01986nas a2200229   4500008004100000022001400041245013900055210006900194260006100263300001000324490000800334520112700342653002001469653001401489653001301503653001901516653001701535653001201552100003201564700003001596856013001626       2007                        eng d  a1011-372X00aFabrication of an effusive molecular beam instrument for surface reaction kinetics - CO oxidation and NO reduction on Pd(111) surfaces0 aFabrication of an effusive molecular beam instrument for surface  a233 SPRING STREET, NEW YORK, NY 10013 USAbSPRINGERcNOV  a50-580 v1193 a<p>A simple molecular beam instrument (MBI) was fabricated for measuring the fundamental parameters in catalysis such as, sticking coefficient, transient and steady state kinetics and reaction mechanism of gas/vapor phase reactions on metal surfaces. Important aspects of MBI fabrication are given in detail. Nitric oxide (NO) decomposition and NO reduction with carbon monoxide (CO) on Pd(111) surfaces were studied. Interesting results were observed for the above reactions and they support the efficiency of the MBI to derive the fundamental parameters of adsorption and catalysis. Sustenance of CO oxidation at 400 K is dependent mostly on the absence of CO-poisoning; apparently, CO + O recombination is the rate determining step &lt;= 400 K. NO adsorption measurements on Pd(111) surface clearly indicating a typical precursor kinetics. Displacement of the chemisorbed CO by NO on Pd(111) surfaces was observed directly with NO + CO beams in the transient kinetics. It is also relatively easy to identify the rate-determining step directly from the MBI data and the same was demonstrated for the above reactions.</p>10acarbon monoxide10acatalysis10akinetics10amolecular beam10anitric oxide10aPd(111)1 aThirunavukkarasu, Kandasamy1 aGopinath, Chinnakonda, S.  uhttp://library.ncl.res.in/content/fabrication-effusive-molecular-beam-instrument-surface-reaction-kinetics-co-oxidation-and-002869nas a2200265   4500008004100000022001400041245014500055210006900200260007100269300001400340490000600354520191100360653001202271653002802283653001302311653001402324653001902338653001702357653001402374653002502388100001502413700001602428700003002444856012902474       2014                        eng d  a2155-543500aTowards a sustainable and near ambient DeNO(x) under lean burn conditions: a revisit to no reduction on virgin and modified pd(111) surfaces0 aTowards a sustainable and near ambient DeNOx under lean burn con  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUN  a1801-18110 v43 a<p>Catalytic conversion of NO in the presence of H-2 and O-2 has been studied on Pd(111) surfaces, by using a molecular beam instrument with mass spectrometry detection, as a function of temperature and reactants composition. N-2 and H2O are the major products observed, along with NH3 and N2O minor products under all conditions studied. Particular attention has been paid to the influence of O-2 addition toward NO dissociation. Although O-2-rich compositions were found to inhibit the deNO(x) activity of the Pd catalyst, some enhancement in NO reduction to N-2 was also observed up to a certain O-2 content. The reason for this behavior was determined to be the effective consumption of the H-2 in the mixture by the added O-2 and O atoms from NO dissociation. NO was proven to compete favorably against O-2 for the consumption of H-2, especially &lt;= 550 K, to produce N-2 and H2O. Compared with other elementary reaction steps, a slow decay observed with the 2H + 0 -&gt; H2O step under SS beam oscillation conditions demonstrates its contribution to the rate-limiting nature of the overall reaction. Pd(111) surfaces modified with O atoms in the subsurface (Md-Pd(111)) induces steady-state NO reduction at near-ambient temperatures (325 K) and opens up a possibility to achieve room temperature emission control. A 50% increase in the reaction rates was observed at the reaction maximum on Md-Pd(111), as compared with virgin surfaces. Oxygen adsorption is severely limited below 400 K, and effective NO + H-2 reaction occurs on Md-Pd(111) surfaces. Valence band photoemission with a UV light source (He I) under different oxygen pressures with APPES clearly identified the characteristics of the Md-Pd(111) surfaces and PdO. The electron-deficient or cationic nature of Md-Pd(111) surfaces enhances the NO dissociation and inhibits oxygen chemisorption &lt;= 400 K under lean-burn conditions.</p>10adeNO(x)10aheterogeneous catalysis10aHydrogen10alean burn10amolecular beam10anitric oxide10aPalladium10asurface modification1 aRoy, Kanak1 aJain, Ruchi1 aGopinath, Chinnakonda, S.  uhttp://library.ncl.res.in/content/towards-sustainable-and-near-ambient-denox-under-lean-burn-conditions-revisit-no-reduction