Browse Items · CHRIST (Deemed To Be University) Institutional Repository

Nonlinear analysis of the effect of viscoelasticity on ferroconvection

Thispaper concerns a nonlinear analysis of the effects of viscoelasticity on convection in ferroliquids. We consider the Oldroyd model for the constitutive equation of the liquid. The linear stability analysis yields the critical value of the Rayleigh number for the onset of oscillatory convection in Maxwell and Jeffrey ferroliquids. The use of a minimal mode double Fourier series in the nonlinear perturbation equations yields a KhayatLorenz model for the ferromagnetic liquid, and that is scaled further to get the classical Lorenz model as a limiting case. The scaled KhayatLorenz model thus obtained is solved numerically and the solution is used to compute the time-dependent Nusselt number, which quantifies the heat transport. The results are analyzed for the dependence of the time-averaged Nusselt number on different parameters. 2021 Wiley Periodicals LLC

Article

Nonlinear 3D flow of Casson-Carreau fluids with homogeneousheterogeneous reactions: A comparative study

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. 2017

Book Chapter

NONHUMAN VISIONS: From Experimental Cinema to Hollywood

In this chapter, I want to trace the convergences between experimental cinema, video-art practices and Hollywood that has emerged as a result of their mutual investment in capturing the visuality of the Anthropocene through a technologically produced and mediated sensory framework. Through a series of case studies from independent filmmakers and Hollywood blockbusters, I argue that as much as the avant-garde is invested in producing Anthropocenic imaginations, Hollywood has also been pursuing it by creating a series of affective strategies that help us to conceive and relate to an otherwise incomprehensible scales of deep-pasts and futures. 2024 selection and editorial matter, Simi Malhotra, Sakshi Dogra and Jubi C. John; individual chapters, the contributors.

Article

Nondestructive and cost-effective silkworm, Bombyx mori (Lepidoptera: Bombycidae) cocoon sex classification using machine learning

Sericulture is the process of cultivating silkworm cocoons for the production of silks. The quality silk production requires quality seed production which in turn requires accurate classification of male and female pupa in grainage centers. The challenges in the current methods of silkworm cocoon sex classification using manual observation lie in the time-consuming nature of the process, potential human error, and difficulties in accurately discerning subtle morphological differences between male and female cocoons. FC1 and FC2 single hybrid variety breed pupa are commonly used in south India for the production of high yielding double hybrid bivoltine silkworm seeds. In this study, 1579 FC1 and 1669 FC2 variety samples were used for the classification process. To overcome the challenges of present physical observation by expert employees, camera images of FC1 and FC2 cocoons were used in this study for sex classification. The proposed model used Histogram Oriented Gradient (HOG) feature descriptor of cocoon samples. Linear Discriminant Analysis (LDA) was applied on the feature vector to reduce the dimension and this feature matrix was given to the classical machine learning algorithms support vector machine (SVM), k-nearest neighbors (kNN), and gaussian nae bayes for classification with stratified 10-fold cross validation. The results showed that for FC1 data HOG + LDA + Nae Bayes performed better with a mean accuracy of 95.3% and for FC2 data HOG + LDA + KNN attained a mean accuracy of 96.2%. Our results suggest that this camera imaging method can be used efficiently in the classification based on the cocoon size and shape of different breeds. African Association of Insect Scientists 2024.

Article

Non-Recombinant Mutagenesis of Bacillus mojavensis CUIE1819 for Hyper Production of Lipase and Treatment of Polluted Lakes

Microorganisms that degrade oil contribute significantly to the bioremediation of polluted lakes. Many microorganisms synthesize lipases, which are commercially significant. In the present study microorganisms producing extracellular lipase were isolated from various polluted lakes in Bangalore by using tributyrin agar. A lipase assay was done to determine the most efficient lipase-producing organism, which was then named Bacillus mojavensis CUIE1819 based on 16srRNA sequencing. After UV irradiation, the selected immobilized organisms were used to treat the lake water samples. 2022, Association of Biotechnology and Pharmacy. All rights reserved.

