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841.
K.T.A.L. Burm 《等离子体物理论文集》2007,47(6):458-464
The discharge behaviour of an atmospheric dielectric barrier parallel plate discharge, used for surface treatment, is studied. Since an uniform plasma is preferable for surface treatment, filaments must be avoided in the discharge. The occurrence of filaments can be detected by measuring the current flowing through the discharge. Current and voltage measurements give an indication of the power consumption by the plasma. The power consumption of the plasma as function of the applied frequency is examined. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
842.
843.
We report X-ray absorption near edge structures (XANES) study of CeAl2 thin films of various thicknesses, 40-120 nm, at Al K- and Ce L3-edges. The threshold of the absorption features at the Al K-edge shifts to the higher photon energy side as film thickness decreases, implying a decreased in Al p-orbital charges. On the other hand, from Ce L3-edge spectra, we observed a decrease in the 5d4f occupancy as the surface-to-bulk ratio increases. The valence of Ce in these thin films, as revealed by the Ce L3-edge spectral results, is mainly trivalent. From a more detailed analysis we found a small amount of Ce4+ contribution, which increases with decreasing film thickness. Our results indicate that the surface-to-bulk ratio is the key factor which affects the electronic structure of CeAl2 thin films. The above observations also suggest that charge transfer from Al to Ce is associated with the decrease of the film thickness. 相似文献
844.
O. Životský K. Postava L. Kraus M. Foldyna J. Pištora 《Journal of magnetism and magnetic materials》2006
In this paper we investigate the surface magnetic properties of as-quenched (AQ) CoFeCrBSi ribbons prepared by planar flow casting method with using magneto-optic Kerr effect (MOKE). Measured hysteresis loops in longitudinal and transversal configurations enable us to obtain the information of ribbons surface magnetic properties. Moreover, we suggest new magneto-optic method, which is based on measurements of magneto-optical effects depending on DC current flowing through the ribbon. Experimental data of AQ ribbons are then compared with the model, which describes the influence of incidence angle on magneto-optical angles. 相似文献
845.
M. Wada Y. Ishida T. Nakamura Y. Kanai T. M. Kojima A. Takamine Y. Yamazaki K. Okada A. Yoshida T. Kubo I. Katayama S. Ohtani V. Varentsov H. Wollnik V. Lioubimov H. A. Schuessler 《Hyperfine Interactions》2006,173(1-3):153-163
A next-generation slow radioactive nuclear ion beam facility (SLOWRI) which provides slow, high-purity and small emittance ion beams of all elements is being build as one of the principal facilities at the RIKEN RI-beam factory (RIBF). High energy radioactive ion beams from the projectile fragment separator BigRIPS are thermalized in a large gas catcher cell. The thermalized ions in the gas cell are guided and extracted to a vacuum environment by a combination of dc electric fields and inhomogeneous rf fields (rf carpet ion guide). From there the slow ion beam is delivered via a mass separator and a switchyard to various devices: such as an ion trap, a collinear fast beam apparatus, and a multi-reflection time of flight mass spectrometer. In the R&D works at the present RIKEN facility, an overall efficiency of 5% for a 100A MeV 8Li ion beam from the present projectile fragment separator RIPS was achieved and the dependence of the efficiency on the ion beam intensity was investigated. Recently our first spectroscopy experiment at the prototype SLOWI was performed on Be isotopes. Energetic ions of 10Be and 7Be from the RIPS were trapped and laser cooled in a linear rf trap and the specific mass shifts of these isotopes were measured for the first time. 相似文献
846.
Langevin approach implemented in the inelastic cross-sections measured for the low-energy electrons colliding with metallic
clusters points out that statical form of the polarizability dominate at energies less than 1.25 eV. The dynamical form comes
into play at energies around 1.3 eV. The form of the polarizabilities indicates that polarizability of the metallic clusters
is energy-dependent. 相似文献
847.
Nanosize aluminum substituted nickel zinc ferrites were prepared through aerosol route and characterized using TEM, XRD, magnetic measurements and Mössbauer spectroscopy. The particle size of as obtained samples was found to be ∼10 nm which increases up to ∼85 nm upon annealing at 1200 °C. The unit cell parameter ‘a’ decreases linearly with concentration of aluminum due to the small ionic radius of aluminum. The saturation magnetization for all the samples after annealing at 1200 °C lies in the range 12.9–72.6 emu/g and decreases linearly with concentration of aluminum. Room temperature Mössbauer spectra of all as obtained samples of ferrite compositions exhibited a broad doublet suggesting super paramagnetic nature. This doublet is further resolved into two doublets and assigned to the surface region and internal region atoms of the particles. The samples annealed at 1200 °C show broad sextets, which were fitted with five sextets, indicating different local environment of both tetrahedrally and octahedrally coordinated Fe cation. 相似文献
848.
A generalized linear differential equation in a Banach space is studied. The construction of a phase space and solutions with the help of the spectral theory of linear operators, ergodic theorems, and degenerate semigroups of linear operators is carried out. 相似文献
849.
M. F. Bundule A. F. Mishnev V. K. Lusis D. Kh. Mutsenietse A. Z. Zandersons G. Ya. Dubur 《Chemistry of Heterocyclic Compounds》1991,27(9):995-998
The molecular crystal structure of 4-phenyl-3,5-diethoxycarbonyl-1,2,6-trimethyl-1,2-dihydropyridine has been investigated by x-ray structural analysis. The three-dimensional structural properties of the molecule have been compared against the large observed reactivity of the 3-ethoxycarbonyl group with respect to nucleophilic substitution reactions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1236–1239, September, 1991. 相似文献
850.
S. E. Bogushevich V. N. Makatun A. K. Potapovich I. I. Ugolev 《Journal of Applied Spectroscopy》1991,55(4):1016-1020
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 4, pp. 613–618, October, 1991. 相似文献