The Reactions of the Hydroxyl Radical in the Electrodeless Discharge in Water Vapor

1933 ◽  
Vol 1 (10) ◽  
pp. 696-702 ◽  
Author(s):  
W. H. Rodebush ◽  
M. H. Wahl
Keyword(s):  
Water Vapor ◽  
Hydroxyl Radical ◽  
Electrodeless Discharge

Studies on hydrogen–oxygen systems in the electrical discharge. III. Surface effects

1970 ◽  
Vol 48 (13) ◽  
pp. 2042-2046 ◽  
Author(s):  
Paul E. Brunet ◽  
Xavier Deglise ◽  
Paul A. Giguère
Keyword(s):  
Hydrogen Peroxide ◽  
Water Vapor ◽  
Power Level ◽  
Surface Effects ◽  
Surface Coatings ◽  
Pure Hydrogen ◽  
Pyrolysis Products ◽  
Electrodeless Discharge ◽  
Oxygen Gas ◽  
Hydrogen Peroxide Vapor

Surface effects in the reactions of dissociated hydrogen–oxygen systems and the products condensed therefrom have been investigated. Water vapor at about 0.1 Torr was streamed at high velocity through an electrodeless discharge confined in tubes of different materials or with various surface coatings. In all cases the products trapped in liquid nitrogen evolved oxygen gas on warming, but the relative amounts varied considerably from one type of surface to another. In some cases there was clear evidence that the walls of discharge tube were attacked by hydrogen atom bombardment. The decomposition, both thermal and electrical, of pure hydrogen peroxide vapor was studied likewise. The pyrolysis products gave off very little oxygen on warming. By contrast the products from electrical decomposition, even at low power level, evolved much oxygen, most of it above the melting point.It is concluded that there is always some decomposition of hydrogen peroxide in the trapped products. However, this does not seem sufficient to account for all the evolved oxygen; at least not in the case of dissociated water vapor.

Hydroxyl Radical Fluorescence and Quantum Yield Following Lyman-α Photoexcitation of Water Vapor in a Room Temperature Cell and Cooled in a Supersonic Expansion

2018 ◽  
Vol 122 (25) ◽  
pp. 5602-5609 ◽  
Author(s):  
Justin W. Young ◽  
Ryan S. Booth ◽  
Kristen M. Vogelhuber ◽  
Jaime A. Stearns ◽  
Christopher J. Annesley
Keyword(s):  
Water Vapor ◽  
Quantum Yield ◽  
Hydroxyl Radical ◽  
Room Temperature ◽  
Supersonic Expansion

Study on production of hydroxyl radical by DBD in argon added water vapor

2017 ◽  
Vol 2017.55 (0) ◽  
pp. K0704
Author(s):  
Keiichi SAKATA ◽  
Shinobu MUKASA ◽  
Shinji NAGAO ◽  
Hiromichi TOYOTA ◽  
Shinfuku NOMURA
Keyword(s):  
Water Vapor ◽  
Hydroxyl Radical ◽  
Added Water

Formation of the vibrationally excited hydroxyl radical by electron impact of water vapor

1982 ◽  
Vol 86 (8) ◽  
pp. 1427-1428 ◽  
Author(s):  
Iwao Fujita ◽  
Jun Tamaki ◽  
Toshio Kasai ◽  
Kiyoshi Fukui ◽  
Keiji Kuwata
Keyword(s):  
Water Vapor ◽  
Hydroxyl Radical ◽  
Electron Impact ◽  
Vibrationally Excited

STUDIES ON HYDROGEN–OXYGEN SYSTEMS IN THE ELECTRIC DISCHARGE: I. THE REACTIONS OF HYDROGEN ATOMS WITH HYDROGEN PEROXIDE

1966 ◽  
Vol 44 (8) ◽  
pp. 869-876 ◽  
Author(s):  
Norisuke H Ata ◽  
Paul A. Glguère
Keyword(s):  
Hydrogen Peroxide ◽  
Water Vapor ◽  
Electric Discharge ◽  
Hydrogen Gas ◽  
Reaction Products ◽  
Hydrogen Atoms ◽  
Eutectic Melting ◽  
Electrodeless Discharge ◽  
Liquid Nitrogen Trap ◽  
Unidentified Species

Hydrogen gas partly dissociated in an electrodeless discharge was mixed downstream with hydrogen peroxide vapor at low pressure (0.1 mm Hg) in a liquid nitrogen trap. The reaction products condensed readily on the wall as a clear, yellowish glass resembling that from dissociated water vapor and other related systems. A manometric study of the warming-up process has revealed four distinct steps. The first two, in which only traces of gas are given off, look like the recombination of trapped free radicals. The major evolution of oxygen upon crystallization of the glassy deposit at 160 °K is ascribed to the decomposition of hydrogen peroxide under the influence of some unidentified species generated in the electric discharge through hydrogen. Experimental evidence for this is presented. In any case the stoichiometry cannot be reconciled with the formation of a metastable intermediate, such as the hypothetical polyoxide H2O4.In the last step beginning around 215 °K more peroxide is decomposed during the eutectic melting of the solid. Qualitatively these phenomena are similar to those shown by the condensate from dissociated water vapor.

scholarly journals A Machine Learning Examination of Hydroxyl Radical Differences Among Model Simulations for CCMI-1

