Showing papers by "Kuvempu University published in 2017"
TL;DR: In this article, the authors considered the Marangoni transport of dissipating SWCNT and MWCNT nanofluids under the influence of magnetic force and radiation, and derived numerical solutions of the arising nonlinear problem via Runge-Kutta based shooting approach.
Abstract: Present study addresses the Marangoni transport of dissipating SWCNT and MWCNT nanofluids under the influence of magnetic force and radiation. A novel exponential space dependent heat source is considered. The flow is generated due to a disk with surface tension created by thermal gradient. The partial differential equations system governing the flow of carbon-water nanoliquids and heat transfer through Marangoni convection is established. Subsequent system is reduced to nonlinear ordinary boundary value problem via generalized Karman transformations. Numerical solutions are developed of the arising nonlinear problem via Runge-Kutta based shooting approach. Impacts of embedded parameters are focused on Nusselt number , velocity and heat transport distributions through graphical illustrations. Our simulations figured out that the heat transfer rate increased via Marangoni convection; however it is decayed by applied magnetic force. The temperature of SWCNT-H 2O nanoliquid dominates MWCNT-H2O nanoliquid.
105 citations
TL;DR: In this paper, an incompressible electrically conducting Eyring-Powell fluid filled the convectively heated stretching surface in the presence of nanoparticles and the effects of thermal radiation, viscous dissipation and Joule heating were accounted in heat transfer equation.
90 citations
TL;DR: In this article, the authors explored the discussion on combined effects of Joule heating and viscous dissipation on a three-dimensional flow of Oldroyd B nanofluid.
Abstract: Present study explores the discussion on combined effects of Joule heating and viscous dissipation on a three-dimensional flow of Oldroyd B nanofluid. The model describes that flow is generated by bidirectional stretching sheet with thermophoresis and Brownian motion effects and also energy equation contain radiation term. Converted self similar equations are solved via shooting algorithm with RKF 45 method. The influences of Joule heating and viscous dissipation are discussed through graphs. It is noticed that combination of Joule and viscous heating, the temperature of Oldroyd B nanofluid profile increases.
86 citations
TL;DR: The results indicate that Leea indica was a promising antioxidant and anticancer agent for DU-145 and PC-3 human prostate cancer cell lines, however, further studies are needed to conclude its therapeutic use.
Abstract: Background To determine the phytochemical constituents, antioxidant, and anticancer activities of Leea indica leaf extracts on DU-145 and PC-3 human prostate cancer cell lines. Methods Leaf sample was subjected to Soxhlet extraction method with increasing polarity of solvents, namely, chloroform, ethyl acetate, methanol, ethanol, and aqueous. Phytochemical screening was done using different biochemical tests. Quantitative analysis for phenol was determined by Folin–Ciocalteu reagent method. The antioxidant activity was tested using 2,2-diphenyl-1-picrylhydrazyl, ferric ion reducing power assay, and phosphomolybdenum assay. In vitro anticancer activity on DU-145 and PC-3 human prostate cancer cell lines was evaluated by (3-(4, 5-dimethyl thiazole-2yl)-2, 5-diphenyl tetrazolium bromide) MTT assay. Results Phytochemical screening confirmed the presence of phyto-constituents like alkaloids, flavonoids, glycosides, phenols, lignins, saponins, sterols, tannins, anthraquinone, and reducing sugar. Methanol and ethanol extracts exhibited higher phenolic content as compare to aqueous extract. Antioxidant capacities were shown highest in methanol and ethanol extracts based on the test performed. The methanol and ethanol leaf extracts were found to be selectively cytotoxic in vitro to (DU-145 and PC-3) prostate cancer cell lines with IC 50 values 529.44±42.07μg/mL and 677.11±37.01μg/mL for DU-145 and 547.55±33.52μg/mL and 631.99±50.24μg/mL for PC-3 respectively, while it had no cytotoxic effect on normal mice embryo fibroblast cells. Conclusion The results indicate that Leea indica was a promising antioxidant and anticancer agent for DU-145 and PC-3 human prostate cancer cell lines. However, further studies are needed to conclude its therapeutic use.
78 citations
TL;DR: In this paper, the combined effects of nonlinear thermal convection and radiation in 3D boundary layer flow of non-Newtonian nanofluid are scrutinized numerically.
