Some thermodynamic properties of dl-Tyrosine and dl-Tryptophan. Effect of the ionic medium, ionic strength and temperature on the solubility and acid–base properties

2012 ◽  
Vol 314 ◽  
pp. 185-197 ◽  
Author(s):  
Clemente Bretti ◽  
Francesco Crea ◽  
Concetta De Stefano ◽  
Silvio Sammartano ◽  
Giuseppina Vianelli
Keyword(s):  
Ionic Strength ◽  
Thermodynamic Properties ◽  
Acid Base ◽  
Ionic Medium ◽  
Base Properties

Synthesis, Acid-Base Properties, Kinetics and Mechanism of Cu2+ Incorporation into Water-Soluble Highly Substituted Porphyrins

2017 ◽  
Vol 21 (09) ◽  
pp. 611-621
Author(s):  
Hirofumi Konno ◽  
Jun Takeda
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Kinetics And Mechanism ◽  
Water Soluble ◽  
Acid Base ◽  
Base Equilibrium ◽  
Absorbance Change ◽  
Acid Base Equilibrium ◽  
Kinetics Of ◽  
Base Properties

The synthesis, acid-base properties, and kinetics of Cu[Formula: see text] incorporation into water-soluble highly substituted porphyrins were studied. The basicity increased and the stepwise acid-base equilibrium was clarified by increasing the number of phenyl groups at the [Formula: see text] position, and the basicity of a dodeca-substituted porphyrin increased with the ionic strength. The metalation reaction of the dodeca-substituted porphyrin with Cu[Formula: see text] in aqueous solution revealed a biphasic absorbance change at 453 nm. Plots of [Formula: see text] or[Formula: see text] vs. the Cu[Formula: see text] concentration and of log ([Formula: see text] or[Formula: see text]/[Formula: see text] 0) vs. the ionic strength show that [Formula: see text] is dependent on the Cu[Formula: see text] concentration and ionic strength, while [Formula: see text] is independent of these parameters. These results confirm the stepwise metalation mechanism and the existence of an intermediate in aqueous solution, which is indicated by the biphasic absorbance change at 453 nm.

scholarly journals Acid-base properties of kaolinite, montmorillonite and illite at marine ionic strength

2018 ◽  
Vol 483 ◽  
pp. 191-200 ◽  
Author(s):  
Yuxia Liu ◽  
Daniel S. Alessi ◽  
Shannon L. Flynn ◽  
Md. Samrat Alam ◽  
Weiduo Hao ◽  
...  
Keyword(s):  
Ionic Strength ◽  
Acid Base ◽  
Base Properties

On the interaction of phytate with proton and monocharged inorganic cations in different ionic media, and modeling of acid-base properties at low ionic strength

2015 ◽  
Vol 90 ◽  
pp. 51-58 ◽  
Author(s):  
Clemente Bretti ◽  
Rosalia Maria Cigala ◽  
Concetta De Stefano ◽  
Gabriele Lando ◽  
Demetrio Milea ◽  
...  
Keyword(s):  
Ionic Strength ◽  
Acid Base ◽  
Inorganic Cations ◽  
Ionic Media ◽  
Low Ionic Strength ◽  
Base Properties

Electrochemical Study of Acid-Base Properties of Some 2,5-Dihydro-1,3,4-thiadiazoles in Aqueous-Ethanolic Solutions

1998 ◽  
Vol 63 (1) ◽  
pp. 31-41
Author(s):  
Maria Turowska ◽  
Grzegorz Mloston ◽  
Pawel Krzyczmonik ◽  
Jacek Raczak ◽  
Jaroslaw Romanski
Keyword(s):  
Ionic Strength ◽  
Dissociation Constants ◽  
Mndo Method ◽  
Electrochemical Study ◽  
Acidic Properties ◽  
Acid Base ◽  
Weak Bases ◽  
Formation Enthalpies ◽  
Protonated Forms ◽  
Base Properties

The dissociation constants Ka for spherically crowded 2'- and 2,5-substituted thiadiazolines and their protonated forms in 45% (v/v) aqueous-ethanolic solutions (ionic strength m = 0.1) were determined using the pH-metric method. All the thiadiazoles are weak bases. Some of them showed also weak acidic properties. The formation enthalpies have been calculated using the MNDO method. On the basis of the obtained results the mechanism of the protonation process is discussed.

Sign in / Sign up

Export Citation Format

Share Document