Results 211 to 220 of about 120,968 (266)

The isotope effect in ASDEX

Nuclear Fusion, 1993
The paper describes the effect of the isotopic mass on plasma parameters as observed in the ASDEX tokamak. The paper comprises Ohmic as well as L mode, H mode and H* mode scenarios. The measurements reveal that the ion mass is a substantial and robust parameter, which affects all the confinement times (energy, particle and momentum) in the whole ...
Bessenrodt-Weberpals, M., Wagner, F., Gehre, O., Giannone, L., Hofmann, J., Kallenbach, A., McCormick, K., Mertens, V., Murmann, H., Ryter, F., Scott, B., Siller, G., Söldner, F., Stäbler, A., Steuer, K., Stroth, U., Tsois, N., Verbeek, H., Zohm, H.   +18 more
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Electrochemical Isotope Effect and Lithium Isotope Separation

Journal of the American Chemical Society, 2009
A large electrochemical isotopic effect is observed upon the electrodeposition of lithium from solutions of propylene carbonate producing isotopically light metal deposits. The magnitude of fractionation is controlled by the applied overpotential and is largest close to equilibrium.
Jay R, Black, Grant, Umeda, Bruce, Dunn, William F, McDonough, Abby, Kavner   +4 more
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Isotope Effect and Isotope Separation: A Chemist's View.

Journal of Nuclear Science and Technology, 2002
What causes the isotope effects (IE)? This presentation will be centered around the equilibrium isotope effects due to the differences in the nuclear masses. The occurrence of the equilibrium constant, K, of isotope exchange reactions which differ from the values predicted by the classical theory of statistical mechanics, Kcl , is explored.
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The Isotope Effect in Superconductivity

Physical Review, 1954
The isotope effect in superconductors is usually summarized by giving the observed values of $p$ in the equation ${M}^{p}{T}_{c}=\mathrm{constant}$, where $M$ is the isotopic mass and ${T}_{c}$ the superconducting transition temperature. Fr\"ohlich predicted the value $p=\frac{1}{2}$, but the measurements in some instances show deviations from this ...
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Isotope Effects in Plasmonic Photosynthesis

Angewandte Chemie, 2020
AbstractThe photoexcitation of plasmonic nanoparticles has been shown to drive multistep, multicarrier transformations, such as the conversion of CO2 into hydrocarbons. But for such plasmon‐driven chemistry to be precisely understood and modeled, the critical photoinitiation step in the reaction cascade must be identified.
Sungju Yu, Prashant K. Jain
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The effect of the thermodynamic isotope effect on the distribution of isotopic molecules

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1961
1. The thermodynamic isotope effect (TIE) may cause the distribution of isotopic molecules to differ substantially from the statistical distribution, especially in the case of light elements. 2. A method is indicated for setting up a system of algebraic equations, the solution of which makes it possible to calculate the concentration of ...
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Isotope effects on isotope effects: equilibrium nitrogen isotope effects on the basicity of pyridine in protium and deuterium oxides

The Journal of Physical Chemistry, 1989
The {sup 14}N/{sup 15}N isotope effect on the pK{sub a} of pyridinium ion is 18% larger in D{sub 2}O than in H{sub 2}O: pK{sub a}{sup 14} {minus} pK{sub a}{sup 15} = {minus}0.0090{sub 7} {plus minus} 0.0001{sub 6} in H{sub 2}O and {minus}0.0107{sub 2} {plus minus} 0.0001{sub 5} in D{sub 2}O.
Joseph L. Kurz, Moheb M. Nasr
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Isotope effects on the crotonase reaction

Biochemistry, 1989
The primary, alpha-secondary, beta-secondary, and beta'-secondary deuterium and primary 18O kinetic isotope effects on V/K for the dehydration of [(3S)-3-hydroxybutyryl]pantetheine by bovine liver crotonase (enoyl-CoA hydratase, EC 4.2.1.17) have been determined by the equilibrium perturbation method.
B J, Bahnson, V E, Anderson
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Deuterium Isotope Effect on Carbon Isotope Fractionation in Photosynthesis

Science, 1967
Plants grown in D 2 O show a decreased tendency to fractionate carbon-13 during photosynthetic incorporation of carbon dioxide. The isotopic ratio C 13 /C 12 of the tissues of deuterated plants appears to be proportional to the deuterium content of the tissue.
R A, Uphaus, J J, Katz
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Isotope Effect in Superconducting Fullerenes

Science, 1992
The effect of isotopic substitution on the superconducting transition temperature, T c , in alkali-doped C 60 has been examined. Paradoxically, it is found that a substantial decrease in T c with the increasing isotopic mass is possible even ...
S, Chakravarty, S A, Kivelson, M I, Salkola, S, Tewari   +3 more
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