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Desenvolvimento de um método para quantificação simultânea de sulfametoxazol e trimetoprima em ovos de galinha utilizando a cromatografia liquida de alta eficiência bidimensional
(Universidade Federal de São Carlos, 2007-04-13) Paula, Fernando Campos Costa Rodrigues de; Cass, Quezia Bezerra; https://lattes.cnpq.br/9197210255594409; https://lattes.cnpq.br/0385617953338357
This work reports the investigation of a series of bovine serum albumin (BSA) restricted access media columns (RAM) for on-line egg samples deproteinization. High exclusion percentage of egg s proteins were obtained with the three RAM BSA columns prepared (C8, C18 and phenyl) using only water as eluent. However, an increase of pressure of the chromatographic system was observed at each injection, which made unfeasible the use of these columns for direct injection of the egg samples. To prolong the life-time of the RAM-BSA columns, acetonitrile was used as a protein precipitate agent. This clean-up procedure allowed the repetitive injection of 300 µL of whole egg samples. For the simultaneous quantification of sulfamethoxazole (SMX) and trimethoprim (TMP) in eggs samples, RAM-BSA columns, in different lengths (10 and 5 cm) sizes and different chromatographic conditions were thoroughly evaluated. A bidimensional higher performance liquid chromatography configuration having a RAM C18 BSA column in the first dimension, and a C18 analytical column in the second dimension were used for simultaneous quantification of these antibiotics. The developed method showed good selectivity, accuracy and precision with limits of quantification 80 ng/mL for both compounds. Thus, the validated method is reliable and sensitive for monitoring residues in whole eggs samples.
A construção da subjetividade nacional no movimento "o melhor do Brasil é o brasileiro"
(Universidade Federal de São Carlos, 2007-04-13) Polonio, Maristela; Sargentini, Vanice Maria Oliveira; https://lattes.cnpq.br/1406919572611392; https://lattes.cnpq.br/5747038186720459
What does it means to claim to be brazilian? How nationalist campaigns promoted by the State may affect the subject? To answer these questions and to take off from the evidence principles as of the nation and to problematize the construction of the subject of the nationality, we developed the present work. Based on the discoursive theory derived from Michel Pêcheux and Michel Foucault, this research intends to understand how is materialized the control of the national subjectivity, observing the discoursive event where is constructed the publicity movement called: The best of the Brazil is the brazilian , produced in 2004, under the current president administration. Concepts formulated in the scope of the french Discourse Analysis, as discoursive event and memory guide the analysis about the verbal materiality of the texts that integrate the referred movement, and the results reveal the existence and the functioning of one kind of power the governability , described by Foucault (2004) that happens to the subjects, standardizing a certain way of being, identified to the brazilian nation. We noticed that there is in the official publicity pro- brazilian auto esteem the construction of one national subject produced in the patterns of the democratic nation profile, that the globalized capitalism proposes. This deals with the production of a brazilian subject identified to one nation, which singularity resides in the congregation of globalized traces.
Catalisadores à base de Mo, NiMo e CoMo suportados sobre y-Alumina ou Al-MCM-41 - Avaliação na hidrodessulfurização do dibenzotiofeno
(Universidade Federal de São Carlos, 2007-04-13) Baston, Eduardo Prado; Urquieta-González, Ernesto Antonio; https://lattes.cnpq.br/1277176561519941; http://lattes.cnpq.br/2389975677904655
The effect of the γ Al2O3 synthesized by Sol-Gel method and Al-MCM-41 mesoporous molecular sieves used as supports in the preparation of Mo, NiMo and CoMo catalysts was studied. The activity and selectivity of the catalysts were evaluated through the HDS of DBT using a batch reactor operated at 300 ºC under 6,9 MPa of H2. TG/DTG, chemical analysis, XRD, N2 adsorption/desorption, DRS-UVVIS and H2-TPR were used to sample characterization. XRD and N2 adsorption/desorption data showed that the method used to synthesize Al-MCM-41 allowed the preparation of solids with well ordered mesoporous array, high specific surface area and mean pore diameter of 2,87 nm. Otherwise, the γ Al2O3 prepared via Sol-Gel procedure presented a higher specific surface area than a commercial γ Al2O3. After the Mo, Ni or Co impregnation, the supports preserved their structural properties, however a diminution in their specific surface are was observed. The effect of the metal impregnation was more pronounced in the catalysts supported on γ Al2O3, leading to a more diminution of the area and in the mean pore diameter. XRD, H2-TPR and DRS-UVVIS data evidenced the presence of MoO3, NiMoO4 or CoMoO4 species in prepared catalysts, which are the precursors in the obtention of the active phase after sulfidation. The catalysts were highly actives in the HDS of DBT, with the bimetallic ones (Mo and Ni (or Co)) presenting high conversion values (higher than 70 %) after 8 hours on stream. That behavior confirmed the important role of Ni and Co as promoter in the HDS of DBT. The occurrence of the cracking reaction was influenced by the specific surface area of the support and the nature, strength and distribution of the acid sites, with Al-MCM-41 being more active. Cyclohexylbenzene (CHB) produced by DBT hydrogenation/desulfurization (HYD) or Biphenyl produced by direct desulfurization (DDS) were the main reaction products. Nevertheless, the Mo and NiMo catalysts favored the HYD route, due to the more hydrogenation capability of the Ni. On the other hand, the CoMo catalysts were more effective in the DDS route.