Zobrazeno 1 - 6
of 6
pro vyhledávání: '"Andre Fernando Oliveira"'
Publikováno v:
Orbital: The Electronic Journal of Chemistry, Vol 12, Iss 2, Pp 105-107 (2020)
This paper is about a typical mistake in the calculation of standard deviation of measurements in cases in which there are no differences among repetitious replicates. Some students believe the standard deviation in those case is equal to zero. So, t
Externí odkaz:
https://doaj.org/article/bfd18be52fcf4adf954dabfeb9cef7d8
Autor:
André Fernando Oliveira, Renata Lopes Pereira, Marcos Flores Jr, Antônio Augusto Neves, Maria Eliana Lopes Ribeiro Queiroz
Publikováno v:
The Journal of Engineering and Exact Sciences, Vol 5, Iss 1, Pp 0020-0025 (2019)
The development of studies of Chemical solutions occurred with two distinct concepts, the XIX century concept, and the XX century concept. XIX century concept was created before the Arrhenius’ electrolytic theory and it did not consider the real ch
Externí odkaz:
https://doaj.org/article/30196f3ef5eb42bf977f2ad156d3eb9f
DEVELOPMENT OF A METHOD FOR THE DETERMINATION OF AMOXICILLIN IN CAPSULES BY POTENTIOMETRIC TITRATION
Autor:
Jean Castro Cruz, Mayra Aparecida Nascimento, Aline Maria Teixeira, André Fernando Oliveira, Renata Pereira Lopes
Publikováno v:
The Journal of Engineering and Exact Sciences, Vol 4, Iss 2, Pp 0234-0239 (2018)
This work presents the determination of amoxicillin (H3Amox+) in capsules by potentiometric titration. An optimized method was done with a standard amoxicillin solution that was title with NaOH solution. The initial pH was 4.35. As expected, the firs
Externí odkaz:
https://doaj.org/article/c23c5f2128f343b389d3941e3ed827b5
Autor:
André Fernando Oliveira, Alexandre Correa Lima, Astréa F. Souza Silva, Rodrigo de Maio Almeida
Publikováno v:
Química Nova, Vol 33, Iss 3, Pp 721-724 (2010)
TitDrop II, a practice low-cost titrator based on drop counting is proposed. A microcomputer counts drops in an opto-switch and it receives pH values from a commercial pHmeter with RS-232 serial port. The volume of drops must kept constant and the am
Externí odkaz:
https://doaj.org/article/ce609ef5f3f74151920e8420b52a9224
Autor:
Mônica Winkler de Oliveira, Alexandre W. S. Hilsdorf, Astréa F. de Souza Silva, André Fernando Oliveira
Publikováno v:
Química Nova, Vol 32, Iss 5, Pp 1134-1138 (2009)
The adsorption of ethidium bromide on XAD-7 resin was studied. The Freundlich model was the most representative isotherm model to describe the sorption behavior. A solid-liquid equilibrium model was proposed to explain the resin mass influence on the
Externí odkaz:
https://doaj.org/article/b1ebd881f9a141e5ba5fc288a909c582
Publikováno v:
Química Nova, Vol 30, Iss 1, Pp 224-228 (2007)
The aim of this paper is to present a simple way of treating the general equation for acid-base titrations based on the concept of degree of dissociation, and to propose a new spreadsheet approach for simulating the titration of mixtures of polyproti
Externí odkaz:
https://doaj.org/article/1818b0a4b78a4911acd8f7103260196c