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1

Analiza skutków oddziaływania wodoru na metale i stopy

Pietkun-Greber I., Janka R. M.

Chemistry-Didactics-Ecology-Metrology

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2011

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R. 16, NR 1-2

75--78

PL

W pracy przedstawiono zarówno pozytywne, jak i negatywne skutki oddziaływania wodoru na właściwości użytkowe metali i stopów. Omówiono możliwości wykorzystania wodoru jako nośnika energii w ogniwach paliwowych oraz dokonano charakterystyki podstawowych typów ogniw paliwowych, a także możliwości ich zastosowania.

EN

The paper presents both positive and negative effects of hydrogen on the properties of metals and alloys utility. The possibility of using hydrogen as an energy carrier in fuel cells was discussed and the characterization was madę of basie types of fuel cells, and their applłcability.

2

Nanocomposite LaNi5/Mg2Ni- and ZrV2/Mg2Ni-type hydrides

Nowak M., Jurczyk M.

Inżynieria Materiałowa

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2010

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Vol. 31, nr 2

171-174

EN

In this work, nanostructured composite LaNi5/Mg2Ni and ZrV2/Mg2Ni materials have been synthesized using the mechanical alloying process. The composites have been investigated by XRD for their phase compositions, crystal structure, grain size and particle morphology. Hydrogen storage capacities of the new materials have been measured using a Sieverts apparatus. The results show, for example, that nanostructured composite 50% La(Ni, Mn, Al, Co)5/50% (Mg, Mn)2Ni and 25% (Zr, Ti)(V, Cr, Ni)2.4/ 75% (Mg, Mn)2Ni material releases 1.65 and 1.38 wt. % hydrogen at room temperature, respectively. This is higher than in the microcrystalline LaNi5 (1.49 wt. %) or ZrV2 (0 wt. %) alloys. Their excellent properties are a result of the combined engineering of many factors: alloy composition, surface properties, microstructure and grain size.

PL

W pracy wytworzono nanokompozyty LaNi5/Mg2Ni i ZrV2/Mg2Ni za pomocą procesu mechanicznej syntezy. Przeprowadzono badania XRD w celu określenia składu fazowego, struktury krystalicznej i wielkości ziarna. Wyznaczono pojemności wodoru metodą Sieverta. Przeprowadzone badania wykazały, że nanokrystaliczne kompozyty 50% La(Ni, Mn, Al, Co)5/ 50% (Mg, Mn)2Ni i 25% (Zr, Ti)(V, Cr, Ni)2,4/75% (Mg, Mn)2Ni desorbują w temperaturze pokojowej odpowiednio 1,65 and 1,38% masowych wodoru. Są to wartości wyższe w porównaniu ze stopami mikrokrystalicznymi, które wynoszą odpowiednio 1,49% masowych w przypadku stopu LaNi5 i 0% w przypadku stopu ZrV2. Właściwości otrzymanych nanokompozytów są efektem wpływu wielu czynników: składu, struktury, wielkości ziarna i właściwości powierzchni.

3

Perspektywy ogniw wodorkowych (Ni-MH)

Czerwiński A., Rogulski Z., Dłubak J., Gumkowska A., Karwowska M.

Przemysł Chemiczny

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2009

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T. 88, nr 6

642-648

4

Pressure Induced Phase Transitions and EOS Derived for Laves Phase Deuterides ErFe2Dx (x = 1.35, 1.9 and 3.4)

Sugiura H., Filipek S. M., Paul-Boncour V., Marchuk I.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 10

