about the chemical element the software testing framework Selenium software Infobox seleniumSelenium ... state in nature, but instead is obtained as a side product in the refining of other elements. Selenium ... or selenate compounds are also known, but are rare. The chief commercial uses for selenium ... with cadmium to form the Cadmium selenide Cadmium Selenide core. Selenium is a trace mineral that is essential to good health but required only in small amounts. Selenium is incorporated into proteins ... system. Selenium salts are toxic in large amounts, but trace amounts are necessary for cellular function ... in three deiodinase enzymes, which convert one thyroid hormone to another. Selenium requirements ... of selenium is a dense reddish gray solid. In terms of structure, it adopts a helical polymeric chain ... of glassy and crystalline selenium sulphur compounds author Kotkata M.F. et al. doi 10.1007 BF01107205 ... than in the dark, and is used in photocell s. Gray selenium resists oxidation by air and is not attacked by non oxidizing acids. With strong reducing agents, it forms polyselenides. Red selenium and related molecular allotropes The second major allotrope of Se is red selenium. The solid consists of individual ..., 2008. ISBN 978 3 11 019448 7 ref Elemental selenium produced in chemical reactions invariably appears ... author James E. House publisher Academic Press year 2008 isbn 0123567866 page 524 ref Selenium ... name house2008 ref Video of selenium heating http www.youtube.com watch?v nDEfR2Nw50s ref Isotopes main Isotopes of seleniumSelenium has six naturally occurring isotope s, five of which are stable ... as fission products , along with Selenium 79 sup 79 sup Se , which has a half life of 327,000 years .... Twenty three other unstable isotopes have been characterized. See also Selenium 79 for more ... waste . Occurrence File Selenium native.jpg thumb left Native selenium See also Category Selenide minerals Native selenium is a rare mineral, which does not usually form good crystals, but, when it does ... more details
Selenium fluoride may refer to Selenium hexafluoride selenium VI fluoride , SeF sub 6 sub Selenium tetrafluoride selenium IV fluoride , SeF sub 4 sub disambig simple Selenium fluoride ... more details
Selenium oxide may refer to either of the following compounds Selenium dioxide , SeO sub 2 sub Selenium trioxide , SeO sub 3 sub disambig simple Selenium oxide ... more details
saved book title Selenium subtitle An overview cover image Selen 1.jpg cover color Selenium An overview Overview Selenium Isotopes Isotopes of selenium Miscellany selenium deficiency Category Wikipedia books on chemical elements Category Selenium Wikipedia books on elements ... more details
Selenium chloride may refer to either of the following Selenium monochloride , Se sub 2 sub Cl sub 2 sub Selenium tetrachloride , SeCl sub 4 sub disambig simple Selenium chloride ... more details
Selenium sulfide can refer to either of the following Selenium disulfide , SeS sub 2 sub Selenium hexasulfide , Se sub 2 sub S sub 6 sub disambig ... more details
one source date September 2011 Infobox software name Selenium logo Image Seleniumlogo.png 200 px Selenium logo caption Demonstration of the Selenium collapsible yes developer status Active latest release ... Apache License 2.0 website URL http seleniumhq.org Selenium is a portable software testing Software framework framework for web application s. Selenium provides a record playback tool for authoring tests without learning a test scripting language Selenium IDE . It also provides a test domain specific language Selenese ref http seleniumhq.org docs 02 selenium ide.html selenium commands selenese Selenium Commands Selenese Selenium Documentation, retrieved September 9, 2011 ref to write tests in a number ... programming language Ruby . The tests can then be run against most modern web browser s. Selenium deploys on Microsoft Windows Windows , Linux , and Macintosh platforms. History Selenium was originally ... , and can be downloaded and used without charge. The latest side project is Selenium Grid, which provides a hub allowing the running of multiple Selenium tests concurrently on any number of local or remote systems, thus minimizing test execution time. Selenium components Selenium IDE Selenium IDE is a complete integrated development environment IDE for Selenium tests. It is implemented as a Add on Mozilla ... as Selenium Recorder. Selenium IDE was originally created by Shinya Kasatani and donated to the Selenium ... quickly. Scripts are recorded in Selenese , a special test scripting language for Selenium. Selenese ... IDs, names, or XPath as needed Autocomplete for all common Selenium commands Software walkthrough ... Ruby scripts, or other formats Support for Selenium user extensions.js file Option to automatically assert the title of every page Selenium Client API As an alternative to writing tests in Selenese, tests can also be written in various programming languages. These tests then communicate with Selenium by calling methods in the Selenium Client API. Selenium currently provides client APIs for Java, C ... more details
