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Póster utilizado en la IV Jornada de investigación predoctoral en Derecho organizada por la Universidad de Zaragoza, panel "Instituciones políticas y administrativas", 26 de mayo de 2022.

Texto completo. Acesso restrito. p. 141-150 Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-06-25T18:12:55Z No. of bitstreams: 1 252525mm.pdf: 886657 bytes, checksum: b7fabc55a8045a149328cf7dcb314890 (MD5) Approved for entry into archive by Rodrigo Meirelles (rodrigomei@ufba.br) on 2013-11-19T20:58:16Z (GMT) No. of bitstreams: 1 252525mm.pdf: 886657 bytes, checksum: b7fabc55a8045a149328cf7dcb314890 (MD5) Made available in DSpace on 2013-11-19T20:58:16Z (GMT). No. of bitstreams: 1 252525mm.pdf: 886657 bytes, checksum: b7fabc55a8045a149328cf7dcb314890 (MD5) Previous issue date: 2013 Ionic liquids (ILs) have evolved as a new type of non-aqueous solvents for biocatalysis, mainly due to their unique and tunable physical properties. A number of recent review papers have described a variety of enzymatic reactions conducted in IL solutions, on the other hand, to improve the enzyme’s activity and stability in ILs; major methods being explored include the enzyme immobilization (on solid support, sol–gel, etc.), protic ionic liquids used as an additive process. The immobilization of the lipase from Burkholderia cepacia by the sol–gel technique using protic ionic liquids (PIL) as additives to protect against inactivation of the lipase due to release of alcohol and shrinkage of the gel during the sol–gel process was investigated in this study. The influence of various factors such as the length of the alkyl chain of protic ionic liquids (monoethanolamine-based) and a concentration range between 0.5 and 3.0% (w/v) were evaluated. The resulting hydrophobic matrices and immobilized lipases were characterised with regard to specific surface area, adsorption–desorption isotherms, pore volume (Vp) and size (dp) according to nitrogen adsorption and scanning electron microscopy (SEM), physico-chemical properties (thermogravimetric – TG, differential scanning calorimetry – DSC and Fourier transform infrared spectroscopy – FTIR) and the potential for ethyl ester and emulsifier production. The total activity yields (Ya) for matrices of immobilized lipase employing protic ionic liquids as additives always resulted in higher values compared with the sample absent the protic ionic liquids, which represents 35-fold increase in recovery of enzymatic activity using the more hydrophobic protic ionic liquids. Compared with arrays of the immobilized biocatalyst without additive, in general, the immobilized biocatalyst in the presence of protic ionic liquids showed increased values of surface area (143–245 m2 g−1) and pore size (19–38 A˚ ). Immobilization with protic ionic liquids also favoured reduced mass loss according to TG curves (always less than 42.9%) when compared to the immobilized matrix without protic ionic liquids (45.1%), except for the sample containing 3.0% protic ionic liquids (46.5%), verified by thermogravimetric analysis. Ionic liquids containing a more hydrophobic alkyl group in the cationic moiety were beneficial for recovery of the activity of the immobilized lipase. The physico-chemical characterization confirmed the presence of the enzyme and its immobilized derivatives obtained in this study by identifying the presence of amino groups, and profiling enthalpy changes of mass loss. Salvador

Texto completo: acesso restrito. p. 2802–2809 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-02-18T14:15:20Z No. of bitstreams: 1 Miguel Iglesias.pdf: 117917 bytes, checksum: 0102cfad36922c2bd2960d25c82a7613 (MD5) Approved for entry into archive by LIVIA FREITAS (livia.freitas@ufba.br) on 2014-07-03T16:38:59Z (GMT) No. of bitstreams: 1 Miguel Iglesias.pdf: 117917 bytes, checksum: 0102cfad36922c2bd2960d25c82a7613 (MD5) Made available in DSpace on 2014-07-03T16:38:59Z (GMT). No. of bitstreams: 1 Miguel Iglesias.pdf: 117917 bytes, checksum: 0102cfad36922c2bd2960d25c82a7613 (MD5) Previous issue date: 2011 A study of the ecotoxicity of different short aliphatic protic ionic liquids (PILs) on terrestrial organisms was conducted. Tests performed within the present study include those assessing the effects of PILs on soil microbial functions (carbon and nitrogen mineralization) and terrestrial plants. The results show that the nominal lowest-observed-adverse-effect concentration (LOAEC) values were 5,000 mg/kg (dry soil) for the plant test in two species (Lolium perenne, Allium cepa), 1,000 mg/kg (dry soil) for the plant test in one species (Raphanus sativus), and 10,000 mg/kg (dry soil) for carbon and nitrogen microbial transformation tests (all concentrations are nominal). Most of the median effective concentration values (EC50) were above 1,000 mg/kg (dry soil). Based on the obtained results, these compounds can be described as nontoxic for soil microbiota and the analyzed plants, and potentially biodegradable in soils, as can be deduced from the respirometric experiment. The toxicity rises with the increase of complexity of the PILs molecule (branch and length of aliphatic chain) among the three PILs analyzed. Environ. Toxicol. Chem. 2011;30:2802–2809. © 2011 SETAC