Abstract: The combined effects of nonlinear thermal convection and radiation in 3D boundary layer flow of non-Newtonian nanofluid are scrutinized numerically. The flow is induced by the stretching of a flat plate in two lateral directions. The mechanism of heat and mass transport under thermophoretic and Brownian motion is elaborated via implementation of the thermal convective condition. The prevailing two-point nonlinear boundary value problem is reduced to a two-point ordinary differential problem by employing suitable similarity transformations. The solutions are computed by the implementation of homotopic scheme. At the end, a comprehensive parametric study has been conducted to analyze the typical trend of the solutions. It is found that the nanoparticle volume fraction and temperature profiles are stronger for the case of solar radiation in comparison with problem without radiation.
74 citations
TL;DR: In this paper, a series of Sm substituted zinc spinel ferrite nanoparticles (ZnSm x Fe 2-x O 4 ) were fabricated by co-precipitation method.
Abstract: In this article, a series of Sm substituted zinc spinel ferrite nanoparticles (ZnSm x Fe 2-x O 4 ) were fabricated by co-precipitation method. The effect of samarium substitution and annealing temperature on the crystal structure of zinc ferrite were explored in this study. The lattice parameter and crystallite size are increased with the increase in the Sm content. The visible light absorption ability extended as Sm content was increased up to (x = 1.5) and, which was the best optimal dosage for photocatalytic degradation of Methyl Orange (MO). This red shift in absorbance unequivocally indicates them as potential agent in solar light driven photocatalytic activity. Such enhancement can be ascribed to the diminution in the band gap of zinc ferrite upon samarium substitution (1.42 eV). Present study provides an excellent competency of rare earth substituted ferrite as a new class of photocatalyst over dye degradation under solar light irradiation.
67 citations
TL;DR: In this article, a suitable set of similarity transformations are implemented to reduce the governing partial differential equations into coupled nonlinear ordinary differential equations and an efficient Runge-Kutta-Fehlberg fourth-fifth order method along with shooting technique is employed to solve the reduced equations.
67 citations
TL;DR: In this paper, the three-dimensional mixed convection boundary layer flow of a nanofluid induced by an exponentially stretching sheet is numerically investigated in the presence of thermal radiation, heat source/sink and first-order chemical reaction effects.
Abstract: The three-dimensional mixed convection boundary layer flow of a nanofluid induced by an exponentially stretching sheet is numerically investigated in the presence of thermal radiation, heat source/sink and first-order chemical reaction effects. The adopted nanofluid model incorporates the effects of Brownian motion and thermophoresis into the mathematical model. The first-order velocity slip boundary conditions are also taken into account. The governing boundary layer equations are transformed into a set of nonlinear ordinary differential equations by employing suitable similarity variables. The resultant equations are solved numerically using the Runge-Kutta-Fehlberg method. Obtained solutions are compared with previous results in a limiting sense from the literature, demonstrating an excellent agreement. To show the typical trend of the solutions, a parametric study is conducted. The axial velocity, transverse velocity, temperature and nanoparticle volume fraction profiles as well as the skin-friction coefficient, Nusselt and Sherwood numbers are demonstrated graphically as a representative set of numerical results and discussed comprehensively.
65 citations
TL;DR: In this article, a new electrochemical sensor was developed and fabricated based upon the electrochemical polymerization of neutral red (NR) on the surface of carbon paste electrode (CPE), which shows electrocatalytic capability towards the simultaneous determination of catechol (CC) and hydroquinone (HQ) in presence of 0.2m phosphate buffer solution (PBS) at pH 7.4 with the scan rate of 50mV − 1.
63 citations
TL;DR: In this article, the authors considered the three-dimensional flow filling the porous space bounded by a bidirectional stretching sheet with nonlinear thermal radiation and heat source/sink.
Abstract: This article concerned with the three-dimensional flow fills the porous space bounded by a bidirectional stretching sheet with non-linear thermal radiation and heat source/sink. Maxwell fluid model is accounted as a working liquid. The imposed conditions for temperature and nanoparticle concentration are convective type. The self-similar forms of equations are obtained by the implementation of similarity variables. The solutions are computed via shooting algorithm with fourth-fifth-order Runge-Kutta-Fehlberg procedure. Comparison of obtained results with the known numerical solution is made and examined an excellent agreement. It is noted that the role of Brownian motion in temperature and heat transfer rate is significant. The results reveal that concentration of nanoparticles and temperature are decreased with an enhancement in Deborah number.
61 citations
TL;DR: In this paper, the authors explored the numerical study on squeezed flow of tangent hyperbolic fluid over a sensor surface with variable thermal conductivity and found that the variations of Weissenberg number, squeezed flow index parameter and permeable velocity parameter have strong influence on the momentum and thermal boundary layer thickness.
