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12 novembre 2011 6 12 /11 /novembre /2011 03:28

Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium includeberyl (aquamarine, emerald) and chrysoberyl. As a free element it is a steel-gray, strong, lightweight and brittle alkaline earth metal.Sony VAIO VGN-Z620D Battery

Beryllium is used primarily as a hardening agent in alloys, notably beryllium copper. In structural applications, highflexural rigidity, thermal stability, thermal conductivity and low density (1.85 times that of water) make beryllium a quality aerospace material for high-speed aircraft, missiles, space vehicles and communication satellites. Sony VAIO VGN-Z620N/B Battery

Because of its low density and atomic mass, beryllium is relatively transparent to X-rays and other forms of ionizing radiation; therefore, it is the most common window material for X-ray equipment and in particle physics experiments. The high thermal conductivity of beryllium and beryllium oxide have led to their use in heat transport and heat sinking applications.Sony VAIO VGN-Z650N/B Battery

The commercial use of beryllium metal presents technical challenges due to the toxicity (especially by inhalation) of beryllium-containing dusts. Beryllium is corrosive to tissue, and can cause a chronic life-threatening allergic disease called berylliosis in some people.Sony VAIO VGN-Z670N/B Battery

As it is not synthesized in stars, beryllium is a relatively rare element in both the Earth and the universe. The element is not known to be necessary or useful for either plant or animal life.

Physical properties

Beryllium has exceptional flexural rigidity (Young's modulus 287 GPa) and a reasonably high melting point.Sony VAIO VGN-Z690CTO Battery

The modulus of elasticity of beryllium is approximately 50% greater than that of steel. The combination of this modulus and a relatively low density results in an unusually fast sound conduction speed in beryllium – about 12.9 km/s at ambient conditions.Sony VAIO VGN-Z690NAX Battery

Other significant properties are high specific heat (1925 J·kg?1·K?1) and thermal conductivity (216 W·m?1·K?1), which make beryllium the metal with the best heat dissipation characteristics per unit weight. In combination with the relatively low coefficient of linear thermal expansion (11.4×10?6 K?1), these characteristics result in a unique stability under conditions of thermal loading.Sony VAIO VGN-Z690PAB Battery

Nuclear properties

Beryllium has a large scattering cross section for high-energy neutrons, about 6 barns for energies above ~0.01 eV. Therefore, it effectively slows the neutrons to the thermal energy range of below 0.03 eV, where the total cross section is at least an order of magnitude lower – exact value strongly depends on the purity and size of the crystallites in the material. Sony VAIO VGN-Z690PCB Battery

The predominant beryllium isotope 9Be also undergoes a (n,2n) neutron reaction to 8Be, which then instantaneously breaks into two alpha particles; that is, beryllium is a neutron multiplier, releasing more neutrons than it absorbs. This nuclear reaction is:Sony VAIO VGN-Z690PDB Battery

As a metal, beryllium is transparent to most wavelengths of X-rays and gamma rays, making it useful for the output windows ofX-ray tubes and other such apparatus. It is also a good source for the relatively-small numbers of free neutrons in the laboratory which are liberated when beryllium nuclei are struck by energetic alpha particles producing the nuclear reaction ?Sony VAIO VGN-Z690PEB Battery

Isotopes and nucleosynthesis

Beryllium contains only one stable isotope, 9Be, and therefore is a monoisotopic element. Cosmogenic 10Be is produced in theatmosphere of the Earth by the cosmic ray spallation of oxygen and nitrogen. Sony VAIO VGN-Z690PFB Battery

Cosmogenic 10Be accumulates at the soil surface, where its relatively long half-life (1.36 million years) permits a long residence time before decaying to boron-10. Thus, 10Be and its daughter products are used to examine natural soil erosion, soil formation and the development of lateritic soils, and as a proxy for measurement of the variations in solar activity and the age of ice cores.Sony VAIO VGN-Z690YAD Battery

The production of 10Be is inversely proportional to the solar activity, because the increased solar wind during periods of high solar magnetic activity in turn decreases the flux of galactic cosmic rays that reach the Earth. Nuclear explosions also form 10Be by the reaction of fast neutrons with 13C in the carbon dioxide in air. Sony VAIO VGN-Z691Y/B Battery

This is one of the indicators of past activity at nuclear weapon test sites.

