Tiermomagnetic measurements were conducted on 13 samples of Quaternary volcanic rocks of different episodes from three separate localities by Thellier's method.Paleointensities representing three Quaternary sub-pe...Tiermomagnetic measurements were conducted on 13 samples of Quaternary volcanic rocks of different episodes from three separate localities by Thellier's method.Paleointensities representing three Quaternary sub-periods have been obtained : 0.62 for early Pleistocene, 1.01 far middle Pleistocene and 1.57 for late Pleistocene as relative to today's magnetic field intensity. The results indicate that geomagnetic field intensity has been increasing since Pleistocene, and there exists a close relationship between the variations of paleeintensity and climatic fluctuations, i.e. the climate trends to become colder with increasing paleointensity and it is truc for the oppositc case.展开更多
In this article, we considers the thermodynamics analysis of creeping viscous nanofluid flow in a horizontal ciliated tube under the effects of a uniform magnetic field and porous medium. Moreover, energy analysis is ...In this article, we considers the thermodynamics analysis of creeping viscous nanofluid flow in a horizontal ciliated tube under the effects of a uniform magnetic field and porous medium. Moreover, energy analysis is performed in the presence of an internal heat source and thermal radiation phenomena. The thermal conductivity of base fluid water is strengthened by considering the carbon nanotubes (CNTs). Mathematical formulation operated, results in a set of non-linear coupled partial differential equations. The governed differential system is transformed into an ordinary differential system by considering suitable similarity variables. Exact solutions in the closed form are computed for the temperature, momentum and pressure gradient profiles. In this study, special attention is devoted to the electrical conductivity of the CNTs. Streamlines patterns are also discussed to witness the flow lines for different parameters. Thermodynamics analysis shows that entropy of the current flow system is an increasing function of Brinkmann number, magnetic parameter, nanoparticle concentration parameter and Darcy number.展开更多
文摘Tiermomagnetic measurements were conducted on 13 samples of Quaternary volcanic rocks of different episodes from three separate localities by Thellier's method.Paleointensities representing three Quaternary sub-periods have been obtained : 0.62 for early Pleistocene, 1.01 far middle Pleistocene and 1.57 for late Pleistocene as relative to today's magnetic field intensity. The results indicate that geomagnetic field intensity has been increasing since Pleistocene, and there exists a close relationship between the variations of paleeintensity and climatic fluctuations, i.e. the climate trends to become colder with increasing paleointensity and it is truc for the oppositc case.
文摘In this article, we considers the thermodynamics analysis of creeping viscous nanofluid flow in a horizontal ciliated tube under the effects of a uniform magnetic field and porous medium. Moreover, energy analysis is performed in the presence of an internal heat source and thermal radiation phenomena. The thermal conductivity of base fluid water is strengthened by considering the carbon nanotubes (CNTs). Mathematical formulation operated, results in a set of non-linear coupled partial differential equations. The governed differential system is transformed into an ordinary differential system by considering suitable similarity variables. Exact solutions in the closed form are computed for the temperature, momentum and pressure gradient profiles. In this study, special attention is devoted to the electrical conductivity of the CNTs. Streamlines patterns are also discussed to witness the flow lines for different parameters. Thermodynamics analysis shows that entropy of the current flow system is an increasing function of Brinkmann number, magnetic parameter, nanoparticle concentration parameter and Darcy number.
