Tuning the Adsorption Energy of Methanol Molecules Along Ni-N-Doped Carbon Phase Boundaries by the Mott-Schottky Effect for Gas-Phase Methanol Dehydrogenation

2018 ◽  
Vol 57 (10) ◽  
pp. 2697-2701 ◽  
Author(s):  
Zhong-Hua Xue ◽  
Jing-Tan Han ◽  
Wei-Jie Feng ◽  
Qiu-Ying Yu ◽  
Xin-Hao Li ◽  
...  
Keyword(s):  
Gas Phase ◽  
Adsorption Energy ◽  
Phase Boundaries ◽  
Methanol Dehydrogenation ◽  
Carbon Phase ◽  
Schottky Effect

Tuning the Adsorption Energy of Methanol Molecules Along Ni-N-Doped Carbon Phase Boundaries by the Mott-Schottky Effect for Gas-Phase Methanol Dehydrogenation

2018 ◽  
Vol 130 (10) ◽  
pp. 2727-2731 ◽  
Author(s):  
Zhong-Hua Xue ◽  
Jing-Tan Han ◽  
Wei-Jie Feng ◽  
Qiu-Ying Yu ◽  
Xin-Hao Li ◽  
...  
Keyword(s):  
Gas Phase ◽  
Adsorption Energy ◽  
Phase Boundaries ◽  
Methanol Dehydrogenation ◽  
Carbon Phase ◽  
Schottky Effect

Simulation of Coal Conversion Reactor Environments

CORROSION ◽  
1980 ◽  
Vol 36 (4) ◽  
pp. 167-173 ◽  
Author(s):  
RICHARD A. COOKE ◽  
OWEN F. DEVEREUX
Keyword(s):  
Gas Phase ◽  
Equilibrium Constants ◽  
Multiple Equilibrium ◽  
Carbon Phase ◽  
Coal Gas ◽  
Coal Gasifier ◽  
Molten Sodium ◽  
Partial Pressures ◽  
Activity Ratios ◽  
Salt Phase

Abstract Two models simulating the coal gasifier environment are described; Model 1 comprises coal gas components and a molten sodium salt phase, while Model 2 also includes a solid carbon phase. The use of equilibrium constants to compute the equilibrium state of an open system and the occurrence of multiple equilibrium states are detailed. Representative computations pertaining to the two models are shown in which dependent partial pressures and activity ratios are computed as function of temperature, total pressure, and the partial pressures of hydrogen, carbon monoxide, and hydrogen sulfide. The dominant anion in the liquid phase is mapped as a function of equilibrium gas phase composition.

scholarly journals Does Symmetry Control Photocatalytic Activity of Titania-Based Photocatalysts?

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1682
Author(s):  
Marcin Janczarek ◽  
Zhishun Wei ◽  
Tharishinny R. Mogan ◽  
Lei Wang ◽  
Kunlei Wang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Gas Phase ◽  
Water Oxidation ◽  
Photocatalytic Performance ◽  
Phase Method ◽  
Inverse Opal ◽  
Methanol Dehydrogenation ◽  
Reaction Systems ◽  
Gold Nps ◽  
Particle Aspect Ratio

Decahedral anatase particles (DAPs) have been prepared by the gas-phase method, characterized, and analyzed for property-governed photocatalytic activity. It has been found that depending on the reaction systems, different properties control the photocatalytic activity, that is, the particle aspect ratio, the density of electron traps and the morphology seem to be responsible for the efficiency of water oxidation, methanol dehydrogenation and oxidative decomposition of acetic acid, respectively. For the discussion on the dependence of the photocatalytic activity on the morphology and/or the symmetry other titania-based photocatalysts have also been analyzed, that is, octahedral anatase particles (OAP), commercial titania P25, inverse opal titania with and without incorporated gold NPs in void spaces and plasmonic photocatalysts (titania with deposits of gold). It has been concluded that though the morphology governs photocatalytic activity, the symmetry (despite its importance in many cases) rather does not control the photocatalytic performance.

scholarly journals Segregation effect and N2 binding energy reduction in CO-N2 systems adsorbed on water ice substrates

