Encontrados 3 documentos, a visualizar página 1 de 1
Determination of nitrate and nitrite in dairy samples by sequential injection u...
Lima, M.J. Reis; Fernandes, Sílvia M.V.; Rangel, António O.S.S.A sequential injection analysis (SIA) system for the spectrophotometric determination of nitrate in dairy samples was developed. A test portion was aspirated into a carrier solution containing ethylendiaminetetracetic acid (EDTA) and ammonium buffer, which flowed into a copperized cadmium reduction column installed in-line for the determination of the nitrate plus nitrite contents of samples. For the nitrite de...
A new approach for the sequential injection spectrophotometric determination of...
Lima, M. J. Reis; Tóth, Ildikó V.; Rangel, António O. S. S.A sequential injection system based on the ABTS (2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic-acid) methodology was developed. The proposed method, incorporating a mixing chamber in the side port of the selection valve, was evaluated to measure the total antioxidant activity of several beverages and foods. The ABTS•+ is generated by oxidation of ABTS with potassium persulfate and is reduced in presence of...
Sequential injection titration of chloride in milk with potentiometric detection
Lima, M.J. Reis; Fernandes, Sílvia M.V.; Rangel, António O.S.S.In this work, a sequential injection system for the pseudo-titration of chloride in milk is described. Milk was directly aspirated into the system and sandwiched between two silver nitrate plugs (titrant). The aspirated zones were then propelled to the detector (Ag2S/Ag tubular electrode), where the depletion in the titrant silver concentration (due to the formation of a AgCl precipitate) was monitored. The res...
| Financiadores do RCAAP | |||||||
|
|
|
|
|
|
||