2019 ◽  
Author(s):  
Julie M. Nicely ◽  
Bryan N. Duncan ◽  
Thomas F. Hanisco ◽  
Glenn M. Wolfe ◽  
Ross J. Salawitch ◽  
...  
Keyword(s):  
Water Vapor ◽  
Hydroxyl Radical ◽  
Climate Model ◽  
Uv Light ◽  
Temporal Trends ◽  
Historical Simulation ◽  
Sources And Sinks ◽  
Chemical Mechanisms ◽  
Photolysis Frequency ◽  
Dynamics Simulations

Abstract. Hydroxyl radical (OH) plays critical roles within the troposphere, such as determining the lifetime of methane (CH4), yet is challenging to model due to its fast cycling and dependence on a multitude of sources and sinks. As a result, the reasons for variations in OH and the resulting CH4 lifetime (τCH4), both between models and in time, are difficult to diagnose. We apply a neural network (NN) approach to address this issue within a group of models that participated in the Chemistry-Climate Model Initiative (CCMI). Analysis of the historical specified dynamics simulations performed for CCMI indicates that the primary drivers of τCH4 differences among ten models are the flux of UV light to the troposphere (indicated by the photolysis frequency JO1D) due mostly to clouds, mixing ratio of tropospheric ozone (O3), the abundance of nitrogen oxides (NOx≡NO+NO2), and details of the various chemical mechanisms that drive OH. Water vapor, carbon monoxide (CO), the ratio of NO:NOx, and formaldehyde (HCHO) explain moderate differences in τCH4, while isoprene, CH4, the photolysis frequency of NO2 by visible light (JNO2), overhead O3 column, and temperature account for little-to-no model variation in τCH4. We also apply the NNs to analysis of temporal trends in OH from 1980 to 2015. All models that participated in the specified dynamics historical simulation for CCMI demonstrate a decline in τCH4 during the analysed timeframe. The significant contributors to this trend, in order of importance, are tropospheric O3, JO1D, NOx, and H2O, with CO also causing substantial interannual variability in OH burden. Finally, the identified trends in τCH4 are compared to calculated trends in the tropospheric mean OH concentration from previous work, based on analysis of observations. The comparison reveals a robust result for the effect of rising water vapor on OH and τCH4, imparting an increasing and decreasing trend of about 0.5 % decade−1, respectively. The responses due to NOx, O3 column, and temperature are also in reasonably good agreement between the two studies, though a discrepancy in the CH4 response highlights a need for further examination of the CH4 feedback on the abundance of OH.

scholarly journals Spatial and temporal variability of the hydroxyl radical: Understanding the role of large-scale climate features and their influence on OH through its dynamical and photochemical drivers

2020 ◽  
Author(s):  
Daniel C. Anderson ◽  
Bryan N. Duncan ◽  
Arlene M. Fiore ◽  
Colleen B. Baublitz ◽  
Melanie B. Follette-Cook ◽  
...  
Keyword(s):  
Water Vapor ◽  
Climate Variability ◽  
Hydroxyl Radical ◽  
Southern Oscillation ◽  
Satellite Observations ◽  
Spatial And Temporal Variability ◽  
Upper Troposphere ◽  
Modes Of Variability ◽  
The Relationship ◽  
Modes Of Climate Variability

Abstract. The hydroxyl radical (OH) is the primary atmospheric oxidant, responsible for removing many important trace gases, including methane, from the atmosphere. Although robust relationships between OH drivers and modes of climate variability have been shown, the underlying mechanisms between OH and these climate modes, such as the El Niño Southern Oscillation (ENSO), have not been thoroughly investigated. Here, we use a chemical transport model to perform a 38-year simulation of atmospheric chemistry, in conjunction with satellite observations, to understand the relationship between tropospheric OH and ENSO, Northern Hemispheric modes of variability, the Indian Ocean Dipole, and monsoons. Empirical orthogonal function (EOF) and regression analyses show that ENSO is the dominant mode of global OH variability in the tropospheric column and upper troposphere, responsible for approximately 30 % of the total variance in boreal winter. Reductions in OH due to ENSO are centered over the tropical Pacific and Australia and can be as high as 10–15 % in the tropospheric column. The relationship between ENSO and OH is driven by changes in nitrogen oxides in the upper troposphere and changes in water vapor and O1D in the lower troposphere. While the spatial scale of the relationship between monsoons, other modes of variability, and OH are much smaller than ENSO, local changes in OH can be significantly larger than those caused by ENSO. These relationships also occur in multiple models that participated in the Chemistry Climate Model Initiative (CCMI), suggesting that the dependence of OH interannual variability on these well-known modes of climate variability is robust. Finally, modeled relationships between ENSO and OH drivers – such as carbon monoxide, water vapor, and lightning – closely agree with satellite observations. The ability of satellite products to capture the relationship between OH drivers and ENSO provides an avenue to an indirect OH observation strategy and new constraints on OH variability.

The gas-phase reaction of methane sulfonic acid with the hydroxyl radical without and with water vapor

2013 ◽  
Vol 15 (14) ◽  
pp. 5140 ◽  
Author(s):  
Solvejg Jørgensen ◽  
Camilla Jensen ◽  
Henrik G. Kjaergaard ◽  
Josep M. Anglada
Keyword(s):  
Water Vapor ◽  
Hydroxyl Radical ◽  
Gas Phase ◽  
Sulfonic Acid ◽  
Phase Reaction ◽  
Methane Sulfonic Acid ◽  
Gas Phase Reaction
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