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Beryllium Ores. mineral formations that contain beryllium in quantities such that its extraction is feasible at modern technical and economic levels. Beryllium is found in the ores mainly in the form of the minerals themselves, as well as in the form of an isomorphic impurity (usually not more than 5–10 percent) in rock-forming minerals. The ...
Beryllium ores and concentrates 2617.90.0030 Free. Beryllium oxide and hydroxide 2825.90.1000 3.7% ad val. Beryllium-copper master alloy 7405.00.6030 Free. Beryllium-copper plates, sheets, and strip: Thickness of 5 millimeters (mm) or more 7409.90.1030 3.0% ad val. Thickness of less than 5 mm:
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased. Beryllium (Be) a chemical element of Group II of Mendeleev's periodic system. Its atomic number is 4; its atomic mass is 9.01218. It is a light metal of lightgray color, and it has one stable isotope, 9Be. Beryllium was discovered in 1798 ...
Beryllium oxide (BeO) is a white crystalline oxide. It occurs in nature as the mineral "Bromellite". Historically, beryllium oxide was called glucina or glucinium oxide. It is an electrical insulator and its thermal conductivity is such that it is higher than any other nonmetal except diamond, and actually exceeds that of some metals.
Although beryllium ore is relatively nontoxic, all other commercially important beryllium compounds exhibit significant pulmonary toxicity (ATSDR, 1988). Individuals employed in beryllium manufacturing, fabricating, or reclaiming industries are at highest risk for exposure and may encounter dusts and fumes of many different beryllium compounds.
Definition. A pneumoconiosis, characterized by granulomatous inflammation, that occurs in individuals who develop beryllium sensitization (BeS), a cell -mediated immune response to environmental and occupational beryllium exposure. BeS precedes the lung disease that may present with chronic dry cough, fatigue, weight loss, chest pain, and ...
Beryllium: A toxic metal found in ores containing other elements that is used in making metal alloys for nuclear reactors and the aerospace industry. Acute exposure to beryllium fumes can cause a severe, sometimes fatal pneumonitis (inflammation of the lungs).Chronic overexposure to beryllium is more common and causes a diffuse inflammatory reaction in the lungs resulting in …
Before this study began, we knew that people exposed to beryllium may develop two forms of beryllium disease, acute and chronic. These are lung diseases caused by exposure to beryllium. The acute form is a rare pneumonia-like disease that occurs shortly after very high exposures to beryllium.
Beryllium ores are first converted to beryllium oxide (BeO) or beryllium hydroxide (Be(OH) 2 ). These compounds are then converted to beryllium chloride (BeCl 2 ) or beryllium fluoride (BeF 2 ). Finally, the pure metal is isolated by: (1) an electric current: or, (2) reaction with …
The element beryllium is a grey metal that is stronger than steel and lighter than aluminum. Its physical properties of great strength-to-weight, high melting point, excellent thermal stability and conductivity, reflectivity, and transparency to X-rays make it an essential material in the aerospace, telecommunications, information technology, defense, medical, and nuclear industries.
Define beryllium bronze. beryllium bronze synonyms, beryllium bronze pronunciation, beryllium bronze translation, English dictionary definition of beryllium bronze. Noun 1. beryllium bronze - a copper-base alloy containing beryllium bronze - an alloy of copper and tin and sometimes other elements; also any copper-base...
Beryllium is a hard, grayish metal naturally found in mineral rocks, coal, soil, and volcanic dust. Beryllium compounds are commercially mined, and the Beryllium is purified for use in nuclear weapons and reactors, aircraft and space vehicle structures, instruments, x-ray machines, and mirrors. Beryllium ores are used to make speciality ceramics for electrical and high-technology applications.
Beryllium is extracted from two types of ores; beryl (Be 3 Al 2 (SiO 3) 6) and bertrandite (Be 4 Si 2 O 7 (OH) 2). While Beryl generally has a higher beryllium content (three to five percent by weight), it is more difficult to refine than bertrandite, which on average contains less than 1.5 percent beryllium.
Beryllium is in wide use in the energy field to extract oil and gas, and has a big role in helping to find tomorrow's clean and affordable energy sources. Transportation. Beryllium alloys are used in automobile components and airplane equipment to ensure the reliable operation of …
Beryllium ores and concentrates 2617.90.0030 Free. Beryllium oxide and hydroxide 2825.90.1000 3.7% ad val. Beryllium-copper master alloy 7405.00.6030 Free. Beryllium-copper plates, sheets, and strip: Thickness of 5 millimeters (mm) or more 7409.90.1030 3.0% …
Beryllium definition, a steel-gray, bivalent, hard, light, metallic element, the salts of which are sweet: used chiefly in copper alloys for better fatigue endurance ...
