Importância da mediação na supervisão de estágios na formação de professores

Atualmente, podemos afirmar, com uma segurança que não possuíamos anteriormente, que a mediação de conflitos, enquanto nova ferramenta que veio juntarse às que já laboram em prol da paz e da harmonia social, se encontra culturalmente estabelecida no nosso país, nomeadamente no campo das relações familiares, laborais e até da pequena criminalidade. O interesse de realizar o presente trabalho de investigação surge da necessidade de compreender a importância da supervisão na formação de professores, do relacionamento do supervisor com o estagiário/futuro professor e todos os conflitos que daí advêm. Consideramos ser esta temática de grande atualidade uma vez que tem vindo, ultimamente, a suscitar grande interesse e preocupação junto dos professores, supervisores, estagiários e comunidade educativa em geral. Para a realização deste estudo, tivemos o cuidado de no âmbito da revisão de literatura desenvolver pesquisas no campo da supervisão, mediação e conflito

Experimental and Theoretical Study on Physical Properties of the Systems Dimethyl Carbonate and Diethyl Carbonate + Pentanol Isomers

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] In many industrial applications that involve solvents, the knowledge of both thermodynamics properties and transport properties play an important role in the design, sustainability, and optimization of processes in different fields of study. However, it is a fact that there is a lack of data and predictive models for the develop of future applications. Taking this into account, in this work we studied the physical properties of carbonates and pentanol isomers as well as their mixtures due to the versality of these solvents in many processes. We present measurements of densities (ρ) and excess molar volumes and enthalpies (VmE, HmE) at 298.15 K for the systems dimethyl or diethyl carbonate + pentanol isomers; and specifically for the systems with diethyl carbonate the surface tensions (σ ) and the surface tension deviations (δσ) at 298.15 K and the viscosities (η), dynamic viscosity deviations (Δη), refractive indexes (nD) and the changes in the refractive index (ΔnD) at 298.15 and 308.15 K. Different theoretical models were applied to obtained data for surface tensions and refractive indexes.Funding for open access charge: Universidade da Coruña/CISU

Physico-Chemical Characterization of Methanolic Mixtures of Cholinium Dihydrogen Phosphate-Based DES

[Abstract] The biocompatibility of three deep eutectic solvents based on cholinium dihydrogen phosphate for their use in lipase-catalyzed reactions was recently demonstrated, so the possible application as cosolvents with methanol in transesterification processes demands an exhaustive characterization of the physical properties. Thus, in this work binary and ternary deep eutectic solvents composed of the abovementioned salt as hydrogen bond acceptor and ethyleneglycol and/or glycerol as hydrogen bond donors were synthesized and mixed with methanol. The density, refractive index, electrical conductivity and dynamic viscosity were determined between 293.15 K and 323.15 K. The experimental data were correlated with different well-known equations and derived magnitudes like excess molar volumes, changes of refractive index on mixing and viscosity deviations were inferred in order to get an in-depth characterization of the studied mixtures with cholinium dihydrogen phosphate-based DES. The most intriguing data observed is the great peak measured for ionic conductivity at very high methanol concentration, which is difficult to explain even with the most recent theoretical models.The authors are grateful to Spanish Ministry of Science, Innovation and Universities for the financial support through the project RTI2018-094702-B-I00. The authors thank Xunta de Galicia and ERDF for funding through a postdoctoral grant (ED481D-2019/017) and Universidade de Vigo/CISUG for funding open access chargeXunta de Galicia; ED481D-2019/01

Experimental Device to Measure the Ionic Conductivity Anisotropy in Liquid Crystal Hydrogel Based In [EMIM] Alkyl Sulfate Ionic Liquids

