Capa
Volume 4 / Fascículo 1-4
1965
Descarregar revista

Portugaliae Physica reaparece após uma interrupção de onze anos. Foi a única revista portuguesa que, até hoje, se consagrou exclusivamente a publicação de trabalhos de investigação cientifica no dominio das Ciéncias Fisicas. Nos trés volumes publicados entre 1943 e 1954 incluiu nas suas páginas notáveis trabalhos da autoria não só de investigadores portugueses mas também de investigadores estrangeiros de diversos centros cientificos.  


RESUME — On montre qu’a l’intérieur d’un faisceau de particules en cours d’accélération dans un accélérateur circulaire dont la h. f. est modulée existent des courants de convection responsables de l’évolution de la densité de répartition des particules dans le faisceau. Cette évolution, qui peut étre regardée comme une illustration d’un probléme célébre déja étudié par Maxwell, tend a rapprocher la composition du faisceau d’une certaine distribution statistique limite.  


RESUME — Le rendement de fluorescence du niveau L du radium, ....


RESUME —Le formalisme du modéle statistique est appliqué a l’étude de la désexcitation des noyaux issus du bombardement de Bi, Au et Tb par des protons d’énergies comprises entre 50 et 155 MeV. 


SUMMARY — A new formula to approach the temperature dependence of the isotopic thermal diffusion factor is proposed. It can be successfully applied to theoretical data of Lennard-Jones (12-6) and Exp.-Six models, as well as to the available observations with isotopes of Ne, Av, Kr, and Xe. This enables us to make a reasonable comparison between theory and experiments, showing that the above models are not satisfactory to explain, simultaneously, thermal diffusion and viscosity data of the referred noble gases.  


ABSTRACT—The Coster-Kronig yield f13 of rhenium (Re) has been determined by comparing the relative intensities of the LX-ray lines with the Lα and Lβ2, satellites. The experimental result is:  


ABSTRACT — The role of water vapor in the energetics of the general circulation of the atmosphere is studied and discussed. The water vapor is the most important absorber of solar energy in the atmosphere, and hence, its distribution influences the form of the energy input into the system. Through the release of latent heat it generates zonal available and eddy available potential energy. The available potential energy of the disturbances is partly supplied by the non adiabatic heating due to condensation. The implications of the meridional transport of latent heat and of its divergence are discussed in the light of various meteorological considerations. 


ABSTRACT — A new method for obtaining a classical collective hamiltonian is presented. The starting point is the many-body hamiltonian and the derivation is based on the variational principle of quantum mechanics. The force and mass parameters are determined without ambiguity by the single particle energies and by some matrix elements of the two-body interaction. The theory is applied to the dipole state of 160. 


RESUME — La premiére partie de cet exposé reprend briévement quelques points de la théorie de la double solution et de la théorie de la fusion de M. Louis de Broglie. On écrit alors les solutions singuli¢res des équations du photon, obtenues par la fusion de deux solutions des équations de Dirac, et on montre que, sous des conditions trés simples, ces solutions obéissent au théoréme du guidage. Dans la derniére partie ces résultats sont illustrés par un exemple.


The σ-phase structure of Cr2Ru has been confirmed by single crystal measurements. Six out of seven parameters have been refined. The distribution of atoms in the available sites appears to be disordered; the ratio of the two atoms is almost the same in the different sites.  


ABSTRACT —The scheme of the levels of Re187 fed by the β-decay of W187 has been investigated. Added to the two transitions of 746 and 880 keV which have been found with GeLi  γ spectrometer, an internal conversion study with 180° magnetic spectrometers equiped with preacceleration shows a number of new transitions. 


RESUME — On examine dans un cas simple sous quelles hypothéses sont énoncées les relations d’Heisenberg. On vérifie qu’à moins d’introduire le postulat du caractére instantané des transitions quantiques, on peut connaitre à la fois et avec précision la position et la quantité de mouvement d’un corpuscule. Il s’ensuit notamment que la formulation causale de la Mécanique ondulatoire n’est pas nécessairement une théorie à paramétres cachés.  


RESUME — Te spectre d’électrons de conversion interne émis au cours de la transmutation  a été étudié selon méthode des plaques nucléaires.


SUMMARY — Isotopic thermal diffusion in neon was observed in the temperature range from 335.6 up to 507.4 °K, which provides a sensitive way to determine the parameter « for the exponential-six model. 


© 2019 Sociedade Portuguesa de Física