1959-1972

EN

The energy dispersive X-ray diffraction patterns of ErFe2Dx deuterides [where x = 1.35 (alfa1 phase), x = 1.9 (alfa2 phase) and x = 3.4 (beta phase)] have been measured under pressure up to 31 GPa. Compression curves and equation of state (EOS) parameters were determined us ing ex per i men tal data. ErFe2D1.35 and ErFe2D1.9 de com posed into phases with low (alfa1 ,, alfa 2 ,) and high (alfa1 ,, alfa 2 ,,) deuterium concentrations around 8 GPa. As the pressure was raised above 8 GPa, the D con cen tra tion in the alfa1 ,, alfa 2 , phases re mained close to about x = 0.2 whereas in the alfa1 " alfa 2 ,, phases it in creased from x = 2.1 to a max i mum of x = 4.6 at about 20 GPa. This was accompanied with a progres sive distortion of the alfa1 ,, alfa 2 ,, phases from a cubic to wards an orthorhombic structure. This decomposi tion process occurs with a large hysteresis effect between loading and unloading cycles. A similar decomposition into beta , and beta ,, phases seem ingly oc curs also for ErFe2D3.4 at 11 GPa being accompanied with a change of initial rhombohedral (R3m) symmetry to another one. The D content in this new beta" phase (x ~4.6) be comes close to that of orthorhombic ErFe2H5. These processes have character of spinodal decomposition and are related to a lowering of its critical temperature upon applied pressure.

5

Energetic Characteristics of Solid Composite Propellants and Ways for Energy Increasing

Lempert D. B., Nechiporenko G. N., Manelis G. B.

Central European Journal of Energetic Materials

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2006

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Vol. 3, nr 4

73-87

EN

Energetic characteristics of solid composite propellants of different type and application are described - metal-free compositions containing an oxidizer and a fuel-binder only; compositions containing additionally an energetic compound (Al, Be, Mg, B), metal hydrides (AlH3, BeH2, BxNyHz). A considerable attention is attracted to analysis of oxidizers (ammonium perchlorate, hydroxylammonium perchlorate, ammonium dinitramide etc) because oxidizer occupies the greatest mass fraction in propellant and mostly that is the oxidizer that determines energetic characteristics of the propellant. The main principles of the using of different kinds of binder are considered. It was shown that the competence to choose the binder to the given oxidizer can increase considerably the energetic characteristics even without creation of new compounds. Ways to optimize solid composite propellants destined for missile complexes of different mass characteristics are described. Different ways to further development of solid composite propellants are presented - optimization of formulations basing on accessible components; creation of new more effective binders, having additional functions of oxidizer or gasifying component etc. Ecological problems of solid composite propellants are also a topic of the paper. Ways to decrease ecological danger while solid composite propellants using are investigated.

6

Hydrogen chemisorption on palladium surface in a high electric field

Tomaszewska A., Stępień Z. M.

Optica Applicata

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2005

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Vol. 35, nr 3

375-383

EN

Interaction of hydrogen with palladium surface in the presence of high electric field leads to the formation of complexes, which have been recorded as PdHx + (x = 1, 2, 3, 4). In the present work, quantum chemical calculations with Becke's three parameter hybrid functional using the LYP correlation functional (B3LYP) for hydrogen interaction with both single palladium atom and four- or six-atom clusters (such us tetra- and octahedral voids) have been performed. The binding energies, ionization potentials and free-space dipole moments for PdHx (x = 1, 2, 3, 4) molecules have been determined and the "critical" field values, characteristic of palladium hydrides field dissociation have been determined. The model of hydrogen adsorption in the threefold hollow site on the surface together with a subsurface interstitial chemisorption has been discussed. It has been found that hydrogen is bound more strongly in the tetrahedral void than in the octahedral one.

7

57Fe Mössbauer effect studies of ErFe11Ti and ErFe11TiH compounds

Gaczyński P., Tereshina I., Rusakov V., Nikitin S., Drulis H.

Nukleonika

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2003

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Vol. 48,suppl.1

25-29

EN

Ferromagnetic compounds ErFe11TiHx (x = 0, 1) have been investigated by 57Fe Mössbauer spectroscopy in the temperature range 20–300 K. Mössbauer spectra were analyzed in terms of a model which takes into account the local environment of Fe atoms on three crystallographic sites (8f, 8j and 8i) and an influence of the random distribution of titanium on the 8i site. The 14 sextets with different intensities have been considered. The temperature dependencies of hyperfine interaction parameters and subspectra contributions were derived from experimental spectra. The hyperfine fields and the isomer shift increasing upon hydrogenation are discussed in terms of the hydrogen-induced Wigner-Seitz unit cell expansion and the s-electrons transfer from Fe atoms to the adjacent hydrogen atoms.