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Application of mechanical activation in synthesizing multiferroic Pb(Fe1/2Nb1/2)O3 powders

Bochenek D., Dercz G., Oleszak D.

Archives of Metallurgy and Materials

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2011

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Vol. 56, iss. 4

1015-1015

EN

In the study, the method of high-energy powder milling - mechanical activation (MA) was used for synthesizing Pb(Fe1/2Nb1/2)O3 (PFN) powders. For the purpose of comparing the influence of high-energy milling on PFN synthesis, two groups of powder samples were used. The first mixture consisting of simple oxide powders; the second one consisting of compound oxide powders. The obtained powders were subjected to structural analysis with the use of XRD and Mőssbauer spectroscopy. Tests revealed that during the process of high-energy milling of initial constituents a partial synthesis of PFN material phases occurs. By comparing the two methods of PFN synthesizing it may be stated that mechanical activation in the case of a simple oxide mixture (PFN1) is equally effective as for a compound oxide mixture (PFN2).

PL

W pracy, w procesie technologicznym, wykorzystano metodę wysokoenergetycznego mielenia proszków – mechanicznej aktywacji (MA) do syntezowania proszków Pb(Fe1/2Nb1/2)O3 (PFN). Do porównania wpływu wysokoenergetycznego mielenia na synteze PFN wykorzystano dwie grupy próbek proszkowych. Pierwsza mieszanine stanowiły proszki prostych tlenków (jednoetapowa metoda otrzymywania – PFN1), druga stanowiły proszki złozonych tlenków (dwuetapowa metoda otrzymywania – PFN2). Otrzymane proszki poddano analizie strukturalnej przy użyciu XRD i spektroskopii Mossbauera. Badania potwierdziły, ze podczas procesu wysokoenergetycznego mielenia składników wyjsciowych zachodzi czesciowa synteza faz materiału PFN. Porównujac dwie metody syntetyzowania PFN można stwierdzić, że mechaniczna aktywacja jest jednakowo skuteczna w przypadku mieszaniny prostych tlenków (PFN1) jak i dla mieszaniny złożonych tlenków (PFN2).

2

The maximum entropy method in the analysis of the Mössbauer spectra

Dobrzyński L., Szymański K., Satuła D.

Nukleonika

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2004

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Vol. 49,suppl.3

89-93

EN

The paper shows the possibility of reconstruction of the distribution of hyperfine field parameters without prior assumptions concerning correlations between parameters. The method used is the maximum entropy method and the distributions considered concern the magnetic field and isomer shift. The results obtained are very encouraging and show the feasibility of the proposed method.

3

Nanocrystallization studies of rapidly quenched Fe85.4-xCoxZr6.8-yNbyB6.8Cu1 (x = 0 or 42.7, y = 0 or 1) alloys

Olszewski J., Zbroszczyk J., Ciurzyńska W., Fukunaga H., Wysłocki B., Perduta K., Łukiewska A., Młyńczyk A., Lelątko J., Świerczek J.

Nukleonika

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2003

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Vol. 48,suppl.1

49-52

EN

The microstructure of amorphous and nanocrystalline Fe42.7Co42.7Zr6.8-xNbxB6.8Cu1 (x = 0 or 1) alloys was investigated. We have stated that the nanocrystalline samples consist of the crystalline alfa-FeCo grains about 8 nm in diameter embedded in an amorphous matrix which is rich in cobalt. From Mössbauer spectroscopy studies we have found that the crystalline alfa-FeCo phase in the nanocrystalline samples obtained by the conventional annealing is atomically ordered. Moreover, the order degree depends on the annealing time. As for the samples partially crystallized during rapid quenching, the crystalline alfa-FeCo phase is atomically disordered.

4

Physico-chamical properties and X-ray study of trinuclear carboxylate [Fe3O(CH3COO)6(H2O)3]2[PtCl6] 8H2O

Turta C., Shova S., Meriacre V., Cadelnic I., Gdaniec M.

Polish Journal of Chemistry

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1999

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vol. 73 nr 4

607-618

EN

Trinuclear carboxylate compound [Fe3O(CH3COO)6(h2o)3]2[PtCl6]× 8H2O has been studied by Mossbauer spectroscopy, magnetochemistry, thermal analysis and X-ray crystallography. Crystal data: monoclinic, space group P21/n, a = 10.505(2), b = 14.278(3), c = 19.885(4) A, b=96.00(3)0 and Z = 2. The final R-value is 0.027 for 4606 reflections with I ł 2s(I). The crystal consists of the complex [Fe3O(CH3COO)6(H2O3]+ cations, centrosymmetric [PtCl6]2- anions and water molecules. The [Fe3O(CH3COO)6(H2O)3]+ cation has the typical structure of a trinuclear iron (III) compound with m3-O bridge. All crystal components are connected via a system of hydrogen bonds into a 3D network. Mossbauer spectrum displays at room temperature a single quadrupole doublet with an isomer shift of 0.70 mm/s and quadrupole splitting of 0.48 mm/s, consistent with high-spin Fe(III). mcff per Fe atom (3.25 mB at 293 K and 2.23 mB at 120 K), indicate the antiferromagnetic coupling between the paramagnetic iron with J = -31 cm -1.