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O papel dos sistemas agroflorestais na recuperação da qualidade do solo no assentamento Sepé Tiarajú, SP, na percepção dos agricultores
(Universidade Federal de São Carlos, 2012-05-25) Junqueira, Alexandre da Costa; Schlindwein, Marcelo Nivert; https://lattes.cnpq.br/9690898537150950; https://lattes.cnpq.br/1646358534097663
Agroforestry systems have been an alternative of agricultural production that combine food production with the recovery and conservation of the natural resources in the settlement Sepé-Tiarajú; first SDP (Sustainable Development Project) settlement in the State of São Paulo and located in the sugarcane region of Ribeirão Preto (SP). This study evaluates the effects of agroforestry systems on soil quality; using 10 qualitative indicators of soil quality; comparing the moment when there were no SAFs with the present moment. For this; semistructured interviews were made and the reports of 10 farmers were analysed qualitatively. The results obtained showed that the SAFs contributed to reduce soil compaction; erosion control; increase of humidity retention; soil darkening; increased occurrence of indicator plants of good quality soil; improvement in growth; development; appearance and production of crops; increased occurrence of worms; insects and other organisms in soil and reduction of pest and diseases attacks.
Cromatografia quiral em escala preparativa: estudo de casos e aplicação
(Universidade Federal de São Carlos, 2012-05-25) Lourenço, Tiago de Campos; Cass, Quezia Bezerra; https://lattes.cnpq.br/9197210255594409; https://lattes.cnpq.br/7899438213629513
Different types of preparative chromatography techniques were applied to the enantiomeric purification of a series of chiral drugs. The efficiency of multicolumn chromatography with variable zones (VARICOL®) process and also the application for the resolution of drugs modafinil, atenolol and albendazole sulfoxide were investigated and is fully discussed in this work. The initial conditions for the separations were determined by theoretical simulation, using the software HELP 10.3 by Novasep®. For the modafinil separation, different feed concentrations were evaluated for the same zone distribution and period. The most efficient process provided 96.0% of enantiomeric purities for both enantiomers with a production rate of 2.24 g/dia. The enantiomers of albendazole sulfoxide were separated by the VARICOL® process, and the enantiomeric purities obtained were of 99.5% and 99.0% for rafinate and extract, respectively, with a production rate of, approximately, 2.0 g/dia. For both developed method, the mobile phase used was exclusively methanol, which was recovered around 95 %. Atenolol was efficiently enantiorresolved by CHIRALCEL OD®, however, the enantiomers were not obtained with high purities by the VARICOL® process due to their low solubility in the mobile phase and the high cycle time. This work describes also, for the first time, the absolute configuration of albendazole sulfoxide as (−)-(S) and (+)-(R)- enantiomers.To this end, vibrational circular dichroim and theoretical calculations were applied. The albendazol sulfoxide enantiomers were used for In Vitro tests against Taenia Solium cysts, the macroscopic, the microscopic and the biochemical behavior for the cysts were evaluated; (+)-(R)-albendazole sulfoxide was the enantiomer with the highest anthelmintic effect. Elution chromatography was used for the resolution of 3,4-methylenedioxymethamphetamine (MDMA) and omeprazole. MDMA was separated by the use of recycling in mass overload conditions, enantiomeric purities of 99.0% and 96.0% were obtained for (R)-(-)- and (S)-(+)- MDMA, respectively, with production rate of 40.0 mg/mL. Racemic MDMA and both enantiomers were used to evaluate oxidative stress status parameters. The enantiomers showed distinct effects in the liver redox state with the (R)-(−)- enantiomer being the responsible for the highest oxidative damage. For omeprazole separation, stack injections with mass overload was used, a production rate of 1.10 g/dia and high enantiomeric purities (99.0%) were attained and for this process, furthemore the mobile phase was totally recycled.
