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991.
M. Belmeguenai S. Mercone C. Adamo T. Chauveau L. Méchin P. Monod P. Moch D. G. Schlom 《Journal of nanoparticle research》2011,13(11):5669-5675
Nearly 50-nm thick La0.7Sr0.3MnO3 (LSMO) films were grown on Si substrates using molecular beam epitaxy on (001) Si substrates over-layered by a 20 nm thick
SrTiO3 (STO) or by a 20 nm thick CaTiO3 (CTO) film. In addition, a reference LSMO film was directly deposited on a (001) STO substrate by pulsed laser deposition.
For all the samples, X-ray diffraction revealed an excellent epitaxy of the LSMO film and small mosaicity around (001), with
in-plane [100] and [010] cubic axes. The LSMO/CTO films are in-plane compressed while the LSMO/STO ones are in-plane extended.
The temperature dependence of their static magnetic properties was studied using a SQUID, showing a Curie temperature overpassing
315 K for all the samples. Hysteresis loops performed at room temperature (294 K) with the help of a vibrating sample magnetometer
(VSM) are also discussed. At 294 K Micro-strip ferromagnetic resonance (MS-FMR) was used to investigate the dynamic magnetic
properties. It allows concluding to a strong anisotropy perpendicular to the films and to a weak fourfold in-plane anisotropy
with easy axes along the [110] and [1[`1]0 1\bar{1}0 ] directions. Their values strongly depend on the studied sample and are presumably related to the strains suffered by the
films. 相似文献
992.
993.
994.
M. Lepers V. Zehnlé J. C. Garreau 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,62(3):449-456
We discuss a model for quantum computing with initially mixed states. Although such a
computer is known to be less powerful than a quantum computer operating with pure
(entangled) states, it may efficiently solve some problems for which no efficient
classical algorithms are known. We suggest a new implementation of quantum computation
with initially mixed states in which an algorithm realization is achieved by means of
optimal basis independent transformations of qubits. 相似文献
995.
José F. Cariñena Javier de Lucas Manuel F. Rañada 《International Journal of Theoretical Physics》2011,50(7):2114-2124
A geometric approach is used to study the Abel first-order differential equation of the first kind. The approach is based
on the recently developed theory of quasi-Lie systems which allows us to characterise some particular examples of integrable
Abel equations. Second order Abel equations will be discussed and the inverse problem of the Lagrangian dynamics is analysed:
the existence of two alternative Lagrangian formulations is proved, both Lagrangians being of a non-natural class. The study
is carried out by means of the Darboux polynomials and Jacobi multipliers. 相似文献
996.
In this study, through the method of rapid controlled precipitation (RCP), the influence of temperature and dissolved CO2 on the scaling capacity of mineral water in the presence of copper and zinc ions was studied in laboratory experiments. The results indicated that with a rise in temperature or concentration of dissolved CO2, the scaling time of Salvetat water greatly decreased and the rate of precipitation considerably increased; therefore, the minimum dosage of copper or zinc ion for achieving total inhibition of scaling needed to be increased, which would provide better guidance for practical use of metal ions in inhibiting the scaling of drinking water. 相似文献
997.
J. M. Kumpula J. Saramäki K. Kaski J. Kertész 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,56(1):41-45
According to Fortunato and Barthélemy, modularity-based community detection
algorithms have a resolution threshold such that small communities in a large
network are invisible. Here we generalize their work and show that the q-state
Potts community detection method introduced by Reichardt and Bornholdt
also has a resolution threshold. The model contains a parameter by which this threshold can be tuned, but no a priori principle
is known to select the proper value.
Single global optimization criteria do not seem capable for detecting all
communities if their size distribution is broad. 相似文献
998.
Chrystelle Brignone Caroline Grygar Manon Marcu Gaëlle Perrin Frédéric Triebel 《Journal of immune based therapies and vaccines》2007,5(1):5-15
Background
LAG-3 (CD223) is a natural high affinity ligand for MHC class II. The soluble form (sLAG-3) induces maturation of monocyte-derived dendritic cells in vitro and is used as a potent Th1-like immune enhancer with many antigens in animal models. To extend this observation to human, a proof of concept study was conducted with a clinical-grade sLAG-3, termed IMP321, coinjected with alum-non-absorbed recombinant hepatitis B surface antigen. 相似文献999.
Cowan ML Anache-Ménier D Hildebrand WK Page JH van Tiggelen BA 《Physical review letters》2007,99(9):094301
Temporal fluctuations in the phase of waves transmitted through a dynamic, strongly scattering, mesoscopic sample are investigated using ultrasonic waves, and compared with theoretical predictions based on circular Gaussian statistics. The fundamental role of phase in diffusing acoustic wave spectroscopy is revealed, and phase statistics are also shown to provide a sensitive and accurate way to probe scatterer motions at both short and long time scales. 相似文献
1000.
We describe the use of tapered hollow-core photonic crystal fibres for delivery and compression of ultrashort optical pulses. We demonstrate delivery of transform-limited pulses with less than 100 fs pulse length and above 50 nJ energy through 8 m of fibre, in a single transverse mode. 相似文献