Orphan date September 2011 The Selenium Cycle The Selenium Cycle is a biological cycle of selenium similar ... the reduced element to the initial state. In the selenium cycle it has been found that bacteria, fungi, and plants, especially species of Astragalus , metabolize the most oxidized forms of selenium ... selenium of valence zero to selenium of valence 6. Evidence for a selenium cycle is found through the study of selenium accumulator plants. These plants are found in semi arid, seleniferous soils. The plants biosynthesize forms of organic selenium compounds and release the compounds into the soil when they decay. If the compounds were not oxidized, then an increase in organic selenium would be seen, but selenium in these areas is mainly inorganic. ref name Shrift cite journal doi 10.1038 2011304a0 author Shrift, A. year 1964 title A Selenium Cycle in Nature? journal Nature volume 201 pages 1304 1305 pmid 14151413 issue 4926 ref Selenium Cycle in Aquatic Ecosystems There are three fates of dissolved selenium in an aquatic ecosystem 1. it can be absorbed or ingested by organisms 2. it can bind with particulate matter or sediments or 3. it can remain in free solution. Over time, most of the selenium is taken in by organisms or bound to particulate matter. When particulate matter settles, the selenium ..., selenium is usually in the sediments temporarily before being cycled back into the system. Immobilization Processes Selenium can be removed from the ecosystem and bound in sediment through natural .... After selenium is in the sediment, other chemical and microbial reduction may occur, causing insoluble organic, mineral, elemental, or adsorbed selenium. Some organic forms may be released into the atmosphere ... release from plants. Immobilization processes effectively remove selenium from the ecosystem, especially in slow moving or still water areas. Mobilization Processes Selenium is made available to the food ... of inorganic and organic selenium by plant roots and microorganisms. The second process is biological ... more details
Selenium disulfide OtherNames Selenium sulfide Section1 Chembox Identifiers CASNo 7488 56 4 CASNo Ref cascite correct CAS PubChem 24087 MeSHName Selenium sulfide ChemSpiderID Ref chemspidercite ... Section8 Chembox Related OtherAnions Selenium dioxide br Selenic acid br Selenious acid OtherCations Hydrogen sulfide OtherFunctn Function OtherCpds Selenium disulfide is an inorganic compound with the approximate formula SeS sub 2 sub . Both sulfur and selenium catenate form chains and rings readily, and mixtures of selenium and sulfur likewise give rise to numerous alloys . ref name Steudel Cyclic selenium sulfides R. Steudel, R. Laitinen, Topics in Current Chemistry, 1982 , 102, 177 197 ref This compound is not an analogue of sulfur dioxide . Medicinal selenium disulfide The material commercially called selenium disulfide is sold as an Antifungal medication antifungal agent in shampoo ... fungi. ref name autogenerated1 http pharmacycode.com Selenium IV sulfide.html Selenium IV sulfide ... selenium disulfide.html Chemicals of Selenium .Se Bot generated title ref ref http dermnetnz.org treatments ... prescription . At the 2.5 strength, selenium disulfide is also used on the body to treat tinea versicolor ... File 1,2,3 Se3S5.svg thumb left Structure of 1,2,3 Se sub 3 sub S sub 5 sub Selenium disulfide has a composition that approximates to SeS sub 2 sub and is sometimes called selenium sulfide ... of S and Se atoms, Se sub n sub S sub 8 nowiki &minus nowiki n sub. . ref name Steudel Selenium disulfide ... lic jewellery . Other selenium sulfides Many selenium sulfides are known. A useful means for characterization ..., Y. Hiltunen, R. S. Laitinen, T. A. Pakkanen Selenium 77 NMR spectroscopic study of the decomposition ... sub 4 sub S sub 2 sub Inorg. Chem., 1991, 30, pp 3679 3682. DOI 10.1021 ic00019a022 ref Selenium monosulfide SeS is the only selenium compound so far identified as a carcinogen in animal s. ref http www.scorecard.org chemical profiles html selenium.html ref Selenium monosulfide, along with elemental ... more details
