J
Joaquim A. Nóbrega
Researcher at Federal University of São Carlos
Publications - 319
Citations - 7499
Joaquim A. Nóbrega is an academic researcher from Federal University of São Carlos. The author has contributed to research in topics: Inductively coupled plasma & Inductively coupled plasma mass spectrometry. The author has an hindex of 41, co-authored 313 publications receiving 6798 citations. Previous affiliations of Joaquim A. Nóbrega include Federal University of São Paulo & Universidade Federal de Santa Maria.
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Journal ArticleDOI
Equilibrium studies for the sorption of chromium and nickel from aqueous solutions using raw rice bran
TL;DR: In this article, the capacity of raw rice bran for chromium and nickel removal from aqueous solutions was investigated using the Langmuir and Freundlich adsorption models, which are in common use for describing sorption equilibrium for wastewater treatment applications.
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Effect of acid concentration on closed-vessel microwave-assisted digestion of plant materials
Geórgia C. L. Araújo,Geórgia C. L. Araújo,Mario H. Gonzalez,Mario H. Gonzalez,Antonio G. Ferreira,Ana Rita A. Nogueira,Joaquim A. Nóbrega +6 more
TL;DR: The efficiency of microwave-assisted acid digestion of plants using different concentrations of nitric acid with hydrogen peroxide (30% v/v) was evaluated by measuring the residual carbon content (RCC) using inductively coupled plasma optical emission spectrometry (ICP-OES) with axial viewing as mentioned in this paper.
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Determination of residual carbon by inductively-coupled plasma optical emission spectrometry with axial and radial view configurations
Sandro T. Gouveia,Fernando V. Silva,Fernando V. Silva,Letícia M. Costa,Ana Rita A. Nogueira,Joaquim A. Nóbrega +5 more
TL;DR: In this paper, the authors evaluated axial and radial configurations of ICP-OESs for residual carbon content (RCC) determination and found that axial-view ICP was 20 times better than radial-view OES based on the slopes of the analytical curves at the most sensitive wavelength.
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Sample preparation in alkaline media
Joaquim A. Nóbrega,M.C. Santos,Rafael Arromba de Sousa,Solange Cadore,Ramon M. Barnes,Mark E. Tatro +5 more
TL;DR: The use of tetramethylammonium hydroxide, tertiary amines and strongly alkaline reagents for sample treatment involving extraction and digestion procedures is discussed in this paper.
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Comparison of heating extraction procedures for Al, Ca, Mg, and Mn in tea samples.
TL;DR: Large variations in the trace-element composition of teas were observed; these results are discussed with reference to both extraction media and type of tea.