to solve these non-linear differential equations, and the results are shown in graphs and tables for various fluid flow parameters. The skin friction coefficient, local Nusselt, and motile density are all calculated and examined numerically. Fluid velocity is observed to increase as a function of a fluid variable. Furthermore, increasing the value of the thermal and relaxation solutal parameters reduces the temperature and concentration. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2022. -
Nanofluid flowing over a rotating disk that is stretching and permeable: An unsteady model
The model presented in this paper deals with the investigation of the unsteady laminar flow past a stretchable disk. The nanofluids Al2O3/H2O and Cu/H2O are considered for the analysis where the thermal characteristics and flow behavior of these nanofluids are compared. In addition, the system is subjected to the suction force that has significant impacts on velocity of the nanofluid flow. Further, the nanoparticle solid volume fraction is another important parameter that is discussed which has a prominent role on both profiles of the nanofluid. Furthermore, the investigated mathematical model is framed using PDEs that are transformed to ODEs using suitable transformations. The system of equations obtained in this regard is solved by employing the RKF-45 numerical method where the results are obtained in the form of graphs. Various nanofluids flow parameters arise in the study and the impact of all these parameters has been analyzed and interpreted. Some of the major outcomes are that the higher values of nanoparticle solid volume fraction enhance the temperature while it decreases velocity of the flow. The comparison of flow of the two nanofluids concluded that aluminawater nanofluid has a better velocity while the copperwater nanofluid has a better thermal conductivity. World Scientific Publishing Company. -
Corrigendum to Implementation of modified Buongiorno's model for the investigation of chemically reacting rGO-Fe3O4-TiO2-H2O ternary nanofluid jet flow in the presence of bio-active mixers [Chemical Physics Letters, 786, 2022, 139194]
A few typographical errors have been identified in our paper titled Implementation of modified Buongiorno's model for the investigation of chemically reacting rGO-Fe3O4-TiO2-H2O ternary nanofluid jet flow in the presence of bio-active mixers. This corrigendum addresses those errors however, these errors have no impact on the obtained results. 2022 -
Quadratic convection on the radiative flow of ternary nanofluid Gr-Ag-TiO2-H2O subjected to velocity slip and temperature jump
This paper deals with the analysis of the flow and heat transfer performance of ternary nanofluid flowing past a stretching sheet under the influence of quadratic convection. The ternary nanofluid is formed by suspending three dierent nanoparticles, namely, titanium dioxide (TiO2), silver (Ag) and graphene (Gr) in the base fluid water (H2O). Thus, the ternary nanofluid obtained is Gr-Ag-TiO2/H2O where the hybrid nanofluid Ag-TiO2/H2O forms the base fluid for the resulting ternary nanofluid. The addition of TiO2 nanoparticles enhances the photocatalytic nature of the base fluid and makes it useful in various applications concerning the medicinal field. The presence of Gr helps in intensifying the thermal conductivity of water while the suspension of silver nanoparticles ensures chemical stability. Meanwhile, the thermophysical properties of the ternary nanofluid are mathematically defined and the system of equations that describe the flow of a ternary nanofluid past a stretching sheet is framed using dierential equations. The outcomes of this study are interpreted through graphs for velocity and temperature profiles of the ternary nanofluid. It was mainly observed that the thermal conductance of ternary nanofluid was higher than the monophase and hybrid nanofluid. Also, the presence of quadratic convection had a prominent impact on the ternary nanofluid flow. The Nusselt number was found to be greater for spherical nanoparticles and it was found to be least for blade-shaped nanoparticles. 2024 World Scientific. All rights reserved. -
Bioconvective DarcyFrochherimer flow of the ReeEyring nanofluid through a stretching sheet with velocity and thermal slips
In the current study, the bioconvective flow of ReeEyring through an expanding sheet with the porous medium is analyzed by considering the inclined magnetic field and gyrotactic microorganisms. Buongiorno's model, which defines the two major mechanisms; thermophoresis and Brownian motion is used to frame the mathematical model. The presence of motile cells helps in stabilizing the nanoparticle and avoids the sedimentation due to nanoparticles. The mathematical model with these assumptions is framed using partial differential equations (PDE) that are later remodeled to ordinary nonlinear differential equations by incorporating desirable similarity transformation. The equations so obtained shall be solved using DTM and the outcomes are described through graphs and tables. The graphs indicated that the velocity of the nanofluid flow reduces with the increase in the porosity and similarly, the higher values of Peclet number (Pe) are found to diminish the motile density. Whereas the increase in the thermophoresis parameter enhances the thermal and mass profiles of the nanofluid. 2022 Informa UK Limited, trading as Taylor & Francis Group. -
The analogy of nanoparticle shapes on the theory of convective heat transfer of AuFe3O4 Casson hybrid nanofluid
