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Mechanochemical synthesis of gamma-Bi2O3
(Elsevier, Amsterdam, 2004)
A series of gamma-Bi2O3 phases doped with Zn, Si, Pb and Fe was prepared by mechanochemical treatment of corresponding oxide mixtures with a nominal composition 6Bi(2)O(3) (.) MOx (MOx = ZnO, SiO2, PbO) and 12Bi(2)O(3) (.) ...
Senescence-related changes in the antioxidant status of ginkgo and birch leaves during autumn yellowing
(Wiley, Hoboken, 2004)
The antioxidant status of birch and ginkgo leaves during autumnal senescence was characterized by the activities of catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX) and superoxide dismutase (SOD). The contents ...
Changes in sterlet (Acipenser ruthenus L.) catch and length frequency distribution in the Serbian part of the Danube River during the twentieth century
(Polish Academy of Sciences, 2004)
Data from a sample of 262 sterlet (Acipenser ruthenus L.) specimens from the Serbian part of the Danube River were compared with data collected between 1948 and 1967. The recent sample was caught between September 2002 and ...
Mechanochemical synthesis of CaTiO3 from CaCO3-TiO2 mixture
(Trans Tech Publications Ltd, 2004)
The synthesis of calcium titanate, CaTiO3, was performed by mechanical activation and thermal treatment. Milling for up to 360 minutes in a planetary ball mill mechanically activated an equimolar mixture of CaCO3 and TiO2 ...
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 ...
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 ...
Nature of structural changes in LSM-YSZ nanocomposite material during thermal treatments
(Elsevier Science Sa, Lausanne, 2004)
Nanocomposite powders in the system (La1-xSx)(a)MnO3-YSZ((1-y)) [LSM-YSZ], as an attractive cathode material for high operating solid oxide fuel cell (SOFC), were obtained through ultrasonic spray pyrolysis (1.7 MHz) method. ...
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 ...