CHEMISTRY (9)

Author: SANTIAGO RIVAS SANDRA.
Year: 2006.
University: SANTIAGO DE COMPOSTELA [www.usc.es].
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: The study of the concentration of trace metals level, ie between ppm and ppb, in the various agencies is relieved importance both for toxicity by the essentiality they can submit them. Because of the great interest in recent years raises everything related to the determination of metals linked to a type of protein characteristics, called metalotioneínas (MTs, Metallothioneins), the primary objective of this thesis has been the quantification of metals associated with them . Our study focused specifically on the MTs present in the mussels, called in this case being the mussel one invertebrate, proteins similar to metalotioneínas (MLPs, Metallothionein Like Proteins). Such metaloproteínas is characterized primarily by introducing a low molecular weight and metal joints via disulfide bridges with zinc, copper and cadmium. The presence of metals in the environment induces biosynthesis of these proteins. Therefore, the determination of the concentration of metal in them is to make a direct estimate of metal pollution in a particular place. Another feature to emphasize is that these proteins have several isoforms, the most abundant the MT-Iy the MT-II, which makes it attractive speciation and the determination of metals associated with each of them. The agency is under study mussels because of the importance that is bioacumulador being a good biomarker metal pollution of the marine environment. In addition, the economic importance to the cultivation of mussels has on our community, the second world producer, makes it necessary to conduct comprehensive studies on this important product.

Author: Carrillo Fumero Romen.
Year: 2006.
University: LA LAGUNA [www.ull.es].
Place of defense: Inst. Univers. Antonio González.
Place of preparation: Instituto Universitario de Bio-Orgánica António González.

Summary: It has been designed and synthesized two families of receptors chiral cation, both starting as a fundamental unit of cis-2-alquil-3-oxi-tetrahidropirano from galactose. The first family consists of macro-oligólidos. They have an alkali cation complexation moderate, through a folding receptor around cation. In addition, some of these receptors have the property of forming nanotubes added in solid phase. On the other hand, another family of receptors was designed with a view to optimizing the original design to achieve discrimination between two enantiomers of a chiral cation, in particular ammonium salts of amino acids. Fortunately we found a receiver that displays a great discrimination between the two enantiomers of amino acids with aromatic chain, in particular tryptophan. By studying the system found that the receiver is folded, as complexed free, and that there is an interaction CH-pi intramolecular. In addition to the D-enantiomers those aromatic amino acid chain, establishing another interaction CH-pi, this time intermolecular of vital importance to the phenomenon of chiral recognition. Both interactions could be quantified. In addition, we studied so qualitative and quantitative effect isotope deuterium not covalent to replace hidrógenos involved in the interactions CH-pi described by deuterios. Finally, they found the great influence of anion in the entire process of complexation, hypothetically associated to a further interaction between the aromatic part of the substrate and the anion, or not strengthen interaction CH-pi intermolecular.

Author: CRUZ LOPEZ PATRICIA G..
Year: 2006.
University: LA LAGUNA [www.ull.es].
Place of defense: INSTITUTO UNIVERSITARIO ANTONIO GONZALEZ.
Place of preparation: INSTITUTO UNIVERSITARIO DE BIOORGANICA ANTONIO GONZALEZ.

Summary: In order to conduct a study of metabolites produced by the microalgae Prorocentrum belizeanum perform artificial cultivation on a large scale of this body from a sample of cells donated by courtesy of D. Santiago Fraga. Thus we got a total of 1000 liters of culture, and the cells contained in this volume got an extract of acetone (22 g). From extract and acetone aislamos metabolites known acid Okadaico and Metil-Okadaato, along with four new derivatives acid Okadaico: diol ester C10 Acid Okadaico, DTX-5c, acid epi-Okadaico and acid Belizeánico. The diol ester C10 Acid Okadaico is the first example with a chain diol ten carbons, since so far, derivatives acid Okadaico have only been found diol chains with a maximum of nine carbons. The compound DTX-5c proved to be the first group of toxin water soluble toxins isolated from a species other than P. Maculosum, because so far all compounds of this group (DTX-4a, DTX-4b, DTX-5a and DTX-5b) had only been found in species P. Maculosum. On the other hand, the acid 19-epi-Okadaico, introduced as amended with respect to acid Okadaico epimerización in carbon C-19, which cam associated with a change in the conformation of the compound. Therefore, we conducted a study conformacional of this metabolite combining computational methods and NMR, which led us to propose a conformation for this new metabolite different to the one introduced acid Okadaico. Because of this observation also perform tests of inhibition of the enzyme acid 19-epi-Okadaico both PP1 with PP2A, and the percentage of inhibition were similar to those of acid 19-epi-Okadaico in him if the PP2A, while with the PP1 note light deiferencias. The values were obtained, we drew attention when one takes into account the change conformacional Acid 19-epi-Okadaico with respect to acid Okadaico, so we do an analysis for the complex thermodynamic acid 19-epi-Okadaico-PP1, results show that the ligand is not bound to protein as proposed because the value of Kd quite different from estimated Ki. Of the metabolites were isolated, acid Belizeánico is that more has changed its skeleton with regard to acid Okadaico, because in this compound has not been formed ring oxolano C or oxano D. The amendment introduced acid Belizeánico comes together for the formation of two new chiral carbon, C-16 and C-19. To try to propose estereoquímica of these at the same time shaping the metabolite raised a study conformacional in which computational methods were combined again with NMR. Following this study proposes a configuration S * to C-16, while for C-19 was not possible to obtain a proposal. However, the comforamción of this molecule in solution is similar regardless of whether the crabono C-19 is S or R * *. The isolation of this metabolite was found to be of great interest because it supports the proposed Murata, whereby ring C, D and E are formed by a ciclación nucleofílica from intermediate epoxide. However, the acid Belizeánico reduction of carbonyl group at C-19 prevents the formation of this system espiro in carbon, which agrees with the estereoquímica C-16 (S *) opposite the acid Okadaico because that does not occur ciclación. Finally, in a mestra concentrated acid Okadaico (30 mM) note the presence of a species aggregate comprises four uniddaes Acid Okadaico, and before the data NMR and mass suggest that we are within formed by two dimers Acid Okadaico. As far as using the method proposed by Comeu et al. We propose a shape for the addition fitting the experimental data.