Abstract: The paper explores the numerical study on squeezed flow of tangent hyperbolic fluid over a sensor surface with variable thermal conductivity. The governing equations are reassembling into ordinary non-linear differential equations by using suitable transformation and ensuing differential equations are solved numerically by RKF45 technique. The results of impartment parameter on velocity and temperature profiles are given diagrammatically. It is found that the variations of Weissenberg number, squeezed flow index parameter and permeable velocity parameter have strong influence on the momentum and thermal boundary layer thickness.
TL;DR: The efficacy against multiple food-borne pathogens and therapeutic efficacy of T-C@AgNPs offers a valuable contribution in the area of nanotechnology and proved to be a first-class novel antimicrobial material for the first time in this study.
TL;DR: In this article, the three-dimensional flow of a Prandtl fluid over a Riga plate in the presence of chemical reaction and convective condition is investigated. And the converted set of boundary layer equations are solved numerically by RKF four-fifth method.
Abstract: The present study addresses the three-dimensional flow of a Prandtl fluid over a Riga plate in the presence of chemical reaction and convective condition. The converted set of boundary layer equations are solved numerically by RKF four-fifth method. Obtained numerical results for flow and mass transfer characteristics are discussed for various physical parameters. Additionally, the skin friction coefficient and Sherwood number are also presented. It is found that, the momentum boundary layer thickness is dominant for higher values of α and solutal boundary layer is low for higher Schmidt number and chemical reaction parameter.
TL;DR: In this paper, the authors deal with the study of heat and mass transfer on double-diffusive three-dimensional hydromagnetic boundary layer flow of an electrically conducting Casson nanofluid over a stretching surface.
Abstract: Purpose
This paper aims to deal with the study of heat and mass transfer on double-diffusive three-dimensional hydromagnetic boundary layer flow of an electrically conducting Casson nanofluid over a stretching surface. The combined effects of nonlinear thermal radiation, magnetic field, buoyancy forces, thermophoresis and Brownian motion are taken into consideration with convective boundary conditions.
Design/methodology/approach
Similarity transformations are used to reduce the governing partial differential equations into a set of nonlinear ordinary differential equations. The reduced equations were numerically solved using Runge–Kutta–Fehlberg fourth-fifth-order method along with shooting technique.
Findings
The impact of several existing physical parameters such as Casson parameter, mixed convection parameter, regular buoyancy ratio parameter, radiation parameter, Brownian motion parameter, thermophoresis parameter, temperature ratio parameter on velocity, temperature, solutal and nanofluid concentration profiles are analyzed through graphs and tables in detail. It is found that the solutal component increases for Dufour Lewis number, whereas it decreases for nanofluid Lewis number. Moreover, velocity profiles decrease for Casson parameter, while the Nusselt number increases for Biot number, radiation and temperature ratio parameter.
Originality/value
This paper is a new work related to three-dimensional double-diffusive flow of Casson nanofluid with buoyancy and nonlinear thermal radiation effect.
TL;DR: In this paper, a mathematical analysis of two-phase boundary layer flow and heat transfer of a Williamson fluid with fluid particle suspension over a stretching sheet has been carried out in the energy transfer process and the effect of influencing parameters on velocity and temperature transfer of fluid is examined and deliberated by plotted graphs and tabulated values.
Abstract: A mathematical analysis of two-phase boundary layer flow and heat transfer of a Williamson fluid with fluid particle suspension over a stretching sheet has been carried out in this paper. The region of temperature jump and nonlinear thermal radiation is considered in the energy transfer process. The principal equations of boundary layer flow and temperature transmission are reformed to a set of non-linear ordinary differential equations under suitable similarity transformations. The transfigured equalities are solved numerically with the help of RKF-45 order method. The effect of influencing parameters on velocity and temperature transfer of fluid is examined and deliberated by plotted graphs and tabulated values. Significances of the mass concentration of dust particle parameter play a key role in controlling flow and thermal behavior of non-Newtonian fluids. Further, the temperature and concern boundary layer girth are declines for increasing values of Williamson parameter.
TL;DR: In this article, the effect of non-linear convection in a laminar three-dimensional Oldroyd-B fluid flow is addressed, and the heat transfer phenomenon is explored by considering the nonlinear thermal radiation and heat generation/absorption.
Abstract: The effect of non-linear convection in a laminar three-dimensional Oldroyd-B fluid flow is addressed. The heat transfer phenomenon is explored by considering the non-linear thermal radiation and heat generation/absorption. The boundary layer assumptions are taken into account to govern the mathematical model of the flow analysis. Some suitable similarity variables are introduced to transform the partial differential equations into ordinary differential systems. The Runge-Kutta-Fehlberg fourth- and fifth-order techniques with the shooting method are used to obtain the solutions of the dimensionless velocities and temperature. The effects of various physical parameters on the fluid velocities and temperature are plotted and examined. A comparison with the exact and homotopy perturbation solutions is made for the viscous fluid case, and an excellent match is noted. The numerical values of the wall shear stresses and the heat transfer rate at the wall are tabulated and investigated. The enhancement in the values of the Deborah number shows a reverse behavior on the liquid velocities. The results show that the temperature and the thermal boundary layer are reduced when the non-linear convection parameter increases. The values of the Nusselt number are higher in the non-linear radiation situation than those in the linear radiation situation.
