Boron
Boron in its combined form of borax (Na2B4O7. 10H2O) has been used since early times. Early uses were as a mild antiseptic and cleaner because of its detergent and water-softening properties. Later it was used as a soldering flux and ceramic flux because of its ability to dissolve metal oxides. Borax is used to produce a heat-resistant borosilicate glass for the home and laboratory, familiar to many by the trade mark "Pyrex", and is the starting material for the preparation of other boron compounds. B Boron acid, is mildly antiseptic, is used widely as an eye washer and as a neutron absorver in the swimming-pool type nuclear reactors and in electroplating baths, such as those used for nickel deposition. Its anhydride is used as a source of boron in the fused salt electrolysis method for the preparation of elemental boron.
The boron trifluoride is a gas produced in large quantities for gas tube neutron radiation detectors for monitoring radiation levels in the earth's atmosphere and in space. Some organizations use these devices to ascertain the best underground level at which to blast to produce oil wells of high yield. Boron triflouride is an important industrial catalyst for many organic reactions, such as polymerization reactions. It has also a major role in the electroplating of nickel, lead and tin.
Aluminum boride (AlB12), has been used as a substitute for diamond dust for grinding and polishing. Boron carbide is also used with this purpose and it has found extensive use as a polishing agent, for sandblast nozzles, etc.
Elemental boron is hard and brittle like glass, having similar uses. Boron can be added to pure metals, alloys or to other solids to improve its strength.
Aluminum
The oxide quickly formed in surface of the pure metal turns it ideal for a lot of decoration applications. Because it has high electrical conductivity, ductility and low atomic mass, it is frequently used in electrical transmission lines. The metal has also been used in the coating of telescope mirrors, as well as in the production of aluminum foils, used in the packing of victuals. In the pure form, the metal has a small mechanical resistance, being therefore generally used in alloys with copper, manganese, silicon, magnesium and zinc, with a wide range of mechanical properties. These alloys are used in construction, airplane and automobile structures, traffic signs, heat dissipatives, storage deposits, bridges and kitchen utensils.
Gallium
When gallium first became available in the metallic form, it seemed to have properties not found in any other material. It is relatively inert, nontoxic, and with a melting point only slightly above room temperature and a boiling point of 2403 ºC. It was considered as a liquid sealant in high-vacuum systems, as a heat-transfer medium in high-temperature engines, such as nuclear reactors, and as a component of dental alloys.
It is somewhat paradoxical that the rather substantial uses of gallium that eventually evolved were based not on the unique physical properties of the metal but on the specific chemistry of some of its compounds. The first significant use of gallium was in the spectroscopic analysis of uranium oxide done in operations of the Atomic Energy Commission.
The application of gallium that has received the most attention is the production of semiconducting compounds. For many years, this technology was dominated by the elemental semiconductors, silicon and germanium. But in 1952, German workers reported the achievement of semiconduction in compounds between elements in group III and group V. Of these, the most important are the compounds of gallium with antimony, arsenic or phosporus. Nowadays gallium arsenide (Ga-As) is undoubtedly the most used. This compound is used in the production of several electronic parts such as diodes and transistors, made for voltage rectification, signal amplification, etc. Other gallium arsenide applications are the semiconductor "lasing" and microwave generation and also in several sensors to measure temperature, light or magnetic field.
Indium
The major application of indium is in automobile bearings to improve moisture resistance and antiseizure properties. It is also used in the semiconductor industry. In this application, indium acts as a doping agent in the formation of p-type germanium. Examples are transistors, diodes and rectifiers. T The most important indium alloys are indium-tin, lead-indium-silver and copper-silver-indium, all used as solders. I Indium is also used in plating applications due to its electrolytic properties, and in the production of electroluminescent panels, as an oxide.
Thallium
Thallium and its compounds have very little applications, being normally limited to commercial insecticides and rat poison. Thallium sulfate is an insipid and scentless compound, and is usually added to glycerin, sugar or water to eliminate small rodents and bugs. Thallium applications as a metallic alloy are also limited. The only important alloy is thallium-lead that is used in electric fuses. Thallium is also used as an addictive in special glasses, used in semiconductor protection, capacitors and other electronic devices, to protect them from oxidation and moisture.
