Orientador: Claudio Airoldi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-23T02:01:02Z (GMT). No. of bitstreams: 1 MeloJunior_MauricioAlvesde_D.pdf: 8850225 bytes, checksum: 8531789c5f9acab757429aa59582c7d6 (MD5) Previous issue date: 2013 / Resumo: Foram sintetizadas sílicas mesoporosas híbridas a partir da funcionalização da SBA-15 e filossilicatos de cobalto e níquel com macrociclos orgânicos contendo sítios básicos para a sorção dos íons metálicos tóxicos Pb, Cd e Cu. A SBA-15 e o filossilicatos de magnésio também foram modificados com cadeias orgânicas contendo diferentes quantidades de átomos de enxofre para serem aplicados na sorção de íons complexos de ouro e de metais do grupo da platina com o intuito de otimizar as condições adotadas para a extração destes metais preciosos de seus minérios. Os materiais contendo macrociclos orgânicos foram formados a partir de sucessivas reações nas superfícies com diferentes moléculas orgânicas para conter os centros básicos nitrogênio, oxigênio e enxofre. As técnicas de caracterização confirmaram as formações das estruturas mesoporosas e lamelares, mostrando a presença de cadeias orgânicas pendentes contendo os grupos funcionais de interesse. Os híbridos funcionalizados com macrociclos apresentaram-se efetivos nas sorções dos metais tóxicos, com alta capacidade para o íon Pb quando estão funcionalizados com macrociclos contendo enxofre. Enquanto que, no geral, as capacidades de sorção de todos os materiais tornaram-se maiores com o aumento das quantidades de centros básicos. Estas capacidades de sorção ainda sofrem um aumento após a formação dos macrociclos. As sorções dos complexos de metais preciosos foram efetivas em todos os casos, com destaque para tetracloroaurato e tetracloropaladato, que apresentaram altos valores de sorção. Ótimos valores também foram obtidos na sorção do complexo aurotiossulfato com o filossilicato de magnésio funcionalizado com grupos tiol. As titulações calorimétricas dos metais tóxicos com as matrizes contendo macrociclos orgânicos indicaram processos favoráveis de interação dos sítios básicos com os cátions em solução aquosa, devido a valores negativos de energia de Gibbs, em um processo espontâneo, e valores positivos de entropia. Os valores de entalpia mostram que todas as interações metais/centros básicos na interface sólido/líquido são exotérmicas / Abstract: This thesis reports the syntheses of hybrid mesoporous sílicas, through the functionalization of SBA-15, and cobalt and nickel phyllosilicates functionalized with organic macrocycles containing basic sites for the sorption of the toxic metallic ions Pb, Cd and Cu. SBA-15 and magnesium phyllosilicates were also modified with organic chains containing different amounts of sulfur atoms to be applied to the sorption of complex ions of gold and platinum group metals. This is done in the aim of optimizing the conditions adopted in the extraction of these precious metals from their ores. The materials with pendant organic macrocycles were formed through successive reactions on the surfaces with different organic molecules possessing nitrogen, oxygen and sulfur basic centers. The characterization techniques confirmed the formation of mesoporous and layered structures, showing the presence of pendant organic chains with the desired functional groups. The hybrids functionalized with macrocycles were effective in the sorption of toxic metals, with high sorption capacities for Pb when the solids are functionalized with macrocycles containing sulfur atoms. Whereas the sorption capacities of all materials were improved with the increase of basic centers amounts. These sorption capacities were even improved after the macrocycles formation. The sorption of precious metals complexes were effective in all cases, especially for tetrachloroaurate and tetrachloropalladate, which presented high sorption values. Exceptional values were also acquired in the sorption of aurothiosulfate complex by the magnesium phyllosilicate functionalized with thiol groups. The calorimetric titrations of toxic metals with the matrices containing organic macrocycles indicated favorable processes for the interaction between the basic centers and the cations in aqueous solution, due to negative values of Gibbs energy, in a spontaneous process. The results also indicated positive values of entropy. The values of enthalpy showed that all the metal/basic centers interactions at the solid/liquid interface are exothermic / Doutorado / Quimica Inorganica / Doutor em Ciências

