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Thermionic emission from fullerenes
Zeitschrift für Physik D Atoms, Molecules and Clusters, 1993We investigate the time dependence of carbon cluster ions, formed via thermionic emission from photoexcited fullerenes (C60 and C70). By pulsing the extraction field, we are able to observe delayed ions formed as late as 100 µs after excitation at 532 nm, 355 nm, or 266 nm. All even-sized clusters in the range 36 ≤ n ≤ 70 undergo thermionic emission.
Walder, Gerhard +2 more
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THERMIONIC EMISSION FROM FULLERENES
International Journal of Modern Physics B, 1992Fullerenes in the gas phase, excited by a pulsed laser, exhibit thermionic emission. We analyze the time dependence of the ion yield of C n + in a mass spectrometer. By pulsing the extraction field of the ion lens, we are able to observe delayed ions formed as late as 50 µs after excitation by the 2nd, 3rd or 4th harmonic of a Q-switched YAG laser ...
Walder, Gerhard, Echt, Olof
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New Thermionic Emission Microscope
Review of Scientific Instruments, 1966A new thermionic emission microscope has been designed and constructed. It is a two lens microscope having a combination electrostatic-electromagnetic objective lens and an electromagnetic projector lens. The microscope has a magnification range of 78 to 5600× and a resolution of about 500 Å which is independent of magnification.
E. Eichen, R. L. Forgacs, B. A. Parafin
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Bell System Technical Journal, 1935
There have appeared in the Reviews of Modem Physics two excellent summaries on thermionic emission, one by Compton and Langmuir1 and one by Dushman.2 Compton and Lan gmuir, while dealing primarily with discharge in gases, also discussed many phases of thermionic emission. Dushman's article is a comprehensive review on thermionics.
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There have appeared in the Reviews of Modem Physics two excellent summaries on thermionic emission, one by Compton and Langmuir1 and one by Dushman.2 Compton and Lan gmuir, while dealing primarily with discharge in gases, also discussed many phases of thermionic emission. Dushman's article is a comprehensive review on thermionics.
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Thermionic emission from carbon
Proceedings of the Physical Society, 1938Observations of the thermionic emission from a carefully outgassed filament of graphitic carbon were made at a series of temperatures between 1665° and 2191° K. The corresponding values of the constants A and ψ in the empirical emission formula i = AT2exp(-ψ/kT) were found to be 30 amp./cm.2-deg.2 and 4.34 eV. respectively.
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Surface structure of thermionic-emission cathodes
Physical Review Letters, 1987We have used surface extended x-ray absorption fine structure (SEXAFS) to study the local geometry around barium atoms on thermionic cathodes. On the surfaces of tungsten and tungsten-osmium alloy dispenser cathodes Ba is bonded to oxygen with a well-defined short-range order.
, Norman +7 more
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Alternatives to thermionic emission
British Journal of Applied Physics, 1965The main fields of application of thermionic emission are analysed with a view to determining possible advantages of finding alternative approaches. For this purpose a distinction is made between applications where the emitted electrons are employed to transport charge and applications where they are used to transport and convert energy.
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Surface Science Letters, 1982
Abstract A comprehensive theory of thermionic emission from clean metal surfaces is presented. The theory takes into account the energy band structure of the metal, inelastic scattering due to electron-electron collisions and the thermal vibration of the atoms. We applied the theory to thermionic emission from Cu(100).
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Abstract A comprehensive theory of thermionic emission from clean metal surfaces is presented. The theory takes into account the energy band structure of the metal, inelastic scattering due to electron-electron collisions and the thermal vibration of the atoms. We applied the theory to thermionic emission from Cu(100).
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Thermionic Emission into Dielectric Liquids
Physical Review, 1937The presence of thermionic emission at ordinary temperatures for cathodes in contact with dielectric liquids is demonstrated. The current voltage relation is shown to obey the law $I={I}_{0}{e}^{(\frac{\ensuremath{\epsilon}{(\ensuremath{\epsilon}FD)}^{\frac{1}{2}}}{\mathrm{kT}})}$, where $I$ is the current, $F$ the field, and $D$ the dielectric ...
Edward B. Baker, Howard A. Boltz
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Equations for Thermionic Emission
Nature, 1926IN 1923, S. Dushman developed a general equation for thermionic emission, in agreement with the hitherto less frequently used one of the two equations suggested by O. W. Richardson, namely, when i = thermionic current in amp./cm.2. T = absolute temperature. b = constant for the substance. A = a universal constant.
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