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Construção e aplicação analítica de eletrodos de pasta de carbono modificada com ftalocianina de cobalto para determinação de analítos de interesse
(Universidade Federal de São Carlos, 2004-04-16) Conceição, Cleone das Dores Campos; Fatibello Filho, Orlando; https://lattes.cnpq.br/9859737944357808
In this thesis work the development and applications of cobalt phthalocyanine carbon paste electrode (CoPc/CPE) for voltammetric determination (cyclic voltammetry and differential pulse voltammetry) of hydrazine in boiler feed water, dopamine, vitamin B1 (thiamine) and vitamin B6 (pyridoxine) in pharmaceutical preparations available commercially in the market, without any previous treatment of the samples. The CoPc/CPE presented voltammetric response (for cyclic voltammetry and differential pulse voltammetry) linear in the hydrazine concentration range from 1,3x10-4 to 9,8x10-4 mol L-1, with detection limit of 3,0x10-5 mol L-1 and 5,0x10-5 to 7,4x10-4 mol L-1, with detection limit of 2,3x10-5 mol L-5, respectively. The hydrazine quantification in waters of boilers using CoPc/CPE presented results of agreement with the spectrophotometric method with an interval of acceptable relative error. The CoPc/CPE presented a voltammetric response (for cyclic voltammetry and differential pulse voltammetry) linear in the dopamine concentration range from 1,3x10-5 to 2,8x10-4 mol L-1, with detection limit of 1,0x10-5 mol L-1e 5,0x10-6 to 9,8x10-5 mol L-1, with limit of detection of 1,4x10-6 mol L-1, respectively. That modified electrode presented good performance as voltammetric sensor in the dopamina determination in pharmaceutical preparations. The CoPc/CPE presented an voltammetric response (differential pulse voltammetry) linear in the vitamin B1 (thiamine) concentration range from 5,0x10-5 to 3,8x10-4 mol L-1, with detection limit of 2,5x10-5 mol L-1. The thiamine quantification in pharmaceutical formulations using CoPc/CPE presented results of agreement with the spectrofluorimetric method of Brazilian Pharmacopeia s with an interval of acceptable relative error. CoPc/CPE presented an voltammetric response (for cyclic voltammetry and differential pulse voltammetry) linear in the vitamin B6 (pyridoxine) concentration range from 5,0x10-5 to 9,8x10-4 mol L-1, with detection limit of 4,7x10-6 mol L-1 and 5,0x10-5 to 3,4x10-4 mol L-1, with detection limit of 1,3x10-6 mol L-1, respectively. That modified electrode presented good performance as voltammetric sensor in the pyridoxine determination in pharmaceutical preparations. The CoPc/CPE was also used in the simultaneous determination of vitamins B1 (thiamine) and B6 (pyridoxine) by differential pulse voltammetry, in pharmaceutical preparations, once the oxidation peaks potentials of the vitamin B1 (-0,13 V) and vitamin B6 (0,55V), healthy very different. The analytic curves were linear in the interval of thiamine concentration of 1,9x10-4 to 7,4x10-4 mol L-1, with limit of detection of 8,4x10-5 mol L-1 and of 1,0x10-4 to 7,4x10-4 mol L-1, with limit of detection of 1,5x10-5 mol L-1 for pyridoxine. That modified electrode presented satisfactory acting as voltammetric in the determination of both in pharmaceutical preparations.
Variação temporal e espacial da composição da ictiofauna demersal do infralitoral roso da baía de Paranaguá, PR, Brasil - 2004
(Universidade Federal de São Carlos, 2004-04-16) Nakayama, Paula; Peret, Alberto Carvalho; https://lattes.cnpq.br/0995579236780271
The ichthyofauna of Paranagua bay infralittoral was studied from samples obtained from five sampling points, respectively in front of Gamboa dos Papagaios, Gamboa do Sucuriu, Gamboa do Baguaçu, Planície da Ponta do Poço and Praia do Pontal do SuI. The samples were collected monthly, from October 1999 to September 2000, with a trawl net. As a result, 6633 individuals, from 55 species and 27 families were captured, and the madamango sea catfish (bagre) Cathorops spixxi was the most abundant element with 21% of the total number. During the sample collection, the most important variable for the distribution of months was the temperature, which allowed the division of the sampling period into hot and cold months. A detected variation in groupings reflected the temporal oscillation of the ichthyofauna composition, and the variation in dissimilarity between sampling points occurred due to the differences in abundance and richness of the captured species. The highest percentages of dissimilarity between sampling points were observed during the hot months, and the high frequencies of Anisotremus surinamensis, Etropus crossotus, Genidens genidens, Micropogonias fumieri, and Sphoeroides greeleyi were also related to high temperatures. Since a great number of species present a more intense reproductive activity during high temperature periods, and some marine species use the estuary as a rearing ground, a higher number and richness of fishes could be observed during the hot months. Finally, the analysis of the ichthyofauna space variation showed differences in composition and abundance of fish communities from the studied areas. These space differences are probably related to the complexity of the habitats, which is caused by the different bottom covers found at the sampling points.
Ecologia e conservação de catetos, Tayassu tajacu (Linnaeus, 1758) (Artiodactyla, Tayassuidae) em áreas de Cerrado do Estado de São Paulo
(Universidade Federal de São Carlos, 2004-04-16) Neri, Fernanda Maria; Pires, José Salatiel Rodrigues; https://lattes.cnpq.br/3412204514901170; https://lattes.cnpq.br/7136806982117865
Among the present mammals in the units of conservation Estação Ecológica de Jataí (EEJ) and Parque Estadual de Vassununga (PEV) and in the unit of production, Estação Experimental de Luiz Antônio (EELA), located in the northeast of the State of São Paulo, are the peccaries, Tayassu tajacu. Between March of 2000 and January of 2004, the home range of them, the use of the space, diet and the impacts on the populations in these areas were studied. For obtaining the data, the radiotelemetry technique was used as tool and methods of terrestrial tracking. Seven peccaries received radio-collars for monitoring. It was established four home ranges being three referring to each one of the peccaries of the Estação Ecológica de Jataí (EEJ) and Estação Experimental de Luiz Antônio with 161, 930 and 1.387 hectares and one regarding of the Parque Estadual de Vassununga (PEV), with 350 hectares. It were identified 22 species of plants used by the peccaries and 16 of wich were of confirmed use in the diet, five were considered as of probable use and one species was used as shelter. The diet also included ingested fruits of two palm trees (Família Arecaceae), other native species and five exotic species cultivated at orchards of EELA. It was identified some in this study factors that can be interfering negatively on the populations of peccaries and of other animals as weed killer application, hunts and activities of collection of exotic wood. Indirect impacts were also identified showing the need to improve the system of administration of units of conservation, including the definition of Management Plans that prioritize the regional biodiversity.