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2.
RSC Adv ; 13(37): 26134-26143, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37664211

RESUMO

We investigated the physical behavior of SrMO3 (M = Hf and Pt) compounds, which are strontium-based oxide perovskites. We utilized the WIEN2k software to simulate and investigate their physical properties. The structural stability of SrHfO3 and SrPtO3 was verified using the Birch-Murnaghan equation of states for optimization. We also checked the elastic stability through the computation of elastic constants using the IRelast software. Our results indicate the stability of these compounds and showed their anisotropic, ductility, scratch-resistive, and plastic strain-resistant characteristics. Using the TB-mBJ potential approach, we determined that SrHfO3 is an insulator, whereas SrPtO3 is a metal in nature. The density of states computations was used to find the band structure as well as the contribution of different electronic states. Optical property research was conducted using the band gap energies of these substances. Our findings suggest that these crystals have low energy absorption and reflectivity of up to 65%, making them suitable for use in high-frequency UV devices. Specifically, SrHfO3 is more transparent before the energy point 2.80 eV, while the compound SrPtO3 after 6.50 eV to 12.0 eV and SrHfO3 from 12.0 and 14.0 eV. This study represents the first DFT-based investigation of these discussed crystals according to the best of our knowledge.

4.
Heliyon ; 9(8): e18672, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576213

RESUMO

This work reported to investigate convective flow of non-Newtonian fluid effect on an exponentially stretchable surface. Effect of nanoparticle is considered in heat and mass equation. The transformation technique utilized on dimensionless equations is converted to non-dimensionless equations are solved thought numerical approach Bvp4c. Influence of approatiate analysis of velocities, heat and mass transport are scrutinized through figures. Furthermore, the comparative analysis of drag forces, Nusselt number and Sherwood number are evaluated over and done with tabulated values. It is give details that the temperature field strengthens with intensification in thermophoresis and random diffusions. Similarly, rises in thermophoresis effect parameter both temperature and concentration profile increasing.

5.
Heliyon ; 9(7): e17665, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37455986

RESUMO

The purpose of the present research is to conduct an examination of entropy generation in a 2D magneto Williamson hybrid nanofluid flow that contains cobalt ferrite and titanium oxide nanoparticles and undergoes surface-catalyzed reactions through a thin vertical needle. The consequences of joule heating and viscous dissipation are considered to elaborate the features of heat transport. Further, the influence of thermal stratification, thermal radiation, and homogeneous-heterogeneous reaction is also taken into account. Through the application of appropriate similarity variables, the dimensionless system of coupled ordinary differential equations is achieved. The coupled system of equations is numerically solved by the usage of the bvp4c technique in the MATLAB algorithm. The current investigation also compared the existing outcomes with the available literature, which shows great harmony between the two. The consequences of the physical parameters are discussed graphically and with numerical data. It is worth noting that larger values of homogeneous reaction strength and the surface-catalyzed parameter diminish the concentration field. Further, the velocity distribution and their related momentum boundary layer thickness, diminishes with the enlargement of the Weissenberg parameter.

6.
Diagnostics (Basel) ; 13(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37296738

RESUMO

COVID-19, continually developing and raising increasingly significant issues, has impacted human health and caused countless deaths. It is an infectious disease with a high incidence and mortality rate. The spread of the disease is also a significant threat to human health, especially in the developing world. This study suggests a method called shuffle shepherd optimization-based generalized deep convolutional fuzzy network (SSO-GDCFN) to diagnose the COVID-19 disease state, types, and recovered categories. The results show that the accuracy of the proposed method is as high as 99.99%; similarly, precision is 99.98%; sensitivity/recall is 100%; specificity is 95%; kappa is 0.965%; AUC is 0.88%; and MSE is less than 0.07% as well as 25 s. Moreover, the performance of the suggested method has been confirmed by comparison of the simulation results from the proposed approach with those from several traditional techniques. The experimental findings demonstrate strong performance and high accuracy for categorizing COVID-19 stages with minimal reclassifications over the conventional methods.

