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Assessment of the ozone isotope effect
2005This series, established in 1965, is concerned with recent developments in the general area of atomic, molecular and optical physics. The field is in a state of rapid growth, as new experimental and theoretical techniques are used on many old and new problems.
Mauersberger, K. +3 more
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Measurement of Enzyme Isotope Effects
2017Enzyme isotope effects, or the kinetic effects of "heavy" enzymes, refer to the effect of isotopically labeled protein residues on the enzyme's activity or physical properties. These effects are increasingly employed in the examination of the possible contributions of protein dynamics to enzyme catalysis.
Svetlana A, Kholodar +2 more
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Observation of Isotope Effects in Sonoluminescence
Physical Review Letters, 1995The spectrum of sonoluminescence emitted by single bubbles of H{sub 2}, D{sub 2}, He{sup 3}, and He{sup 4} trapped in H{sub 2}O and D{sub 2}O has been measured. We find that heavy water has a dramatic effect on the spectrum of hydrogenic gases, yielding a blackbody-type spectrum with a spectral peak at about 400 nm.
, Hiller, , Putterman
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A New Form of Kinetic Isotope Effect. Dynamic Effects on Isotopic Selectivity and Regioselectivity
Journal of the American Chemical Society, 2003The intramolecular H/D kinetic isotope effect in the ene reaction of singlet oxygen with tetramethylethylene is studied using quasiclassical direct dynamics calculations on a B3LYP/6-31G* potential energy surface. Starting from the area of the energy surface around a valley-ridge inflection point, random trajectories lead to predominantly H abstraction
Daniel A, Singleton +3 more
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Deuterium Isotope Effects in Cytology
1965Publisher Summary This chapter focuses on the growth characteristics of microorganisms and higher plants in deuteriated media and on the cytology of deuteriated cells. Deuteriated microorganisms exhibit a less well-organized pattern than do ordinary microorganisms. The degree of structural disorder is at a minimum in fully adapted cells, perhaps as a
E, Flaumenhaft +3 more
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Mass-Independent Isotope Effects
The Journal of Physical Chemistry B, 2013Three fundamental properties of atomic nuclei-mass, spin (and related magnetic moment), and volume-are the source of isotope effects. The mostly deserved and popular, with almost hundred-year history, is the mass-dependent isotope effect. The first mass-independent isotope effect which chemically discriminates isotopes by their nuclear spins and ...
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The secondary hydrogen isotope effect
The International Journal of Applied Radiation and Isotopes, 1960Abstract Secondary isotope effects are reviewed with particular regard to their interpretation within a consistent scheme. It appears that adherence to formal considerations of vibrational frequency shifts is inadequate for the interpretation of many experimental results, and that these may be more fruitfully discussed in terms of “electronic ...
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Isotope Effects on Nuclear Shielding
Progress in Nuclear Magnetic Resonance Spectroscopy, 1984Publisher Summary Isotope effects have been known for a long time and an excellent review covering the early reports exists. The magnitude of the isotope shift is generally dependent on how remote the isotope substitution is from the nucleus under observation.
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Mechanism from Isotope Effects
Isotopes in Environmental and Health Studies, 1998Abstract Isotope effects represent perhaps one of the most versatile tools available to investigators interested in the determination of reaction mechanism, particularly in the case of the mechanistic enzymologist. Interpretation of isotope effect data is somewhat more difficult for enzyme reactions, since the chemical or isotope-dependent step(s) is(
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