Kinetics of the α- to σ-phase transformation in an equiatomic Fe-V alloy has been studied by Mössbauer Spectroscopy and X-ray diffraction. The B2 superstructure seems to form prior to the precipitation of the ...
Kinetics of the α- to σ-phase transformation in an equiatomic Fe-V alloy has been studied by Mössbauer Spectroscopy and X-ray diffraction. The B2 superstructure seems to form prior to the precipitation of the σ-phase. The results obtained in this study give evidence that in the investigated interval, the transformation kinetics strongly depends on temperature. The kinetics of the α- to σ-phase transformation, as determined from the temperature dependence of the average hyperfine field derived from the Mössbauer spectra, has been quantitatively described in terms of the Johnson-Mehl-Avrami equation, from which the kinetics parameters n and k have been determined.
This paper deals with a computer-aided distributed design system based on hypergraph grammars and cooperating agents. Hypergraph grammars are used to generate structures of designs in the form of specific graphs allow...
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In the paper we present a design of the circuit for recording and processing electrical signals from alive neural tissue using multi-electrode arrays. The design is optimised with respect to critical requirements for ...
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In the paper we present a design of the circuit for recording and processing electrical signals from alive neural tissue using multi-electrode arrays. The design is optimised with respect to critical requirements for such circuits, i.e. low noise, low power dissipation, good linearity and high dynamic range. The single readout channel is built of an AC-coupling circuit with the cut-off frequency below 1 Hz, low noise preamplifier, two stages of band-pass filters with tuneable bandwidth from 1 Hz to 10 kHz and an output amplifier with variable gain. The circuit has been designed in a 0.35 mum CMOS process and it is suitable for integration in a multi-channel ASIC.
The paper concentrates on a speech recognition algorithm to work with speech samples of nonhomogeneous quality. The speech samples are acquired using different microphones and are of different quality. Two algorithms ...
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The paper concentrates on a speech recognition algorithm to work with speech samples of nonhomogeneous quality. The speech samples are acquired using different microphones and are of different quality. Two algorithms of feature extraction are utilized,including the use of Toeplitz matrices and distances of feature points from the Cartesian origin point (0;0) as a reference point. For classification the Nearest Neighbor approach is used. The obtained results are *** paper also involves the description of the process in the preparation of speech samples. The approach to estimate the frequency range which contains enough information for proper speech recognition is undertaken. The studies in this paper show that cutting frequencies above 2200 Hz have rather low influence on the proper recognition but may rather lead to increase the error rate.
The results of two different clusterization methods applied to six social networks are presented. It is shown that elements classified together by the differential equation method, are also classified to the one commu...
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The results of two different clusterization methods applied to six social networks are presented. It is shown that elements classified together by the differential equation method, are also classified to the one community by the Newman method. It is also shown that even though for all analysed networks the cumulative node degree distribution is described by the stretched-exponential law, the distribution of the nodes among different functional types is not the same for all networks.
Synthesis, X-ray analysis (300K) and Mössbauer effect studies in the intermetallic compounds (Y1-xGdx)(Fe0.7Co0.3)2 are reported. Cubic Laves phase MgCu2 – type, were observed across the series. Lattice paramete...
Synthesis, X-ray analysis (300K) and Mössbauer effect studies in the intermetallic compounds (Y1-xGdx)(Fe0.7Co0.3)2 are reported. Cubic Laves phase MgCu2 – type, were observed across the series. Lattice parameter is linearly increased with Gd concentration. The lattice parameters of the (Y1-xGdx)(Fe0.7Co0.3)2 series are compared to data previously observed for the R(Fe1−xCox)2 series (R= Y, Dy, Gd). 57Fe Mössbauer effect measurements for the series were realized at 4.2 and in the temperature range around the magnetic ordering temperature. Curie temperatures of the (Y1−xGdx)(Fe0.7Co0.3)2 series were determined using both electrical resistivity and Mössbauer effect measurements. The magnetic hyperfine field and Curie temperature increases with Gd content. The obtained magnetic hyperfine field and Curie temperatures for the series (Y1−xGdx)(Fe0.7Co0.3)2 are related to the data known for the R(Fe1−xCox)2 series (R= Y, Dy, Gd).
Basic physical properties of the compound TmCu2Ge2, crystallizing with the tetragonal ThCr2Si2-type crystal structure, were studied down to 350 mK. The temperature dependencies of the magnetic susceptibility, the spec...
Basic physical properties of the compound TmCu2Ge2, crystallizing with the tetragonal ThCr2Si2-type crystal structure, were studied down to 350 mK. The temperature dependencies of the magnetic susceptibility, the specific heat and the electrical resistivity exhibit distinct anomalies at TN = 3.8 K that can be associated with the onset of an antiferromagnetic ordered state. Above this temperature the reciprocal susceptibility obeys the Curie–Weiss law with the paramagnetic Curie temperature θp equal to 1.2 K and the effective magnetic moment μeff equal to 7.12 μB. In the same region, the electrical resistivity shows a metallic character. In the ordered state, another clear peak in the specific heat is observed at Tt = 1.7 K that likely manifests a change in the magnetic structure.
A test system developed for ABCN-25 for ATLAS Inner Detector Upgrade is presented. The system is based on commercial off the shelf DAQ components by National Instruments and foreseen to aid in chip characterization an...
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ISBN:
(纸本)9789290833352
A test system developed for ABCN-25 for ATLAS Inner Detector Upgrade is presented. The system is based on commercial off the shelf DAQ components by National Instruments and foreseen to aid in chip characterization and hybrid/module development complementing full custom VME based setups. The key differences from the point of software development are presented, together with guidelines for developing high performance LabVIEW code. Some real-world benchmarks will also be presented together with chip test results. The presented tests show good agreement of test results between the test setups used in different sites, as well as agreement with design specifications of the chip.
The (001) face of AIII-BV semiconductors presents a rich surface phase diagram, with several different stoichiometry-dependent reconstructions (surface phases)1. In particular, a c(8x2) reconstruction is observed for ...
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The (001) face of AIII-BV semiconductors presents a rich surface phase diagram, with several different stoichiometry-dependent reconstructions (surface phases)1. In particular, a c(8x2) reconstruction is observed for In(Ga)-rich InSb, InAs and GaAs. The most recent structural model of the reconstruction the so called ζ-model2, is based in the formation of subsurface AIII dimers. Recently, we have shown using scanning tunneling microscopy and frequency-modulated scanning atomic-force microscopy that, at cryogenic temperatures, these surfaces undergo reversible transitions to so far unknown exotic phases with multiple periods, partial disorder and fluctuations3.
We study electron transport through a semiconductor quantum ring with one input and two output terminals for an elastic scatterer present within one of the arms of the ring. We demonstrate that the scatterer not only ...
We study electron transport through a semiconductor quantum ring with one input and two output terminals for an elastic scatterer present within one of the arms of the ring. We demonstrate that the scatterer not only introduces asymmetry in the transfer probability to the two output leads but also reduces the visibility of the Aharonov-Bohm conductance oscillations. This reduction occurs in spite of the phase coherence of the elastic scattering and is due to interruption of the electron circulation around the ring by the potential defect. The results are in qualitative agreement with a recent experiment by Strambini et al. [Phys. Rev. B 79, 195443 (2009)]. We also indicate that the magnetic symmetry of the sum of conductance of both the output leads as obtained in the experiment can be understood as resulting from the invariance of backscattering to the input lead with respect to the magnetic field orientation.
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