ABSTRACT — The Kα X-ray satellite spectra of S and some of its compounds, excited by Rh tube X-rays, are studied with a plane crystal spectrometer.
ABSTRACT —In this paper some measurements on the impedance of aluminium oxynitride samples, using a Fourier technique, are presented and discussed.
ABSTRACT —A molecular dynamics simulation of an ionic system has been done using a method recently suggested by Adams and Dubey for performing Ewald’s summation. The damped force method of Hoover and Evans for simulation in the N, V, T ensemble has also been used.
ABSTRACT — The nature of anisotropy-energy driven spin-reorientation transitions in uniaxial materials has been studied. A simple phenomenological model is developed to describe first and second order transitions for situations where the first two anisotropy constants vary linearly with temperature.
ABSTRACT — The new satellite positioning system, the Global Positioning System (GPS), is having a great impact in solving all problems involving threedimensional position determination, on earth or space, with applications that go beyond Geodesy.
ABSTRACT — The Aeromagnetic Survey of Portugal here presented makes possible a high precision mapping of the magnetic anomalies due to crustal heterogeneities.
ABSTRACT —It is shown that, in the case of rovibrating octahedral molecules, the tensor relating the rotational magnetic moment to the total angular momentum has a simple expression: its nuclear component is a constant and its electronic component is proportional to the tensor ...
ABSTRACT — The mean-field renormalization group method is used to study the effect of the transverse field on the quantum Blume-Capel model; the critical surface in the temperature — crystal field coupling — transverse field space is obtained.
ABSTRACT —he precipitation of the phase α-Fe,O, in glasses of the system x Fe2O3 PbO.2B2O3 depends both on concentration and cooling rate.
ABSTRACT —In an earlier paper (Miranda et al., 1987) we presented the southern panel of the Aeromagnetic Survey of Portugal. With the conclusion of the northern one, here discussed, the survey is accomplished and an accurate mapping of the total magnetic field, for the 1980.0 epoch, is achieved.
ABSTRACT —Asimple model is described which enables preliminary studies of the impact in Portugal of the release of large quantities of carbon dioxide to the atmosphere, due to man-related activities.