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861.
T. Butz Ch. Meinecke M. Morawski T. Reinert M. Schwertner D. Spemann J. Vogt 《Applied Surface Science》2005,252(1):43-48
This contribution deals with the morphological and elemental characterisation with high-energy (MeV) focused ion beams (in particular protons) with special emphasis on high spatial resolution in the sub-micrometer regime and very low minimum detection limits (sub-ppm) in trace element analysis. The most important methods like particle induced X-ray emission (PIXE), Rutherford backscattering spectrometry (RBS), as well as scanning transmission ion microscopy (STIM) and STIM-tomography will be illustrated by examples from material and life sciences. 相似文献
862.
The macroscopic approach for two-particle transfer reactions is applied in normal spherical nuclei and pairing deformation parameters βp are estimated. For Ni isotopes the macroscopic approach works reasonably well while for the lead region strong energy dependence of theβ p values has been observed. It is shown that alpha-transfer reactions can also be treated within this formalism as couplings of the two-neutron and two-proton channels. 相似文献
863.
864.
V. F. Tret’yakov A. G. Zakirova V. A. Matyshak T. N. Burdeinaya V. N. Korchak L. S. Glebov V. V. Lunin 《Kinetics and Catalysis》2006,47(6):873-880
According to X-ray diffraction analysis data, the test catalyst was a Ni-Cr spinel with an impurity of NiO. With the use of in situ IR spectroscopy, it was found that nitrite, nitrate, and acetate surface complexes occurred under the reaction conditions of the selective catalytic reduction of nitrogen oxides by propane in the presence of oxygen on the nickel-chromium catalyst. As the temperature was increased, the nitrite complexes were converted into nitrate species. The molar absorption coefficient of surface nitrate complexes was determined. According to IR-spectroscopic and TPD data, the nitrate complexes were bound relatively weakly to the surface. The temperature region of their existence was 50–200°C. The temperature region of existence of the surface acetate complexes was 200–400°C. The individual adsorption of oxygen was not observed; however, oxygen-containing surface sites (Cr5+=O) participated in the formation of the surface complexes of reactants. 相似文献
865.
866.
C.T. Hsieh 《Applied Surface Science》2005,252(5):1899-1909
A magnetic force microscopy is used to examine the domain walls in nickel and cobalt films deposited by argon ion sputtering. Thin nickel films deposited at high substrate temperatures exhibit coexistent Bloch and Neel walls. Films grown at room temperature display alternative Bloch lines with cap switches. These films agglomerate to form grains after annealed at high temperatures. The film composed of larger grains behaves better nucleation implying magnetic domains of closure, while the film composed of smaller grains exhibits more defects implying alternative Bloch lines. We have also observed domain displacements and cap switches, which occur due to precipitation of particles in small grain size films. Stripe domains are observed for film thicknesses larger than 100 nm. They become zigzag cells when an external field of 1.5 T is applied perpendicular to the surface of the films. This experiment indicates that the domain sizes in thin films and the strip widths for thick films both depend on the square-root of the film thickness, which varies from 5 to 45 nm and from 100 to 450 nm, respectively. 相似文献
867.
V. I. Voronkova I. N. Leont’eva N. I. Sorokina T. I. Ovsetsina I. A. Verin 《Crystallography Reports》2006,51(6):977-981
A series of iron-doped KTiOPO4 (KTP: Fe) single crystals in which iron substitutes for 0.1–0.3% titanium was grown. The structure of the KTP: Fe crystals was determined, and their dielectric and conducting properties were studied. An X-ray diffraction analysis failed to reveal such asmall amount of Fe+3 ions in titanium octahedral positions of the structure. It was found that an increase in the iron concentration results in a lowering of the symmetry of Ti(1)O6 and Ti(2)O6 octahedra. The splitting of the dielectric anomaly due to the ferroelectric phase transition was explained by the mechanism of incorporation of an impurity into different growth pyramids of the crystals. It was established that the aging of the KTP: Fe crystals leads to changes in the permittivity and electrical conductivity during long storage. 相似文献
868.
S.T. Mileiko V.M. Kiiko K.A. Khvostunkov 《Theoretical and Applied Fracture Mechanics》2006,45(1):41-45
A micromechanical model of island-type fibre/matrix interface is described and experimental data are represented and analysed. Changes in the interface strength during a cycle loadings and, correspondingly, changes in the creep resistance of a composite due the island-like scheme of the fibre/matrix interface are described. 相似文献
869.
T. Janssen 《Zeitschrift für Physik B Condensed Matter》1992,86(2):277-283
A discussion is given of the relation between different models for systems with incommensurate phases. Moreover, a generalisation of such models is introduced, which shows an alternative explanation for similar phase diagrams. To get this one may vary the range of the interactions and the numbers of degrees of freedom per site.Another generalization involves coupling to elastic degrees of freedom. Such a coupling may change the type of the incommensurate phase transition. 相似文献
870.
C Sanchez-Brunete T Salto J M Garcia-Baudin J L Tadeo 《Journal of chromatography. A》1991,562(1-2):525-530
Triallate residues in barley seedlings and soil samples were determined by gas chromatography with ion-trap detection. Soil was extracted with methanol on a mechanical shaker, and plants were extracted with acetonitrile in a Sorvall homogenizer. After evaporation of the organic solvents, the residue was dissolved in hexane, and plants extracts were cleaned-up on an alumina column. Gas chromatographic analysis was carried out using a BP-1 fused-silica capillary column with helium as carrier gas. To quantitate residues the total-ion chromatogram was obtained and then the selected-ion monitoring chromatograms were displayed at m/z 86 for triallate and at m/z 154 for the internal standard, methyl-(4-amino-2-chloro)-benzoate. The average recovery through the method from barley and soil samples was always higher than 80%. The limit of detection in the selected-ion mode was 0.01 mg/kg. Barley and soil samples treated with triallate were also analysed. A good agreement was observed between results obtained by this method and by gas chromatography with nitrogen-phosphorus detection. 相似文献