Author: García Silvestro Gonzalo.
Year: 2006.
University: LA LAGUNA [www.ull.es].
Place of defense: Facultad de Química, Universidad de La Laguna.
Place of preparation: Facultad de Química.

Summary: Among the various types of fuel cells, the most suitable for powering portable devices, electric vehicles and transportation, are the polymer electrolyte (PEMFCs) and direct methanol (DMFCs) due to their low temperatures of work (60 - 100 Â ° C) and its rapid implementation. The catalysts used in the anode more of these cells are platinum and its alloys. Given that the catalysis is a surface phenomenon, one aspect to consider in the design of catalysts is to provide a high surface area. To this end, the active phase of the catalyst is dispersed on a support driver, which in this case is coal. However, the development of PEMFCs, from the viewpoint of electrocatalizadores is limited by the poisoning of the anode catalyst for CO, which is present as an impurity in the reformed gas, which is used as a source of H2 for these cells. Therefore, at present much of the research are directed to the preparation of CO tolerant anodes. In the presence of 50-100 ppm CO in the fuel alloys Pt-Ru supported in coal have shown a electrocatalítica greater than the pure Pt. In the case of DMFCs, alloys Pt-Ru supported in coal have also been widely used because it increases the speed of oxidation of methanol respect to Pt, and the relationship of atomic Pt: Ru 1:1 most employed . The yield on DMFCs is limited by various problems, both kinetics of the reactions electródicas as transfer of methanol through the membrane from the anode to the cathode. In fact, a good catalyst for the anode of these cells has to combine a high activity toward the dehydrogenation of methanol with improved tolerance to poison catalytic (CO). To improve the performance of electrocatalizadores, there are several factors to consider: changes in the distance interatómica Pt-Pt the effect of the alloy, the composition of the latter, surface area, and consequently, the size of grains, and the effects electronic affecting configuration Pt, as well as the possibility of action mechanism bifuncional. In relation to the materials used in the cathode of these devices, Pt metal is showing the greatest catalytic activity towards the oxygen reduction reaction. We have employed Pt alloys with numerous Transition metal catalysts, in order to improve the catalytic activity, tolerance towards methanol and reduce the cost of the material. Two factors that affect a significant activity of these catalysts are the dispersion and homogeneity in the composition of the alloy. Another area of interest is the development of microceldas fuel. Recent advances in the field of systems microquímicos and technology of fuel cells, together with the increase in demand for efficient sources for portable equipment for domestic use, have boosted efforts to develop equipment based energy generation the electrochemical conversion of fuels and chemicals in fuel cells microfabricadas. We have proposed new synthesis of materials for these devices, with structures mesoporosas (MP) which presents a more promising future. During recent years, there have been synthesized MP metal structures by chemical and electrochemical reduction of metal salts dissolved in the domain of an aqueous liquid crystal. The high activity of the Pt electrode MP towards electrooxidación methanol, only comparable to smooth Pt electrodes, has been attributed to various factors, such as the activation of water molecules, 8 the prese 1ff8 ncia planes cristalográficos appropriate on the the metal surface, or the importance of the existence of parallel tracks reaction. However, so far, there are no studies on site devoted to elucidate the importance of these factors. In this context, the present work has focused on the synthesis and characterization of Pt catalysts and their alloys supported on coal for use in fuel cells at lower temperature (PEMFCs and DMFCs). In addition, it also has carried out the development of new catalysts MP for microceldas fuel. In these materials has been studied the reaction of methanol and its tolerance to CO, applying it to conventional techniques and novel techniques for the in situ physicochemical characterization and espectroelectroquímica respectively. The following physicochemical techniques were used: Analysis by energy dispersive X-ray (EDX) and X-ray fluorescence (XRF). We applied to establish relations of atomic Bimetal of Pt alloys and metal content in coal endured. X-ray Diffraction (XRD). It was used to identify the phases present in the catalysts and to assess the particle size of the crystals of metal scattered in coal. - Transmission electron microscopy (TEM). We used to determine the size, distribution and formation of agglomerates of nanoparticles. - Images were obtained tunneling microscopy (STM) to elucidate the morphology of catalysts MP. In addition to these methods ex situ electrochemical techniques were used to provide an initial understanding of the reactivity of the catalysts. These are: -Electrodo disc rotating (RDE). It used to study the kinetics of the oxygen reduction reaction on the Pt alloys Bimetal supported in coal. - Voltamperometría cyclical (CV). It enabled the electrochemical characterization of materials, the study of the tolerance of carbon monoxide and methanol oxidation, as well as for determining the area electroquímicamente active catalysts. - Were purchased curves cronoamperométricas to establish the efficiency of the catalysts for the oxidation of methanol. The analysis of the processes at the interface electrode / electrolyte is essential for the elucidation of the mechanisms of