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Prediction of ground water quality in western regions of Tamilnadu using LSTM network
Assessing and safeguarding groundwater quality is critical for sustaining life in water-scarce regions like western Tamil Nadu. The motivation behind this study stems from the pressing need to address water quality challenges in a region grappling with scarcity. Despite existing efforts, a notable research gap exists in predictive tools that comprehensively capture the nuanced temporal variations and trends in groundwater quality. This is where the LSTM network steps in, showcasing exceptional accuracy in short-term predictions and discerning long-term trends. This research uses Long Short-Term Memory (LSTM) networks, a variant of recurrent neural networks, to predict groundwater quality in South Indian Regions, especially in Tamil Nadu. Extensive data, encompassing parameters such as pH, dissolved oxygen, turbidity, and various chemical constituents, were gathered over an extended timeframe. The LSTM model was then trained on this historical dataset, factoring in temporal dependencies and seasonality inherent in groundwater quality data. The validation process rigorously tests the LSTM model against actual groundwater quality measurements. The results were impressive, as the model demonstrated a remarkable ability to unravel the complex variations in groundwater quality. 2024 Elsevier B.V. -
Studies on the antifungal activity of biotemplated gold nanoparticles over Candida albicans
Green synthesis and applications of gold nanoparticles are more fascinating research area due to their unique optical properties and high X-ray attenuation power. In this study, we have synthesized gold nanoparticles of uniform size (5 nm) with spherical shape. UVvis spectroscopy, Transmission Electron Microscopy and Atomic Force Microscopy were employed to characterize the synthesized gold nanoparticles. The biomedical applications of the synthesized gold nanoparticles were carried out against most prevalent human fungal pathogen, Candida albicans. Broth micro dilution assay was used to determine minimum inhibitory concentration (MIC). We observed that 0. 5 mM concentration was effective in inhibiting the growth of fungal cells which was later confirmed by spot assay. 2019 Elsevier Ltd -
Evaluation of Wound Healing Effect of Curcumin Loaded OPL Carbon Nanospheres Embedded Chitosan Membranes
Biowaste-derived carbon biomaterial scaffolds are being used for wound healing and are the focus of interest. Carbon nanospheres derived from oil palm leaves without any catalysts via pyrolysis were loaded with a traditional drug curcumin. The wound healing scaffolds were fabricated on the PP non-woven fabric support using chitosan as the biopolymer matrix. Prepared carbon nanospheres and the scaffolds were characterized using ATR-IR and FESEM techniques. The wettability of scaffolds was examined to ensure the feasible moisture absorption ability, in vitro drug release profile and in vitro antibacterial activity against two strains of bacteria. The in vivo wound healing feature of scaffolds was studied by excision wound model for MRSA infected wound. Measured wound contraction percentage and the bacterial count on wounds at regular time intervals proved that, the scaffold dressed with chitosan and curcumin loaded carbon nanospheres showed an efficient reconstruction of skin through histopathological investigations. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Changes in wage trends and earnings differences in Kerala /
The Indian Journal of Labour Economics, Vol.61, Issue 4, pp.624-638, ISSN No: 0971-7927. -
Interactions of Environmental Pollutant Aromatic Amines With Photo Excited States of Thiophene Substituted 1,3,4-Oxadiazole Derivative: Fluorescence Quenching Studies
In the present work, the fluorescence quenching of novel thiophene substituted1,3,4-oxadiazole derivative 2-(4-(4-vinylphenyl) phenyl)-5-(5-(4-vinylphenyl)thiophen-2-yl)-1,3,4-oxadiazole (TSO) by five different environmental pollutant aromatic amine derivatives like 2,4-dimethylaniline, 3-chloroaniline, 4-chloroaniline, o-anisidine, and m-toluidine has been studied at room temperature through steady-state and time-resolved methods. It is observed that, the quenching efficiency is highest in the case of o-anisidine and least in the case of 3-chloroaniline. The fluorescence quenching mechanism between TSO and aromatic amines is analysed through different quenching models. The results suggest that, the fluorescence quenching is due to diffusion assisted dynamic or collisional quenching according to the sphere of action static quenching model and according to the finite sink approximation model, the bimolecular quenching reactions are due to the collective effect of dynamic and static quenching. Further, cyclic voltammetry and DFT studies suggest that the fluorescence quenching is due to electron transfer. Binding equilibria analysis confirms the 1:1 stoichiometric ratio between fluorophore and the quencher. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
The diffuse radiation field at high galactic latitudes /
The Astrophysical Journal, Vol.858, Issue 2, pp.1-9, ISSN No: 1538-4357. -
Dynamics of Sutterby fluid flow due to a spinning stretching disk with non-Fourier/Fick heat and mass flux models
