Extensions of CASH+ thermodynamic solid solution model for the uptake of alkali metals and alkaline earth metals in C-S-H

AbstractThe possibility to use alkali metals and alkaline earth metals as slightly sorbing tracers in in-situ sorption experiments in high saline groundwaters has been investigated. The cation exchange characteristics of granite and some fracture minerals (chlorite and calcite) have been studied using the proposed cations as tracers. The results show low Kd’s for Na, Ca and Sr (∽0.1 ml/g), while the sorption is higher for the more electropositive cations (Rb, Cs and Ba). A higher contribution of irreversible sorption can also be observed for the latter group of cations. For calcite the sorption of all the tracers, except Ca, is lower compared to the corresponding sorption to granite and chlorite. Differences in selectivity coefficients and cation exchange capacity are obtained when using different size fractions of crushed granite. The difference is even more pronounced when comparing crushed granite to intact granite.

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Superconducting films of alkali metals and their alloys with alkaline earth metals

Physics Letters A ◽

10.1016/0375-9601(75)90695-7 ◽

1975 ◽

Vol 55 (3) ◽

pp. 165-166 ◽

Cited By ~ 8

Author(s):

C. Reale

Keyword(s):

Alkali Metals ◽

Alkaline Earth ◽

Superconducting Films ◽

Alkaline Earth Metals

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Crossover from metal to insulator in dense lithium-rich compound CLi4

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1525412113 ◽

2016 ◽

Vol 113 (9) ◽

pp. 2366-2369 ◽

Cited By ~ 10

Author(s):

Xilian Jin ◽

Xiao-Jia Chen ◽

Tian Cui ◽

Ho-kwang Mao ◽

Huadi Zhang ◽

...

Keyword(s):

Phase Transition ◽

Density Functional Theory ◽

Fermi Surface ◽

Density Functional ◽

Alkali Metals ◽

Alkaline Earth ◽

Density Functional Theory Calculations ◽

Alkaline Earth Metals ◽

Functional Theory ◽

Surface Filling

At room environment, all materials can be classified as insulators or metals or in-between semiconductors, by judging whether they are capable of conducting the flow of electrons. One can expect an insulator to convert into a metal and to remain in this state upon further compression, i.e., pressure-induced metallization. Some exceptions were reported recently in elementary metals such as all of the alkali metals and heavy alkaline earth metals (Ca, Sr, and Ba). Here we show that a compound of CLi4 becomes progressively less conductive and eventually insulating upon compression based on ab initio density-functional theory calculations. An unusual path with pressure is found for the phase transition from metal to semimetal, to semiconductor, and eventually to insulator. The Fermi surface filling parameter is used to describe such an antimetallization process.

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Synthesis of a Novel Macroporous Silica-Calix[4]arene-Crown Polymeric Composite and Its Adsorption for Alkali Metals and Alkaline-Earth Metals

Industrial & Engineering Chemistry Research ◽

10.1021/ie901622y ◽

2010 ◽

Vol 49 (5) ◽

pp. 2047-2054 ◽

Cited By ~ 15

Author(s):

Anyun Zhang ◽

Qihui Hu ◽

Zhifang Chai

Keyword(s):

Alkali Metals ◽

Alkaline Earth ◽

Polymeric Composite ◽

Alkaline Earth Metals ◽

Macroporous Silica

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Cation-Exchange Equilibria in a Carboxylic Cation Exchanger and in Attapulgite Clay

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v44i4.13810 ◽

1969 ◽

Vol 44 (4) ◽

pp. 221-235

Author(s):

Gilberto García Monge

Keyword(s):

Alkali Metals ◽

Alkaline Earth ◽

Cation Exchanger ◽

Alkaline Earth Metals ◽

Strong Electrolyte ◽

Weak Electrolyte ◽

Resin Phase ◽

Carboxylic Groups ◽

Marked Selectivity ◽

Attapulgite Clay

Selectivity numbers for a synthetic cation exchanger of the carboxylic type (IRC-50) and the natural cation exchanger, attapulgite clay mineral, were determined for different pairs of cations. The results in IRC-50 for Na+-K+, Na+-Rb+, and Na+-Cs+ systems showed no marked selectivity. The resin phase was considered to act as a concentrated salt solution. Hence, differences in the selectivity numbers (K) were attributed to the differences in the activity coefficients in the concentrated resin-phase solution. In the alkaline-earth systems (Mg++-Ca++, Mg++-Sr++, and Mg++-Ba++) the resin showed more selectivity between its members than between those of the alkali series. The selectivity numbers were functions of the percentage of Mg in the resin. In the Mg++-Ca++ system, Mg++ appeared more strongly held at low percentages of Mg, whereas in the Mg++-Ba++ system, Ba++ appeared more strongly held at all percentages of Mg in the resin. These results were explained on the basis of formation of slightly dissociated complexes of the alkaline-earth metals with the carboxylic groups of the exchanger. The results in attapulgite clay for the Na+-K+, Na+-Rb+, and Na+-Cs+ systems showed marked selectivity. The selectivity numbers were functions of the percentage of Na in the clay. The differences in selectivity were greater in the Na+-Cs+ system than in the Na+-Rb+ system and, in the Na+-Rb+ system, greater than in the Na+-K+ system. The results were broadly understood on the basis of the bifunctional character of the clay. The differences in the selectivity numbers for the alkaline-earth metals in the clay (Mg, Ca, Sr, and Ba) are small as compared with those of the alkali metals. In general, the resin behaved as a moderately strong electrolyte with respect to the alkali metals. It behaved like a weak electrolyte with respect to the alkaline-earth metals. Attapulgite clay behaved like a weak electrolyte with respect to both the alkali metals and alkaline-earth metals. The results of the selectivitynumber curves for the clay resembled those of a bifunctional cation exchanger and a high cross-linkage resin.

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