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According to the special Program of the National Academy of Sciences of Ukraine, creation of the new giant Ukrainian radio telescope (GURT) was started a few years ago on the UTR-2 radio telescope observatory. The main goal is to reach maximum band at the lowest frequencies (10-70 MHz), effective area (step-by-step up to 100,000 sq.m), and high interference immunity for resolving many astrophysical tasks when the sensitivity is less limited by the confusion effects. These tasks include stellar radio astronomy (the Sun, solar wind, flare stars, pulsars, transients) and planetary one (Jupiter, planetary lightnings, Earth ionosphere, the Moon, exoplanets). This array should be complementary to the LOFAR, E-LOFAR systems. The first stages of the GURT (6 x 25 cross-dipole active elements) and broad-band digital registration of the impulsive and sporadic events were tested in comparison with the existing largest decameter array UTR-2.

Chemisorption properties of thin films of Pd evaporated onto Nb recrystallized-foil surface have been studied by temperature-programmed desorption (TPD) and by measurement of the work function changes (WFC) at room temperature. TPD results indicate two states of CO adsorbed in dependence on the thickness of the palladium layer. The low temperature state (330 K) occurs at low Pd coverages (about one monolayer). Second state, occurring at slightly higher temperature (370 K), is attributed to bulk Pd. WFC data show negligible change of the work function after deposition of small amounts of Pd onto a clean Nb surface. With increasing amount of Pd, ∆ϕ rises and reaches a saturation value. Adsorption of CO onto Pd/Nb surface caused the work function increase at all coverages of Pd deposited.

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Thermally programmed desorption technique has been applied to the investigation of "virgin" and repeated adsorption of carbon monoxide on Pd/Nb and Pd/Nb2O5/Nb systems. The desorbed products of the CO interaction with these surfaces, CO and CO2, were monitored with a quadrupole mass spectrometer. On the basis of presented results some of the observed differences between the metal- and oxide-supported active metal (Pd) have been ascribed to the morphological rather than to chemical (electronic) effects in these systems. The different excess kinetic energy dissipation of Pd atoms colliding with metallic or oxidic surface is considered to influence the initial growth of the Pd layer, resulting afterwards in a different morphology of the final Pd layers.

Thin and thick palladium overlayers were deposited onto clean and oxidized niobium surfaces. Thermally programmed desorption of carbon monoxide, chemisorbed at room temperature on these layers has been investigated. Qualitatively similar results, i.e., weak interaction of CO with thin Pd overlayers and a stronger one with thick overlayers both for Pd/Nb and for Pd/NbOJNb systems have been obtained.

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