The magnetohydrodynamic Sutterby fluid flow instigated by a spinning stretchable disk is modeled in this study. The Stefan blowing and heat and mass flux aspects are incorporated in the thermal phenomenon. The conventional models for heat and mass flux, i.e., Fourier and Fick models, are modified using the Cattaneo-Christov (CC) model for the more accurate modeling of the process. The boundary layer equations that govern this problem are solved using the apt similarity variables. The subsequent system of equations is tackled by the Runge-Kutta-Fehlberg (RKF) scheme. The graphical visualizations of the results are discussed with the physical significance. The rates of mass and heat transmission are evaluated for the augmentation in the pertinent parameters. The Stefan blowing leads to more species diffusion which in turn increases the concentration field of the fluid. The external magnetism is observed to decrease the velocity field. Also, more thermal relaxation leads to a lower thermal field which is due to the increased time required to transfer the heat among fluid particles. The heat transport is enhanced by the stretching of the rotating disk. 2021, Shanghai University. -
Optimized heat transport in Marangoni boundary layer flow of a magneto nanomaterial driven by an exponential interfacial temperature distribution
In a small boundary layer of the fluid interface, the temperature distribution deviates from being linear with the spatial coordinate and exhibits an exponential form. Hence, the Marangoni convective flow of a nanoliquid driven by an exponential interfacial temperature distribution is modeled in this study. Due to practical applicability, the working fluid is chosen to be ethylene glycol-based magnesium oxide nanoliquid, which is modeled using experimentally estimated properties. In the system, the external effects of an inclined magnetism, thermal radiation, and an internal heat source are considered. Heat transport is rigorously analyzed using an empirical model, which is estimated using the robust response surface methodology (RSM) to find the optimal working conditions and to estimate the sensitivity. The modeled problem is simulated numerically using the finite difference-based scheme and a parametric analysis is conducted to study the effect of magnetic field, inclination of magnetic field, radiation, and internal heat source parameters. The internal heat generation (increase of 0.94%) factor dominates the augmentation in the thermal field but at some distance, the thermal radiation factor has a predominant impact (58.99%). The inclination angle of the magnetic field has a prominent decremental impact on the velocity profile. Also, the radiative heat flux enhances the temperature profile. Optimal working conditions are estimated to be with a magnetic inclination of 10 and using a liquid with 0.25% volume fraction of 100 nm. This study finds applicability in crystal growth, drying silicon wafers, and heat exchangers. 2022 Wiley-VCH GmbH. -
Thermo-solutal Marangoni convective assisting/resisting flow of a nanofluid with radiative heat flux: A model with heat transfer optimization
The mixed Marangoni assisting/resisting flow of a nanofluid with thermal radiative heat flux is analyzed when thermal and solutal buoyant forces are significant. The heat and mass transfer rates are simultaneously optimized by utilizing the Response Surface Methodology (RSM). The face-centered Central Composite Design (fc-CCD) is used for the numerical experimental design involved in RSM. The sensitivities of the heat and mass transfer rates are evaluated to compare the impact of the thermal and solutal buoyant forces. Appropriate scaling and similarity transformations are utilized to simplify the problem and then numerical solutions are obtained. The nanoliquid flow, temperature, and concentration profiles are plotted for the buoyancy assisting and opposing Marangoni cases. The Marangoni flow with opposite buoyancy is found to have a greater magnitude of velocity while the flows assisted by the buoyancy have a greater magnitude of temperature and concentration profiles. Thermal buoyancy force has a predominant (0.6%) impact on both heat and mass transfer rates compared to solutal buoyancy force. Buoyancy forces are positively sensitive to heat and mass transfer rates. The thermal radiation aspect augments the temperature profile throughout the domain. The optimized mass and heat transfer rates ((Formula presented.) and (Formula presented.)) is achieved at the highest level of the buoyancy forces and ratio of Marangoni numbers. 2022 Wiley-VCH GmbH. -
Corrigendum to Computational simulation of surface tension and gravitation-induced convective flow of a nanoliquid with cross-diffusion: An optimization procedure [applied mathematics and computation 425 (2022) 127108]
This corrigendum addresses both the physical configuration and certain typographical errors in [1] to improve clarity. These corrections do not impact the originality, results, or mathematical validity of [1]. 2024 -
Heat transfer enhancement using temperature-dependent effective properties of alumina-water nanoliquid with thermo-solutal Marangoni convection: A sensitivity analysis
