[en] The average content of deuterium in Pd-electrodes has been controlled by measurements of the relative electrical resistance, being standardized with measurements at equilibrium in gaseous deuterium. At ambient inert pressure and at high pressures of gaseous deuterium up 4.5 kbar at 298 K, the cathodic uptake of deuterium was determined. Simultaneously, at high pressures of deuterium, the electrochemical oxidation of deuterium extracted from Pd-anodes was followed. The electrochemical deuterium uptake at ambient and high pressures corresponds to excess deuterium pressures of about 80-150 bars. These results devaluate uniquely at high estimate of deuterium activity by Fleischmann's and Pons' paper. The probable reason of this limited activity of cathodic deuterium seems to be formation of bubbles at this electrode. (author). 16 refs, 9 figs

[en] The TM4-TM5 model of higher-order structure of rhodopsin (a structural and functional template for G protein-coupled receptors, GPCRs) in the membrane was used to investigate a complex between oligomeric rhodopsin (Rh) and its G protein (transducin, Gt). Comparison with currently available models of oligomeric organization of GPCRs was made, and is discussed with experimental data which revealed a flexible intradimeric Rh interface. We also characterized the membranous anchor domain of Gt in the complex Rh-Gt, which is critically important for the binding of transducin to Rh

No abstract available

[en] The effect of absorbed hydrogen on the ¹⁴⁵Nd NMR in Nd₁₅Fe₇₇B₈ has been investigated at helium temperatures. Hydrogen absorption is accompanied by a drop of NMR frequencies and changes in the quadrupole splitting. The drop of NMR frequencies is related to the lattice expansion. The influence of the hydrogen on the spin reorientation can be responsible for the changes in the quadrupole splitting. (orig.)

No abstract available

[en] Among three intermetallic compounds existing in Y-Mn system the YMn₂ and Y₆Mn₂₃ can easily form interstitial hydrides while for YMn₁₂ existence of hydride has never been reported. At moderate hydrogen pressure YMn₂ and Y₆Mn₂₃ transform into YMn₂H_4.5 and Y₆Mn₂₃H₂₅ respectively. At high hydrogen pressure the YMn₂ (C15 or C14 parent structure) forms a unique YMn₂H₆ (s.g. Fm3m) complex hydride of fluorite structure in which one Mn atom Mn(1) and Y randomly occupy the 8c sites while second manganese (Mn2) in position 4a forms complex anion with 6 hydrogen atoms located in positions 24e. Formation of YMn₂H₆ independently of the structure of parent phase (C14 or C15) as well as occupation of the same site (8c) by Y and Mn(1) atoms suggested that also Y₆Mn₂₃ and YMn₁₂ could transform into YMn₂H₆ - type hydride in which suitable number of Y atoms will be substituted by Mn(1) in the 8c positions. This assumption was confirmed by exposing R₆Mn₂₃ and RMn₁₂ to 1 GPa of hydrogen pressure at 100⁰C. Formation of (R_xMn_2-x)MnH₆ (where x = 18/29 or 3/13 for R₆Mn₂₃ and RMn₁₂ hydrides respectively) was confirmed by XRD. Hydrogen concentration in both R₆Mn₂₃ and RMn₁₂ based hydrides reached H/Me = 2 thus value two times higher than in R₆Mn₂₃H₂₅.

No abstract available

[en] New hydrides and deuterides of Laves cubic phases ZrFe₂ and ZrCo₂ were synthesized by high hydrogen (deuterium) pressure technique. For both Laves phases the symmetry of lattice does not change but a large expansion of lattice parameter (by 8% for ZrFe₂ and by 4.5% for ZrCo₂) occurs during hydrides (deuterides) formation. In contrast to the relatively stable hydride (if stored in an inert atmosphere) formed in ZrFe₂, the ZrCo₂H₂ decomposes easily at 25^oC. Large lattice expansion of ZrFe₂ during the deuteride formation changes only slightly its magnetic properties. (author)

[en] A hexagonal hydride of ZrCr₂H_x with a hydrogen concentration of x 5.75 was synthesized using high hydrogen pressure (5 kbar) at 100 deg. C for 72 h. The synthesized hydride is well characterized as regards structure and/or stability, as compared with cubic or hexagonal ZrCr₂ hydrides that are formed under conventional hydrogenation conditions

[en] The exposure of RMn₂ (C15 or C14 cubic Laves phase, where R = Y; Dy; Ho or Er) to high deuterium pressure leads to formation of novel, unique YMn₂D₆, DyMn₂D₆, HoMn₂D₆ and ErMn₂D₆ deuterides with cubic Fm-3m symmetry. In spite of different structures and molecular volumes of parent RMn₂ compounds, the molar volumes of RMn₂D₆ deuterides are almost identical. In this paper, we present results of studies on RMn₂Dx (where R = Y, Dy, Ho and Er) submitted to compression up to 30 GPa in diamond anvil cell (DAC) combined with energy dispersive X-ray diffraction. The EOS (equation of state) parameters of the above four RMn₂D₆ samples and YMn₂D_x, with x ≤ 4 are compared. The EOS parameters of YMn₂D₆ are very similar to those of other RMn₂D₆ but very different than those of interstitial deuterides YMn₂D_x (x ≤ 4). The phase transition or segregation was not detected in RMn₂D₆ up to 30 GPa