CHEMISTRY, 8

Author: LLAudy Fernández María del Carmen.
Year: 2006.
University: ROVIRA I VIRGILI.
Place of defense: Facultat de Enología Universitat rovira i Virgili.
Place of preparation: Facultat de Enología.

Summary: This thesis deals with the study of the astringency of red wine and some of the factors that condition. First reflected the work done to develop a methodology that would allow the measure astringency of wine in an objective and reproducible using a protein readily available: egg albumin, and patterns of tannic acid. Secondly describes the influence on the astringency of some of the non-phenolic components of the matrix (wine), such as pH, concentration of ethanol and glycerol and the use of gum arabic as an example of polysaccharide. Our results indicate that within the normal ranges of pH, concentration of ethanol and glycerol, possible variations of astringency would be moderate. By contrast, the addition of gum arabic wine produces a significant decrease of astringency. Thirdly detailed comparative study of egg albumin with all salivary proteins compared to tannic acid (tannin used as a template), proantocianidinas different monomer composition and varying degrees of polymerization and commercial wines from different places. Noting that both models of proteins have a high statistical correlation, suggesting a similar behavior in front of the tannic acid and proantocianidinas, despite presenting different affinities. The study of wines gave statistically similar results by more than 80%. So we believe that, given the methodological difficulties inherent in the use of saliva proteins, the use of egg albumin as an agent Precipitating seems to be a good solution for the objective determination of astringency in the wine. Finally describes two experiences where applies the methodology developed: 1 The influence of long maceration on the phenolic compounds and astringency on the skins, seeds and raspones three different degrees of maturity. The most important conclusions of this experiment have been corroborate that, as the grapes mature, diminishes the contribution of tannin from seed and, in parallel, decreasing its astringency. By contrast, in furs and raspón, providing tannin rises to ripen the grapes while decreases astringency. The tannins from the skins and the raspones are released quickly toward stabilizing the day 5 of maceration. Rather tannins of the seeds were solubilizan more slowly and take longer to stabilize, especially when the grapes are green. These results should be taken into account when determining the maceration time: when the grapes are ripe good time maceration should be selected depending on the style of wine you want to produce. However, when the grapes have ripened well, a long maceration is not desirable as it would lead to excessive extraction of tannin seed, which would result in too astringent wines. 2 The impact of microoxigenación before raising barrel on the astringency of red wine. This experiment was concluded that the wines microoxigenados would be levied with a color slightly less intense and slightly more advanced, presenting a greater concentration of antocianos, especially monoglucósidos and its derivatives acetilados and cumarilados. Surprisingly no difference in the levels of vitisinas between wine microoxigenado before upbringing on which was only in the barrel, but if there were differences in the degree of polymerization average of the proantocianidinas. In both experimental groups, there was a clear decline in respect astringency wine game. This decrease was significantly greater in the wine microoxigenado. According to these results the implementation of the microox 8 igenació 359 No wine before the aging in oak casks would be advisable in very astringent wines such as wine press or wine from grapes not very mature.

Author: CALVIÑO PEREZ ELYN.
Year: 2006.
University: LA LAGUNA.
Place of defense: FACULTAD DE FARMACIA, UNIVERISDAD DE LA LAGUNA.
Place of preparation: UNIVERSIDAD DE LA LAGUNA.

Summary: This dissertation presents a new method of analysis for the diagnosis of gastrointestinal diseases, attending with a marked increase in the production of hydrogen gas as a metabolic product of anaerobic bacteria that inhabit the human colon, specifically intolerance lactose and intestinal infections. This method is based on the extent of potential biological hydrogen generated by the product of the anaerobic fermentation, eliminated in the urine. This has been used two sensors hidrógenos, the first is a sensor potenciométrico measuring gas phase and that it is an experimental prototype developed by our research group, and the second a sensor amperométrico which measures within the dissolution , marketed by the company Unisense.

Author: Sotoca Usina Enrique.
Year: 2006.
University: VALENCIA.
Place of defense: Facultad de Química.
Place of preparation: Facultad de Químicas- Universidad de Valencia.

