Results 221 to 230 of about 25,816 (271)
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A tracer study with O18 in Photosynthesis by activation analysis
The International Journal of Applied Radiation and Isotopes, 1957A method has been devised for tracer studies with oxygen using paper chromatography and proton activation of O/sup 18/ to F/sup 18/. This technique is relatively simple and can detect a fraction of a mu g of O/sup 18/, as well as giving some information about the chemical nature of the compound into which it is incorporated.
I, FOGELSTROM-FINEMAN +3 more
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Nuclear Physics, 1965
Abstract The low-lying even-parity energy levels of O 18 are calculated within the shell model. Core excitations from the double closed O 16 system have been taken explicitly into account using the SU 3 coupling scheme. The resulting energy spectrum shows nice agreement with experiments for nearly all states below 6 MeV excitation energy.
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Abstract The low-lying even-parity energy levels of O 18 are calculated within the shell model. Core excitations from the double closed O 16 system have been taken explicitly into account using the SU 3 coupling scheme. The resulting energy spectrum shows nice agreement with experiments for nearly all states below 6 MeV excitation energy.
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The O18-abundance in fresh water
Geochimica et Cosmochimica Acta, 1954Fresh water of various origins as distinct from ocean water shows great variations in O18-abundance. Proceeding from the temperate towards the colder climates a considerable decrease is noticeable. It is demonstrated that the O18-abundance in atmospheric water vapour is dependent on (a) the precipitation temperature, (b) the origin of the vapour and
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Geochimica et Cosmochimica Acta, 1974
The volcanic rocks of Iceland are anomalous in their oxygen isotope content. Recent tholeiitic and transitional alkali basalts from Iceland range in (δO18 from 1·8 to 5δ7%. Most of the tholeiitic basalts and their phenocrysts are at least 1% lower in δO18 than unaltered basalts from other oceanic islands or oceanic ridges.
Karlis Muehlenbachs +2 more
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The volcanic rocks of Iceland are anomalous in their oxygen isotope content. Recent tholeiitic and transitional alkali basalts from Iceland range in (δO18 from 1·8 to 5δ7%. Most of the tholeiitic basalts and their phenocrysts are at least 1% lower in δO18 than unaltered basalts from other oceanic islands or oceanic ridges.
Karlis Muehlenbachs +2 more
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An application of the separation method in O18 and Ne20
Nuclear Physics, 1964Abstract The low-lying energy levels of O18 and Ne20 are calculated with a well-behaved force of Yukawa type and with a hard core force, both of which fit the low-energy properties of the free two-body system. For the latter one a Scott-Moszkowski separation method is used and only the long-range part of the force is included in the calculations.
T. Engeland, A. Kallio
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Energy levels of O18 with separable potential
Nuclear Physics, 1965Energy levels of O18 have been calculated for a non-local separable potential using the reaction matrix of Brueckner's theory of the many-body problem. Only 2s12 and 1d52 configurations have been considered. The order of the levels is in agreement with the experimental spectrum.
V.L. Narasimham, S.K. Shah
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Lithos, 1968
The positional and thermal parameters of synthetic forms of hydrous beryl and emerald and of anhydrous beryl and emerald were refined by least-squares and difference Fourier methods using 3D data recorded with a counter diffractometer. The mean Be−O and Si−O bond distances determined for the four crystals are statistically identical and measure on the
G.V. Gibbs, D.W. Breck, E.P. Meagher
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The positional and thermal parameters of synthetic forms of hydrous beryl and emerald and of anhydrous beryl and emerald were refined by least-squares and difference Fourier methods using 3D data recorded with a counter diffractometer. The mean Be−O and Si−O bond distances determined for the four crystals are statistically identical and measure on the
G.V. Gibbs, D.W. Breck, E.P. Meagher
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Nuclear Physics, 1963
Abstract Differential cross-sections and proton-gamma-ray angular correlation functions in the reaction plane at six different proton angles, have been measured for the O 16 (t, pγ) O 18 reaction through the first excited state (1.98 MeV) of O 18 , using tritons of energy 5 MeV.
F.H. Read, J.M. Calvert
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Abstract Differential cross-sections and proton-gamma-ray angular correlation functions in the reaction plane at six different proton angles, have been measured for the O 16 (t, pγ) O 18 reaction through the first excited state (1.98 MeV) of O 18 , using tritons of energy 5 MeV.
F.H. Read, J.M. Calvert
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A method for the determination of the O18 concentration of the oxygen of organic compounds
The International Journal of Applied Radiation and Isotopes, 1956Oxygen-containing organic compounds can be oxidized to yield CO2 by HgCl2 (or Cu2Cl2 or Cl2) at 360–530°C. The carbon dioxide formed in this reaction has the same O18 concentration as the original compound. This procedure has been tested and found to give the correct result on glucose, arginine, phenylalanine, tyrosine, benzamide, N-dinitrophenyl ...
L, PONTICORVO, D, RITTENBERG
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Das Atomgewicht des Sauerstoffisotops O18
Zeitschrift f�r Physik, 1930Mit Hilfe einer genauen bandenspektroskopischen Untersuchung der atmospharischen Sauerstoffbanden (sogenannte A- und A′-Gruppe bei λ 7600) gelingt es, unter Zugrundelegung eines Normalgewichts von 16,000 fur O16 das Atomgewicht des Sauerstoffisotops O18 zu 17,991 ± 0,010 zu bestimmen.
R. Mecke, K. Wurm
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