The isotope 7Be (half-life 53 days) is also cosmogenic, and shows an atmospheric abundance linked to sunspots much like 10Be.Sony VAIO VGN-Z691Y/X Battery

8Be has a very short half-life of about 7×10?17 s that contributes to its significant cosmological role, as elements heavier than beryllium could not have been produced by nuclear fusion in the Big Bang. This is due to the lack of sufficient time during the Big Bang's nucleosynthesis phase to produce carbon by the fusion of 4He nuclei and the very low concentrations of available beryllium-8. Sony VAIO VGN-Z698Y/X Battery

The British astronomer Sir Fred Hoyle first showed that the energy levels of 8Be and 12C allow carbon production by the so-called triple-alpha process in helium-fueled stars where more nucleosynthesis time is available, thus making creation of carbon-based life possible from the gas and dust ejected by supernovas (see also Big Bang nucleosynthesis).Sony VAIO VGN-Z70B Battery

The innermost electrons of beryllium may contribute to chemical bonding. Therefore, when 7Be decays by electron capture, it does so by taking electrons from atomic orbitals that may participate in bonding. This makes its decay rate dependent to a measurable degree upon its electron configuration – a rare occurrence in nuclear decay.Sony VAIO VGN-Z699JAB Battery

The shortest-lived known isotope of beryllium is 13Be which decays through neutron emission. It has a half-life of 2.7 × 10?21 s. 6Be is also very short-lived with a half-life of 5.0 × 10?21 s. The exotic isotopes 11Be and 14Be are known to exhibit a nuclear halo.Sony VAIO VGN-Z71JB Battery

This phenomenon can be understood as the nuclei of 11Be and 14Be have, respectively, 1 and 4 neutrons orbiting substantially outside the classical Fermi 'waterdrop' model of the nucleus.

Unstable isotopes of beryllium are created in stars, but these do not last long. It is believed that most of the stable beryllium was created when cosmic rays induced fission in heavier elements found in interstellar gas and dust.Sony VAIO VGN-Z73FB Battery

Occurrence

Beryllium is scarce in the universe. With a concentration of 1 part per billion (ppb) by weight, it is much less abundant than all elements preceding niobium, with the exception of boron, which has a similar abundance. Beryllium is similarly rare in the Sun with a concentration of 0.1 ppb by weight, similar to that of rhenium.Sony VAIO VGN-Z790DKX Battery

The beryllium concentration in the Earth's surface rocks is ca. 4–6 ppm by atoms. Beryllium is a major constituent of about 100 out of some 4000 known minerals, the most important of which are bertrandite (Be4Si2O7(OH)2), beryl (Al2Be3Si6O18),chrysoberyl (Al2BeO4) and phenakite (Be2SiO4). Precious forms of beryl are aquamarine, bixbite and emerald.Sony VAIO VGN-Z790DMR Battery

In sea water, beryllium is exceedingly rare, more so than even scandium, comprising only 0.0006 ppb by weight.In stream water, however, beryllium is more abundant with 0.1 ppb by weight.

Production

Because of its high affinity for oxygen at elevated temperatures, and its ability to reduce water when its oxide film is removed, the extraction of beryllium from its compounds is a difficult process. Sony VAIO VGN-Z790DND Battery

Electrolysis of a mixture of beryllium fluoride and sodium fluoride was used to isolate beryllium during the 19th century. The metal's high melting point makes this process more energy-consuming than corresponding processes used for the alkali metals. Sony VAIO VGN-Z820DB Battery

Early in the 20th century, the production of beryllium by the thermal decomposition of beryllium iodide was investigated following the success of a similar process for the production of zirconium, but this process proved to be uneconomical for volume production.Sony VAIO VGN-Z820G/B Battery

Pure beryllium metal did not become readily available until 1957, even though it had been used as an alloying metal to harden and toughen copper much earlier. Beryllium could be produced by reducing beryllium compounds such as beryllium chloride with metallic potassium or sodium. Sony VAIO VGN-Z890GLX Battery

Currently most beryllium is produced by reducing beryllium fluoride with purified magnesium. The price on the American market for vacuum-cast beryllium ingots was about $338 per pound ($745 per kilogram) in 2001. The chemical equation for the key reaction is as follows:Sony VAIO VGN-Z890GMR Battery

The United States, China and Kazakhstan are the only three countries involved in the industrial scale extraction of beryllium. In the US,Brush Wellman Inc. is the main producer of beryllium and beryllium products. This company smelts its beryllium ore, which contains the mineral bertrandite, and which comes mostly from the company-owned Spor Mountain deposit in the State of Utah.Sony VAIO VGN-Z898H/X Battery

The smelting and other refining of the beryllium is carried out at a factory 10 miles north of Delta, Utah, a location chosen for its remoteness and proximity to theIntermountain Power Project. Between 1998 and 2008, the world's production of beryllium had decreased from 343 to about 200 tonnes, of which 176 tonnes (88%) came from the United States.Sony VAIO VGN-Z90FS Battery

Chemical properties

Beryllium metal is located above aluminium in the electrochemical series and therefore is expected to show significant chemical activity; however, it is passivated by an oxide layer and does not react with air or water even at red heat.Sony VAIO VGN-Z90NS Battery

Once ignited, beryllium burns brilliantly forming a mixture ofberyllium oxide and beryllium nitride. Beryllium dissolves readily in non-oxidizing acids, such as HCl and diluted H2SO4, but not in nitric acid as this forms the oxide. This behavior is similar to that of aluminium metal. Sony VAIO VGN-Z90PS Battery

Beryllium, again similarly to aluminium, dissolves in warm alkali solutions to form the beryllate anion, Be(OH)42?, and hydrogen gas.

