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Приказ резултата 241-250 од 251
Preparation of nanostructured Zn-Cr-O spinel powders by ultrasonic spray pyrolysis
(Elsevier Sci Ltd, Oxford, 2001)
Ultrasonic spray pyrolysis (1.7 MHz) has been applied for the generation of zinc chromium oxide submicronic (470 nm) particles from the corresponding metal nitrate solution. Heterogeneous gas-liquid/solid chemical reactions ...
Component analysis of the fluorescence spectra of a lignin model compound
(Elsevier Science Sa, Lausanne, 2006)
In order to test whether lignin fluorescence originates from discrete fluorophores, fluorescence emission spectra of the lignin model dehydrogenative polymer (DHP) were analyzed by the band deconvolution method and ...
The influence of mechanical activation on the stoichiometry and defect structure of a sintered ZnO-Cr2O3 system
(Trans Tech Publications Ltd, 2004)
Mixtures of starting ZnO and Cr2O3 powders in equimolar quantities were mechanically activated by grinding using a high energy vibro-mill for 0, 40 and 80 minutes. Qualitative X-ray diffraction analysis made after sintering ...
Pyrosol preparation and structural characterization of SnO2 thin films
(Elsevier Science Sa, Lausanne, 2003)
Polycrystalline tin oxide thin films were prepared from ethanol solution Of SnCl2.H2O (concentrations: 0.05, 0.1, 0.2 and 0.4 mol/dm(3)) at different substrate temperatures ranging from 300 to 450 degreesC. The kinetic ...
The nature of structural changes in nanocrystalline ZnO powders under linear heating conditions
(Elsevier Sci Ltd, Oxford, 2004)
The nature of exothermal and irreversible structural changes observed during linear heating of nanocrystalline ZnO powders was investigated using differential scanning calorimetry, X ray, SEM and TEM analysis. Nanocrystalline ...
Microstructural characterization of mechanically activated ZnO-Cr2O3 system
(Elsevier Sci Ltd, Oxford, 2005)
An equimolar mixtures of starting ZnO and Cr2O3 powders were mechanically activated by grinding using a planetary ball mill for various periods of time (40-320min). Formation of nanocrystalline ZnCr2O4 as normal spine] ...
Evolution of the microstructure of disperse ZnO powders obtained by the freeze-drying method
(Elsevier Science Sa, Lausanne, 2004)
Freeze-drying, as a cryochemical powder processing method is applied in the synthesis of ZnO submicrometer to narrosized powders. The process involves rapid freezing of the sprayed precursor solution, drying under vacuum ...
Changes in activities of antioxidant enzymes during Chenopodium murale seed germination
(Acad Sciences Czech Republic, Inst Experimental Botany, Praha 6, 2008)
The activities and isoenzyme pattern of catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD) have been studied during germination of Chenopodium murale seeds. CAT and SOD activities were similar in dry seeds and ...
Influence of potential pulse conditions on the formation of honeycomb-like copper electrodes
(Elsevier Science Sa, Lausanne, 2009)
Electrodeposition of copper by pulsating overpotential (PO) regime in the hydrogen co-deposition range was examined by the determination of the average current efficiency of hydrogen evolution and by microscopic analysis ...
New insights into the structural organization of the plant polymer lignin
(New York Acad Sciences, New York, 2005)
The organizational features of lignin structure and the mechanism of its synthesis have significant implications for the response of the plant to stress. It was unknown whether the enzymic formation of lignin in the cell ...