The sensitivity of the heat transport rate in the thermo-solutal Marangoni convection of Al 2O 3- H 2O nanoliquid at 300K is analyzed. The nanoliquid is modeled using the modified Buongiorno model which incorporates the Brownian motion, effective nanoliquid properties, and thermophoresis effects. The thermophysical models proposed by Khanafer and Vafai are chosen in this analysis as these correlations are in good agreement with the experimental values. External constraining factors like thermal radiation and variable magnetic field are also considered. The basic equations are solved using apposite transformation variables and Finite Difference Method (FDM). The impacts of the effectual parameters on all the profiles are analyzed. Furthermore, the heat transport is analyzed by executing a Response Surface Methodology (RSM) model with the Brownian motion parameter (0.1 ? Nb ? 0.5), thermophoretic parameter (0.1 ? Nt ? 0.5), and nanoparticle volume fraction (1 % ? ?? 3 %). The modified Buongiorno model yields lower temperature and concentration profiles when compared to the conventional Buongiorno model. The heat transfer rate is the most sensitive to the Brownian motion parameter than thermophoresis and nanoparticle (NP) volume fraction parameters. The results of this study would be instrumental in improving the efficiency of the welding process, crystal growth, and coating technologies. 2021, King Abdulaziz City for Science and Technology. -
Computational simulation of surface tension and gravitation-induced convective flow of a nanoliquid with cross-diffusion: An optimization procedure
The control of heat transfer in the hydromagnetic semiconductor crystal involves Marangoni convection with buoyancy forces. In this study, the conventional thermo-solutal Marangoni mixed flow model is modified by incorporating the solutal buoyancy effects that are significant in the flow phenomenon. The heat and mass transfer (HMT) characteristics of the Marangoni convective flow of a Cu ? H2O nanofluid subjected to the assisting/resisting buoyancy forces and cross-diffusion are numerically studied. The homogeneous single-phase nanoliquid model is used in conjunction with experimental data of dynamic viscosity and thermal conductivity. The Dufour and Soret effects are considered. Governing equations are solved using the finite difference-based algorithm. The problem is analyzed in a unified way considering the cases of buoyancy-assisted flow and buoyancy-opposed flow. The response surface methodology (RSM) based on the face-centered composite design (CCD) is used to optimize the heat and mass transfer rates. A multivariate regression model is proposed and authenticated prior to optimization. Additionally, sensitivity analysis is performed using the full quadratic regression model. The increase in the temperature profile is more significant due to the radiative heat flux than the inclined magnetic field. Heat transfer has a high sensitivity to the appearance of thermal radiation, while mass transfer has a high sensitivity to the Soret effect. Simultaneous optimization of HMT rates is achieved with the high level of thermal radiation and low levels of the cross-diffusion aspects. 2022 -
Optimization of heat transfer in the thermal Marangoni convective flow of a hybrid nanomaterial with sensitivity analysis
The heat transfer rate of the thermal Marangoni convective flow of a hybrid nanomaterial is optimized by using the response surface methodology (RSM). The thermal phenomenon is modeled in the presence of a variable inclined magnetic field, thermal radiation, and an exponential heat source. Experimentally estimated values of the thermal conductivity and viscosity of the hybrid nanomaterial are utilized in the calculation. The governing intricate nonlinear problem is treated numerically, and a parametric analysis is carried out by using graphical visualizations. A finite difference-based numerical scheme is utilized in conjunction with the 4-stage Lobatto IIIa formula to solve the nonlinear governing problem. The interactive effects of the pertinent parameters on the heat transfer rate are presented by plotting the response surfaces and the contours obtained from the RSM. The mono and hybrid nanomaterial flow fields are compared. The hybrid nanomaterial possesses enhanced thermal fields for nanoparticle volume fractions less than 2%. The irregular heat source and the thermal radiation enhance the temperature profiles. The high level of the thermal radiation and the low levels of the exponential heat source and the angle of inclination (of the magnetic field) lead to the optimized heat transfer rate (Nux = 7.462 75). 2021, Shanghai University. -
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 -
Inclined magnetic field and nanoparticle aggregation effects on thermal Marangoni convection in nanoliquid: A sensitivity analysis
The heat transfer rate of thermal Marangoni convection in ethylene glycol-based titanium nanoliquid is analyzed by using the Response Surface Methodology (RSM). Two different heat sources (i.e. the temperature-related heat source (THS) and the space-related exponential heat source (ESHS)) are included in the thermal analysis. Aggregation of nanoparticles and inclined magnetism are also considered. The modified Krieger-Dougherty model and the modified Maxwell-Bruggeman model are used to analyze the aggregation aspect of the nanoparticles. The resulting nonlinear system is treated numerically by using the finite difference method. The sensitivity of the heat transfer rate to the thermal radiation parameter, the ESHS parameter, and the THS parameter is examined by using the RSM model. The individual impact of the actual parameters on various flow fields is compared and visualized by graphs. The heat transfer rate is positively sensitive to thermal radiation and negatively sensitive to the parameters of the heat source. Besides, the ESHS aspect has a greater impact on the heat transfer rate than the THS aspect. The velocity flow field is decelerated significantly (5.31%near the interface) by the magnetic field inclination angle. 2020 The Physical Society of the Republic of China (Taiwan) -
