AIRInternational audienc

The effect of electrochemical promotion of catalysis (EPOC or NEMCA effect) was investigated for the hydrogenation of CO2 using Ru catalyst electrodes supported on YSZ solid electrolyte pellets at temperatures 200–300 °C and ambient pressure. Methane was found to be the main reaction product at temperatures up to 240 °C, whereas CO dominated at higher temperatures. It was found that the O2– supply to the Ru surface causes a significant increase in the CH4 formation rate and selectivity, accompanied by a significant decrease in the rate of CO formation. This is a very rare case in which electrochemical promotion is found to promote a catalytic reaction and at the same time to poison a reaction proceeding in parallel with the promoted one. The faradic efficiency values were found to be on the order of 10–103, which are among the highest reported in the EPOC hydrogenation literature. The kinetic and electropromotion results can be interpreted, using the rules of electrochemical promotion, in terms of the changes in the surface RuO x /Ru ratio induced via potential application, as observed via ex situ XPS.

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We formulate a Bohr-type rotating particle model for three light particles of rest mass mo each, forming a bound rotational state under the influence of their gravitational attraction, in the same way that electrostatic attraction leads to the formation of a bound proton-electron state in the classical Bohr model of the H atom. By using special relativity, the equivalence principle and the de Broglie wavelength equation, we find that when each of the three rotating particles has the same rest mass as the rest mass of a neutrino or an antineutrino (∼ 0.05 eV /c 2 ) then surprisingly the composite rotating state has the rest mass of the stable baryons, i.e. of the proton and the neutron (∼ 1 GeV /c 2 ). This rest mass is due almost exclusively to the kinetic energy of the rotating particles. The results are found to be consistent with the theory of general relativity. The model contains no unknown parameters, describes both asymptotic freedom and confinement and also provides good agreement with QCD regarding the QCD condenstation temperature. Predictions for the thermodynamic and other physical properties of these bound rotational states are compared with experimental values.

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The kinetics and the electrochemical promotion of the hydrogenation of CO2 over Ru‐catalyst electrodes deposited on yttria‐stabilized zirconia (YSZ) and (Na+)‐β“‐Al2O3 solid electrolytes are investigated at temperatures between 200 and 340 °C and pressures up to 5 bar. In the case of both the O2− conductor (YSZ) and the Na+ conductor (β”‐Al2O3), the selectivity for CH4 production is enhanced significantly when using a positive potential by supplying of O2− to, or removal of Na+ from, the catalyst surface. The opposite effect is observed when using a negative applied potential, which suppresses CH4 formation and enhances the production of CO through the reverse water–gas shift reaction. However, at low Na coverage, and under reducing conditions, both methanation and H2 production are promoted by the application of a negative potential. The observed electrochemical promotion behavior in conjunction with the reaction kinetics is consistent with the rules of electrochemical and chemical promotion.

A Diesel Particulate Filter (DPF) regeneration process was investigated during aftertreatment exhaust of a simulated diesel engine under the influence of a Diesel Oxidation Catalyst (DOC). Aerosol mass spectrometry analysis showed that the presence of the DOC decreases the Organic Carbon (OC) fraction adsorbed to soot particles. The activation energy values determined for soot nanoparticles oxidation were 97 ± 5 and 101 ± 8 kJ mol(-1) with and without the DOC, respectively; suggesting that the DOC does not facilitate elementary carbon oxidation. The minimum temperature necessary for DPF regeneration was strongly affected by the presence of the DOC in the aftertreatment. The conversion of NO to NO(2) inside the DOC induced the DPF regeneration process at a lower temperature than O(2) (ΔT = 30 K). Also, it was verified that the OC fraction, which decreases in the presence of the DOC, plays an important role to ignite soot combustion.

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