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Gas Focusing
Gas focusing, also known as ionic focusing. Rather than being dispersed, a beam of charged particles travelling in an inert gas environment sometimes becomes narrower. This is ascribed to the generation of gas ions which diffuse outwards, neutralizing the particle beam globally, and producing an intense radial electric field which applies a radially inward force to the particles in the beam. See also * Vacuum tube * Teleforce Teleforce is a proposed defensive weapon by Nikola Tesla that accelerated pellets or slugs of material to a high velocity inside a vacuum chamber via electrostatic repulsion and then fired them out of aimed nozzles at intended targets. Tesla clai ... References * Sabchevski S P and Mladenov G M 1994 ''J. Physics D: Applied Physics'' 27 690-697 ** Mladenov G., and Sabchevski S., Potential distribution and space-charge neutralization in intense electron beams - an overview "Vacuum", 2001,v62, N2-3, pp. 113–122 External links Ionic focusing Pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inert Gas
An inert gas is a gas that does not readily undergo chemical reactions with other chemical substances and therefore does not readily form chemical compounds. The noble gases often do not react with many substances and were historically referred to as the inert gases. Inert gases are used generally to avoid unwanted chemical reactions degrading a sample. These undesirable chemical reactions are often oxidation and hydrolysis reactions with the oxygen and moisture in air. The term ''inert gas'' is context-dependent because several of the noble gases can be made to react under certain conditions. Purified argon gas is the most commonly used inert gas due to its high natural abundance (78.3% N2, 1% Ar in air) and low relative cost. Unlike noble gases, an inert gas is not necessarily elemental and is often a compound gas. Like the noble gases, the tendency for non-reactivity is due to the valence, the outermost electron shell, being complete in all the inert gases. This is a tendency, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Field
An electric field (sometimes E-field) is the physical field that surrounds electrically charged particles and exerts force on all other charged particles in the field, either attracting or repelling them. It also refers to the physical field for a system of charged particles. Electric fields originate from electric charges and time-varying electric currents. Electric fields and magnetic fields are both manifestations of the electromagnetic field, one of the four fundamental interactions (also called forces) of nature. Electric fields are important in many areas of physics, and are exploited in electrical technology. In atomic physics and chemistry, for instance, the electric field is the attractive force holding the atomic nucleus and electrons together in atoms. It is also the force responsible for chemical bonding between atoms that result in molecules. The electric field is defined as a vector field that associates to each point in space the electrostatic ( Coulomb) for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental electronic functions such as signal amplifier, amplification and current rectifier, rectification. Non-thermionic types such as a vacuum phototube, however, achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light intensities. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube. The simplest vacuum tube, the diode (i.e. Fleming valve), invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through the device—fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleforce
Teleforce is a proposed defensive weapon by Nikola Tesla that accelerated pellets or slugs of material to a high velocity inside a vacuum chamber via electrostatic repulsion and then fired them out of aimed nozzles at intended targets. Tesla claimed to have conceived of it after studying the Van de Graaff generator. Tesla described the weapon as being able to be used against ground-based infantry or for anti-aircraft purposes. Description Tesla described ''Teleforces operation in 1934, specifying its superiority to the death rays believed to exist at the time: My apparatus projects particles which may be relatively large or of microscopic dimensions, enabling us to convey to a small area at a great distance trillions of times more energy than is possible with rays of any kind. Many thousands of horsepower can thus be transmitted by a stream thinner than a hair, so that nothing can resist. The nozzle would send concentrated beams of particles through the free air, of such tremendou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