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] We have built an experimental device with the aim to measure the expected electrical conductivity anisotropy in a liquid crystal, obtained from the gelation of the ionic liquid 1-ethyl-3-methyl imidazolium decyl sulfate, [EMIM][DSO4]. This ionic liquid has the particularity that it transits to a semi-solid gel state at room temperature when it contains water, naturally adsorbed from the environment until a balance is reached between the concentration of water in the IL and the atmospheric humidity grade. The quantity of water adsorbed to form the hydrogel at room temperature varies from about 5 to 30 wt%, each composition giving place to different smectic phases. In the gel state, the ionic liquid ions and the water molecules self-organize into micro-sized mesophases that resemble the structures of a liquid crystal. Our device is a closed 2D sample holder (with sides 150 times longer than its thickness), with a single narrow window open to the atmosphere, and four copper contacts on the sides. The dried ionic liquid is tempered at 40 °C to increase its fluidity when injected into the cavity, and then, it can only adsorb water through the narrow opening. Thus, water adsorption is unidirectional and slow, so the transition of the IL to the gel phase happens progressively. A metastable giant mesophase appears as an orientated macrodomain in the form of a striped pattern. In this state, we measure the electrical conductivity of the confined film in directions parallel and perpendicular to the observed strips, finding a difference of up to 26% between both values of the conductivity. If the sample freezes (below 10 °C) or it liquefies (above 50 °C) the meso structure is broken and the observed anisotropy destroyed. We can return the sample to gel state by varying the temperature, but the ordered macroscopic state is no longer recovered. This research must give clues to solve the charge transport mechanism quiz in ionic liquids and semi-solid coductors.This work was supported by Ministerio de Economia y Competitividad (MINECO) and FEDER Program through the projects MAT2017–89239-C2–1-P, MAT2017–89239-C2–2-P and RED2018–102679-T; Xunta de Galicia and FEDER (GRC 508 ED431C 2020/10). Funding for open access charge: Universidade da Coruña/CISUGXunta de Galicia; GRC 508 ED431C 2020/1

Influence of Small Quantities of Water on the Physical Properties of Alkylammonium Nitrate Ionic Liquids

This paper presents a comprehensive study of two alkylammonium nitrate ionic liquids. As part of this family of materials, mainly ethylammonium nitrate (EAN) and also propylammonium nitrate (PAN) have attracted a great deal of attention during the last decades due to their potential applications in many fields. Although there have been numerous publications focused on the measurement of their physical properties, a great dispersion can be observed in the results obtained for the same magnitude. One of the critical points to be taken into account in their physical characterization is their water content. Thus, the main objective of this work was to determine the degree of influence of the presence of small quantities of water in EAN and PAN on the measurement of density, viscosity, electrical conductivity, refractive index and surface tension. For this purpose, the first three properties were determined in samples of EAN and PAN with water contents below 30,000 ppm in a wide range of temperatures, between 5 and 95 °C, while the last two were obtained at 25 °C. As a result of this study, it has been concluded that the presence of water is critical in those physical properties that involve mass or charge transport processes, resulting in the finding that the absolute value of the average percentage change in both viscosity and electrical conductivity is above 40%. Meanwhile, refractive index (≤0.3%), density (≤0.5%) and surface tension (≤2%) present much less significant changesThis research was funded by the Spanish MINISTRY OF ECONOMY AND COMPETITIVENESS, grant numbers MAT2017-89239-C2-1-P and MAT2017-89239-C2-2-P. D. Ausín thanks the funding support of Fundación Segundo Gil Dávila. J.J. Parajó thanks the funding support of I2C postdoctoral program of Xunta de GaliciaS