TL;DR: In this paper, nonlinear convective flow of magneto-Carreau-Casson liquids past a deformable surface under the aspects of heterogeneous and homogeneous reactions is investigated.
Abstract: Nonlinear convective flow of magneto-Carreau-Casson liquids past a deformable surface under the aspects of heterogeneous and homogeneous reactions is investigated. The present phenomenon also included the interaction of nonlinear radiation, Ohmic and Joule dissipations. At moderate to high temperature, the nonlinear convection and radiation are significant. The governed nonlinear system is illustrated numerically via Runge-Kutta based shooting scheme in the domain [ 0 , ∞ ) . Role of significant parameters on flow fields as well as on the fiction factor, heat and mass transportation rates are determined and discussed in depth. Comparison is done for distinct flow fields of Carreau and Casson fluids. It is evaluated that the velocities of Casson liquid are higher in comparison to Carreau fluid model. However, liquid temperature for Casson fluid model is weaker in comparison to Carreau fluid.
TL;DR: In this article, a two-phase model of conducting dusty fluid due to linearly stretching cylinder immersed in a porous media with the effect of radiation is considered, and the flow is described in terms of a "dusty gas" model, which treats the discrete phase (particles) and the continuous phase (fluid) as two continua occupying the same space.
Abstract: In the framework of the two-phase model, flow of a conducting dusty fluid due to linearly stretching cylinder immersed in a porous media with the effect of radiation is considered. The flow is described in terms of a ‘dusty gas’ model proposed by Saffman, which treats the discrete phase (particles) and the continuous phase (fluid) as two continua occupying the same space. Similarity transformations are used to convert the governing partial differential equations corresponding to momentum and energy equations into non-linear coupled ordinary differential equations. Numerical solutions of these equations are obtained using Runge–Kutta Fehlberg fourth-fifth order method and results are illustrated graphically. Comparisons with previously published work are performed and the results are found to be in good agreement. The numerical results for the local skin-friction coefficient and local Nusselt number are also presented.
TL;DR: In this article, a two phase dusty liquid model is considered and the role of physical parameters are focused in momentum and heat transport distributions, where stretching variables are utilized to transform the prevailing partial differential system into a nonlinear ordinary differential system, which is then solved numerically via Runge-Kutta-Fehlberg approach coupled with a shooting technique.
TL;DR: In this paper, the effect of Brownian motion and thermophoresis in nanofluid modeling is retained and a set of similarity variables are utilized to form an ordinary differential system from the prevailing partial differential equations.
TL;DR: In this article, the synthesis of 6-substituted-3-(1-(4-substantituted)-4-((Z)-(5,6-dimethoxy-1-oxo-1H-inden-2(3H)-ylidene)methyl) compounds was described.
TL;DR: In this paper, the exponential space dependent heat source (ESHS) process is utilized to explore the thermal transport characteristics of Marangoni convective flow in a Cu-H 2 O nanoliquid due to an infinite disk.
Abstract: The exponential space dependent heat source (ESHS) process is utilized to explore the thermal transport characteristics of Marangoni convective flow in a Cu-H 2 O nanoliquid due to an infinite disk. Flow is driven by linear temperature. Five distinct nanoparticle shapes such as sphere, tetrahedron, column, hexahedron and lamina are accounted. Impacts of Joule heating, radiation and viscous dissipation are also retained. Hamilton-Crosser’s expression is employed to deploy effective thermal conductivity of nanoliquid. Multi degree partial differential equations system is reduced by Karman transformations and then solved via shooting method. It is figured out that the heat transfer rate is enhanced for stronger Marangoni convection and nanoparticle volume fraction. Also, shape of the nanoparticles significantly affects the flow fields.
TL;DR: In this article, a carbon paste electrode was modified by nevirapine drug, the voltammetric behaviour of paracetamol and folic acid at modified carbon paste electrodes were investigated by cyclic voltammmetric technique.
TL;DR: In this paper, a co-precipitation method was used to produce a series of samarium substituted manganese ferrite nanoparticles, MnFe 2−x Sm x O 4 (x = 0.0, 0.5, 1.0) with oleic acid as surfactant.