Boron Boron in its combined form of borax (Na2B4O7. 10H2O) has been used since early times. Early uses were as a mild antiseptic and cleaner because of its detergent and water-softening properties. Later it was used as a soldering flux and ceramic flux because of its ability to dissolve metal oxides. Borax is used to produce a heat-resistant borosilicate glass for the home and laboratory, familiar to many by the trade mark "Pyrex", and is the starting material for the preparation of other boron compounds. B Boron acid, is mildly antiseptic, is used widely as an eye washer and as a neutron absorver in the swimming-pool type nuclear reactors and in electroplating baths, such as those used for nickel deposition. Its anhydride is used as a source of boron in the fused salt electrolysis method for the preparation of elemental boron. The boron trifluoride is a gas produced in large quantities for gas tube neutron radiation detectors for monitoring radiation levels in the earth's atmosphere and in space. Some organizations use these devices to ascertain the best underground level at which to blast to produce oil wells of high yield. Boron triflouride is an important industrial catalyst for many organic reactions, such as polymerization reactions. It has also a major role in the electroplating of nickel, lead and tin. Aluminum boride (AlB12), has been used as a substitute for diamond dust for grinding and polishing. Boron carbide is also used with this purpose and it has found extensive use as a polishing agent, for sandblast nozzles, etc. Elemental boron is hard and brittle like glass, having similar uses. Boron can be added to pure metals, alloys or to other solids to improve its strength.Aluminum The oxide quickly formed in surface of the pure metal turns it ideal for a lot of decoration applications. Because it has high electrical conductivity, ductility and low atomic mass, it is frequently used in electrical transmission lines. The metal has also been used in the coating of telescope mirrors, as well as in the production of aluminum foils, used in the packing of victuals. In the pure form, the metal has a small mechanical resistance, being therefore generally used in alloys with copper, manganese, silicon, magnesium and zinc, with a wide range of mechanical properties. These alloys are used in construction, airplane and automobile structures, traffic signs, heat dissipatives, storage deposits, bridges and kitchen utensils. Gallium When gallium first became available in the metallic form, it seemed to have properties not found in any other material. It is relatively inert, nontoxic, and with a melting point only slightly above room temperature and a boiling point of 2403 ºC. It was considered as a liquid sealant in high-vacuum systems, as a heat-transfer medium in high-temperature engines, such as nuclear reactors, and as a component of dental alloys. It is somewhat paradoxical that the rather substantial uses of gallium that eventually evolved were based not on the unique physical properties of the metal but on the specific chemistry of some of its compounds. The first significant use of gallium was in the spectroscopic analysis of uranium oxide done in operations of the Atomic Energy Commission. The application of gallium that has received the most attention is the production of semiconducting compounds. For many years, this technology was dominated by the elemental semiconductors, silicon and germanium. But in 1952, German workers reported the achievement of semiconduction in compounds between elements in group III and group V. Of these, the most important are the compounds of gallium with antimony, arsenic or phosporus. Nowadays gallium arsenide (Ga-As) is undoubtedly the most used. This compound is used in the production of several electronic parts such as diodes and transistors, made for voltage rectification, signal amplification, etc. Other gallium arsenide applications are the semiconductor "lasing" and microwave generation and also in several sensors to measure temperature, light or magnetic field.Indium The major application of indium is in automobile bearings to improve moisture resistance and antiseizure properties. It is also used in the semiconductor industry. In this application, indium acts as a doping agent in the formation of p-type germanium. Examples are transistors, diodes and rectifiers. T The most important indium alloys are indium-tin, lead-indium-silver and copper-silver-indium, all used as solders. I Indium is also used in plating applications due to its electrolytic properties, and in the production of electroluminescent panels, as an oxide.Thallium Thallium and its compounds have very little applications, being normally limited to commercial insecticides and rat poison. Thallium sulfate is an insipid and scentless compound, and is usually added to glycerin, sugar or water to eliminate small rodents and bugs. Thallium applications as a metallic alloy are also limited. The only important alloy is thallium-lead that is used in electric fuses. Thallium is also used as an addictive in special glasses, used in semiconductor protection, capacitors and other electronic devices, to protect them from oxidation and moisture.
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