Malgré ses avantages économiques et environnementaux, le procédé de reformage à sec du méthane sur des catalyseurs au nickel supporté se heurte encore à des problèmes de frittage de la phase active (un métal de transition) et de dépôt de carbone, ce qui entraîne une diminution de l'activité catalytique. Cette thèse porte sur l'étude de l'effet de confinement du nickel dans des catalyseurs à base de silice mésoporeuse pour la production de gaz de synthèse par reformage du méthane par le CO2. Dans cette étude, les échantillons ont été caractérisés par physisorption de N2, DRX, MET/MEB, RTP, et, en plus, par Raman, SPX, HTP/SM, ATG/SM pour les catalyseurs après test catalytique. Les résultats montrent qu'un support mésoporeux bien structuré ayant une grande surface spécifique et un grand volume poreux est important pour une meilleure dispersion et stabilisation de la phase active à l'intérieur de la porosité. La silice mésoporeuse de SBA-15 (préparée en grande quantité), composée de grains allongés, semble être appropriée pour atteindre cet objectif. Il est de plus démontré que la formation de petites particules bien confinées à l'intérieur des pores favorise la résistance au dépôt de carbone. Ceci peut être obtenu en imposant un traitement hydrothermal au support, en utilisant la méthode deux solvants pour le dépôt de Ni, en passant à une réduction directe des échantillons non calcinés, en ajoutant du Rh en faibles quantités ou en utilisant du Ce comme promoteur, à condition que le Ni et Ce soient en interaction. / Although economically and environmentally advantageous, the methane dry reforming process using supported nickel based catalysts still faces problems of active phase (a transition metal) sintering and of carbon deposition, which result in catalytic activity loss. This thesis is focused on the study of the confinement effect of nickel in mesoporous silica-based catalysts for syngas production by reforming of methane with CO2. In this study, the samples were characterized by N2 sorption, XRD, TEM/SEM, TPR, in addition to Raman, XPS, TPH/MS, TGA/MS for the spent catalysts. The results indicate that a well-structured mesoporous support with high surface area and large pore volume is important for better dispersion and stabilization of the active phase inside the porosity. The mesoporous SBA-15 silica support (prepared in large quantity), composed of elongated grains, appear to be suitable for the purpose. Moreover, it is demonstrated that the formation of small nickel particles well-confined inside the pores favors carbon resistance. This can be achieved by applying hydrothermal treatment to the support, using two solvents method for Ni deposition, using direct reduction of uncalcined samples, adding Rh in small quantities or promoting with Ce, provided that Ni and Ce are in interaction.

The thesis is focused on the production of a seamless ring manufactured from low-alloyed steel 15 142, which fills the function as a large-dimensional bearing. On the basis of suitable production technologies analysis, the radial axial rolling method was chosen and a specific manufacturing process was proposed. During the manufacturing time, the creation of the forging defects in the transfers forms were occurred, which was totally undesirable. By changing the parameters of the machine, in particular the rolling curve and the temperature, the process was optimized and the production performed completely without defects.

In the Visual - Weld and Sysweld programs, a simplified simulation of the welding process of the turbine rotor made of 27NiCrMoV 15-6 substance was performed. The numerical analysis took place at the equal temperature of preheating and it covered both minimal and maximal percent chemical composition. The simulation proved that the percent deviations of elements in the substance change the speed necessary for reaching of the bainitic structure. Simulation results were verified by a practical experiment. Two weld beads were welded to a base substance by MIG method: one bead at the temperature of 200°C, the other one at the temperature of 300°C, both with the same specific input caloric QS. Both micro and macrostructure of the base substance and TOO was evaluated, and the progression of the hardness was measured as well. The deviations fell within the acceptable 15% range.

