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The study of formal logic helps to improve the process of thinking and tries to refine and improve the thinking ability. The objectives of this study are to know the effectiveness of formal logic course and to determine the critical thinking variables that are effective and that are ineffective. A sample of 214 students is selected from all the three departments Engineering, Information Technology and Business department from Nizwa College of Technology, Sultanate of Oman. The analysis revealed that there is no significant relationship between critical thinking variables and formal logic course. It is found that deductive and interpretation skills of the students have increased after the posttest. At the same time, inference skills, assumptions and arguments decreased after the posttest. Assumption skill is found to be the most favourable critical thinking variable.

Polarized emission carries captivating information and can help in understanding various elementary processes involving collisions within the plasma as well as in radiative transitions. In this work, we investigate the spatio-temporal dependence of the emission anisotropy of a nanosecond laser produced aluminium plasma at 100 mbar background pressure. We observe that the anisotropy of the emission spectra exhibits interesting spatio-temporal characteristics, which in turn depends on the charge state of the emitting species. The degree of polarization (DOP) is found to reverse its sign along the plume propagation direction. The observed behaviour in the DOP appears to be due to the contribution from various atomic processes involved. Closer to the sample the contribution from the self-generated magnetic field predominantly affects the polarization. On the other hand, the effect of the self-generated magnetic field on the observed polarized emission is insignificant as the plume propagates away from the sample. This is of particular interest in polarization resolved laser induced breakdown spectroscopy (PRLIBS) as the spatio-temporal profile of the degree of polarization has to be properly taken into account prior to the spectral analysis. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) is a well-established technique widely used in fundamental research and diverse practical fields. Polarization-resolved LIBS, a variant of this technique, aims to improve the sensitivity, which is a critical aspect in numerous scientific domains. In our recent work we demonstrated that the degree of polarization (DOP) in the emission depends on the spatial location and time in a nano second laser generated aluminium plasma1. Present study investigates the effect of polarized emission on the estimation of plasma parameters. The plasma parameters are estimated using the conventional spectroscopic methods such as Boltzmann plot and line intensity ratio for the estimation of electron temperature and Stark broadening for estimating the electron density. The estimated plasma temperature using Boltzmann plot method shows large errors in electron temperature for the locations where DOP is higher. However, the electron density estimated using the Stark width does not show such variation. The observed ambiguity in temperature estimation using the Boltzmann plot method appears to be a consequence of deviation from expected Maxwell Boltzmann distribution of population of the involved energy levels. These findings highlight the need of assessing the DOP of the plasma before selecting the polarization for PRLIBS or temperature estimation using Boltzmann plots in elemental analysis. Figure shows the wavelength dependence of Degree of Polarization (DOP) of Al II emissions lines from different locations within the plasma plume at various time delays. At larger distances (3.5 mm and 4.5 mm), the DOP of emission lines shows a substantial wavelength dependence in comparison to the locations nearer to the sample. [Display omitted] • Dependence of degree of polarization of line emissions from laser produced plasma on emission wavelength • Plasma parameters are estimated using spectroscopic methods. • The estimated temperature from Boltzmann plot method shows significant errors for polarization-resolved data. • Results shows a possible deviation from MB distribution for different energy levels of a given species. • Information of the DOP of the emission is critical for estimation of plasma parameters using spectroscopy. [ABSTRACT FROM AUTHOR]