electrochemical reaction at the interface. Over the past twenty years, the techniques espectroelectroquímicas spot have proved to be adequate tools for the elucidation of the reactions that take place on the surface of electocatalizadroes. However, few studies using these techniques applied to technical catalysts (such as metal catalysts supported on carbon). Moreover, the ability to test these catalysts that have applications for fuel cells and microceldas, gives these techniques even more interest. For these reasons, applied three techniques espectroelectroquímicas spot in these investigations:-spectroscopy by Fourier transform infrared (FTIRS) on the spot. Technical useful for studying the interaction of CO with the surface of electrocatalizador. The differential mass spectrometry differential electrochemical (DEMS), which allows detection of intermediaries or gaseous products generated in the electrochemical reactions. - The deflectometría gradient concentration (PBD) on the spot. It is a technique that allows optical monitor profiles established concentration at the interface electrode / electrolyte during electrochemical reactions. The first investigations that were conducted tried to check the possibilities of FTIRS spot for predicting the behavior of a catalyst in a PEMFCs. So, were synthesized electrocatalizadores of Pt80Ru20, Pt80Os20 and Pt85Co15 supported by reduction in coal with formic acid or borohidruro sodium, and compared their properties espectroelectroquímicas with those of the Pt / C business. It was found that using an experimental design appropriate FTIRS can be used to characterize submonocapas of adsorbatos through desorption in a bath towards potential positive. The VCs due to the oxidation of CO adsorbed were used to normalize the area of the electrodes. The FTIR spectra could be purchased during the oxidation of CO on the technical material in an electrochemical cell, obtaining valuable information on the reactivity, allowing predict their efficiency in a PEMFC. The main adsorbato adsorbed CO was a linear fashion, but also detected small amounts of CO on a bridge linking. Moreover, species COH were detected in the case of Pt80Os20 and Pt85Co15. Moreover, it was established and compared for the four catalysts the beginning of the oxidation of CO to lead CO2. All alloys Bimetal oxidaron CO adsorbed potential more negative than platinum and identified a shift of about 0.20 V towards more negative values. However, the presence of hydrogenated species for catalysts Pt80Os20 and Pt85Co15 predicts that the behavior of the latter must be worse in a fuel cell, as indeed happens. As for the performance of anode, a study was carried out in order to correlate the electrochemical behavior of the catalysts of Pt-Ru / C with the particle size, and therefore the surface area. Different catalysts Pt-Ru / C with crystalline and amorphous structures, and various particle sizes were prepared and characterized fisicoquímicamente. These materials have a high concentration of metallic phase supported on coal, and were synthesized through a colloidal method at low temperature. The amorphous oxide nanoparticles of Pt-Ru were deposited on coal to be reduced below hydrogen in a reactor at different temperatures, in order to obtain crystalline phases with different particle sizes. The activity electrocatalítica towards the oxidation of methanol was investigated in an electrochemical cell between 30 and 60 Â ° C. The results were interpreted in terms of particle size, crystal structure, the degree of alloy and the adsorption of carbon monoxide. The best performance was obtained for catalyst particle size with intermediate (1.6 and 2.2 nm) in the range studied. Moreover, it was observed that the best properties of these catalysts are highly dependent on temperature. Another point considered was the problem of cathode. Activities electrocatalíticas of these materials to reduce oxygen in sulfuric acid in the presence or absence of methanol were investigated through experiments and rotating disk electrode in a station DMFC. The activity of these electrocatalizadores towards the oxidation of methanol were from the experiences of cyclic voltammetry. It was found that the catalyst for Pt9Cr / C, prepared by reduction with NaBH4, presents the lowest activity towards the oxidation of methanol and the best performance for the reduction of oxygen in the presence of methanol, when compared with electrocatalizadores commercial Pt / C , Pt3Cr/Cy Pt-Cr / C. In the field of microceldas fuel, it undertook the synthesis of new catalysts based on Pt. The electrodes in electroplating MP synthesized by modifying Pt and Pt with adátomos of Ru, were evaluated as catalysts for electroxidación CO and methanol. The analysis reveals a high electrochemical activity Mass for electrooxidación methanol, similar to the catalysts supported on coal. However, the high current densities are associated with low eficienc 8 ia in 5bd conversion to CO2, as was established using DEMS in a flow cell with a thin layer configuration (TLFC-DEMS). These results can be understood taking into account the structure of porous electrodes especially accessible MP, where the possibility of readsorción product is partially oxidized low. Finally, we studied the behavior of electrochemical electrodes MP Pt and Pt / C using PBD. It was noted that this technique allows the evaluation of the flow of mobile species in the electrochemical interface of the catalysts, being sensitive to the adsorption of anions from the electrolyte. It was clearly demonstrated during the electrooxidación CO PBD is able to detect the flow of ionic species and soft drinks next to the surface of the electrode.

