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Alkali Blues: Blue‐Emissive Alkali Metal Pyrrolates
Chemistry – A European Journal, 2019Abstract2‐Iminopyrroles [HtBuL, 4‐tert‐butyl phenyl(pyrrol‐2‐ylmethylene)amine] are non‐fluorescent π systems. However, they display blue fluorescence after deprotonation with alkali metal bases in the solid state and in solution at room temperature. In the solid state, the alkali metal 2‐imino pyrrolates, M(tBuL), aggregate to dimers, [M(tBuL)(NCR)]2 (
Oliver Back +3 more
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Superatoms and their assemblies based on alkali and super-alkali motifs
Journal of Computational Methods in Sciences and Engineering, 2008It is shown that chosen stable clusters can mimic the chemical behavior of atoms in the periodic table and hence can be regarded as superatoms forming a third dimension of the periodic table. The review discusses the developments leading to the superatom concept and our recent studies on superhalogens and superalkalis.
Peneé A. Clayborne +5 more
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Thermodiffusion of alkali ions in alkali niobophosphate glasses
International Journal of Applied Glass Science, 2020Abstract A method is proposed for determination of the thermal diffusion coefficients of mobile ions through the study of ionic thermoelectric power. Ionic Seebeck coefficients and the heats of ion transport have been measured in [Li(Na,K)] 2 O‐Nb 2
Viktor A. Markov +2 more
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Effect of the inherent alkalis of alkali activated slag on the risk of alkali silica reaction
Cement and Concrete Research, 2017Abstract Alkali silica reaction (ASR) occurred in the alkali activated slag (AAS) concrete was evaluated by a revised mortar prism method. The mortars were made of blast furnace slags activated by alkali silicate solution possessing different modulus (0.5, 0.75, 1 and 2) as well as cations (sodium and potassium) and standard sand with a volume ...
Ricarda Tänzer, Yu Jin, Dietmar Stephan
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Core Exciton of Alkali and Alkali-Earth Halides
Journal of the Physical Society of Japan, 1993Low energy electron loss spectra (LEELS) of alkali halides LiF, NaCl, KCl, KBr, KI, RbBr and CsCl, and alkali-earth halides CaF 2 and CaCl 2 are measured for primary energies 30 to 900 eV. For K and Ca-halides, there are four loss peaks in the core exciton regions, some of which have not been observed in optical measurements and high energy electron ...
Teruhiko Mabuchi +2 more
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The vitrification of alkali borate and alkali silicate melts
Russian Journal of Physical Chemistry, 2006Glasses and crystals of compositions corresponding to the congruently melting compounds M2O·2SiO2 (M = Na. Rb, and Cs) and M2O·4SiO2 (M = K, Rb, and Cs) were studied by differential scanning calorimetry. The structure temperatures (T f) and excess entropies at T f of glasses were measured depending on the rate of cooling
V. M. Ushakov, N. V. Borisova
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The Cumulation of Alkali Earths and Alkali Metals on Alga
International Journal of Environmental Analytical Chemistry, 1983Abstract The cumulation of strontium, cesium, rubidium and sodium on alga has been radiometrically investigated at different pH and at different concentrations of elements studied in the absence and in the presence of other salts. It has been found that the cumulation can be quantitatively described using the affinity constants K M.
J. Starý, K. Kratzer, J. Prášilova
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2004
Abstract For multi-electron atoms we cannot solve the Hamiltonian analytically, but by making appropriate approximations we can explain their structure in a physically meaningful way. To do this, we start by considering the elementary ideas of atomic structure underlying the periodic table of the elements.
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Abstract For multi-electron atoms we cannot solve the Hamiltonian analytically, but by making appropriate approximations we can explain their structure in a physically meaningful way. To do this, we start by considering the elementary ideas of atomic structure underlying the periodic table of the elements.
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Heat of mixing of equiatomic alkali-alkali alloys
Journal of Physics F: Metal Physics, 1980The Gibbs-Bogoliubov variational technique is used to study the internal energy and entropy of liquid alkali metals as well as heat of mixing and excess entropy of mixing for equiatomic NaK, KRb and NaCs alloys. A Heine-Abarenkov-type model potential has been considered with Hartree, Hubbard-Sham and Vashishta-Singwi exchange and correlation functions.
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Alkali ionic transport in mixed alkali glasses
Journal of Non-Crystalline Solids, 1993Abstract The diffusion coefficient of an alkali ion in oxide glass, as well as dc conductivity, decreases drastically when a second alkali ion is introduced. This reduction in ionic transport rate is attributed to an increase in the activation energy. An expression is derived for the composition dependence of the activation energy for ionic transport
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