Getters in vacuum tubes

Rubidium forms numerous compounds, but only a few are useful. One of the main uses for rubidium is as a getter in vacuum tubes used in early radios, TVs, and cathode-ray tubes. These kinds of tubes work best if all the air is removed, so a getter absorbs the remaining few atoms of air that cannot be removed mechanicahy by vacuum pumps, thus extending the hfe of the vacuum tube. 

Because of its hardness and noncorrosiveness, tantalum is used to make dental and surgical tools and implants and artificial joints, pins, and screws. The metal does not interact with human tissues and fluids. Since tantalum can be drawn into thin wires, it is used in the electronics industry, to make smoke detectors, as a getter in vacuum tubes to absorb residual gases, and as filaments in incandescent lamps. It has many other uses in the electronics industry. 

Misch metal, an alloy of cerium with other lanthanides is a pyrophoric substance and is used to make gas lighters and ignition devices. Some other applications of the metal or its alloys are in solid state devices rocket propellant compositions as getter in vacuum tubes and as a diluent for plutonium in nuclear fuel. 

The most important applications of zirconium involve its alloys, Zircaloy. The aUoy offers excellent mechanical and heat-transfer properties and great resistance to corrosion and chemical attack. This, in conjunction with the fact that zirconium has a low neutron absorption cross section, makes this ahoy a suitable choice as a construction material for thermal nuclear reactors and nuclear power plants. Other uses are as an ingredient of explosive mixtures, as getter in vacuum tubes, and in making flash bulb, flash powder (historical), and lamp filaments, in rayon spinnerets, and in surgical appliances. 

The extent of oxidation of columbium after 20 hours in air, for several temperatures, was reported by the Fansteel Metallurgical Corporation (33). Columbium starts to oxidize in air at about 200°C. The oxide is said to be adherent and to prevent further oxidation unless the temperature is raised. Columbium is reported not to become brittle on heating in air for short periods, as tantalum does, because the oxide film prevents further reaction. The columbium oxides dissolve into the metal when heated in a vacuum at temperatures between red heat and 1200°C. Above 1200°C. the oxides are reported to evaporate. Columbium, in the oxide free state, is an active getter in vacuum tubes. 

Use Photoelectric cells, getter in vacuum tubes, hydrogenation catalyst, ion propulsion systems, plasma for thermoelectric conversion, atomic clocks, rocket propellant, heat-transfer fluid in power generators, thermochemical reactions, seeding combustion gases for magnetohydrodynamic generators. 

Use Control rods in water-cooled nuclear reactors lightbulb filaments, electrodes, special glasses, getter in vacuum tubes. 

Use Getter in vacuum tubes, research in electrochemistry, spectroscopy. 

Use Lighter flints, ferrous and nonferrous alloys, cast iron, aluminum, nickel, magnesium and copper alloys, getter in vacuum tubes, magnetic alloys. 

Use Coating nuclear fuel rods, corrosion-resistant alloys, photo flashbulbs (foil), pyrotechnics, metal-to-glass seals, special welding fluxes, getter in vacuum tubes, explosive primers, acid manufacturing plants, deoxidizer and scavenger in steel manufacturing, laboratory crucibles, spinnerettes. 

USE In manuf of alloys, especially lithium-hardened bearing metals as a getter" in vacuum tubes. In making catalysts for the polyolefin plastics industry, in fuels for aircraft and missiles. Lithium salts are used in porcelain enamels, in air-conditioning, and for making multi-purpose greases. Human Toxicity Li ion may injure kidneys, especially if sodium intake is limited. 

EINECS 231-169-0 Holmium, Metallic element getter in vacuum tubes, research in electrochemistry, spectroscopy, Meta mp = 1474° bp = 2700°, Atomargic Chemetats Cerac Noah Chem.i Rhone-Poulenc. 

Properties Cryst. solid, metallic luster sol. in dil. acids reacts slowly with water at.wt. 164.9303 dens. 8.803 vapor pressure 2 mm (1630 C) m.p. 1470 C b.p. 2720 C magnetic and elec, props. Precaution Can react violently with air or halogens oxidizes rapidly in moist air Uses Getter in vacuum tubes, research in electrochemistry, spectroscopy Manuf./Distrib. Aldrich http //www.sigma-aldrich.com] Atomergic Chemetals http //www.atomergic.com] Auer-Remy Cerac http //www.cerac.com] Fluka http //www.sigma-aldrich.com... 

Zirconium and its alloys are nontoxic and compatible with bodily fluids and thus are used in making surgical implants and prosthetic devices. The high oxygen affinity of the divided metal powder allow zirconium to be used as a getter in vacuum tubes or in photoflash bulbs or explosive primers. On the other hand, it is used as an alloying agent in steel. Other applications include the manufacture of rayon spinnerets and lamp filaments. 

Although there are few data, it is expected that oxygen-containing gases, such as SO2, and NO2, react with tantalum at some elevated temperature. With hydrocarbons such as benzene or naphthalene, tantalum reacts at temperatures between 1700 and 2500°C to form tantalum carbide. Tantalum has been used as a getter in vacuum tubes to absorb residual gases at temperatures of 650-1000 C. 

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