Residual Argon Partial Pressure Changes due to an Intermittently Operated Bayard–Alpert Ionization Gauge in Ultrahigh Vacuum

1964 ◽  
Vol 1 (1) ◽  
pp. 17-18 ◽  
Author(s):  
M. Friedman Axler
Keyword(s):  
Partial Pressure ◽  
Ultrahigh Vacuum ◽  
Ionization Gauge ◽  
Pressure Changes

The deuterium interaction with tungsten and iridium in the UHV system

1985 ◽  
Vol 50 (12) ◽  
pp. 2656-2664
Author(s):  
Karel Kuchynka ◽  
Zlatko Knor
Keyword(s):  
Partial Pressure ◽  
Chemical Reactions ◽  
Pressure Range ◽  
Tungsten Filament ◽  
Different Temperatures ◽  
Pressure Changes

The behaviour of hydrogen, in its contact with the iridium and the tungsten filament kept at different temperatures, was studied in the pressure range 1.3 . 10-6 - 1.3 . 10-3 Pa, in a glass apparatus. The effects of adsorption, atomization, desorption, recombination of atoms and chemical reactions were investigated as a function of temperature of the filaments. The named individual processes were used for interpretation of the partial pressure changes in the apparatus. The significance of the above individual phenomena in the UHV experiments is pointed out in this paper.

Influences of oxygen impurity contained in nitrogen gas on the reactions of chromium with nitrogen

2005 ◽  
Vol 20 (10) ◽  
pp. 2745-2753 ◽  
Author(s):  
Yung-Shou Ho ◽  
Fong-Shung Huang ◽  
Fu-Hsing Lu
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Oxygen Impurity ◽  
Nitrogen Gas ◽  
Available Nitrogen ◽  
Increasing Temperature ◽  
Pressure Changes ◽  
Annealing Experiments ◽  
Simultaneous Dissolution

In this research, the influences of the oxygen impurity contained in the commercially available nitrogen gas on the reactions of chromium pellets with nitrogen were investigated in the temperature range 600–1350 °C. A small amount of oxygen competed with the majority N2 to react with chromium in the annealing process. Analyzing the in situ oxygen partial pressure changes during annealing proved that the dissolution of oxygen in Cr and/or resultant CrxN (CrN or Cr2N) was exothermic and the solubility decreased with increasing temperature. It was found that the oxygen partial pressure decreased drastically to about 10−22 atm when specimens were annealed at 600 °C compared to a mere 10−5 atm for a blank test, while its value increased with temperature. The oxidation involved simultaneous dissolution of oxygen in specimens and formation of oxide scale. Moreover, comparing the aforementioned results with those obtained from additional annealing experiments preformed in argon gas showed that the formation of Cr2O3 might stem mainly from oxidation of the resultant nitrides instead of the metallic chromium.

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