Results 281 to 290 of about 101,916 (337)

Kinetic hydrogen isotope effect

Journal of Chemical Education, 1986
This note describes three simple demonstrations or laboratory exercises that illustrate kinetic hydrogen isotopic effects.
David A. Binder, Robert Eliason
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On the kinetic isotope effect in cracking

The International Journal of Applied Radiation and Isotopes, 1959
Resume On decrit des recherches sur l'effet kinetique des isotopes dans la degradation du C 14 H 3 -C 14 H 3 et du C 14 H 3 -C 14 H 3 . Les resultats obtenus sont d'accord avec l'hypothese propose sur l'effet que prete la symetrie aux taux de decomposition.
R. A. Kalinenko, K. P. Lavrovsky, A. M. Brodsky   +2 more
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Kinetic Isotope Effect [PDF]

, 2014
Molecules with different isotopic compositions generally react with other molecules in the same manner, but their reaction rates show differences due to their mass differences and sometimes also due to the lower natural abundance of certain isotopes. For example, CO2 is heavier than CO2 by about 2.3 %, and the abundance ratio of CO2/ CO2 is about 1.1 %.
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Isotope Effects in Chemical Kinetics

Annual Review of Physical Chemistry, 1975
Recent studies on hydrogen isotope transfer reactions in the gas phase chemistry of thermal and excited species, ionic systems, and reactive scattering and theoretical attempts made to rationalize experimental observations are critically reviewed. Topics discussed are bimolecular reactions, termolecular reactions, unimolecular decomposition reactions ...
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Kinetic isotope effect in hydrolysis of bisdiazoketones

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1984
In the hydrolysis of bisdiazoketones in aqueous HClO4 solutions the step of protonating the starting compounds is not the limiting step; differences in the reactivity of the disdiazoketones is apparently related to the variable decomposition rate of the formed diazonium ions.
L. I. Kirkovskii, V. G. Kartsev, A. M. Sipyagin   +2 more
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Equilibrium and kinetic isotope effects

Berichte der Bunsengesellschaft für physikalische Chemie, 1972
AbstractThe equilibrium distribution effects of deuterium and of tritium between liquid water, hydrogen gas and palladium hydride differ from one another in a characteristic manner. They are discussed in terms of zero point energies.Direct measurements of the deuterium distribution between liquid water and palladium hydride yielded an uncommonly high ...
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Kinetic-isotope effects in thermal explosions

Thermochimica Acta, 1982
Abstract Kinetic-isotope effects can be used to detect the specific functional groups involved in the elementary reactions of complex explosives decomposition processes. Isothermal kinetics methods must be used to correlate component reactions with specific reaction regimes.
M. H. Ebinger, J. L. Janney, R.N. Rogers
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Temperature Dependences of Kinetic Isotope Effects

The Journal of Chemical Physics, 1971
Model-reaction calculations are used to investigate the expected incidence of temperature-dependence anomalies produced by the harmonic-vibrational contributions to kinetic isotope effects. These “anomalies” are defined as deviations from a smooth-monotonic log–log plot of isotopic rate-constant ratio vs temperature. Such deviations include inflections,
P. Christian Vogel, Marvin J. Stern
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Kinetic isotope effect in the chlorination of methane

Reaction Kinetics and Catalysis Letters, 1975
The ratio of the rate constants has been measured for the reaction of atomic chlorine with CH4 and CD4 within the temperature range 163–613 K. At low temperatures (163–300 K) the ratio is 2.2 exp (1180/RT). The pre-exponential factor of 2.2 agrees with that calculated by transition state theory.
V. N. Panfilov, V. P. Strunin, N. K. Serdyuk, E. N. Chesnokov   +3 more
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Interpretation of Transient-State Kinetic Isotope Effects

Biochemistry, 1996
In contrast to steady-state kinetic isotope effects (KIE's), transient-state KIE's are dependent on both time and signal source. We developed a theory which predicts the behavior of transient-state KIE's, permits the calculation of the intrinsic KIE, and makes possible the assignment of various optical signals to either pre- or post-hydride transfer ...
Harvey F. Fisher, Swapan K. Saha
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