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2.
Sci Rep ; 13(1): 15040, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699944

RESUMO

Transport of heat visualizes a vital role in many industrial developments. Current study is discussing the role of Joule heating, solar thermal radiation, heat generation/absorption, reactions (homogeneous and heterogeneous) with variable thermal conductivity on partially ionized power law material past over a three-dimensional heated stretched surface. The power law model is assumed to have the thermal characteristics of ethylene glycol material. The phenomenon of momentum and energy balance is derived in Cartesian coordinates and developed PD (partial differential)-equations. Swimming pools, solar collectors, food processing, electronic gadgets, cooling systems, magnetic field measurement, computer chips, thermal enhancement, semiconductor characterization, nuclear fusion research and other physical applications are examples of ongoing research. The principle of boundary layer simplified the governing problem. The complex coupled PD (partial differential)-equations have been converted into ordinary differential equations OD (ordinary differential)-equations by using appropriate similarity transformation. The converted boundary value problem is complex and highly nonlinear which does not have the exact solution. The approximate solution is computed numerically via finite element scheme (FES) which is coded in MAPLE 18.0 symbolic package. The convergence of the scheme is established through grid independent survey and the solution is plotted against numerous involved parameters. Thermal performance produced by [Formula: see text]-[Formula: see text]-[Formula: see text]/EG is higher thermal performance produced by [Formula: see text]-[Formula: see text]/EG. Ion slip and Hall forces are responsible for generating Joule heating mechanism that is responsible for reduction of velocity curve and generating shear stresses. Hence, tangential stresses are declined against increasing [Formula: see text] and [Formula: see text].

4.
Eur Phys J Spec Top ; 232(5): 535-546, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36619194

RESUMO

The purpose of the current work is to provide the numerical solutions of the fractional mathematical system of the susceptible, infected and quarantine (SIQ) system based on the lockdown effects of the coronavirus disease. These investigations provide more accurateness by using the fractional SIQ system. The investigations based on the nonlinear, integer and mathematical form of the SIQ model together with the effects of lockdown are also presented in this work. The impact of the lockdown is classified into the susceptible/infection/quarantine categories, which is based on the system of differential models. The fractional study is provided to find the accurate as well as realistic solutions of the SIQ model using the artificial intelligence (AI) performances along with the scale conjugate gradient (SCG) design, i.e., AI-SCG. The fractional-order derivatives have been used to solve three different cases of the nonlinear SIQ differential model. The statics to perform the numerical results of the fractional SIQ dynamical system are 7% for validation, 82% for training and 11% for testing. To observe the exactness of the AI-SCG procedure, the comparison of the numerical attained performances of the results is presented with the reference Adam solutions. For the validation, authentication, aptitude, consistency and validity of the AI-SCG solver, the computing numerical results have been provided based on the error histograms, state transition measures, correlation/regression values and mean square error. Supplementary Information: The online version contains supplementary material available at 10.1140/epjs/s11734-022-00738-9.

5.
ACS Omega ; 7(49): 45654-45664, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36530264

RESUMO

Residues of oxytetracycline (OTC), a veterinary antibiotic and growth promoter, can be present in animal-derived foods; their consumption is harmful to human health and their presence must therefore be detected and regulated. However, the maximum residue limit is low, and consequently highly sensitive and accurate detectors are required to detect the residues. In this study, a novel highly sensitive electrochemical sensor for the detection of OTC was developed using a screen-printed electrode modified with fluorine-doped activated carbon (F-AC/SPE) combined with a novel deep eutectic solvent (DES). The modification of activated carbon by doping with fluorine atoms (F-AC) enhanced the adsorption and electrical activity of the activated carbon. The novel hydrophobic DES was prepared from tetrabutylammonium bromide (TBABr) and a fatty acid (malonic acid) using a green synthesis method. The addition of the DES increased the electrochemical response of F-AC for OTC detection; furthermore, it induced preconcentration of OTC, which increased its detectability. The electrostatic interactions between DES and OTC as well as the adsorption of OTC on the surface of the modified electrode through H-bonding and π-π interactions helped in OTC detection, which was quantified based on the decrease in the anodic peak potential (E pa = 0.3 V) of AC. The electrochemical behavior of the modified electrode was investigated by cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. Under optimum conditions, the calibration plot of OTC exhibited a linear response in the range 5-1500 µg L-1, with a detection limit of 1.74 µg L-1. The fabricated electrochemical sensor was successfully applied to determine the OTC in shrimp pond and shrimp samples with recoveries of 83.8-100.5% and 93.3-104.5%, respectively. In addition to the high sensitivity of OTC detection, the proposed electrochemical sensor is simple, cost-effective, and environmentally friendly.

6.
Sci Rep ; 12(1): 18970, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36347917

RESUMO

The utilization of Fourier's law of heat conduction provides the parabolic partial differential equation of thermal transport, which provides the information regarding thermal transport for the initial time, but during many practical applications, this theory is not applicable. Therefore, the utilization of modified heat flux model is to be used. This work discusses the utilization of non-Fourier heat flux model to investigate thermal performance of tri-hybrid nanoparticles mixture immersed in Carreau Yasuda material past over a Riga plate by using Hamilton Crosser and Yamada Ota models considering the variable thermos-physical characteristics. The phenomenon presenting the transport of momentum and energy are developed in the form of coupled partial differential equations, which are complex and then transformed into ordinary differential equations by using an appropriate transformation. The transformed equations have been tackled numerically via finite element scheme and the authenticity of obtained solution is shown with the help of comparative analysis of present results with those are available in open literature.


Assuntos
Temperatura Alta , Modelos Teóricos , Análise de Elementos Finitos , Condutividade Térmica
7.
Mikrochim Acta ; 189(12): 461, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36416997

RESUMO

A highly sensitive electrochemical sensor using a calix[6]arene/bismuth ferrite/multiwall carbon nanotube-modified fluorine-doped tin oxide electrode (CA6/BFO/MWCNTs/FTO) was fabricated for the detection of methyl parathion. The MWCNTs, BFO, and CA6 were consecutively cast onto the FTO electrode surface to enhance the surface area, electron transfer, and selectivity of sensors. The electrochemical behavior of CA6/BFO/MWCNTs/FTO was studied via cyclic voltammetry and electrochemical impedance spectroscopy. MP was detected via cyclic voltammetry in a phosphate buffer solution at pH 7.0. The working principle of the sensor involves a linear decrease in the anodic peak current of BFO with increasing MP concentration. The linear working ranges are 0.005-0.05 nM and 0.07-1.5 nM. The CA6/BFO/MWCNTs/FTO sensor provides a low detection limit (S/N = 3) of 5 pM and a high electrochemical sensitivity of 1.23 A µM-1 cm-2. The fabricated sensor was successfully applied to assess the presence and amount of MP in vegetables and fruits (recoveries of 82.0-106.8%), with results comparable to high-performance liquid chromatography.


Assuntos
Técnicas Biossensoriais , Metil Paration , Nanotubos de Carbono , Nanotubos de Carbono/química , Flúor , Técnicas Eletroquímicas , Bismuto , Técnicas Biossensoriais/métodos , Eletrodos , Fluoretos
8.
Sci Rep ; 12(1): 13497, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931730

RESUMO

Boosting of thermal transportation is the demand of current era. Several techniques have been used to do so. One of an important way is the mixing of nanoparticles to boost thermal performance. Current investigation has been prepared to study the inclusion of tri hybrid nanoparticles in Prandtl fluid model past over a stretched heated sheet. Modelling of consider problem has been done due to consideration of movement in flow in Cartesian coordinates which results coupled partial differential equation system thermal transport in presented by considering generalized heat flux model and heat generation/absorption. The derived coupled complex partial differential equations (PDEs) system is simplified by engaging boundary layer theory. Such developed model is used in coolants regarding automobiles, dynamics in fuel and production of solar energy, fuel cells, optical chemical sensors, automotive parts, dental products, cancer therapy, electrical insulators and dental products. Handling of complex PDEs for the solution is a challenging task. Due to complexity in computational work these PDEs have been transformed into ordinary differential equations (ODEs) after applying similarity transformation afterwards converted ODEs have been approximated via finite element algorithm coded in MAPLE 18.0 symbolic computational package. Comparative study has been presented for the validity of code and authenticity of obtained result. It is observed that fluid velocity for tri-hybrid nanoparticles is higher than fluidic motion for pure fluid, nanofluid and hybrid nanomaterial.


Assuntos
Nanopartículas , Nanoestruturas , Análise de Elementos Finitos , Modelos Teóricos , Movimento (Física)
9.
Sci Rep ; 12(1): 12206, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842471

RESUMO

Flow in a rotating cone for magnetized Prandtl fluid model is inspected in this investigation. The momentum equation of Prandtl model is derived under the consideration of Hall and ion slip effects and heat transport phenomenon is considered with Joule heating and viscous dissipation effects. The model of Hamilton Crosser and Yamada Ota are considered for the empirical relations of nanofluid mixture. The flow presenting expression of Prandtl fluid model with thermal transport is modeled under boundary layer approximation in the form of partial differential equations (PDEs). The derived PDEs have been converted into set of coupled nonlinear ordinary differential equations (ODEs) by engaging an appropriate scaling group transformation and these converted nonlinear set of ODEs have been tackled numerically via finite element scheme (FES). Impact of different emerging parameters has been displayed graphically and the physics behind the observed phenomena is explained in detail. The convergence of FES is established by carrying the grid independent survey. From the performed investigation, it is recorded that the parameters appear due to Hall and Ion slip currents enhance the fluid velocity but the inverse behavior is recorded for temperature profile.

10.
Sci Rep ; 12(1): 10406, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729246

RESUMO

Ethylene glycol is commonly used as a cooling agent in the engine, therefore the study associated with EG has great importance in engineering and mechanical fields. The hybrid nanofluid has been synthesized by adding copper and graphene nanoparticles into the Ethylene glycol, which obeys the power-law rheological model and exhibits shear rate-dependent viscosity. As a result of these features, the power-law model is utilized in conjunction with thermophysical characteristics and basic rules of heat transport in the fluid to simulate the physical situations under consideration. The Darcy Forchhemier hybrid nanofluid flow has been studied under the influence of heat source and magnetic field over a two-dimensionally stretchable moving permeable surface. The phenomena are characterized as a nonlinear system of PDEs. Using resemblance replacement, the modeled equations are simplified to a nondimensional set of ODEs. The Parametric Continuation Method has been used to simulate the resulting sets of nonlinear differential equations. Figures and tables depict the effects of physical constraints on energy, velocity and concentration profiles. It has been noted that the dispersion of copper and graphene nanoparticulate to the base fluid ethylene glycol significantly improves velocity and heat conduction rate over a stretching surface.

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