8 documents found, page 1 of 1
EXPERIMENTO COM ABACATE, BORRA DE CAFÉ, LICURI E LEITE DE COCO PARA EXTRAÇÃO DE...
Cunha,Silvio; Rodrigues,Marina Costa; Mattos,Rosiene Reis; Teixeira,Leonardo Sena Gomes; Santos,Airam Oliveira; Santos,Elaine V.; Souza,Rauan S.An undergraduate organic chemistry experiment for oil extraction and biodiesel production using alternative biomass was developed, whereby oils of avocado, coconut and spent coffee grounds were obtained and submitted to transesterification reaction with CH3OH under NaOH catalysis. Avocado and coffee oils were obtained by typical extraction and coconut oil was obtained through water evaporation of coconut milk i...
Iodine nutritional status in Brazil: a meta-analysis of all studies performed i...
Campos,Renata de Oliveira; Barreto,Iasmin dos Santos; Maia,Lorena Rejane de Jesus; Rebouças,Sara Cristina Lima; Cerqueira,Taíse Lima de OliveiraObjectives Iodine deficiency disorder (IDD) is the result of an inadequate dietary intake of iodine, which physiological consequences are endemic goiter and thyroid dysfunction. The objective of this study was to a analyze studies that assessed the status of Brazil’s population iodine nutrition and IDD prevalence. Materials and methods Systematic review using PRISMA statement. Electronic database: PubMed, Medli...
A utilização de etanol em célula a combustível de óxido sólido
Fiuza,Raigenis da Paz; Silva,Marcos Aurélio da; Pontes,Luiz Antônio Magalhães; Teixeira,Leonardo Sena Gomes; Boaventura,Jaime SoaresThis work reports a review on the status and technical feasibility of the application of ethanol as fuel for Solid Oxide Fuel Cells (SOFC), presenting both external reform and cell with direct utilization of ethanol. Based on this survey, both experimental results and mathematical modeling indicated the technical feasibility of power generation by ethanol SOFC, with cell units producing 450 mW/cm², sufficient f...
Construção de uma cela de fluxo para medidas por espectrofotometria em fase sólida
Reis,Boaventura F.; Rocha,Fábio R. P.; Teixeira,Leonardo Sena Gomes; Costa,Antônio Celso Spinola; Korn,MauroA simple and low cost flow cell is proposed for measurements by solid-phase spectrophotometry employing a conventional spectrophotometer. The flow cell geometry allows the employment of a large amount of the solid support without causing both excessive attenuation of the radiation beam and increasing of the back-pressure. The adaptation of the flow cell in the optical path of the spectrophotometer in order to i...
Uso de irradiação de microondas na determinação espectrofotométrica de cromo co...
Costa,Antônio Celso Spínola; Assis,Júlio César Rosa; Torres,André Luís Carvalho; Ferreira,Sérgio Luís Costa; Korn,Maria das Graças AndradeCr(III) slowly forms a violet complex with EDTA at pH 2.5-5.0 under normal conditions. The complex formation can be accelerated by irradiating the reacting mixture with microwave energy. The complex Cr(III)-EDTA is completely formed within 3 minutes of microwave irradiation and followed by a simple and rapid method for spectrophotometric determination of chromium. The method may be successfully applied to deter...
Entendendo estrutura molecular com a molécula de hidrogênio ionizada
Moreno,Roberto Rivelino de Melo; Teixeira,Leonardo Sena GomesIn this paper a general view about the modern molecular structure theory is developed discussing the ionized hydrogen molecule. We introduce some necessary approximation methods for the electronic and nuclear spectra study adopting a systematic approach. In addition though, we have performed calculations in order to illustrate these methods.
Spectrophotometric determination of uranium using 2-(2- Thiazolylazo)-p-Cresol ...
Teixeira,Leonardo Sena Gomes; Costa,Antonio Celso Spínola; Ferreira,Sérgio Luís Costa; Freitas,Maria de Lourdes; Carvalho,Marcelo Souza deA sensitive and selective spectrophotometric method is proposed for the rapid determination of uranium using 2-(2- Thiazolylazo)-p-Cresol (TAC). The reaction between TAC and uranium (VI) is instantaneous at pH 6.5 and the absorbance remains stable for over 3 h. N-cetyl-N,N,N-trimethylamonium bromide (CTAB) and triton X-100 are used for increasing the sensitivity and solubility of the system respectively. The me...
Spectrophotometric Determination of Zinc Using 7-(4-Nitrophenylazo)-8-Hydroxyqu...
Korn,Maria das Graças Andrade; Ferreira,Adriana Costa; Teixeira,Leonardo Sena Gomes; Costa,Antonio Celso SpínolaA sensitive and selective spectrophotometric method is proposed for the rapid determination of zinc(II) using an 8-hydroxyquinoline derivative, 7-(4-nitrophenylazo)-8-hydroxyquinoline-5-sulfonic acid (p-NIAZOXS), as a new spectrophotometric reagent. The reaction between the p-NIAZOXS and zinc(II) is instantaneous at pH 9.2 (borax buffer) and the absorbance remains stable for over 24 h. The method allows the det...