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101.
102.
D. Kamińska A. Gajos E. Czerwiński D. Alfs T. Bednarski P. Białas C. Curceanu K. Dulski B. Głowacz N. Gupta-Sharma M. Gorgol B. C. Hiesmayr B. Jasińska G. Korcyl P. Kowalski W. Krzemień N. Krawczyk E. Kubicz M. Mohammed Sz. Niedźwiecki M. Pawlik-Niedźwiecka L. Raczyński Z. Rudy M. Silarski A. Wieczorek W. Wiślicki B. Zgardzińska M. Zieliński P. Moskal 《The European Physical Journal C - Particles and Fields》2016,76(8):445
103.
R. Kruszka M. Ekielski K. Gołaszewska K. Korwin-Mikke Z. Sidor M. Wzorek D. Pierścińska R. Sarzała T. Czyszanowski A. Piotrowska 《Opto-Electronics Review》2011,19(1):51-55
The results of modelling of the influence of photonic crystal on the performance of VCSEL-type semiconductor laser structure
are shown and indicate that the use of those structures would significantly improve the working parameters of the devices.
The method of fabrication of photonic crystals in the Bragg mirrors of GaAs/AlGaAs-based VCSELs is presented. 相似文献
104.
Michał Rachwalski Stanisław Leśniak Piotr Kiełbasiński 《Tetrahedron: Asymmetry》2010,21(21-22):2687-2689
Diastereomerically pure tridentate heteroorganic ligands containing hydroxyl, sulfinyl and aziridine moieties as nucleophilic centers, capable of binding to various organometallic reagents, have been proven to be highly efficient catalysts in the enantioselective addition of phenylethynylzinc to aldehydes to give the desired products in very high yields (up to 95%) and with ee’s up to 90%. The influence of the stereogenic centers located on the sulfinyl sulfur atom and in the aziridine moiety on the stereochemical course of the reaction is also discussed. 相似文献
105.
P. T. Jochym K. Parlinski A. M. Oleś 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,61(2):173-179
The magnetization distribution, its energetic characterization by the
interlayer coupling constants and lattice dynamics of (001)-oriented
Fe/Pt multilayers are investigated using density functional theory
combined with the direct method to determine phonon frequencies.
It is found that ferromagnetic order between consecutive Fe layers is
favoured, with the enhanced magnetic moments at the
interface. The bilinear and biquadratic coupling coefficients between Fe
layers are shown to saturate fast with increasing thickness of
nonmagnetic Pt layers which separate them. The phonon calculations
demonstrate a rather strong dependence of partial iron phonon
densities of states on the actual position of Fe monolayer
in the multilayer structure. 相似文献
106.
J. Gaca M. Wójcik A. Jasik K. Pierściński M. Kosmala A. Turos A. M. Abdul-Kaderd 《Opto-Electronics Review》2008,16(1):12-17
GaAs/AlAs Bragg mirrors on GaAs with varied number of layer pairs were grown, by molecular beam epitaxy (MBE), to be applied
for semiconductor saturable absorber mirrors (SESAMs) and intensity modulators. Due to the random variation of the growth
rate, substrate surface roughness, and interdiffusion at the interfaces, precise control of the growth conditions of deposited
layers poses a serious problem. Usually, thickness variations and composition grading at the heterointefaces result in variations
of the mirror reflectivity. In this paper, the high resolution X-ray diffraction (HRXRD), optical reflectance, Rutherford
backscattering/channelling (RBS), supported by numerical evaluation methods were employed to determine both the exact thickness
of each layer and the composition grading at the interface between succeeding layers of GaAs/AlAs-based mirrors. To reduce
ambiguity and to speed up the analysis, the rocking curves and RBS spectra were simulated concurrently, using results of one
simulation to verify the others. This process was carried out until the best fit between experimental and calculated curves
was achieved. The complementary use of both methods results in improved sensitivity and makes the whole process of evaluation
of the thickness variation of each layer and the size of the composition grading at the interfaces less time consuming. 相似文献
107.
J. Dubowik I. Gościańska Y. Kudryavtsev 《The European physical journal. Special topics》2008,158(1):113-118
We report on FMR experiments performed for the first time on thin Ni-Mn-Ga films clamped to the mica substrates and then fully
released from them. The aim is to evaluate the role of magnetoelastic coupling in stressed Ni-Mn-Ga Heusler alloy films that
undergo martensitic transformation. The experimental results show that the difference in the effective magnetization 4π(Meff tubes-Meff films) is negligible in the austenite phase and it increases to about 1–1.5 kG at temperatures well below the martensitic transformation.
The data suggests that magnetoelastic coupling in the martensite phase of Ni-Mn-Ga thin films is typical of normal thin magnetic
films with magnetostriction of about 50 ppm. 相似文献
108.
M. Choraś 《Opto-Electronics Review》2008,16(1):85-96
Geometrical methods of feature extraction from ear images in order to perform human identification are presented. Geometrical
approach is motivated by the actual procedures used by police and forensic experts (so-called ear otoscopy). In their work,
geometrical features of ears such as size, height, width, and shapes of earlobe are useful and valid proofs of identity. The
contribution of the article is development of the new and original methods of geometrical feature extraction from 2D ear images.
Four novel algorithms of ear feature extraction from contour images are described in detail. Moreover, identification results
obtained for each of the methods, based on the distance of feature vectors in the feature space, are presented. 相似文献
109.
Zofia Stepien/snm> 《Geometriae Dedicata》2002,93(1):37-45
We prove the formality property of any homogeneous space G/G
generated by an automorphism of finite order of a compact simple Lie group G. 相似文献
110.
Thermal analysis has been employed to measure changes of the heat capacity of ferromagnetic materials such as alloys in the region of the Curie temperature. Thermal response for these materials is usually small in this region. The necessary increase in sensitivity was achieved by applying temperature modulation. Results obtained by this technique including temperature-modulated differential thermal analysis simultaneously with A.C. thermomagnetometry are presented. 相似文献