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Teaching in Higher Education is with increasing frequency completed within a Learning Management System (LMS) environment in the Blended Learning modality. The use of learning objects (activities and resources) offered by LMS means that both teachers and students require training. In addition, gender differences relating to the number of students in STEM (Science, Technology, Engineering, and Mathematics) and Non-STEM courses might have some influence on the use of those learning objects. The study involves 13 teachers (6 experts in e-Learning and 7 non-experts) on 13 academic courses (4 STEM and 9 Non-STEM) and a detailed examination of the logs of 626 students downloaded from the Moodle platform. Our objectives are: (1) To confirm whether significant differences may be found in relation to the use of learning objects (resources and activities) on Moodle, depending on the expertise of the teacher (expert vs. non-expert in e-Learning); (2) To confirm whether there are significant differences between students regarding their use of learning objects, depending on the expertise of the teacher (expert vs. non-expert in e-Learning); (3) To confirm whether there are significant differences for the use of learning objects among students as a function of gender. Differences were found in the use of Moodle learning objects (resources and activities) for teachers and for students depending on the expertise of the teacher. Likewise, differences were found for the use of some learning objects as a function of gender and the degrees that the students were following. Increased technological training for both teachers and students is proposed, especially on Non-STEM qualifications, in order to mitigate the effects of the technological gap and its collateral relation with the gender gap and the digital divide.

Biodiesel can easily become the crucial solution for environmental problems. The high production rate of soybean oil has been the subject of several research works to transform it into biodiesel. Knowledge of the thermodynamic properties of soybean oil biodiesel (SOB) such as densities and coefficients of expansivity and compressibility play an important role in the understanding of the intermolecular interactions between the different molecules, which in turn have an impact on fuel quality. The difficulty in measuring the thermodynamic properties of biodiesel is because they are complex structures and high-molecular-weight components. The experimental density (136 points) for SOB, as a pseudopure component, at several temperatures (298.15–393.15 K) and pressures up to 140 MPa is reported. An Anton Paar vibrating tube densimeter, calibrated with an uncertainty of ±0.7 kg m–3, was used to perform these measurements. To determine the chemical fatty acid methyl ester composition, SOB was analyzed by CHNS analysis, 1H NMR, 13C NMR, and gas chromatography–mass spectrometry and, then, the density experimental data were correlated by the Tait and perturbed chain-statistical associating fluid theory (PC-SAFT) equations of state (EoS). The experimental data were compared with correlated data, resulting in absolute average deviation (AAD = 0.01%), maximum deviation (MD = 0.03%), average deviation (Bias = −9.88 × 10–7%), and standard deviation (σ = 1.18 × 10–4 g cm–3) for the empirical Tait equation. Concerning PC-SAFT EoS, the density was reasonably correlated with AAD = 0.063%. On the other hand, isothermal compressibility, κ T , and isobaric thermal expansivity, α p , were derived from the Tait equation. The same behavior is observed for κ T and α p , consistent with the expected one. The isobaric thermal expansivity, α p , presents a crossing point at nearly 35 MPa, in agreement with what had been observed by other authors.

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In this work, we reported the new experimental data of densities, speeds of sound, and refractive indices for four binary mixtures: {2-phenoxyethanol (2PhEE) + 1-propanol or 2-propanol or 1butanol or 2-butanol) over the entire composition range and at temperatures of (293.15, 303.15, 313.15 and 323.15) K and at pressure p = 0.1 MPa. From these experimental data, thermodynamics properties: excess molar volume, isentropic compressibility, deviation in isentropic compressibility and deviation in refractive indices were calculated. Excess molar volume, deviation in isentropic compressibility and deviation in refractive indices data have been correlated using the Redlich−Kister equation. From the obtained results, a discussion was carried out in terms of nature of intermolecular interactions and structure factors in these binary mixtures.