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Effects of suction-injection-combination (SIC) on the onset of Rayleigh-Benard magnetoconvection in a micropolar fluid
The effects of suction-injection-combination (SIC) and magnetic field on the linear stability analysis of Rayleigh-Benard convection in a horizontal layer of an Boussinesq micropolar fluid is studied using a Rayleigh-Ritz techinque. The eigenvalues are obtained for free-free, rigid-free and rigid-rigid velocity boundary combinations with isothermal and adiabatic temperature conditions on the spin-vanishing boundaries. The eigenvalues are also obtained for lower rigid isothermal and upper free adiabatic boundaries with vanishing spin. The influence of various micropolar fluid parameters on the onset of convection has been analysed. It is found that the effect of Prandtl number on the stability of the system is dependent on the SIC being pro-gravity or anti-gravity. A similar Pe-sensitivity is found in respect of the critical wave number. It is observed that the micropolar fluid layer heated from below is more stable compared to the classical fluid layer. 2003 Elsevier Science Ltd. All rights reserved. -
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EFFECTS OF SINUSOIDAL AND NON-SINUSOIDAL TEMPERATURE MODULATION IN A TRIPLE DIFFUSIVE CONVECTION
The Triple Diffusive convection with time-dependent sinusoidal (cosine) and non-sinusoidal (square and triangular) temperature modulation is studied using linear and non-linear analysis. The expression for Rayleigh number and correction Rayleigh number is obtained by using perturbation method which gives the prospect to control the convection. Effects of various parameters of the problem are individually studied for two cases of temperature modulation namely, (i) in-phase and (ii)out-of-phase. Ginzburg-Landau equation using multi-scale method is derived to study the effects of temperature modulation on heat and mass transfer. It is observed that both solutal Rayleigh numbers stabilizes or destabilizes the system depending on the values of the frequency of modulation. 2021 I??k University, Department of Mathematics. All Rights Reserved. -
Effects of Rough Boundaries on RayleighBenard Convection in Nanofluids
A linear stability analysis of RayleighBenard convection in a Newtonian nanofluid is carried out using most general boundary conditions. A single-phase description of nanofluids is adopted in the study. The nanofluids used for the study are wateralumina and watercopper nanofluids in order to analyze how a choice between them can be made. The values of thermophysical quantities of nanofluids are calculated using the mixture theory and phenomenological-laws. The paper applies the Maclaurin series in solving the boundary-eigenvalue-problem through a simple and innovative approach. A single-term Galerkin technique is adopted to obtain the guess value of the critical Rayleigh number and the wave number. Further, improved values of the Rayleigh number and the wave number are obtained using the solution of a system of three linear-algebraic equations. A detailed discussion is made on the effect of rough-boundaries and Robin-boundary conditions for temperature on the onset of convection. A comparative study between the results of two nanofluids is made and the destabilizing effect of nanoparticles in the Newtonian carrier-fluid on the onset of convection is studied. Copyright 2023 by ASME. -
Effects of reduced graphene oxide on nonlinear absorption and optical limiting properties of spin coated aluminium doped zinc oxide thin films
In this work, we investigate the nonlinear absorption and optical limiting properties of reduced graphene oxide (rGO) incorporated aluminum doped zinc oxide (AZO) composite thin films by open aperture z-scan technique using Q-switched Nd:YAG laser at 532 nm. The structural and spectral properties were also systemically analyzed. The composite thin films were synthesized by spin coating technique with online infrared curing facility. Studies on nonlinear optical responses of the investigated samples proved a substantial enhancement in the nonlinear absorption coefficient of AZO:rGO composites compared to AZO thin film. The nonlinear absorption is attributed to the two photon absorption with reverse saturable absorption. The strong nonlinear absorption and nonlinear scattering effects result in the optical limiting property of the composite material. The AZO:rGO thin film exhibits lower optical limiting threshold value (32 MW/cm2) as compared to AZO (59 MW/cm2). Hence it is an excellent optical limiter which explores applications in the field of optoelectronics as protecting material for sensitive photonic devices. 2021 -
Effects of Processing Parameters on Microstructure Evolution of Al-7Si-Mg Alloy by Cooling Slope Casting
