Original In-Situ Method to Quantify the SiC Active Corrosion Rate and Active/Passive Transition in Ar/O2and Ar/H2O Gas Mixtures at Very High Temperatures

Author(s):  
Mathieu Q. Brisebourg ◽  
Bernard Boilait ◽  
Francis Rebillat ◽  
Francis Teyssandier
1995 ◽  
Vol 404 ◽  
Author(s):  
T. Kamino ◽  
H. Saka

AbstractA specimen-heating holder which allows an observation of reactions of more than one materials, in a controlled manner, at such a high temperature as 1723K has been developed. Facet-unfacet transformation and reconstruction of Au-deposited Si surfaces have been observed at very high temperatures at near-atomic resolution.


1997 ◽  
Vol 3 (5) ◽  
pp. 393-408 ◽  
Author(s):  
T. Kamino ◽  
K. Sasaki ◽  
H. Saka

High Resolution Electron Microscopy In Situ Observation of Dynamic Behavior of Grain Boundaries and Interfaces at Very High Temperatures


Author(s):  
Z. L. Wang ◽  
J. Bentley

Studying the behavior of surfaces at high temperatures is of great importance for understanding the properties of ceramics and associated surface-gas reactions. Atomic processes occurring on bulk crystal surfaces at high temperatures can be recorded by reflection electron microscopy (REM) in a conventional transmission electron microscope (TEM) with relatively high resolution, because REM is especially sensitive to atomic-height steps.Improved REM image resolution with a FEG: Cleaved surfaces of a-alumina (012) exhibit atomic flatness with steps of height about 5 Å, determined by reference to a screw (or near screw) dislocation with a presumed Burgers vector of b = (1/3)<012> (see Fig. 1). Steps of heights less than about 0.8 Å can be clearly resolved only with a field emission gun (FEG) (Fig. 2). The small steps are formed by the surface oscillating between the closely packed O and Al stacking layers. The bands of dark contrast (Fig. 2b) are the result of beam radiation damage to surface areas initially terminated with O ions.


2019 ◽  
Author(s):  
Przemyslaw Rzepka ◽  
Zoltán Bacsik ◽  
Andrew J. Pell ◽  
Niklas Hedin ◽  
Aleksander Jaworski

Formation of CO<sub>3</sub><sup>2-</sup> and HCO<sub>3</sub><sup>-</sup> species without participation of the framework oxygen atoms upon chemisorption of CO<sub>2</sub> in zeolite |Na<sub>12</sub>|-A is revealed. The transfer of O and H atoms is very likely to have proceeded via the involvement of residual H<sub>2</sub>O or acid groups. A combined study by solid-state <sup>13</sup>C MAS NMR, quantum chemical calculations, and <i>in situ</i> IR spectroscopy showed that the chemisorption mainly occurred by the formation of HCO<sub>3</sub><sup>-</sup>. However, at a low surface coverage of physisorbed and acidic CO<sub>2</sub>, a significant fraction of the HCO<sub>3</sub><sup>-</sup> was deprotonated and transformed into CO<sub>3</sub><sup>2-</sup>. We expect that similar chemisorption of CO<sub>2</sub> would occur for low-silica zeolites and other basic silicates of interest for the capture of CO<sub>2</sub> from gas mixtures.


Author(s):  
Debashis Mukherji ◽  
Joachim Rösler ◽  
Pavel Strunz ◽  
Ralph Gilles ◽  
Gerhard Schumacher ◽  
...  

Alloy Digest ◽  
1963 ◽  
Vol 12 (8) ◽  

Abstract Cooper Alloy 22W is a high strength, heat resistant casting alloy with a low creep rate. It is recommended for heat applications where stress and hot gas corrosion rate are very high. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, joining, and surface treatment. Filing Code: SS-146. Producer or source: Cooper Alloy Corporation.


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