Mostrando ítems 81-100 de 144

    Development of new solvent-free microextraction techniques for the analysis of volatile organic compounds: application to the use of breath analysis as a toxicological tool for explosure analysis 

    Alonso Roura, Mònica (Fecha de defensa: 2012-12-14)

    Hippocrates predicted many years ago that breath could tell something related with our health. On his treaties, he indicated that when the body starts moving after sleeping, and breathe with more frequency, something hot ...

    Hollow fiber liquid-phase microextraction in the determination of pharmaceuticals and personal care products 

    Sagristà i Puig, Ester (Fecha de defensa: 2012-11-23)

    Extensive amounts of pharmaceuticals and personal care products (organic emerging pollutants) are introduced into the environment mainly through wastewater treatment plants discharges either effluent wastewater reaching ...

    Desenvolupament, implementació i aplicació de nova metodologia pel càlcul de la contribució vibracional a les propietats elèctriques: contribucions de relaxació nuclear i curvatura 

    Luis Luis, Josep Maria (Fecha de defensa: 1999-06-28)

    The vibrational contribution to nonlinear optics (NLO) properties is the mean goal of study of this Thesis. The vibrational contribution can be split in the nuclear relaxation contribution and the curvature contribution. ...

    Activació d'O2, HOOH i t-BuOOH amb complexos de Cu i Fe amb lligands N-heterocíclics aromàtics i macrocíclics per l'oxidació de substrats orgànics i inorgànics en condicions suaus 

    Costas Salgueiro, Miquel (Fecha de defensa: 1999-02-26)

    This thesis is organized in seven independent chapters: I) a description of the structure and reactivity of the metalloproteins of copper and iron which deal with the oxygen processing into living organisms; II) an study ...

    Síntesis y caracterización de materiales poliméricos para la separación no cromatográfica de metales nobles. Separación y determinación de iridio mediante cromatografía líquida y electroforesis capilar 

    Sánchez Navarro, Juan Manuel (Fecha de defensa: 1999-03-17)

    For the selective separation of Noble Metals, different new chelating polymers with the same functional group, based on tri-isobutylphosphine sulphide, have been synthesised. Different spacers between the polymeric matrix ...

    Síntesi de 1-oxaspiro [4.4]nonans polifuncionalitzats i (+-)-andirolactona 

    Planas i Grabuleda, Marta (Fecha de defensa: 1996-03-15)

    Spiro-γ-lactones are widely distributed among natural products, several of them being well known by their interesting biological activities. We describe herein the synthesis of 1-oxaspiro[4.4]nonan derivatives and ...

    Aproximacions sintètiques per a la preparació en dissolució i fase sòlida de llibreries de sistemes herocíclics de 5 membres amb elevada diversitat molecular. Síntesi d'imidazolones, triazoles i imidazoxazoles 

    Heras i Corominas, Montserrat (Fecha de defensa: 1999-07-27)

    According to a strategy based on an Aza-Wittig reaction type, an efficient methodology in solution toward the synthesis of libraries of 2-aminoimidazolones with high molecular diversity has been developed. The strategy is ...

    Utilització de suports polimèrics en processos de separació de metalls valuosos. Aplicacions hidrometal.lúrgiques i analítiques 

    Iglesias Juncà, Mònica (Fecha de defensa: 2000-03-03)

    The present study focuses on the characterization of solid-liquid extraction techniques for the separation and preconcentration of rare-earth elements and precious metals. We developed an impregnated resin with di ...

    Síntesi de nous complexos de Coure i Ruteni amb lligands de tipus tri-N-dentats: estudi de les seves propietats magnètiques i/o electroquímiques 

    Rodríguez Pizarro, Montserrat (Fecha de defensa: 2000-06-20)

    This doctoral dissertation is divided in two different parts. The first one deals with copper complexes and their magnetic properties. The second one describes the synthesis and characterization of a new family of ruthenium ...

    New manganese complexes with nitrogen donor ligands. Catalysts for oxidation reactions 

    Rich Masallera, Jordi (Fecha de defensa: 2012-06-08)

    The catalytic asymmetric oxidation of alkenes has special interest from both industrial and academic points of view. For this reason, catalysts able to perform these reactions in a faster and more effective manner have ...

