Journal ArticleDOI
Modelling of barium transport in dispenser cathodes
Anjan Sil,D.S. Venkateswarlu +1 more
TLDR
In this article, a theoretical model of the diffusion of barium from the generating to the emitting sites of the cathode has been developed from the general considerations of diffusion as well as the fundamental nature of the barium surface migration.About:
This article is published in Applied Surface Science.The article was published on 1994-12-01. It has received 2 citations till now. The article focuses on the topics: Barium & Surface diffusion.read more
Citations
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Journal ArticleDOI
Uniformity Investigation of Barium Tungsten Cathode With Spherical Powder
TL;DR: In this paper, a barium tungsten (Ba-W) cathode was successfully prepared with spherical W powder, and the porous matrix exhibited homogeneous pore distribution and good inter-pore connectivity.
Journal ArticleDOI
Modeling of Barium Coverage and Electron Emission From a Controlled-Porosity Dispenser Cathode
TL;DR: In this article, a mathematical model was developed to estimate the dynamic coverage of barium on the surface of a controlled-porosity dispenser (CPD) cathode, considering the cumulative barium coverage due to all the neighboring pores and loss of the barium due to evaporation.
References
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Journal ArticleDOI
Surface studies of barium and barium oxide on tungsten and its application to understanding the mechanism of operation of an impregnated tungsten cathode
TL;DR: In this paper, the surface conditions of an activated impregnated tungsten cathode were synthesized to obtain a better understanding of the mechanism of operation of such cathodes.
Journal ArticleDOI
Adsorption of Strontium and of Barium on Tungsten
George E. Moore,H. W. Allison +1 more
TL;DR: In this paper, the adsorption mechanism was shown to be a reversible function of the amount adsorbed by using radioactive Sr isotopes, and the deposit corresponding to any thermionic activation was measured.
Journal ArticleDOI
Studies on the Mechanism of Operation of the L Cathode. II
TL;DR: In this paper, an experimental study of the L cathode is presented, including the chemistry of carbonate decomposition and barium generation, the origin of BaO in the evaporant, the barium transport mechanism through the porous plug, and the factors determining cathode life.
Journal ArticleDOI
Surface structure of thermionic-emission cathodes.
D. Norman,R.A. Tuck,H.B. Skinner,P.J. Wadsworth,T.M. Gardiner,I.W. Owen,C.H. Richardson,G. Thornton +7 more
TL;DR: In this article, the authors used surface extended x-ray absorption fine structure (SEXAFS) to study the local geometry around barium atoms on thermionic cathodes.
Journal ArticleDOI
Auger electron spectroscopy study of cathode surfaces during activation and poisoning. I. The barium‐on‐oxygen‐on‐tungsten dispenser cathode
R. W. Springer,T. W. Haas +1 more
TL;DR: In this paper, the chemical changes taking place on a commonly used dispenser cathode have been carried out during activation and poisoning by several reactive gases (O2, CO, CO2, H2, N2, Ar).