Zobrazeno 1 - 10
of 86
pro vyhledávání: '"Jürgen Küppers"'
Autor:
Stefan Wehner, Yevgen Burkov, Jürgen Küppers, Helmut R. Brand, Stefan Karpitschka, Dieter Schmeisser
Publikováno v:
Physica D: Nonlinear Phenomena. 239:746-751
We present experimental results on rare transitions between two states due to intrinsic noise between two states in a bistable surface reaction, namely the catalytic oxidation of CO on Pd(111) surfaces. The mean time scales involved are typically of
Publikováno v:
ChemInform. 46
Noise is an everywhere phenomenon. Its influence could be described theoretically quite easily, but is hard to measure in an experiment. Catalytic reactions on surfaces can be described by nonlinear reaction-diffusion equations. For one of such surfa
Publikováno v:
Chemical Physics Letters. 423:39-44
PEEM (photoelectron emission microscopy) was employed to study the influence of a noisy reactant gas flux composition on the spatio-temporal pattern development in the CO oxidation reaction on stepped Ir(9 7 7) surfaces. Anisotropic diffusion of CO p
Publikováno v:
Physica D: Nonlinear Phenomena. 205:15-24
Admission of a mixed CO (fraction Y) and oxygen (fraction 1 − Y ) reactant gas flux to Ir(1 1 1) surfaces at substrate temperatures between 420 and 560 K leads to CO2(Y,T) rates which can be very well described by reaction-diffusion differential eq
Publikováno v:
Surface Science. 570:218-226
Adsorption of thermal (2000 K) D (H) atoms on HOPG surfaces prior to and after bombardment with 500 eV Ar ions was studied with thermal desorption and vibrational spectroscopies. Ion bombardment of HOPG generates vacancy (VD, displaced surface C atom
Publikováno v:
Chemical Physics Letters. 395:171-176
Adsorption of H (D) atoms on natural graphite (NG) single crystal and highly oriented pyrolytic graphite (HOPG) surfaces was studied with low-energy electron diffraction (LEED) and scanning tunnelling microscopy (STM). No superstructure was observed
Publikováno v:
The Journal of Physical Chemistry B. 108:14452-14461
We study the consequences of multiplicative temperature noise (MTN) on the kinetics of the reaction CO + O2→ CO2 on an Ir(111) single-crystal surface. Without applied MTN, the CO2 kinetics exhibits...
Autor:
D. Kolovos-Vellianitis, Jürgen Küppers
Publikováno v:
Surface Science. 548:67-74
H and D were adsorbed on Ag(1 0 0) and Ag(1 1 1) surfaces and characterized by thermal desorption spectroscopy. On Ag(1 0 0) surfaces hydrogen desorption from surface sites at 150 K and subsurface sites around 110 K was observed. Similarly, desorptio
Publikováno v:
Carbon. 42:337-343
The interaction of thermal (2000 K) H and D atoms with glassy carbon (GC) surfaces was investigated in ultrahigh vacuum environment using thermal desorption and reaction kinetics mass spectroscopy. Virgin GC surfaces (not previously subjected to stat
Publikováno v:
Carbon. 42:609-617
Adsorption of thermal (2000 K) D atoms on (0 0 0 1) surfaces of various highly oriented pyrolytic graphite (HOPG) and natural graphite substrates was studied under ultra high vacuum (UHV) conditions with thermal desorption spectroscopy (TDS). D chemi