986 resultados para Diamond (automerkki)


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A simple and reliable voltammetric method is presented for the determination of amitriptyline using a boron-doped diamond electrode in 0.1 mol L-1 sulfuric acid solution as the support electrolyte. Under optimized differential pulse voltammetry conditions (modulation time 5 ms, scan rate 70 mV s-1, and pulse amplitude 120 mV), the electrode provides linear responses to amitriptyline in the concentration range 1.05 to 92.60 µmol L-1 and at a detection limit of 0.52 µmol L-1. The proposed method was successfully applied in pharmaceutical formulations, with results similar to those obtained using UV-vis spectrophotometric method as reference (at 95% confidence level), as recommended by the Brazilian Pharmacopoeia.

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Electrodegradation of atrazine in water was performed using homemade (PA and PB) and purchased (PC) boron-doped diamond anodes. The degradation was monitored off-line by analyzing total organic carbon and high performance liquid chromatography with diode array detector (HPLC-DAD) and at-line by UV spectroscopy. The spectra were recorded every 2 min. The rank deficiency problem was resolved by assembling an augmented column-wise matrix. HPLC was employed to separate the original and byproducts degradation components. Aiming the same goal, multivariate curve resolution - alternating least squares (MCR-ALS) was applied to resolve the UV spectroscopic data. Comparison between HPLC and MCR-ALS separations is presented. By using MCR-ALS the spectra of atrazine and two byproducts were successfully resolved and the resulted concentration profiles properly represented the system studied. The ALS explained variance (R2) for PA, PB and PC was equal to 99.99% for all of them and the lack of fit for PA, PB and PC were 0.39, 0.34 and 0.54 respectively. The correlation (R) between the recovered and pure spectra were calculate for each electrodegradation, validating the MCR-ALS results. The average R was equal to 0.997. The spectral and concentration profiles described with this new approach are in agreement with HPLC-DAD results. The proposed method is an alternative to classical analyses for monitoring of the degradation process, mainly due to the simplicity, fast results and economy.

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Optimization of the main parameters of SWASV using boron-doped diamond electrode was described for the simultaneous determination of Zn, Cd, Pb and Cu free in coconut water. The values of electroanalytical parameters studied were optimized with the factorial design and center composite design. The optimized parameters for the preconcentration of metals were -1.50 V for potential, and 240 s for deposition time. For SWV, the optimized value was 11.56 mV for step potential. In addition, frequency and pulse height were defined at 100 Hz and 55 mV, respectively. Furthermore, the concentration of the supporting electrolyte (acetate buffer, pH 4.7) was optimized in 0.206 mol L-1. The optimized procedure was applied in two samples of coconut water: natural and processed. The limits of detection (LOD) obtained for Zn, Cd, Pb and Cu were 7.2; 4.4; 3.3 and 1.5 µg L-1, respectively. The concentrations of Cd and Pb were not detected. On the other hand, the values found for the concentrations of Zn and Cu were: < LOD (29 µg L-1) and (6.8 ± 0.9) µg L-1 for the natural sample; and (85.8 ± 4.2) µg L-1 and (7.7 ± 0.6) µg L-1 for the processed sample, respectively.

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Tässä diplomityössä tarkastellaan HelenEngineeringin energiantuotantolaitosprojektien koneteknisten tietojen hallintaa. Työn tavoitteena oli muodostaa HelenEngineeringin energiantuotantolaitosprojektien koneteknisten tietojen hallinnankehittämisehdotuksia, joilla pyritään kehittämään koneteknisten tietojen hallintaa vastaamaan energiantuotantolaitoksen elinkaarinäkökulmasta asetettuja laatu- ja aikatauluvaatimuksia. Kehittämisehdotuksia on muodostettu koneteknisten tietojen laadunhallintaan ja käsittelyyn liittyen. Ne koskevat toimintatapoja, hallintajärjestelmiä ja niiden käyttöön tarvittavaa osaamista. Esitetyt kehittämisehdotukset perustuvat HelenEngineeringin projektien koneteknisten tietojen hallinnasta tunnistettuihin kehittämiskohtiin. Diplomityössä on muodostettu menetelmä näiden kehittämiskohtien tunnistamiseksi. Tämä menetelmä perustuu organisaation tietojen hallinnan suunnittelussa käytettävään timanttimalliin. Timanttimalli on esitelty tämän diplomityön teoriaosuudessa. Kehittämiskohtien tunnistamiseksi HelenEngineeringin energiantuotantolaitosprojektien koneteknisten tietojen hallintaprosessit on kuvattu. Lisäksi kehittämiskohtien tunnistamista varten on kerätty tarvittavia tietoja haastattelemalla asiantuntijoita.

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Objetivo: comparar o grau de aderências no ovário de acordo com diferentes tipos de fechamento do córtex ovariano. Métodos: quinze coelhos foram distribuídos aleatoriamente em três grupos, de acordo com o tipo de fechamento do córtex ovariano, sendo utilizados a diatermia bipolar, a poliglactina 910 5-0 e o categute simples 5-0. Após 2 semanas os animais foram sacrificados e o grau de aderências do ovário direito foi avaliado segundo a classificação de Diamond. O ovário esquerdo, não incisado, serviu de controle. Na análise estatística foram empregados a análise de variância (ANOVA), o teste de Scheffé e o teste t de Student. Resultados: as médias dos escores de aderência para o grupo bipolar, poliglactina e categute simples foram 0,7, 1,5 e 2,0, respectivamente. A análise de variância detectou diferença significativa (p=0,02) entre os três grupos. Usando-se o teste de Scheffé para a comparação dos grupos dois a dois, encontrou-se uma diferença significativa apenas entre o grupo bipolar e o grupo do categute simples. Comparando-se o grupo em que se usaram suturas (independente do material empregado) com o grupo bipolar verificou-se uma diferença estatisticamente significativa (p=0,01) entre as médias dos escores de aderência do ovário direito (1,8 e 0,7, respectivamente). Conclusões: os resultados obtidos no presente estudo estão de acordo com os dados da literatura, indicando que o fechamento por segunda intenção do córtex ovariano é mais vantajoso, em relação à formação de aderências, que o fechamento com o uso de suturas.

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17 x 24 cm

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22 x 27 cm

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kuv., 14 x 20 cm

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kuv., 10 x 19 cm

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9 x 16 cm

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kuv., 9 x 15 cm

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kuv., 9 x 15 cm

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kuv., 9 x 17 cm

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kuv., 9 x 17 cm