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Heat transfer optimization and sensitivity analysis of Marangoni convection in nanoliquid with nanoparticle interfacial layer and cross-diffusion effects
Heat and mass transfer induced by Marangoni forces occur frequently in crystal growth and heat pipes, especially in microgravity situations. Therefore, the heat and mass transfer optimization in the thermosolutal Marangoni boundary layer flow of a nanomaterial with cross-diffusion effects is carried out in this study. Thermal radiation, magnetic field, and cross-diffusion are also incorporated in the thermal phenomena. The flow fields with nanolayer and without it are compared. The nanoparticle interfacial layer aspect accounted for in the nanofluid model makes the modeling more realistic. The optimization procedure is based on the Response Surface Methodology (RSM) model that utilizes the face-centered Central Composite Design (fc-CCD). The external constraining factors of the system like thermal radiation, magnetic field, and nanoparticle loading are explored for interactive impacts. The sensitivity of the heat and mass transfer is scrutinized. The interfacial layer aspect leads to an enhanced magnitude of the temperature field whereas the effect on the concentration profile is negligible. The inclination of the magnetic field augments the flow profiles significantly. The highest sensitivity of the heat and mass transfer is towards the thermal radiation aspect. The optimized output of heat and transfer rate is estimated to be when R = 1.6639, M = 1, and ? = 1 %. 2021 Elsevier Ltd -
A POWERFUL ITERATIVE APPROACH for QUINTIC COMPLEX GINZBURG-LANDAU EQUATION within the FRAME of FRACTIONAL OPERATOR
The study of nonlinear phenomena associated with physical phenomena is a hot topic in the present era. The fundamental aim of this paper is to find the iterative solution for generalized quintic complex Ginzburg-Landau (GCGL) equation using fractional natural decomposition method (FNDM) within the frame of fractional calculus. We consider the projected equations by incorporating the Caputo fractional operator and investigate two examples for different initial values to present the efficiency and applicability of the FNDM. We presented the nature of the obtained results defined in three distinct cases and illustrated with the help of surfaces and contour plots for the particular value with respect to fractional order. Moreover, to present the accuracy and capture the nature of the obtained results, we present plots with different fractional order, and these plots show the essence of incorporating the fractional concept into the system exemplifying nonlinear complex phenomena. The present investigation confirms the efficiency and applicability of the considered method and fractional operators while analyzing phenomena in science and technology. 2021 The Author(s). -
Stirling number of the fourth kind and Lucky partitions of a finite set
The concept of Lucky k-polynomials and in particular Lucky ?polynomials was recently introduced. This paper introduces Stirling number of the fourth kind and Lucky partitions of a finite set in order to determine either the Lucky k- or Lucky ?-polynomial of a graph. The integer partitions influence Stirling partitions of the second kind. 2021 Azarbaijan Shahid Madani University. -
Nontoxic photoluminescent tin oxide nanoparticles for cell imaging: Deep eutectic solvent mediated synthesis, tuning and mechanism
Non-toxic and photoluminescent (PL) tin oxide nanoparticle synthesis in Deep Eutectic Solvents (DESs) is being reported herein. Both radiation (electron beam and ? radiation) and solvothermal methods were employed for the synthesis. An electron beam radiation technique proved to be more appropriate in tuning the size and morphology compared to the solvothermal process. Addition of any external oxido-reductive or stabilizing agent could be avoided by the use of Reline (choline chloride?:?urea; 1?:?2) as the host matrix. Detailed analysis of the PL behaviour of the nanoparticles is another important aspect of this study. The oxygen vacancies and tin interstitials responsible for photoluminescence have been identified from the de-convoluted PL spectra of the nanoparticles. Time dependent PL kinetics depicts PL decay at ?1.2 ns due to near band edge emission and at ?3.15 ns due to defect state emission. The synthetic process has been standardized focusing on the size of the particles by varying all possible experimental parameters such as the temperature, concentration of the precursors, reaction time, dose of irradiation and dose rate. Synthesized nanoparticles have been characterized using XRD, XPS and EDX. TEM images illustrate nanomorphological differences obtained in the two methods. The probable