Volume 10 / Fascículo 1-4
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We wish to discuss the equivalence between the Generator Coordinate Method [1] (GCM) and Quantum Fluid Dinamics (QFD). 

ABSTRACT — More than 300 electromagnetic transitions in 28Si, concerning levels with well known Jπ and T are classified according to their character and strength and examined from a statistical point of view. Reliable upper limits are obtained for the transition strengths, based upon a quantitative criterion and useful as spectroscopic tools. Isospin selection rules for dipole and electric quadrupole radiation in self-conjugate nuclei are studied in 28Si. Preferential decay to highly excited energy states is found to be a characteristical feature of this nucleus. 

ABSTRACT — The use of the Doppler Shift Attenuation Method (D.S.A.M.) in nuclear lifetime measurements is briefly described for the typical L.F.E.N, experimental conditions. 

ABSTRACT — The results of experiments on the ionization of thermal beams of Sodium and Potassium atoms by polycrystalline Iridium are presented. From the experiments we determine the work function of Iridium-to be 5,384 +/- 0.07 eV. 

Raman bands assigned to internal vibrations of cation hydrates in concentrated aqueous solutions of aluminium chloride [1] were investigated. The author considered, in the bulk of a concentrated aqueous solution, cation hydrates with a (defined) structure independent of the anion in order to calculate the isotopic shift of these bands when the ordinary water, in the solution, is replaced by deuterium oxide. No coupling of the internal vibration of the water molecule with the oscillations of the hydration complex was noticed in liquid solutions. 

The existence of correlations of positions taken up by heavy ions in aqueous solutions was demonstrated using X-ray diffraction [1]. The existence of a (local) arrangement of hydrated light ions in concentrated electrolytic solutions was suggested [2] [3] for interpreting similar X-ray diffraction experiments; some of those cation hydrates have a defined structure.  

ABSTRACT — Accurate measurements of the thermoelectric power (S) of antiferromagnetic Cr-Al dilute alloys are presented over a wide range of temperature (80-350 K). 

ABSTRACT — The magnetic properties of many Rare Earth compounds can be understood in terms of a crystal field and an exchange interaction. We give an account of the calculation of the direction’of magnetization and crystalline electric field in NdA12. The exchange interaction in this compound is expressed by means of an isotropic molecular field proportional to the magnetization.  

ABSTRACT — Very accurate data on the thermoelectric power (S) and the temperature derivative dS/dT have been obtained for a set of poly-and monocrystalline ferromagnetic Tb-Gd alloys (80-340 K). 

ABSTRACT — The concentrations of three major elements and fourteen trace elements in selected sherds of Iron Age and first century A.D. fine grey ceramics, found at five different archaeological sites in Portugal, were determined by instrumental neutron activation analysis. 

ABSTRACT—Gamma ray-spectrometry has been used in qualitative and quantitative analysis of uranium ores. However till recently only Nal (TI) detectors were used and due to the complexity of the spectra this was a great limitation. 

ABSTRACT — An extension of the Buttle and Goldfarb formalism for heavy ion transfer reactions is presented where recoil effects are considered using the local momentum approximation and the transition amplitude retains the structure of the zero range approximation. The reliability of the method was tested with numerical calculations which take a very small computing time compared with full finite range calculations.  

ABSTRACT — We present some preliminary results concerning the application of a relativistic model to the psi-family. This model differs from a previous one, based on the Bethe-Salpeter equation in instantaneous ladder approximation, in that it includes an anomalous magnetic moment at the quark-gluon vertex. 

ABSTRACT — By means of a (p, p’e ) coincidence experiment a previously reported EQ decay can be assigned to a level at 1592 keV in 102Pd.

ABSTRACT — The nonradiative energy transfer efficiency from pyrene to 9,10 diphenyl anthracene dissolved in benzene is shown to depend on pyrene concentration assuming that the transfer takes place only from the excited pyrene monomer. 

ABSTRACT — The results obtained for fluorescence emission from solutions of pyrene (Py) and 9,10 diphenyl anthracene (DPA) in benzene containing oxygen at atmospheric pressure and excited under steady-state conditions with u.v. light were analysed to get information about the quenching effect of oxygen on pyrene excited monomer. 

ABSTRACT — It has been predicted that the twist viscosity  ...

ABSTRACT — The results and interpretation of magnetization measure- ments made on superconducting multifilamentary Nb3Sn, obtained by the bronze route, are presented. 

ABSTRACT —Thermostatics may be based on the following principle of equilibrium [1,5]: Thermodynamic systems choose for equilibrium state that which minimizes the internal energy. 

ABSTRACT — lon exchange fabrication of low loss waveguides in glass has been demonstrated using Li2SO4— K2SO4 eutectic. The process is extremely fast and the resulting distribution can be controlled by application of an electric field.  

ABSTRACT — Planar optical waveguides, suitable for light-propagation can be used for self-imaging. The formation of one-dimensional self-images is demonstrated experimentally in solid waveguide slabs of homogenous refrac- tive index. 

ABSTRACT — Considering the experimental difficulty in determining the ion temperature of a plasma, namely at high pressures or high temperatures, this work aims at a theoretical determination of the ionic temperature (Ti ) of an Argon plasma in a supposedly homogeneous region where the distribution functions of the electrons (e), ions (i) and neutrals (0) are assumed to be Maxwellian. 

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