Selenium acid may refer to either of the following Selenious acid , H sub 2 sub SeO sub 3 sub Selenic acid , H sub 2 sub SeO sub 4 sub Hydroselenic acid , H sub 2 sub Se disambig simple Selenium acid ... more details
Image MADDIDA Selen Rectifier.JPG thumb right Selenium rectifiers used in 1950s MADDIDA computer. A selenium ... charger applications. The photoelectric and rectifying properties of selenium were observed by C. E .... Compared with the earlier copper oxide rectifier, the selenium cell could withstand higher voltage ... industry , IET, 1990 ISBN 0863412270 pages 13, 18 ref Construction File Selenium rectifier.agr.jpg thumb Selenium rectifier from 1960s. Each plate is 1 inch square. Selenium rectifiers are made ... . A much thicker layer of selenium 50 to 60 m which has been doped with a halogen is deposited on top of the thin metal plating. The selenium is then converted into polycrystalline gray hexagonal ... to providing a mounting place for the selenium disks. Plates can be stacked indefinitely to withstand higher voltages. Stacks of thousands of miniature selenium disks have been used as high voltage ... tube rectifiers had efficiencies of only 60 compared to the 85 of selenium rectifiers, partially because vacuum tube rectifiers required heating. Selenium rectifiers have no warm up time unlike high vacuum rectifiers. Selenium rectifiers were also cheaper and simpler to specify and install than ... at high voltages . Selenium rectifiers had the capability to act as current limiters which can temporarily .... Properties A selenium rectifier is about the same size as copper oxide rectifiers, but much larger than a silicon or germanium diode. Selenium rectifiers have a long but not indefinite service life ... volts, and has a forward voltage drop around 1 volt, which limits the efficiency at low voltages. Selenium ... & Co., Inc. 1968 chapter 13 ref Replacement Selenium rectifiers had a shorter lifespan than desired ... of03 018 of03 018.pdf Selenium, U.S. Department of the Interior ref They are still manufactured for exact ... chargers. ref http www.universalrectifiers.com Selenium 20Stacks.htm Universal Rectifiers website ref References commons category Selenium rectifiers Reflist Category Diodes Category Selenium de ... more details
Orphan date September 2011 Selenium yeast , produced by fermenting Saccharomyces cerevisiae in a selenium rich media, is a recognized source of organic food form selenium. ref Schrauzer G. Selenium yeast ... all of the selenium structurally substitutes for sulfur in the amino acid methionine thus ... and becomes part of yeast protein. It is this metabolic route that makes selenium yeast valuable in animal and human nutrition, since it offers the same organic form of selenium produced by food chain autotrophs i.e., most plants and certain blue green algae . ref Schrauzer G. Selenium yeast ... 73 112. ref Human health applications Selenium is physiologically essential and may also offer a protective ... of selenium in the human body relationship with different diseases. Sci Tot Environ 2000 249 347 371. ref The organic form of selenium provided by selenium yeast has been shown to differ in bioavailability and metabolism compared with inorganic e.g., selenate, selenite forms of dietary selenium .... J Nutr 2000 130 1653 1656. ref Dietary supplementation using selenium yeast has been associated .... A short term intervention trial with selenate, selenium enriched yeast and selenium enriched milk effects on oxidative defence regulation. Br J Nutr 2008 99 883 892. ref Furthermore, selenium yeast has been used in a wide range of studies aimed at examining the importance of selenium status in the incidence ... in APP PS1 mice. Free Rad Biol Med 2009 46 1527 1533. ref Cancer . Dietary supplementation with selenium yeast has been used to study the effects of selenium status and the risk of developing cancers or precancerous lesions. ref Combs GJ, Lu J. Selenium as a cancer preventive agent. In Hatfield D, Berry M, eds. Selenium Its molecular biology and role in human health, 2nd ed. New York Springer ... of a selenium yeast supplement in patients with carcinoma of the skin had promising secondary endpoint ... lung cancer mortality. ref Clark LC, Combs GF, Jr., Turnbull BW, et al. Effects of selenium ... more details