The beryllium atom has the electronic configuration [He] 2s2. In beryllium compounds the two electrons are lost and beryllium is in the +2 oxidation state; the only evidence of lower valence of beryllium is in the solubility of the metal in BeCl2.Sony VAIO VGN-Z90S Battery

The small atomic radius leads to significant covalent character in beryllium's bonding. Beryllium is 4-fold coordinated in virtually all of its derivatives, e.g. [Be(H2O)4]2+ and tetrahaloberyllates, BeX42?. This characteristic is employed in analytical techniques using EDTA as a ligand. Sony VAIO VGN-Z90US Battery

EDTA preferentially forms octahedral complexes – thus absorbing other cations such as Al3+which might interfere – for example, in the solvent extraction of a complex formed between Be2+ and acetylacetone.

Solutions of beryllium salts, e.g. beryllium sulfate and beryllium nitrate, are acidic because of hydrolysis of the [Be(H2O)4]2+ion.

[Be(H2O)4]2+ + H2O   [Be(H2O)3(OH)]+ + H3O+   Sony VAIO VGN-Z91DS Battery

Other products of hydrolysis include the trimeric ion [Be3(OH)3(H2O)6]3+. Beryllium hydroxide, Be(OH)2, is insoluble even in acidic solutions with pH less than 6, that is at biological pH. It is amphoteric and dissolves in strongly alkaline solutions.Sony VAIO VGN-Z91JS Battery

Beryllium forms binary compounds with many non-metals. Anhydrous halides are known for F, Cl, Br and I. BeF2 has a silica-like structure with corner-shared BeF4 tetrahedra. BeCl2 and BeBr2 have chain structures with edge-shared tetrahedra. All beryllium halides have a linear monomeric molecular structure in the gas phase.Sony VAIO VGN-Z91PS Battery

Beryllium oxide, BeO, is a white refractory solid, which has the wurtzite crystal structure and a thermal conductivity as high as in some metals. BeO is amphoteric. Salts of beryllium can be produced by treating Be(OH)2 with acid.[27] Beryllium sulfide, selenide and telluride are known, all having the zincblende structure.Sony VAIO VGN-Z91YS Battery

Beryllium nitride, Be3N2 is a high-melting-point compound which is readily hydrolyzed. Beryllium azide, BeN6 is known and beryllium phosphide, Be3P2 has a similar structure to Be3N2. Basic beryllium nitrate and basic beryllium acetate have similar tetrahedral structures with four beryllium atoms coordinated to a central oxide ion.Sony VAIO VGN-Z92DS Battery

A number of beryllium borides are known, such as Be5B, Be4B, Be2B, BeB2, BeB6 and BeB12. Beryllium carbide, Be2C, is a refractory brick-red compound that reacts with water to give methane. No beryllium silicide has been identified.

History

Early analyses of emeralds and beryls always yielded similar elements, leading to the fallacious conclusion that both substances are aluminium silicates.Sony VAIO VGN-Z92JS Battery

René Just Haüy discovered that both crystals show strong similarities, and he asked the chemist Louis-Nicolas Vauquelin for a chemical analysis. Vauquelin was able to separate the aluminium from the beryllium by dissolving the aluminium hydroxide in an additional alkali.Vauquelin named the new element "glucinum" for the sweet taste of some of its compounds.Sony VAIO VGN-Z92PS Battery

Friedrich Wöhler and Antoine Bussy independently isolated beryllium in 1828 by the chemical reaction of metallic potassium with beryllium chloride, as follows:

BeCl2 + 2 K ? 2 KCl + Be

The potassium itself had been produced by the electrolysis of its compounds, a newly discovered process. Sony VAIO VGN-Z92YS Battery

This chemical method yielded only small grains of beryllium from which no ingot of metal could be cast or hammered. The direct electrolysis of a molten mixture of beryllium fluoride and sodium fluoride by Paul Lebeau in 1898 resulted in the first pure samples of beryllium.Sony VAIO VGN-Z93FS Battery

It took until World War I (1914–18) before significant amounts of beryllium were produced, but large-scale production was not started until early 1930s. It saw a rapid increase during World War II, due to the rising demand for hard beryllium-copper alloys and phosphorsfor fluorescent lights. Sony VAIO VGN-Z93GS Battery

