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

The properties of cellulose chelating ion exchangers Ostsorb have been studied in the sorption of cadmium and lead from aqueous solutions. The Cd(II) and Pb(II) ions are trapped by the Ostsorb OXIN and Ostsorb DETA ion exchangers most effectively in neutral and alkaline media but at these conditions formation of stable hydrolytic products of both metals competes with the exchange equilibria. From this point of view, Ostsorb DTTA appears to be a more suitable sorbent since it traps the Pb(II) and Cd(II) ions in acidic media already. Chloride ions interfere with the sorption of the two metals by Ostsorb DTTA whereas the ionic strength adjusted by the addition of sodium perchlorate does not affect the exchange capacity of this ion exchanger.

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Effects of pH and ionic strength on the cation exchange capacity of soils with variable charge

Soil Research ◽

10.1071/sr9810093 ◽

1981 ◽

Vol 19 (1) ◽

pp. 93 ◽

Cited By ~ 30

Author(s):

GP Gillman

Keyword(s):

Ionic Strength ◽

Cation Exchange ◽

Cation Exchange Capacity ◽

Exchange Capacity ◽

Surface Soils ◽

Ph Values ◽

Variable Charge ◽

Effects Of Ph ◽

Variable Charge Soils

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 ionic strength on the aggregation kinetics of the amidated amyloid beta peptide Aβ (1-40) in aqueous solutions

Biophysical Chemistry ◽

10.1016/j.bpc.2017.05.004 ◽

2017 ◽

Vol 228 ◽

pp. 98-107 ◽

Cited By ~ 2

Author(s):

Adriana Campos-Ramírez ◽

Maripaz Márquez ◽

Liliana Quintanar ◽

Luis F. Rojas-Ochoa

Keyword(s):

Ionic Strength ◽

Aqueous Solutions ◽

Amyloid Beta ◽

Amyloid Beta Peptide ◽

Aggregation Kinetics ◽

Beta Peptide ◽

Kinetics Of

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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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Highly efficient carbonaceous nanofiber/layered double hydroxide nanocomposites for removal of U(VI) from aqueous solutions

Radiochimica Acta ◽

10.1515/ract-2018-3061 ◽

2019 ◽

Vol 107 (4) ◽

pp. 299-309

Author(s):

Shuqi Yu ◽

Xiangxue Wang ◽

Shunyan Ning ◽

Zhongshan Chen ◽

Xiangke Wang

Keyword(s):

Ionic Strength ◽

Aqueous Solutions ◽

Layered Double Hydroxide ◽

Photoelectron Spectroscopy ◽

Environmental Remediation ◽

Three Dimensional ◽

Order Kinetic ◽

Surface Bonding ◽

Double Hydroxide ◽

Shed Light

Abstract The three-dimensional (3D) carbonaceous nanofiber and Ni-Al layered double hydroxide (CNF/LDH) nanocomposite was successfully prepared by a facile one-step hydrothermal methodology. Characterization of scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), XRD, and Fourier transformed infrared spectroscopy (FTIR) provided a demonstration that the modified CNF/LDH nanocomposite possessed abundant functional groups, for instance, metal-oxygen surface bonding sites (Ni–O as well as Al–O) and free-metal surface bonding sites (C–O, C–O–C, as well as O–C=O). The elimination of representative radionuclide (i.e. U(VI)) on the CNF/LDH nanocomposite from aqueous solutions was explored as a key function of pH, ionic strength, contact time, reaction temperature as well as radionuclide preliminary concentrations with the use of the batch methodology. As revealed by the findings, the sorption of radionuclides on CNF/LDH nanocomposite adhered to the pseudo-second-order kinetic model as well as Langmuir model. The maximum elimination capacity of U(VI) amounted to be 0.7 mmol/g. The independent of ionic strength shed light on the fact that inner-sphere surface complexation mainly overpowered radionuclide uptake by the CNF/LDH nanocomposite, which was further verified through the combination of FTIR and XPS spectral analyses. The abovementioned analyses shed light on the fact that the CNF/LDH nanocomposite can be regarded as a latent material to preconcentration radionuclides for environmental remediation.

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Calorimetric Study on the Self Association of Promethazine Hydrochloride in Aqueous Solutions of High Ionic Strength

Surfactants in Solution ◽

10.1007/978-1-4615-7984-7_16 ◽

1989 ◽

pp. 265-276 ◽

Cited By ~ 1

Author(s):

D. Attwood ◽

P. Fletcher ◽

E. Boitard ◽

J. P. Dubes ◽

H. Tachoire

Keyword(s):

Ionic Strength ◽

Aqueous Solutions ◽

High Ionic Strength ◽

The Self ◽

Calorimetric Study ◽

Promethazine Hydrochloride ◽

Self Association

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The dependence of electrophoretic and spectroscopic properties of the pyruvate dehydrogenase complex on mono- and divalent ions.