In high concentrations, selenium acts as an environmental contaminate. Sources of pollution include waste materials from certain mining, agricultural, petrochemical, and industrial manufacturing operations. In Belews Lake North Carolina, 19 species of fish were eliminated from the lake due to 150 200 ug Se L wastewater discharged from 1974 to 1986 from a coal fired power plant. At the Kesterson National Wildlife Refuge in California, thousands of fish and waterbirds were poisoned by selenium in agricultural irrigation drainage. Substantial physiological changes may occur in fish with high tissue concentrations of selenium. Fish affected by selenium may experience swelling of the gill lamella zoology lamella e, which impedes oxygen diffusion across the gills and blood flow within the gills. Respiratory capacity is further reduced due to selenium binding to hemoglobin . Other problems include degeneration of liver tissue, swelling around the heart, damaged egg follicles in ovaries, cataracts, and accumulation of fluid in the body cavity and head. Selenium often causes a malformed fish .... Adult fish may appear healthy despite their inability to produce viable offspring. Selenium is Bioaccumulation ... when water concentrations are in the .5 to .8 ug Se L range. Inorganic selenium bioaccumulates more readily in phytoplankton than zooplankton. Phytoplankton can concentrate inorganic selenium ..., as predators consume selenium rich prey.It is recommended that a water concentration of 2 ug Se L be considered highly hazardous to sensitive fish and aquatic birds. Selenium poisoning can be passed from parents to offspring through the egg, and selenium poisoning may persist for many generations.Reproduction ... invertebrates can tolerate selenium concentrations up to 300 ug Se g in their diet. ref cite book last Lemly first Dennis authorlink coauthors title Selenium Assessment in Aquatic Ecosystems ... url http books.google.com books?id qGH37iOW7yMC&dq Selenium Assessment in Aquatic Ecosystems&printsec ... more details
chembox verifiedrevid 432484439 ImageFileL1 Selenium hexafluoride 2D.png ImageSizeL1 ImageFileR1 Selenium hexafluoride 3D balls.png ImageSizeR1 IUPACName selenium hexafluoride, OtherNames selenium VI fluoride, selenium fluoride Section1 Chembox Identifiers CASNo Ref cascite correct ?? CASNo 7783 79 1 PubChem 24558 RTECS VS9450000 SMILES F Se F F F F F InChI 1S F6Se c1 7 2,3,4,5 6 Section2 Chembox Properties Formula SeF sub 6 sub MolarMass 192.9534 g mol Appearance colourless gas Density 7.887 g cm sup 3 sup ref name CRC MeltingPt 34.6 C ref name CRC RubberBible86th ref BoilingPt 46.6 C, sublimes Solubility insoluble RefractIndex 1.895 Section3 Chembox Structure CrystalStruct Orthorhombic , Pearson ... Holleman Elsevier 2001 ISBN 0 12 352651 5 ref DeltaHc Entropy HeatCapacity Selenium hexafluoride is the inorganic ..., 2010 ref It is not widely encountered and has no commercial applications. ref Bernd E. Langner Selenium and Selenium Compounds in Ullmann s Encyclopedia of Industrial Chemistry, Wiley VCH, 2002, Weinheim DOI 10.1002 14356007.a23 525 ref Structure, preparation, and reactions Like many compounds of selenium ... ref cite journal doi 10.1002 9780470132326.ch44 title Sulfur, Selenium, and Tellurium Hexafluorides ... of bromine trifluoride BrF sub 3 sub with selenium dioxide . The crude product is purified by sublimation ... B, Bonmann S, Eidenschink I. Selenium Inorganic Chemistry Encyclopedia of Inorganic Chemistry Ed. R. Bruce King 1994 John wiley & Sons ISBN 0 471 93620 0 ref Safety Selenium hexafluoride is toxic even ... 215 title Medical Management Guidelines for Selenium Hexafluoride SeF6 accessdate July 24, 2010 ref In the U.S., Occupational Safety and Health Administration OSHA and ACGIH standards for selenium hexafluoride ... reflist External links http www.atsdr.cdc.gov tfacts183.html ATSDR ToxFAQs Selenium Hexafluoride ... page for SeF6 Selenium compounds Category Fluorides Category Selenium compounds Category Chalcohalides de Selenhexafluorid fa nl Seleenhexafluoride ja simple Selenium ... more details
