Threshold electrolyte concentration and dispersive potential in relation to CROSS in dispersive soils

Soil Research ◽  
2012 ◽  
Vol 50 (6) ◽  
pp. 473 ◽  
Author(s):  
Alla Marchuk ◽  
Pichu Rengasamy
Keyword(s):  
Organic Matter ◽  
Structural Integrity ◽  
Electrolyte Concentration ◽  
Clay Content ◽  
Exchangeable Cation ◽  
Soil Solutions ◽  
Highly Correlated ◽  
The Individual ◽  
Dispersive Soils ◽  
Cation Ratio

We have used the newly developed concept of CROSS (cation ratio of soil structural stability) instead of SAR (sodium adsorption ratio) in our study on dispersive soils. CROSS incorporates the differential dispersive powers of Na and K and the differences in the flocculating effects of Ca and Mg. The CROSS of the dispersed soil solutions, from the differently treated soils of three soil types varying in clay content, mineralogy, and organic matter, was highly correlated with the amount of clay dispersed. The relation between CROSS and exchangeable cation ratio depended on soil type, and particularly organic matter and the content and mineralogy of clay. Threshold electrolyte concentration of the flocculated suspensions was significantly correlated with CROSS of the dispersed suspensions. The cationic flocculating charge of the flocculated suspensions, which incorporates the individual flocculating powers of the cations, was significantly correlated with CROSS. However, these types of relations will depend on several soil factors even within a given soil class. Therefore, we have derived the dispersive potential of an individual soil from which we calculated the required cationic amendments to maintain flocculated soils and their structural integrity.

Comparison of three methods of measuring surface area of soils

1999 ◽  
Vol 79 (2) ◽  
pp. 345-351 ◽  
Author(s):  
E. de Jong
Keyword(s):  
Organic Matter ◽  
Surface Area ◽  
External Surface ◽  
Clay Mineralogy ◽  
Clay Content ◽  
Sorptive Capacity ◽  
Measuring Surface ◽  
Glycol Monoethyl Ether ◽  
Highly Correlated ◽  
The Impact

Surface area (SA) is an important property of soils, but different methods can give widely different estimates of SA, and of the contribution of organic matter to SA. This study was undertaken to compare two common methods of measuring SA (EGME [ethylene glycol monoethyl ether] and N2 sorption) with SA estimates using H2O sorption on selected Saskatchewan soils; some soils from Kenya were included to show the impact of clay mineralogy. For the Saskatchewan soils, the three estimates of SA were highly correlated to each other and to clay content, but SA EGME was 2 to 3 times SA H2O and 7 to 52 times SA N2. Organic matter did not appear to contribute to SA EGME, increased SA H2O and decreased SA N2. Clearly the three methods differ in their access to internal and external surface area and this should affect their utility as indices of the sorptive capacity of field soils. Key words: Surface area, EGME, N2 sorption, water sorption

The strength of remolded soils as affected by exchangeable cations and dispersible clay

Soil Research ◽  
1994 ◽  
Vol 32 (2) ◽  
pp. 185 ◽  
Author(s):  
AR Barzegar ◽  
RS Murray ◽  
GJ Churchman ◽  
P Rengasamy
Keyword(s):  
Tensile Strength ◽  
Clay Content ◽  
Exchangeable Cations ◽  
Rate Of Change ◽  
Exchangeable Cation ◽  
Regression Analyses ◽  
Exchangeable Sodium ◽  
Exchangeable Magnesium ◽  
Highly Correlated ◽  
Dispersible Clay