Imidazolium Decyl Sulfate: A Very Promising Selfmade Ionic Hydrogel

This is the Accepted Manuscript version of the article. It has been through the peer review process at the Royal Society of Chemistry and has been accepted for publication in the journal "Materials Chemistry Frontiers".[Abstract] In this paper, we show, for the first time, the synthesis, structural characterization, phase diagram and physical properties of the ionic liquid, 1-ethyl-3-methyl imidazolium decyl sulfate [EMIm][DSO4]. At 25 °C it is either a crystalline solid or a liquid depending on the thermal history as its melting point is about 33 °C and its point of solidification is about 22 °C. The interest of this new IL lies in its ability to become a rigid hydrogel when mixed with water. As observed in many ILs, the as-prepared IL is hygroscopic and it adsorbs about 14 wt% of water at usual laboratory conditions and up to 27 wt% in a 100% saturated atmosphere. Due to the H-bonds between water and the amphiphilic [DSO4] anions, a lyotropic HIliquid crystalline phase is formed in the hydrated state, which can be observed in micrographs recorded using white polarized light. The moisture adsorption is a completely reversible process; thus, the rigid-gel sample loses all adsorbed water when it is left in a dry atmosphere for a few hours, transitioning to the liquid state. Phase diagrams of the temperature-water concentration is presented and compared with that of the parent compound [EMIm] octyl sulfate, [OSO4]. X-ray diffraction revels that below 15 °C the hydrated compound crystallizes into aP2/mmonoclinic structure. The structure of the new compound was confirmed by NMR, FTIR and mass spectroscopy (MS). In addition, the temperature behavior of ionic conductivity was experimentally measured and analyzed for the pure compound and for two samples hydrated with 10 wt% and 39 wt% of water. Viscosity and density were also measuredvs.temperature for the pure sample. The as-prepared IL shows great potential for numerous practical applications.This work was financed by MINECO from the Spanish Government (Grants No. MAT2014-57943-C3-1-P, MAT2014-57943-C3-2-P, MAT2014-57943-C3-3-P and DPI2012-38841-C02-02), by the European Union (COST Action CM 1206) and by the Galician Network on Ionic Liquids, REGALIs (CN 2014/015). Research projects have been co-financed by the European Regional Development Fund (FEDER

Strange Behaviour of Transport Properties in Novel Metal Thiocyanate Based Ionic Liquids

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUGThe following are the Supplementary data to this article: https://ars.els-cdn.com/content/image/1-s2.0-S0167732221018882-mmc1.docx[Abstract] In a previous paper some of us presented the structure and some properties of a new family of ionic liquids, ILs, with a common cation, 1-butyl-3-methyl imidazolium (the popular [C4C1Im]⁺ or [BMIM]⁺) and a variety of anions based in thiocyanate (SCN)¯: one reference sample and ten with anionic metal complexes of different valences: Al¹¹¹, Mn¹¹, Fe¹¹, Cr¹¹¹, Ni¹¹, Hg¹¹, Zn¹¹, Co¹¹ and Cu¹, resulting, respectively, [BMIM](SCN), [BMIM]₃ Al(SCN)₆, [BMIM]₄ Mn(SCN)₆, [BMIM]₃ Fe(SCN)₆, [BMIM]₃ Cr(SCN)₆, [BMIM]₄ Ni(SCN)₆, [BMIM]₂ Hg(SCN)₄, [BMIM]₂ Zn(SCN)₄, [BMIM]₂ Co(SCN)₄ and [BMIM]₃ Cu(SCN)₄. In this paper we show experimental measurements of electrical conductivity of these ILs in a broad temperature range (about 90 K). Viscosity has been measured for six compounds in a wide temperature range. In addition, the diffusion coefficient for both ions forming the IL has been measured for some of the samples using NMR-Dosy technique. In spite of being very similar compounds from a chemical point of view, they present very different transport property values. Thus, viscosity varies more than two orders of magnitude among those metal thiocyanate ILs, being the highest for the compound with Al and the lowest for that with Hg. Moreover, differences between ionic conductivity and diffusion coefficient values extend more than one order of magnitude among the thiocyanate ILs. These three properties will be related in pairs, thus through Walden’s rule we compare molar conductivity and fluidity, while using Kohlrausch’s law and Nerst-Einstein equation molar conductivity and diffusion coefficient are related. Also, diffusion coefficient and fluidity (the inverse of viscosity) are compared by means of Stokes-Einstein relationship. In addition, we calculate the Laity interionic friction coefficients for both anions of the IL with Hg. Finally, a theoretical model is suggested to explain all the experimental evidences reported.We acknowledge the financial support of Ministerio de Economía y Competitividad MINECO) (MAT2017-86109-P and MAT2017-89239-C2-(1.2)-P); and Xunta de Galicia (AGRU 015/11. GRC ED431C 2016/001 and ED431D 2017/06). All these research projects were partially supported by FEDER. Also, D.A. acknowledges Gil Dávila Foundation for his postgraduate grant. Funding for open access charge: Universidade da Coruña/CISUG.Xunta de Galicia; ED431C 2016/001Xunta de Galicia; ED431D 2017/06https://ars.els-cdn.com/content/image/1-s2.0-S0167732221018882-mmc1.doc