In Ergänzung einer von Curt Weikinn (1888–1966) zusammengestellten und vor 50 Jahren in den Acta Hydrophysica erschienenen Auflistung sehr starker bzw. verbreiteter Hagelfälle in den Jahren 1100–1400 wird nachfolgend die als Fortsetzung gedachte, jedoch bis jetzt unveröffentlichte Zusammenstellung gleichartiger Ereignisse aus dem 15. Jahrhundert wiedergegeben. / In addition one of Curt Weikinn (1888–1966) developed and shortly after his death in the Acta Hydrophysica published list of very strong or widespread hailstorms in the years 1100–1400 is below the imaginary as a continuation, but as yet unpublished compilation of similar events from 15th century reproduced.

Med denna studie har vi som avsikt att skapa en förståelse om hur villkoren ser ut för 15-timmarsbarnen i Ängelholm. Vårt tillvägagångssätt handlar om att använda enkäter och intervjuer för att besvara våra frågeställningar. Våra huvudsakliga frågeställningar handlar om hur pedagoger ser på sitt pedagogiska uppdrag gällande 15-timmarbarnen, hur föräldrar till dessa barn ser på sitt barns förskolgång och hur politikerna ser på bestämmelser kring 15-timmarsregeln. / In the Education Act (of Sweden) its described that children to parental leave or children to unemployed have the right to attend at least tree hours a day or 15 hours a week, at preschool. We’ve studied various aspects of the terms of 15 hour children in Ängelholm. We have chosen to approach our issue by using interviews and questionnaires with parents, preschool-teachers and a politician. Our main questions is about how parents look at their children’s stay in preschool, how preschool- teachers look at their pedagogical assignment and how the politician approaches the regulation around the terms of the15-hour rule. After recalling some aspects of Uri Bronfenbrenners theory, we present an approach to his model and use the different kind of levels to make our research findings legible. Further on we are using prior research as Qvortrup and Halldén. Their research concerns preschool as an institution. To sum up we have come to the conclusion of that there is a big lack of communication between the different information groups. The municipality has to take a decision, according to these children, based on the financial situation; the preschool teachers have no power to influence the decision of the municipality and don’t have as much time for the parents as they wished. The parents are concerned that there children don’t have the time they need in preschool and that there children are going to miss out on activities that the other children at preschool gets.

No description available.

Crystal structures of anhydrous pinacol, the hexagonal pinacol, pinacol monohydrate, and pinacol hexahydrate were studied. In all the structures crystal packing is unusual and complicated. The origin of the complexity may be the difficulty in filling space densely and while also satisfying the H-bonding requirements when the molecule has few internal degrees of freedom. Five 15-crown-5 complexes of M(NO3)2 (M = Cu, Zn, Mg, Co, Mn) were synthesized and characterized using X-ray diffraction and differential scanning calorimetry. The system is rich in polymorphs. Nine definite solid-state phases were identified. More phases probably exist in the solid state at temperatures slightly above the room temperature. Most phase transformations in this system take place in single crystals without the loss of crystallinity. The nine phases crystallize in five crystal structures. The crown ether ligands have very similar conformation in all the structures. The asymmetric units in all the structures are complicated and pseudosymmetric, which is the consequence of the presence of the packing problem. The origin of the packing problem that leads to the complicated phase behavior is the odd number of -CH2-O-CH2- units in the crown ether ligand.