The tensile strengths of remoulded samples of five Australian soils with differing clay type, texture and shrink-swell potential were measured as a function of exchangeable cations (Na, Ca and Mg) and exchangeable sodium percentage (ESP). Spontaneously and mechanically dispersible clays were also determined as a function of ESP. The tensile strength changed with the nature of the exchangeable cation, clay content and amounts of spontaneously and mechanically dispersible clay. In Ca-soils, the tensile strength was highly correlated with clay content and CEC. Regression analyses of data for soils containing various amounts of exchangeable sodium showed that mechanically and spontaneously dispersible clay were individually correlated with the tensile strength of remoulded soils. However, multiple regression analyses of these data indicated that spontaneously dispersible clay alone was a major predictor of the tensile strength of remoulded sodic soils. This suggests that measurement of spontaneously dispersible clay adequately accounts for the differences in tensile strengths of dry remoulded soils as influenced by ESP values. Analysis of variance of data for all the soils with varying ESP values showed that spontaneously dispersible clay was strongly correlated with clay content. Analyses of data for individual soil type showed that spontaneously dispersible clay was highly correlated with ESP. For each soil studied, increase in ESP resulted in increase of dispersible clay and hence in tensile strength. Although tensile strength increased with ESP, the rate of change of strength with ESP was different for each soil. Soil with the highest clay content gave rise to the greatest rate of change. The effect of exchangeable magnesium on tensile strength was similar to calcium. However, in two of the soils, exchangeable magnesium, in the presence of sodium, increased the strength slightly more than calcium, confirming the ionic radius effect of these elements.

CATION EXCHANGE AND ASSOCIATED PROPERTIES OF SOME SOILS FROM VANCOUVER ISLAND, BRITISH COLUMBIA

1967 ◽  
Vol 47 (3) ◽  
pp. 187-202 ◽  
Author(s):  
J. S. Clark ◽  
A. J. Green ◽  
W. E. Nichol
Keyword(s):  
British Columbia ◽  
Organic Matter ◽  
Cation Exchange ◽  
Clay Content ◽  
Vancouver Island ◽  
Southeastern Part ◽  
Ph Dependent ◽  
High Base ◽  
Highly Correlated ◽  
Extractable Al

Studies of the cation exchange properties of the soils of Vancouver Island, British Columbia showed that, in general, the soils had high base saturation even though the precipitation was high. There was no consistent relation between the corrected lime potential values for the soils and the annual precipitation. The pH-dependent CEC values of the soils were highly correlated with organic matter and oxalate-extractable Al but poorer correlations were obtained with the clay content and oxalate-extractable Fe. The correlation between pH-dependent CEC and citrate-dithionite-extractable Fe was not significant. Complexes of Al with organic matter appeared to be the main source of the pH-dependent CEC in the soils.Soils from the drier southeastern part of the Island with fragipans had as low or lower corrected lime potential values in the upper part of the profile than did soils from the more humid and more densely forested parts of the Island. Although oxalate-extractable Al was accumulated in the upper solum of soils with fragipans there was no pronounced enrichment of either oxalate- or citrate-dithionite-extractable Fe. The corrected lime potential pattern and the free oxide distribution of the soils with fragipans differed from the soils without fragipans.

scholarly journals Adsorption of Fluometuron, Prometryne, Sencor, and 2,4-D by Soils

1969 ◽  
Vol 57 (4) ◽  
pp. 286-293 ◽  
Author(s):  
L. C. Liu ◽  
H. R. Cibes-Viadé
Keyword(s):  
Organic Matter ◽  
Cation Exchange ◽  
Adsorption Capacity ◽  
Cation Exchange Capacity ◽  
Organic Matter Content ◽  
Clay Content ◽  
Exchange Capacity ◽  
Matter Content ◽  
The Mean ◽  
Highly Correlated

The adsorption capacity of Fluometuron, Prometryne, Sencor, and 2,4-D by 48 local soils was determined spectrophotometrically. The mean adsorptivities of the four herbicides by these soils were as follows: Prometryne 37.0 percent, Sencor 23.0 percent, Fluometuron 22.6 percent, and 2,4-D 12.4 percent. The results indicated that organic matter content was the factor most highly correlated with adsorption of these herbicides by the 48 soils. Cation exchange capacity was found to correlate significantly with adsorption of Fluometuron, Prometryne, and Sencor. Such was not the case with 2,4-D. Correlation between clay content and adsorption of Fluometuron and Sencor was statistically significant. In contrast, no significant correlation was noted between clay content and adsorption of Prometryne and 2,4-D.