Author: Miranda Chinea Pedro Oswaldo.
Year: 2006.
University: LA LAGUNA [www.ull.es].
Place of defense: Instituto Universitario Antonio González.
Place of preparation: Instituto Universitario de Bio-Orgánica "Antonio González".

Summary: The chemistry organoférrica has not attracted the attention of organic chemistry. This thesis has been used salts of Fe (III) to assess their behavior before alquinos and also in the reactions liaison alquino-aldehido. Also, have also been used for the synthesis of rings piránicos via the reaction of Prins. This reaction has called powerfully attention of the international scientific community in recent years due to its great capacity to manufacture cyclic structures in a single reaction step. It has also conducted an analysis Structure Activity Relationship of the compounds obtained.

Author: PARREU I ALBERICH ISABEL.
Year: 2006.
University: ROVIRA I VIRGILI [www.urv.cat].
Place of defense: FACULTAT DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA. URV.

Author: SILANES CRISTOBAL IÑAKI.
Year: 2006.
University: PAÍS VASCO [www.ehu.es].
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: This thesis makes a theoretical study (by Quantum Chemistry) reaction mechanism for the propagation stage in the catalyzed polymerization of ethylene pro metalocenos Group IV (Ti, Zr, Hf). We review critically the proposed mechanisms by Cossee and Arlman in 60, and M. Ystenes at 90, concluding that both are of limited versimilitud, to ignore the role of contraion in the reaction. Finally, it examines the inclusion of such a contrarion at the reaction, as well as the differences among the three metals cited, and three routes approximation of the monomer catalyst.

Author: SIERRA IZQUIERDO BORJA.
Year: 2006.
University: PAÍS VASCO [www.ehu.es].
Place of defense: FACULTAD DE CIENCIA Y TECNOLOGÍA DE LEIOA.
Place of preparation: UPV/EHU.

Summary: The report consists of two parts: First is the study of the family of clorofluorometanos (CCl4, CCl3, CCl2F2 and CClF3) by electronic impact on a system EI-MS-TOF to obtain effective sections partial and total ionization, thresholds ionic appearance, distribution of kinetic energy. Have been proposed with the data collected possible avenues disociativa ionization of the same ions. In addition, it has proven the validity of theoretical calculations used to obtain more effective sections for total ionization molecules in the presence of heavy atoms in its interior, as is the case with Cl. Secondly, it has been designed, assembled and optimized a system for ablation of metals at different fluencias where you can study as a first resutlados power distribution by different ions depending on the load pass for an electrostatic energy analyzer. As detector uses a series of plates in a multichannel system TOF-MS. The objective of this system is to conduct studies of laser ablation and study the mechanisms that occur in the process. In addition, adjustments have been made to theoretical equations to help understand the mechanisms.

Author: Sala Román Xavier.
Year: 2006.
University: GIRONA [www.udg.es].
Place of defense: Universitat de Girona-Facultat de Ciències.
Place of preparation: Universitat de Girona.

Summary: Synthesis of a new family of complex Ru (II) with ligands type tioeter. Structural Characterization, espectroscópica and electrochemistry. Applications in capmpos of electrocatálisis i reactions replacement foto-inducidas. Synthesis of new chiral complexes of Ru (II) with ligands oxazolínicos or polipiridílicos. Comprehensive structural characterization by NMR, Diffraction of Rayos-Xy theoretical calculations DFT. Implementation of the complexes synthesized in oxidation and reduction reactions asymmetrical.

