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255.
František Lehar 《Czechoslovak Journal of Physics》1958,8(5):583-590
, ZnS(Ag) . ZnS(Ag) . Po-Be, Ra-Be Li(d, n), C(d, n), N(d, n), Be(d, n). -, Co60, Cs137
Ra, , -, Li(p, ). , . 相似文献
256.
František Březina 《Monatshefte für Chemie / Chemical Monthly》1966,97(1):281-286
Zusammenfassung Es wurde präparativ das System LaCl3–H3
M–KOH studiert. Die Verbindungen LaH3
M
2, La2H3
M
3·5 H2O, LaM·3 H2O und K5LaH4
M
4·H2O wurden isoliert und ihre Löslichkeit sowie Temperaturstabilität bestimmt; ferner wurden Debyeogramme und Infrarotspektren aufgenommen.
Mit 3 Abbildungen
9. Mitt.:F. Bezina, R. Pastorek undL. Halbertát, Acta Univ. Palack., im Druck; in der Reihe Koordinationsverbindungen von organischen Oxosubstanzen, 29. Mitt. 相似文献
The system LaCl3–H3 M–KOH (H3 M=C4H6O5) was studied, and the compounds LaH3 M 2, La2H3 M 3·5 H2O, LaM ·3 H2O and K5LaH4 M 4·H2O isolated. Their solubilities and stability towards temperature changes were determined, and the powder diagrams as well as the I. R. spectra recorded.
Mit 3 Abbildungen
9. Mitt.:F. Bezina, R. Pastorek undL. Halbertát, Acta Univ. Palack., im Druck; in der Reihe Koordinationsverbindungen von organischen Oxosubstanzen, 29. Mitt. 相似文献
257.
A novel In(3+)-doped TiO(2) and TiO(2)/In(2)S(3) nanocomposites for photocatalytic degradation of environmental pollutants and stoichiometric degradation of warfare agents were prepared by a homogeneous hydrolysis with urea and thioacetamide, respectively. The prepared samples series TiInTAA were annealed at 600°C. The prepared samples were characterized by X-ray powder diffraction, IR spectroscopy, Raman spectroscopy, specific surface area (BET) and porosity determination. The method of UV-Vis diffuse reflectance spectroscopy was employed to estimate band-gap energies. The photocatalytic activity (PCA) was tested by degradation of Orange dye, whereas stoichiometric activity was studied by degradation of sulfur mustard. Incorporation of In(3+) into titania lattice increases PCA of TiO(2) in the visible light and increases stoichiometric decomposition of sulfur mustard against nondoped TiO(2) as well. PCA of TiO(2)/In(2)S(3) composite depends on the optimal ratio of TiO(2):In(2)S(3) in composite, while the activity for stoichiometric decomposition of sulfur mustards depends on the content of In(2)S(3) in nanocomposite. 相似文献
258.
The methodology for separations of saccharides in standard electrophoretic systems has been transferred to the short-capillary electrophoresis format. The laboratory-designed apparatus used employs a quartz capillary with an internal diameter of 10 μm, a total length of 10 cm, and an effective length of 4 cm, in combination with contactless conductivity detection. It has been applied to separations of neutral mono- and disaccharides. The saccharides are separated in the anionic form, in solutions of alkali hydroxides, namely, KOH, NaOH, and LiOH. The separation of a model mixture of five saccharides (sucrose, lactose, glucose, fructose, and ribose) takes less than 1 min, the LOD equaling 15, 35, 19, 17, and 24 mg L(-1) and the LOQ equaling 52, 117, 63, 53, and 79 mg L(-1) for sucrose, lactose, glucose, fructose, and ribose, respectively. The technique developed has been used to determine sucrose, glucose and fructose in high-energy drinks. The separation is finished within less than 50 s; the saccharide contents determined are identical with the declared values within the reliability interval in most cases, the RSD value being mostly less than 2%. In general, the separation system developed is very convenient for rapid analyses of large sets of similar samples, e.g., in product quality control or environmental monitoring. 相似文献
259.
260.
Daniel Haško Jaroslav Bruncko František Uherek 《Applied Physics A: Materials Science & Processing》2014,117(3):1353-1358
Amorphous oxides-based devices are exposed, during fabrication, to different processing conditions affecting their properties. Zinc oxide is a prospective candidate for transparent amorphous oxides, but its structure is changing under the influence of temperature. We investigated surface recrystallization of amorphous zinc oxide layers deposited onto fused silica, sapphire and Si substrates by pulsed laser deposition. The prepared three series of layers had highly nonequilibrium phase structures. Using atomic force microscopy and scanning electron microscopy, the effect was studied of subsequent annealing at 200, 400, 600, 800 °C for 60 min upon the surface structural properties of the layers. The following parameters were analyzed: average roughness, RMS roughness and size of formed grains on selected places with 1 × 1 μm2 area. Surface structural analysis revealed that annealing led to recrystallization of the prepared layers and roughening of the structural features on the surface. With increasing annealing temperature, the calculated parameters were increasing. The average surface roughness of zinc oxide layers annealed at 800 °C is three times higher than that of the layers annealed at lower temperatures for all substrates used. The process dynamics of thermally caused recrystallization of the layers was different for each of the substrates used. 相似文献