This work investigates the effects of pouring temperature, slope length, and slope temperature in cooling slope casting on the formation of globular microstructure of Al-7Si-Mg alloy. The remnant alloy on the slope during casting was quenched and characterized at different stages of flow to evaluate the microstructure features developed in cooling slope casting. The primary ?-Al dendritic phase found in conventional cast alloy was transformed into globular shape in slope-processed cast alloy. Finer and more homogenous primary ?-Al phase was formed at lower pouring temperature (625C). The effect of slope length on microstructure of Al-7Si-Mg alloy was significant at high pouring temperatures (640 and 660C) but was not visible at low pouring temperature (625C). The microstructure of alloy became coarser with increasing slope temperature. 2015, ASM International. -
Effects of Performance and Target Pressure on the Psychological Well-Being of Corporate Employees
The main objective of this study is to analyze the work stress on the performance of the employees effectively and to analyze the effect of work stress on the well-being of the employees. The influence of psychological well-being and the capability to tackle workload in the company environment. The main objectives are better job performance which helps in achieving higher productivity. Individual objectives and the organizational objectives of the company assists in the overall performance and gross achievement of the organization. The significant well-being of the overall performance of the employee, their influence, and the management of stress of the performance of the employees. This analysis showcases the impact of work stress on the growth of the employees, which effects performance and significant growth to employee development. 2023, Journal for ReAttach Therapy and Developmental Diversities. All Rights Reserved. -
Effects of Peer Monitoring on Student Stress Level of College Students Based on Multi-Layer Perceptron Approach
The classroom is just one of many places where the proposed approach encounter stress. Previous studies have shown that college students experience high rates of stress. It is not known if the Student Stress Inventory-Stress Manifestations (SSI-SM) is useful in identifying stressors and evaluating stress manifestations among college students. To this end, it was created a college-specific version of the Student Stress Inventory-Stress Manifestations (SSI-SM) and administered it to students to determine its validity and reliability. These procedures comprise the proposed technique and include preprocessing, feature selection, and model training. It uses Normalization as a preprocessing approach. The term' normalization' refers to the procedure of rescaling or modifying data so that all categories have the same variance. The proposed approach employed linear discriminant analysis as a means of selecting features. The models are then trained using MLP after information gain has been used to choose relevant features. The proposed approach achieves better results than the two leading alternatives, CNN and RNN. 2024 IEEE. -
Effects of non-uniform temperature gradient and magnetic field on the onset of convection in fluids with suspended particles under microgravity conditions
The effects of a non-uniform temperature gradient and magnetic field on the onset of convection driven by surface tension in a horizontal layer of Boussinesq fluid with suspended particles confined between an upper free / adiabatic boundary and a lower rigid / isothermal boundary have been considered. A linear stability analysis is performed. The microrotation is assumed to vanish at the boundaries. The Galerkin technique is used to obtain the eigenvalues. The influence of various parameters on the onset of convection has been analysed. Six different non-uniform temperature profiles are considered and their comparative influence on onset is discussed. It is observed that the electrically conducting fluid layer with suspended particles heated from below is more stable compared to the classical electrically conducting fluid without suspended particles. The critical wave number is found to be insensitive to the changes in the parameters but sensitive to the changes in the Chandrasekhar number. The problem has possible applications in microgravity space situations. -
Effects of nitrogen, sulphur, and temperature treatments on the spectral, structural, and electrochemical characteristics of graphene oxide for energy storage applications
The structural and surface modifications have been studied on the hydrothermally Nitrogen (N) and Sulphur (S) doped and thermally reduced at 350 C nitrogen-doped, nitrogen-sulfur-doped graphene oxides. Raman spectra confirmed the reduction of graphene oxides by shifts in position and intensity variations of the D and G bands. EDX and mapping images revealed the carbon-oxygen ratio as well as the doping of nitrogen and sulphur into two-dimensional graphene oxide. The electrochemical properties of undoped and doped graphene oxides were investigated using a three-electrode system using a 1 M KOH electrolyte. It shows how doping, and reduction improve current conduction in graphene oxides. The specific capacitance of N,S-rGO after being synthesized and reduced at 350C was 930 Fg?1 and 1059 Fg?1, respectively, according to cyclic voltammetry results. The N-rGO specific capacitance was found to be similar, with 850 Fg?1 and 891 Fg?1, respectively, for the as prepared and reduced at 350C. The charge-discharge analysis, cycle stability, and impedances for the applied frequency ranges of undoped and doped graphene oxides for energy storage applications have all been estimated and discussed. 2023 -