TL;DR: In this paper, the impact of induced magnetic field over a flat porous plate by utilizing incompressible water-copper nanoliquid is examined analytically, where the plate is subjected to a regular free stream velocity as well as suction velocity.
Abstract: Impact of induced magnetic field over a flat porous plate by utilizing incompressible water-copper nanoliquid is examined analytically. Flow is supposed to be laminar, steady and two-dimensional. The plate is subjected to a regular free stream velocity as well as suction velocity. Flow formulation is developed by considering Maxwell–Garnetts (MG) and Brinkman models of nanoliquid. Impacts of thermal radiation, viscous dissipation, temperature dependent heat source/sink and first order chemical reaction are also retained. The subjected non-linear problems are non-dimensionalized and analytic solutions are presented via series expansion method. The graphs are plotted to analyze the influence of pertinent parameters on flow, magnetism, heat and mass transfer fields as well as friction factor, current density, Nusselt and Sherwood numbers. It is found that friction factor at the plate is more for larger magnetic Prandtl number. Also the rate of heat transfer decayed with increasing nanoparticles volume fraction and the strength of magnetism.
TL;DR: In this article, the authors compacts with effect of nonlinear convection and radiation on tangent hyperbolic fluid flow of through a convectively heated vertical surface and solve the converted set of boundary layer equations numerically by Runge-Kutta-Fehlberg method.
Abstract: The current study compacts with effect of nonlinear convection and radiation on tangent hyperbolic fluid flow of through a convectively heated vertical surface. The converted set of boundary layer equations are solved numerically by Runge-Kutta-Fehlberg method. The effect of various pertinent parameters on flow and heat transfer characteristics are discussed with tabulated numerical values and deliberate figures. Additionally, the skin friction coefficient and Nusselt number are also presented. We noticed that, the skin friction factor and heat transfer rates are higher in presence of nonlinear convection than its absence. Further, velocity profile decreases by increasing power law index but establishes opposite results for skin friction.
TL;DR: It is concluded that BP-1T acts on HIF-1α degradation through p53/MDM2 proteasome pathway, eventually leading to abolition of migration and invasion in solid tumour.
Abstract: Hypoxia is a feature of all solid tumours, contributing to tumour progression. Activation of HIF-1α plays a critical role in promoting tumour angiogenesis and metastasis. Since its expression is positively correlated with poor prognosis for cancer patients, HIF-1α is one of the most convincing anticancer targets. BP-1T is a novel antiproliferative agent with promising antiangiogenic effects. In the present study, the molecular mechanism underlying cytotoxic/antiangiogenic effects of BP-1T on tumour/non-tumour angiogenesis was evaluated. Evidences show that BP-1T exhibits potent cytotoxicity with prolonged activity and effectively regressed neovessel formation both in reliable non-tumour and tumour angiogenic models. The expression of CoCl2-induced HIF-1α was inhibited by BP-1T in various p53 (WT)-expressing cancer cells, including A549, MCF-7 and DLA, but not in mutant p53-expressing SCC-9 cells. Mechanistically, BP-1T mediates the HIF-1α proteasomal degradation by activating p53/MDM2 pathway and thereby downregulated HIF-1α-dependent angiogenic genes such as VEGF-A, Flt-1, MMP-2 and MMP-9 under hypoxic condition of in vitro and in vivo solid tumour, eventually leading to abolition of migration and invasion. Based on these observations, we conclude that BP-1T acts on HIF-1α degradation through p53/MDM2 proteasome pathway.
TL;DR: In this article, the performance of a modified carbon paste electrode (CPE) with alanine and tyrosine functionalized nanoflakes (TGONF) was investigated.
TL;DR: In this paper, the effect of TX-100 on the reactivity of FC molecules at the FMCPE interface was studied using the analytical Fukui and cyclic voltammetry (CV) to understand the electron transfer (ET) nature of ferrocene.
TL;DR: In this paper, the temperature-dependent heat source/sink in Maxwell nanoliquid flow towards a riga plate is investigated, and similarity transformations are applied to convert the governing dimensional expressions into non-dimensional forms.
Abstract: The temperature-dependent heat source/sink in Maxwell nanoliquid flow towards a riga plate is investigated. In this model, we incorporated convective heat and mass boundary conditions. Similarity transformations are applied to convert the governing dimensional expressions into non-dimensional forms. Finite difference method along with Richardson extrapolation technique is utilized to elaborate the numerical solutions of physical phenomenon. Effects of different values of governing parameters on velocity, temperature and concentration profiles are evaluated via graphs. The quantities of interest like Nusselt and Sherwood numbers are discussed in detail through numerical data.