Mobile devices' popularity, particularly tablets and smartphones, has increased over the last years as a result of their versatility and multifunctionality. That consequently led to a wide daily use by everyone and especially among young people. Since 2010 the sales market for mobile devices has not stopped growing. This is justified by the fact that these devices present many advantages, namely usability, portability, versatility, adaptability and an ability to customize individual experiences. In the context of the teaching-learning process, mobile devices allow overcoming the temporal and physical boundaries of the classroom, since information is omnipresent and no longer limited to a specific time and place for learning, thus promoting the mLearning. In this way it is important to analyze the use of mLearning, particularly the acceptance rate and uses of mobile technologies devices in higher education Portuguese institutions. In order to answering this issue, this paper analyzes the evolution and trends in the use of mobile technologies in higher education institutions in Portugal (North region) between
Three novel water-soluble 2D copper(II) coordination polymers-[{Cu2(μ2-dmea)2(H2O)}2(μ4-pma)]n·4nH2O (1), [{Cu2(μ2-Hedea)2}2(μ4-pma)]n·4nH2O (2), and [{Cu(bea)(Hbea)}4(μ4-pma)]n·2nH2O (3)-were generated by an aqueous medium self-assembly method from copper(II) nitrate, pyromellitic acid (H4pma), and different aminoalcohols [N,N-dimethylethanolamine (Hdmea), N-ethyldiethanolamine (H2edea), and N-benzylethanolamine (Hbea)]. Compounds 2 and 3 represent the first coordination polymers derived from H2edea and Hbea. All the products were characterized by infrared (IR), electron paramagnetic resonance (EPR), and ultraviolet-visible light (UV-vis) spectroscopy, electrospray ionization-mass spectroscopy (ESI-MS(±)), thermogravimetric and elemental analysis, and single-crystal X-ray diffraction (XRD), which revealed that their two-dimensional (2D) metal-organic networks are composed of distinct dicopper(II) or monocopper(II) aminoalcoholate units and μ4-pyromellitate spacers. From the topological viewpoint, the underlying 2D nets of 1-3 can be classified as uninodal 4-connected layers with the sql topology. The structures of 1 and 2 are further extended by multiple intermolecular hydrogen bonds, resulting in three-dimensional (3D) hydrogen-bonded networks with rare or unique topologies. The obtained compounds also act as highly efficient precatalysts for the mild homogeneous oxidation, by aqueous H2O2 in acidic MeCN/H2O medium, of various cycloalkanes to the corresponding alcohols and ketones. Overall product yields up to 45% (based on cycloalkane) were attained and the effects of various reaction parameters were investigated, including the type of precatalyst and acid promoter, influence of water, and substrate scope. Although water usually strongly inhibits the alkane oxidations, a very pronounced promoting behavior of H2O was detected when using the precatalyst 1, resulting in a 15-fold growth of an initial reaction rate in the cyclohexane oxidation on increasing the amount of H2O from ∼4 M to 17 M in the reaction mixture, followed by a 2-fold product yield growth.
The reactivity of the new gallium(III) complex of 3-vinyl-5,10,15-tris(pentafluorophenyl)corrole 4, as a diene in Diels-Alder reactions was studied using 1,4-benzoquinone and 1,4-naphthoquinone as dienophiles. In these reactions only the dehydrogenated adducts 5 and 6 were isolated. All the new corrole derivatives 4-6 were fully characterized by elemental analysis, 1 H-NMR, 13 C-NMR, 19 F-NMR, MALDI-TOF-MS, UV-Vis absorption and emission spectroscopy. The sensing ability of compounds 4-6 and of their precursors 1-3 was studied in solution towards the spherical halide ions F À , Cl À , Br À , I À , the linear anion CN À and the bulky anions CH 3 COO À and H 2 PO 4 À . This study was also realized in gas-phase with the anions F À and CN À . A red-shift in the absorption spectra and an enhancement in the emission intensity were observed, with compounds 1, 3 and 5 being strongly sensitive to fluoride. The highest association constant was obtained for 1 with F À , being able to quantify 0.69 ppm of this anion. On the other hand, compounds 1 and 2 present a high sensitivity towards cyanide anions, producing a red-shift in the absorption and emission spectra and an increase in the emission intensity, being able to quantify a minimal amount of 1.43 ppm. Moreover, compounds 1 and 5 were used to prepare two lowcost solid polymers, based on polymethylmethacrylate (PMMA) and polyacrylamide, the last one being very promising since it is able to detect ca. 70.0 ppb of CN À in water. Compounds 2a and 5 were also tested in the presence of 4,4 0 -bipyridine, caffeine and nicotine and compound 2a proved to be very sensitive to 4,4 0 -bipyridine, while compound 5 was really effective for detecting caffeine and nicotine.
New compounds of the general formulas [M(Ar-BIAN)(2)]BF(4) and [M(Ar-BIAN)(NCMe)(2)]BF(4), where M = Cu(I) or Ag(I) and Ar-BIAN = bis(aryl)acenaphthenequinonediimine, were synthesized by the direct reaction of [Cu(NCMe)(4)]BF(4) or [Ag(NCMe)(4)]BF(4) with the corresponding Ar-BIAN ligand in dried CH(2)Cl(2). The synthesized compounds are [M(o,o',p-Me(3)C(6)H(2)-BIAN)(2)]BF(4) where M = Cu(I) (1) and Ag(I) (2), [M(o,o'-iPr(2)C(6)H(3)-BIAN)(NCMe)(2)]BF(4) where M = Cu(I) (3) and Ag(I) (4), and [Ag(o,o'-iPr(2)C(6)H(3)-BIAN)(2)]BF(4) (5). The crystal structures of compounds 1-3 and 5 were solved by single-crystal X-ray diffraction. In all cases copper(I) or silver(I) are in a distorted tetrahedron that is constructed from the four nitrogen atoms of the two α-diimine ligands or, in 3, from one α-diimine ligand and two acetonitrile molecules. All compounds were characterized by elemental analyses, matrix-assisted laser desorption-ionization time-of-flight mass spectrometry, and IR, UV-vis, and (1)H NMR spectroscopy. The analysis of the molecular geometry and the energetic changes for the formation reactions of the complexes, in a CH(2)Cl(2) solution, were evaluated by density functional theory calculations and compared with the experimental results.
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