Acesso restrito: Texto completo. p. 42-50. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-04-11T18:46:55Z No. of bitstreams: 1 __ac.els-cdn.com_S037838...0dfe6e4912bc01a3cd535479e22a9.pdf: 560799 bytes, checksum: c4346d52b99a775cb6f5fc1ced5912e9 (MD5) Made available in DSpace on 2012-04-11T18:46:55Z (GMT). No. of bitstreams: 1 __ac.els-cdn.com_S037838...0dfe6e4912bc01a3cd535479e22a9.pdf: 560799 bytes, checksum: c4346d52b99a775cb6f5fc1ced5912e9 (MD5) Previous issue date: 2010-12 This work reports the synthesis of 2-hydroxy ethylammonium oleate and bis(2-hydroxy ethyl)ammonium oleate ionic liquids, which have a long aliphatic chain as well as the study of some of their physical properties, in particular the effect of temperature on their density, speed of sound, viscosity, and refractive index. 1H and 13C NMR spectra were used to characterize the chemical structure of the species in concordance with FT-IR spectra. DOSY NMR spectra were used to determine the self-diffusion coefficients of 2-hydroxy ethylammonium oleate ionic liquid, which were consistent with the formation of a lamellar or micellar liquid crystal phase; due the similar structure, a similar aggregation in the bis(2-hydroxy ethyl)ammonium oleate ionic liquid it is expected.

Trabalho completo: acesso restrito, p. 625–632 Submitted by Bruna Lessa (lessbruna@gmail.com) on 2012-05-30T21:10:32Z No. of bitstreams: 1 (45)je900550v.pdf: 269197 bytes, checksum: a1a474765bbf865b7c96747b970f78c3 (MD5) Made available in DSpace on 2012-05-30T21:10:32Z (GMT). No. of bitstreams: 1 (45)je900550v.pdf: 269197 bytes, checksum: a1a474765bbf865b7c96747b970f78c3 (MD5) Previous issue date: 2010 This report describes the synthesis of ionic liquids that incorporate the N-methyl-2-hydroxyethylammonium cation with various carboxylic acid anions and the study of some of their physical properties, including self-diffusion coefficients, density, speed of sound, viscosity, and refractive index. 1H and 13C NMR spectra were used to characterize the chemical structure of the species in concordance with FT-IR spectra. DOSY NMR spectra was used to determine the self-diffusion coefficients of the components, which were consistent with the formation of a lamellar or micellar liquid-crystal phase in samples containing an alkyl chain in the anion species. Thermoacoustic parameters showed that anion alkyl chain has an influence on the molecular packing of these ionic liquids. In addition, the effect of temperature on the properties seems to be related to the size and the type of aliphatic chain of the ionic liquid.

