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排序方式: 共有141条查询结果,搜索用时 15 毫秒
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2.
Y. J. Wang C. M. Leung S. W. Or X. Y. Zhao H. S. Luo X. K. Lv Z. D. Zhang 《Applied Physics A: Materials Science & Processing》2009,97(1):201-204
We report an extrinsic magnetoelectric effect in composite laminates made by sandwiching one thickness-polarized 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 (PMN–PT) piezoelectric single crystal plate between two length-magnetized, polymer-based pseudo-1–3 (Tb0.3Dy0.7)0.5Pr0.5Fe1.55 magnetostrictive composite plates. The laminates exhibit large magnetoelectric voltage coefficients (α
V
) of ∼0.17 V/Oe with a flat response for frequencies in excess of 40 kHz and of ∼2.97 V/Oe at the natural resonance frequency
of ∼65 kHz. The distinct advantages of the laminates include high magnetic field sensitivity, low Joule heating loss, wide
operating bandwidth, and low cost. 相似文献
3.
Stock indexes for some European emerging markets are analyzed using an investment-horizon approach. Austrian ATX index and Dow Jones have been studied and compared with several emerging European markets. The optimal investment horizons are plotted as a function of an absolute return value. Gain–loss asymmetry, originally found for American DJIA index, is observed for all analyzed data. It is shown, that this asymmetry has different character for emerging and for established markets. For established markets, gain curve lies typically above loss curve, whereas in the case of emerging markets the situation is just the opposite. We propose a measure quantifying the gain–loss asymmetry that clearly exhibits a difference between emerging and established markets. 相似文献
4.
The relativistic mean-field models tested in previous works against nuclear matter experimental values,critical parameters and macroscopic stellar properties are revisited and used in the evaluation of the symmetry energyγ parameter obtained in three different ways. We have checked that, independent of the choice made to calculate theγ values, a trend of linear correlation is observed between γ and the symmetry energy(S_0) and a more clear linear relationship is established between γ and the slope of the symmetry energy(L_0). These results directly contribute to the arising of other linear correlations between γ and the neutron star radii of R_(1.0) and R_(1.4), in agreement with recent findings. Finally, we have found that short-range correlations induce two specific parametrizations, namely,IU-FSU and DD-MEδ, simultaneously compatible with the neutron star mass constraint of 1.93≤M_(max)/M_☉≤2.05 and with the overlap band for the L_0 ×S_0 region, to present γ in the range of γ=0.25±0.05. 相似文献
5.
I. Orúe P. Gorría F. Plazaola M. L. Fernández-Gubieda J. M. Barandiarán 《Hyperfine Interactions》1994,94(1):2199-2205
Mössbauer measurements have been performed on amorphous and nanocrystalline alloy ribbons of nominal composition Fe86Zr7Cu1B6. The nanocrystalline samples were obtained by annealing the as-quenched alloy at different temperatures in the range between 650 and 870 K. Mössbauer spectra of the as-quenched amorphous sample have been recorded at 77 K, room temperature and above the Curie temperature (330 K) at 360 K. We have also performed Mössbauer measurements at room temperature in the nanocrystalline alloys to characterize the phases that appear after the annealing and their relative concentration. The as-quenched sample spectra reveal the existence of two inequivalent sites for Fe. Such a feature is also observed in the remaining amorphous phase of the annealed samples. In the first steps of crystallization, -Fe precipitates and its concentration increases with the annealing temperature. The experimental results suggest that the composition of the whole amorphous phase does not suffer large changes during crystallization. 相似文献
6.
Román?OrúsEmail author 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(11):280
This is a short review on selected theory developments on tensor network (TN) states for strongly correlated systems. Specifically, we briefly review the effect of symmetries in TN states, fermionic TNs, the calculation of entanglement Hamiltonians from projected entangled pair states (PEPS), and the relation between the multi-scale entanglement renormalization ansatz (MERA) and the AdS/CFT or gauge/gravity duality. We stress the role played by entanglement in the emergence of several physical properties and objects through the TN language. Some recent results along these lines are also discussed. 相似文献
7.
Nonlinear Dynamics - The wheeled three-link snake model is a well-known example of an underactuated robotic system whose motion can be kinematically controlled by periodic changes of its internal... 相似文献
8.
D. A. H. Ament J. J. Nuño-Ballesteros B. Oréfice-Okamoto J. N. Tomazella 《Bulletin of the Brazilian Mathematical Society》2016,47(3):955-970
Given an analytic function germ f: (X, 0) → C on an isolated determinantal singularity or on a reduced curve, we present formulas relating the local Euler obstruction of f to the vanishing Euler characteristic of the fiber X ∩ f-1(0) and to the Milnor number of f. Restricting ourselves to the case where X is a complete intersection, we obtain an easy way to calculate the local Euler obstruction of f as the difference between the dimension of two algebras. 相似文献
9.
Or Dishi Yuval Rahav Dr. Raanan Carmieli Prof. Ori Gidron 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(62):e202202082
Macrocyclic furans are predicted to switch between global aromaticity and antiaromaticity, depending on their oxidation states. However, the macrocyclic furans reported to date are stabilized by electron withdrawing groups, which result in inaccessible oxidation states. To circumvent this problem, a post-macrocyclization approach was applied to introduce methylene-substituted macrocyclic furans, which display an extremely low oxidation potential of −0.23 vs. Fc/Fc+, and are partially oxidized in ambient conditions. Additional oxidation to the dication results in aromaticity switching to a global 30πe− aromatic state, as indicated by the formation of a strong diatropic current observed in the 1H NMR spectrum. NICS and ACID calculations support this trend and provide evidence for a different pathway for the global current in the neutral and dicationic states. According to these findings, macrocyclic furans can be rendered as promising p-type materials with stable oxidation states. 相似文献
10.
Qiu-Cheng Chen Zi-Ye Xiao Shachar Fite Dr. Amir Mizrahi Dr. Natalia Fridman Xuan Zhan Or Keisar Dr. Yair Cohen Prof. Dr. Zeev Gross 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11383-11388
Although the affinity of metallocorroles to axial ligands is quite low, this is not the case when the chelated element is phosphorus. This work is hence focused on the mechanism of ligand exchange of six-coordinate phosphorus corroles as a tool for affecting their chemical and physical properties. These fundamental investigations allowed for the development of facile methodologies for the synthesis of a large series of complexes and the establishment of several new structure/activity profiles that may be used to understand and predict spectroscopic features and for tailor-made modification of photophysical and electrochemical properties. This is exemplified by the facile access to complexes with terminal groups that are of large potential for practical applications based on click chemistry, optical imaging, and surface science. 相似文献