Extracted from the mineral beryl, bertrandite and phenakite ores, Beryllium exhibits both metallic and non-metallic properties. The element was discovered by Nicolas Louis Vauquelin in 1798 while examining an emerald in beryl form but was not isolated until 1828.
Beryllium Used in the nuclear industry and to make light, very strong alloys used in the aircraft industry. Beryllium salts are used in fluorescent lamps, in X-ray tubes and as a deoxidizer in bronze metallurgy. Beryl is the gem stones emerald and aquamarine. It is used in computers, telecommunication products, aerospace and defense
Beryllium, chemical element that is the lightest member of the alkaline-earth metals of Group 2 of the periodic table. It is used in metallurgy as a hardening agent and in many outer space and nuclear applications. It is a steel-gray metal that is quite brittle at room temperature.
Beryllium plays an indispensable role in modern society. Why beryllium is so unique among metals? First discovered more than two centuries ago, beryllium is a naturally occurring metallic element found in rocks, coal and oil, even the soil in your backyard. Beryllium ore. Beryllium was not widely used in industry until the 1940s and 1950s.
Beryllium is primarily produced using bertrandite and beryl ores. However, 90% of the current production is derived from bertrandite ore. The rising demand for the metal is anticipated to compel ore mining companies to invest in new sites. However, depleting raw material resources are estimated to be a key concern for the industry.
Beryllium Ores | Article about Beryllium Ores by The Free ... The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased. Beryllium Ores mineral formations that contain beryllium in quantities such that its extraction is feasible at modern technical and economic levels.
Beryl definition, a mineral, beryllium aluminum silicate, Be3Al2Si6O18, usually green, but also blue, rose, white, and golden, and both opaque and transparent, the latter variety including the gems emerald and aquamarine: the principal ore of beryllium. See more.
Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit. Ore is extracted from the earth through mining and treated or refined, often via smelting, to extract the valuable metals or minerals. The grade of ore refers to the concentration of the desired material it contains.
Beryllium hydroxide, Be (OH) 2, is an amphoteric hydroxide, dissolving in both acids and alkalis. Industrially it is produced as a by-product in the extraction of beryllium metal from the ores, "beryl" and "bertrandite" When alkali is added to beryllium salt solutions, the α-form (a gel) is formed.
Beryllium oxide definition is - a white amorphous compound BeO having high thermal conductivity and high electrical resistance that is usually obtained by treatment of beryl ore and is used chiefly as a high-temperature refractory (as in crucibles) and in phosphors (as for television screens, X-ray equipment, and formerly fluorescent lamps).
1910.1024 (j) (1) (i) The employer must maintain all surfaces in beryllium work areas and regulated areas as free as practicable of beryllium and in accordance with the written exposure control plan required under paragraph (f) (1) and the cleaning methods required under paragraph (j) …
Define Beryllium Contracts. means any and all agreements or other arrangements (however styled) for the purchase, procurement or other acquisition of beryllium, in whatever form, entered into from time to time by any Customer (including, without limitation, Beryl Ore, Copper Beryllium Master Alloy, Vacuum Cast Beryllium Ingot and Vacuum Hot Pressed Beryllium Billet), but only to the extent ...
Berylliosis Definition Berylliosis is lung inflammation caused by inhaling dust or fumes that contain the metallic element beryllium. Found in rocks, coal, soil, and volcanic dust, beryllium is used in the aerospace industry and in many types of manufacturing. Berylliosis occurs in both acute and chronic forms. In some cases, appearance of the disease ...
A third group, serving as controls, was housed in an inhalation chamber without exposure. The bertrandite ore atmosphere in the inhalation chamber contained 210 ug/cu m beryllium, and the beryl ore atmosphere contained 620 ug/cu m. The mortality of the animals exposed to the two ores exceeded that of controls by 25%.
(Beryl Ore, NCI Thesaurus) This alloy emits toxic fumes of beryllium oxides upon heating. (Beryllium-Copper Alloy, NCI Thesaurus) A crystalline, inorganic compound composed of beryllium and aluminum in which beryllium increases the alloys thermal and electrical conductivity and emits toxic fumes of beryllium oxides upon heating.
Berylliosis is a form of metal poisoning caused by inhalation of beryllium dusts, vapors, or its compounds or implantation of the substance in the skin. The toxic effects of beryllium most commonly occur due to occupational exposure. Beryllium is a metallic element used in many industries, including electronics, high-technology ceramics, metals ...
Beryllium is a silvery-white metal. It is relatively soft and has a low density. Uses. Beryllium is used in alloys with copper or nickel to make gyroscopes, springs, electrical contacts, spot-welding electrodes and non-sparking tools. Mixing beryllium with these metals increases their electrical and thermal conductivity.
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