A. K. Mazumdar's research while affiliated with Philipps University of Marburg and other places

Publications (2)

Article
Interaction of oxygen with a polycrystalline tungsten surface has been mass-spectrometrically studied both under transient (flash filament with single flight detection) and steady-state (constant flow) conditions at temperatures T between 1000 K and 2500 and at oxygen pressures po2 from 10−9 to 10−6 torr. Only one binding state each for atomic oxyg...
Article
The adsorption lifetime τ and the desorption energy Q of oxygen atoms on a polycrystalline tungsten surface have been determined as functions of the coverage θ by using a uhv mass spectrometer. A method based on contact potential and sticking probability measurements (T=1200–2500  K ) , a combined study of steady state and transient state desorptio...

Citations

... The rate of mass transport depends on several factors: partial pressures and type of contaminants; removal rate of gaseous contaminants from the interelectrode gap; and temperatures and materials of the electrodes. Data on mass loss of most common electrode materials (tungsten and molybdenum) (Kofstad 1988, Mazumdar and Wassmuth 1972, Walsh et al. 1967 showed that the mass loss rate of emitter material depends primarily on the amount of oxygen and oxygen bearing contaminants such as water vapor, cesium hydroxide, and carbon and cesium oxides. Other species such as hydrogen, nitrogen, carbon and cesium can also affect the rate of the emitter material loss. ...