In the first years, most fluorescent lamps used zinc orthosilicate with varying content of beryllium to emit greenish light. Small additions of magnesium tungstate improved the blue part of the spectrum yielding acceptable white. After it was discovered that beryllium was toxic, halophosphate-based phosphors took over.Sony VAIO VGN-Z93HS Battery

Etymology

Early usage of the word beryllium can be traced to many languages, including Latin Beryllus; French Béry; Greek ????????, b?rullos, beryl; Prakrit veruliya(????????); P?li ve?uriya (???????), ve?iru (??????) or vi?ar (?????) – "to become pale," in reference to the pale semiprecious gemstone beryl. Sony VAIO VGN-Z93VS Battery

The original source is probably the Sanskrit word ??????? vaidurya-, which is of Dravidian origin and could be derived from the name of the modern city of Belur. For about 160 years, beryllium was also known as glucinum or glucinium (with the accompanying chemical symbol "Gl", ), the name coming from the Greek word for sweet: ??????, due to the sweet taste of beryllium salts.Sony VAIO VGN-AW92YS Battery

Applications

It is estimated that most beryllium is used for military applications, so information is not readily available.

Radiation windows

Because of its low atomic number and very low absorption for X-rays, the oldest and still one of the most important applications of beryllium is in radiation windows for X-ray tubes.Sony VAIO VGN-AW93FS Battery

Extreme demands are placed on purity and cleanliness of beryllium to avoid artifacts in the X-ray images. Thin beryllium foils are used as radiation windows for X-ray detectors, and the extremely low absorption minimizes the heating effects caused by high intensity, low energy X-rays typical of synchrotron radiation.Sony VAIO VGN-AW93GS Battery

Vacuum-tight windows and beam-tubes for radiation experiments on synchrotrons are manufactured exclusively from beryllium. In scientific setups for various X-ray emission studies (e.g., energy-dispersive X-ray spectroscopy) the sample holder is usually made of beryllium because its emitted X-rays have much lower energies (~100 eV) than X-rays from most studied materials.Sony VAIO VGN-AW93HS Battery

Low atomic number also makes beryllium relatively transparent to energetic particles. Therefore it is used to build the beam pipe around the collision region in particle physicssetups, such as all four main detector experiments at the Large Hadron Collider (ALICE, ATLAS, CMS, LHCb), the Tevatron and the SLAC. Sony VAIO VGN-AW93ZFS Battery

The low density of beryllium allows collision products to reach the surrounding detectors without significant interaction, its stiffness allows a powerful vacuum to be produced within the pipe to minimize interaction with gases, its thermal stability allows it to function correctly at temperatures of only a few degrees above absolute zero, and its diamagnetic nature keeps it from interfering with the complex multipole magnet systems used to steer and focus the particle beams. Sony VAIO VGN-AW93ZGS Battery

Mechanical applications

Because of its stiffness, light weight and dimensional stability over a wide temperature range, beryllium metal is used for lightweight structural components in the defense and aerospace industries in high-speed aircraft, missiles, space vehicles and communication satellites. Sony VAIO VGN-AW93ZHS Battery

Several liquid-fuel rockets use nozzles of pure beryllium. A small number of bicycle frames were built with beryllium, at "astonishing" prices.

Beryllium is used as an alloying agent in the production of beryllium copper, which contains up to 2.5% beryllium. Sony VAIO VGN-BZ11EN Battery

Beryllium-copper alloys are used in many applications because of their combination of high electrical and thermal conductivity, high strength and hardness, nonmagnetic properties, along with good corrosionand fatigue resistance. These applications include the making of spot welding electrodes, springs, non-sparking tools and electrical contacts.Sony VAIO VGN-BZ11MN Battery

The excellent elastic rigidity of beryllium has led to its extensive use in precision instrumentation, e.g. in gyroscope inertial guidance systems and in support structures for optical systems. Beryllium-copper alloys were also applied as a hardening agent in Jason pistols, which were used to strip paint from the hulls of ships.Sony VAIO VGN-BZ11XN Battery

An earlier major application of beryllium was in brakes for military aircraft because of its hardness, high melting point and exceptional heat dissipation. Environmental considerations have led to substitution by other materials.

