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991.
Analysis of the γ-ray angular distributions measured at 16 36S(p, γ)37Cl resonances yields the spins and/or parities of 21 bound states of 37Cl in addition to the resonance spins. Among the latter are four resonances. For several other bound states the possible spins have been restricted. Multipolarity mixing ratios have been deduced from the same data. Lifetimes (or lifetime limits) of 29 bound states have been deduced from DSA measurements.This extensive experimental information allows a comparison with the results of a shell-model calculation for both the even- and odd-parity states of 37Cl. In this calculation either zero, one or two particles are promoted from the 2s or 1d to the 1f or 2p subshells. Up to an excitation energy of about 5 MeV a one-to-one correspondence is found between experimental and calculated levels. 相似文献
992.
993.
A further analysis of previous reported measurements of dielectric relaxation losses in lead chloride and lead bromide crystals shows that the dipoles may occupy several energetically different positions, giving rise to localization of the dipoles and anomalous behaviour of the susceptibility. This energy difference is determined. Inspection of the crystal structure shows that the anion vacancy, being the mobile part of the dipole (which is an associate like (MePb·VX)x or (OX·VX)x where X = Cl, Br), may jump indeed between halide ion sites with different coordination number.A comparison between the dipole concentration as calculated from the observed losses and the associate concentration as estimated from ionic conductivity experiments leads to the conclusion that local field corrections in the calculations are important. 相似文献
994.
An important limitation to the sensitivity of analytical methods using atomic spectroscopy is the short residence-time of the atoms in the light-path. The possibility has been studied of sealing the samples in a quartz tube where they are forced to emit light by microwave excitation. The detection of amounts below one ng in a volume of 0.5 ml seems possible. 相似文献
995.
996.
997.
Ohne Zusammenfassung 相似文献
998.
S.M. van der Kerk A.L.M. van Eekeren G.J.M. van der Kerk 《Journal of organometallic chemistry》1980,190(1):C8-C10
The synthesis of alkyl-substituted 1,4-dimethyl-1,4-diboracyclohexa-2,5-dienes from dialkylacetylenes and the system C8K/MeBBr2 is described. 相似文献
999.
It is shown that Polo's method for the calculation of the D?1 and G?1 matrices can be extended to the calculation of the absolute rotational contributions involved in the molecular dipole moment derivatives in terms of symmetry coordinates. The method applies to both stretching and bending modes. The method is outlined for AB3 (C3v) molecules. 相似文献
1000.
Selected ortho-disubstituted pyridines and thiopenes react with Michael acceptors to give functionalized quinolines or benzo[b]thiopenes, respectively. 相似文献