8.
Molecules ; 28(9)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37175286

RESUMO

This work describes an ab initio principle computational examination of the optical, structural, elastic, electronic and mechanical characteristics of aluminum-based compounds AlRF3 (R = N, P) halide-perovskites. For optimization purposes, we used the Birch-Murnaghan equation of state and discovered that the compounds AlNF3 and AlPF3 are both structurally stable. The IRelast software was used to compute elastic constants (ECs) of the elastic properties. The aforementioned compounds are stable mechanically. They exhibit strong resistance to plastic strain, possess ductile nature and anisotropic behavior and are scratch-resistant. The modified Becke-Johnson (Tb-mBJ) approximation was adopted to compute various physical properties, revealing that AlNF3 and AlPF3 are both metals in nature. From the density of states, the support of various electronic states in the band structures are explained. Other various optical characteristics have been calculated from the investigations of the band gap energy of the aforementioned compounds. These compounds absorb a significant amount of energy at high levels. At low energy levels, the compound AlNF3 is transparent to incoming photons, whereas the compound AlPF3 is somewhat opaque. The examination of the visual details led us to the deduction that the compounds AlNF3 and AlPF3 may be used in making ultraviolet devices based on high frequency. This computational effort is being made for the first time in order to investigate the aforementioned properties of these chemicals, which have yet to be confirmed experimentally.

9.
Heliyon ; 9(3): e14635, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36994385

RESUMO

Renewable energy has been seen as a viable solution to the problems of environmental degradation and the energy crisis. This study examines the long - and short-run linkages between economic globalization, foreign direct investment (FDI), economic growth, and renewable electricity consumption in China's Belt and Road Initiative (BRI) countries. Therefore, this study uses the Pooled Mean Group (PMG) autoregressive distributed lag (ARDL) technique to measure the relationship between constructs based on data collected from 2000 to 2020. The overall results show the collaborative integration of Belt and Road (BRI) countries in terms of globalization, economic growth, and renewable electricity utilization. The results show that there is a long-term positive relationship between FDI and renewable electricity consumption, but a negative relationship in the short term. Furthermore, economic growth is positively correlated with renewable electricity consumption in the long run and negatively correlated in the short run. This study suggests that the governments of BRI countries should encourage globalization by improving technology and knowledge related to renewable electricity consumption in all areas.

10.
Sci Rep ; 13(1): 2677, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792641

RESUMO

Remarkable advancement in wave energy conversion technology has taken place in recent years. Due to its simplicity, the Wells turbine has been one of the most widely used power take-off mechanisms in an oscillating water column type wave-energy conversion device. However, the turbine suffers from several challenges due to its narrow operating range, which hinders the commercial feasibility of the system. Several aerodynamic applications have successfully used passive control methods to modify the flow conditions. This work applied a combination of stall fences and casing grooves for passive flow control of a Wells turbine. The computational fluid dynamics (CFD) technique is used to analyze the modified turbine numerically. The casing groove modified the tip-leakage vortices, interacted with local vortices created by the stall fences, and helped reattach the flow at higher flow coefficients. As a result, the modified turbine increases the operating range up to 33.3%. In addition, the peak-to-average (PTA) power ratio decreased by up to 27.7%.

11.
Comput Biol Med ; 151(Pt A): 106250, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36368110

RESUMO

Motility is defined as the movement of cells by some form of self-propulsion. Some organisms motile by using long flagella that quickly rotate to propel them over various surfaces (in swarming and swimming mechanism), while few motile without the aid of flagella (in twitching, sliding and gliding mechanism). Among these modes, gliding motility is adopted by a rod-shaped organism famously known as gliding bacteria. It is hypothesized that in such type of motility, organism motile under their own power by secreting a layer of slime on the substrate. In this study, an active wall is considered as a substrate and a two-dimensional wavy sheet as an organism. Slip effects are also employed in the current work. The physical properties of the slime are governed by a suitable constitutive equation of couple stress model. A sixth order BVP is obtained by utilizing lubrication assumption. For an appropriate fixed pair of flow rate and organism speed the BVP is solved by MATLAB built-in function bvp-5c. This solution is utilized in the mechanical equilibrium conditions which are obviously not satisfied yet. To satisfy these conditions, the pair of flow rate and gliding speed is refined by a root finding algorithm (modified Newton-Raphson method). By employing this numerical scheme, various figures are shown to demonstrate the effect of several associated parameters on organism speed, flow rate, energy expended by the glider, streamlines and longitudinal velocity. It is observed from the graphical results that organism speed and energy consumption is directly proportional to the couple stress parameter and slip effects.


