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91.
C. E. Violet R. J. Borg Leopold May K. V. Rao J. Nogues R. D. Taylor A. P. Batra 《Hyperfine Interactions》1988,42(1-4):963-966
The magnetic properties of two amorphous Fe?Ni?Zr alloys, Fe89.7Ni0.03Zr10 and Fe70Ni20Zr10, both in the “as cast” and neutron irradiated states were investigated by Mössbauer spectroscopy and dc magnetic susceptibility measurements. The upper magnetic ordering temperatures of Fe89.7Ni0.03Zr10 are 232K and 246K for the “as cast” and irradiated samples, respectively. The magnetic ordering temperature for Fe70Ni20Zr10 was about 478K for both the “as cast” and irradiated samples. Both compositions yield magnetic hyperfine spectra, which show a considerable relaxation effect that must be explicitly considered in the calculation of the average local Fe moments. When this is done, these values derived from Mössbauer spectra are in good agreement with the dc susceptibility values. The effects of neutron irradiation on the magnetic properties of these alloys are small. 相似文献
92.
The densities of the pure organic liquids: cyclohexane, nitrobenzene, 1-hexanol, 1-octanol, 1-decanol, and 1-dodecanol have been measured with an accuracy of 10–5 g/cm3 using the mechanical oscillator technique. The results were compared to the values given in the literature. From the measured densities the coefficients of thermal expansion were calculated.
Mit 1 Abbildung 相似文献
Mit 1 Abbildung 相似文献
93.
Nicolae Popa 《Archiv der Mathematik》1978,30(1):62-66
Sans résumé 相似文献
94.
Tertiary amine oxides catalyze a variety of phase transfer reactions, primarily by deoxygenation to form the tertiary amine or derived catalyst. 相似文献
95.
In this article we give a complete global classification of the class QSess of planar, essentially quadratic differential systems (i.e. defined by relatively prime polynomials and whose points at infinity are not all singular), according to their topological behavior in the vicinity of infinity. This class depends on 12 parameters but due to the action of the affine group and re-scaling of time, the family actually depends on five parameters. Our classification theorem (Theorem 7.1) gives us a complete dictionary connecting very simple integer-valued invariants which encode the geometry of the systems in the vicinity of infinity, with algebraic invariants and comitants which are a powerful tool for computer algebra computations helpful in the route to obtain the full topological classification of the class QS of all quadratic differential systems. 相似文献
96.
97.
The frequency of radiation from Ta(superconducting)-Al(normal) point contacts has been measured as a function of temperature. The dependence agrees with the Bardeen-Cooper-Schrieffer (BCS) gap equation for Ta. 相似文献
98.
We study the parity-violating neutral current effects in muonic atoms which might result from an interference between E1 and E2 amplitudes in 3D → 1S transitions. We conclude that polarization asymmetries may be measurable in heavy atoms (Z ~ 70) exhibiting large nuclear deformations. 相似文献
99.
Characteristics of p-terphenyl and PBD, the most efficient uv dyes, have been investigated under high intensity pumping by a multi-atmosphere KrF1 discharge laser at 248 nm wavelength. Energy conversion efficiencies, spectral features and temporal behaviour of the dyes were studied parametrically. A maximum powerof 2 MW uv emission with a bandwidth of ~2×10-2 nm was obtained for PBD. It was found that a mixture of both dyes provided higher (by a factor of 1.3) output in the range 348–366 nm than either of the dyes alone. Significant pump intensity dependent conversion efficiency and pulse shape variations were observed for the most efficient uv dye, p-terphenyl and were related to triplet-triplet adsorption processes in the dye. 相似文献
100.
Leopold Laitem Leon Christiaens Marcel Renson 《Magnetic resonance in chemistry : MRC》1980,13(5):319-322
An important 13C NMR shielding effect on carbons bearing a heavy chalcogen is demonstrated. This effect is parallel to that induced by iodine, but to a lesser extent. For acyclic compounds and for partially saturated heterocycles, there is an excellent linear correlation between the 13C chemical shifts of carbons bearing a chalcogen and carbons bearing a halogen atom in the corresponding compound. The linearity of the relationship is less satisfactory with heteroaromatic compounds. 相似文献