To reduce cost, beryllium may be fabricated with large amounts of aluminium, resulting in AlBeMet (trade name). This blend is cheaper, while still retaining many desirable properties.Sony VAIO VGN-BZ12VN Battery

Mirrors

Beryllium mirrors are of particular interest. Large-area mirrors, frequently with a honeycomb support structure, are used, for example, in meteorological satelliteswhere low weight and long-term dimensional stability are critical.Sony VAIO VGN-BZ12XN Battery

Smaller beryllium mirrors are used in optical guidance systems and in fire-control systems, e.g. in the German-made Leopard 1 and Leopard 2 main battle tanks. In these systems, very rapid movement of the mirror is required which again dictates low mass and high rigidity. Sony VAIO VGN-BZ31VT Battery

Usually the beryllium mirror is coated with hard electroless nickel plating which can be more easily polished to a finer optical finish than beryllium. In some applications, though, the beryllium blank is polished without any coating. This is particularly applicable to cryogenic operation where thermal expansion mismatch can cause the coating to buckle.Sony VAIO VGN-BZ31XT Battery

The James Webb Space Telescope[44] will have 18 hexagonal beryllium sections for its mirrors. Because JWST will face a temperature of 33 K, the mirror is made of beryllium, capable of handling extreme cold better than glass. Beryllium contracts and deforms less than glass – and remains more uniform – in such temperatures.Sony VAIO VGN-BZ560 Battery

For the same reason, the optics of the Spitzer Space Telescope are entirely built of beryllium metal.

Magnetic applications

Beryllium is non-magnetic. Therefore, tools fabricated out of beryllium are used by naval or military explosive ordnance disposal teams for work on or near naval mines, since these mines commonly have magnetic fuzes.Sony VAIO VGN-BZ560N24 Battery

They are also found in maintenance and construction materials near magnetic resonance imaging (MRI) machines because of the high magnetic fields generated by them. In the fields of radio communications and powerful (usually military) radars, hand tools made of beryllium are used to tune the highly magnetic klystrons,Sony VAIO VGN-BZ560N30 Battery

magnetrons, traveling wave tubes, etc., that are used for generating high levels of microwave power in thetransmitters.

Nuclear applications

Thin plates or foils of beryllium are sometimes used in nuclear weapon designs as the very outer layer of the plutonium pits in the primary stages of thermonuclear bombs, placed to surround the fissile material. Sony VAIO VGN-BZ560P Battery

These layers of beryllium are good "pushers" for the implosion of the plutonium-239, and they are also good neutron reflectors, just as they are in beryllium-moderated nuclear reactors.

Beryllium is also commonly used as a neutron source in laboratory experiments in which relatively few neutrons are needed (rather than having to use a nuclear reactor).Sony VAIO VGN-BZ560P20 Battery

For this purpose, a target of beryllium-9 is bombarded with energetic alpha particles from a radio-isotope such as polonium-210, radium-226, plutonium-239, or americium-241. In the nuclear reaction that occurs, a beryllium nucleus are transmuted into carbon-12, and one free neutron is emitted, traveling in about the same direction as the alpha particle was heading. Sony VAIO VGN-BZ560P22 Battery

Such neutron sources, named "urchin" neutron initiators, were used some in early atomic bombs.

Beryllium is also used at the Joint European Torus nuclear-fusion research laboratory, and it will be used in the more advanced ITER to condition the components which face the plasma.Sony VAIO VGN-BZ560P28 Battery

Beryllium has also been proposed as a cladding material for nuclear fuel rods, owing to its good combination of mechanical, chemical and nuclear properties. Beryllium fluoride is one of the constituent salts of the eutectic salt mixture FLiBe, which is used as a solvent, moderator and coolant in many hypothetical molten salt reactor designs.Sony VAIO VGN-BZ560P30 Battery

Acoustics

Low weight and high rigidity of beryllium make it useful as a material for high-frequency speaker drivers. Because beryllium is expensive (many times more thantitanium), hard to shape due to its brittleness, and toxic if mishandled, beryllium tweeters are limited to high-end home, pro audio and public addressapplications.Sony VAIO VGN-BZ560P34 Battery

More often, beryllium is alloyed with other metals, which is sometimes not disclosed for marketing purposes.

Electronic

Beryllium is a p-type dopant in III-V compound semiconductors. It is widely used in materials such as GaAs, AlGaAs, InGaAs and InAlAs grown by molecular beam epitaxy(MBE).Sony VAIO VGN-BZ561 Battery

Cross-rolled beryllium sheet is an excellent structural support for printed circuit boards in surface-mount technology. In critical electronic applications, beryllium is both a structural support and heat sink. The application also requires a coefficient of thermal expansion that is well matched to thealumina and polyimide-glass substrates. Sony VAIO VGN-BZ561N20 Battery

The beryllium-beryllium oxide composite "E-Materials" have been specially designed for these electronic applications and have the additional advantage that the thermal expansion coefficient can be tailored to match diverse substrate materials.

