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Potassium isotopic composition of the Moon
Geochimica et Cosmochimica Acta, 2020Abstract The Moon is depleted in water and other volatiles compared to Earth and the bulk solar composition. Such depletion of volatile elements and the stable isotope fractionations of these elements can be used to better understand the origin and early differentiation history of the Moon.
Zhen Tian +7 more
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Enrichment of Potassium Isotopes with Macrocyclic Polyether Potassium Complexes
Helvetica Chimica Acta, 1982AbstractEnrichment of the potassium isotopes is achieved by means of the chemical exchange reaction Where L represents a macrocyclic polyether. Dicyclohexyl‐18‐crown‐6 ((cis‐syn‐cis)‐isomer) was investigated. The single stage‐separation factor a=1+ε was determined according to the method of Glueckauf from the elution curve and iso‐topic assays.
Beat Schmidhaltcr, Ernst Schumacher
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Isotopic Composition of Potassium
Nature, 1960RECENT measurements1–6 of the natural isotopic composition of potassium have yielded values for the potassium-39/potassium-41 ratio ranging from 13.48 ± 0.07 (Nier) to 13.96 ± 0.05 (Omura and Morito). These results are not inconsistent with the presence of variations of 1 or 2 per cent in the potassium-39/potassium-41 ratio for different samples ...
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Experiments With Potassium Isotopes
2005Experiments on cooling and trapping of potassium are strongly motivated by the occurrence of three isotopes: K, K, K with a relative abundance of 93.26%, 0.012% and 6.73%, respectively. K and K are bosons while K is a fermion, therefore potassium is a good candidate to study a degenerate dilute Fermi gas and bosons-fermions mixtures.
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Isotope Effect in Potassium Dihydrogen Phosphate
Nature, 1939WHEN the hydrogen in potassium dihydrogen phosphate (KH2PO4) is replaced by deuterium by repeated crystallization from warm 99·6 per cent heavy water (D2O), the potassium phosphate separates in a different crystal structure. It can with some difficulty also be made to crystallize in the tetragonal form described by West1, by adding a nucleus of KH2PO4 ...
A. R. UBBELOHDE, I. WOODWARD
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Potassium isotope systematics of oceanic basalts
Geochimica et Cosmochimica Acta, 2019Abstract High-temperature isotope fractionation during partial melting and other igneous differentiation processes has been observed in many non-traditional isotope systems. The potassium (K) isotope system has not been extensively investigated historically due to the lack of high-precision analysis methods; however, the recent development of the ...
Brenna Tuller-Ross +5 more
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The isotopes of lithium, sodium, and potassium
Journal of the Franklin Institute, 1931Abstract Part I. The relative abundance of the isotopes of lithium. Magnetic analysis of the positive rays of lithium from a heated spodumene source shows no change with temperature in the relative abundance of Li7 and Li6. This is in agreement with Aston and Morand but at variance with the results of G. P.
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Potassium isotopic composition of Australasian tektites
Meteoritics & Planetary Science, 2004Abstract— We have analyzed the potassium isotopic composition of four tektites from the Australasian strewn field, spanning a wide diversity of thermal histories, inferred from textures and volatile element contents. Our results indicate no isotopic differences between tektites and terrestrial crustal rocks, placing stringent limits of ≤2% loss of ...
Humayun, Munir, Köberl, Christian
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ChemInform Abstract: ENRICHMENT OF POTASSIUM ISOTOPES WITH MACROCYCLIC POLYETHER POTASSIUM COMPLEXES
Chemischer Informationsdienst, 1983AbstractEine Anreicherung von K‐Isotopen wird mit Hilfe der chemischen Austauschreaktion A erreicht.
B. SCHMIDHALTER, E. SCHUMACHER
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Chemistry, Radiochemistry and Applications of Potassium Isotopes
1995Potassium (K) is a principal cation in the intracellular fluid and an important constituent of the extracellular fluid. It influences a number of physiological processes; specifically muscle activity (ie. cardiac muscle) by affecting the cellular resting potential and the cell excitability (1,2).
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