Author: SIRÉS SADORNIL IGNACIO.
Year: 2006.
University: BARCELONA [www.ub.es].
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: Paracetamol, acid clofibrico and clorofeno are representative examples of three of the most therapeutic groups traded PPCPs (Pharmaceuticals and Personal Care Products) around the world: anti-inflammatory drugs not esteroídicos, drug regulators in blood lipids and drugs antimicrobials, respectively . The PPCPs, including pharmaceuticals and personal hygiene products, as a group of substances to which they had devoted little attention until relatively recently. Currently, these compounds are also classified as POPs, as they are introduced into the environment on a continuous level ng-ug L-1 worldwide. The contamination of the aquatic environment in particular is especially disturbing when you consider the importance of the water cycle in the preservation of the planet and delos beings who inhabit it. The risk and the potential effects of these pollutants is currently under study, and for the moment there is enough data to suggest strongly which is the real danger. Today, the approach taken in the field of treating wastewater containing various pollutants is to combine successive procedures, introducing special technologies that are very affective against compounds. Therefore it is necessary to develop more powerful and effective methods. To that end, several processes which include electrochemical oxidation Anódica and Advanced Oxidation Processes Electroquímicos to be presented as an attractive alternative compatible with the environment, as the main oxidizing species involved is the hydroxyl radical. That would have made different experiments combining several anodes and cathodes, using different catalysts. Through the reaction of Fenton, processes electro-Fenton (FE) and fotoelectro-Fenton (FSP) cathodes diffusion of oxygen or carbon felt let produce hydroxyl radicals within the dissolution treated. In oxidation anódica anodes with platinum (Pt) or diamond doped with boron (BDD), the oxidizing agent is the same, although it is found quimisorbido or fisorbido respectively, on the surface of the electrode. For paracetamol has made a study of the processes and EF FSP with a Pt anode and a cathode diffusion of oxygen, and has found the role they have different complexes formed between lso metal catalysts used and carboxylic acids generated during degradation. It has been applied oxidation anódica with two types of anodes, Pt and BDD, and a graphite cathode. In the case of acid clofíbrico has introduced the combination of the anode to the cathode BDD diffusion, which leads to a significant improvement of results. This study has highlighted the importance of the different species oxidizing hydroxyl radical. Finally, it has conducted a thorough study of the degradation of clorofeno through EF, using a cathode diffusion of oxygen or a coal felt as cathodes. This has been able to explain the system catalytic Fe3 + / Fe2 + on the effectiveness of the cells with anodes Pt and BDD. Ultimately, the roads have been proposed in response to electrochemical degradation of paracetamol and acid clofibrico, and has demonstrated the complete elimination of the intermediate end of clorofeno.

Author: GIL SÁNCHEZ LUIS.
Year: 2006.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: Dep. Ingenieria Electronica.
Place of preparation: Universidad Politécnica de Valencia.

Summary: In this dissertation develop electronic systems as they are sensing element multiple electrode electrochemical nature. Each of the electrodes has a non-specific sensitivity to some of the parameters or chemical compounds in the samples analyzed. The set of electrodes made a series of signals to be analyzed together, to get conclusions of interest, usually in complex samples discrimination or quantification of some of its components. This type of measurement systems are called electronic languages. A measuring system developed using sensors type potenciométrico and pastes are built with technology thick layer (Thick-Film), and also by simple metal electrodes in a pure state. With this method can be achieved devices with features simplicity of construction, mechanical robustness, ease of handling and low cost. With the signals obtained are applied pattern recognition techniques, such as principal component analysis, artificial neural networks, as PLS predictive techniques, and so on.

Author: nolis fañanas pau.
Year: 2006.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: autonoma de barcelona.
Place of preparation: autonoma de barcelona.

Author: AMIGO RUBIO JOSÉ MANUEL.
Year: 2006.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: FACULTAD DE CIENCIAS UAB.

Summary: The aim of the thesis is the application of methodologies quimiométricas multidimensional analysis of enzymatic reactions. The enzymatic reactions studied have application in the fields of chemical analysis in biological matrices and fermentation processes on an industrial scale. Specifically: 1) Study of the reaction mechanism in biological matrices and calculation of the constants in enzymatic reactions complex. It explores the catalysis of mixtures of hipoxanthine, xanthine and uric acid with xanthine oxidase, in a controlled environment and in human urine. In addition, it was determined quantitatively the above analytes in human urine. The kinetic profiles were recorded using a spectrophotometer Ultravioleta-Visible equipped with a detector diodes. In this spectrophotometer docked a system of flow interrupted stopped-flow. To maintain constant temperature using a module "Peltier." 2) Establishment of a methodology for real-time control of bioprocesses. The system studied is the production of enzymes lipases by the microorganism Pichia pastoris. The measures fluorescence were conducted using a multi-dimensional fluorescence sensor connected to the bioreactor through a quartz window. 3) An objective unrelated to the monitoring of enzymatic reactions, is the development of a practical laboratory aimed at students of higher grades of Science degree in Chemistry for the introduction to the methods of resolving curves and chemometrics in general. We have obtained the following general conclusions: 1) The introduction of the restriction kinetic model of the system studied in the algorithm MCR-ALS has led to a new working methodology, called HS-MCR-ALS. Its application to kinetic enzyme system has made it possible: The study of the enzyme system in the presence of interfering spectral. The elucidation of the kinetic model, as the previously described in the literature did not include the degradation of uric acid. The determination of kinetic constants of the model postulated, both in half tamponado composition known as urine. 2) have been implemented and compared various methods, bi - or three-dimensional multivariate analysis for the quantitative determination of xanthine and uric acid hipoxanthine synthetic mixtures and in human urine Doped. The results in implementing quantitative HS-MCR-ALS are comparable to the results obtained through other algorithms dimensional, 3W-PLS1 and 3W-PLS2, and the classic two-dimensional algorithms, PLS1 and PLS2, with a minimal amount of samples pattern. 3) It has established a new working methodology for real-time control of processes monitored by fluorescence. It is based on the non-invasive monitoring of the reaction by a fluorescence probe multidimensional and in the treatment of the signal recorded by the algorithm PARAFAC. From model PARAFAC applied to bioprocesses developed under normal conditions, we obtain an estimate of the spectral profiles of fluoróforos and the evolution of its signal. The analysis of residual of this model allows for control limits (criterion Q). Based on that information, was monitored and controlled in real time a new batch of bioproceso, being possible to determine the end point of the production and metabolism of lipases total substrate without the need for off-line measures of the analytes of interest. 4) has been studied the evolution spectrophotometric acid 8-hidroxiquinolina-5-sulfónico with pH as a practical laboratory for the introduction of the algorithm MCR-ALS students from the higher grades of Chemical degree. This practice provides instructions on how to use the data obtained in the valuation in order to implement MCR-ALS a simple way and didactic.

