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891.
892.
Li ZP Petracic O Morales R Olamit J Batlle X Liu K Schuller IK 《Physical review letters》2006,96(21):217205
Asymmetric magnetization reversal is an unusual phenomenon in antiferromagnet/ferromagnet (AF/FM) exchange biased bilayers. We investigated this phenomenon in a simple model system experimentally and by simulation assuming inhomogeneously distributed interfacial AF moments. The results suggest that the observed asymmetry originates from the intrinsic broken symmetry of the system, which results in local incomplete domain walls parallel to the interface in reversal to negative saturation of the FM. The magneto-optical Kerr effect unambiguously confirms such an asymmetric reversal and a depth-dependent FM domain wall in accord with the magnetometry and simulations. 相似文献
893.
In this paper, we analyze equilibria in competitive environments under constraints across players’ strategies. This means that the action taken by one player limits the possible choices of the other players. In this context, the usual approach to show existence of equilibrium, Kakutani’s fixed point theorem, cannot be applied directly. In particular, best replies against a given strategy profile may not be feasible. We devise a new fixed point correspondence to deal with the feasibility issue. 相似文献
894.
J.C. Arrebola A. Caballero J.L. Gómez-Cámer L. Hernán J. Morales L. Sánchez 《Electrochemistry communications》2009,11(5):1061-1064
An advanced high-voltage Li-ion battery is reported. The electrodes are prepared from a lithium–nickel–manganese spinel as cathode and silicon nanoparticles as anode. The specific capacity as referred to the anode material is 1700 mA h g?1, which is much higher than the reported values for most existing Li-ion batteries. 相似文献
895.
Alma R. Morales Dr. Katherine J. Schafer‐Hales Dr. Ciceron O. Yanez Mykhailo V. Bondar Dr. Olga V. Przhonska Dr. Adam I. Marcus Prof. Kevin D. Belfield Prof. 《Chemphyschem》2009,10(12):2073-2081
The steady‐state photophysical, NMR, and two‐photon absorption (2PA) properties of a new fluorene derivative ( 1 ) containing the 2‐(2′‐hydroxyphenyl)benzothiazole (HBT) terminal construct is investigated for use as a fluorescence probe in bioimaging. A comprehensive analysis of the linear spectral properties reveals inter‐ and intramolecular hydrogen bonding and excited state intramolecular proton transfer (ESIPT) processes in the HBT substituent. A specific electronic model with a double minimum potential energy surface is consistent with the observed spectral properties. The 2PA spectra are obtained using a standard two‐photon induced fluorescence method with a femtosecond kHz laser system, affording a maximum 2PA cross section of ~600 GM, a sufficiently high value for two‐photon fluorescence imaging. No dependence of two‐photon absorption efficiency on solvent properties and hydrogen bonding in the HBT substituent is observed. The potential use of this fluorenyl probe in bioimaging is demonstrated via one‐ and two‐photon fluorescence imaging of COS‐7 cells. 相似文献
896.
897.
Behshid Behdadfar Ahmad Kermanpur Hojjat Sadeghi-Aliabadi Maria del Puerto Morales Morteza Mozaffari 《Journal of magnetism and magnetic materials》2012
Superparamagnetic and monodispersed aqueous ferrofluids of Zn substituted magnetite nanoparticles (ZnxFe3−xO4, x=0, 0.25, 0.3, 0.37 and 0.4) were synthesized via hydrothermal-reduction route in the presence of citric acid, which is a facile, low energy and environmental friendly method. The synthesized nanoparticles were characterized by X ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, scanning and transmission electron microscopy (SEM and TEM) and the dynamic light scattering (DLS) method. The results showed that a certain amount of citric acid was required to obtain single phase Zn substituted magnetite nanoparticles. Citric acid acted as a modulator and reducing agent in the formation of spinel structure and controlled nanoparticle size and crystallinity. Mean particle sizes of the prepared nanoparticles were around 10 nm. The results that are obtained from XRD, magnetic and power loss measurements showed that the crystallinity, saturation magnetization (MS) and loss power of the synthesized ferrofluids were all influenced by the substitution of Zn in the structure of magnetite. The Zn substituted magnetite nanoparticles obtained by this route showed a good stability in aqueous medium (pH 7) and hydrodynamic sizes below 100 nm and polydispersity indexes below 0.2. The calculated intrinsic loss power (ILP) for the sample x=0.3 (e.g. 2.36 nH m2/kg) was comparable to ILP of commercial ferrofluids with similar hydrodynamic sizes. 相似文献
898.
N. Morales Mendoza S. Goyanes C. Chiliotte V. Bekeris G. Rubiolo R. Candal 《Physica B: Condensed Matter》2012,407(16):3203-3205
Magnetic binary nanofillers containing multiwall carbon nanotubes (MWCNT) and hercynite were synthesized by Chemical Vapor Deposition (CVD) on Fe/AlOOH prepared by the sol–gel method. The catalyst precursor was fired at 450 °C, ground and sifted through different meshes. Two powders were obtained with different particle sizes: sample A (50–75 μm) and sample B (smaller than 50 μm). These powders are composed of iron oxide particles widely dispersed in the non-crystalline matrix of aluminum oxide and they are not ferromagnetic. After reduction process the powders are composed of α-Fe nanoparticles inside hercynite matrix. These nanofillers are composed of hercynite containing α-Fe nanoparticles and MWCNT. The binary magnetic nanofillers were slightly ferromagnetic. The saturation magnetization of the nanofillers depended on the powder particle size. The nanofiller obtained from powder particles in the range 50–75 μm showed a saturation magnetization 36% higher than the one formed from powder particles smaller than 50 μm. The phenomenon is explained in terms of changes in the magnetic environment of the particles as consequence of the presence of MWCNT. 相似文献
899.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献