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Because of their thermophysical and rheological properties, graphene oxide (GO) nanofluids show promising advances in heat transfer enhancement. In particular, in magnetohydrodynamic (MHD) studies, where the fluid flow is kept in check, heat transfer tends to diminish due to magnetic field strength. GO nanoparticles, with the highest thermal conductivity, significantly impacts heat transfer devices through conductive heat transfer enhancement. This paper computationally investigates the MHD flow of GO nanofluid over a linearly stretching cylinder. The nanofluid flow is modelled using Buongiorno model under the influence of viscous dissipation effects and the effects of nanoparticle characteristics such as thermophoresis and Brownian motion. The modelled equations are solved using spectral collocation method under isothermal and slip boundary conditions. An examination of the impacts of embedded parameters is presented in detail and it is shown that the conductive heat transfer and diffusive mass transfer are enhanced by dispersing GO nanoparticles in the base fluid. A quantitative analysis is made with the previously published results for special cases. As suggested, this study is significant in heat transfer applications which demand the use of magnetic fields. [ABSTRACT FROM AUTHOR]

The B 3 Π 2 − X 3 Δ 2 (0, 0) band system of the titanium monoxide (TiO) molecule was excited in a DC copper arc with a constant deviation spectrometer. The resulting spectrum has been analyzed using image J software. Relative intensity measurements of the P- and R-branch molecular lines of the (0, 0) band with rotational quantum (J ) numbering have been obtained. The measured intensity of rotational molecular lines and the J numbering were used to estimate the excitation rotational temperature of the source emitting the spectrum of TiO molecules. Also the presence of TiO spectral lines of the B 3 Π 2 − X 3 Δ 2 (0, 0) band in the wavenumber region of 14 500 to 16 000 cm−1 has been confirmed in the umbral spectrum, from the atlases recorded at the National Solar Observatory using the Fourier transform spectrometer (FTS) of the McMath-Pierce Solar Telescope on Kitt Peak. The combined laboratory and sunspot spectral line measurements have been used to obtain the improved molecular structure parameters for the electronic states B 3 Π 2 and X 3 Δ 2 of the TiO molecule. Using equivalent width measurements of well resolved and identified lines in the sunspot spectrum with known rotational quantum number, the effective rotational temperature was found to be 2555 ± 780 K. This proves the presence of TiO molecules in sunspot and other higher temperature astrophysical sources. [ABSTRACT FROM AUTHOR]