2018 ◽  
Vol 619 ◽  
pp. A111 ◽  
Author(s):  
T. Nguyen ◽  
S. Baouche ◽  
E. Congiu ◽  
S. Diana ◽  
L. Pagani ◽  
...  
Keyword(s):  
Binding Energy ◽  
Gas Phase ◽  
Adsorption Energy ◽  
High Vacuum ◽  
Amorphous Solid ◽  
Abundant Species ◽  
Binding Energies ◽  
Ultra High Vacuum ◽  
Pure Species ◽  
Water Ice

Context. CO and N2 are two abundant species in molecular clouds. CO molecules are heavily depleted from the gas phase towards the centre of pre-stellar cores, whereas N2 maintains a high gas phase abundance. For example, in the molecular cloud L183, CO is depleted by a factor of ≈400 in its centre with respect to the outer regions of the cloud, whereas N2 is only depleted by a factor of ≈20. The reason for this difference is not yet clear, since CO and N2 have identical masses, similar sticking properties, and a relatively close energy of adsorption. Aims. We present a study of the CO-N2 system in sub-monolayer regimes, with the aim to measure, analyse and elucidate how the adsorption energy of the two species varies with coverage, with much attention to the case where CO is more abundant than N2. Methods. Experiments were carried out using the ultra-high vacuum (UHV) set-up called VENUS. Sub-monolayers of either pure 13CO or pure 15N2 and 13CO:15N2 mixtures were deposited on compact amorphous solid water ice, and crystalline water ice. Temperature-programmed desorption experiments, monitored by mass spectrometry, are used to analyse the distributions of binding energies of 13CO and 15N2 when adsorbed together in different proportions. Results. The distribution of binding energies of pure species varies from 990 K to 1630 K for 13CO, and from 890 K to 1430 K for 15N2. When a CO:N2 mixture is deposited, the 15N2 binding energy distribution is strongly affected by the presence of 13CO, whereas the adsorption energy of CO is unaltered. Conclusions. Whatever types of water ice substrate we used, the N2 effective binding energy was significantly lowered by the presence of CO molecules. We discuss the possible impact of this finding in the context of pre-stellar cores.

Residual Gas Reactions in the Electron Microscope: I. Qualitative Observations on the Water Gas Reaction

1968 ◽  
Vol 26 ◽  
pp. 292-293
Author(s):  
Richard E. Hartman ◽  
Roberta S. Hartman ◽  
Peter L. Ramos
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Gas Phase ◽  
Absolute Temperature ◽  
Residual Gas ◽  
Gas Reactions ◽  
Image Position ◽  
The Right ◽  
Water Gas ◽  
Thinning Rate

The action of water and the electron beam on organic specimens in the electron microscope results in the removal of oxidizable material (primarily hydrogen and carbon) by reactions similar to the water gas reaction .which has the form:The energy required to force the reaction to the right is supplied by the interaction of the electron beam with the specimen.The mass of water striking the specimen is given by:where u = gH2O/cm2 sec, PH2O = partial pressure of water in Torr, & T = absolute temperature of the gas phase. If it is assumed that mass is removed from the specimen by a reaction approximated by (1) and that the specimen is uniformly thinned by the reaction, then the thinning rate in A/ min iswhere x = thickness of the specimen in A, t = time in minutes, & E = efficiency (the fraction of the water striking the specimen which reacts with it).

Growth of spinel into alumina

1987 ◽  
Vol 45 ◽  
pp. 294-295
Author(s):  
Y. Kouh Simpson ◽  
C. B. Carter
Keyword(s):  
Misfit Dislocations ◽  
Phase Boundaries ◽  
Large Rotation ◽  
Alumina Phase ◽  
Metallic Interfaces ◽  
Small Rotation

The structure of spinel/alumina phase boundaries has recently been studied using the selected- area diffraction technique. It has been found that there exist several dominant topotactic relationships; of these, the two most common situations are when the {111} plane of spinel is parallel to either the (0001) plane or the {1120} plane of alumina. In both of these cases, it has been found that there is often a small rotation from exact topotaxy (typically 0° to 2° but with larger rotations possible) which partially eliminates the need for misfit dislocations. This rotation is a special phenomenon that may be unique to non-metallic interfaces such as phase boundaries in ceramics. In this report, a special spinel/alumina interface in which a large rotation from the exact topotaxy exists between the (111) plane of spinel and the (OOOl) plane of alumina is discussed.

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