Summary: My doctoral thesis consists of the following items: a) study the reactivity of dianiones of carboxylic acids with ditioacetales of perfluorocetena. 1) The reaction of dianiones of carboxylic acids with ditioacetales of perfluorocetena has been optimized, obtaining the products resulting from the replacement of vinyl fluoride. 2) The development of the reaction has been optimized, which simplifies the maximum isolation from the reaction products with high purity. 3) The reaction has been extended to carboxylic acids, a b-insaturados, and through analysis of the products has proposed a reaction mechanism. 4) The methodology has been extended to carboxylic acids orto-metilarénicos. B) A study of the reactivity of dianiones of carboxylic acids with a-clorocetonas cyclical. 1) It has been observed adding dianión the carbonyl group of electrófilo, as in the a-clorocetonas linear. 2) We have found two different behaviors depending on the type of a-clorocetona:-a-clorocetonas cyclical rigid (rings six or fewer links) leads in most cases to g-cloro-b- hydroxy acids. - A-clorocetones cyclical flexible (rings over six stages) lead to a mixture of b-epoxiácidos and g-lactones. 3) It has carried out a studio of estereoquímica, from which one can conclude that dianiones of carboxylic acids attack on the anti-chlorine atom, only if there is an impediment estérico for this approach will be seen without an attack. C) Study of the reactivity and generation dianión of acetic acid. 1) The generation of dianión of acetic acid has been carried out in two ways) from a number subestequiométrica of amiduro lytic of 1,3,3-trimetil-6-azabiciclo [3.2.1] octane, with conditions better results for compounds carbonílicos not enolizables b) from an amount estequiométrica of dietilamiduro Lithium conditions with better results for compounds carbonílicos enolizables. 2) has been studied adding dianión of acetic acid at different compounds carbonílicos obtained directly adducts with chromatographic purity and yield moderates. This reaction involves the approval of two-carbon compound carbonílico, with yields equal to or greater than those of more complex methods. D) study chiral induction in additions dianiones of carboxylic acid compounds carbonílicos. 1) The diastereoselectividad in adding dianión acid Phenylacetic to acetophenone primarily favors the diasteroisómero R *, S *. When electrófilo is benzaldehyde, diastereoselectividad is controlled to provide a majority of diastereomers using different bases. Using dietilamiduro lithium leads mostly diastereoisómero R *, R * while the amiduros bidentados lithium lead mostly diastereoisómero R *, S *. 2) There have been low results in the induction chiral with amiduros of the following bases: ephedrine, pirrolidina-2- methanol, 1-bencilamino-2-propanol. 3) has been carried out, summarize the pheromone sex sitofilato in two stages. The first step is the addition of dianión of propionic acid to propanal and second in a Fischer esterification with 2-pentanol product obtained in the first step. 4) All attempts to change the diastereoselectividad through different bases and additives have proved fruitless. 5) In a similar way to point 2, there have been low chiral induction results, which leads us to consider new types of chiral bases.

Author: Bernabé Zafón Virginia.
Year: 2006.
University: VALENCIA.
Place of defense: Facultad de Química.
Place of preparation: Facultad de Química.

Summary: First, we studied the resolution of mixtures of surfactants using capillary electrophoresis (CE) spectrophotometric detection. We developed a procedure that allowed separate, characterize and determine mixtures of alkyl ether sulfates and fatty acids in cleaning products. In addition, it was resolved mixtures of surfactants with alquilbenceno sulfonate earlier (ABS). To resolve mixtures were used experimental methods simple, but were also used tools quimiométricas alternatives. It has also developed the separation of families of other non-ionic surfactants and ambiiónicos with ABS, optimizing the experimental conditions and through procedures quimiométricos improved resolution and assured the allocation of the peaks to the families of surfactants. It worked with other non-ionic surfactant widely used in cleaning products that are ethoxylated fatty alcohols. We developed a study on the detection of these solutes in mass spectrometry (MS) without prior derivatization. We calculated response factors using direct infusion of oligomers in different ways, in the middle chosen as optimal established models for the prediction of response factors. It demonstrated the compatibility of the detection method with a technical after chromatographic separation or electroforética. The alcohols without etoxilar showed an extremely low sensitivity that prevented its calibration. To improve the sensitivity developed a quick and simple oxidation of alcohol to carboxylic acid group using chromic oxide. For fatty alcohols without etoxilar reaction was quantitative, but were obtained yields well below 100% for ethoxylated alcohols. This, coupled with the lack of standards acids etoxi-carboxílicos did not allow the use of this procedure for the quantification of ethoxylated alcohols. However, it demonstrated the usefulness of the method to quantify not ethoxylated fatty alcohols in cosmetics and personal hygiene. The alquilpolifosfonatos (APPs) are additives that are found in cleaning products. It is characterized by a rapid infusion of direct mass spectrometry. Impurities were detected whose molecular structures showed a lack of one or more groups phosphonate respect to the nominal compound. Using studies MSÂ ² explained satisfactorily all roads reaction observed. To ensure the presence of impurities developed a method of CE-MS. Finally, we developed a method of EC coupled with indirect photometric detection (IPD) to characterize quickly and easily the APPs. The resolution was also improved method CE-MS, allowing comparison of the electroferogramas of CE-IPD and CE-MS. Improving the resolution allowed to identify new impurities. The method CE-MS applied to the determination of APPs in cleaning products formulation complex.

Author: COLL BAU MARIONA.
Year: 2006.
University: AUTÓNOMA DE BARCELONA.
Place of defense: I.CIENCIA DE MATERIALES.
Place of preparation: INSTITUTO DE CIENCIA DE MATERIALES DE BARCELONA (ICMAB-CSIC).

