The norm game (NG) introduced by Robert Axelrod is a convenient frame to disccuss the time evolution of the level of preserving norms in social systems. Recently NG was formulated in terms of a social contagion on a m...
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The problem of spin-dependent transport of electrons through a metallic nanostructure is considered. The system consists of non-magnetic metal wire with two magnetic impurities and is connected to two ferromagnetic le...
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The problem of spin-dependent transport of electrons through a metallic nanostructure is considered. The system consists of non-magnetic metal wire with two magnetic impurities and is connected to two ferromagnetic leads. The differential conductance is calculated by using the transfer matrix method. The spin polarization of the conductance is also obtained. It was found that this polarization is dependent on the spin configuration of magnetic impurities. This dependence can be controlled by the applied bias voltage.
Ferrous gluconate and antianemic medicament Ascofer® were investigated with Mössbauer spectroscopy in order to determine forms of iron ions present in both types of samples. Room temperature spectra gave a c...
Ferrous gluconate and antianemic medicament Ascofer® were investigated with Mössbauer spectroscopy in order to determine forms of iron ions present in both types of samples. Room temperature spectra gave a clear evidence that two phases of iron were present viz. ferrous (Fe2+) as a major one with a contribution of ~85 ±5 %, and ferric (Fe3+) whose contribution was found to be ~15±5 %. Ferrous ions were shown to occupy at least two different sites.
Nervous system conveys information by electrical signals called `spikes', therefore, spikes detection and sorting are challenging topics in the neural data processing. The principal component analysis (PCA) is a c...
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Nervous system conveys information by electrical signals called `spikes', therefore, spikes detection and sorting are challenging topics in the neural data processing. The principal component analysis (PCA) is a convenient tool for clustering spikes; however it has some disadvantages for closely shaped and overlapped spikes. For such the cases, an algorithm based on the combination of the principal component analysis and undecimated wavelet transform, is proposed to enhance the cluster formation from the spikes mapping. These results indicate that the principal component analysis used in combination with the undecimated wavelet has a better performance in the spike sorting. This can lead to more compact and separate clusters in comparison with the PCA clustering and more efficient spike sorting.
We present the test results of the ABCN-25 front end chip implemented in CMOS 0.25 μm technology and optimised for the short, 2.5 cm, silicon strips intended to be used in the upgrade of the ATLAS Inner Detector. We ...
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ISBN:
(纸本)9789290833352
We present the test results of the ABCN-25 front end chip implemented in CMOS 0.25 μm technology and optimised for the short, 2.5 cm, silicon strips intended to be used in the upgrade of the ATLAS Inner Detector. We have obtained the full functionality of the readout part, the expected performance of the analogue front-end and the operation of the power control circuits. The performance is evaluated in view of the minimization of the power consumption, as the upgrade detector may contain up to 70 million of channels. System tests with different power distribution schemes proposed for the future tracker detectors are possible with this chip. The ABCN-25 ASIC is now serving as the prototype readout chip in the developments of the modules and staves for the upgrade of the ATLAS Inner Detector.
Hydrogenation effects on crystalline and magnetic structure of nanocomposites (FeCoZr) x (Al2O3) 100-x, 38 le;x≤63 at.% are studied by 57Fe Mössbauer spectroscopy and magnetometry. Variations of local structure,...
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The galvanomagnetic and thermoelectric properties including Hall effect, electrical resistivity, thermopower, and thermal conductivity have been studied for polycrystalline Mo3Sb7. The temperature dependences of the v...
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The galvanomagnetic and thermoelectric properties including Hall effect, electrical resistivity, thermopower, and thermal conductivity have been studied for polycrystalline Mo3Sb7. The temperature dependences of the various physical properties, measured from 2 up to 800 K, was explained supposing an important role of magnetic fluctuations significantly suppressed by the opening of a gap in the spin excitation spectrum. In addition, we propose that magnetic excitations are likely responsible for the exotic temperature dependence of the thermal conductivity in the whole temperature range. The high value of the dimensionless figure of merit ZT achieved at high temperature classifies this p-type metal as one of the best thermoelectric metal discovered up to now.
The galvanomagnetic, thermoelectric, and magnetic properties of some polycrystalline Mo3Sb7−xTex compounds (x=0.0, 0.3, 1.0, 1.6, and 2.2) have been experimentally investigated from 2 to 350 K. These samples were prep...
The galvanomagnetic, thermoelectric, and magnetic properties of some polycrystalline Mo3Sb7−xTex compounds (x=0.0, 0.3, 1.0, 1.6, and 2.2) have been experimentally investigated from 2 to 350 K. These samples were prepared via a metallurgical route, and characterized by x-ray diffraction and electron probe microanalysis. Experiments were completed by theoretical information including dispersion curves, and total and partial densities of states within the framework of the Korringa-Kohn-Rostoker method with the coherent-potential approximation. These theoretical aspects have highlighted a shift of the Fermi level toward the valence-band edge with increasing x that can be understood within a rigid-band model. Transport property measurements have not only provided compelling evidence for this picture but have also shown that their variations with the Te content is consistent with a progressive crossover from a metalliclike to a semiconductinglike state as theoretically suggested. The enhancement of the thermal conductivity as x increases constitutes one of the most impressive properties of this system. This surprising behavior is tentatively ascribed to the disappearance of a strong scattering of phonons by magnetic excitations displayed by Mo3Sb7. The compositional evolution of the magnetic properties has brought further evidence of a progressive suppression of these magnetic excitations as the Te concentration increases. In addition, magnetic susceptibility together with specific-heat measurements have confirmed the decrease in the total density of states at the Fermi level with x suggested by our band-structure calculations.
Electrical and thermal transport properties, including thermopower, electrical resistivity, thermal conductivity, as well as Hall effect and magnetic susceptibility measurements have been carried out on polycrystallin...
Electrical and thermal transport properties, including thermopower, electrical resistivity, thermal conductivity, as well as Hall effect and magnetic susceptibility measurements have been carried out on polycrystalline Mo3−xRuxSb7 samples for nominal concentrations x=0.0, 0.25, 0.50, and 1.0 in the 2–350 K temperature range. Further insight into the variations in the electronic band structure as the Ru content increases has been gained by calculating dispersion curves and total and partial densities of states using the Korringa-Kohn-Rostoker method with the coherent-potential approximation. This theoretical analysis has revealed a rigidlike behavior of the electronic structure, synonymous of a shift in the Fermi level toward the valence band edge as x increases. Transport properties investigations have provided compelling experimental evidence for this picture, i.e., an increase in both the electrical resistivity and thermopower which is concomitant to a decrease in the charge-carrier concentration with x. Magnetic susceptibility data have shown that the magnetic interactions displayed by Mo3Sb7 are progressively suppressed by increasing the ruthenium concentration. In addition, increasing x leads to a surprising enhancement of the lattice thermal conductivity that may be due to the suppression of strong phonon-dimer interactions exhibited by Mo3Sb7.
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