Assuntos
Algoritmos , Movimento , Cinética
12.
Sci Rep ; 12(1): 17170, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229498

RESUMO

According to research, exposing a person to a magnetic field enhances blood flow and minimizes their risk of suffering a heart attack. Ferrohydrodynamics is the study of fluid motion mechanics that is affected by strong magnetic polarisation forces (FHD). Ferrofluids may transmit heat in a variety of ways by using magnetic fluids. This behaviour is demonstrated by liquid-cooled speakers, which utilise less ferrofluid to prevent heat from reaching the speaker coil. This modification boosts the coil's ability to expand, which enables the loudspeaker to create high-fidelity sound. It is investigated how the fluid dynamics of spinning, squeezing plates are affected by thermosolutal convection and a magnetic field dependent (MFD) viscosity. Standard differential equations are used to represent the equations of the modified form of Navier Stokes, Maxwell's, and thermosolutal convection. The magnetic field, modified velocity field equations, and thermosolutal convection equations all yield suitable answers. Additionally computed and thoroughly detailed are the MHD torque and fluid pressure that are imparted to the top plate. To create a technique with quick and certain convergence, the resulting equations for uniform plates are solved using the Homotopy Analysis Method (HAM) with appropriate starting estimates and auxiliary parameters. The validity and reliability of the HAM outcomes are shown by comparing the HAM solutions with the BVP4c numerical solver programme. It has been found that a magnetic Reynolds number lowers the temperature of the fluid as well as the tangential and axial components of the velocity field. Additionally, when the fluid's MFD viscosity rises, the axial and azimuthal components of the magnetic field behave in opposition to one another. This study has applications in the development of new aircraft take-off gear, magnetorheological airbags for automobiles, heating and cooling systems, bio-prosthetics, and biosensor systems.


Assuntos
Convecção , Hidrodinâmica , Coloides , Humanos , Campos Magnéticos , Modelos Teóricos , Reprodutibilidade dos Testes , Viscosidade
13.
Sci Rep ; 12(1): 15085, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064861

RESUMO

Nanomaterials have achieved remarkable importance in cooling small electronic gadgets like akin and microchips devices. The role of nanoparticles is essential in various aspects, especially in biomedical engineering. Thus hybrid nanomaterials is introduced to strengthen the heat exchangers' performance. In view of the above practical and existing applications of nanomaterials. Our aim is to examine the consequences of Darcy-Forchheimer's radiative and Hall current flow of nanomaterials over a rotating porous disk with variable characteristics. Stretching disk accounting for the slip condition. Nanoparticles ZnO and CoF2O4 are dispersed in based fluid water. The present model is utilized for thermo-physical attributes of hybrid nanomaterials with the impact of shape factor. Transformations convert the modeled PDEs into ODEs. The obtained highly non-linear system is tackled numerically by the NDSolve technique through the software Mathematica. The outcomes of significant variables against different profiles are executed and elaborated in detail. Obtained results show that both nano and hybrid nanofluid radial velocity have reverse behavior against variable porosity and permeability parameters, whereas it decays for larger Forchheimer numbers. Further, it is worthy to point out that, hybrid nanophase has a higher impact on distinct profiles when compared with nano and common liquid phases.

14.
Sci Rep ; 12(1): 16376, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180484

RESUMO

Climate change policy has several potential risks. The purpose of this study is to investigate the impact of green technology development, green energy consumption, energy efficiency, foreign direct investment, economic growth, and trade (imports and exports) on greenhouse gas (GHG) emissions in South Asia from 1981 to 2018. We employed Breusch Pagan LM, bias-corrected scaled LM, and Pesaran CD as part of a series of techniques that can assist in resolving the problem of cross-sectional dependence. First and second generation unit root tests are used to assess the stationarity of the series, Pedroni and Kao tests are used to test co-integration. The long-term associations are examined using fully modified ordinary least square (FMOLS) and panel dynamic ordinary least square (DOLS) for robustness. The results revealed that trade, growth rate, and exports significantly increase GHG emissions. This accepted the leakage phenomenon. The results also demonstrated that green technology development, green energy consumption, energy efficiency, and imports all have a significant negative correlation with GHG emissions. Imports, advanced technical processes, a transition from non-green energy to green energy consumption, and energy efficiency are thus critical components in executing climate change legislation. These findings highlight the profound importance of green technology development and green energy for ecologically sustainable development in the South Asian countries and act as a crucial resource for other nations throughout the world when it comes to ecological security. This research recommends the consumption of environmentally friendly and energy-efficient technologies in order to mitigate climate change and the government's implementation of the most recent policies to neutralize GHG emissions in order to achieve sustainable development.


