The role of hydrogen partial pressure in the gas phase hydrogenation of p-chloronitrobenzene over alumina supported Au and Pd: A consideration of reaction thermodynamics and kinetics

2012 ◽  
Vol 210 ◽  
pp. 103-113 ◽  
Author(s):  
Xiaodong Wang ◽  
Noémie Perret ◽  
Mark A. Keane
Keyword(s):  
Partial Pressure ◽  
Gas Phase ◽  
Hydrogen Partial Pressure ◽  
Thermodynamics And Kinetics ◽  
Reaction Thermodynamics

The role of hydrogen partial pressure on the annealing of copper substrates for graphene CVD synthesis

2016 ◽  
Vol 3 (4) ◽  
pp. 045602 ◽  
Author(s):  
Welyson T S Ramos ◽  
Thiago H R Cunha ◽  
Ingrid D Barcelos ◽  
Douglas R Miquita ◽  
Gustavo A Ferrari ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Hydrogen Partial Pressure ◽  
Cvd Synthesis

Interaction of H2O, O2 and H2 with Proton Conducting Oxides Based on Lanthanum Scandates

2019 ◽  
pp. 88-100
Author(s):  
A. S. Farlenkov ◽  
N. A. Zhuravlev ◽  
Т. A. Denisova ◽  
М. V. Ananyev
Keyword(s):  
Water Vapor ◽  
Partial Pressure ◽  
Gas Phase ◽  
Molecular Hydrogen ◽  
Proton Magnetic Resonance ◽  
Partial Pressure Of Oxygen ◽  
Proton Conducting ◽  
Conducting Oxides ◽  
Temperature Range ◽  
Apparent Level

The research uses the method of high-temperature thermogravimetric analysis to study the processes of interaction of the gas phase in the temperature range 300–950 °C in the partial pressure ranges of oxygen 8.1–50.7 kPa, water 6.1–24.3 kPa and hydrogen 4.1 kPa with La1–xSrxScO3–α oxides (x = 0; 0.04; 0.09). In the case of an increase in the partial pressure of water vapor at a constant partial pressure of oxygen (or hydrogen) in the gas phase, the apparent level of saturation of protons is shown to increase. An increase in the apparent level of saturation of protons of the sample also occurs with an increase in the partial pressure of oxygen at a constant partial pressure of water vapor in the gas phase. The paper discusses the causes of the observed processes. The research uses the hydrogen isotope exchange method with the equilibration of the isotope composition of the gas phase to study the incorporation of hydrogen into the structure of proton-conducting oxides based on strontium-doped lanthanum scandates. The concentrations of protons and deuterons were determined in the temperature range of 300–800 °C and a hydrogen pressure of 0.2 kPa for La0.91Sr0.09ScO3–α oxide. The paper discusses the role of oxygen vacancies in the process of incorporation of protons and deuterons from the atmosphere of molecular hydrogen into the structure of the proton conducting oxides La1–xSrxScO3–α (x = 0; 0.04; 0.09). The proton magnetic resonance method was used to study the local structure in the temperature range 23–110 °C at a rotation speed of 10 kHz (MAS) for La0.96Sr0.04ScO3–α oxide after thermogravimetric measurements in an atmosphere containing water vapor, and after exposures in molecular hydrogen atmosphere. The existence of proton defects incorporated into the volume of the investigated proton oxide from both the atmosphere containing water and the atmosphere containing molecular hydrogen is unambiguously shown. The paper considers the effect of the contributions of the volume and surface of La0.96Sr0.04ScO3–α oxide on the shape of the proton magnetic resonance spectra.

scholarly journals The role of radiolysis in the modelling of C2H4O2 isomers and dimethyl ether in cold dark clouds

2020 ◽  
Vol 500 (3) ◽  
pp. 3414-3424
Author(s):  
Alec Paulive ◽  
Christopher N Shingledecker ◽  
Eric Herbst
Keyword(s):  
Gas Phase ◽  
Dimethyl Ether ◽  
Recent Observation ◽  
Cosmic Ray ◽  
Thermal Method ◽  
Dark Clouds ◽  
Ice Surface ◽  
Dust Grain ◽  
Complex Organic

ABSTRACT Complex organic molecules (COMs) have been detected in a variety of interstellar sources. The abundances of these COMs in warming sources can be explained by syntheses linked to increasing temperatures and densities, allowing quasi-thermal chemical reactions to occur rapidly enough to produce observable amounts of COMs, both in the gas phase, and upon dust grain ice mantles. The COMs produced on grains then become gaseous as the temperature increases sufficiently to allow their thermal desorption. The recent observation of gaseous COMs in cold sources has not been fully explained by these gas-phase and dust grain production routes. Radiolysis chemistry is a possible non-thermal method of producing COMs in cold dark clouds. This new method greatly increases the modelled abundance of selected COMs upon the ice surface and within the ice mantle due to excitation and ionization events from cosmic ray bombardment. We examine the effect of radiolysis on three C2H4O2 isomers – methyl formate (HCOOCH3), glycolaldehyde (HCOCH2OH), and acetic acid (CH3COOH) – and a chemically similar molecule, dimethyl ether (CH3OCH3), in cold dark clouds. We then compare our modelled gaseous abundances with observed abundances in TMC-1, L1689B, and B1-b.

Role of solid- and gas-phase interactions in the coaction of the oxides in MnO2 + PbO and MnO2 + V2O5 compositions activating the thermal oxidation of GaAs

2007 ◽  
Vol 52 (10) ◽  
pp. 1498-1502 ◽  
Author(s):  
V. F. Kostryukov ◽  
V. R. Pshestanchik ◽  
I. A. Donkareva ◽  
B. L. Agapov ◽  
S. I. Lopatin ◽  
...  
Keyword(s):  
Thermal Oxidation ◽  
Gas Phase

Singlet oxygen feedback delayed fluorescence of protoporphyrin IX in organic solutions

2017 ◽  
Vol 16 (4) ◽  
pp. 507-518 ◽  
Author(s):  
Ivo S. Vinklárek ◽  
Marek Scholz ◽  
Roman Dědic ◽  
Jan Hála
Keyword(s):  
Partial Pressure ◽  
Singlet Oxygen ◽  
Protoporphyrin Ix ◽  
Clinical Applications ◽  
Delayed Fluorescence ◽  
Diagnostic Tools ◽  
Partial Pressure Of Oxygen ◽  
High Concentrations ◽  
Organic Solutions

The PpIX DF show the significant role of SOFDF mechanism at high concentrations and at atmospheric partial pressure of oxygen and should be considered when developing diagnostic tools for clinical applications.

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