Beryllium oxide is useful for many applications that require the combined properties of an electrical insulator and an excellent heat conductor, with high strength and hardness, and a very high melting point.Sony VAIO VGN-BZ561P20 Battery

Beryllium oxide is frequently used as an insulator base plate in high-power transistors in radio frequency transmittersfor telecommunications. Beryllium oxide is also being studied for use in increasing the thermal conductivity of uranium dioxide nuclear fuel pellets.Sony VAIO VGN-BZ562P Battery

Beryllium compounds were used in fluorescent lighting tubes, but this use was discontinued because of the disease berylliosis which developed in the workers who were making the tubes.

Complexes

Beryllium(II) readily forms complexes with strong donating ligands such as phosphine oxides and arsine oxides. There have been extensive studies of these complexes which show the stability of the O-Be bond.Sony VAIO VGN-BZ563P Battery

Toxicity

The toxicity of beryllium depends upon the duration, intensity and frequency of exposure (features of dose), as well as the form of beryllium and the route of exposure (e.g., inhalation, dermal, ingestion). According to the International Agency for Research on Cancer (IARC), beryllium and beryllium compounds are Category 1 carcinogens;Sony VAIO VGN-BZAAFS Battery

they are carcinogenic to animals (including humans). Chronic berylliosis is a pulmonary and systemic granulomatous disease caused by exposure to beryllium. Acute beryllium disease in the form of chemical pneumonitis was first reported in Europe in 1933 and in the United States in 1943.Sony VAIO VGN-BZAAHS Battery

Cases of chronic berylliosis were first described in 1946 among workers in plants manufacturing fluorescent lamps in Massachusetts. Chronic berylliosis resembles sarcoidosis in many respects, and the differential diagnosis is often difficult. It killed some early workers in nuclear weapons design, such as Herbert L. Anderson.Sony VAIO VGN-BZAANS Battery

Early researchers tasted beryllium and its various compounds for sweetness in order to verify its presence. Modern diagnostic equipment no longer necessitates this highly risky procedure and no attempt should be made to ingest this highly toxic substance.Sony VAIO VGN-BZAAPS Battery

Beryllium and its compounds should be handled with great care and special precautions must be taken when carrying out any activity which could result in the release of beryllium dust (lung cancer is a possible result of prolonged exposure to beryllium laden dust).Sony VAIO VGN-CR11H/B Battery

Although the use of beryllium compounds in fluorescent lighting tubes was discontinued in 1949, potential for exposure to beryllium exists in the nuclear and aerospace industries and in the refining of beryllium metal and melting of beryllium-containing alloys, the manufacturing of electronic devices, and the handling of other beryllium-containing material.Sony VAIO VGN-CR11S/L Battery

A successful test for beryllium in air and on surfaces has been recently developed and published as an international voluntary consensus standard ASTM D7202. The procedure uses dilute ammonium bifluoride for dissolution and fluorescence detection with beryllium bound to sulfonated hydroxybenzoquinoline, Sony VAIO VGN-CR11S/P Battery

allowing up to 100 times more sensitive detection than the recommended limit for beryllium concentration in the workplace. Fluorescence increases with increasing beryllium concentration. The new procedure has been successfully tested on a variety of surfaces and is effective for the dissolution and ultratrace detection of refractory beryllium oxide and siliceous beryllium (ASTM D7458).Sony VAIO VGN-CR11S/W Battery

Beryllium poisoning refers to the toxic effects of beryllium, in its elemental form or in various chemical compounds. The toxicity of beryllium depends upon the duration, intensity and frequency of exposure (features of dose), as well as the form of beryllium and the route of exposure (i.e. inhalation, dermal, ingestion).Sony VAIO VGN-CR11Z/R Battery

According to the International Agency for Research on Cancer (IARC), beryllium and beryllium compounds are Category 1 carcinogens; they are carcinogenic to both animals and humans.

Chronic berylliosis is a pulmonary and systemic granulomatous disease caused by exposure to beryllium. Sony VAIO VGN-CR120E/L Battery

Acute beryllium disease in the form of chemical pneumonitis was first reported in Europe in 1933 and in the United States in 1943. Cases of chronic berylliosis were first described in 1946 among workers in plants manufacturing fluorescent lamps in Salem, Massachusetts.Sony VAIO VGN-CR120E/P Battery

Chronic berylliosis resembles sarcoidosis in many respects, and the differential diagnosis is often difficult. It occasionally killed early workers in nuclear weapons design, such as Herbert L. Anderson. Sony VAIO VGN-CR120E/R Battery

Although the use of beryllium compounds in fluorescent lighting tubes was discontinued in 1949, potential for exposure to beryllium exists in the nuclear and aerospace industries and in the refining of beryllium metal and melting of beryllium-containing alloys, the manufacturing of electronic devices, and the handling of other beryllium-containing material.Sony VAIO VGN-CR120E/W Battery

Early researchers tasted beryllium and its various compounds for sweetness in order to verify its presence. Modern diagnostic equipment no longer necessitates this highly risky procedure and no attempt should be made to ingest this highly toxic substance.Sony VAIO VGN-CR125E/B Battery

Beryllium and its compounds should be handled with great care and special precautions must be taken when carrying out any activity which could result in the release of beryllium dust (lung cancer is a possible result of prolonged exposure to beryllium laden dust).