Author: GARCÍA MONTAÑO JULIA.
Year: 2006.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: UNIVERSIDAD AUTÓNOMA DE BARCELONA.
Place of preparation: UNIVERSIDAD AUTÓNOMA DE BARCELONA.

Summary: The textile industry produces large amounts of waste water with high content of organic matter and color. Due to the environmental threat posed its refractory nature, arises the need for treatment prior to discharge. The biological processes, physical and chemical conventional ineffective in bleaching and complete mineralization of these effluents. Alternatively emerge Advanced Oxidation Processes (PAOs), mainly based on the generation of hydroxyl radical (HO) highly reactive. They can be applied in isolation or in combination with biological treatments with the aim of reducing their high consumption of energy and reagents. Among the different PAOs available, the processes of Fenton, and particularly processes foto-Fenton (based on the generation of OHA by the addition of hydrogen peroxide and ferrous salt in aqueous solution) represent the best choice because of its high efficiency and low cost. Additionally, processes foto-Fenton can be carried out under solar radiation, providing new economic and environmental advantages. This dissertation focuses primarily on the implementation process foto-Fenton as a prelude to the degradation solutions azo dyes reagents biorrecalcitrantes, with the aim of generating a new effluent consistent with an aerobic biological treatment subsequent lower cost and environmental impact that early. The evolution of key parameters such as color, total organic carbon, aromatic, toxicity, biodegradability, the nature of the intermediate degradation, as well as the effect of the source of radiation (artificial light, sunlight), the temperature , reaction time and concentration of reagents, provide information about conditions for coupling PAO-tratamiento biological. The results confirm the suitability of the ODP proposed for this purpose, both at laboratory and pilot plant. Through the process of foto-Fenton applied oxidation under mild conditions, the solutions under consideration are colorless, biodegradable and non-toxic nature. Thus, the combined treatment foto-Fenton-tratamiento biological aerobic degradation allows complete. The sunlight as a source of radiation in the process of foto-Fenton provides the best results. Moreover, the sequence seems to begin by oxidative bleaching break azo group followed by degradation to form aromatic aliphatic -dando place carboxylic acids with the formation of CO2 and H2O- or triazine ring recalcitrant nature. An important part of the hetero-atoms present in the original molecule appear as final products of inorganic nature innocuous. Work is expanded to a study of the economic and environmental sequential process foto-Fenton (artificial light) -tratamiento biological. The environmental assessment has been conducted by the tool Analysis Lifecycle. Compared with the processes simple foto-Fenton under artificial light and foto-Fenton under sunlight, combination therapy is the best choice in both contexts. The greatest impacts are associated, in this order, the consumption of hydrogen peroxide and energy to feed the artificial light. Accordingly, and in response to the results obtained previously, it is possible to conclude that the process of foto-Fenton assisted with sunlight as pretreatment of a biological process would be the best option in terms of effectiveness, environmental impact and operational costs. Finally, as an alternative to the strategy of aerobic oxidation química-tratamiento biological, ODP is used as a post anaerobic biological process. The PAOs considered are the ozonisation and process foto-Fenton. The results demonstrate the suitability of the proposed sequence, obtaining better levels of degradation through the process with ozone. These resu 8 ltados s 2fe on special interest in future applications for wastewater treatment textile real.

Author: Ibáñez García Núria.
Year: 2006.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: Facultad de Ciencias.
Place of preparation: Universidad Autónoma de Barcelona.