mechanism of synthesis (both radiation and thermal) has been proposed based on the results obtained from transient studies using electron pulses and FTIR experiments. Cytotoxicity data demonstrate that the nanoparticles are suitable for application in biological studies involving cells up to a concentration of 10 ?M. Imaging experiments with these photoluminescent nanoparticles exhibit their ubiquitous distribution including the nucleus of the tumour cells, which signifies potential application of these NPs for targeted drug delivery in cancer chemotherapy. Furthermore, the nanoparticles exhibited excellent antioxidant properties in vitro. The findings herein can open up enormous possibilities for more advanced and dedicated research towards using this cheap and versatile nanomaterial in a variety of biomedical applications. 2021 The Royal Society of Chemistry. -
A new combinational technique in image steganography
Internet is used for exchanging information. Sometimes it is needed to transmit confidential data via internet. Here the authors use image steganography to pass confidential data within a cover image. To construct the algorithm, they take the combinational help of particle swarm optimization (PSO), bi-orthogonal wavelet transform (BWT), and genetic algorithm (GA). They use PSO to take the enhanced version of cover image. They use BWT to choose the selective sub bands of cover image and we utilize GA to select a particular stego image among a set of stego images. Thus, an innovative technique of image steganography has been made to transmit confidential data via cover image generating stego image. This combinational approach of image steganography is quite safe for confidential data transmission and makes it hard for the attackers to retrieve the confidential data. 2021 IGI Global. All rights reserved. -
3-Sequent achromatic sum of graphs
Three vertices x,y,z in a graph G are said to be 3-sequent if xy and yz are adjacent edges in G. A 3-sequent coloring (3s coloring) is a function ?: V (G) ?{1, 2,...,k} such that if x,y and z are 3-sequent vertices, then either ?(x) = ?(y) or ?(y) = ?(z) (or both). The 3-sequent achromatic number of a graph G, denoted ?3s(G), equals the maximum number of colors that can be used in a coloring of the vertices' of G such that if xy and yz are any two sequent edges in G, then either x or z is colored the same as y. The 3-sequent achromatic sum of a graph G, denoted a'3s(G), is the greatest sum of colors among all proper 3s-coloring that requires ?3s(G) colors. This research initiates the study of 3-sequent achromatic sum and finds the exact values of this parameter for some known graphs. Furthermore, we calculate the a'3s(G) of corona product, Cartesian product of the graphs and some important results have been proved and a comparative study is carried out. 2021 World Scientific Publishing Company. -
Numerical simulation for coupled nonlinear Schringer-Korteweg-de Vries and Maccari systems of equations
The primary goal of this paper is to seek solutions to the coupled nonlinear partial differential equations (CNPDEs) by the use of q-homotopy analysis transform method (q-HATM). The CNPDEs considered are the coupled nonlinear Schringer-Korteweg-de Vries (CNLS-KdV) and the coupled nonlinear Maccari (CNLM) systems. As a basis for explaining the interactive wave propagation of electromagnetic waves in plasma physics, Langmuir waves and dust-acoustic waves, the CNLS-KdV model has emerged as a model for defining various types of wave phenomena in mathematical physics, and so forth. The CNLM model is a nonlinear system that explains the dynamics of isolated waves, restricted in a small part of space, in several fields like nonlinear optics, hydrodynamic and plasma physics. We construct the solutions (bright soliton) of these models through q-HATM and present the numerical simulation in form of plots and tables. The solutions obtained by the suggested approach are provided in a refined converging series. The outcomes confirm that the proposed solutions procedure is highly methodological, accurate and easy to study CNPDEs. 2021 World Scientific Publishing Company. -
Size Tuning, Phase Stabilization, and Anticancer Efficacy of Amorphous Selenium Nanoparticles: Effect of Ion-Pair Interaction, ?OH Functionalization, and Reuse of RTILs as Host Matrix