This substance can be handled safely if certain procedures are followed.Sony VAIO VGN-CR13/B Battery

No attempt should be made to work with beryllium before familiarization with correct handling procedures.

A successful test for beryllium in air and on surfaces has been recently developed and published as an international voluntary consensus standard (ASTM D7202; www.astm.org). Sony VAIO VGN-CR13/L Battery

The procedure uses dilute ammonium bifluoride for dissolution and fluorescence detection with beryllium bound to sulfonated hydroxybenzoquinoline, allowing detection up to 100 times lower than the recommended limit for beryllium concentration in the workplace.Sony VAIO VGN-CR13/P Battery

Fluorescence increases with increasing beryllium concentration. The new procedure has been successfully tested on a variety of surfaces and is effective for the dissolution and ultratrace detection of refractory beryllium oxide and siliceous beryllium (ASTM D7458).Sony VAIO VGN-CR13/R Battery

Inhalation

Beryllium is harmful if inhaled and the effects depend on the duration, intensity, and frequency of exposure. If beryllium concentrations in air are high enough (greater than 100 µg/m3), an acute condition can result, called acute beryllium disease, which resembles pneumonia. Sony VAIO VGN-CR13/W Battery

Occupational and community air standards are effective in preventing most acute lung damage. Long-term beryllium exposure can increase the risk of developing lung cancer.

The more common serious health problem from beryllium today is chronic beryllium disease (CBD), discussed below.Sony VAIO VGN-CR131E/L Battery

It continues to occur in industries as diverse as metal recycling, dental laboratories, alloy manufacturing, nuclear weapons production and metal machine shops that work with alloys containing small amounts of beryllium. Sony VAIO VGN-CR13G Battery

A 2005 study found that "Both CBD and sensitization occurred in former workers whose mean daily working lifetime average exposures were lower than the current allowable Occupational Safety and Health Administration workplace air level of 2 ?g/m3 and the Department of Energy guideline of 0.2 ?g/m3."Sony VAIO VGN-CR13G/B Battery

A 2008 report from the United States National Research Council said that worker exposure to beryllium should be kept "at the lowest feasible level," as the agency's research could not establish any safe level of exposure.

Acute Beryllium Disease

Overexposure to beryllium can cause inflammation of the upper and/or lower respiratory tracts.Sony VAIO VGN-CR13G/L Battery

The symptoms of acute beryllium disease are non-specific, resembling other inhalational injuries, viral infections, or pneumonia. Upper respiratory findings include nasopharyngitis and tracheobronchitis. Symptoms may include irritation of the nares and pharynx, epistaxis, cough, and a metallic taste.Sony VAIO VGN-CR13G/P Battery

Nasopharyngitis can progress to formation of nasal fissures, ulcerations, or perforation.

Therapy is supportive and includes removal from further beryllium exposure. Acute beryllium pneumonitis produces severe cough (occasionally with blood-streaked sputum), chest pain or burning, and shortness of breath.Sony VAIO VGN-CR13G/R Battery

The patient is usually ill-appearing, and presents with hypoxemia, cyanosis, tachycardia, and shallow rapid breathing. Systemic symptoms include fever (usually low-grade), malaise, and anorexia. The chest X-ray can reveal diffuse, bilateral alveolar infiltrates.Sony VAIO VGN-CR13G/W Battery

There is no specific diagnostic test for acute beryllium disease. Biopsy of the lungs reveals a nonspecific granulomatous inflammation. Treatment is supportive, including oxygen supplementation as needed, and removal from further beryllium exposure. Corticosteroids are sometimes tried, but no good controlled studies are reported.Sony VAIO VGN-CR13T/L Battery

ttery-27918.htm" title="Sony VAIO VGN-CR13T/L laptop battery">The signs and symptoms of acute beryllium pneumonitis usually resolve over several weeks to months, but it may be fatal, and about 15–20% of cases may progress to CBD.

Chronic Beryllium Disease (CBD)

Sensitization is not an illness, but some exposed individuals, if inhaling sufficient quantities of beryllium dust in the micrometer-size range, may have an inflammatory reaction that principally targets the respiratory system and skin. Sony VAIO VGN-CR13T/P Battery

This condition is called chronic beryllium disease (CBD), and can occur within a few months or many years (average 10 years in some series ) after exposure to higher-than-normal levels of beryllium (greater than 0.2 µg/m3). This disease causes fatigue, weakness, night sweats and can cause difficulty in breathing and a persistent dry cough. Sony VAIO VGN-CR13T/R Battery

It can result in anorexia, weight loss, and may also lead to right-side heart enlargement and heart disease in advanced cases.

