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51.
J.?DubowikEmail author F.?Stobiecki I.?Go?ciańska Y. P.?Lee A.?Paetzold K.?R?ll 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,45(2):283-288
The temperature dependencies of the ferromagnetic
resonance (FMR) linewidth and the resonance field-shift have been
investigated for NiO/NiFe exchange-biased bilayers from 78 K to 450 K. A broad maximum in the linewidth of 500 Oe, solely due to the
exchange-bias, is observed at ≈150 K when the magnetic
field is applied along the film plane. When the magnetic field is
applied perpendicular to the film plane, the maximum in the
linewidth is less pronounced and amounts to 100 Oe at the same
temperature. Such a behavior of the FMR linewidth is accompanied
with a monotonic increase in the negative resonance field-shift
with decreasing temperature. Our results are compared with the
previous experimental FMR and Brillouin light scattering data for
various ferromagnetic/antiferromagnetic (FM/AF) structures, and
suggest that spin dynamics (spin-wave damping and anomalous
resonance field-shift) in the FM/AF structures can be described in
a consistent way by a single mechanism of the so-called
slow-relaxation. 相似文献
52.
Majumder G Abe K Abe K Adachi I Aihara H Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM Banerjee S Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fratina S Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou S Hou WS 《Physical review letters》2005,95(4):041803
We report evidence for B(0) --> D(0)D(-) and the first observation of the decay modes B(-) --> D(0)D(-) and B(-) --> D(0)D(*-) based on a sample of 152 x 10(6) BB events collected by the Belle detector at KEKB. The branching fractions for B(0) --> D(+) D(-), B--->D(0)D(-), and B--> D(0)D(*-) are found to be (1.91 +/- 0.51 +/- 0.30) x10(-4), (4.83 +/- 0.78 +/- 0.58) x 10(-4), and (4.57 +/- 0.71 +/- 0.56) x 10(-4), respectively. Charge asymmetries in the B---> D(0)D(-) and B(-) --> D(0)D(*-) channels are consistent with zero. 相似文献
53.
We define a quotient of bounded operators and on a Hilbert space with a kernel condition as the mapping , . A quotient is said to be positive symmetric if . In this paper, we give a simple construction of positive selfadjoint extensions of a given positive symmetric quotient .
54.
Simultaneous confidence bands for the integrated hazard function 总被引:1,自引:1,他引:0
The construction of the simultaneous confidence bands for the integrated hazard function is considered. The Nelson–Aalen estimator
is used. The simultaneous confidence bands based on bootstrap methods are presented. Four methods of construction of such
confidence bands are proposed. The weird and conditional bootstrap methods are used for resampling. Simulations are made to
compare the actual coverage probability of the bootstrap and the asymptotic simultaneous confidence bands. It is shown that
the equal-tailed bootstrap confidence band has the coverage probability closest to the nominal one. We also present application
of our confidence bands to the data regarding survival after heart transplant.
This research was partly supported by AGH grant No. 10.420.03. 相似文献
55.
St. Gołab 《Mathematische Annalen》1939,116(1):768-780
Ohne Zusammenfassung 相似文献
56.
Voltammetric and microscopic data on the analytical properties of small iridium-based (127- μm diameter) mercury film electrodes are presented. A method of estimating and controlling the size of the deposit is described. The voltammetric behaviour of electrodes with mercury deposits varying from a film to a near-hemisphere is discussed for linear-scan, differential- and normal- pulse voltammetry. The systems Pb2+/Pb, Fe3+/Fe2+ and Co2+/Co, are used to show that, by changing the size of the deposit, either time-dependent or almost time-independent (steady-state) voltammograms can be obtained under the same instrumental conditions. Possible applications to the determination of high concentrations of depolarizers are outlined; voltammetric data for the determination of lead in the range 10–120 mM are presented. The evaluation of diffusion coefficients is discussed. 相似文献
57.
The aim of this work was to investigate the efficiency of various MWCNTs as SPE materials for the preconcentration of chlorophenols. The COOH-functionalized MWCNTs and MWCNTs were used as SPE sorbents. To evaluate the capability of MWCNTs for the preconcentration of chlorophenols from water samples, 2,4-chlorophenol, 4-chlorophenol, 2,4,6-chlorophenol, 2,6-chlorophenol, 3,4-chlorophenol, and 2-chlorophenol were used as model compounds. Chlorophenols were extracted with acetone, methanol, ethanol, and dichloromethane, and determined by gas chromatography–mass spectrometry. COOH-functionalized MWCNTs <8 nm were found to be the best sorbent for the tested chlorophenols. For COOH-functionalized MWCNTs <8 nm, the recovery rates for all chlorophenols were higher than 50% when acetone or ethanol was used as eluents. In the case of dichloromethane elution, recovery rates for chlorophenols were from 62.0% for 2,6-DCP to 116.8% for 2,4-DCP; only for 2,4,6-TCP was the recovery rate 30.6%. Similar percentage recoveries were achieved with methanol as the eluent. 相似文献
58.
Upon visible-light irradiation, reductive carboxylation of alkyl halides takes place by using a SmI2/Sm mixed system under atmospheric CO2 to afford the corresponding carboxylic acids in good to excellent yields. 相似文献
59.
60.
Noriaki Suetake Hideaki Kawano Go Tanaka Hidenobu Hashikami Eiji Uchino 《Optical Review》2011,18(6):423-429
In this paper, a new image enlargement method applying the backprojection for lost pixel (BPLP) to the predefined codebook-based
method is proposed. BPLP is a method for image restoration. In BPLP, the eigenspace reflecting the characteristics of an input
image is generated from the remained pixels and is used to restore the missing pixels. In the proposed method, the eigenspace
is replaced by one generated from the predefined codebook (PDC). PDC represents edge-blurring properties in a small image
patch and consists of pairs of low- and high-frequency image patches on various edge patterns. By replacing the PDC-based
estimation of lost high-frequency components with BPLP, a fast image enlargement method retaining its performance can be developed.
Through some experiments, the effectiveness of the proposed method was demonstrated. Especially, it was confirmed that the
processing time of the proposed method was shortened to about 1/50 that of the PDC-based method. 相似文献