Se nanoparticles (NPs) of predominantly amorphous phase (?-Se) have been prepared in room-temperature ionic liquids (RTILs). The effects of ion-pair combination and ?OH functionalization of RTILs on the size and phase stability of Se NPs were investigated. The RTILs used were 1-ethyl-3-methyl imidazolium boron tetrafluoride ([EMIM][BF4]), 1-(2-hydroxyethyl)-3-methyl imidazolium boron tetrafluoride ([EOHMIM][BF4]), and 1-ethyl-3-methyl imidazolium methane sulfonate ([EMIM][MS]). The size of Se NPs@[EOHMIM][BF4] was found to be the smallest (?32 nm), followed by Se NPs@[EMIM][BF4] (?57 nm) and Se NPs@[EMIM][MS] (?60 nm), respectively. Interestingly, the stability studies revealed minimal size variations for Se NPs@[EMIM][MS], followed by Se NPs@[EOHMIM][BF4] and Se NPs@[EMIM][BF4], respectively. The observed trends could be correlated with the strength of interionic interactions in the respective RTILs, as well as their packing order (density). Importantly, the RTILs played the role of a solvent, a stabilizer, and an in situ source of reducing species. Pulse radiolysis study revealed imidazolium-originated radical species-driven formation of Se NPs. Further, anticancer efficacy studies demonstrated the role of NP size, wherein Se NPs@[EOHMIM][BF4] exhibited the highest cancer cell killing, followed by Se NPs@[EMIM][BF4] and Se NPs@[EMIM][MS]. Another significant highlight of this work is the reuse of the spent RTILs for the synthesis of the next batch of Se NPs. 2021 American Chemical Society -
Study to assess attitudes towards statistics of business school students: An application of the SATS-36 in India
Students attitudes towards Statistics are pivotal to their learning process as positive attitudes lead to highly satisfactory course achievement and lead to positive outcomes outside class as well. In this paper we are exploring the perception of students of management apropos Statistics, familiarity with which is imperative in todays world of Analytics. The quantitative approach was used to compare attitudes of the students using the two versions of the SATS-36 instrument validated and copyrighted by Candace Schau. A Google form was used to collect responses and was sent to all the students who were enrolled in the Business Statistics course. 172 students responded for the pre-test study while 71 students responded for the post-test study. Data was analysed to see if gender, specialisation choices and previous math experiences accounted for differences in perceptions towards Statistics. It was found that students overall perception of statistics is positive and surprisingly they were more positive towards the beginning of the semester. These results are important as they can lead towards understanding of business students attitudes towards statistics and a way to refine the teaching learning process so that students are in a strong position to exploit the supply demand gap in the Analytics domain and deliver value to organisations. 2021 Eskisehir Osmangazi University. All rights reserved. -
Hybrid models for intraday stock price forecasting based on artificial neural networks and metaheuristic algorithms
Stock market prediction is one of the critical issues in fiscal market. It is important issue for the traders and investors. Artificial Neural Networks (ANNs) associated with nature inspired algorithms are playing an increasingly vital role in many areas including medical field, security systems and stock market. Several prediction models have been developed by researchers to forecast stock market trend. However, few studies have focused on improving stock market prediction accuracy especially when utilizing artificial neural networks to perform the analysis. This paper proposed nine new integrated models for forecasting intraday stock price based on the potential of three ANNs, Back Propagation Neural Network (BPNN), Radial Basis Function Neural Network (RBFNN), Time Delay Neural Network (TDNN) and nature inspired algorithms such as Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC).The developed models were named as GA-BPNN, PSO-BPNN, ABC-BPNN, GA-RBFNN, PSO-RBFNN, ABC-RBFNN, GA-TDNN, PSO-TDNN and ABC-TDNN. Nature inspired algorithms are employed for optimizing the parameters of ANNs. Technical indicators calculated from historical data are fed as input to developed models. Proposed hybrid models validated on four datasets representing different sectors in NSE. Four statistical metrics, Root Mean Square Error (RMSE), Hit Rate (HR), Error Rate (ER) and prediction accuracy were utilized to gauge the performance of the developed models. Results proved that the PSO-BPNN model yielded the highest prediction accuracy in estimating intraday stock price. The other models, GA-BPNN, ABC-BPNN, GA-RBFNN, PSO-RBFNN, ABC-RBFNN, GA-TDNN, PSO-TDNN and ABC-TDNN produced lower performance with mean prediction accuracy of 97.24%, 98.37%, 84.01%, 85.15%, 84.01%, 83.87%, 89.95% and 78.61% respectively. 2021 -
The COVID-19 vaccine preference for youngsters using promethee-ii in the ifss environment