Typically, CBD has an insidious onset and runs an indolent course. Some people who are sensitized to beryllium may not have symptoms, and just being sensitized is not a recognized health effect. Sony VAIO VGN-CR13T/W Battery

CBD occurs when the body's immune system recognizes beryllium particles as foreign material and mounts an immune system attack against the particles. Because these particles are typically inhaled into the lungs, the lungs become the major site where the immune system responds. Sony VAIO VGN-CR15/B Battery

The lung sacs become inflamed and fill with large numbers of white blood cells that accumulate wherever beryllium particles are found. These cells form balls around the beryllium particles called "granulomas." When enough of these develop, they interfere with the normal function of the organ. Sony VAIO VGN-CR150E/B Battery

Over time, the lungs become stiff and lose their ability to transfer oxygen from the air into the bloodstream. Early on in the disease, there may be a mild obstructive ventilatory defect. In advanced cases, there is a restrictive defect and reduced diffusion capacity. Patients with CBD develop difficulty inhaling and exhaling sufficient amounts of air, and the amount of oxygen in their bloodstreams falls.Sony VAIO VGN-CR190 Battery

Most of the clinical features of CBD are indistinguishable from thoracic involvement with sarcoidosis. The chest radiograph usually reveals bilateral, mid- and upper-lobe predominant reticulonodular infiltrates, as well as hilar and mediastinal adenopathy. For suspected cases of CBD, fiber-optic bronchoscopy withbronchoalveolar lavage (BAL) is indicated. Sony VAIO VGN-CR190E/L Battery

The BAL fluid should undergo beryllium lymphocyte proliferation testing (BAL BeLPT), the "gold standard" for the diagnosis. The measurement of beryllium in urine or tissue does not establish the diagnosis, and there are technical and interpretive problems with these tests. Blood BeLPT detects approximately 70-90% of CBD cases.Sony VAIO VGN-CR190E/P Battery

CBD is treatable, but not curable with traditional drugs and medicine. Removal from further beryllium exposure is advisable. Treatment includes supplemental oxygen and corticosteroids (such as prednisone) to lower the body's overreaction to beryllium. If therapy with corticosteroid is successful, treatment is usually continued lifelong because of disease relapse after steroid cessation.Sony VAIO VGN-CR190E/R Battery

In general, CBD worsens without treatment. Prognosis is best for those diagnosed at an earlier stage. Overall mortality rates are 5-38%.

The general population is unlikely to develop acute or chronic beryllium disease because ambient air levels of beryllium are normally very low (<0.03 ng/m3).Sony VAIO VGN-CR190E/W Battery

Ingestion

Swallowing beryllium has not been reported to cause effects in humans because very little beryllium is absorbed from the stomach and intestines. Harmful effects have sometimes been seen in animals ingesting beryllium.Sony VAIO VGN-CR19VN/B Battery

Dermatological effects

Beryllium can cause local irritation and contact dermatitis. Beryllium contact with skin that has been scraped or cut may cause rashes, ulcers, or bumps under the skin called granulomas.  Beryllium dust or powder can irritate the eyes, producing itching, burning, or conjunctivitis.Sony VAIO VGN-CR19XN/B Battery

Effects on children

There are no studies on the health effects of children exposed to beryllium, although individual cases of CBD have been reported in children of beryllium workers from the 1940s. It is unknown whether children differ from adults in their susceptibility to beryllium. It is unclear whether beryllium is teratogenic.Sony VAIO VGN-CR20 Battery

Detection in the body

Beryllium can be measured in the urine and blood. The amount of beryllium in blood or urine may not indicate time or quantity of exposure. Beryllium levels can also be measured in lung and skin samples. Sony VAIO VGN-CR21/B Battery

While such measurements may help establish that exposure has occurred, other tests are used to determine if that exposure has resulted in health effects. A blood test, the blood beryllium lymphocyte proliferation test (BeLPT), identifies beryllium sensitization and has predictive value for CBD.Sony VAIO VGN-CR21E/L Battery

The BeLPT has become the standard test for detecting beryllium sensitization and CBD in individuals who are suspected of having CBD and to help distinguish it from similar conditions such as sarcoidosis. It is also the main test used in industry health programs to monitor whether disease is occurring among current and former workers who have been exposed to beryllium on the job. Sony VAIO VGN-CR21E/P Battery

The test can detect disease that is at an early stage, or can detect disease at more advanced stages of illness as well. The BeLPT can also be performed using cells obtained from a person's lung by a procedure called "bronchoscopy".


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