    Analytical strategies based on inductively coupled plasma sprectroscopy (ICP) and diffusive gradients in thin fims (DGT) techniques for the assessment of environmental pollution indicators 

    Colon i Bosch, Mireia (Fecha de defensa: 2011-02-11)

    In this thesis, simple methods to determine sulfide at low levels (µg L-1) in aqueous samples and sediments by water free hydrogen sulfide vapor generation using a commercially available vapor generation accessory have ...

    Computational modeling of charge transfer in nucleobase-aromatic amino acid complexes 

    Butchosa Robles, Cristina (Fecha de defensa: 2012-06-22)

    The present thesis models nucleobase-amino acid charge transfer reactions, which can serve as base for future computational investigations of charge transfer processes in DNA-protein systems. Guanine and adenine charge ...

    Reactivity of well-defined organometallic copper(III) complexes in carbon-heteroatom bond forming reactions 

    Casitas Montero, Alícia (Fecha de defensa: 2012-06-01)

    This thesis is focused on the unexplored field of organometallic copper(III) chemistry. Arylcopper(III) complexes have been proposed as key intermediates in Ullmann condensation reactions that consist in the coupling of ...

    Metalls de transició en la formació d'enllaços carboni-carboni: cicloaddicions [2+2+2] catalitzades per Rh(I) i acoblaments creuats catalitzats per Pd(0) i Ni(0) 

    Brun Massó, Sandra (Fecha de defensa: 2012-04-27)

    Carbon-carbon bond formation reactions catalyzed by transition metals represent one of the most versatile and efficient strategies in organic synthesis. The catalytic transformations contribute to the development of ...

    Synthesis of unusual alpha-amino acids and study of the effect of their incorporation into antimicrobial peptides. Total synthesis of biactive marine natural products and analogues thereof 

    El Marrouni El Ghazaoui, Abdellatif (Fecha de defensa: 2012-04-13)

    The principle theme of this thesis was the synthesis of bioactive compounds. To this end, this work was focus on two main projects. The first one, which was carried out in the Department of Chemistry of the University of ...

    Managanese and dicopper complexes for bioinspired oxidation reactions: catalytic and mechanistic studies on C-H and C=C oxidations 

    Garcia Bosch, Isaac (Fecha de defensa: 2011-12-20)

    Enzymes are high-weight molecules which catalyze most of the metabolic processes in living organisms. Very often, these proteins contain one or more 1st row transition metal ions in their active center (Fe, Cu, Co, Mn, Zn, ...

    Reaccions de cicloaddició [2+2+2] catalitzades per Rh(I) 

    Garcia López, Lídia (Fecha de defensa: 2012-02-24)

    The development of new chemical processes and efficient catalysts for the formation of carbon-carbon bonds is an important topic in organic chemistry. In particular, the [2+2+2] cycloaddition reaction involving different ...

    Synthesis of antimicrobial peptides derived from BP100 and BPC194 

    Güell Costa, Imma (Fecha de defensa: 2012-01-27)

    In the present PhD thesis we studied the solid-phase peptide synthesis of antimicrobial peptides derived from the lead peptides BP100 and BPC194. First, peptides derived from BP100 containing D-amino acids at different ...

    Efecto de la aplicación de altas presiones hidrostáticas en un producto de origen animal, el jamón curado y en un producto vegetal, el nabo 

    Clariana Orduña, Maria (Fecha de defensa: 2011-12-16)

    High pressure processing is a food preservation technique which can be an alternative to heat treatment. Pressurization, in theory, produces changes in organoleptic properties and antioxidant compounds to a lesser extent. ...

    Rhodium(I) catalyzed [2+2+2] cycloaddition reactions: experimental and theoretical studies 

    Dachs Soler, Anna (Fecha de defensa: 2011-07-29)

    The [2+2+2] cycloaddition reaction involves the formation of three carbon-carbon bonds in one single step using alkynes, alkenes, nitriles, carbonyls and other unsaturated reagents as reactants. This is one of the most ...