In recent times, Au nanoparticles have beencommonly used for delivering the drug especially in the case of hypothermia of tumors, but low absorption of IR light does not solve destruction of tumor cells. However, nanoparticles such as Fe3O4 coated with Au could be used to deliver the drug to a specific spot due to applied external magnetic field. Due to these applications, boundary layer approximation is invoked to simplify the mathematical model. This paper presents the nanoparticle shape analysis and heat transfer features of the AuFe3O4blood hybrid nanofluid flowing past a stretching surface on a magnetohydrodynamic medium. Numerical solutions of nonlinear differential equations are obtained by RKF-45 method with the help of shooting technique. The behavior of emerging parameters is described graphically for velocity and temperature profiles. It is found that the blade-shaped Au and Fe3O4 nanoparticles have better thermal conductance than brick, sphere, cylinder, needle, and platelet shapes. It is also observed that the Lorentz force generated due to magnetic field helps in controlling the flow and enhance the thermal conductivity of hybrid nanofluid. 2021 Wiley Periodicals LLC. -
The convective heat transfer analysis of the casson nanofluid jet flow under the influence of the movement of gyrotactic microorganisms
Jet flows provide an effective mode of energy transfer or mass transfer in industrial applications. When compared to traditional cooling through convection, jet flows have high heat and mass transfer coefficients. Further, the devices equipped with jet flow provides efficient use of fluid and also offers enhanced heat and mass transfer rates. Hence in this study, the jet flow of Casson nanofluid containing gyrotactic microorganisms that stabilises the nanoparticle suspension is discussed. To control the fluid from outside external magnetic field is imposed. The model with these characteristics are useful in the appliances like coolants in automobiles, nuclear reactors, micro-manufacturing, metallurgical process etc. Such a model is created by employing PDE, which are then transformed into a system of ODE. The DTM is employed to obtain the solution to system of equations, and the results are interpreted using graphs. It is perceived that the velocity of the nanofluid flow is decreased because of the increased yield stress created by the greater values of the Casson parameter. As a result, the temperature profile is found to be increasing. Meanwhile, it is observed that for increased value of chemical reaction parameter diminishes the nanoparticle concentration. The motile density is found to decrease for increase in the Peclet number and the bioconvection Schmidt number. Further, the thermophoresis improves the temperature and concentration profile of the nanofluid. 2022 Indian Chemical Society -
The impact of the movement of the gyrotactic microorganisms on the heat and mass transfer characteristics of Casson nanofluid
This article focuses on analyzing the impact of the movement of gyrotactic microorganisms on the heat and mass transfer characteristics of Casson nanofluid flowing between divergent. Further, the analysis is performed through simulation to have a better understanding of the impact. Since the microorganisms are self-propelled, they move on their own in the nanofluid due to the concentration gradient and stabilize the nanoparticle suspension. This movement of microorganisms constitutes the formation of bioconvection. Further, the random motion of nanoparticles gives rise to two major slip mechanisms termed thermophoresis and Brownian motion. The mathematical model comprising these effects is designed using partial differential equations that are converted to ordinary differential equations with the help of suitable similarity transformation. The resulting system of equations is then solved using the differential transformation method and the outcomes are interpreted through graphs. It is indicated that the nanoparticle concentration and the motile density profiles increase with the increase in Schmidt number and also, the concentration profile is found to be increasing for higher Brownian motion parameter and lower thermophoretic parameter. The simulations performed through the finite element method portrayed that the heat flow in the diverging channel is occurring along the isothermal planes. 2022 Informa UK Limited, trading as Taylor & Francis Group. -
Stratified Bioconvective Jet Flow of Williamson Nanofluid in Porous Medium in the Presence of Arrhenius Activation Energy
Due to the higher coefficients of heat and mass transfer, the jet flow has become an effective source for the transfer of heat and mass in various industries. Due to these high coefficients, the heat and mass transfer rates will be high in the appliances equipped with the jet flow. Further, the existence of the magnetic field helps in controlling the velocity and the presence of the gyrotactic microorganisms ensure proper mixing of nanoparticles. A dilute nanoparticle suspension is assumed so that it will not affect the movement of motile cells that leads to bioconvection. Hence, this paper aims to analyze the characteristics of heat transfer as well as mass transfer of the jet flow of Williamson nanofluid past a porous stretching sheet in the existence of microorganisms. The mathematical model obtained as a result of these assumptions is transformed into nonlinear ordinary differential equations for which acceptable solutions are obtained using the numerical method. The results thus obtained are presented graphically and based on the outcomes, it is perceived that the magnetic field has control over the velocity profile thus influencing the thermal profile. The increase in the Williamson parameter also reduces the velocity of the fluid flow. Further, an increase was noticed in the thermal and concentration profiles of the nanofluid for higher values of thermophoresis parameter and the increase in the porosity reduced the speed of the flow of nanofluid. 2023 World Scientific Publishing Company.