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Crystal structure of 5′′-benzylidene-1′-methyl-4′-phenyltrispiro[acenaphthylene-1,2′-pyrrolidine-3′,1′′-cyclohexane-3′′,2′′′-[1,3]dioxane]-2,6′′-dione
2016
In the title trispiro compound, both the methyl-substituted pyrrolidine and dioxalane rings adopt a twist conformation. The cyclopentanone ring of the acenapthylen-1-one system adopts flattened envelope conformation, and the cyclohexanone attached to the dioxalane ring adopts boat conformation. In the crystal, centrosymmetrically related molecules are linked into dimers forming rings of (10) graph-set motif, which are further connected into chains parallel to the b axis by C—H⋯O contacts forming rings of (8) graph-set motif.
Colaboración y desarrollo profesional del profesorado. Regulaciones presentes en la estructura del puesto de trabajo.
2004
La finalidad de esta tesis doctoral es comprender las repercusiones educativas, personales y sociales que se derivan del hecho de que los profesores trabajen en colaboración, especialmente en lo que se refiere a su desarrollo profesional. A partir de la comprensión de estos hechos se propone también contribuir a la mejora de la práctica docente. La investigación parte de un marco conceptual que puede resumirse en los puntos siguientes:· La colaboración entre profesores es considerada beneficiosa por la sociedad a pesar de oponerse a los valores neoliberales presentes en ésta.· Aunque existe un fuerte consenso en torno a la necesidad de colaborar, en el trabajo de los profesores predomina el…
An easy access to fused chromanones via rhodium catalyzed oxidative coupling of salicylaldehydes with heterobicyclic olefins
2016
Abstract Herein we describe a detailed study on the rhodium catalyzed oxidative coupling of salicylaldehydes with heterobicyclic olefins such as diazabicyclic olefins and urea-derived bicyclic olefins. The developed method provides an ideal route to fused chromanone systems in a single synthetic step. Moreover, the scope of this methodology was extended to different oxa/aza-bridged bicyclic urea derivatives.
An easy access to fused chromanones via rhodium catalyzed oxidative coupling of salicylaldehydes with heterobicyclic olefins
2016
Herein we describe a detailed study on the rhodium catalyzed oxidative coupling of salicylaldehydes with heterobicyclic olefins such as diazabicyclic olefins and urea-derived bicyclic olefins. The developed method provides an ideal route to fused chromanone systems in a single synthetic step. Moreover, the scope of this methodology was extended to different oxa/aza-bridged bicyclic urea derivatives. peerReviewed
Preparation and physico-chemical study of inclusion complexes between idebenone and modified beta-cyclodextrins
1996
The inclusion properties of modifiedβ-cyclodextrins (trimethyl-β-cyclodextrin, dimethyl-β-cyclodextrin and hydroxypropyl-β-cyclodextrin) towards idebenone were compared with naturalβ-cyclodextrin. The inclusion complexes were prepared by different methods (coprecipitation, kneading, and freeze-drying) and characterized by differential scanning calorimetry, X-ray diffractometry, UV, CD and NMR spectroscopy. The results obtained by CD and NMR spectroscopy indicate a different orientation of idebenone in dimethyl-β-cyclodextrin with respect to other cyclodextrins. Stability constants of the complexes were determined in water at various temperatures and consequently thermodynamic parameters wer…
Inhimillisen ja ei-inhimillisen suhde Eija Lappalaisen ja Anne Leinosen trilogiassa Routasisarukset
2014
Pro gradu -työssäni tutkin Eija Lappalaisen ja Anne Leinosen kirjoittaman dystooppisen Routasisarukset-trilogian teoksia Routasisarukset (2011), Hiekkasotilaat (2012) ja Konejumalat (2013). Tutkimuksessani keskityn kuvaamaan ja analysoimaan trilogian esityksiä inhimillisestä ja ei-inhimillisestä sekä niiden välistä suhdetta. Tutkielmani teoreettisena taustana ovat ekokritiikin ja kriittisen posthumanismin teoretisoinnit, joiden yhteisiä piirteitä pyrin tutkimuksessani kartoittamaan ja soveltamaan. Lähiluvun avulla analysoin trilogian esityksiä ihmisyydestä, eri lajien välisistä suhteista sekä lopulta laajemmin sitä, millaisia merkityksiä inhimillinen ja ei-inhimillinen näiden kuvausten kaut…
Dietary exposure to mycotoxins through the consumption of commercial bread loaf in Valencia, Spain
2017
Abstract In this study, 80 commercial samples of bread loaves were purchased from different supermarkets located in Valencia (Spain). These samples were investigated for the presence of legislated and non-legislated mycotoxins. Results showed that samples were contaminated with Aflatoxins (AFs), Zearalenone (ZEA) and Enniatins (ENs) with a frequency of 20, 96, and 65% respectively. Aflatoxin B1 (AFB1), Aflatoxin B2 (AFB2) and Aflatoxin G1 (AFG1) were detected with concentrations ranged from 0.5 to 7.1 μg/kg. The samples contaminated with AFB1 showed values exceeding the maximum limit allowed in the EU. The sum of AFs also exceeded the maximum limit allowed in 6 samples. ENs contamination da…
2016
The photochemistry of benzophenone, a paradigmatic organic molecule for photosensitization, was investigated by means of surface-hopping ab initio molecular dynamics. Different mechanisms were found to be relevant within the first 600 fs after excitation; the long-debated direct (S1 → T1) and indirect (S1 → T2 → T1) mechanisms for population of the low-lying triplet state are both possible, with the latter being prevalent. Moreover, we established the existence of a kinetic equilibrium between the two triplet states, never observed before. This fact implies that a significant fraction of the overall population resides in T2, eventually allowing one to revisit the usual spectroscopic assignm…
Understanding the stereo- and regioselectivities of the polar Diels-Alder reactions between 2-acetyl-1,4-benzoquinone and methyl substituted 1,3-buta…
2009
The polar Diels–Alder (DA) reactions of 2-acetyl-1,4-benzoquinone (acBQ) with methyl substituted 1,3-butadienes have been studied using DFT methods at the B3LYP/6-31G(d) level of theory. These reactions are characterized by a nucleophilic attack of the unsubstituted ends of the 1,3-dienes to the β conjugated position of the acBQ followed by ring-closure. The reactions present a total regioselectivity and large endo selectivity. The analysis based on the global electrophilicity of the reagents at the ground state, and the natural bond orbital (NBO) population analysis at the transition states correctly explain the polar nature of these cycloadditions. The large electrophilic character of acB…
Evaluation of Mycotoxin Residues on Ready-to-Eat Food by Chromatographic Methods Coupled to Mass Spectrometry in Tandem
2018
Simultaneous determination of twenty-seven mycotoxins in ready-to-eat food samples using &ldquo