Phytotoxicity and Adsorption of Chlorsulfuron as Affected by Soil Properties

Weed Science ◽  
1985 ◽  
Vol 33 (4) ◽  
pp. 564-568 ◽  
Author(s):  
Wondimagegnehu Mersie ◽  
Chester L. Foy
Keyword(s):  
Organic Matter ◽  
Soil Ph ◽  
Chemical Properties ◽  
Clay Content ◽  
Physical And Chemical Properties ◽  
Highly Correlated ◽  
Relationship Of ◽  
Physical And Chemical ◽  
The Relationship ◽  
And Chemical Properties

The phytotoxicity of chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl] benzenesulfonamide} was compared in six soils, and the relationship of activity to soil physical and chemical properties was evaluated. The influence of soil pH (4.2 to 7.8) on phytotoxicity and adsorption of chlorsulfuron incorporated into high-organic-matter soil was also studied. For the phytotoxicity studies, corn (Zea maysL. ‘Pioneer 3320’) was used as the bioassay plant. Organic matter was the soil variable most highly correlated with chlorsulfuron phytotoxicity. There was an inverse relationship between phytotoxicity and organic matter. No significant relationship between clay content and chlorsulfuron toxicity was observed. The adsorption of chlorsulfuron decreased with increasing soil pH while desorption was greater at alkaline pH. Phytotoxicity of chlorsulfuron increased with increasing soil pH and reached a maximum at pH 6.9.

scholarly journals Enzyme-Loaded Flower-Shaped Nanomaterials: A Versatile Platform with Biosensing, Biocatalytic, and Environmental Promise

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1460
Author(s):  
Khadega A. Al-Maqdi ◽  
Muhammad Bilal ◽  
Ahmed Alzamly ◽  
Hafiz M. N. Iqbal ◽  
Iltaf Shah ◽  
...  
Keyword(s):  
Organic Matter ◽  
Metal Ions ◽  
Critical Points ◽  
Structural Integrity ◽  
Early Stage ◽  
Surface Orientation ◽  
Critical Factors ◽  
Inorganic Hybrid ◽  
Iron Based ◽  
Significant Attention

As a result of their unique structural and multifunctional characteristics, organic–inorganic hybrid nanoflowers (hNFs), a newly developed class of flower-like, well-structured and well-oriented materials has gained significant attention. The structural attributes along with the surface-engineered functional entities of hNFs, e.g., their size, shape, surface orientation, structural integrity, stability under reactive environments, enzyme stabilizing capability, and organic–inorganic ratio, all significantly contribute to and determine their applications. Although hNFs are still in their infancy and in the early stage of robust development, the recent hike in biotechnology at large and nanotechnology in particular is making hNFs a versatile platform for constructing enzyme-loaded/immobilized structures for different applications. For instance, detection- and sensing-based applications, environmental- and sustainability-based applications, and biocatalytic and biotransformation applications are of supreme interest. Considering the above points, herein we reviewed current advances in multifunctional hNFs, with particular emphasis on (1) critical factors, (2) different metal/non-metal-based synthesizing processes (i.e., (i) copper-based hNFs, (ii) calcium-based hNFs, (iii) manganese-based hNFs, (iv) zinc-based hNFs, (v) cobalt-based hNFs, (vi) iron-based hNFs, (vii) multi-metal-based hNFs, and (viii) non-metal-based hNFs), and (3) their applications. Moreover, the interfacial mechanism involved in hNF development is also discussed considering the following three critical points: (1) the combination of metal ions and organic matter, (2) petal formation, and (3) the generation of hNFs. In summary, the literature given herein could be used to engineer hNFs for multipurpose applications in the biosensing, biocatalysis, and other environmental sectors.

scholarly journals Speciation of organosulfur compounds in carbonaceous chondrites

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexander Zherebker ◽  
Yury Kostyukevich ◽  
Dmitry S. Volkov ◽  
Ratibor G. Chumakov ◽  
Lukas Friederici ◽  
...  
Keyword(s):  
Organic Matter ◽  
Analytical Techniques ◽  
Ion Cyclotron Resonance ◽  
Organosulfur Compounds ◽  
Low Oxygen ◽  
Fticr Ms ◽  
Insoluble Organic Matter ◽  
Composition And Structure ◽  
Extractable Fraction ◽  
The Individual

