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In this work, binary mixtures of a non-ionic surfactant (Triton X-100) and water were studied with concentrations of 30%wt H2O, showing, lamellar mesophase at temperatures below 10oC. Different dicationic ionic liquids were used for doping these mesophases: 1,n-bis(3-methylimidazolium-1-yl)alkane, 1,n-bis(1-methylpyrrolidinium-1-yl)alkane and 1,n-bis(pyridinium-N-yl)alkane dibromide, where n = 6 and 8. Polarized Optical Microscopy and Small-Angle X-ray Scattering were used for identifying the mesophases and the influence of different dicationic ionic liquids on the lyotropic liquid crystals phase transitions. The addition of dicationic ionic liquids to the lyotropic liquid crystals samples led to changes in transition temperature and in mesophase structure itself (such as characteristic distances).

O óxido nítrico é uma molécula muito versátil, que pode ser encontrada tanto na atmosfera, como em diferentes organismos. Estudos revelaram suas variadas funções, como, por exemplo, ação antiplaquetária e vasodilatadora. Este trabalho visou caracterizar as propriedades ópticas não lineares destes S-nitrosotióis derivados de SNAP, aplicando a técnica conhecida como Z-Scan, que é amplamente utilizada, devido sua sensibilidade e precisão, e através de cálculos teóricos caracterizar as propriedades conformacionais destas moléculas, que possuem conformações mais estável sin 1 e sin 2, e são estabilizadas principalmente por ligações de hidrogênio intramoleculares, quando estão em meio com DMSO como solvente, seu momento de dipolo aumenta em comparação à fase gasosa. O composto com maior capacidade de liberar óxido nítrico foi o SNO 2-OMe e o de menor capacidade foi o SNO 2-Br. Infelizmente não foi possível traçar um paralelo com a conformação das moléculas e os resultados de Z-Scan. Os valores de difusividade térmica em geral são maiores para os S-nitrosotióis que para os tióis, já a condutividade térmica teve valores distintos para cada composto, independente da presença de NO e tipo de substituinte. Nitric oxide is a versatile molecule that can be found both in the atmosphere, as in many organisms. Studies have revealed its varied functions, for example, antiplatelet and vasodilatory actions. This study aimed to characterize the nonlinear optical properties of S-nitrosothiols derivatives of SNAP applying the technique known as Z-Scan, which is widely used due its sensitivity and accuracy, and through theoretical calculation to characterize the conformational properties of such molecules, that have more stable conformations syn 1 and syn 2, and are mainly stabilized by intramolecular hydrogen bonds. When DMSO is used as solvent, the molecules dipole moment increases as compared to the gas phase. The compound with greater ability to release nitric oxide was SNO 2-OMe and the one with lower capacity was SNO 2-Br. Unfortunately it was not possible to draw a parallel with the conformation of the molecules and the results of Z-Scan. The thermal diffusivity values are generally higher for the S-nitrosothiols in comparation with the thiols, thermal condutivity showed distinct values for each compound, regardless of the presence of NO and type of substituent. Dados abertos - Sucupira - Teses e dissertações (2013 a 2016)

In the future, teachers will guide students “in a learning process using Internet resources” (Le Monde, 2013). Since the digital era has a strong impact on the teaching profession, how to identify the actual results of introducing a “learner-centered” approach and digital technology in higher education, specifically schools of management ? Little has been written on this topic. Based on a cognitive-map methodology, this empirical study shows the effects of digitalization on activities, aptitudes and, above all, positions : teachers in higher education are becoming genuine tutors through their educational actions. It will be necessary to redesign the system for training, both initially and throughout careers, professors and researchers in educational methods and teaching skills., L’enseignant du futur devra guider les élèves « dans des apprentissages qu’ils mèneront eux-mêmes à partir de ressources Internet » (Le Monde, 2013). L’ère du numérique a un impact fort sur le métier d’enseignant ; nous avons donc cherché à identifier de façon plus précise les transformations de ce métier générées par l’introduction d’une pédagogie ‟learner-centered” et du numérique dans l’enseignement supérieur en gestion, un point encore peu étudié par la littérature. Notre étude empirique, basée sur la méthodologie de la carte cognitive, montre des impacts en termes d’activité, de compétences, mais surtout de posture : l’enseignant du supérieur devient un véritable tuteur par l’action formative qu’il conduit. Il faudra donc à l’avenir repenser les systèmes de formation initiale et continue des enseignants chercheurs sur le volet pédagogique de leur métier.