Article

Non-Noble Bifunctional Amorphous Metal Boride Electrocatalysts for Selective Seawater Electrolysis

The global scarcity of freshwater resources has recently driven the need to explore abundant seawater as an alternative feedstock for hydrogen production by water-splitting. This route comes with new challenges for the electrocatalyst, which has to withstand harsh saline water conditions with selectivity towards oxygen evolution over other competing reactions. Herein, a series of amorphous metal borides based on the iron triad metals (Co, Ni, and Fe), synthesized by a simple one-step chemical reduction method, displayed excellent bifunctional activity for overall seawater splitting. Amongst the chosen catalysts, amorphous cobalt boride (Co?B) showed the best overpotential values of 182 mV for HER and 305 mV for OER, to achieve 10 mA/cm2, in alkaline simulated seawater. This superior activity was owed to the enrichment of the metal site with excess electrons (HER) and the in-situ surface transformation (OER), as confirmed by various means. In alkaline simulated seawater, the overall cell voltage required to achieve 100 mA/cm2 was 1.85 V for the Co?B catalyst when used in a 2-electrode assembly. The Co?B catalyst showed negligible loss in activity even after 1000 cycles and 50 h potentiostatic tests, thus demonstrating its industrial viability. The selectivity of the catalyst was established with Faradaic efficiency of above 99 % for HER and 96 % for OER, with no detection of chloride products in the spent electrolyte. This study using the mono-metallic boride catalysts will turn to be a precursor to exploit other complex metal boride systems as potential candidates for seawater electrolysis for large-scale hydrogen production. 2023 Wiley-VCH GmbH.

Article

Non-linear Dynamics of CuO?MgO?TiO2 ?H2O Ternary Nanofluid Flowing Past a Rotating Cone in the Presence of Thermal Radiation

The flow of ternary nanofluid past a rotating cone has been analysed using the Ternary nanofluid model. The ternary nanofluid is formed by suspending CuO, MgO and TiO2 nanoparticles into water. The nanoparticles that are suspended in the base fluid are assumed to be in the shape of a sphere so that there will be minimum friction between the nanoparticles and the surface as a result this will allow the fluid to flow with less frictional force. Such a characteristic flow finds application in automobiles, production industries, metallurgical process, solar appliances etc. Hence, in order to analyse the heat transfer characteristics of ternary nanofluid, a mathematical model is framed with the help of partial differential equations considering thermal radiation and heat source/sink to achieve realistic results. These equations are further transformed to non-linear differential equations that are solved using RKF-45 technique. The results of this study are interpreted graphically for various parameters corresponding to the fluid flow. The outcomes of this study indicated that the increase in convection enhanced the tangential velocity of the flow and the nanofluid temperature. Whereas, the increase in the thermal slip reduced the tangential flow velocity as well as the temperature of the nanofluid. 2023 L&H Scientific Publishing, LLC. All rights reserved

Conference Paper

Non-linear Convection in Couple Stress Fluid with Non-classical Heat Conduction Under Magnetic Field Modulation

A theoretical examination of thermal convection for a couple stress fluid which is electrically conducting and possessing significant thermal relaxation time is explored under time dependent magnetic field. Fouriers law fails for a diverse area of applications such as fluids subjected to rapid heating, strongly confined fluid and nano-devices and hence a non-classical heat conduction law is employed. The heat transport in the system is examined and quantified employing the Lorenz model. The Nusselt number is deduced to quantitate the transfer of heat. 2021, Springer Nature Singapore Pte Ltd.

Article

Non-linear convection in chemically reacting fluid with an induced magnetic field across a vertical porous plate in the presence of heat source/sink

An investigation is carried out to observe the impacts of non-linear convection and induced magnetic field in the flow of viscous fluid over a porous plate under the influence of chemical reaction and heat source/sink. The plate is subjected to a regular free stream velocity as well as a suction velocity. The subjected non-linear problem is non-dimensionalized and analytic solutions are presented via perturbation method. The graphs are plotted to analyze the effect of relevant parameters on velocity, induced magnetic field, heat and mass transfer fields as well as friction factor, current density, Nusselt and Sherwood numbers. It is established that nonlinear convection aspect is destructive for thermal field and its layer thickness. The magnetic field effect enhances the thermal field while it reduces the velocity field. Also, the nonlinear effect subsides heat transfer rate significantly. 2018 Trans Tech Publications, Switzerland.

Article

Non-inverse signed graph of a group

Let G be a group with binary operation *. The non-inverse graph (in short, i*-graph) of G, denoted by ?, is a simple graph with vertex set consisting of elements of G and two vertices x, y ? ? are adjacent if x and y are not inverses of each other. That is, x ? y if and only if x * y ?= iG ?= y*x, where iG is the identity element of G. In this paper, we extend the study of i*-graphs to signed graphs by defining i*-signed graphs. We characterize the graphs for which the i*-signed graphs and negated i*-signed graphs are balanced, sign-compatible, consistent and k-clusterable. We also obtain the frustration index of the i*-signed graph. Further, we characterize the homogeneous non-inverse signed graphs and study the properties like net-regularity and switching equivalence. Amreen J., Naduvath S., 2024.