Sensitivity analysis of Marangoni convection in TiO2EG nanoliquid with nanoparticle aggregation and temperature-dependent surface tension
The sensitivity analysis of the magnetohydrodynamic thermal Marangoni convection of ethylene glycol (EG)-based titania (TiO2) nanoliquid is carried out by considering the effect of nanoparticle aggregation. The rate of heat transfer is explored by utilizing response surface methodology and estimating the sensitivity of the heat transfer rate toward the effective parameters: radiation parameter (1 ? R ? 3), magnetic parameter (1 ? M ? 3) and nanoparticle volume fraction (1 % ? ?? 5 %). The heat transfer phenomenon is scrutinized with thermal radiation and variable temperature at the surface. The effective thermal conductivity and viscosity with aggregation are modeled by using the MaxwellBruggeman and KriegerDougherty models. The governing equations are solved by using the apposite similarity transformations. It is found that when the effect of aggregation is considered, the velocity profile is lower. A positive sensitivity of the Nusselt number toward thermal radiation is observed. Further, a negative sensitivity of the heat transfer rate is observed toward the magnetic field and nanoparticle volume fraction. 2020, Akadiai Kiad Budapest, Hungary. -
Logistic growth and SIR modelling of coronavirus disease (COVID-19) outbreak in India: Models based on real-time data
The logistic growth model and the Susceptible-Infectious-Recovered (SIR) framework are utilized for the mathematical modelling of the Coronavirus disease (COVID-19) outbreak in India. Karnataka, Kerala and Maharashtra, three states of India, are selected based on the pattern of the disease spread and the prominence in being affected in India. The parameters of the models are estimated by utilizing real-time data. The models predict the ending of the pandemic in these states and estimate the number of people that would be affected under the prevailing conditions. The models classify the pandemic into five stages based on the nature of the infection growth rate. According to the estimates of the models it can be concluded that Kerala is in a stable situation whereas the pandemic is still growing in Karnataka and Maharashtra. The infection rate of Karnataka and Kerala are lesser than 5% and reveal a downward trend. On the other hand, the infection rate and the high predicted number of infectives in Maharashtra calls for more preventive measures to be imposed in Maharashtra to control the disease spread. The results of this analysis provide valuable information regarding the disease spread in India. 2020, International Information and Engineering Technology Association. -
Time-Dependent Nonlinear Convective Flow and Radiative Heat Transfer of Cu-Al2O3-H2O Hybrid Nanoliquid with Polar Particles Suspension: a Statistical and Exact Analysis
The statistical and exact analysis of heat transfer rate and skin friction coefficient of a nonlinear convective flow of Cu ? Al2O3 ? H2O hybrid nanofluid with polar particle suspension is performed. The heat transport phenomenon includes radiative heat effect. A micropolar fluid model is accounted. Exact solutions to the governing problem are found via Laplace transform method (LTM). The heat transfer rate and skin friction are analysed critically via statistical methods like probable error and regression models. The slope of linear regression of data points for skin friction and Nusselt number is estimated to quantify the increase/decrease. The Nusselt number and thermophysical properties for twenty-four different hybrid nanofluids are presented. A novel idea of a nonlinear convective flow of Cu ? Al2O3 ? H2O hybrid nanofluid with polar particle suspension is investigated for the first time. Opposite behaviour of velocity and microrotation profile are established when the physical parameters are varied. 2019, Springer Science+Business Media, LLC, part of Springer Nature. -
Sensitivity analysis of radiative heat transfer in Casson and nano fluids under diffusion-thermo and heat absorption effects
The exact analysis of the magnetohydrodynamic flow of a Newtonian nanofluid past an inclined plate through a porous medium is carried out. The flows of a Newtonian nanofluid and a non-Newtonian Casson fluid are juxtaposed. The heat transport phenomenon is analyzed in the presence of Dufour and heat absorption effects. The Darcy model and Rosseland approximation are employed to simulate the effects of porous media and radiative heat. The exact solutions are obtained by using the Laplace transform method. The effects of different physical parameters on the velocity, temperature and concentration profiles are scrutinized using graphs. Statistical techniques, like the slope of data points, coefficient of correlation, probable error, and multiple linear regression, are employed to analyze the rate of heat transfer and skin friction coefficient. Further, the sensitivity of the skin friction coefficient and Nusselt number are analyzed using the Response Surface Methodology (RSM). The Nusselt number has a positive sensitivity towards thermal radiation, and it is negatively sensitive towards nanoparticle volume fraction and Dufour number. 2019, SocietItaliana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature.