Abslyut nol harorat


Non-self-sustaining gas discharges


Download 358 Kb.
bet40/44
Sana18.12.2022
Hajmi358 Kb.
#1026830
1   ...   36   37   38   39   40   41   42   43   44
Bog'liq
7.голасарий2019-2020й.

Non-self-sustaining gas discharges are called the electrical conductivity of gases caused by external ionizers.
The gas discharge, which continues after the action of the external ionizer ceases, is called an independent gas discharge.
The arc discharge is a discharge shape at a high current density and a relatively small voltage between the electrodes, on the order of a few tens of volts.
The spark discharge observed at normal pressure and high field strength between the electrodes has the form of discontinuous bright zigzag threads of ionized gas channels.
A special aggregative state of a substance is described as a plasma, characterized by a high degree of ionization of its particles.
The degree of ionization of a substance is the ratio of the concentration of charged particles to the total concentration of particles.
A vacuum is the degree of rarefaction of a gas at which collisions between its molecules can be neglected and the average mean free path l exceeds the linear dimensions d of the vessel in which the gas is located (l ˃˃ d).
The conductivity of the interelectrode gap in the vacuum state is called the electric current in a vacuum.
Thermoelectronic emission is the emission of electrons by solid or liquid bodies when they are heated.
The electrons emitted by the heated body are termed thermoelectrons, and the body itself is emitter.
Secondary electron emission. When a metal surface is bombarded in a vacuum by electrons that are accelerated by an electric field, a counterflow of electrons from the surface is observed. This phenomenon is called secondary electron emission.
Electronic lamps are devices based on the application of the phenomenon of thermionic emission
An electron-beam tube is a device based on the phenomenon of thermionic emission from a heated cathode.
Semiconductors are substances whose specific electric resistance p can vary over a wide range and very rapidly decreases with increasing temperature.
The energy that must be expended to create electrical conductivity in pure semiconductor crystals is called the activation energy of intrinsic conductivity.

Download 358 Kb.

Do'stlaringiz bilan baham:
1   ...   36   37   38   39   40   41   42   43   44




Ma'lumotlar bazasi mualliflik huquqi bilan himoyalangan ©fayllar.org 2024
ma'muriyatiga murojaat qiling