AbstractDespite broad application of different analytical techniques for studies on organic matter of chondrite meteorites, information about composition and structure of individual compounds is still very limited due to extreme molecular diversity of extraterrestrial organic matter. Here we present the first application of isotopic exchange assisted Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) for analysis of alkali extractable fraction of insoluble organic matter (IOM) of the Murchison and Allende meteorites. This allowed us to determine the individual S-containing ions with different types of sulfur atoms in IOM. Thiols, thiophenes, sulfoxides, sulfonyls and sulfonates were identified in both samples but with different proportions, which contribution corroborated with the hydrothermal and thermal history of the meteorites. The results were supported by XPS and thermogravimetric analysis coupled to FTICR MS. The latter was applied for the first time for analysis of chondritic IOM. To emphasize the peculiar extraterrestrial origin of IOM we have compared it with coal kerogen, which is characterized by the comparable complexity of molecular composition but its aromatic nature and low oxygen content can be ascribed almost exclusively to degradation of biomacromolecules.

Effect of dissolved organic matter composition on metal speciation in soil solutions

2015 ◽  
Vol 398 ◽  
pp. 61-69 ◽  
Author(s):  
Zong-Ling Ren ◽  
Marie Tella ◽  
Matthieu N. Bravin ◽  
Rob N.J. Comans ◽  
Jun Dai ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Metal Speciation ◽  
Organic Matter Composition ◽  
Soil Solutions

CLAY ILLUVIATION IN SOME ORTHIC PODZOLS OF EASTERN CANADA

1965 ◽  
Vol 45 (2) ◽  
pp. 127-138 ◽  
Author(s):  
J. E. Brydon
Keyword(s):  
Organic Matter ◽  
New Brunswick ◽  
Iron Oxides ◽  
Clay Content ◽  
Granular Structure ◽  
Charge Component ◽  
Eastern Canada ◽  
Free Iron ◽  
Fine Clay ◽  
Ph Dependent

The Arago, Barney, and Holmesville soils, Podzols from Quebec, Nova Scotia, and New Brunswick, respectively, each had friable Bfh horizons with moderate granular structure, and with organic matter and free Fe2O3 contents greater than the Ae and C horizons. The Arago and Holmesville had thin Bhft horizons containing over 10% organic matter and 5% free iron oxides. The C horizons of these two soils had some features characteristic of fragipans.The B horizons of the three soils had a high "pH-dependent charge component" in the C.E.C. values. The "permanent charge component" was similar throughout the Arago profile except for the Bhft horizon where clay accumulation had occurred.Translocation of clay from the Ae to the upper B horizons was indicated by the twofold increase in clay content and the relative enrichment of fine clay in the B horizons. Removal of free iron affected the clay contents differently in the different: horizons but the maximum clay content in the upper B horizons remained. The definitions of Orthic Podzols, Textural Podzols, and t horizons should be re-examined.

Elemental content of mast cell granules measured by X-ray microanalysis of rat thymic tissue sections

1986 ◽  
Vol 83 (1) ◽  
pp. 77-87 ◽  
Author(s):  
M.D. Kendall ◽  
A. Warley
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Elemental Content ◽  
Thymic Tissue ◽  
X Ray ◽  
Tissue Sections ◽  
Freeze Dried ◽  
The Mean ◽  
Highly Correlated ◽  
The Individual

Mast cell granules were examined by fully quantitative X-ray microanalysis of 20 cells in freeze-dried cryosections. The mast cells were situated mainly in the connective tissue of the thymic capsule of five adult male Carworth Sprague Europe rats. In addition 30 red blood cells were analysed from the same sections. Nineteen of the mast cells had granules rich in S and K. One cell had smaller granules, and in this cell the granules contained high [Ca] and [P] instead of high [S] and [K]. In the majority of cells (13) the S:K ratio was highly correlated and less than 2.2, whereas in the remaining six cells the individual granule ratios were very variable in any one cell and much higher. The mean granule [K] (994 +/− 57 mmol kg-1 dry wt) was about four times the mean cytoplasmic level of 227 +/− 81 mmol kg-1 dry wt. The existence of this difference in concentration between the granules and the cytoplasm suggests that the K in the granules must be bound. The relationship between the [K] and [S] is discussed with regard to the possible binding of heparin and amines in the granules.

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