Extensive decision-making during the vaccine preparation period is unpredictable. An account of the severity of the disease, the younger people with COVID-19 comorbidities and other chronic diseases are also at a higher risk of the COVID-19 pandemic. In this research article, the preference ranking structure for the COVID-19 vaccine is recommended for young people who have been exposed to the effects of certain chronic diseases. Multiple Criteria Decision-Making (MCDM) approach effectively handles this vague information. Furthermore, with the support of the Intuitionistic Fuzzy Soft Set (IFSS), the entries under the new extension of the Preference Ranking Organization Method for Enrichment Evaluation-II (PROMETHEE-II) is suggested for Preference Ranking Structure. The concept of intuitionistic fuzzy soft sets is parametric in nature. IFSS suggests how to exploit an intuitionistic ambiguous input from a decision-maker to make up for any shortcomings in the information provided by the decider. The weight of the inputs is calculated under the Intuitionistic Fuzzy Weighted Average (IFWA) operator, the Simply Weighted Intuitionistic Fuzzy Average (SWIFA) operator, and the Simply Intuitionistic Fuzzy Average (SIFA) operator. An Extended PROMETHEE-based ranking, outranking approach is used, and the resultant are recommended under the lexicographic order. Its sustainability and feasibility are explored for three distinct priority structures and the possibilities of the approach. To demonstrate the all-encompassing intuitionistic fuzzy PROMETHEE approach, a practical application regarding COVID-19 severity in patients is given, and then it is compared to other existing approaches to further explain its feasibility, and the sensitivity of the preference structure is examined according to the criteria. 2021 by the authors. Licensee MDPI, Basel, Switzerland. -
Effect of Non-inertial Acceleration on BrinkmanBard Convection in Water-Copper Nanoliquid-Saturated Porous Enclosures
In the present paper we have considered rotating porous tall, square and shallow enclosures heated from below. Linear and non-linear analyses are made using a minimal representation by Fourier trigonometric series. The study is done for realistic boundary condition. Thermophysical properties of water-copper nanoliquid as a function of properties of water as base liquid, copper as nanoparticle and 30% glass fiber reinforced polycarbonate as porous medium are obtained from either phenomenological laws or mixture theory. Non-existence of oscillatory convection is discussed. The range for the existence of unicellular convection is mentioned. The effects of Brinkman number (?), porous parameter (?2), aspect ratio (A) and volume fraction (?) in the presence of rotation on the onset of convection and heat transfer are studied and illustrated graphically. The analytically intractable Lorenz model is derived and transformed into the tractable GinzburgLandau equation using the multiscales method. The definition of Ozoe heat transfer parameter is introduced to discuss the rate of heat transfer enhancement or reduction. It is observed that Ta, ? and ?2 have stabilizing effect on the system and thereby leading to diminished heat transfer whereas A and ? have destabilizing effect on the system and thereby leading to increased heat transfer. Among the three enclosures considered in the study enhanced heat transfer takes place in tall enclosure followed by square and shallow enclosures respectively. It is further observed that presence of nanoparticles advances the onset of convection and enhances the heat transfer. The results of the paper are compared with previous existing results in the absence of rotation and the good agreement is found between them. 2021, The Author(s), under exclusive licence to Springer Nature India Private Limited. -
Multilayer flow and heat transport of nanoliquids with nonlinear Boussinesq approximation and viscous heating using differential transform method
Multilayer fluid flow models are significant in various applications, namely, cooling electronic systems, solar thermal systems, and nuclear reactors. The density of a fluid fluctuates nonlinearly due to large temperature difference circumstances in thermal systems. Thus, the linear Boussinesq approximation is no longer relevant. Therefore, this article describes a multilayer flow of nanoliquids in the presence of nonlinear Boussinesq approximation. The hybrid nanoliquid layer is sandwiched between two nanoliquid layers. The single-phase khanafer-vafai-lightstone model is implemented to simulate the nanoliquids. The quadratic density temperature fluctuation and viscous heating are taken into account. The temperature and velocity across the interface are assumed to be continuous. The equations that govern the problem are solved analytically by using the differential transformation method. The results show that the presence of a hybrid nanoliquid layer affects the velocity and heat transfer properties of the nanofluid flow. Hybrid nanofluid can be used to achieve the desired multilayer flow properties of a nanofluid and its heat transfer properties. Further, the quadratic convection aspect increases the velocity distributions. 2021 Wiley Periodicals LLC -
