Effect of heating on dissociation of water vapor in high-frequency plasmas and formation of hydrogen peroxide in a cold trap downstream of the plasma

1982 ◽  
Vol 2 (2) ◽  
pp. 157-166 ◽  
Author(s):  
S. Roychowdhury ◽  
U. K. Roychowdhury ◽  
M. Venugopalan
Keyword(s):  
Hydrogen Peroxide ◽  
Water Vapor ◽  
High Frequency ◽  
Cold Trap

REACTIONS IN DISSOCIATED WATER VAPOR

1951 ◽  
Vol 29 (11) ◽  
pp. 996-1009 ◽  
Author(s):  
R. A. Jones ◽  
C. A. Winkler
Keyword(s):  
Hydrogen Peroxide ◽  
Water Vapor ◽  
Room Temperature ◽  
Reaction Chamber ◽  
Glass Wool ◽  
Cold Trap ◽  
Slight Effect ◽  
Reaction Chambers ◽  
Limiting Value ◽  
Water Hydrogen

Water vapor dissociated by an electric discharge and passed into a cold trap yielded products which gave off oxygen at temperatures above −120°C. and at room temperature consisted of hydrogen peroxide and water. With products formed under given conditions, the amount of oxygen evolved with warming was proportional to the total amount of product and independent of the warming procedure. The evolution proceeded to completion at −78°C. Water was found at all trap temperatures between −78°C. and −195°C. Hydrogen peroxide was formed only if the trap temperature was below −120°C., and oxygen was evolved only from products formed below −150°C. The yields of water, hydrogen peroxide, and evolved oxygen all increased with decreasing trap temperature. As the volume of reaction chambers inserted between the discharge tube and the trap was increased, the yield of hydrogen peroxide decreased continuously, while the yield of water at first decreased and then increased to a limiting value. Packing a given reaction chamber with glass wool drastically reduced the yield of hydrogen peroxide, but had little effect on the yield of water. Packing the trap itself had only a slight effect on the yields. The results are compared with those obtained by others with the H–O2 system at low temperatures, and a mechanism is proposed to correlate the two systems.

REACTIONS IN DISSOCIATED PEROXIDE VAPOR

1953 ◽  
Vol 31 (3) ◽  
pp. 262-271 ◽  
Author(s):  
J. S. Batzold ◽  
C. Luner ◽  
C. A. Winkler
Keyword(s):  
Hydrogen Peroxide ◽  
Water Vapor ◽  
Electrical Discharge ◽  
Molecular Hydrogen ◽  
Volume Ratio ◽  
Cold Trap ◽  
Gas Phase Reactions ◽  
Hydrogen Atoms ◽  
A Chain ◽  
Hydrogen Peroxide Vapor

The products of the electrical discharge through hydrogen peroxide vapor were hydrogen peroxide, water, oxygen, and hydrogen, in amounts which depended upon the arrangement and temperature of the trap, reaction time, and surface to volume ratio of the reaction vessel. Water, hydrogen, and oxygen resulted from the gas phase reactions of the dissociated hydrogen peroxide, with hydrogen peroxide produced only in a trap cooled below −120 °C. Products trapped below −150 °C evolved oxygen on warming to room temperature. The decomposition products of the electrical discharge through hydrogen peroxide correspond closely with products obtainable both from a similar discharge through water vapor and from the interaction of hydrogen atoms with oxygen molecules in a cold trap. A mechanism which accounts for their correspondence is included. Water was the only product when molecular hydrogen peroxide was caused to react with hydrogen atoms, dissociated hydrogen peroxide vapor, or dissociated water vapor in the presence or absence of molecular hydrogen. A chain mechanism is postulated for these reactions.

scholarly journals Comparison of the Causes of High-Frequency Heavy and Light Snowfall on Interannual Timescales over Northeast China

Atmosphere ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 936
Author(s):  
Lushan Wang ◽  
Ke Fan ◽  
Zhiqing Xu
Keyword(s):  
Water Vapor ◽  
High Frequency ◽  
Northeast China ◽  
Kuroshio Extension ◽  
Atmospheric Stability ◽  
Northern Eurasia ◽  
Heavy Snowfall ◽  
Air Temperatures ◽  
The Waves ◽  
Water Vapor Budget

This study investigates and compares the reasons for high-frequency heavy and light snowfall in winter on interannual timescales over northeast China (NEC) during 1961–2017. Results indicate that the frequency and its variability are strong over southeastern NEC for heavy snowfall but over northern NEC for light snowfall. Analysis of the annual cycle shows that the maximum frequency of heavy snowfall occurs in November and March due to more warm–wet air masses and increased atmospheric instability, and that of light snowfall occurs in December–January due to drier conditions and increased atmospheric stability. The frequency of heavy snowfall exhibits an increasing trend which partly results from the warming trend in NEC, while that of light snowfall shows a decreasing trend. High-frequency heavy snowfall is associated with a positive North Atlantic Oscillation (NAO), warmer regional air temperatures, an increased water vapor budget associated with an anomalous anticyclone occupying the Kuril Islands, and relatively unstable atmospheric layers. High-frequency light snowfall is associated with a strengthened East Asian winter monsoon, colder regional air temperatures, a decreased water vapor budget, and relatively stable atmospheric layers. High-frequency heavy and light snowfall are both related to eastward-propagating quasi-stationary waves over Eurasia, but with different features. The waves of the former are located in midlatitude Eurasia and related to the positive phase of the NAO. The waves of the latter exhibit two pathways, located in midlatitude and northern Eurasia, respectively. The northern one can be partially attributed to a weak polar vortex. In addition, higher sea surface temperatures of the Kuroshio Extension may contribute to high-frequency heavy snowfall.

