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Complexos de cobre (II) com bases de Schiff tridentadas, tipo ONN e tetradentadas simétricas e assimétricas, tipo ONNO: síntese e caracterização e estudos como catalisadores na oxidação de catecóis
(Universidade Federal de São Carlos, 2011-03-23) Paulo, Luciana Batista de; Dockal, Edward Ralph; https://lattes.cnpq.br/6461328124491559; https://lattes.cnpq.br/8882360987934876
Salen-type complexes are an important class of coordination compounds and are used as catalysts in various homogeneous and heterogeneous systems. Complexes of transition metals participate in many chemical processes, which make the study of these complexes very interesting. Research shows that the complexes of salen [salen = N, N'-ethylenebis (salicilidenoamina)] are efficient catalysts. Some compounds of this type have been investigated as catalysts for the oxidation of catechol. In this work three types of compounds the tetradentate ligands and symmetrical complexes, tridentate complexes and the asymmetric tetradentate complex, were synthesized. The series provided satisfactory yields. The compounds synthesized in this work were characterized by melting point, elemental analysis, vibrational spectroscopy in the IR region, absorption spectra in the UV-vis, conductivity measurements and solubility. The ligands were also characterized by nuclear magnetic resonance. From these characterizations, comparisons were made with respect to the effects of the substituents on the aromatic ring within the same series of compounds and also compared the results obtained for different lines of work. The kinetics was performed using a spectrophotometer, following the formation of the product derived from oxidation of 3,5-di-tert-butylcatechol at 400 nm. Among the complexes showed catalytic activity are the symmetrical complex [Cu (salen)], kcat = 2.6 x10-2 s-1, Vmax = 1.74 x10-7 mol L-1 s-1 and the complex asymmetric [Cu (3.5 Brsalen)]ass, kcat = 4.1 x10-2s-1, Vmax = 2.72 x10-7 mol L-1 s-1 and [Cu (3.5 Br4MeO-3, 5Br'salen) ]ass, kcat = 5.2 x10-2 s-1, Vmax = 3.39 x10-7 mol L-1 s-1.
Leis de conservacão escalar: fórmula explícita e unicidade
(Universidade Federal de São Carlos, 2011-03-23) Rossini, Alex Ferreira; Kondo, Cezar Issao; https://lattes.cnpq.br/0900348462714778; https://lattes.cnpq.br/3442840719931515
We study scalar conservation laws, with the deduction of an explicit formula of a smooth solution with compact support, we also present the behavior of the solution given by the formula when the initial value is zero outside a finite interval. In order to study the uniqueness of a given conservation law under certain hypotheses.
Estudo de influência de cobertura plástica na remoção de água de lodos de estações de tratamento de água em leitos de drenagem
(Universidade Federal de São Carlos, 2011-03-23) Reis, Renan Felicio dos; Cordeiro, João Sergio; https://lattes.cnpq.br/2572864522562875; https://lattes.cnpq.br/1840510720475585
Most of Water Treatment Plant (WTP) for public supply in Brazil use surface water as source and conventional complete cycle as treatment system. In this type of treatment wastewater are restrained/generated which vary mainly according to the type and amount of chemical added and the characteristics of the water resource. This wastewater is found mainly in clarifiers (sludge) and backwash water filter (BWF) from WTP. Unfortunately, most of Brazilian WTP launches its waste directly into water resources, violating Brazilian Law 9605 published in 1998. There are mechanical and natural technologies for water removal from wastewater restrained during the treatment. Once known that wastewater from WTP has fluid characteristic, some technologies to remove its water have been developed. A natural one is the drainage bed, developed and proposed by Cordeiro (2001). The drainage bed has basically two stages: drainage and evaporation. This dissertation presents results of a study, whose centre objective was to achieve improvements in water sludge removal restrained in clarifiers by the use of plastic cover (evaporation stage). Results of effective tests in prototypes located in Sao Carlos WTP (Sao Paulo State) with plastic cover have showed that this roof (commercial reference PVC 0.30 milimeters) uses has accelerated the evaporation process, and has protected sludge from rain. The height of the roof that presented the best result was 0.20 meters in relation to the board of prototype, realizing to obtain a sludge 56% dryer than in tests without the roof. Preliminary tests in laboratory scale generated a promising scenario for the use of cationic polymer in large scale doubling the efficiency of the initial drainage of sludge. However, other laboratory tests with different characteristics of geotextile blanket only confirmed the superiority of using woven blanket type with surface density of 600 g/m² (which had already been used in other studies), compared to the others, in reference to obtain better efficiency at the initial drainage of water present in raw sludge.
Fronteiras da "ilegalidade": migrações não documentadas de Governador Valadares
(Universidade Federal de São Carlos, 2011-03-23) Yamauie, Thaisa Lumie; Lanna, Marcos Pazzanese Duarte; https://lattes.cnpq.br/8355559441138016; https://lattes.cnpq.br/2147894099585401