Summary: The miniaturized components are a reality that is with us and facilitates our every day in a subtle way. The clearest example is the advances in microelectronics that have allowed the development of both the consumer electronics and the new information technologies. This trend, however, has also been evident in other areas of knowledge such as biology, medicine or chemistry. In the field of chemistry, and especially from the 90's, has made a major scientific effort to obtain micro devices that allow us to carry out the analysis of certain parameters of interest, such as environmental pollutants . Using microanalizadores brings a high number of advantages, such as ease of production on a large scale (and the consequent reduction in costs), low consumption of reagents used, low volume of waste generated (due to the small size of the device) analysis short time, as well as portability, which allows the user to perform in-situ analysis places where hardly could put a team of large and obtain real-time information. There are various techniques and materials used to carry out the miniaturization of chemical analysis systems. The silicon and glass have undoubtedly been the most widely used materials for this purpose, not only because of its appropriate physicochemical properties, but also to the high level of development they have acquired their associated technologies. In recent times, however, the polymers have taken over as material for microfabrication due, in particular, to its low cost. In order to overcome certain limitations found in classic materials and in its associated technologies, in this thesis has opted for the use of an alternative technology called LTCC (Low Temperature Co-fired Ceramics) or ceramic green. The use of these materials gives us great versatility in the design and build miniaturized analyzers. First, the devices can be manufactured without the need to work in strictly controlled laboratory conditions, such as cleanroom or highly qualified staff. They can be used both microfresadoras as laser equipment and the process of prototyping is very short. Additionally, the methodology multilayer design allows very easily device with complex three-dimensional structures. This simplifies extraordinarily miniaturization and integration of the different stages of pretreatment of the sample (mixed reagents, separation, preconcentration, etc..) That are needed to carry out certain analysis, and the monolithic integration of the detection systems. This thesis presents a new methodology overall manufacturing systems analysis miniaturized we applied to the design of microanalizadores environment for the control of water quality of both rivers as water distribution networks drinking. Thanks to its versatility, the new methodology has enabled manufacturing integrate different types of detectors such as electrochemical (potentiometric and amperométricos) or optical (espectrofotométricos and luminescent). We have built microanalizadores for parameters such as ammonium ions, nitrate, nitrite, and phosphate that are key to monitoring the process of eutrophication. At present, using this technology, also have developed devices for determining persistent organic micropollutants.

Author: Martí Ortega Nuria.
Year: 2006.
University: VALENCIA [www.uv.es].
Place of defense: ESCOLA TÈCNICA SUPERIOR D' ENGINYERIA.
Place of preparation: DEPARTAMENTO INGENIERÍA QUÍMICA (E.T.S.E.).

Summary: The anaerobic digestion now represents the most advantageous option for the stabilization of sludge generated Stations Wastewater Treatment Plants (WWTP) in size medium and large. Moreover, the recovery and recycling of phosphorus has been gaining importance in recent years because it is a limited resource. Once used, most of the phosphorus becomes part of the wastewater, and the recovery of phosphates present in them has been proposed as an option to boost recycling. One of the technologies presents major advantages is the recovery of phosphorus content in the flow of supernatant from the digested sludge dewatering by crystallization in the form of estruvita. This process also allows to obtain a sound that is useful as fertilizer, controlling nutrient concentrations recirculadas to head plant. The work dealt with in this thesis aims to highlight the influence that this strategy of operation of the line of sludge on the precipitation of phosphorus compounds in anaerobic digesters, with the aim of establishing the best solution to the serious problems associated with the formation of precipitates taking place in many plants. Moreover, and in line with current trends in sustainability, managing line treatment of the sludge in a WPP must pursue in addition to the stabilization of sludge, nutrient recovery for reuse, in turn minimizing the operation and maintenance costs.

Author: FUNEZ DE GREGORIO ANTONIA.
Year: 2006.
University: CASTILLA-LA MANCHA [www.uclm.es].
Place of defense: FACULTAD CIENCIAS QUIMICAS CIUDAD REAL.
Place of preparation: FACULTAD CIENCIAS QUIMICAS.

Summary: The refining industry is being amended due to the various requirements imposed by the market and environmental legislation, which has led to the reduction in petrol content of aromatics and oxygenates, among others, which entails a loss of octane gasolines. A very interesting alternative to compensate for this loss in the octane number, is the increase in the content of alcanos Tangled in petrol, which have a higher octane number that alcanos linear. Thus, in this investigation, we studied the isomerization of n-octano liquid catalysts using dual-purpose. First, we studied the influence of the presence of the binder on the catalytic activity of catalysts based on zeolites USY, mordenite and beta, with platinum as a function hidrogenante-deshidrogenante. In all cases, the presence of the binder resulted in a decrease of converting n-octano due to the neutralization of acidic centers strengths of the zeolites by cations Na + of bentonite clay and the partial blockage of the micropores of the zeolites by the binder and aluminum species extranet (EFAL) created during the agglomeration process. In the comparative study between platinum and palladium catalysts, it was observed that with the former, reached securities conversion n-octano higher than those obtained with impregnated with palladium. This fact is linked with the higher values of metal dispersion presenting platinum catalysts. Next, we studied the influence of the reaction conditions in the hidroisomerización of n-octano liquid using catalysts zeolíticos based on zeolites USY, mordenite and beta, with platinum as a function hidrogenante-deshidrogenante. It was found that the conversion of n-octano increased in doing so the temperature and the relationship catalyst / n-octano. However, the increasing pressure growing concentration of hydrogen in the system, which moved the balance of the reaction to octene octane. From the data obtained, was raised and resolved a kinetic model. The coefficients of speed and the activation energies calculated, were significant from a statistical point of view, and obtained a good agreement between the experimental results and predicted by the model. Finally, we studied the hidroisomerización a fraction from the distillate of a naphtha refinery and the effect of the combination of two metals on the same catalyst. To do so, were used catalysts based on the zeolite beta, impregnated with Pt / Ni. The total acidity of the catalysts bimetálicos decreased with the increase in the burden of nickel. The greatest activity was observed for catalyst PtBETA. The presence of platinum in catalytic converters bimetálicos led to a higher catalytic activity to high response times. With all catalysts reached a high conversion of aromatic compounds. Finally, the determination of octane number (RON) of the products obtained, indicated an increase of this parameter with respect to the food, because of the high amount of isoparafinas and naphthenic compounds present in the products.

