Search results for "ATAL"

La consciència del prestigi lingüístic entre els joves. Una aportació a l'estudi descriptiu de la inseguretat lingüística formal al País Valencià

2010

En aquest article presentem els resultats d'una investigació a gran escala sobre la Inseguretat Lingüística formal o laboviana (ILF). La mostra és representativa de l'univers estudiat -els joves valencians dels dos darrers cursos de l'ensenyament obligatori- i està formada pet 2190 estudiants entre 14 i 16 anys de 31 centres d'educació secundària de les localitats del País Valencià on es parla la llengua catalana. La ILF és un índex de la percepció que tenen els parlants de la distància que hi ha entre els seus usos lingüístics i les formes lingüístiques més prestigioses. En l'article es presenten els resultats de la ILF en l'ús de tretze variables fonètiques, morfològiques i lèxiques. S'hi…

Mercury beats Minerva? : essays on the accelerating impact of market logic permeating higher education

2015

Diastereomeric control of enantioselectivity: evidence for metal cluster catalysis

2014

Enantioselective hydrogenation of tiglic acid effected by diastereomers of the general formula [(μ-H)2Ru3(μ3-S)(CO)7(μ-P–P*)] (P–P* = chiral Walphos diphosphine ligand) strongly supports catalysis by intact Ru3 clusters. A catalytic mechanism involving Ru3 clusters has been established by DFT calculations. peerReviewed

Gas-Phase Hydrogenation of Propionitrile Catalyzed by LnCu2 (Ln = La, Ce, Pr, Nd)

2007

The hydrogenation of propionitrile over binary copper−lanthanide intermetallic compounds (LnCu2, Ln = La, Ce, Pr, Nd) was studied in the gas phase. The results show that the reaction main product is the primary amine, the n-propylamine. To our knowledge, it is the first time that such behavior is reported for copper catalysts.

"Le Ravissement de Lol V. Stein" et "La Princesse de Clèves" : une lecture intertextuelle des stéréotypes

2017

The subject matter of this article will be an intertextual analysis of the pivotal ball scenes in the novels Le Ravissement de Lol V. Stein by Marguerite Duras and La Princesse de Clèves by Madame de La Fayette. Despite the obvious differences in the poetics, creative visions, and styles of both writers, the reading of a 20th century literary work through the prism of the classic text exposes the stereotypes of love and a femme fatale also present in the novel by Duras. The ball from Le Ravissement de Lol V. Stein, which draws on the ball from La Princesse de Clèves, illustrates the complex nature of love as an unhappy, mysterious emotion. The 17th century literary work inspired Duras to im…

Mononuclear rearrangement of heterocycles in ionic liquids catalyzed by copper(II) salts

2008

Abstract The reactivity of E- and Z-phenylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole in the presence of CuCl2 and Cu(ClO4)2·6H2O has been studied in four imidazolium ionic liquids [bmim][X] (X=BF4−, PF6−, SbF6− and CF3SO3−). The reaction may follow different mechanistic patterns, depending on the nature of the ionic liquid anion, accounting for both qualitative and kinetic data. In the presence of CuCl2, two processes take place at the same time, i.e., the E⇆Z isomerization and the rearrangement of Z-isomer into the relevant 4-benzoylamino-2,5-diphenyl-1,2,3-triazole. In contrast, in the presence of Cu(ClO4)2·6H2O, the rearrangement occurs only in solution of [bmim][BF4] and [bmim][C…

Ionic liquid binary mixtures: Promising reaction media for carbohydrate conversion into 5-hydroxymethylfurfural

2014

Abstract The conversion of carbohydrates into 5-hydroxymethylfurfural (5-HMF) has been studied in binary mixtures of ionic liquids (ILs), using strongly acidic resin Amberlyst 15 as the catalyst. In particular, both mono- and disaccharides, such as fructose, glucose and sucrose have been investigated. Considering the favorable effect exerted by chloride-based ionic liquids in the dissolution of carbohydrates, we used binary mixtures of 1-butyl-3-methylimidazolium chloride ([bmim][Cl]) with [bmim + ] based ionic liquids differing in size, shape and coordination ability of the anion ([bmim][BF 4 ], [bmim][N(CF 3 SO 2 ) 2 ], [bmim][N(CN) 2 ], [bmim][SbF 6 ] and [bmim][CF 3 SO 3 ]). Carbohydrat…

Can the absence of solvation of neutral reagents by ionic liquids be responsible for the high reactivity in base-assisted intramolecular nucleophilic…

2005

[reaction: see text] The kinetics of the rearrangement of the Z-phenylhydrazone of 3-benzoyl-5-phenyl-1,2,4-oxadiazole (1a) into the relevant 4-benzoylamino-2,5-diphenyl-1,2,3-triazole (2a) induced by amines have been studied in two room-temperature ionic liquids (IL-1, [BMIM][BF4] and IL-2, [BMIM][PF6]). The data collected show that the reaction occurs faster in ionic liquids than in other conventional solvents previously studied (both polar or apolar, protic or aprotic). Presumably, this could depend on their peculiar ability to minimize the strong substrate-solvent, amine-solvent and amine-amine interactions occurring in conventional solvents.

Supported ionic liquids. New recyclable materials for L-proline-catalyzed aldol reaction

The effect of the cation p-surface area on the 3D organization and catalytic ability of imidazolium-based ionic liquids

2011

The dichotomic nature of ionic liquids (ILs, simple solvents or supramolecular fluids) induced us to carry out a structural investigation of some mono-and dicationic ionic liquids using 1D and 2D NMR, resonance light scattering, and UV/Vis spectroscopy. Ionic liquids with different cation π-surface areas were used, namely [bmim][NTf2], [Bzmim][NTf 2], [Bzbim][NTf2], [p-Xyl-(bim)2][NTf 2]2, and [m-Xyl-(bim)2][NTf2] 2 [bmim = 1-butyl-3-methylimidazolium, Bzmim = 1-benzyl-3- methylimidazolium, Bzbim = 1-benzyl-3-butylimidazolium, NTf2 = bis(trifluoromethansulfonyl)imide]. In order to verify to what extent the structural investigation, coupled with the determination of solvent parameters, could…