Klebsiella spp. are opportunistic pathogens that cause hospital and community acquired infections such as pneumonia, urinary tract infection, septicaemia, soft tissue infections, liver abscess, and meningitis. Multidrug-resistant strains possessing extended-spectrum β-lactamases (ESBLs) has become an increasing problem worldwide. The over use and, in some cases, misuse of antibiotics in humans and in animal husbandry has been cited as a responsible factor in the development of drug resistance in all bacterial species. The advancing age; female gender, hospital crossinfection, the food chain trade and human migrations have contributed to increase the risk for community-acquired ESBL. A total of 223 isolates collected in 2006 and 2007 at Royal Infirmary of Edinburgh, Scotland, 219 K. pneumoniae, 2 K. oxytoca, 1 Enterobacter cloacae, and one isolate Salmonella enterica were identified by API 20E and confirmed genotypically with gyrA PCR-RFLP method. The antimicrobial susceptibility results showed that 34 (15.2%), 36 (16.1%), 35 (15.7%), 45 (20.2%), 30 (13.5%) and 55 (24.7%) of these strains were found to be resistant to cefotaxime, ceftazidime, ceftriaxone, naladixic acid, ciprofloxacin and cefoxitin. None of the isolates were found resistant to meropenem keeping carbapenems the drug of choice for the treatment of multiresistant isolates. The overall frequency of ESBL producers observed in this study was 35 (15.7%) most of them 32/35 (91.4%) were from K. pneumoniae. The genetic analysis showed that SHV β-lactamases were detected in 32, whereas TEM and CTX-M were detected in 24 and 16 respectively. From the ESBL-producing isolates, molecular methods identified nine strains possessing ESBL-SHV genes (1 strain blaSHV-5, 1 strain blaSHV-80 and 8 strains blaSHV-12), whereas the remaining were from the “non-ESBL” producing strains. Conjugation methods demonstrated that 29/32 isolates harboured transferable blaSHV genes. The large SHV transposon-borne promoters were amplified from only one non-transferable blaSHV-11, 15 isolates produced the small SHV transposon-borne promoters. Furthermore, the IS26 was found 73bp upstream of the blaSHV gene in all small SHV transposon-borne promoters. A new blaLEN gene was identified from K. pneumoniae (KpII) phylogenetic group but remained susceptible to all cephalosporins. Sixteen (7.3%) of K. pneumoniae isolates were found to be producers of the CTX-M- 15 ESBL, of which two isolates (12.5%) were reported to be from communityacquired infections. The insertion sequence ISEcp1 was detected by sequencing 48 nucleotides upstream of blaCTX-M-15 in all isolates but one. Five different clones of CTX-M-15-producing isolates were identified by PFGE. The findings indicated a higher prevalence of qnr genes than in previous studies but still low in general. By PCR, 18 (8%) (11 qnrB1, 2 qnrB6 and 5 qnrA1) genes were identified from K. pneumoniae isolates. Also, the findings indicated the frequent coexpression of fluoroquinolones and ESBLs resistance in the same isolate. Two K. oxytoca strains were isolated from urine and blood specimens of hospitalized patients. Both strains were positive for the blaOXY-2 gene. One strain showed resistance to pencillins, monbactams, cephalosporins including cefotaxime and ceftazidime but was not inhibited by clavulanic acid. It differed by an amino acid substitution Ala237→Thr, which enhances the binding of cefotaxime. S1-nuclease plasmid profiles were obtained for some isolates. A total of one to two plasmids, ranging in size from approximately 40 to 210 kb, were observed per strain. The plasmids from 24 ESBL K. pneumoniae strains were assigned to be IncN or IncFII replicons. Analysis of phylogenetic groups showed that the majority of K. pneumoniae isolates were belonged to KpI-type. Both K. oxytoca strains were assigned to be KoII phylogenetic group based on rpoB and gyrA sequencing. Integrons are capable of capturing and mobilizing genes called gene cassettes which play an important role in the dissemination of antimicrobial resistance through horizontal transmission. In fact, the present study indicated a high frequency of occurrence of class 1 integrons among ESBL-positive K pneumoniae. Three isolates positive for class 1 integrons were found positive for class 2 integrons as well. Class 1 integrons including dfr, aadA and ereA2 gene cassettes have been identified by sequencing, which confer resistance to trimethoprim, streptomycin/spectinomycin and erythromycin respectively. In conclusion, the results from this thesis report the emergence of hospital and community-acquired highly resistant CTX-15 β-lactamase in the Edinburgh, Scotland. The prevalence of ESBL-producing isolates in Scotland is still much lower than in many other European countries. The dissemination of SHV- and TEM- β- lactamase types in this study is more predominate than CTX-M-15.