Assuntos
Desenvolvimento Econômico , Gases de Efeito Estufa , Ásia , Dióxido de Carbono/análise , Mudança Climática , Conservação de Recursos Energéticos , Estudos Transversais , Investimentos em Saúde , Energia Renovável , Tecnologia
15.
ACS Omega ; 7(29): 25309-25320, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35910125

RESUMO

During thermal radiation treatments, heat therapies, and examination procedures like scans and X-rays, the cylindrical blood vessels may get stretched; meanwhile, the blood flow through those blood vessels may get affected due to temperature variations around them. To overcome this issue, this work was framed to explore the impact of heat transmission in a Carreau fluid flow (CFF) through a stretching cylinder in terms of the nonlinear stretching rate and irregular heat source/sink. Temperature-dependent thermal conductivity and thermal radiation are taken into consideration in this study. To tranform complicated partial differential equations into ordinary differential equations, appropriate similarity variables are used. For a limited set of instances, the derived series solutions are compared to previously published results. For linear and nonlinear stretching rates, graphs and tables are used to examine the influence of an irregular heat source/sink on fluid movement and heat transfer. The research outcomes demonstrate that the heat source and nonlinear stretching rate cause a disruption in the temperature distribution in the fluid region, which can alter the blood flow through the vessels. In all conditions except for the heat in an internal heat sink, the nonlinear stretching situation improves the velocity and heat profile. Furthermore, with the increase in the values of the Weissenberg number, the temperature profile shows opposing features in a shear-thickening fluid and shear-thinning fluid. For the former n > 1, the blood fluidity gets affected, restricting the free movement of blood. For the latter, n < 1, the phenomenon is reversed. Other industrial applications of this work are wire coating, plastic coverings, paper fabrication, fiber whirling, etc. In all of those processes, the fluid flow is manipulated by thermal conditions.

16.
Sci Rep ; 12(1): 14679, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36038606

RESUMO

The study of hydromagnetic mixed convection flow of viscoelastic fluid caused by a vertical stretched surface is presented in this paper. According to this theory, the stretching velocity varies as a power function of the displacement from the slot. The conservation of energy equation includes thermal radiation and viscous dissipation to support the mechanical operations of the heat transfer mechanism. Through the use of an adequate and sufficient similarity transformation for a nonlinearly stretching sheet, the boundary layer equations governing the flow issue are converted into a set of ordinary differential equations. The Keller box technique is then used to numerically solve the altered equations. To comprehend the physical circumstances of stretching sheets for variations of the governing parameters, numerical simulations are made. The influence and characteristic behaviours of physical parameters were portrayed graphically for the velocity field and temperature distributions. The research shows that the impact of the applied magnetic parameter is to improve the distribution of the viscoelastic fluid temperature and reduce the temperature gradient at the border. Temperature distribution and the associated thermal layer are shown to have improved because of radiative and viscous dissipation characteristics. Radiation causes additional heat to be produced in liquid, raising the fluid's temperature. It was also found that higher velocities are noticed in viscoelastic fluid as compared with Newtonian fluid (i.e., when K = 0).

17.
ACS Omega ; 7(25): 21574-21582, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35785323

RESUMO

Valorization of waste such as waste tires offers a way to manage and reduce urban waste while deriving economic benefits. The rubber portion of waste tires has high potential to produce pyrolysis fuels that can be used for energy production or further upgraded for use as blend fuel with diesel. In the preset work, waste tire oil (WTO) was produced from the pyrolysis of waste tires in an electric heating furnace at 500-550 °C in the absence of oxygen. Pyrolysis (in nitrogen) and oxidation (in air) of the obtained WTO sample were then performed in a thermogravimetric (TG) furnace that was connected to a Fourier transform infrared cell where the evolved gases were analyzed. The WTO sample was heated up to 800 °C in the TG furnace where the temperature of the sample was ramped up at three heating rates, namely, 5, 10, and 20 °C/min. The TG mass loss and differential thermogravimetric mass loss plots were used to analyze the thermal degradation pathways. Kinetic analysis was performed using the distributed activation energy model to estimate the activation energies along the various stages of the reaction. The pollutant gases, namely, CO2, CO, NO, and H2O, formed during WTO oxidation were evaluated by means of the characteristic infrared absorbance. The functional groups evolved during pyrolysis, namely, alkanes, alkenes, aromatics, and carbonyl groups, were also analyzed. The obtained information can be used for the better design of gasifiers and combustors, to ensure the formation of high-value gaseous products while reducing the emissions. The utilization of waste tires by producing pyrolysis oils thus offers a way of tackling the menace of waste tires while acting as a potential energy source.