Complexos fosfínicos de Ru(II) e Ru(III) com fármacos anti-tuberculose e seus derivados
(Universidade Federal de São Carlos, 2012-05-25) Cunha, Lucas Vinicius Pozzi da; Batista, Alzir Azevedo; https://lattes.cnpq.br/6469642481998660; https://lattes.cnpq.br/3169524306564408
In this work were synthesized ruthenium complexes using pyrazinamide (PZA), a first-line drug in the treatment of tuberculosis, as well as isonicotinamide (ins) and isonicotinic acid (INA), isoniazid derivatives, as ligand. The reason why some drugs are been used as ligand is to enhance their activit or minimize the side effects. These mer-[RuCl3(dppb)(L)] (L = INA, PZA and ins) complexes was characterized by cyclic voltammetry, FTIR, UV-Vis, elemental analysis and conductivity. Electrochemical studies showed the presence of Ru (III) and other species, both binuclear and mononuclear that are generate in solution by a specific potential application, as described in the literature for mer-[RuCl3(dppb)(H2O)]. The assignment of the main absorption bands in FTIR spectra showed the appearance of metal-ligand bonds. The UV-Vis spectra showed three bands related to ligand charge transfer to the metal (LMCT), and the neutrality of these complexes was confirmed by conductivity. The series of complexes [RuCl(ins)(dppb)(N-N)]PF6 was characterized by NMR, cyclic and differential pulse voltammetry, FTIR, UV-Vis, X ray diffraction, elemental analysis and conductivity. The presence of two doublets in the NMR spectra showed that the phosphorus atoms are not equivalent. When the chloride ligand is exchanged by a N-heterocyclic ligand the redox potential was increased if compared with the precursor complex potential, due to the nature of the π-receptor ligand ins. The crystal structures of complexes [RuCl(ins)(dppb)(bipy)]PF6 and [RuCl(ins)(dppb)(phen)]PF6 were determined by X ray and were suggested that the ins ligand is in trans position to the phosphorus atom of dppb. The conductivity indicated the presence of an anion PF6, stabilizing the complexes. Anti-M. tuberculosis and cytotoxicity studies were performed for these complexes [RuCl(ins)(dppb)(N-N)]PF6 and mer-[RuCl3(dppb)(L)] and their respective free ligands.
Textos da Revista Ciência Hoje como recurso didático : análise e possibilidades de uso no ensino médio de química
(Universidade Federal de São Carlos, 2012-05-25) Cantanhede, Severina Coelho da Silva; Queiroz, Salete Linhares; https://lattes.cnpq.br/7925870606416937; https://lattes.cnpq.br/6339973892203174
This research investigated the use of popular science texts (PST) related to chemistry published in magazine Ciência Hoje (sections O Leitor Pergunta and Mundo de Ciência) between 2004 and 2008 and analyzed a teaching strategy based on the use of those texts. The objective of this study is to understand how they can be used in high school chemistry classes and discuss features that can assist teachers in using them as a didactic resource based on the studies of Salém and Kawamura (1999), Ribeiro and Kawamura (2005), Amaral et al. (2006) and Ferreira (2009). A significant number of articles in this area were found in the magazine Ciência Hoje: a total of 133 articles in the period investigated (all sections), from which 32 were found in the section the O Leitor Pergunta and 41 in the section Mundo de Ciência. The articles found in the two sections studied include those that address chemistry-related content, those that deal with transverse themes (especially Health and Environment), and those that deal with frontier themes (physics, cosmology, biochemistry, etc.). Thus, teachers who decide to use PST as a didactic resource in chemistry teaching have a large and varied collection of texts to choose from in this magazine. In order to facilitate the selection of texts, a guide was created for teachers including the contents (chemistry, transverse themes, and frontier themes; general chemistry, physical chemistry, and organic chemical) for each PST analyzed. A specific analysis of the content and form of the PST was also thoroughly performed considering the topic under study, the characteristics of scientific activities present in those texts, the language adopted, structure, and visual resources. This magazine addresses a wide range of topics, and most of them mention the construction of scientific knowledge and scientific culture. The language adopted in the majority of the PSCs is accessible to the general public since the authors use tools such as analogy and metaphors in an attempt to facilitate the understanding of the texts. In the O Leitor Pergunta section, all texts are considered medium-size texts (270-600 words), while in Mundo de Ciência section, the texts are small (less than 270 words) and large (more than 600 words). Both sections provide integrated reading since only a very few PST include disconnected parts from the main text. There are similarities between the texts of the two sections with spect to the use of visual resources, which include everything from photos to diagrams. Therefore, it was concluded that the use of PSCs is highly recommended in chemistry teaching since they offer students an opportunity for a stimulating and interesting reading (most texts are medium sized and address a variety of topics in accessible language) with aspects related to the nature of science. Moreover, the articles studied are related to concepts of Science-Technology-Society. The results of the teaching strategy proposed corroborate the points made earlier. This teaching strategy was well received by students and provided them with a better understanding of the nature of science and topics addressed in the classroom through the reading and discussion of the PST.