Response of Seasonal Simulations of a Regional Climate Model to High-Frequency Variability of Soil Moisture during the Summers of 1988 and 1993

2007 ◽  
Vol 8 (4) ◽  
pp. 738-757 ◽  
Author(s):  
Song Yang ◽  
S-H. Yoo ◽  
R. Yang ◽  
K. E. Mitchell ◽  
H. van den Dool ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Water Vapor ◽  
Diurnal Cycle ◽  
High Frequency ◽  
Large Scale ◽  
Climate Model ◽  
Regional Climate ◽  
Water Vapor Transport ◽  
Diurnal Variability ◽  
High Frequency Variability

Abstract This study employs the NCEP Eta Regional Climate Model to investigate the response of the model’s seasonal simulations of summer precipitation to high-frequency variability of soil moisture. Specifically, it focuses on the response of model precipitation and temperature over the U.S. Midwest and Southeast to imposed changes in the diurnal and synoptic variability of soil moisture in 1988 and 1993. High-frequency variability of soil moisture increases (decreases) precipitation in the 1988 drought (1993 flood) year in the central and southern-tier states, except along the Gulf Coast, but causes smaller changes in precipitation along the northern-tier states. The diurnal variability and synoptic variability of soil moisture produce similar patterns of precipitation change, indicating the importance of the diurnal cycle of land surface process. The increase (decrease) in precipitation is generally accompanied by a decrease (increase) in surface and lower-tropospheric temperatures, and the changes in precipitation and temperature are attributed to both the local effect of evaporation feedback and the remote influence of large-scale water vapor transport. The precipitation increase and temperature decrease in 1988 are accompanied by an increase in local evaporation and, more importantly, by an increase in the large-scale water vapor convergence into the Midwest and Southeast. Analogous but opposite-sign behavior occurs in 1993 (compared to 1988) in changes in precipitation, temperature, soil moisture, evaporation, and large-scale water vapor transport. Results also indicate that, in regions where the model simulates the diurnal cycle of soil moisture reasonably well, including this diurnal cycle in the simulations improves model performance. However, no notable improvement in model precipitation can be found in regions where the model fails to realistically simulate the diurnal variability of soil moisture.

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.

scholarly journals High-Frequency Water Vapor Sorption Cycling Using Fluidization of Metal-Organic Frameworks

2020 ◽  
Vol 1 (5) ◽  
pp. 100057
Author(s):  
Alexandros Terzis ◽  
Ashwin Ramachandran ◽  
Kecheng Wang ◽  
Mehdi Asheghi ◽  
Kenneth E. Goodson ◽  
...  
Keyword(s):  
Water Vapor ◽  
High Frequency ◽  
Metal Organic Frameworks ◽  
Water Vapor Sorption ◽  
Vapor Sorption ◽  
Metal Organic

An Airplane Psychrograph*

1947 ◽  
Vol 28 (8) ◽  
pp. 363-370 ◽  
Author(s):  
Isadore Katz
Keyword(s):  
Water Vapor ◽  
High Frequency ◽  
Radio Waves ◽  
Ultra High Frequency ◽  
Anomalous Propagation

An airplane psychrograph has been designed to make measurements in the lowest several thousand feet of the atmosphere. These measurements are necessary in order to understand the phenomena causing anomalous propagation associated with the ultra-high frequency radio waves used for radar. The instrument employs ceramic resistors as wet and dry elements; they are rapid in response and sensitive enough for measuring sharp gradients of temperature and water vapor usually present close to the boundary between the air and the water or land. Detail of the construction and use of the airplane psychrograph are described.

Studies on Hydrogen–Oxygen Systems in the Electrical Discharge. VII. Deuterium Isotope Effects in the Chemistry of the Hydrogen Polyoxides

1975 ◽  
Vol 53 (16) ◽  
pp. 2490-2497 ◽  
Author(s):  
José L. Arnau ◽  
Paul A. Giguère
Keyword(s):  
Hydrogen Peroxide ◽  
Electrical Discharge ◽  
Microwave Discharge ◽  
Isotope Effects ◽  
Cold Trap ◽  
Manometric Method ◽  
Deuterium Isotope Effects ◽  
Kinetics Of ◽  
Hydrogen Polyoxides ◽  
Hydrogen Peroxide Vapor

The kinetics of oxygen evolution on warming the trapped products (at −196 °C) from water or hydrogen peroxide vapor dissociated in a glow discharge were studied by the manometric method. Under closely controlled conditions it was possible to distinguish clearly the decomposition of the two intermediates, H2O3 and H2O4. The latter begins to decompose measurably following crystallization of the glassy solid at about −115°; the trioxide decomposes readily between −50 and −35°. Typically, the yields of H2O3 from dissociated water vapor were of the order of 3 to 5 mol%; those of H2O4, only about one-tenth as much. Varying the distance between the microwave discharge and the cold trap was found to affect differently the yields of the various products. Those of water and peroxide showed a simple, direct correlation; the minor constituents H2O3 and H2O4 followed entirely different patterns. Only a small fraction of the peroxide is formed via the H2O4 intermediate in these systems. Less water, and more of the higher oxides, were obtained from dissociated hydrogen peroxide than from water vapor.The deuterated systems showed some unusual isotope effects. The yields of D2O3 were always higher (up to twice and even more) than those of H2O3 under similar conditions. The other products showed little or no such effect, except for occluded oxygen and ozone which decreased by about half. Finally, the deuterium polyoxides decompose at slightly higher temperatures (10 to 15°) than their hydrogen analogs. Mechanisms are proposed for the formation and decomposition of the polyoxides.

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