Summary: Since the discovery of high-temperature superconductivity (HTS) in cuprate materials, substantial efforts have focused on developing a high-current superconducting wire technology to fully exploit their fundamental current-carrying capability. YBa2Cu3O7 (YBCO) is the most promising material for HTS wires (second-generation coated conductors) because it has a very high potential to carry high currents at high magnetic fields operated with liquid nitrogen cryogenics (65-77K). One crucial requirement for the preparation of YBCO coated conductors with high critical current densities is the elimination of weak links between YBCO grains. Weak links in the high temperature superconductors are produced by grain boundaries that lead to a weak coupling between the superconducting grains and consequently to a reduction in the critical current density. Thus, the key is to prepare a textured substrate adequately buffered with oxide layers which transmit, totally or partially, the underneath structure to the superconducting layer. Presently, there are two main techniques for textured template fabrication: Rolling Assisted Biaxially Textured Substrates (RABiTS) and Ion Beam Assisted Deposition (IBAD). Among the various process used to prepare YBCO and buffer layers films, metalorganic decomposition (MOD) has recently emerged as a very competitive approach to cost-effective manufacturing process that allow to easily control precursor chemistry maintaining high electrical performance in the superconducting layer. The aim of this Thesis, is to fabricate all-chemical YBCO multilayered system, using trifluoroacetates (TFA) precurors for YBCO, with high critical current density to be further transferred on metallic substrates. It requires a tight control of the interface quality in the multilayered architecture, i.e. between a substrate, one or several buffer layers and the superconducting layer itself. Although the film and the substrate have similar structure, the film can undergo a temperature-induced morphological instability due to the interfacial strain associated to the lattice parameter misfit. Simple analysis of surface free energy for YBCO films on different substrates have allowed to predict the equilibrium conditions to avoid dewetting of YBCO thin films. The optimum oxide buffer combination depends on the nature of the metallic substrate. In the present work the search for YBCO buffer layers has centered on SrTiO3 with perovskite and CeO2 with fluorite structure since they have been successfully used in the literature by vacuum techniques as the first approach to medium cost coated conductors. To obtain high quality TFA-YBCO films on those buffer layers it is required a good knowledge of the multilayer growth conditions of these oxides based on CSD, to optimize the underlying cap layer quality and to determine the parameters that influence the subsequent YBCO final texture and superconducting properties. This Thesis is divided into nine chapters. The properties of high temperature superconductors and especially of YBCO are reviewed in chapter 1, including an overview of the chemical solution deposition route and a brief summary of the TFA-YBCO process. In Chapter 2 the experimental techniques used for the structural, microstructural, morphological, chemical characterization of superconducting and buffer layers are presented. Superconducting and electrical resistivity measurements for YBCO films are also described. The experimental description with the different steps and parameters that are required for the preparation of YBCO films by trifluoroacetate route (TFA), as well as the preparation of SrTiO3, BaZrO3 and CeO2 buffer layers by metalorganic decomposition are described in Chapter 3. Chapter 4 contains the study of the spontaneous generation of strain-induced surface structures in TFA-YBCO films epitaxially grown on different types of single crystals (LaAlO3, SrTiO3 ) or oxide buffer layers with modified lattice mismatch values (BaZrO3). Chapter 5 describes the influence of perovskite mul 8 tibuffer 830 ed architecture quality (SrTiO3 and BaZrO3) on the epitaxial growth of TFA-YBCO film. In chapter 6 we analyse the influence of processing atmosphere on CeO2 film morphology, chemistry and texture when deposited by sputtering on YSZ single crystal. We have described the optimal CeO2 surface morphology for subsequent TFA-YBCO growth. Most favourable conditions are then applied to CeO2 deposited on YSZ/Ni and on YSZ/SS substrate. Finally buffer layer quality is correlated with YBCO critical current density. In chapter 7 we present a complete analysis of CeO2 and doped-CeO2 buffer layer fabricated by the MOD route on YSZ single crystal as a model system. Analysing morphology, texture, microstructure and chemistry of undoped and doped MOD-CeO2 films we have identified the optimal conditions to obtain highly textured CeO2 films. Results are discussed in terms of atomic mobility in MOD-CeO2 films. We establish a correlation between CeO2 properties (morphological, structural) and quality of TFA-YBCO film. PLD-YBCO film quality on MOD-CeO2 and doped-CeO2 films is described in chapter 8. We compare PLD-YBCO films with optimized TFA-YBCO films on doped-CeO2 films, analysing in particular the quality of cap layer and the role of interface reaction between YBCO and CeO2 on the final superconducting film quality. Furthermore we carry out an optimization of TFA-YBCO growth parameters. Finally in chapter 9 general conclusions are drawn.

Author: GONZÁLEZ GARCÍA NÚRIA.
Year: 2006.
University: AUTÓNOMA DE BARCELONA.
Place of defense: FACULTAT DE CIÈNCIES.
Place of preparation: UNIVERSITAT AUTÒNOMA DE BARCELONA.

Summary: This thesis focuses on the theoretical study of the processes involved in the oxidation of dimethyl sulfide in the troposphere, and the consequences that products are formed in this process can have on the atmosphere. The importance of this molecule lies in the fact that the main products of their oxidation (sulfuric acid and metanosulfónico) can be related to the processes of formation of clouds. It has been suggested that these acids can promote the formation of clouds in the troposphere, which would reduce solar radiation reaching the Earth, to the point where they contrarestar global warming of the planet. Given that dimethyl sulphide is the main sulfur compound of natural origin in the troposphere, we could be ahead of a process of self-regulation of the temperature of the planet. Thus, the study of chemical reactions that lead from dimethyl sulfide to the corresponding acids is highly interesting from the point of view of atmospheric chemistry. In addition, these reactions features also make them attractive from the point of view of theoretical chemistry.

Author: Montoya Garcia Vanessa.
Year: 2006.
University: AUTÓNOMA DE BARCELONA.
Place of defense: Facultat de Ciències.
Place of preparation: Facultat de Ciencies.

Summary: In this work we have synthesized new ligands N-alquil-3 ,5-pirazol from ligand 3,5-pirazólico and haloalcano appropriate toluene or THF using as a basis NaOEt or NaH. When the ligand precursor contains a replacement piridilo, alkylation reaction presents a great regioselectividad. Have been carried out theoretical calculations to rationalize these experimental facts, noting that this regioselectividad is due to the formation of a chelate between Na + and the ligand 3,5-piridilpirazol. It has explored the reactivity of several of these ligands with different products departure of palladium and platinum (II) was obtained in all cases with a complex geometry plano-cuadrada. In the reaction of the ligands pirazólicos monodentados with clorocomplejos of palladium (II) or platinum (II) complexes are obtained trans [MCl2 (L) 2]. The presence of one or two isomers in solution (syn or anti) is due to the impediment of rotation around the link Pd-N controlled by factors estéricos from the string length and nature of the metal. On the other band, the reaction between the ligands 3-5-piridilpirazol and clorocomplejos of Pd (II) and Pt (II) in a ratio 1:1 or 2:1 form complexes cis- [MCl2 (L)] or [ M (L) 2] (X) 2 (X = BF4 or BPh4) respectively. Once synthesized complexes cis- [PdCl2 (L)], it has tested its reactivity front ligands monodentados as trifenilfosfina and producing new pyridine complex by replacing the ligands chlorides by the corresponding ligand monodentado. It has also been tested the catalytic activity of the complex formula cis- [PdCl2 (L)] in the reaction Heck Finally, have been synthesized complexes alilpaladio [Pd (n3-C3H5) (L)] (BF4) with ligands 3.5-piridilpirazol from appropriate ligand and dímero [Pd (alilo) Cl] 2 in the presence of AgBF4. Pudiéndose evaluate processes fluxionales introducing the group alilo in solution

Author: Colera Llavata Manuel.
Year: 2006.
University: VALENCIA.
Place of defense: Facultat de Química.
Place of preparation: Facultat de Química.

Summary: Summaries of derivatives 18-corona-6 both enantioméricamente pure as derivatives of cyclohexane, for the study of complexation and extraction ammonium salts chiral. Summaries of quimiosensores derivatives ciclohexanos trans-transoide-trans-tetrasustituidos to study the recognition dicarboxilatos.

Author: CARRASCO PANCORBO ALEGRÍA.
Year: 2006.
University: GRANADA.
Place of defense: Facultad de Ciencias.
Place of preparation: FACULTAD DE CIENCIAS.

Summary: The dissertation can be divided into two distinct blocks. A first block (Introduction) collects information about the matrix studied (olive oil) and the techniques separativas and detection employed (EC and HPLC with UV detection and MS). The second, which encompasses the results and discussion can be divided into several sections: 1) Carrying out a review on analytical methodologies for the collection, separation and quantification of phenolic compounds in olive oil. 2) Study of the family of phenolic acids in olive oil virgen-extra. 3) Evaluation of antioxidant capacity of individual phenolic compounds in olive oil. 4) Design and implementation of a simple method electrophoretic able to characterize simple phenols, lignanos, complex phenols, flavonoids and phenolic acids so simultaneously in olive virgen-extra. 5) Assessment of the influence of the thermal oxidation in the composition phenolic

Author: Barro Piñeiro Ruth.
Year: 2006.
University: SANTIAGO DE COMPOSTELA.
Place of defense: Facultad de Química.
Place of preparation: Fac. Química e Instituto de Investigación y Análisis Alimentario, Univ. Santiago de Compostela.

Summary: In this paper, we have developed and optimized several analytical methods for the determination of organic pollutants in air. The methodological strategies are designed based on the sampling of pollutants in the air by solid phase extraction (SPE), followed by the extraction of the analytes retained in the adsorbent through microextracción in solid phase (SPME), or by applying ultrasonic with very small volumes of solvent. The combined procedure BDS and SPME avoids the use of organic solvents, or minimized to only a few microliters, while providing high enrichment factors, resulting from the concentration of analytes in a first adsorbent, and later in the microfase a fiber SPME. Additionally, we have developed strategies extractive based on the application of ultrasound, which reduce the addition of solvent to 1 mL or less. The gas chromatographic final determination is performed using different detector (ECD, micro-ECD, MS and MS in tandem). The proposed methodologies have been applied to several families of compounds, covering priority pollutants and emerging: chlorobenzenes, polychlorinated biphenyls and pyrethroids. They can be found as contaminants in internal or external environments, such as homes or workplaces. The selection and optimization variables influencing stages of sampling and concentration of analytes have allowed propose experimental conditions appropriate in each case. Have also been used different types of experimental designs to simultaneously optimize the factors considered most important in determining each type of compound, which is also allowed to study the possible effects of interaction between factors. The evaluation of the parameters indicators of the quality of an analytical approach, in terms of linearity, recovery, repeatability, reproducibility and sensitivity, have provided satisfactory results. In general, developed methods have been applied to actual air samples contaminated with the analytes. Among the advantages of a practical nature of the proposed methods is the fact that it has not been necessary pre-conditioning of the adsorbent used to retain the compounds of interest. Moreover, since only need 25 mg, reuse is not practical, thus avoiding additional stages of cleanup. The minimization of organic solvents, often toxic and expensive, offers a double advantage; on the one hand the procedure can be described as respectful of the environment and on the other, avoiding a concentration of the extracts later. The total analysis time is reduced to a maximum of 1 h / sample, but if carried out simultaneously chromatographic determination of analytes in a sample and the extraction of the following (since the times of both phases are similar) or it is possible the automation of the process, the times can be further reduced. As not require a complex instrumentation, these procedures are also suitable for non-specialized laboratories, which are able to carry out analysis of air from time to time. The proposed methods are sensitive enough to identify the compounds under study well below the legal limits and / or recommended by governmental institutions. Because of its simplicity, speed and low cost, are an interesting and attractive alternative to methods currently available.

Author: ANGLES MARQUEZ MIGUEL FRANCISCO.
Year: 2006.
University: POLITÉCNICA DE VALENCIA.
Place of defense: Universidad Politécnica de Valencia.
Place of preparation: Universidad Politécnica de Valencia.

Summary: In the UPV, and in the vast majority of institutions of higher education scientific and technical Spanish, the students used to finish his career a number of years much higher than the theoretical established, with high drop-out rates. The dropout and repetition rates are particularly high in the first courses, a situation which is often attributed mainly to the lack of concurrence between the end of high school (or Training) and the demands of a first year of college, and various shortcomings of the students: study habits, autonomy, etc.. With our work we wanted to reduce these dropout and repetition rates and ultimately contribute to improving learning and performance of students. This experience innovation has been done in a real classroom for three courses at the University course Fundamentals of Chemical Engineering at the College of Rural and Oenology (ETSMRE) of the Polytechnic University of Valencia. An important part of the evaluation has been carried out through the application Paris for this work has contributed to its purification, and validation first applications in a real context. Our approach to learning is based on the results of a diagnostic evaluation, to structure some initial activities to help overcome the deficiencies. By that diagnostic evaluation have been able to demonstrate the difference in level between students coming from high school and those from vocational modules. It has also been observed an increased rate of dropouts of the latter. All this suggests the need to reformulate the terms of access to engineering studies of the students from PF.

Author: GARCÍA GIMÉNEZ JOSÉ LUIS.
Year: 2006.
University: VALENCIA.
Place of defense: FACULTAT DE QUÍMICA.
Place of preparation: DEPARTAMENTE DE QUÍMICA INORGÁNICA. FACULTAT DE FARMÀCIA.

Summary: The overall objective of the research conducted in this PhD thesis has been obtaining complexes of Cu (II) to submit activity nucleasa, establish ways to interact with DNA and the mechanism of rupture of the double helix catalyzed by them. The ability to digest the DNA is of great interest in the field of medicine and biotechnology with the potential use of metal complexes as anti-tumor agents. First were synthesized and characterized sulfonamide N-sustituidas from adenine, 2-amino-4 ,5-dimetiltiazol and 2-picolilamina. These ligands have been developed various complexes of Cu (II) and mononuclear polynuclear which have been characterized structurally and espectroscópicamente. In particular, it highlights the magnetic properties of polynuclear complexes. With the complex characterized, has studied the ability and interacted with the new complexes with DNA using the technique of fluorescence spectroscopy, analysis of the melting temperature of DNA and measures such as mechanical viscosimetría. Where there is a different form of interaction of the complexes with nucleic acids (intercalation, interaction by the grooves or interaction of external sphere). It has been tested activity nucleasa the complex through the technique of in agarose gel electrophoresis. It has also been studied cinéticamente the degradation of how superenrrollada DNA to form circular. It has studied the activity nucleasa the complex in the presence of various inhibitors agents to establish the reactive oxygen species involved in the cleavage of the double helix. The results show high activity nucleasa the complex and species involved in the degradation of DNA. It has posed a reaction mechanism.

Author: Galet Domingo Ana Guadalupe.
Year: 2006.
University: VALENCIA.
Place of defense: Facultat de Química.
Place of preparation: Facultad de Química - Institut de Ciència Molecular.

Summary: The compounds with transition from spin states are switchable between two competing thermodynamics: the state of high-spin (HS) and the status of low spin (LS). Both states differ in their magnetic properties, optical and structural. The change of status can be stimulated by a change in temperature, pressure or irradiation with light. This work is devoted to the synthesis and characterization of new compounds with transition from spin iron (II) polymeric and explore new fenomenologías. We have chosen as model compounds called chlathrates Hofmann developed by Iwamoto et al. Since the 70's. This thesis is organized into two parts. The first part provides an overview of spin on transitions, background and current situation, conceptual definitions, relevance and general interest. The second part begins with the study of the compounds heterobimetálicos derived from the metal ion coordination of Fe (II), the organic ligand pyrimidine and cyanides metal [M (CN) 2] - where M = Cu (I), Ag ( I) and Au (I). In these systems has been carried out structural characterization, and the study of the transition from spin-induced temperature, light and pressure, producing a wide variety of magnetic behavior. To conduct this study has been used techniques such as X-ray diffraction on monocristal with and without laser irradiation temperature variable X-ray diffraction powder, measures magnetism, fotomagnetismo and magnetism at elevated pressures all of them to varying temperature , calorimetry, absorption uv-visible, thermogravimetric analysis. The second chapter presents the results of the study of the system (Fe (pc) [Pt (CN) 4) Â nH2O which include the study of the effect of hydration of the sample on the behavior magnetic induction of a change in spin at room temperature by irradiation with a pulsed laser and the effect of substitution isomorfa system (FexM1-x (pc) [Pt (CN) 4) where M = Ni (II) and Co (II). For this second chapter has been used, in addition to the above characterization techniques, as other vibrational spectroscopy, Raman spectroscopy, spectroscopy MÃ ¶ ssbauerâ |

Author: Saurí Peris María del Carmen.
Year: 2006.
University: VALENCIA.
Place of defense: Facultad de Química.
Place of preparation: Departamento de Química Analítica, Facultad de Químicas, Universidad de Valencia.

Summary: The thesis presents a set of new methods aimed at identifying via electrochemical species pigmentantes in micro and nanomuestras from artistic and archaeological objects. It uses the general methodology of the voltammetry of microparticulas based on the transfer mechanics solid samples on the superificie electrode inert polymer film, compósitos grafito.polímero acrylic and graphite impregnated with paraffin in a vacuum. The methods developed are applicable to the identification and speciation species pigmentantes both inorganic, organic samples mural painting and easel, polychromed wood, ceramics and fiber pieces, including pigments of the family lands iron antraquinónicos, flavonoids and allied, among others.

Author: Bermúdez Saldaña José María.
Year: 2006.
University: VALENCIA.
Place of defense: Facultat de Química.
Place of preparation: Facultat de Química.

Summary: The objective of this thesis is the development of systems based on electrophoretic and chromatographic media micelares to describe and predict the ecotoxicity of various environmental pollutants. Specifically worked on three interrelated; obtaining accurate retention parameters, the development of quantitative retention-activity relationships (QRAR) parameters for ecotoxicological as acute toxicity (pLC50) and bioconcentration factor (logBCF) on fish and the coefficient adsorption in soils (logKOC), and the development of quantitative structure-activity relationships (QSARs) for the acute toxicity of pesticides in fish inhibitors of the enzyme acetylcholinesterase. In the first part of this thesis, proposed new expressions for estimating the retention factors (k) of analytes in liquid chromatography, based on the use of one or two reference substances. These new proposals supersede measures chromatographic parameters; time extra-columna and basic Total time (usually associated with high precision) and the expressions used by more conventional, far more precise times for a total of retention / two chemicals reference. Working conditions intermediate precision, the new proposals (especially based on two reference substances) estimates k generate more accurate and consistent long-term. In the second part, were developed models QRAR based on chromatography micelar of bio-reparto (BMC), which uses phases of the type C18 and stationary phases mobile micelares of surfactant Brij35. Our results indicate that: - The use of parameter retention logk for 85 pesticides, obtained for different concentrations of Brij35 allowed to discriminate against its toxic mechanism of action (MOA). For non-polar narcotics obtained a model toxicidad-retención more reliable than those based on the ratio of n-octanol - agua division, logP. - Use of values logk obtained at different pH values (6, 7 and 8) for a set of 19 phenols allowed ranked phenols MODE-1 and MODO-2. This classification proved to be more useful than that based on the MOA for the development of models (Q) RAR to describe and predict the toxicity depending on the pH (range 6-8) in the aquatic environment. There was a model QRAR for phenols MODE-1 and RAR for MODO-2. - For 85 pesticides that yielded a model QRAR to estimate the logBCF of the most persistent in the environment (logBCF> 2). Since the value of logk = 1.85 were classified correctly all pesticides R-53 (hazardous substances in the long term) by replacing the use of two parameters (logP and logBCF; recommended by the European Union). Using the values of logk in BMC provides similar results to other methodologies. While the BMC gets properly modeling some chemicals anomalous in the CN system and presents a greater availability and lifetime that the columns filled with natural soil. - The values of logk of 24 aromatics highly hydrophobic obtained by chromatography electrocinética micelar (MEKC) with 4 bile salt were different useful to describe and predict various parameters ecotoxic (LC50, EC50, IC50, ChV, logBCF and logKOC) on fish, Daphnia and green algae. In the third and final part of this thesis, QSAR methodology is used to describe and predict the acute toxicity in fish from 75 pesticides oxono- and tiono-organofosforados (POs) and carbamates whose response tóx 8 ica is l 56c as a result of inhibition of the enzyme acetylcholinesterase. To model the toxicity using multivariate methods such as multiple linear regression (MLR) or partial least squares regression (PLS). QSAR models for all pesticides (general models) and those obtained after separate them into chemical classes were limited applicability descriptive and predictive. After separating pesticides by the MOA; narcotics no-polares and 'real' AChE inhibitors, obtained QSAR models were suitable, especially based on parameters related to hydrophobicity, hydrogen bridges, metabolic activation of tiono-OP and interactions with aromatic residues.

Author: Moros Portolés Javier.
Year: 2006.
University: VALENCIA.
Place of defense: Facultat de Química.
Place of preparation: Facultad de Química.

Summary: In this thesis integrates a set of work on the implementation of some of the different treatments numerical those who may be submitted analytical data obtained using different techniques for measuring the vibrational spectroscopy, looking well empower and enhance the performance of different developed analytical processes, ensuring a better quality of the results obtained. Thus, in the hope of being able to show the wide range of possibilities it offers, not just the vibrational spectroscopy, but the implementation of the Quimiometría on instrumental data obtained through this, we selected a number of samples varied nature in terms of composition, status and concentration levels of analytes of interest, along with a highly extended, and encompassing pharmaceuticals, food products (juices, shakes, yogurt, chocolate, vinegar), commercial formulations of pesticides or chips leather used for the treatment of polluted water. Specifically, the work embodied in this Doctoral Thesis intended to be a useful guide in which it reveals the evolution from analytical methodologies that require a certain chemical treatment of the sample to get some selectivity and therefore require a minor mathematical treatment the data, methodologies to those that require little or no chemical treatment prior to the samples but, as a result, they need a numerical treatment more relevant and complex data instrumentals. But it is possible to evaluate the benefits of Quimiometría combined with infrared vibrational spectroscopy to the development of analytical methodologies that can be considered as a serious alternative for laboratories that develop and optimize analytical methods for quality control of products. For different studies have used different modes of action (Transmittance, Reflectance Total Atenuada or Diffuse Reflectance) both in the region averaged spectrum infrared (MIR) and in the region near-infrared (NIR). So, can be found on one side those methods of analysis based on the use of calibration univariate (zero-order) to link the analytical signal recorded (or derivative) with the property that was intended to quantify. These simple procedures have been applied to the determination of pesticides and active ingredients in pesticides and pharmaceuticals, respectively. On the other side are those methods in which the problem was solved by using a series of mathematical algorithms, in order to try to predict the property of interest from non-selective responses instrumental. Within this group of works have been used different techniques for multivariate calibration results, both for qualifying and for the determination of the properties and the parameters of interest. Here, we have made use of the Principal Component Analysis (PCA), in the Partial Least Squares Regression (PLSR), as well as Artificial Neural Networks (ANN), selecting for each of the studies the most appropriate method that allowed to ensure the highest quality of the results obtained through a maximum predictive ability. Finally, it has developed a methodology based on information generation of second order from the combination of multiconmutación and vibrational spectroscopy for determining the degree of acidity in samples of vinegar, using the method PARAFAC for data processing vibrational generated. The results obtained through the implementation of the various models developed have proved to be of adequate quality, so that the methodologies proposed 8 s, after 377 be validated through the identification of the corresponding analytical characteristics, are appropriate to carry out a proper quality control of the various products in this Doctoral Thesis.

Author: Ventura Gayete Josep Francesc.
Year: 2006.
University: VALENCIA.
Place of defense: Facultat de Química.
Place of preparation: Facultad de Química.

Summary: In this Doctoral Thesis has aimed to take an approach to environmental sustainability in the quantitative analysis of vibrational spectroscopy. To this end, four have been the backbones that have been considered: i) the search for alternatives to chlorinated solvents commonly used, or where it has not been possible, reducing the amount spent on them, ii) the automation of the analysis , choosing the use of multiconmutación iii) using extraction techniques such as pressurized solvent extraction, combined with vibrational spectroscopy, and iv) the comprehensive treatment of the samples mount in flux. In this regard have developed a number of applications designed to be used as a technique for routine quality control. The results obtained in the 7 tasks included in the report thesis show the potential of vibrational spectroscopy by Fourier transform in the field of sample analysis of a very different nature. We have implemented several strategies to ensure the development of environmentally sustainable analytical methods applied to various types of analytes and matrices: On the one hand, the technique of attenuated total reflectance in the middle infrared (ATR-FTIR) allows direct analysis of samples absorb strongly, as is the case with water. The use of cell accessories with ATR crystal diamond has proved extremely useful because of the hardness and chemical resistance of this material. The possibility of obtaining the spectrum of virtually any liquid or solid substance, regardless of their chemical reactivity, makes it a particularly interesting technique and reducing to a minimum sample handling and eliminating the use of harmful solvents. Moreover, it has been implemented multiconmutación coupled with infrared techniques to solve various problems analytical. The practical aspects of the multiconmutación that has been shown here, can be summed up in the versatility of strategy analysis, the reduction in sample handling, ease of design, the possibility of simple automation and miniaturization of systems. Regarding the versatility, we have three strategies to raise the multiconmutación differently: one of them has as its main function to reduce the handling of samples and patterns in the action, undertaken in a way flow stopped in the other two draws the ability of the multiconmutación to make dilution of the sample and adding a standard online; All these are examples of multiple variety of approaches which allows multiconmutación to when planning an experimental design to the appropriate analytical problem raised. Referring to the sample handling, systems with multiconmutación allow a minimal intervention of the analyst: this represents an increase of comfort and, therefore, involves improving the efficiency of an analytical laboratory, regardless of the increase in the frequency analysis is achieved through the method itself. Moreover, experience in application development has shown that with some minimal knowledge of programming and electronics can design and build systems capable of performing almost any typical process of a method of analysis, especially when it comes to phase measurement. This advantage, perhaps not sufficiently exploited so far, particularly in the case of vibrational spectroscopy suggests a huge amount of applications almost immediate, which could be extremely useful in analyzing field and routine. Also techniques have been applied pretreatment of the sample, such as the pressurized solvent extraction, which can reduce the consumption of harmful solvents and improve the frequency of analysis, or in solid phase extraction as a strategy for overcoming 8 the limit 598 ation the low sensitivity of the FTIR spectrometry through the preconcentration of the analytes and their elution online, with applications in the environmental samples. Finally, it has conducted comprehensive treatment of the sample with selective extraction of the analyte in line with the aim of reducing both the handling of the sample as the solvent consumption, developing a method of analysis applicable to the quality control, which continues to sustainability criteria in terms of consumption of harmful solvents and is easily automatable. In short, it has demonstrated the great capacity of the techniques FTIR and FTNIR to solve problems common analytical and the critical role that must be present in the analytical laboratories.

Author: Rimola Gibert Albert.
Year: 2006.
University: AUTÓNOMA DE BARCELONA.
Place of defense: Universidad Autónoma de Barcelona.
Place of preparation: Universidad Autónoma de Barcelona.

Summary: One molecule is activated when action by an external agent shows a different reactivity in its normal state. Frequent activation modes are the interaction of metal cations, the absorption of ionizing radiation or ultraviolet, or adsorption on solid surfaces. This paper deals with the activation of small biomolecules, in particular amino acids and peptides, for interaction with copper cations and aluminosilicates. Today we can generate systems metal-ligando in gas phase and study their reactivity induced by the interaction with metal cations through the techniques of mass spectrometry. This thesis therefore focuses on the context of chemistry metaloiónica in gas phase where they combine theoretical calculations with mass spectrometry experiments. In addition, traffic from a mecanocuántico activation of biomolecules by the interaction with surface minerals, in particular the formation of liaison peptídico between two amino acids interacting with aluminosilicates, given its relevance in the context of prebiotic chemistry.

Author: RODRIGUEZ SAN SEGUNDO HUGO JOSE.
Year: 2006.
University: POLITÉCNICA DE MADRID.
Place of defense: E.T.S. DE INGE. DE TELECOMUNICACION.
Place of preparation: INSTITUTO DE ENERGIA SOLAR ESCUELA TECNICA SUPERIOR DE INGENIEROS DE TELECOMUNICACION.

Summary: In this thesis has been designed, built, characterized and tested a prototype reactor epitaxial high production capacity for the subsequent manufacture of solar cells. The high capacity is achieved by susceptores densely stacked, vertical and parallel to each other, which is directly heated by Joule effect. The gas flows vertically between them, and the deposit is held in metallurgical refining silicon wafers, low-cost, which are placed on susceptores. The gas must be recirculated for the most part, which involves theoretical studies of the chemical transformations that take place during the cooling in recirculation, and how these affect the growth. A mathematical model based on the limitation by using mass transport equations for the conservation of total mass, mass gas source, and energy. By this model has obtained an optimum geometry of the system and an environment favorable to growth, which also favor it over other competing reactions. Construction and characterization of the prototype found that most of the teams working properly. Specifically, the effect Joule get homogeneidades temperature acceptable around the block susceptores. On the other hand, some design flaws emerged at this stage, as the rigidity of electrical contacts, or loss of reflectivad of reflective screens. The first problem was resolved satisfactorily with electrical contacts flexible. The second still remains unresolved. The first growths, which have taken place after the characterization, have already demonstrated the enormous potential of the reactor concept: it has succeeded epitaxia in 50 wafers at the same time, with dispersal means including thickness less than 8%.

Author: Herbello Hermelo Paloma.
Year: 2006.
University: SANTIAGO DE COMPOSTELA.
Place of defense: Facultad de Farmacia.
Place of preparation: Facultad de Química.

Summary: This work aims to be a small contribution to the study of trace metals in seawater in order to assess their impact on the environment as there is little information about the content of trace metals in seawater. This deficiency is due to the complexity of this matrix and low levels of concentration in those metals. The difference in toxicity among different species and inorganic Cr As has been the approach taken in the choice of the elements under consideration. On the one hand it has been proposed a method for the determination of Cr (VI) by ETAAS. The separation of Cr (III) is possible given the high volatility of chelate forming selectively with 1,1,1-trifluoro-2 ,4-pentadiona (TFA). And on the other hand has developed a method for the preconcentration and separation of As (III) and Cr (VI) in seawater, by withholding knotted in a reactor of the complex formed with ammonium pirrolidinditiocarbamato, APDC. It has used a technique of flow injection coupled with a team of Atomic Absorption Spectroscopy with Atomización Electrotérmica, FI-ETAAS. Finally, these methods have been applied to study the distribution of these metals in the Ria de Arousa.