An analysis of the ethical challenges of blockchain-enabled E-healthcare applications in 6G networks
Developments in blockchain technology coupled with rapid developments in network technologies have disrupted traditional business and service models. One such application is in the domain of healthcare. However, the domain's sensitive nature and complexity require blockchain-enabled e-healthcare to ensure utilitarianism while suitably addressing the associated ethical challenges. In this milieu, the paper attempts to identify and evaluate the parameters of ethical challenges associated with blockchain adoption in e-healthcare. This paper contributes to the extant body of knowledge by presenting a critical review of the ethical considerations at the meso level of blockchains in e-healthcare. Based on findings from the literature, the study identified nine parameters of blockchain ethics. Of these, Accuracy and Right to be Forgotten were found to be most critical in terms of ethical dilemmas in healthcare applications. No evidence of ethical dilemma could be found with respect to Accountability and Data Ownership. As these services are deployed over networks, all these challenges are further evaluated in the context of 6G network-based models. This will not only provide the stakeholders with a holistic view of the ethical challenges in various blockchain-enabled healthcare applications but also enable a meticulous transition to the 6G network. 2021 -
Tamarindusindica Mediated Combustion Synthesis of BiOCl: Photocatalytic Degradation of Dyes and Synthesis of ?-Enaminones
Environmental pollution due to dyes has been increasing continuously due to the large number of textile industries, which affects living systems. Photocatalytic degradation (PCD) is one of the most efficient methods to expel organic dyes in wastewater. In this respect, synthesizing photocatalytic nanoparticles to degrade organic dyes by a simple and cost-effective method is the real challenge. In this article, a carcinogenic dye, methylene blue, is considered for our study as it releases highly toxic species into the ecosystem and causes severe health problems such as cancer, skin and kidney problems, etc. Bismuth oxychloride has been synthesized by simple, low cost and rapid combustion method using low cost, easily available Tamarindusindica as a fuel at 500 C for ~10 min. The obtained BiOCl has been characterized by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), UV-Vis spectroscopy, photoluminescence spectroscopy and surface area by BrunauerEmmettTeller (BET). The XRD pattern shows a tetragonal phase and the FT-IR spectrum shows the presence of Bi-Cl at 1109 cm?1. SEM shows a flake-like morphology and HR-TEM displays d-spacing values of 0.13 nm. Photoluminescence studies show a green emission peak at 530 nm. Synthesis of ?-enaminones was also examined using analogues of aniline and dimedone in presence of BiOCl as a photocatalyst. 2021, The Minerals, Metals & Materials Society. -
Transition metal oxides in electrochemical and bio sensing: A state-of-art review
This review article portrays the progress in developing novel electrochemical sensors using morphologically varied transition metal oxides. The role and applications of transition metal oxide nanoparticles of iron, titanium, manganese, zirconium, cobalt, nickel and their composites in the field of electrochemical and bio sensing are conferred in detail. Appropriate chemical functionalization of these nanomaterials guarantees the selective and sensitive determination of target molecules including DNA or creating antigen/antibody complexes. Substantial data is summed up in the tables. This review article highlights the significance of transition metal oxide nanoparticles as promising electrode modifiers for fabrication of sensors. The review ends up with a relevant discussion, existing challenges and future scopes. 2021 The Author(s) -
Molecularly Imprinted Scaffold Based on poly (3-aminobenzoic acid) for Electrochemical Sensing of Vitamin B6
