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| Li,Cuilan; Gao,Shuqing; Gao,Qiang; Wang,Lichun; Zhang,Jinjing. |
| Humic substances are the major components of soil organic matter. Among the three humic substance components (humic acid, fulvic acid, and humin), humin is the most insoluble in aqueous solution at any pH value and, in turn, the least understood. Humin has poor solubility mainly because it is tightly bonded to inorganic soil colloids. By breaking the linkage between humin and inorganic soil colloids using inorganic or organic solvents, bulk humin can be partially soluble in alkali, enabling a better understanding of the structure and properties of humin. However, the structural relationship between bulk humin and its alkaline-soluble (AS) and alkaline-insoluble (AIS) fractions is still unknown. In this study, we isolated bulk humin from two soils of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil humic substances; Humin fractionation; Elemental composition; 13C NMR. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000100120 |
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| Santos,Éder José dos; Oliveira Junior,Dasio Roberto de; Hermann,Amanda Beatriz; Sturgeon,Ralph Edward. |
| ABSTRACT Twenty-seven bottled mineral waters from local markets in Curitiba, State of Paraná, Brazil were analyzed for a number of constituents, including: pH, conductivity, total dissolved solids, hardness, HCO3 - and CO 3 2-, as well as Ca2+, Mg2+, Na+, K+, NH4 + , F-, Cl-, NO3 -, NO2 - and SO4 2- by ion chromatography (IC); Al, Ba, Cd, Cr, Cu, Fe, Li, Mn, Ni, Sr, V and Zn by inductively coupled plasma optical emission spectrometry (ICP OES); Hg by cold vapor generation-ICP OES and As, Pb, Sb and Se by ICP-mass spectrometry (ICP-MS). The obtained limits of quantitation (LOQ) were adequate for the determination of all analytes using the various analytical techniques. Results for the analysis of AccuStandard certified reference materials QCS-01-5,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bottled mineral waters; Elemental composition; Chemical quality; Principal component analysis. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000100513 |
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