Synthesis, microstructure and volumetry of novel metal thiocyanate ionic liquids with [BMIM] cation

We present a new family of ionic liquids (ILs) with a common cation, 1-butyl-3-methyl imidazolium, the popular [BMIM]+ (also written C4C1Im+) and a variety of anionic complexes (also called adducts) based in thiocyanate (SCN)?: one blank compound, BMIM(SCN), and ten doped with metals having different oxidation states: Al+3, Mn+2, Fe+3, Cr+3, Ni+2, Hg+2, Zn+2, Co+2, Cd+2 and Cu+, forming, respectively, [BMIM]3[Al(SCN)6], [BMIM]4 Mn(SCN)6, [BMIM]3 Fe(SCN)6, [BMIM]3 Cr(SCN)6, [BMIM]4 Ni(SCN)6, [BMIM]2 Hg(SCN)4, [BMIM]2 Zn(SCN)4, [BMIM]2 Co(SCN)4, [BMIM]2 Cd(SCN)4 and [BMIM]3 Cu(SCN)4. All of them were synthesized by us, except the blank IL and the Co thiocyanate, which are commercial. Obtained products have been characterized by NMR, and also by electrospray ionization, MS-ES, which allows the determination of the new ILs purities. Then, compounds have been analyzed using FT-IR and Raman spectroscopy. In addition, magnetic susceptibility and refractive index measurements were performed in some of the compounds studied, as well as thermal characterization using DSC and TGA. Finally, experimental measurements of density on all those ILs have been performed, and for some of the samples in a broad temperature range (about 100 K). In spite of being very similar compounds from the chemical point of view, they present quite different physical properties, including optical, thermal and magnetic ones? Also, they show different oxidation states (one with +1, six with +2 and other three with +3). We guess that this family of ILs will have interesting applications, mainly for photonic devices

On the physical properties of mixtures of nitrate salts and protic ionic liquids

We report a systematic study of the effect of salt concentration and its cation valence on several equilibrium and transport properties of mixtures of the model protic ionic liquid ethylammonium nitrate with monovalent (LiNO3), divalent (Mg(NO3)2 and Ca(NO3)2), and trivalent (Al(NO3)3) salts. These properties, determined by appropriate experimental techniques, include density, sound velocity, refractive index, surface tension, conductivity and viscosity. Single-particle dynamics and radial distribution functions were also analyzed by means of molecular dynamics simulations. The temperature dependence of the conductivity was studied in the Vogel-Fulcher-Tammann framework, and we obtained effective activation energies, fragility indexes, and Vogel temperatures. In addition, we performed a high-temperature Arrhenius analysis and we calculated the activation energies of both conductivity and viscosity. Finally, the exponents of the fractional Walden rule for the different mixtures were obtained and the ionicities and fragilities of the systems were analyzed, proving that all the mixtures are subionic and fragile. The distortion of the network of hydrogen bonds characteristic of protic ionic liquids and the formation of long-lived anionic aggregates composed of the cations of the added salt and the nitrate anions in their first solvation shell were found to have a deep impact on the analyzed properties. The role of the surface charge density of the salt cations on the structure and transport properties of the solutions is detailedly analyzed and related to solvation of salt species in the polar nanoregions of the ionic liquid (nanostructured solvation)The financial support of the Spanish Ministry of Economy and Competitiveness (Projects MAT2017-89239-C2-1-P and MAT2017-89239- C2-2-P) is gratefully acknowledged. Moreover, this work was funded by the Xunta de Galicia (ED431D 2017/06, ED431E 2018/08, GRC ED431C 2016/001 and GRC ED431C 2020/10). All these research projects were partially supported by FEDER. P. V. thanks the Spanish Ministry of Science, Innovation and Universities for his FPI grant (PRE2018-084212). T.M.-M. thanks the Spanish Ministry of Science, Innovation and Universities for her Juan de la Cierva grant (IJC2018-036774-I).J. J. Parajó thanks the funding support of I2C postdoctoral program of Xunta de Galicia. Y. A. thanks the funding support from postdoctoral Program of Xunta de Galicia (ED481B-2021-027)S