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961.
962.
Julio Penin Santos Fernando J.G. Landgraf Geraldo Caixeta Guimarães 《Journal of magnetism and magnetic materials》2006
The paper describes effect of texture on the anisotropy of magnetic properties and shows that an Epstein strip arrangement including strips cut in a direction 45° to the rolling direction gives property values that are closer to the average values than the traditional RD+TD arrangement. 相似文献
963.
Marcos F. de Campos Marília Emura Fernando J.G. Landgraf 《Journal of magnetism and magnetic materials》2006
Electrical steels, when submitted to operation, present continuous decrease of their magnetic properties, depending on the carbon content. This effect is attributed to the increase of the size of carbides, a process also known as coarsening or Ostwald Ripening. Loss separation can offer a better understanding of this phenomenon. Experimental results show that all effect of aging is inside the hysteresis loss component, with the excess losses unaffected. The carbon content in electrical steels should be less than 25 ppm to avoid magnetic aging. 相似文献
964.
M. Mahjour-Shafiei H.R. Amir-Ahmadi J.C.S. Bacelar R. Castelijns K. Ermisch E.D. van Garderen I. Gašparić M.N. Harakeh N. Kalantar-Nayestanaki M. Kiš H. Löhner O. Scholten 《Physics letters. [Part B]》2006
A series of nucleon–nucleon bremsstrahlung (NNγ) experiments at 190 MeV incident beam energy have been performed at KVI in order to gain more insight into the dynamics governing the bremsstrahlung reaction. After initial measurements wherein the bremsstrahlung process was studied far away from the elastic limit, a new study was used to probe the process nearer to the elastic limit by measuring at lower photon energies. Measured cross sections and analyzing powers are compared with the predictions of a microscopic model and those of two soft-photon models. The theoretical calculations overestimate the data by up to ≈30%, for some kinematics. 相似文献
965.
J.D. Dutson D. Litvinov M.R.J. Gibbs Y. Inaba H. Muraoka K. O’Grady 《Journal of magnetism and magnetic materials》2006
In this paper, we discuss two key aspects of magnetisation reversal in magnetic thin films with perpendicular anisotropy. Firstly, a study has been made of the additional field required to erase data written perpendicular to a thin film recording disk as the linear data density is increased. It has been found that an increase in data density from 40 to 360 kfci results in an increase of 1.25 kOe in the field required to erase the data. Secondly, the effect of varying the level of exchange coupling by co-sputtering CoCrPt samples with SiO2 has been studied using a characterisation technique that is independent of the self-demagnetising field. It has been found that the samples are fully exchange de-coupled when the film contains >9.8% SiO2 and the activation volume of reversal remains constant for higher levels of SiO2. 相似文献
966.
Ligia E. Zamora G. A. Perez Alcazar J. M. Greneche S. Suriñach 《Hyperfine Interactions》2006,168(1-3):1057-1063
Fe60Mn10Al20Nb10, (Fe60Mn10Al30)95Nb5 and (Fe60Mn10Al30)90Nb10 ball milled powdered alloys were investigated using X-ray diffraction, Mössbauer spectrometry, thermomagnetic (TGM) and magnetization measurements. We studied the influence of Nb content and of different milling times on the structural and magnetic properties. Two main features can be concluded: (1) the FeAlMn induces a BCC phase whatever the Nb content is, and (2) as both increasing Nb content and milling time give rise to an highly disordered state in conjunction with a decrease of the ferromagnetic behavior. 相似文献
967.
The energy level alignment between C60 and Al has been investigated by using ultraviolet photoelectron spectroscopy. To obtain the interfacial electronic structure between C60 and Al, C60 was deposited on a clean Al substrate in a stepwise manner. The valence-band spectra were measured immediately after each step of C60 deposition without breaking the vacuum. The measured onset of the highest occupied molecular orbital energy level was located at 1.59 eV from the Fermi level of Al. The vacuum level was shifted 0.68 eV toward lower binding energy with additional C60 layers. The observed vacuum level shift means that the interface dipole exists at the interface between C60 and Al. The barrier height of electron injection from Al to C60 is 0.11 eV, which is smaller value than that of hole injection. 相似文献
968.
P. Kappen P.S. Hale N. Brack W. Prissanaroon P.J. Pigram 《Applied Surface Science》2006,253(3):1473-1479
Micro-patterns (80 μm and 10 μm) of copper and semi-conducting polypyrrole on insulating fluorinated ethylene propylene substrates were characterized using synchrotron-based X-ray Photoemission Electron Microscopy (X-PEEM), Near Edge X-ray Absorption Fine Structure (NEXAFS), and Atomic Force Microscopy (AFM). Electronic states in the polypyrrole are verified using the NEXAFS data, and sample degradation upon irradiation is addressed. X-PEEM images show homogeneous distributions of the corresponding elements in the patterns. They do not exhibit dichroic effects and give information about the growth of copper and polypyrrole (i.e. nucleation of Cu, overgrowth of PPy, formation of PPy granules). AFM results are used to verify the topography of the patterns and support the findings on pattern growth. 相似文献
969.
J. Balogh D. Kaptás L. F. Kiss T. Kemény L. Bujdosó I. Vincze 《Hyperfine Interactions》2006,169(1-3):1343-1347
Magnetic multilayers of 57Fe with nominal thickness, T
nom, between 0.4 and 1.0 nm separated by 3.0 nm Al spacer layers were prepared by alternate deposition of the constituents in
high vacuum. The samples were investigated at 4.2 K in external magnetic field. A fraction of Fe atoms corresponding to about
0.3 nm equivalent Fe-thickness was found to mix into the Al spacer. The extremely strong magnetic anisotropy observed for
T
nom < 0.8 nm is attributed to Fe layers of approximately two atomic planes thick. The anisotropy decreases considerably after
the building up of the third Fe atomic layer starts at T
nom = 0.8 nm, but full saturation was not achieved even for T
nom = 1 nm and 3 T magnetic field applied perpendicularly to the sample plane. 相似文献
970.
We have initiated a search for a new type of nuclear matter, theη-mesic nucleus, using beams from the multi-GeV hadron facility, COSY at Juelich, Germany. A large acceptance scintillator detector, ENSTAR has been designed and built at BARC, Mumbai and fully assembled and tested at COSY. A test run for calibration and evaluation has been completed. In this contribution we present the design and technical details of the ENSTAR detector and how it will be used to detect protons and pions (the decay products ofη-mesic bound state). The detector is made of plastic scintillators arranged in three concentric cylindrical layers. The readout of the detectors is by means of optical fibres. The layers are used to generate ΔE –E spectra for particle identification and total energy information of stopped particles. The granularity of the detector allows for position (θ and ?ø determination making the event reconstruction kinematically complete 相似文献