Author: GALLEGO GOMEZ BEATRIZ.
Year: 2006.
University: CASTILLA-LA MANCHA [www.uclm.es].
Place of defense: FACU. DE CIENCIAS DEL MEDIO AMBI. TOLEDO.
Place of preparation: FACULTAD DE CIENCIAS DEL MEDIO AMBIENTE. TOLEDO.

Summary: In the context of Chemical Organometálica, derivatives ciclopentadienilo elements of the first groups of transition, which are complex display features structural and reactivity enabling the discovery of new modes of reaction. The presence of acids and metal centers in high oxidation state makes can participate in many important catalytic processes and estequiométricos based on the formation of links CC and the activation of links CH. The use of ligand ciclopentadienilo group voluminous capacity giver sigma and pi, relieves low electron density of the metal while blocking, in a way, the area of coordination thereof, which may limit their catalytic activity, but simultaneously allows stabilize intermediate species whose characterization aid to a better understanding of the mechanism by which they operate. The purpose of this Doctoral Thesis is the study of various ligands that enable the synthesis of titanium complexes very electrofílicos and, in turn, sufficiently stable, and the study of the reactivity of the compounds synthesized both in formation processes links CC and its application to the synthesis of complex heterometálicos. Throughout this work we want to see to what extent the characteristics estéricas and electronic ligands of the employees can change the reactivity of titanium atom. This report is divided into four chapters, each of which begins with a brief introduction, a history book and continues with the discussion of the results, which impacted on the methods of synthesis and characterization of the compounds prepared. Finally, it includes the pilot and bibliographies. In the first chapter of this report describes the synthesis of a new titanium carboxylate complex [Cp * TiMe ((O2C) 2py)]. This has been used acid dicarboxílico (HO2C) 2py which has a nitrogen atom giver in the pyridine ring which allows the stabilization of these complexes. In this type of ligands are called ligands such as "clamp". Moreover, it has explored the reactivity of this derivative alquílico face isocianuros and water. Finally, it has addressed the synthesis of complex heterometálicos by reaction of titanium with rent [M (OH) (COD)] 2 (M = Rh, Ir). The second chapter describes the synthesis of complex halo and alkyl monociclopentadienilo titanium using alcohol (HOCH2) 2py. From the resulting alkyl alcóxido, has been studying the reactions of protonolisis liaison metal-alquilo when using reagents acids as water or alcohols. Also, have been synthesized complex heterobimetálicos titanium with rhodium and iridium. In the third chapter of this report contains a summary of a series of cationic complexes of titanium with groups triflato and groups arilborato. Have also been studied complex heterobimetálicos cationic titanium aluminum, rhodium and iridium in the group triflato serving as anion. The final chapter describes the synthesis and characterization of complex monociclopentadienilo titanium with ligands silóxido and studying their behavior as a catalyst epoxidación of ciclohexeno in the presence of terc-butilhidroperóxido.

Author: Marqués López MMa. Eugenia.
Year: 2006.
University: SEVILLA [www.us.es].
Place of defense: Facultad de Biología.
Place of preparation: Facultad de Química.

Summary: Chapter I: It has developed a methodology synthesis diastereoselectiva of 4-alquil-3-aminoazetidin-2-onas consistent only in two stages: (1) Cycloaddition [2 +2] between N N-dialquilhidrazonas chiral of aliphatic aldehydes and aminocetenas and (2) Elimination of chiral auxiliary break through oxidant NN liaison with perácidos of N-dialquilamino-b-lactamas resulting. Studies conducted computational support a mechanism for this type Staudinger reaction cicloadición [2 +2]. You can choose the configuration on the b-lactamas obtained by modifying the temperratura reaction. It should be noted that the trans selectivity observed at high temperatures is a complement to existing methods of cicloadición esterocontrolada of iminas aliphatic to cetenas, leading to cis derivatives. The availability of the two enantiomers from chiral auxiliary employee increases the potential of this methodology because it provides the cicloaductos with the absolute configuration desired. The opening of the heterocycle of synthesized products leads to a corresponding, b-diaminoácidos, components of various compounds of biological interest. Chapter II: The N, N-dialquilhidrazonas have a reactivity electrofílica allowing their use as substrates in reaction type Strecker. It has developed a version highly diastereoselectiva using N, N-dialquilhidrazonas aliphatic arising from the (2S, 5S) -2.5 -difenilpirrolidina as chiral auxiliary. In addition, it has undertaken the process of adding cyanide to N, N-dialquilhidrazonas aliphatic using tioureas aquirales as organocatalizadores, resulting products cianación with excellent yields. Finally, it has made the first type Strecker reaction in water, without a cosolvent or catalyst, producing pure products with yields cuantitavos, short reaction times. This procedure has an obvious attractive from an economic point of view and environment to catalog the prodecimiento as "green chemistry".