Of aqueous cations

Fig. 2.37. Phase diagram for Ca0-Na20 Si02-(Al203)-H20 system in equilibrium with quartz at 400°C and 400 bars. Plagioclase solid solution can be represented by the albite and anorthite fields, whereas epidote is represented by clinozoisite. Note that the clinozoisite field is adjacent to the anorthite field, suggesting that fluids with high Ca/(H+) might equilibrate with excess anorthite by replacing it with epidote. The location of the albite-anorthite-epidote equilibrium point is a function of epidote and plagioclase composition and depends on the model used for calculation of the thermodynamic properties of aqueous cations (Berndt et al., 1989).

Shock EL, Sassani DC, Willis M, Sverjensky DA (1997) Inorganic species in geologic fluids Correlations among standard molal thermodynamic properties of aqueous cations and hydroxide complexes. Geochim... 

Fig.1 Formation of aqueous cation from element in its standard state.

The purpose of this chapter is to present a brief overview of the geochemistry of mineral surfaces, including their (1) dissolution mechanisms, (2) development of electrical charge when in contact with aqueous solutions, and (3) uptake of aqueous cations and anions, and to discuss some of the factors that control their chemical reactivity, including (1) defect density, (2) cooperative effects among adsorbates,... 

The example discussed above shows the effect of different solid substrates on the adsorption of a single type of aqueous cation [Co(II)]. The uptake vs. pH curves in Figure 7.6 show the differences in uptake behavior as a function of pH for a variety of aqueous cations and anions on one type of substrate - ferric hydroxide particles [5]. Some of the cations included in Figure 7.6(a), like Pb2+ and Cr3+, sorb at low pH values, whereas others, like Zn2+ and Ni2+, do not sorb until higher pH values are reached. At low pH values, metal oxide and hydroxide surfaces tend to... 

We will now proceed to a discussion of LIS methodologies, uses of lanthanides in complex NMR spectra, quantitative aspects of the LIS method such as testing and separation of shifts, use of pseudo contact shift in molecular structure, and use of aqueous cations and lanthanide complexes in biological systems. 

Such systems can form the thread-like micelles necessary for surfactant solutions to be DR under the shearing conditions in turbulent flows. The thread-like micelles align themselves along the flow direction causing DR of the solution. Details of microstructures DR of aqueous cationic surfactant solutions vary with surfactant chemical structure and concentration, counterion chemical structure and... 

LI2 Liu, R., Cellesi, F., Tirelli, N., Saunders, B.R., A study of thermoassociative gelation of aqueous cationic poly(7V-isopropylaciylamide) graft copolymer solutions. Polymer, 50, 1456, 2009. 

X-ray absorption fine structure spectroscopy has become one of the key molecular-scale methods in studies of reactions mechanisms of aqueous cations and anions at environmental interfaces. 

Parac TN, Caulder DL, Raymond KN (1998) Selective encapsulation of aqueous cationic guests into a supramolecular tetrahedral [M4LJ anionic host. J Am Chem Soc 120(31) 8003-8004... 

For minerals crystaUizing from low-temperature aqueous solutions, the primary controls on their stability should be (a) the activity of the species in solution and G ) protonation reactions between solid and solution at the edges of polyhedron chains deprotonation of edge anions promotes attachment of aqueous cation species (i.e., crystallization), whereas protonation of edge anions weakens their bonds to the bulk structure and promotes dissolution. With regard to crystallization, the character and activity of the aqueous species is of interest as these provide groups of atoms that may attach to the solid during crystallization. 

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