Acta Biochimica Polonica ◽

10.18388/abp.1994_4775 ◽

1994 ◽

Vol 41 (1) ◽

pp. 63-72

Author(s):

T Pawełczyk ◽

R A Easom ◽

M S Olson

Keyword(s):

Ionic Strength ◽

Pyruvate Dehydrogenase ◽

Pyruvate Dehydrogenase Complex ◽

Fluorescence Emission ◽

Emission Spectra ◽

Spectroscopic Properties ◽

Uv Absorption ◽

Divalent Ions ◽

Fluorescence Emission Spectra ◽

Dehydrogenase Complex

The effects of various mono- and divalent ions on the pyruvate dehydrogenase complex (PDC) were investigated. To determine the radius of PDC under various conditions a two-dimensional agarose gel electrophoresis technique was used. The radius of PDC cross-linked with glutaraldehyde at ionic strength 0.04 M was calculated to be 22.0 +/- 0.1 nm. The presence of K+, Na+ or HPO4(2-) prevented changes in electromobility and of the calculated radius of PDC induced by alteration in ionic strength. The fluorescence emission spectra of PDC depended on the ionic strength and monovalent cations. The fluorescence intensity of PDC increased in the presence of 80 mM K+, and decreased in the presence of 80 mM Na+ with no shift in the emission maximum wavelength. Changes in the ionic strength to which PDC was exposed resulted in alteration of the UV absorption spectra in the 230 nm region. These alterations were prevented by HPO4(2-), whereas Na+ or K+ ions had no effect on the UV absorption spectrum of PDC.

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Kinetic and Equilibrium Studies on the Zinc Adsorption-desorption Characteristics of Some Promising Biochars in Aqueous Solutions

10.21203/rs.3.rs-252281/v1 ◽

2021 ◽

Author(s):

Masoumeh Faryadi Shahgoli ◽

Adel Reyhanitabar ◽

Nosratollah Najafi ◽

Shahin Oustan

Keyword(s):

Ionic Strength ◽

Aqueous Solutions ◽

Rice Straw ◽

Pyrolysis Temperature ◽

Ph Effect ◽

Solution Ph ◽

Equilibrium Studies ◽

Batch Technique ◽

Adsorption Desorption ◽

Zinc Adsorption

Abstract The present research aimed at investigating zinc (Zn) sorption capacity of the biochars derived from apple wood (WB) and rice straw (RB) feedstocks at two 300 and 600°C pyrolysis temperatures (WB300, WB600, RB300 and RB600, respectively) in aqueous solutions. Kinetic and equilibrium sorption experiments were conducted via batch technique. In equilibrium adsorption experiments, the study used the concentration range of 5-200 mg Zn L− 1 and focused on the solution pH effect on Zn adsorption in biochars under the following conditions: unadjusted and adjusted pH (4 and 6) and three ionic strength levels (0.01, 0.03, 0.1 M KNO3). Zinc desorption experiments were conducted under all above mentioned conditions but without pH adjustment at five separate stages. Kinetic data analysis indicated that Zn adsorption in biochars reached the near steady state within 24 hours with the sorption rate order of WB300 < WB600 < RB300 < RB600. The best fitness was superior to both Elovich and exponential rate models. Also, Zn adsorption isotherms in the studied biochars were shown to fit quite well to Langmuir, Freundlich and Dubinin-Radushkevich models. Zn sorption maxima were found to be 4.3, 16.4, 17.9 and 33.3 mg g− 1, on average, for WB300, WB600, RB300, and RB600, respectively. The initial increased pH solution from 4 to 6 caused an increase in Zn adsorption in RB600, RB300 and WB600, however the sorption maxima in WB300 was detected at pH 4. The rise in solution ionic strength from 0.01 M to 0.1 M dropped the Zn adsorption capacity in all the studied biochars. Findings suggested that rice straw derived biochars showed a better performance than woody biochars in Zn sorption and retention from aqueous solutions. In addition, this ability increased with increasing pyrolysis temperature in both types of biochars. Finally, the study revealed that rice straw biochars, produced at high pyrolysis temperatures, can serve as economical and efficient absorbents for Zn removal from aqueous solutions.

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