Articles you may be interested inChemical alteration of the native oxide layer on InP(111) by exposure to hyperthermal atomic hydrogen XPS techniques are used for a comparative study of ion induced effects in simple oxides (Zr02, Si0 2 , Ti0 2 ) and complex oxides (ZrSi0 4 , CaTiSi0 5 , La z Ti0 5 , PbTi0 3 ). We have found that reduction effects in simple and complex oxides differ. The interpretation of altered layer composition has been qualitatively considered in terms of the preferential loss of oxygen and reverse chemical reactions.

We calculated the kinetic energies of the H-atom in ice Ih between 5 and 269 K and in water in the range 293-673 K. To do so we used the literature optical vibration frequencies of ice and water of the different phases assuming the harmonic approximation and decoupling between the degrees of freedom of translation, rotation (libration), and internal vibrations. Apart for ice at 269 K, good agreement was obtained with published experimental values for both cases. Similar agreement with experiment was found for the case of water confined in 14 A diameter carbon nanotubes at 268 K. However, serious deviations from measured values were found in nanotube water in the range 5-230 K. Possible reasons for those deviations are discussed.

We study a physical system consisting of noninteracting quasiparticles in disordered superconductors that have neither time-reversal nor spin-rotation invariance. This system belongs to class D within the recent classification scheme of random matrix ensembles, and its phase diagram contains three different phases: metallic and two distinct localized phases with different quantized thermal Hall conductances. We find that critical exponents describing different transitions (insulator-to-insulator and insulator-to-metal) are identical within the error of numerical calculations and also find that critical disorder of the insulator-to-metal transition is energy-independent.

We study in detail a critical line on the phase diagram of the Cho-Fisher network model separating three different phases: metallic and two distinct localized phases with different quantized thermal Hall conductances. This system describes non-interacting quasiparticles in disordered superconductors that have neither time-reversal nor spin-rotational invariance. We find that in addition to a tricritical fixed point $W_T$ on that critical line there exist an additional repulsive fixed point $W_N$ (where the vortex disorder concentration $W_N

Direct measurements of the kinetic energies of He atoms adsorbed on active carbon fibre (ACF), at submonolayer coverage, are reported. The electronvolt spectrometer (eVs) of the ISIS neutron source, that utilizes the neutron Compton scattering technique, was employed. The specific adsorption area of the ACF was 3000 m 2 g −1 . The momentum distribution of adsorbed helium was measured at 4.6 K and 10.2 K and the average kinetic energy K s was found: 54.3±3.0 K. This value is 30% higher than that estimated by assuming slit-shaped pores of dimensions ∼0.7 nm together with a nearly monolayer coverage on a graphitic type adsorber.