Effects of pH and Ionic Strength on Zinc Sorption by a Variable Charge Soil

The cation exchange capacity of six surface soils from north Queensland and Hawaii has been measured over a range of pH values (4-6) and ionic strength values (0.003-0.05). The results show that for variable charge soils, modest changes in electrolyte ionic strength are as important in their effect on caton exchange capacity as are changes in pH values.

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Effect of pH, Ionic Strength and Heavy Metal Ions on p-Nitrophenol Adsorption by Variable Charge Soil of South China

Asian Journal of Chemistry ◽

10.14233/ajchem.2014.15788 ◽

2014 ◽

Vol 26 (9) ◽

pp. 2655-2660 ◽

Cited By ~ 2

Author(s):

J.Y. Zhang ◽

C.D. Wu ◽

Z.L. Zhang

Keyword(s):

Heavy Metal ◽

Ionic Strength ◽

Metal Ions ◽

South China ◽

Heavy Metal Ions ◽

Effect Of Ph ◽

Variable Charge ◽

Variable Charge Soil

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Phosphate adsorption at variable charge soil/water interfaces as influenced by ionic strength

Soil Research ◽

10.1071/sr08181 ◽

2009 ◽

Vol 47 (5) ◽

pp. 529 ◽

Cited By ~ 8

Author(s):

Yong Wang ◽

Jun Jiang ◽

Ren-kou Xu ◽

Diwakar Tiwari

Keyword(s):

Ionic Strength ◽

Zeta Potential ◽

Salt Effect ◽

Phosphate Adsorption ◽

Adsorption Model ◽

Net Charge ◽

Variable Charge ◽

Opposite Trend ◽

Variable Charge Soil ◽

Soil Colloids

The effect of phosphate adsorption on zeta potential of the colloids of variable charge soils and the effect of ionic strength on phosphate adsorption by the soils were investigated using batch experimental method. The presence of phosphate resulted in the decrease in zeta potential and isoelectric point (IEP) of the colloids of the soils, which further suggested that the phosphate was adsorbed specifically by these soils. The effect of phosphate adsorption on zeta potential was correlated with the content of free Fe/Al oxides in the soils; the higher the content of Fe/Al oxides in a soil the greater was the decrease in zeta potential and IEP of the soil colloids. The intersection of phosphate adsorption–pH curves at different ionic strengths (a characteristic pH) was obtained for 2 Oxisols. Above this pH, the adsorption of phosphate increased with increasing ionic strength, whereas below it the reverse trend occurred. The intersect pH was 4.60 for the Oxisol from Guangdong and 4.55 for the Oxisol from Yunnan, which was lower than the values of PZSE (point of zero salt effect) of these soils, but near the PZNC (point of zero net charge) of the soils. The effects of ionic strength and pH on phosphate adsorption by these soils were interpreted with the help of an adsorption model developed previously by Bowden et al. The results of zeta potential suggested that the potential in an adsorption plane became less negative with increasing ionic strength above the soil PZNC and decreased with increasing ionic strength below the soil PZNC. These results support the hypothesis of the adsorption model that the potential in the adsorption plane changed with ionic strength with an opposite trend to the surface charge of these soils. The phosphate adsorption by these soils was related not only to the ionic strength but also to the types of electrolytes present. K+ induced a greater increase in phosphate adsorption than Na+ due to the greater affinity of the soils to K+ than Na+.

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Effects of pH and ionic strength on the structure and spectroscopic properties of Fe(III) complex porphyrin in aqueous solutions

Conference Digest. 2000 Conference on Lasers and Electro-Optics Europe (Cat. No.00TH8505) ◽

10.1109/cleoe.2000.910029 ◽

2000 ◽

Author(s):

A.S.L. Gomes ◽

M. Trsic ◽

I.E. Borissevitch ◽

E.A. Vidoto ◽

O.R. Nascimento ◽

...

Keyword(s):

Ionic Strength ◽

Aqueous Solutions ◽

Spectroscopic Properties ◽

Effects Of Ph

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Evaluation of effects of pH and ionic strength on colloidal stability of IgG solutions by PEG-induced liquid-liquid phase separation

The Journal of Chemical Physics ◽

10.1063/1.4966708 ◽

2016 ◽

Vol 145 (18) ◽

pp. 185101 ◽

Cited By ~ 14

Author(s):

Ronald W. Thompson ◽

Ramil F. Latypov ◽

Ying Wang ◽

Aleksey Lomakin ◽

Julie A. Meyer ◽

...

Keyword(s):

Phase Separation ◽

Ionic Strength ◽

Liquid Phase ◽

Colloidal Stability ◽

Liquid Phase Separation ◽

Effects Of Ph ◽

Liquid Liquid Phase Separation

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Effects of pH, aluminium, and soft water on larvae of the amphibians Bufo bufo and Triturus vulgaris

Canadian Journal of Zoology ◽

10.1139/z06-166 ◽

2006 ◽

Vol 84 (11) ◽

pp. 1668-1677 ◽

Cited By ~ 4

Author(s):

Jon K. Skei ◽

Dag Dolmen

Keyword(s):

Ionic Strength ◽

High Mortality ◽

Bufo Bufo ◽

Soft Water ◽

Internal Environment ◽

Triturus Vulgaris ◽

Effects Of Ph ◽

Low Ionic Strength

Larval Bufo bufo (L., 1758) and Triturus vulgaris (L., 1758) were exposed to soft water (0.5 mg·L–1 Ca2+) experimentally acidified to pH 3.9 to 5.9 and total aluminium concentrations of <10, 150, and 300 µg·L–1. Below pH 4.5 both species experienced increased mortality. The LC50 (168 h) for <10 and 150 µg·L–1 Al was pH 4.3 and 4.1 for B. bufo and 4.2 and 4.1 for T. vulgaris. However, Al3+ increased the survival of both species, which may be due to the contribution of Al3+ to the ionic strength. No B. bufo larvae died at pH >4.5, whereas T. vulgaris at higher Al concentrations suffered relatively high mortality at pH 5.1–5.9, where Al occurs mainly as Al(OH)2+ and Al(OH)2+. Unlike external gills (T. vulgaris), internal gills (B. bufo) have their own internal environment and are probably better protected against the presence of these toxic Al species in the water. These Al species thus seem to be toxic to T. vulgaris larvae but not to B. bufo. Chloride was seen to be important for survival in water of low ionic strength, since the survival of T. vulgaris larvae, particularly at low Al concentration, increased at pH levels down to pH 4.3 when the water was acidified with HCl.

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