941 resultados para Rotating disk electrodes
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
The presence of contaminants, such as phosphate, in biodiesel, has several drawbacks for instance: current engines perform poorly, fuel tanks deteriorate, catalytic conversion is damaged, and particles emission is increased. Therefore, biodiesel quality control is extremely important for biodiesel acceptance and commercialization worldwide. In this context, a bare glassy carbon electrode (GCE) and another chemically modified electrode with iron hexacyanoferrate (Prussian Blue – PB) were developed for determination of phosphate in biodiesel. The LODs of 6.44 and 1.19 mg kg−1, and LOQs of 21.43 and 3.97 mg kg−1 were obtained for the bare GCE and the PB-modified GCE, respectively. The methodology was employed for analysis of Brazilian biodiesel samples, and it led to satisfactory results, demonstrating its potential application for biodiesel quality control. Additionally, recovery and interference tests were conducted, which revealed that the developed methods are suitable for analysis of phosphate in biodiesel samples.
Resumo:
We consider an electric charge rotating around a Schwarzschild black hole. We compute, using quantum field theory in curved spacetime at the tree level, the power emitted by the rotating charge minimally coupled to the Maxwell field. We also compute how much of the radiation emitted by the swirling charge is absorbed by the black hole.
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Pós-graduação em Química - IQ
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
With the fast growth of cancer research, new analytical methods are needed to measure anticancer drugs. This is usually accomplished by using sophisticated analytical instruments. Biosensors are attractive candidates for measuring anticancer drugs, but currently few biosensors can achieve this goal. In particular, it is challenging to have a general method to monitor various types of anticancer drugs with different structures. In this work, a biosensor was developed to detect anticancer drugs by modifying carbon paste electrodes with glutathione-s-transferase (GST) enzymes. GST is widely studied in the metabolism of xenobiotics and is a major contributing factor in resistance to anticancer drugs. The measurement of anticancer drugs is based on competition between 1-chloro-2,4-dinitrobenzene (CDNB) and the drugs for the GST enzyme in the electrochemical potential at 0.1 V vs. Ag/AgCl by square wave voltammetry (SWV) or using a colorimetric method. The sensor shows a detection limit of 8.8 mu M cisplatin and exhibits relatively long life time in daily measurements. (C) 2014 Elsevier B.V. All rights reserved.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)