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991.
J. Migdałek R. Marcinek 《Journal of Quantitative Spectroscopy & Radiative Transfer》1984,32(4):269-277
The 4fn6s2?4fn6s6p transitions are studied for neutral samarium, europium, dysprosium, erbium, and ytterbium. Four different couplings between the valence electrons and the 4fn shell are considered, three are based on the LS and one on the JIJII scheme. The radial integrals are computed with the model-potential method, which includes both exchange and core polarization. The results are compared with those obtained by employing the Coulomb approximation and the ab initio Hartree + Exchange (HX) approach, as well as with available experimental data. The core-polarization influence on oscillator strengths for these transitions is also investigated. 相似文献
992.
Jan J. Sławianowski 《International Journal of Theoretical Physics》1975,12(4):271-296
The mechanics of an affinely-rigid body is investigated on both the classical and the quantum level. An affinely-rigid body is defined as a system of material points or a continuous medium in which all affine relations are frozen. Our treatment is based on the general theory of systems with closed teleparallelisms, presented in Section 2 of this paper. 相似文献
993.
Osmotic coefficients measured by vapour pressure osmometry are reported for benzene solutions of complexes of pyridine with trifluoroacetic, dichloroacetic and chloroacetic acids at 25°C. Solute activities decrease with increasing concentration due to formation of self-associates. It is suggested that dipole-dipole interactions contribute substantially to the stability of the associates. 相似文献
994.
995.
996.
997.
Roman Słowinski 《European Journal of Operational Research》1981,7(3):265-273
The paper deals with the allocation of different categories of resources in a network project under multiple conflicting criteria including project duration or maximum lateness, and several cost criteria. The resource requirements of the splittable activities are assumed to be discrete, i.e., assuming arbitrary values from given finite sets for particular resource types and categories. Two approaches for solving the problem, using multiobjective linear programming in specific ways, are described. Reduction of the number of activity preemptions, as a secondary project performance measure, is considered. 相似文献
998.
Bronisław Kuchowicz 《General Relativity and Gravitation》1974,5(2):201-234
The three subsequent levels of approach to the problem of the neutrino in general relativity which have been exploited till now, are:
- ‘classical particle’ approach, i.e. a study on the neutrino as a classical particle in a classical, given gravitational field;
- ‘quantum particle’ approach, i.e. considering the Dirac equation for the neutrino in a given gravitational field;
- ‘classical field’ approach comprising the study of combined neutrino-gravitational fields.
999.
1000.
A. Budzanowski K. Chyla R. Czabański K. Grotowski L. Jarczyk B. Kamys A. Kapus̀cik S. Micek J. Płoskonka A. Strzałkowski J. Szmider Z. Wróbel L. Zastawniak R. Zybert 《Nuclear Physics A》1973,211(3):463-472
Excitation functions for the elastic scattering of α-particles from Ni, Co and Cu at θlab = 179° were measured in the lab energy range 22.75–28.40 MeV, as well as some angular distributions for Co(α, α). Broad maxima with a width of about 2.5 MeV were found in the excitation functions. It is shown that a simple four-parameter optical model of the interaction is able to reproduce the angular distributions as well as the excitation functions. Examination of the Argand diagrams leads to the conclusion that the maxima in the excitation curves are formed as a result of a coherent superposition of a number of partial waves, none of which behaves in itself in a resonance-like manner. 相似文献