Inadequate or excess consumption of Vitamin B6 (Vit B6) can have ill effects on the overall well-being of humans, thereby making it necessary to control their content and composition in the food we consume. A simple sensor is fabricated in this work for Vit B6 detection based on employing an electropolymerized molecularly imprinted polymer (MIP) of 3-amino benzoic acid. The poly (3- aminobenzoic acid) (P-(3ABA)) film was electrodeposited by potentiodynamic cycling of potential with and without Vit B6 (template) on carbon fiber paper electrode (CFP). The modified working electrodes were characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Field emission scanning microscopy, Energy dispersive X-ray spectrometry, Fourier Transform Infrared spectroscopy, Optical profilometry and X-ray photon electron spectroscopy were used for characterization. Nyquist plots revealed least charge transfer resistance at MIP/CFP than other control electrodes due to the molecularly imprinted sites. Under the optimized experimental conditions the developed MIP sensor showed a linear range 0.6 ?M to 700 ?M, with a detection limit of 0.010 ?M. Also a value of the imprinting factor (? = 3.50) indicates very good selectivity of the prepared sensor towards Vit B6 detection over its structurally similar analogues in the analysis of real sample matrices. 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. -
Effects of Variable Viscosity and Internal Heat Generation on RayleighBard Convection in Newtonian Dielectric Liquid
The onset of RayleighBard convection of variable-viscosity Newtonian dielectric liquid confined between two parallel plates is subject to free-free isothermal boundary condition. The combined and individual effects of temperature-dependent and electric-field-dependent variable-viscosity along with the internal heat generation are studied using the higher order Galerkin technique. This theoretical study shows that even a mild temperature-dependent variable-viscosity destabilizes the system and the electric-field-dependent variable-viscosity stabilizes the system both in the absence/presence of heat source/sink. 2021, The Author(s), under exclusive licence to Springer Nature India Private Limited. -
Influence of hydrothermal synthesis conditions on lattice defects in cerium oxide
Cerium oxide makes one of the most promising materials for chemical transformations in environmental and energy applications. Herein, the influence of hydrothermal conditions on the physico-chemical characteristics of cerium oxide prepared from salt solution via ammonia precipitation is analyzed. The systems are well characterized using SEM, TEM, XRD analysis, photoluminescence spectra, Raman spectra, TPR study. and XPS analysis. Normal aqueous conditions lead to particles of size ~8 ?nm, with truncated octahedral geometry, closer to spheroid shape (RT-Ce) bound by {111} and {100} planes. Elevated temperature facilitated preferential exposed {100} plane bounded cubic ceria structures of size ~15 ?nm (HT-Ce), which are stabilized by more number of anion vacancies. Low temperature synthesis yielded smaller sized particles with less crystallinity and higher surface area, when compared to hydrothermal route. Lattice defects, represented in terms of Ce3+ ions and associated lattice oxygen vacancies are seen in higher amounts in ceria synthesised via hydrothermal path, as supported by various characterization results. CeO2 achieved via hydrothermal path exhibited higher catalytic oxidation activity, which is examined using a model oxidation reaction, vis., CO oxidation. The enhanced activity of HT-Ce is explained through the defect structure induced facile redox shift in the system. 2021 Elsevier Inc. -
Significance of inclined magnetic field on nano-bioconvection with nonlinear thermal radiation and exponential space based heat source: a sensitivity analysis
The characteristics of heat transport in nanoliquids under the influence of bio-convection (motile microorganism) have significant applications, since nanoliquids have greater capacity to improve heat transport properties than conventional liquids. With these incredible nanoliquid characteristics, the main objective of current research is to examine the impact of the exponential heat source linked to space and the inclined magnetic force on the nano-bioconvective flow between two turntables. The effect of nonlinear thermal radiation, variable thermal conductivity and viscosity aspects are also considered. The complicated nonlinear problem is treated numerically by using Finite difference method. Optimization procedure implemented via Response surface Methodology for the effective parameters thermophoresis parameter, Hartmann number and radiation parameter on the heat transfer rate. The axial velocity is a dwelling function of the inclined angle of the magnetic field, and the variable viscosity parameter. The temperature profile hikes with an exponential space-related heat source and thermal radiation aspects. Also, the heat transport rate is highly sensitive towards nonlinear thermal radiation parameter compared to the thermophoresis effect and Hartmann number. 2021, The Author(s), under exclusive licence to EDP Sciences, SocietItaliana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature.