Introdução: Reportam-se modificações metabólicas e hemodinâmicas em pacientes críticos em sepse e incluem-se neste grupo, os grandes queimados. Nesses pacientes ocorrem profundas alterações na farmacocinética de agentes antimicrobianos hidrofílicos prescritos no tratamento empírico das infecções bacterianas graves. Então, o alvo terapêutico não é alcançado em decorrência das concentrações plasmáticas desses antimicrobianos serem inferiores às requeridas para o controle das infecções. Na suspeita de sepse, a terapia antimicrobiana de primeira escolha prevê administração sistêmica dos antimicrobianos a vancomicina e a piperacilina, sendo esta última associada à tazobactana, um inibidor da beta-lactamase. Objetivo: Propôs-se nesse projeto a investigação da farmacocinética da vancomicina e da piperacilina através do monitoramento plasmático. Propôs-se ainda a avaliação da efetividade dos dois antimicrobianos na dose empírica recomendada com base na função renal aos pacientes críticos grandes queimados em sepse por patógeno hospitalar. Métodos: Investigaram-se 42 pacientes grandes queimados em terapia intensiva com lesões de 2° grau profundo e de 3° grau com suspeita de sepse por patógeno hospitalar. A prescrição constou de terapia combinada de vancomicina e piperacilina nas doses empíricas recomendadas com base na função renal de cada paciente. Seguem as características dos pacientes investigados: adultos de ambos os sexos (33M/9F), médias/ DP: 40,9±17,5 anos, 70,1±11,5 Kg, 33,6±20,7% de superfície corpórea total queimada (SCTQ), sendo 37/42 pacientes apresentaram função renal normal, e 5/42 pacientes com insuficiência renal, sem necessidade de prescrição de diálise pelo nefrologista. Registrou-se trauma térmico/ elétrico em 39/3; a lesão inalatória ocorreu em 25 pacientes. Efetuou-se coleta seriada de 2-3 amostras sanguíneas (Vacutainer/EDTA sódico); após separação do sangue por centrifugação a 2800g para obtenção do plasma, realizou-se o processamento laboratorial para os dois analitos pelo monitoramento plasmático da vancomicina e da piperacilina através da cromatografia líquida de alta eficiência. Realizou-se o estudo farmacocinético com base no modelo aberto monocompartimental. Através da análise PK/PD foi possível determinar os índices de efetividade para a vancomicina a partir da razão da área sob a curva no intervalo de 24 horas e a concentração inibitória mínima ASCss 0-24/CIM > 400, e para a piperacilina 70%fΔT>CIM; o significado desse último índice determinado para o derivado β-lactâmico está relacionado a fração do intervalo de dose em que a concentração plasmática livre da piperacilina permanece acima da CIM. Resultados: Registrou-se alteração da farmacocinética da vancomicina e da piperacilina nos pacientes queimados com função renal normal pela comparação entre cada paciente e o valor de referência reportado para voluntários sadios. Nos pacientes com insuficiência renal registrou-se o prolongamento da meia vida biológica pela alteração na depuração e/ou no volume de distribuição. Registrou-se farmacocinética alterada em diferentes proporções tanto nos pacientes queimados com função renal preservada, como naqueles com disfunção renal. Após a análise PK/PD, a dose empírica de vancomicina administrada aos pacientes com função renal normal, registrou-se cobertura em 37/37 pacientes contra patógenos sensíveis (CIM 1mg/L), caindo para 18/37 (49%) pacientes para patógenos, CIM 2 mg/L. Não se registrou cobertura contra patógenos CIM>2 mg/L (CIM 4mg/L) independente da função renal dos pacientes. Após a dose empírica prescrita na função renal preservada, a cobertura da piperacilina ocorreu até CIM 4mg/L, para os patógenos sensíveis, caindo para 34/37 (92%) CIM 8 mg/L. Apenas 22/37 (60%) pacientes se encontraram protegidos contra patógenos sensíveis mais agressivos CIM 16 mg/L Pseudomonas aeruginosa e Enterococcus spp. Conclusão: O monitoramento plasmático da vancomicina e da piperacilina indica que a dose empírica recomendada para os dois agentes não alcança efetividade no controle das infecções causadas por patógenos hospitalares sensíveis à vancomicina (CIM>1mg/L) e à piperacilina (CIM >4 mg/L) em consequência de níveis plasmáticos inferiores aos requeridos no controle das infecções, devido a profundas alterações na farmacocinética desses antimicrobianos. / Introduction: Metabolic and hemodynamic changes were reported in critically ill patients including burn patients in sepsis. Then, pharmacokinetics is altered in those patients mainly for hydrophilic antimicrobial agents prescribed for the control of severe bacterial infections; consequently, the therapeutic target wasn\'t reached based on drug plasma concentrations lower than expected. Antimicrobial therapy recommended in sepsis suspicious is based in a combination of two antimicrobials; vancomycin, a glycopeptides derivative and a beta-lactam agent piperacillin-tazobactam, a beta-lactamase inhibitor. Objective: It was proposed a pharmacokinetic investigation for vancomycin and piperacillin based on drug plasma monitoring followed by drug effectiveness measurements by PK/PD analysis after the empiric dose regimen recommended to normal renal function or renal failure burn patients in sepsis. Methods: 42 adult burn patients of both gender (33M/9F) with deep 2nd and 3rd injuries in septic shock by nosocomial pathogens under intensive care were investigated. A combined antimicrobial therapy at the recommended empirical dose regimen vancomycin-piperacillin was prescribed on the basis of renal function. Characteristics of population of patients investigated, means/SD were: 40.9±17.5 yrs, 70.1±11.5 kg, 33.6±20.7% total burn surface area (TBSA). Normal renal function was registered in 37/42 patients against 5/42 of them with renal failure. Thermal/electrical injuries occur in 39/3, and inhalation injury were in 25 of them. A serial of 2-3 blood samples were obtained from venous catheter into vacuum tubes (sodium EDTA); after centrifugation (2800g) plasma samples were obtained for drug plasma monitoring; both analytes, vancomycin and piperacillin were quantified by high performance liquid chromatography. Pharmacokinetics investigation based on one compartment open model was performed. PK/PD analysis was done to determine antimicrobial effectiveness against nosocomial pathogens isolated. Recommended drug effectiveness index was AUCss 0-24/MIC > 400 for vancomycin and 70%fΔT>MIC for piperacillin. Results: Pharmacokinetics for both antimicrobials investigated showed to be altered in a different extension for vancomycin and piperacillin in burn patients with normal renal function by comparison with reference data reported in healthy adult volunteers. PK/PD analysis indicated that after the initial dose regimen 2g daily for patients with normal renal function, the vancomycin effectiveness occurs only for susceptible pathogens MIC 1mg/L, once drug effectiveness falls to 49% (18/37) against pathogens (MIC 2mg/L). Similarly, piperacillin effectiveness occurs just for susceptible pathogens MIC ≤ 4 mg/L in patients with normal renal function, once only 22/37 (60%) of patients reached the target MIC 16mg/L for Pseudomonas aeruginosa and Enterococcus spp. Conclusion: Vancomycin and piperacillin plasma monitoring indicated that the therapeutic target wasn´t reached with the empiric dose regimen recommended against nosocomial pathogens vancomycin susceptible (MIC>1mg/L) and piperacillin susceptible (MIC >4 mg/L) due to plasma levels lower than expected as a consequence of kinetic disposition altered for both antimicrobials.

Introdução: Reportam-se modificações metabólicas e hemodinâmicas em pacientes críticos em sepse e incluem-se neste grupo, os grandes queimados. Nesses pacientes ocorrem profundas alterações na farmacocinética de agentes antimicrobianos hidrofílicos prescritos no tratamento empírico das infecções bacterianas graves. Então, o alvo terapêutico não é alcançado em decorrência das concentrações plasmáticas desses antimicrobianos serem inferiores às requeridas para o controle das infecções. Na suspeita de sepse, a terapia antimicrobiana de primeira escolha prevê administração sistêmica dos antimicrobianos a vancomicina e a piperacilina, sendo esta última associada à tazobactana, um inibidor da beta-lactamase. Objetivo: Propôs-se nesse projeto a investigação da farmacocinética da vancomicina e da piperacilina através do monitoramento plasmático. Propôs-se ainda a avaliação da efetividade dos dois antimicrobianos na dose empírica recomendada com base na função renal aos pacientes críticos grandes queimados em sepse por patógeno hospitalar. Métodos: Investigaram-se 42 pacientes grandes queimados em terapia intensiva com lesões de 2° grau profundo e de 3° grau com suspeita de sepse por patógeno hospitalar. A prescrição constou de terapia combinada de vancomicina e piperacilina nas doses empíricas recomendadas com base na função renal de cada paciente. Seguem as características dos pacientes investigados: adultos de ambos os sexos (33M/9F), médias/ DP: 40,9±17,5 anos, 70,1±11,5 Kg, 33,6±20,7% de superfície corpórea total queimada (SCTQ), sendo 37/42 pacientes apresentaram função renal normal, e 5/42 pacientes com insuficiência renal, sem necessidade de prescrição de diálise pelo nefrologista. Registrou-se trauma térmico/ elétrico em 39/3; a lesão inalatória ocorreu em 25 pacientes. Efetuou-se coleta seriada de 2-3 amostras sanguíneas (Vacutainer/EDTA sódico); após separação do sangue por centrifugação a 2800g para obtenção do plasma, realizou-se o processamento laboratorial para os dois analitos pelo monitoramento plasmático da vancomicina e da piperacilina através da cromatografia líquida de alta eficiência. Realizou-se o estudo farmacocinético com base no modelo aberto monocompartimental. Através da análise PK/PD foi possível determinar os índices de efetividade para a vancomicina a partir da razão da área sob a curva no intervalo de 24 horas e a concentração inibitória mínima ASCss 0-24/CIM > 400, e para a piperacilina 70%fΔT>CIM; o significado desse último índice determinado para o derivado β-lactâmico está relacionado a fração do intervalo de dose em que a concentração plasmática livre da piperacilina permanece acima da CIM. Resultados: Registrou-se alteração da farmacocinética da vancomicina e da piperacilina nos pacientes queimados com função renal normal pela comparação entre cada paciente e o valor de referência reportado para voluntários sadios. Nos pacientes com insuficiência renal registrou-se o prolongamento da meia vida biológica pela alteração na depuração e/ou no volume de distribuição. Registrou-se farmacocinética alterada em diferentes proporções tanto nos pacientes queimados com função renal preservada, como naqueles com disfunção renal. Após a análise PK/PD, a dose empírica de vancomicina administrada aos pacientes com função renal normal, registrou-se cobertura em 37/37 pacientes contra patógenos sensíveis (CIM 1mg/L), caindo para 18/37 (49%) pacientes para patógenos, CIM 2 mg/L. Não se registrou cobertura contra patógenos CIM>2 mg/L (CIM 4mg/L) independente da função renal dos pacientes. Após a dose empírica prescrita na função renal preservada, a cobertura da piperacilina ocorreu até CIM 4mg/L, para os patógenos sensíveis, caindo para 34/37 (92%) CIM 8 mg/L. Apenas 22/37 (60%) pacientes se encontraram protegidos contra patógenos sensíveis mais agressivos CIM 16 mg/L Pseudomonas aeruginosa e Enterococcus spp. Conclusão: O monitoramento plasmático da vancomicina e da piperacilina indica que a dose empírica recomendada para os dois agentes não alcança efetividade no controle das infecções causadas por patógenos hospitalares sensíveis à vancomicina (CIM>1mg/L) e à piperacilina (CIM >4 mg/L) em consequência de níveis plasmáticos inferiores aos requeridos no controle das infecções, devido a profundas alterações na farmacocinética desses antimicrobianos. / Introduction: Metabolic and hemodynamic changes were reported in critically ill patients including burn patients in sepsis. Then, pharmacokinetics is altered in those patients mainly for hydrophilic antimicrobial agents prescribed for the control of severe bacterial infections; consequently, the therapeutic target wasn\'t reached based on drug plasma concentrations lower than expected. Antimicrobial therapy recommended in sepsis suspicious is based in a combination of two antimicrobials; vancomycin, a glycopeptides derivative and a beta-lactam agent piperacillin-tazobactam, a beta-lactamase inhibitor. Objective: It was proposed a pharmacokinetic investigation for vancomycin and piperacillin based on drug plasma monitoring followed by drug effectiveness measurements by PK/PD analysis after the empiric dose regimen recommended to normal renal function or renal failure burn patients in sepsis. Methods: 42 adult burn patients of both gender (33M/9F) with deep 2nd and 3rd injuries in septic shock by nosocomial pathogens under intensive care were investigated. A combined antimicrobial therapy at the recommended empirical dose regimen vancomycin-piperacillin was prescribed on the basis of renal function. Characteristics of population of patients investigated, means/SD were: 40.9±17.5 yrs, 70.1±11.5 kg, 33.6±20.7% total burn surface area (TBSA). Normal renal function was registered in 37/42 patients against 5/42 of them with renal failure. Thermal/electrical injuries occur in 39/3, and inhalation injury were in 25 of them. A serial of 2-3 blood samples were obtained from venous catheter into vacuum tubes (sodium EDTA); after centrifugation (2800g) plasma samples were obtained for drug plasma monitoring; both analytes, vancomycin and piperacillin were quantified by high performance liquid chromatography. Pharmacokinetics investigation based on one compartment open model was performed. PK/PD analysis was done to determine antimicrobial effectiveness against nosocomial pathogens isolated. Recommended drug effectiveness index was AUCss 0-24/MIC > 400 for vancomycin and 70%fΔT>MIC for piperacillin. Results: Pharmacokinetics for both antimicrobials investigated showed to be altered in a different extension for vancomycin and piperacillin in burn patients with normal renal function by comparison with reference data reported in healthy adult volunteers. PK/PD analysis indicated that after the initial dose regimen 2g daily for patients with normal renal function, the vancomycin effectiveness occurs only for susceptible pathogens MIC 1mg/L, once drug effectiveness falls to 49% (18/37) against pathogens (MIC 2mg/L). Similarly, piperacillin effectiveness occurs just for susceptible pathogens MIC ≤ 4 mg/L in patients with normal renal function, once only 22/37 (60%) of patients reached the target MIC 16mg/L for Pseudomonas aeruginosa and Enterococcus spp. Conclusion: Vancomycin and piperacillin plasma monitoring indicated that the therapeutic target wasn´t reached with the empiric dose regimen recommended against nosocomial pathogens vancomycin susceptible (MIC>1mg/L) and piperacillin susceptible (MIC >4 mg/L) due to plasma levels lower than expected as a consequence of kinetic disposition altered for both antimicrobials.

Ce mémoire est consacré à la synthèse et à l'étude de complexes métalliques originaux contenant des carbènes N-hétérocycliques (NHCs) fortement encombrés. Trois familles ont été élaborées : 1) des complexes Pd-PEPPSI "dissymmétriques" comportant un ligand imidazolylidène (Im) ayant comme N-substituants un groupe 9-alkyl-9-fluorényle (AF) ainsi qu'un aryle. Ces complexes se sont avérés des catalyseurs remarquables en couplage de Suzuki-Miyaura, présentant des performances comparables à celles d'analogues porteurs de deux groupes AF (dont l'excellente efficacité avait déjà été établie), démontrant ainsi le fort rôle stabilisateur du groupe AF; 2) des complexes trigonaux de cuivre(I) de formule générale [Cu(Im)(2,2'-dipyridylamine)]BF4 où le ligand carbénique est soit un carbène symétrique de type AF2-Im, soit dissymétrique de type (AF,Ar)-Im. Ici encore, la présence de substituants AF est un élément favorisant la stabilité des complexes en solution par rapport à une décomposition photo-induite. Contrairement à son anaolgue ayant un imidazolylidène porteur de deux substituants EtF, le complexe [Cu((EtF,Ph)-Im)(2,2'-dipyridylamine)]BF4 présente la particularité d'être luminescent en solution et à l'état solide; 3) des complexes Pd-PEPPSI contenant un imidazolilydène N-substitué par deux groupes identiques dont les extrémités sont des récépteurs potentiels de type calix[4]arène. Ces complexes ont la propriété de s'auto-assembler en formant une entité où les centres métalliques sont stériquement très protégés, avec pour conséquence de modifier sensiblement les propriétés catalytiques attendues du complexe. / Described herein are the stepwise syntheses and properties of three types of complexes based on sterically encumbered N-heterocyclic carbenes (NHCs): 1) Pd-PEPPSI complexes with an unsymmetrical imidalolylidene ligand having its N atoms substituted by a bulky 9-alkyl-9-fluorenyl (AF) group and an aryl group. These turned out to be very active Suzuki-Miyaura cross coupling catalysts with an activity comparable to previously reported, highly performing "symmetrical" analogues which bear two identical AF substituents. These findings illustrate the high stabilising effect of each individual AF group; 2) Trigonal copper(I) complexes with the general formula [Cu(Im)(2,2'-dipyridylamine)]BF4 in which the NHC ligands are symmetrical or not. Here again the AF substituents ensure complex stability with respect to air when compared to analogues displaying sterically non-bulky substituents. One of the complexes, namely [Cu((EtF,Ph)-Im)(2,2'-dipyridylamine)]BF4, was found to be strongly luminescent in solution and in the solid state; 3) Pd-PEPPSI complexes in which calix[4]arene-substituted phenyl moieties have been grafted on both N atoms, these behaving as potential receptor units. Owing to the presence of the calixarene termini, complexes of this type were found to self-assemble, thereby resulting in dimers with sterically highly protected metal centres. The formation of such species was correlated to the catalytic performance of these complexes.

ABSTRACT HYDROGEN STORAGE IN MAGNESIUM BASED THIN FILMS Akyildiz, Hasan Ph.D., Department of Metallurgical and Materials Engineering Supervisor : Prof. Dr. Tayfur &Ouml / zt&uuml / rk Co-Supervisor : Prof. Dr. Macit &Ouml / zenbas October 2010, 146 pages A study was carried out for the production of Mg-based thin films which can absorb and desorb hydrogen near ambient conditions, with fast kinetics. For this purpose, two deposition units were constructed / one high vacuum (HV) and the other ultra high vacuum (UHV) deposition system. The HV system was based on a pyrex bell jar and had two independent evaporation sources. The unit was used to deposit films of Mg, Mg capped with Pd and Au-Pd as well as Mg-Cu both in co-deposited and multilayered form within a thickness range of 0.4 to 1.5 &mu / m. The films were crystalline with columnar grains having some degree of preferred orientation. In terms of hydrogen storage properties, Mg/Pd system yielded the most favorable results. These films could desorb hydrogen at temperatures not greater than 473 K. The study on crystalline thin films has further shown that there is a narrow temperature window for useful hydrogenation of thin films, the upper limit of which is determined by the intermetallic formation. The UHV deposition system had four independent evaporation sources and incorporated substrate cooling by circulating cooled nitrogen gas through the substrate holder. Thin films of Mg-Cu were produced in this unit via co-evaporation technique to provide concentrations of 5, 10 and 15 at. % Cu. The films were 250-300 nm thick, capped with a thin layer of Pd, i.e. 5-25 nm. The deposition was yielded nanocrystalline or amorphous Mg-Cu thin films depending on the substrate temperature. At 298 K, the films were crystalline, the structure being refined with the increase in Cu content. At 223 K, the films were amorphous, except for Mg:Cu=95:5. The hydrogen sorption of the films was followed by resistance measurements, with the samples heated isochronally, initially under hydrogen and then under vacuum. The resistance data have shown that hydrogen sorption behaviour of thin films was improved by size refinement, and further by amorphization. Among the films deposited, amorphous Mg:Cu=85:15 alloy could absorb hydrogen at room temperature and could desorb it at 223 K (50 &ordm / C), with fast kinetics.

A molecular-level understanding of a heterogeneous catalytic reaction is the key goal of heterogeneous catalysis. A surface science approach enables the realization of this goal. However, the working conditions (ultrahigh vacuum (UHV) conditions) of traditional surface science techniques restrict the investigations of heterogeneous catalysis system under industrial working conditions (atmospheric pressures). Polarization Modulation Infrared Reflection-Absorption Spectroscopy (PM-IRAS) can be operated in both UHV and atmospheric pressure conditions with a wide temperature span while providing high resolution (4 cm-1 is used in this dissertation) spectra. In this dissertation, PM-IRAS has been employed as a major technique to: 1) obtain both electronic and chemical information of catalysts from UHV to elevated pressure conditions; 2) explore reaction mechanisms by in situ monitoring surface species with concurrent kinetic measurements. In this dissertation, NO adsorption and dissociation on Rh(111) have been studied. Our PM-IRAS spectra show a transition of NO adsorption on three-fold hollow sites to atop sites occurs at low temperatures (<275 K). NO dissociation is found to account for this transition. The results indicated the dissociation of NO occurs well below the temperature previously reported. Characterizations of highly catalytically active Au films have also been carried out. Electronic and chemical properties of (1 x 1)- and (1 x 3)-Au/TiOx/Mo(112) films are investigated by PM-IRAS using CO as a probe molecule. The Au overlayers are found to be electron-rich and to have significantly different electronic properties compared with bulk Au. The exceptionally high catalytic activity of the Au bilayer structure is related to its unique electronic properties. CO oxidation reactions on Rh, Pd, and Pt single crystals are explored from low CO pressures under steady-state conditions (less than 1 x 10-4 Torr) to high pressures (0.01-10 Torr) at various gaseous reactant compositions. Surface CO species are probed with in situ PM-IRAS to elucidate the surface phases under reaction conditions. These experimental results are used to correlate reaction kinetics and surface reactant species. It is evident that there is a continuum over the pressure range studied with respect to the reaction mechanism. The most active phase has been shown to be an oxygen-dominant surface. The formation of a subsurface oxygen layer is found to deactivate the reaction.

Im Rahmen der Dissertation wurden Komplexe Intermetallische Phasen (KIP) in den Systemen Ag-Mg und Ag-Ga-Mg dargestellt und charakterisiert. KIP sind Verbindungen, die sich grundlegend von einfachen Metallen unterscheiden. Große Elementarzellen, ein hierarchisch strukturierter Aufbau und inhärente Fehlordnung sind wesentliche Charakteristika. Empirisch wird zudem eine Häufung von strukturchemisch verwandten KIP (Ähnlichkeitsregel) in der Nähe von definierten Zusammensetzungen beobachtet (Häufungsregel). Obwohl nur wenig über die physikalischen Eigenschaften dieser Verbindungsklasse bekannt ist, zeigen neueste Untersuchungen, dass sie interessante Eigenschaften wie ungewöhnliches plastisches Verhalten und Pseudo-Bandlücken in der elektronischen Zustandsdichte in Höhe der Fermi-Energie aufweisen können. Diese Arbeit zeigt exemplarisch, dass in der Chemie der KIP durchaus einfache Regeln (Häufungs-, Ähnlichkeits-, Valenzelektronenkonzentrationsregel) genutzt werden können, um neue Verbindungen mit vorgegebenen geometrischen Baueinheiten aufzufinden. Vereinfachende Annahmen, wie die Aussage, dass zweikomponentige Mackay-Cluster keine Fehlordnung aufweisen oder dass ein Mackay-Cluster maximal 92 Valenzelektronen enthält, erwiesen sich hingegen als falsch. Die Untersuchungen haben gezeigt, dass eine Kombination verschiedener Synthesemethoden notwendig ist. Insbesondere hat sich das Schmelzspinnverfahren, das zur Darstellung kristalliner magnesiumreicher Legierungen angewandt und modifiziert wurde, bei der phasenreinen Synthese der Verbindungen bewährt. Die Entwicklung von Spritzdüsen aus Tantal ermöglichte die kontaminationsfreie Verarbeitung der Mg-haltigen Legierungen. Die Bestimmung der Kristallstrukturen inklusive der Fehlordnungsphänomene war für das Verständnis der Stabilität der KIP entscheidend. Da häufig zwischen verschiedenen Modellen zur Beschreibung der Fehlordnung entschieden werden musste, waren neben präzisen Beugungsdaten genaue Untersuchungen der Präparate mittels chemischer Analytik, Metallographie und WDX hinsichtlich der Zusammensetzung aller Phasen erforderlich. Der magnesiumreiche Teil des binären Phasendiagramms Ag-Mg wurde neu bestimmt. Dabei wurden zwei bislang unbekannte Phasen dargestellt. Die fünf magnesiumreichen Phasen kristallisieren innerhalb eines schmalen Bereichs von nur 9 At.-% Mg. Die Kristallstrukturen dieser Phasen wurden unter besonderer Berücksichtigung der Fehlordnungsphänomene untersucht. Die Verbindungen sind strukturchemisch verwandt und lassen sich den I3-Cluster-Phasen zuordnen. Ag2Mg5 kristallisiert ohne Fehlordnung im Al5Co2-Typ. Die Kristallstrukturen von Ag7Mg26 und Ag17Mg54 lassen sich als fcc bzw. bcc Anordnungen von Mackay-Clustern beschreiben. Es handelt sich um die ersten bekannten binären Phasen, in denen innerhalb von isolierten Mackay-Clustern Substitutionsfehlordnung auftritt. AgMg4 kristallisiert hexagonal in einem eigenen Strukturtyp. Das I3-Cluster-Netzwerk füllt den gesamten Raum bis auf einen annähernd zylindrischen Bereich um 0, 0, z, in dem eine Atom-Split-Position aus drei Lagen vorliegt. Lokal liegen drei unterschiedliche Koordinationspolyeder vor, deren Stapelabfolge in der Kristallstruktur von AgMg4 zufällig ist, jedoch mit kurzreichweitiger Korrelation. Es konnte gezeigt werden, dass sich AgMg4 in eine Tieftemperaturphase umwandelt, in der die Polyeder vermutlich langreichweitig unter Bildung einer Überstruktur ordnen. Der Phasenbestand des ternären Systems Ag-Ga-Mg wurde untersucht und die Kristallstrukturen von sechs neuen Phasen bestimmt. Des weitern wurde eine Verbindung im System Ga-Mg-Pd charakterisiert. Anhand der Strukturtypen Al3Ir und Cu3P sowie den Verbindungen Ag0,55Ga0,45Mg3, Ga4,62Mg13,38Pd7 und Ag1,31Ga1,89Mg7,80 wurde gezeigt, wie die Variation von Strukturmotiven durch geringe Abweichungen von idealer Symmetrie zu zunehmend komplexeren Kristallstrukturen führt, die sich stets von Packungen des Edshammarpolyeders ableiten lassen. Drei ternäre Phasen vom I3-Cluster-Typ konnten identifiziert werden: Neben ternären Varianten der Phasen Ag7Mg26 und Ag17Mg54 kristallisiert Ag0,59Ga0,41Mg2 metastabil im NiTi2-Typ. In den strukturchemisch verwandten Phasen Ag6Ga12Mg11 und Ag21Ga74Mg44 bilden die Mg Atome Netzwerke mit Clatrath-II- bzw. Clatrath-IV-Topologie, die mit Ikosaedern und Frank-Kasper-Polyedern aus Ag und Ga gefüllt sind. Diese Phasen werden wahrscheinlich durch das e/a-Verhältnis der gesamten Struktur im Sinne einer Hume-Rothery-Regel stabilisiert.

Les travaux de recherche présentés ici avaient pour objectif principal la synthèse de copolymères statistiques à base d’éthylène et d’acide acrylique (AA). Pour cela, la déprotection des groupements esters d’un copolymère statistique précurseur, le poly(éthylène-co-(tert-butyl)acrylate), a été effectuée par hydrolyse à l’aide d’iodure de triméthylsilyle. La synthèse de ce précurseur est réalisée par polymérisation catalytique en présence d’un système à base de Palladium (Pd). Le deuxième objectif a été d’étudier et de caractériser des polymères synthétisés à l’état solide et en suspension colloïdale. Plusieurs copolymères précurseurs comprenant différents pourcentages molaires en tert-butyl acrylate (4 à 12% molaires) ont été synthétisés avec succès, puis déprotégés par hydrolyse pour obtenir des poly(éthylène-coacide acrylique) (pE-co-AA) avec différentes compositions. Seuls les copolymères comprenant 10% molaire ou plus de AA sont solubles dans le Tétrahydrofurane (THF) et uniquement dans ce solvant. De telles solutions peuvent être dialysées dans l’eau, ce qui conduit à un échange lent entre cette dernière et le THF, et l’autoassemblage du copolymère dans l’eau peut ensuite être étudié. C’est ainsi qu’ont pu être observées des nanoparticules stables dans le temps dont le comportement est sensible au pH et à la température. Les polymères synthétisés ont été caractérisés par Résonance Magnétique Nucléaire (RMN) ainsi que par spectroscopie Infra-Rouge (IR), avant et après déprotection. Les pourcentages molaires d’AA ont été déterminés par combinaison des résultats de RMN et ii de titrages conductimètriques. A l’état solide, les échantillons ont été analysés par Calorimétrie différentielle à balayage (DSC) et par Diffraction des rayons X. Les solutions colloïdales des polymères pE-co-AA ont été caractérisées par Diffusion dynamique de la lumière et par la DSC-haute sensibilité. De la microscopie électronique à transmission (TEM) a permis de visualiser la forme et la taille des nanoparticules. / The first objective of this research is to synthesize random linear copolymers of ethylene and acrylic acid (AA). The synthesis relies on the deprotection of the functional groups in the copolymer’s precursor, which is represented by poly(ethylene-co-tertbutyl acrylate). The synthesis of the precursor was realized by the catalytic approach, where Pd-based catalytic systems are frequently utilized nowadays. The deprotection was carried out by hydrolysis of the ester functionality using trimethylsilyl iodide agent. The second objective is to investigate and characterize the synthesized polymers in the bulk and in colloidal solution. A set of different precursor polymers with various degrees of molar incorporation of tertbutyl acrylate (from 4 to 12 mol %) was successfully synthesized and deprotected. The resulting poly(ethylene-co-acrylic acid) copolymers were found to be soluble in tetrahydrofuran THF, when the molar incorporation of AA reaches the value of 12 and more. This aspect gave the possibility to study the self-assembly of this copolymer in aqueous medium by slow THF to water exchange (dialysis). It was found that the copolymers self-assemble into nano-sized structures and these nanoparticles remain stable in colloidal solution for extended periods of time. Moreover, it was shown that the nanoparticles formed by the discussed copolymer possess thermo- and pH-responsive behaviour. The polymers synthesized were characterized by nuclear magnetic resonance (NMR) and infrared spectroscopies (IR) before and after deprotection. The bulk samples were analyzed by conventional differential scanning calorimetry and by X-ray diffraction iv technique. The molar percentages of AA were determined using a combination of NMR and conductimetric titration. Colloidal solutions of pE-co-AA copolymers were analyzed by dynamic light scattering and high-sensitivity differential scanning calorimetry techniques. The nanoparticles formed were visualized and characterized by transmission electron microscopy.

Ce travail de thèse s’est intéressé au dépôt électrochimique de filmsde palladium ultra-minces sur Au(111), à leur caractérisation et àl’insertion d'hydrogène dans ceux-ci. La caractérisation des nanofilmsen milieu sulfurique montre des signatures bien définies, qui évoluentavec l’épaisseur des dépôts. Nous avons pu attribuer à chaque pic uneréaction spécifique, en accord avec les mécanismes de croissancerévélés par les mesures SXRD in situ. La croissance pseudomorphede la 1ère couche se fait avec une première étape d'adsorption, suiviepar un mécanisme de nucléation et croissance. La croissance 3D de latroisième couche démarre avant la fin de la deuxième couchepseudomorphe.L'absorption d'hydrogène dans les nanofilms a été étudiée en milieusulfurique. L’isotherme d’insertion présente un élargissement dudomaine de la solution solide, un plateau avec une pente dans ledomaine bi-phasique et une diminution du taux maximal d'insertion del’hydrogène par rapport au Pd massif. Ce taux diminue avecl’épaisseur mai approche celui de Pd massif au déla delà de 15 MC.Deux éléments ont été considérés pour expliquer le comportement desisothermes: les deux premières couches pseudomorphes sontcontraintes par le support et des « tours » tridimensionnelles relaxéesse forment au delà de la 2ème couche. / This thesis focused on electro-deposition, characterization andhydrogen strorage of ultrathin palladium film over Au(111). Theelectrochemical characterization of the nanofilms in sulphuric mediumshows well-defined features evolving with the deposit thickness. Wecould assign each peak to a specific reaction, in agreement with thegrowth mechanisms revealed by in situ SXRD measurements. Thepseudomorphic growth of the 1st layer firstly undergoes an adsorptionstep, followed by nucleation and growth mechanism, as shown bycurrent transient measurements. 3D growth of the 3rd layer beginsbefore the completion of the second pseudomorphic one.Hydrogen absorption in the nanofilms was studied in sulphuric mediumas well. Isotherms show an enlargement of the solid solution domain, asloppy plateau in the two-phase region, a decrease of maximuminsertion ratio (H/Pd)max compared to bulk Pd. This last valuedecreases with film thickness, approaching bulk Pd beyond about15 ML. Two contributions were considered to explain the isothermbehaviour: the two first Pd layers heavily constraint by the substrateand the 3D “towers like” relaxed structures growing on the secondpseudomorphic Pd layer.

Made available in DSpace on 2016-12-12T17:32:57Z (GMT). No. of bitstreams: 1 RESUMO Samanta Rattis.pdf: 133512 bytes, checksum: 4f32bb1bce627b4748ef2be8e61db742 (MD5) Previous issue date: 2014-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The PROFILE PD scale was developed specifically to evaluate patients with Parkinson&#8223;s disease (PD) within the contexts surrounding the International Classification of Functioning, Disability and Health, being directly applied to physical therapy practice. The aim of this study was to perform the translation and cross-cultural adaptation of PROFILE PD scale to Portuguese-Brazil, and to analyze its reliability, validity and other psychometric properties. Thirty three individuals with PD participated in the study. We assessed the clarity of the Brazilian version of the scale assessed by physiotherapists, presence of floor and ceiling effects, inter-rater and test-retest reliabilities, in addition to discriminant validity, concurrent validity (UPDRS), internal consistency, and minimal detectable change (MDC). The understanding level of physical therapists showed high clarity of the scale. Considering total score, the inter-rater and test-retest reliability showed an intra-class correlation coefficient (ICC) of 0.74 and 0.99 respectively. The analysis of concurrent validity showed the Spearman correlation between PROFILE PD Brazilian version and UPDRS with &#961;=0.87. ANOVA oneway showed that PROFILE PD Brazilian version is able to discriminate the subject with PD in mild and moderate stages, and in mild and severe stages. A high internal consistency was found (&#945;=0.90). MDC was 2.41 points and there were no floor and ceiling effects. So, the Brazillian version of PROFILE PD is a reliable and valid instrument that can be used to quantify impairments in body structure and function and limitations of activity and participation in early and mild-stages of PD and can provide an overall summary of the impact of disease being useful for physiotherapeutic practice. / A escala PROFILE PD foi desenvolvida especificamente para avaliar pacientes com Doença de Parkinson (DP) dentro dos contextos da Classificação Internacional de Funcionalidade (CIF), sendo diretamente aplicada à prática fisioterapêutica. O objetivo do presente estudo foi realizar a tradução e adaptação transcultural da escala PROFILE PD para a Língua Portuguesa-Brasil, e analisar sua confiabilidade, validade e outras propriedades psicométricas. Trinta e três indivíduos com DP participaram do estudo. Foram avaliadas: a clareza da versão brasileira da escala por fisioterapeutas, a presença de efeito piso e teto, as confiabilidades inter-avaliador e teste-reteste, além da validade discriminante, validade concorrente, consistência interna, e a mínima mudança detectável (MDC). O nível de entendimento de profissionais fisioterapeutas demonstrou alta clareza da escala. Considerando o escore total, as confiabilidades inter-avaliador e teste-reteste apresentaram um coeficiente de correlação intra-classe (CCI) igual a 0,74 e 0,99 respectivamente. A análise da validade concorrente demonstrou a correlação de Spearman entre a versão brasileira da PROFILE PD e a UPDRS &#961;=0,87. A ANOVA oneway mostrou que a versão brasileira da PROFILE PD pode discriminar o indivíduo com DP entre os estágios leve e moderado, e leve e grave. Uma alta consistência interna foi encontrada (&#945;=0,90). A MDC foi de 2,41 pontos, e não foi encontrado efeito piso e teto. A versão brasileira da PROFILE PD é um instrumento válido e confiável capaz de quantificar alterações na estrutura e função corporal e limitações de atividade e participação nos estágios leve e moderado da DP, fornecendo um perfil do impacto da doença nestes contextos, sendo diretamente aplicável à prática fisioterapêutica.

Made available in DSpace on 2015-05-14T13:21:08Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2470601 bytes, checksum: bbe63c6c08f3ff229939be1fa3d736d8 (MD5) Previous issue date: 2011-11-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aim of this study is the preparation and characterization of the Pd/C catalyst for the stearic acid decarboxylation in order to obtain paraffinic biodiesel. The precursors used in the coal preparation were the coconut endocarp and the Manila palm sheath. These coals were chemically activated and by microwave hydrothermal treatment with HNO3 solution. Its characterization showed that the microwave activation induced a decrease in catalysts microporous structure. The porous structure of each coal was determined by N2 adsorption at 77 K. The isotherm data were by BET, Langmuir, t-plot and BJH methods. The ZCP values and the ash content were determined. The identification and quantification of chemical groups on the activated coals surface used the Boehm method and infrared spectroscopy, which showed formation of carboxylic groups for all samples. The coals originated from the coconut endocarp (CAE AC and CAE MW), activated by both methods, had higher SMIC than the coals from the palm sheath (CAB and CAB AC MW). The CAB coals are more mesoporous, while the CAE coals have a more relevant microporous structure. The Pd/C catalysts were prepared by dry impregnation and by alcohol reduction. The catalysts characterization was performed using the SEM-FE, H2 chemisorption, N2 adsorption/desorption of at 77 K and FTIR. The metallic phase deposition favored a decrease in total surface area. The catalysts synthesized by dry impregnation showed larger micropore areas. The SEM-FE showed that in the catalysts prepared by alcohol reduction the metal deposition occurred preferentially at the surface, where as it in the catalysts prepared by dry impregnation, probably occurred within the pores. The Pd/C catalysts used in the catalytic decarboxylation reaction of stearic acid, at 350°C in H2 atmosphere showed conversions and high selectivity for heptadecane. The catalysts derived from coal CAE showed higher selectivity in relation to the formation of the desired product, the heptadecane. We observed a trend of higher conversions for the catalysts synthesized by dry impregnation. Some catalysts showed deactivation after three hours of reaction. / A proposta deste trabalho é estudar a preparação e caracterização do catalisador Pd/C para a descarboxilação do ácido esteárico, a fim de obter biodiesel parafínico. Os precursores utilizados na preparação dos carvões foram o endocarpo do coco da baía e a bainha da palmeira de manila. Estes carvões foram ativados quimicamente e por microondas com solução de HNO3. A estrutura porosa de cada carvão foi determinada por adsorção de N2 a 77 K. Os dados das isotermas foram tratados pelas metodologias de BET, Langmuir, t-plot e BJH. Sua caracterização permitiu concluir que a ativação por microondas induziu uma diminuição da estrutura microporosa dos catalisadores. Foram determinados os valores de PCZ e teor de cinzas. Na identificação e quantificação dos grupos químicos da superfície dos carvões utilizou-se o método de Boehm e espectroscopia de infravermelho, que evidenciaram a formação de grupos carboxílicos para todas as amostras ativadas. Os carvões originados do endocarpo do coco ativados quimicamente e por microondas (CAE AC e CAE MW) apresentaram SMIC mais elevadas do que os carvões provenientes da bainha da palmeira (CAB AC e CAB MW). Os carvões CAB são mais mesoporosos, enquanto os CAE possuem estrutura microporosa mais relevante. Todos os carvões ativados apresentaram PCZ ácido. A ativação do CAE por microondas favoreceu o aumento da estrutura mesoporosa, com significativa diminuição da microporosa. Os catalisadores Pd/C foram preparados por impregnação seca e por redução por álcool. A caracterização destes catalisadores foi feita através do FE-SEM, quimissorção de H2, adsorção/dessorção de N2 a 77 K e FTIR. A deposição da fase metálica favoreceu uma diminuição da área superficial total. Os catalisadores sintetizados por impregnação seca apresentaram maiores áreas de microporos. O FE-SEM mostrou que nos catalisadores preparados por redução por álcool a deposição do metal ocorreu preferencialmente na superfície, enquanto nos preparados por impregnação seca, possivelmente ocorreu dentro dos poros. Os catalisadores Pd/C utilizados na reação de descarboxilação catalítica do ácido esteárico a 350 ºC, em atmosfera de H2 apresentaram elevada atividade catalítica e seletividade para o heptadecano. Os catalisadores derivados do carvão CAE mostraram seletividade superior em relação à formação do produto desejado, o heptadecano. Foi observada uma tendência de conversões maiores para os catalisadores sintetizados por impregnação seca. Alguns catalisadores apresentaram desativação após três horas de reação.