18.
Sci Rep ; 12(1): 11658, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35804039

RESUMO

The present study probed the creation of heat energy and concentrating into Newtonian liquids across vertical 3D-heated plates. The role of the Soret and Dufour theories in concentrating and energy formulas is discussed. The role of hybrid nanoparticles is introduced to illustrate particle efficiency in terms of solute and thermal energy. It is removed a viscous dissipation process and a changing magnetic field. The proposed approach is motivated by the need to maximize solute and thermal energy uses in biological and industrial domains. The constructed system of (partial differential equations) PDEs includes concentration, momentum, and thermal energy equations within various thermal characteristics. Transformations are used to formulate the system of (ordinary differential equations) ODEs for solution. To assess various features vs various variables, a Galerkin finite element approach is used. Motion into nanoscale components is shown to be smaller than motion into hybrid nanoparticles. Furthermore, fluctuations in heat energy and solute particle counts are seen in relation to changes in Soret, Eckert, magnetic, and Dufour numbers. The basic finding is that the generation of thermal energy for hybridized nanomaterials is much higher.

19.
Sci Rep ; 12(1): 11484, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798787

RESUMO

In solar heating, ventilation, and air conditioning (HVAC), communications are designed to create new 3D mathematical models that address the flow of rotating Sutterby hybrid nanofluids exposed to slippery and expandable seats. The heat transmission investigation included effects such as copper and graphene oxide nanoparticles, as well as thermal radiative fluxing. The activation energy effect was used to investigate mass transfer with fluid concentration. The boundary constraints utilized were Maxwell speed and Smoluchowksi temperature slippage. With the utilization of fitting changes, partial differential equations (PDEs) for impetus, energy, and concentricity can be decreased to ordinary differential equations (ODEs). To address dimensionless ODEs, MATLAB's Keller box numerical technique was employed. Graphene oxide Copper/engine oil (GO-Cu/EO) is taken into consideration to address the performance analysis of the current study. Physical attributes, for example, surface drag coefficient, heat move, and mass exchange are mathematically processed and shown as tables and figures when numerous diverse factors are varied. The temperature field is enhanced by an increase in the volume fraction of copper and graphene oxide nanoparticles, while the mass fraction field is enhanced by an increase in activation energy.

20.
Artigo em Inglês | MEDLINE | ID: mdl-35599290

RESUMO

The usage of waste for the development of sustainable building materials has received an increasing attention in socio-eco-environment spheres. The rice husk ash (RHA) produced during burning of rice husk and the ever-increasing plastic wastes are useless causing detrimental effects on the environment. This research supports the idea of sustainability and circular economy via utilization of waste to produce value-added products. This research explores the potential of waste plastics, RHA, and silica sand as thermoplastic composite materials. The different composite samples were prepared through waste plastics which includes low- and high-density polyethylene and polypropylene with incorporation of RHA and silica sand in proportions. The study investigates the effect of filler/polymer in 30/70, 20/80, and 10/90 (wt. %) on the workability of the developed composite materials. The workability of the composites was found to improve with filler reinforcement. The experimental results showed the maximum density of 1.676 g/cm3 and mechanical strength of 26.39, 4.89, and 3.25 MPa as compressive, flexural, and tensile strengths, respectively. The minimum percentage of water absorption was 0.052%. The wear tests resulted in a minimum abrasive and sliding wear rate of 0.03759 (cm3) and 0.00692 × 10-6 kg/m. The correlations between wear mechanisms and responses were morphologically analyzed. The developed composites verify the feasibility of RHA and plastics waste as a cost effective and environmentally competent product. The results and discussions provided a direction for the future research on sustainable polymeric composite materials.

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