Acesso restrito: Texto completo. p. 802-808 Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-04-19T14:00:44Z No. of bitstreams: 1 __ac.els-cdn.com_S138589...e4af765fd2b4a9735a9009f5b2aa8.pdf: 323575 bytes, checksum: 727975a6c9fac907ab858015848fd098 (MD5) Made available in DSpace on 2012-04-19T14:00:44Z (GMT). No. of bitstreams: 1 __ac.els-cdn.com_S138589...e4af765fd2b4a9735a9009f5b2aa8.pdf: 323575 bytes, checksum: 727975a6c9fac907ab858015848fd098 (MD5) Previous issue date: 2010 A serie of substituted amines based ionic liquids was prepared using an aliphatic linear carboxylic acid (pentanoic acid). The ionic liquids synthesised are 2-hydroxy ethylammonium pentanoate (2-HEAPE), 2-hydroxy diethylammonium pentanoate (2-HDEAPE) and 2-hydroxy triethylammonium pentanoate (2-HTEAPE). FT-IR spectra establishes their ionic salt structure. The influence of structural variations on their thermodynamic properties (density, ultrasonic velocity, ionic conductivity, refractive index, viscosity and surface tension) was investigated, as a function of temperature in the range 278.15–338.15 K. In the compounds studied here, the anion has strong effect on the properties if compared with previous studies of the authors, when shorter chains were used. It was found that the elongation of the alkyl chain causes the pronounced depression of fluidity and ionic conductivity. The observed temperature trend of the studied properties points out the special packing of these ionic liquids, as well as, the strong influence of the steric hindrance among linear aliphatic residues. We also describe the catalytic activity of these type of ionic liquids for a representative serie of aldol condensation processes. Conversions higher than 98% and selectivities higher than 85% were obtained. Moreover the catalysts are easily separated from reaction mixture and re-used, obtaining good conversions for at least three consecutive cycles. As a conclusion, it was found that simple structural modifications into anion length and degree of substitution provide a mechanism to manipulate the catalytic potency of these ionic liquids, as well as, tailor physico-chemical properties for potential end-use applications.

Texto completo: acesso restrito. p. 384–395 Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2014-03-11T14:46:41Z No. of bitstreams: 1 1-s2.0-S0045653506011817-main.pdf: 347411 bytes, checksum: 6beaa8847c03505009736efafa41d1d9 (MD5) Approved for entry into archive by LIVIA FREITAS (livia.freitas@ufba.br) on 2014-07-08T14:49:58Z (GMT) No. of bitstreams: 1 1-s2.0-S0045653506011817-main.pdf: 347411 bytes, checksum: 6beaa8847c03505009736efafa41d1d9 (MD5) Made available in DSpace on 2014-07-08T14:49:58Z (GMT). No. of bitstreams: 1 1-s2.0-S0045653506011817-main.pdf: 347411 bytes, checksum: 6beaa8847c03505009736efafa41d1d9 (MD5) Previous issue date: 2007 The potential environmental impact of aromatic and halogenated chemicals from the petrochemical and steel industry is of growning concern. The present paper deals with the modelling and experimental determination of density and speed of sound at the range 278.15–323.15 of six aromatic and halogenated compounds (Benzene, Toluene, Ethylbenzene, Fluorobenzene, 2-Fluorotoluene and Chlorobenzene). Fitting equations were applied to the data in order to correlate for later computer based design. The estimation of the studied properties was made by the application of different theoretical procedures. The Mchaweh–Nasrifar–Moshfeghian model (MNM), an equation of state based on the generalized van der Waals theory which combines the Staverman–Guggenheim combinatorial term of lattice statistics with an attractive lattice gas expression and the Free Length Theory showed a good response at the studied conditions.

La radiografía posteroanterior de tórax (Rx) es empleada rutinariamente por el clínico como herramienta para el estudio del paciente con hipertensión arterial sistémica (HAS) a fin de evaluar las dimensiones del corazón. Sin embargo, la sensibilidad más alta reportada para la valoración del crecimiento cardíaco empleando este método es del 77.3%, frente al ecocardiograma transtorácico (ETT) que alcanza entre el 90 y 100%. La finalidad de este estudio fue determinar en nuestra población de pacientes con HAS, la correlación entre la Rx y el ETT en la valoración de cardiomegalia. Pacientes y métodos: Se realizó ETT a 72 pacientes con HAS y cardiomegalia radiológica graduada con base en los valores del índice cardiotorácico (ICT). Se determinaron los coeficientes de correlación de Pearson y Spearman. La significancia se fijó en < 0.05. Resultados: Cuarenta y un (56.9%) pacientes fueron mujeres y 31 (43.1%) hombres. La edad fue de 62.4 ± 10 años (43-83 años). Fue observada hipertrofia concéntrica ventricular izquierda (HCVI) en 56 (77.8%). En 13 (18.0%) pacientes el diámetro diastólico final del ventrículo izquierdo (DDFVI) fue superior al valor normal. El coeficiente de correlación de Pearson entre el grosor septal interventricular en diastole (GSD) y el ICT fue de 0.285 (p < 0.05). Mientras que entre el DDFVI y la cardiomegalia radiológica fue de 0.203 (p = NS). Conclusiones: En pacientes con HAS la cardiomegalia radiológica guarda correlación con hipertrofia ventricular izquierda pero no con dilatación ventricular.