Memoria para optar al Título Profesional de Médico Veterinario / El ciclo estral de la hembra canina presenta algunas características únicas al ser comparadas con otras especies de mamíferos domésticos. Sin embargo, poco se conoce de las características del desarrollo folicular en relación a otras especies. El Factor de Crecimiento Diferencial 9 (GDF-9) y la Proteína Morfogenética Ósea 15 (BMP-15), son miembros de la superfamilia de Factores de Crecimiento Transformantes Beta (TGF-β), y han demostrado un rol fundamental en el desarrollo folicular en muchas especies. El objetivo de este estudio fue analizar la presencia de ambas proteínas en células foliculares proveniente de folículos antrales del ovario canino mediante citometría de flujo. Se obtuvieron células de la granulosa y del cúmulo a través de aspiración y raspado de folículos antrales de distintos niveles de desarrollo y en distintas etapas del ciclo estral. Las células se fijaron e incubaron con anticuerpo anti GDF-9 humano y anti BMP-15 de ratón (1:100) y anticuerpos secundarios conjugados con FITC y PerCP (1:500), respectivamente. Al análisis por citometría se hizo un Gate discriminatorio por tamaño y complejidad en el Dot plot inicial y adicionalmente se discriminó con marcadores de CD45 para leucocitos y yoduro de propidio (IP) para eritrocitos y debris en los histogramas correspondientes. Los resultados se analizaron con ANOVA y regresión lineal. La expresión de GDF-9 disminuyó (P<0.05) a medida que avanzó el desarrollo folicular en Anestro y Proestro/Estro, pero aumentó (P<0.05) en Diestro. BMP-15 aumentó (P<0.05) su presencia en folículos antrales más desarrollados en la etapa de Anestro, disminuyendo (P<0.05) en Proestro/Estro al alcanzar un mayor nivel de desarrollo. Estas proteínas por tanto, se expresaron en las células foliculares de caninos en distintas etapas del ciclo estral y de manera diferente durante el desarrollo folicular, donde ambas podrían estar relacionadas con las características particulares. / The estrous cycle of the bitch presents unique features when compared to other domestic mammals, however, little is known about the characteristics of the follicular development compared with other species. The Growth Differential Factor 9 (GDF-9) and Bone Morphogenetic Protein 15 (BMP-15) are members of the Transforming Growth Factor (TGF-β) superfamily and have demonstrated an important role during the follicular development of many species. The aim of this study was to analyze the presence of both proteins in the follicular cells from canine ovarian antral follicles by flow cytometry. Granulosa and cumulus cells were obtained by aspiration and scraping of antral follicles from different sizes and stages of the estrous cycle. Cells were fixed and incubated with first antibodies against human GDF-9 and mouse BMP-15 (1:100) and second antibodies conjugated with FITC and PerCP (1:500), respectively. A size and complexity discriminatory gate was used for the cytometryc analysis in the initial dot plot and, additionally, a CD45 marker for leukocyte and Iodum Propide for erythrocyte and debris discrimination in the corresponding histograms. The results were analyzed with ANOVA and lineal regression. GDF-9 expression decreased (P<0,05) during follicular development in Anestrous and Proestrous/Estrous, but increased during Diestrous (P<0,05). BMP-15 expression increased (P<0,05) during follicular development in Anestrous, but decreased in roestrous/Estrous (P<0,05) compared to small and medium sizes. Therefore, these proteins are expressed in canine antral follicle cells during different stages of the estrous cycle and at different levels of develop of the antral follicle, where both may be related to the special features of the bitch. / Financiamiento: Proyecto Fondecyt No. 1140658