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1.
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
2.
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
3.
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
4.
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).

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