Effects of Macro Economic Indicators on Foreign Portfolio Investments
In this study, both institutional and retail investors were observed making exits and entries based on macroeconomic data, utilizing measurable indicators such as GDP, inflation, bank rates, foreign exchange rates, trade volume on the national stock exchange, and portfolio investments. Employing a Vector Error Correction Model (VECM) in an econometric analysis, the study found a significant association between macroeconomic indicators and portfolio investments in India. Investors followed a discernible pattern of entering and exiting markets, with economic growth fostering greater investments. Notably, GDP, NSE Volume, and bank rates were identified as variables impacting foreign portfolio investments. In the long run, GDP positively affected foreign portfolio investments, while inflation and foreign exchange rates exhibited a detrimental influence, leading to decreased portfolio investments. Foreign Institutional Investors, prioritizing profits over business operations, focused on market sentiments, directing investments towards economies with potential performance and resulting in a higher volume of capital inflow. Overall, the study concludes that a robust economic condition attracts superior foreign portfolio investments. 2024 IEEE. -
Effects of hall current on transient flow of dusty fluid with nonlinear radiation past a convectively heated stretching plate
Influence of Hall current on flow and heat transfer of dusty fluid over a convectively heated stretching plate in the presence of nonlinear thermal radiation is explored in this paper. The unsteadiness in the flow and temperature fields is because of the time-dependent stretching velocity and surface temperature. Suitable similarity transformations are used to convert the governing partial differential equations of momentum and thermal energy to a system of nonlinear ordinary differential equations. Consequent equations are solved by using shooting method. The details of the velocities, temperatures, local Nusselt number as well as local skin friction for various parameters such as unsteadiness parameter, thermal radiation, Hall effects, Biot number, Eckert number, Prandtl number and magnetic parameter are presented graphically and discussed in detail. 2018 Trans Tech Publications, Switzerland. -
Effects of green energy and productivity on environmental sustainability in BRICS economies: The role of natural resources rents
By developing a theoretical framework, this paper constructs two models for environmental sustainability, each with an ecological footprint and CO2 emissions. The empirical study considers panel data from Brazil, Russia, India, China, and South Africa (BRICS) based on the need for consistent economic growth with minimum environmental cost in these five major emerging countries. The data period ranges from 1994 to 2018. According to the findings from several estimation techniques, total factor productivity and renewable energy consumption improve environmental quality. However, natural resources rents and economic growth are detrimental to environmental sustainability. Therefore, it is concluded that the mere blind use of natural resources to achieve economic growth without raising productivity and green energy is ecologically unsustainable. Appropriate policies are discussed to promote the productivity of governments via emerging technologies and digitalisation. 2024 Elsevier Ltd -
Effects of global warming, time delay and chaos control on the dynamics of a chaotic atmospheric propagation model within the frame of Caputo fractional operator
The Lorenz-84 climate model is a simplified mathematical model that describes the chaotic behavior of atmospheric convection and its impact on global climate patterns. It captures the presence of chaotic behavior in the motion of westerly wind and helps understand the concept of sensitivity to initial conditions. But as observed over the years, the westerlies are gaining more strength due to the rise in atmospheric temperature. In this work, we have modified the old model to observe the changes in the behavior of the system due to global warming and time delay. The modified model has been generalized using Caputo fractional derivative to provide a more accurate representation of the system with memory effect and non-local behavior. The stability of the new model has been tested at all the equilibrium points. Using Picard's operator and Banach's Fixed Point theorem, it has been shown that there exists a unique and bounded solution for the new model. It has been observed that the sole effect of global warming makes the system gradually unstable from chaotic as the fractional order ? is decreased from 0.80 to 0.50. Also, a shift in the bifurcation point has been noticed for the new model. All three Lyapunov exponents have been calculated for different fractional orders to confirm the presence of chaos in the modified model as well. A chaos control law has been constructed for the modified chaotic model using the sliding mode control theory. Interestingly, the chaos disappears completely when the effect of time-delay is considered in the modified model. Since our proposed time-delayed modified model shows an asymptotically stable nature for all fractional orders ? less than 0.85, it is better suited to make more accurate predictions about the strength of the westerlies. 2023 Elsevier B.V. -
