Extractability of dioxins from soil: I. Extractability of dioxins from airborne particulates and humic acid fraction in soil

2005 ◽  
Vol 85 (8) ◽  
pp. 503-514 ◽  
Author(s):  
Hiroaki Otaka ◽  
Miho Shinomiya ◽  
Takashi Amagai
Keyword(s):  
Humic Acid ◽  
Acid Fraction ◽  
Airborne Particulates

HUMUS FRACTION RATIOS AS A MEANS OF DISCRIMINATING BETWEEN HORIZON TYPES

1980 ◽  
Vol 60 (2) ◽  
pp. 219-229 ◽  
Author(s):  
L. E. LOWE
Keyword(s):  
Organic Matter ◽  
Humic Acid ◽  
Carbon Content ◽  
Fulvic Acid ◽  
Soil Classification ◽  
Acid Fraction ◽  
Humus Fraction ◽  
Wide Range ◽  
Fraction Distribution

Humus fraction distribution in a wide range of horizon samples was examined by measuring carbon content in humic acid (Ch), in fulvic acid (Cf) and in the strongly colored polyphenolic component of the fulvic acid fraction (Ca). Fraction distribution was described by the ratios Ch/Cf and Ca/Cf. It was concluded that humus fraction ratios were related to horizon types as used in the Canadian System of Soil Classification, and were effective in discriminating between certain horizon types, particularly between Luvisolic Bt and Podzolic Bf. The results also suggested that humus fraction ratios may be effective in separating distinct sub-populations within Ah horizons and Bf horizons in general, based on qualitative differences in organic matter present. Aspects of the role of humus fractions in soil genesis are discussed.

Assessment of clay mineral selectivity for adsorption of aliphatic/aromatic humic acid fraction

2019 ◽  
Vol 511 ◽  
pp. 21-27 ◽  
Author(s):  
Mohamed E.A. El-sayed ◽  
Moustafa M.R. Khalaf ◽  
Dennis Gibson ◽  
James A. Rice
Keyword(s):  
Humic Acid ◽  
Clay Mineral ◽  
Acid Fraction

scholarly journals Characterization of Ultrafiltration-Fractionated Humic Acid Derived from Chinese Weathered Coal by Spectroscopic Techniques

Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2030
Author(s):  
Shuiqin Zhang ◽  
Liang Yuan ◽  
Yanting Li ◽  
Bingqiang Zhao
Keyword(s):  
Molecular Weight ◽  
Humic Acid ◽  
Atomic Ratio ◽  
Raw Material ◽  
Spectroscopic Techniques ◽  
Acid Fraction ◽  
Aromatic Rings ◽  
Xps Spectra ◽  
Weathered Coal ◽  
Degree Of Aromaticity

Weathered coal is a widely used raw material of farm-oriented humic acid in China, while the high heterogeneity impedes its sufficient utilization. In this study, we fractionated the humic acid derived from Chinese weathered coal by ultrafiltration, and three fractions with the molecular range of ≥100 kDa, 10–100 kDa, ≤10 kDa were obtained. Subsequently, the chemical and spectral properties of the fractions were characterized by elemental analysis, potentiometric titration, Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and X-ray photoelectron (XPS) and other spectroscopy. The results showed that more than 60% of humic acid by weight was concentrated in the molecular range higher than 100 kDa, while only 3.25% was assigned to that with molecular weight lower than 10 kDa. The humic acid fraction with molecular weight higher than 100 kDa showed more carbon content, lower H/C atomic ratio, while higher E4/E6 ratio, more aromatic structure in FTIR, 13C NMR, and XPS spectra, indicating a higher degree of aromaticity and stronger hydrophobicity. Conversely, there were more carboxyl groups and aliphatic structures, while fewer condensed aromatic rings for the humic acid fraction with molecular weight less than 100 kDa. These differences provide a baseline for the better utilization of weathered coal.

HUMIC ACID ASSOCIATED PHOSPHORUS IN SOME SOILS OF ALBERTA

1963 ◽  
Vol 43 (2) ◽  
pp. 235-241 ◽  
Author(s):  
J. F. Dormaar
Keyword(s):  
Organic Matter ◽  
Humic Acid ◽  
Electrophoretic Mobility ◽  
Organic Phosphorus ◽  
Paper Electrophoresis ◽  
Acid Fraction ◽  
Soil Group ◽  
Soil Organic Phosphorus ◽  
Electrophoresis Technique ◽  
Soil Groups

The association of phosphorus with the humic acid fraction of the organic matter of surface horizons of soils representing six soil zones of Alberta was investigated with the aid of paper-electrophoresis. In order to locate the humic acid phosphates following separation, several techniques were combined and modified.The application of the electrophoresis technique proved to be useful in the study of soil organic phosphorus. It seems that the humic acid phosphates from the various soils can be arranged into three groups of increasing complexity and electrophoretic mobility. The humic acid associated phosphorus from members of the Brown and Dark Brown Great Soil Groups showed low electrophoretic mobility and seemed rather uncomplicated, while the greatest variation was found in the humic acid fraction of the member from the Grey Wooded Great Soil Group.

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