Interaction of carbon monoxide with atomic oxygen, atomic nitrogen, and nitric oxide on ruthenium (001): evidence for bridge-adsorbed carbon monoxide, site changes, and formation of isocyanate species

1991 ◽  
Vol 95 (20) ◽  
pp. 7785-7791 ◽  
Author(s):  
K. L. Kostov ◽  
P. Jakob ◽  
H. Rauscher ◽  
D. Menzel
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Atomic Oxygen ◽  
Atomic Nitrogen ◽  
Adsorbed Carbon

Reaction of atomic oxygen with adsorbed carbon monoxide on a platinum surface

1996 ◽  
Vol 104 (2) ◽  
pp. 742-757 ◽  
Author(s):  
J. Ree ◽  
Y. H. Kim ◽  
H. K. Shin
Keyword(s):  
Carbon Monoxide ◽  
Atomic Oxygen ◽  
Platinum Surface ◽  
Adsorbed Carbon

ATOMIC REACTIONS IN THE UPPER ATMOSPHERE

1960 ◽  
Vol 38 (10) ◽  
pp. 1688-1692 ◽  
Author(s):  
Joseph Kaplan ◽  
William J. Schade ◽  
Charles A. Barth ◽  
Alvin F. Hildebrandt
Keyword(s):  
Nitric Oxide ◽  
Oxygen Atom ◽  
Chemical Reactions ◽  
Digital Computer ◽  
Atomic Oxygen ◽  
Flow System ◽  
Reaction Rates ◽  
Upper Atmosphere ◽  
Atomic Nitrogen ◽  
Excitation Mechanism

The reaction rates of nine upper atmosphere chemical reactions have been analyzed with a digital computer. The dependence of the loss rates of atomic nitrogen and atomic oxygen as well as the relative concentrations of nitric oxide and nitrogen dioxide in the upper atmosphere are given. Using a flow system, nitrogen atoms were produced and then titrated by the addition of NO. The resulting nitrogen and oxygen atom densities were measured with an e.p.r. spectrometer. The dependence of the intensities of the nitrogen afterglow and the NO afterglow were related to the atom densities. An excitation mechanism for OI 5577 has been determined from the relation of the intensity of λ 5577 to the atom densities.

scholarly journals Continuous spectra inflames: the role of atomic oxygen in combustion

1944 ◽  
Vol 183 (992) ◽  
pp. 111-124 ◽  
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Atomic Oxygen ◽  
Green Emission ◽  
Combustion Mechanism ◽  
Oxides Of Nitrogen ◽  
High Concentration ◽  
Hydrocarbon Flames ◽  
Hydrogen Flame

The causes and types of continuous spectra emitted by flames are discussed and their importance stressed. It is shown that the yellow-green continuous spectrum emitted by some flames containing oxides of nitrogen is probably identical with the spectrum of the air after glow and is therefore due to a reaction between nitric oxide and atomic oxygen. It thus becomes possible to test for the presence of atomic oxygen in a flame by admitting nitric oxide and observing if a yellow-green emission results. For the carbon monoxide flame there appears to be a high concentration of atomic oxygen, both for the dry and moist flame. The combustion mechanism is discussed in detail using this knowledge. For the hydrogen flame a little atomic oxygen is present, but results do not permit of definite conclusions. For hydrocarbon flames there is no sign of atomic oxygen in the inner cone, and this is taken as strong evidence in favour of a peroxidation rather than a bydroxylation mechanism .

Ultra-Low Amounts of Palladium (0.005-0.05 Wt% Pd) Supported on Titania: Remarkable Low-Temperature Activity for NO Reduction with CO and Structure-Function Property Relationships in Methane Oxidation

2020 ◽  
Author(s):  
Konstantin Khivantsev ◽  
Libor Kovarik ◽  
Nicholas R. Jaegers ◽  
János Szanyi ◽  
Yong Wang
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Methane Oxidation ◽  
Steam Reforming ◽  
Methane Steam Reforming ◽  
Oxide Reduction ◽  
Water Steam ◽  
Methane Steam ◽  
Anatase Titania ◽  
Nitric Oxide Reduction

<p>Atomically dispersed Pd +2 cations with ultra-dilute loading of palladium (0.005-0.05 wt%) were anchored on anatase titania and characterized with FTIR, microscopy and catalytic tests. CO infrared adsorption produces a sharp, narrow mono-carbonyl Pd(II)-CO band at ~2,130 cm<sup>-1</sup> indicating formation of highly uniform and stable Pd+2 ions on anatase titania. The 0.05 wt% Pd/TiO<sub>2</sub> sample was evaluated for methane combustion under dry and wet (industrially relevant) conditions in the presence and absence of carbon monoxide. Notably, we find the isolated palladium atoms respond dynamically upon oxygen concentration modulation (switching-on and switching off). When oxygen is removed from the wet methane stream, palladium ions are reduced to metallic state by methane and catalyze methane steam reforming instead of complete methane oxidation. Re-admission of oxygen restores Pd<sup>+2</sup> cations and switches off methane steam reforming activity. Moreover, 0.05 wt% Pd/TiO<sub>2</sub> is a competent CO oxidation catalyst in the presence of water steam with 90% CO conversion and TOF ~ 4,000 hr<sup>-1</sup> at 260 ⁰C. </p><p>More importantly, we find that diluting 0.05 wt% Pd/titania sample with titania to ultra-low 0.005 wt% palladium loading produces a remarkably active material for nitric oxide reduction with carbon monoxide under industrially relevant conditions with >90% conversion of nitric oxide at 180 ⁰C (~460 ppm NO and 150 L/g*hr flow rate in the presence of >2% water steam) and TOF ~6,000 hr<sup>-1</sup>. Pd thus outperforms state-of-the-art rhodium containing catalysts with (15-20 times higher rhodium loading; rhodium is ~ 3 times more expensive than palladium). Furthermore, palladium catalysts are more selective towards nitrogen and produce significantly less ammonia relative to the more traditional rhodium catalysts due to lower Pd amount nd lower water-gas-shift activity. Our study is the first example of utilizing ultra-low (0.05 wt% and less) noble metal (Pd) amounts to produce heterogeneous catalysts with extraordinary activity for nitric oxide reduction. This opens up a pathway to study other Pd, Pt and Rh containing materials with ultra-low loadings of expensive noble metals dispersed on titania or titania-coated oxides for industrially relevant nitric oxide abatement.</p>

scholarly journals Cloned, expressed rat cerebellar nitric oxide synthase contains stoichiometric amounts of heme, which binds carbon monoxide.

1992 ◽  
Vol 89 (23) ◽  
pp. 11141-11145 ◽  
Author(s):  
K. McMillan ◽  
D. S. Bredt ◽  
D. J. Hirsch ◽  
S. H. Snyder ◽  
J. E. Clark ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Nitric Oxide Synthase ◽  
Oxide Synthase
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