Effects of Financial and Trade Globalization on Total Factor Productivity Growth in Emerging Economies
This article considers the annual sample from 1984 to 2019 in a panel dataset of 20 emerging economies (i.e. Brazil, Chile, China, Colombia, the Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Kuwait, Malaysia, Mexico, Peru, the Philippines, Poland, Saudi Arabia, South Africa, Thailand, and Turkey) given by Morgan Stanley Capital International (MSCI), to explore the effects of trade and financial globalization on total factor productivity (TFP) growth. It considers domestic credit to the private sector by banks as a percentage of gross domestic product (GDP), labor force, and total gross fixed capital formation as a percentage of GDP as control variables in the total factor productivity function. The article considers the direct effects of trade and financial globalization. It also checks the moderating impact of domestic credit on TFP. The long-run estimation shows that domestic credit, labor force, and financial globalization reduce TFP growth, whereas investments and trade globalization enhance it. Interestingly, their moderating effect enhances TFP in the long run. The policy implications are also discussed. 2023 Taylor & Francis Group, LLC. -
Effects of Euphorbia thymifolia and Euphorbia hirta leaf extracts on membrane-bound, mitochondrial enzymes and lipid profile of carbon tetrachloride-induced hepatotoxicity in rats
The present investigation was aimed to identify the potentiality of Euphorbia thymifolia Linn. and Euphorbia hirta Linn. leaf extract on the toxin-induced (carbon tetrachloride- CCl4) Albino Wistar rats. The animals were grouped into 7 categories including control (basal diet, G1), CCl4-induced (1.5 mL/kg, b.w., i.p.) (G2), G1 administrated with 300 mg/kg b.w., extract of E. thymifolia (G3) and E. hirta (G4), G2 administrated with 300 mg/kg b.w., extract of E. thymifolia (G5), E. hirta (G6), and standard drug (silymarin 25 mg/kg b.w.; G7) for 21- days trial period with each group contains 6 rats. The samples were collected and the following parameters including mitochondrial enzymes, different ATPase and lipid profiles were analyzed. The membrane-bound enzymes, the mitochondrial enzymes levels and the lipid profiles were reduced in the toxin-induced rats but the levels of enzymes were restored, significantly increased and lipid profiles are returned to the normal in the treatment of both extracts. 2022 Visagaa Publishing House. -
Effects of dark matter on the upper bound mass of neutron stars
Observations have indicated that we do not see neutron stars (NS) of mass near the theoretical upper limit as predicted. Here we invoke the role of dark matter (DM) particles in star formation, and their role in lowering the mass of remnants eventually formed from these stars. Massive stars can capture DM particles more effectively than the lower mass stars, thus further softening the equation of state of the remnant neutron stars. We also look at the capture of DM particles by the NS, which could further soften the upper mass limit of NS. The admixture of DM particles would be higher at earlier epochs (high z). 2020 Elsevier B.V. -
Effects of dark matter in star formation
The standard model for the formation of structure assumes that there existed small fluctuations in the early universe that grew due to gravitational instability. The origins of these fluctuations are as yet unclear. In this work we propose the role of dark matter in providing the seed for star formation in the early universe. Very recent observations also support the role of dark matter in the formation of these first stars. With this we set observable constraints on luminosities, temperatures, and lifetimes of these early stars with an admixture of dark matter. 2019, Springer Nature B.V. -
Effects of dark matter in red giants
Dark matter (DM) which constitutes five-sixths of all matter is hypothesized to be a weakly interacting non-baryonic particle, created in the early stages of cosmic evolution. It can affect various cosmic structures in the Universe via gravitational interactions. The effect of DM in main sequence stars and stellar remnants like neutron stars and white dwarfs has already been studied. Red giant phase is a late stage of the evolution of stars. In this work, we study, low-mass red giants stars with admixture of DM and how this can effectively change the intrinsic properties of red giants such as their luminosities, temperatures and lifetimes. 2020 Elsevier B.V. -
Effects of chemical reaction and partial slip on the three-dimensional flow of a nanofluid impinging on an exponentially stretching surface /
The European Physical Journal Plus, Vol.132, Issue 113, pp.1-18, ISSN: 2190-5444.