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991.
G. A. Timmer F. Meurders P. J. Brussaard J. F. A. van Hienen 《Zeitschrift für Physik A Hadrons and Nuclei》1978,288(1):83-96
Electromagnetic transition rates and logft values were calculated for transitions between positive-parity states in theA=24?28 mass region. The wave functions used were taken from a previous paper. In general we found satisfactory agreement with experiment. In order to have a measure of the stability of the results against changes in the Hamiltonian a method was developed for assigning errors to calculated transition properties. The renormalized single-particle matrix elements of theE2 andM 1 transition operators were determined in a phenomenological way. To this end use was made of the errors just mentioned. It was found that good agreement was obtained with bare-nucleonM 1 singleparticle matrix elements and a state independent effective isoscalar charge for theE 2 operator. Predictions for static moments are given. 相似文献
992.
Summary An apparatus is described for the determination of hydrogen and deuterium in zircaloy by vacuum extraction at 1000–1100 C and mass spectrometry. The procedure is given in detail and items like blanks, sensitivity, reproducibility, and isotope effects are discussed.
Bestimmung von Wasserstoff und Deuterium in Zircaloy durch Vakuumextraktion und Massenspektrometrie
Zusammenfassung Eine apparative Anordnung zur H- und D-Bestimmung in Zircaloy durch Vakuumextraktion bei 1000–1100° C und anschließende massenspektrometrische Messung wird beschrieben. Blindwerte, Empfindlichkeit, Reproduzierbarkeit und Isotopeneffekte werden diskutiert.相似文献
993.
We report two-pulse photon echo decay and free induction decay measurements of iodine as a function of noble-gas pressure. The non-exponential behavior of the two-pulse photon echo decay which in contrast to the free induction decay shows a t3 dependence, is extensively discussed. A comparison with the results of the three-pulse stimulated echo measurements is made. The results are interpretated in terms of a quantum mechanical transport equation, and analytical expressions are derived for the three-pulse stimulated echo, two-pulse echo and free induction decay. 相似文献
994.
995.
van Tilborg Henk C.A. 《Discrete Mathematics》1981,33(2):197-207
Let n(k,d) denote the smallest value of n for which a binary (n,k,d) code exists. Then n(k, d) was known for all d, when k ?6. All values of n(7, d) will now be presented. 相似文献
996.
The compound YNi3 () is ferromagnetic below Tc = 35 K. After hydrogen absorption it loses its ferromagnetic character and becomes Pauli paramagnetic. The composition of the ternary hydride is approximately YNi3H4. The lattice constants are , . 相似文献
997.
E. W. C. van Groesen 《Flow, Turbulence and Combustion》1981,37(1-2):53-65
998.
999.
J. van der Hurk Tj. Hollander C.Th.J. Alkemade 《Journal of Quantitative Spectroscopy & Radiative Transfer》1974,14(11):1167-1178
Experiments are described to yield more decisive information about the excitation energies of visible strontium monohydroxide bands appearing in flames. Excitation energy differences are derived directly from the ratio of thermal band intensities measured as a function of temperature. Absolute excitation energies are derived from the temperature dependence of the ratio of thermal band to strontium line intensity, while assuming a value for the dissociation energy of SrOH. Flames with temperatures ranging from 1907 to 2886 K were used. A level diagram is proposed for the strontium bands at 6060, 6470, 6690, and 6820 Å. From the results obtained, two conclusions may be drawn: (i) the bands considered are non-resonance bands and (ii) the uncertainty in the excitation energy as a result of the unknown molecular configuration is 0·25 eV. 相似文献
1000.
It is demonstrated that the isomer shift of Mössbauer nuclei in transition metal alloys can be quantitatively described in terms of an atomic cell model. The isomer shift ΔE, relative to the pure metal as a reference, is derived from a change in boundary conditions for the atomic cell; , where ø1 is the electronegativity parameter, nws the cell boundary electron density and P and Q are constants for a given Mössbauer nucleus. For solid solutions there is in addition a relatively small size mismatch term. 相似文献