Refimprove date November 2010 chembox Verifiedfields changed verifiedrevid 464388785 Name Selenium trioxide ImageFileL1 Selenium trioxide.svg ImageSizeL1 121 ImageNameL1 Structural formula of the monomer as found in the gas phase ImageFileR1 Selenium trioxide 3D spacefill.png ImageSizeR1 121 ImageNameR1 Space filling model of the monomer as found in the gas phase Reference ref name hand Cite book last Lide first David R. author link last2 first2 author2 link publication date date year 1998 title Handbook of Chemistry and Physics edition 87 volume series publication place Boca Raton, FL place publisher CRC Press id isbn 0 8493 0594 2 doi oclc pages 4 81 url accessdate postscript None ref OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 103019 InChI 1 O3Se c1 4 2 3 InChIKey VFLXBUJKRRJAKY UHFFFAOYAC SMILES O SeH2 O O StdInChI Ref stdinchicite correct chemspider StdInChI 1S O3Se c1 4 2 3 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey VFLXBUJKRRJAKY UHFFFAOYSA N CASNo Ref cascite changed ?? CASNo 13768 86 0 PubChem 115128 ... Section3 Chembox Structure CrystalStruct tetragonal Section7 Chembox Hazards EUClass not listed Selenium trioxide Selenium Se Oxygen O sub 3 sub is a chemical compound used in the manufacture of photoelectric ... SeO sub 4 sub and SO sub 3 sub . The compound is thermodynamically unstable with respect to selenium ... selenate s. Structure The molecular shape of selenium trioxide is triagonal planar. Selenium trioxide is a nonpolar molecule. the bonds between the selenium and the oxygen are double bonds. The bond ... Wilhelm date 1963 10 02 title The Chemistry of Selenium Trioxide journal Angewandte Chemie International Edition in English volume 2 issue 11 pages 691 692 doi 10.1002 anie.196306913 Selenium compounds DEFAULTSORT Selenium Trioxide Category Oxides Category Selenium compounds Category Inorganic ... ru simple Selenium trioxide sv Selentrioxid zh ... more details
chembox Verifiedfields changed verifiedrevid 464388588 Name Selenium oxybromide ImageFile ImageSize ImageName Selenium oxybromide OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 74220 PubChem 82242 InChI 1 Br2OSe c1 4 2 3 InChIKey ZWTYAOCEBBZVQQ UHFFFAOYAF SMILES Br Se Br O StdInChI Ref stdinchicite correct chemspider StdInChI 1S Br2OSe c1 4 2 3 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey ZWTYAOCEBBZVQQ UHFFFAOYSA N CASNo Ref cascite changed ?? CASNo 7789 51 7 Section2 Chembox Properties Formula SeOBr sub 2 sub MolarMass 254.77 g mol Appearance red yellow solid Density 3.38 g cm , solid MeltingPt 41.6 C BoilingPt decomposes at 220 C Solubility reacts SolubleOther soluble in carbon disulfide , benzene , carbon tetrachloride ref name hand Cite book last Lide first David R. author link last2 first2 author2 link publication date date year 1998 title Handbook of Chemistry and Physics edition 87 volume series publication place Boca Raton, FL place publisher CRC Press id isbn 0 8493 0594 2 doi oclc pages 4 81 url accessdate ... Chembox Hazards EUClass Selenium oxybromide Selenium Se Oxygen O Bromine Br sub 2 sub is a chemical compound . Preparation Selenium oxybromide can be prepared through the reaction of selenium dioxide and selenium tetrabromide . Selenium and selenium dioxide are reacted with bromine to form selenium monobromide and selenium tetrabromide. Dissolving the selenium dioxide in the tetrabromide will produce ... title Selenium oxybromide ref 2 Se 2 Br Se sub 2 sub Br sub 2 sub Se sub 2 sub Br sub 2 sub 6 Br SeBr sub 4 sub SeBr sub 4 sub SeO sub 2 sub 2 SeOBr sub 2 sub Properties Selenium oxybromide is a reddish brown solid with a low melting point 41.6 C and chemical properties similar to selenium oxychloride ... taking place in the liquid state. Selenium will dissolve in it, forming Se sub 2 sub Br sub 2 sub . Iron ... reflist Selenium compounds Category Selenium compounds Category Oxohalides Category Inorganic ... more details
chembox verifiedrevid 444677336 Name Selenium monochloride ImageFile ImageSize ImageName IUPACName Selenium monochloride OtherNames Dichlorodiselenide, Diselenium dichloride, Selenium chloride, 1,2 dichlorodiselane Section1 Chembox Identifiers CASNo Ref cascite correct ?? CASNo 10025 68 0 RTECS PubChem ... 22 26 36 37 39 45 FlashPt Section8 Chembox Related OtherAnions OtherCations Selenium monochloride is an inorganic compound with the formula Se sub 2 sub Cl sub 2 sub . Although it is called selenium monochloride ... , chlorine , and elemental selenium . ref Greenwood&Earnshaw2nd ref Selenium monochloride is mainly used as a reagent for the synthesis of Se containing compounds. Structure and properties Selenium ... . ref Marc Lamoureux and John Milne Selenium chloride and bromide equilibria in aprotic solvents a sup ... Preparation Selenium monochloride was originally produced by the chlorination of selenium. ref J. J ... of Selenium Monochloride and Monobromide, J. Am. Chem. Soc. , 1925, 48 , 772 774. DOI 10.1021 ja01680a025 ref An improved method involves the reaction of a mixture of selenium, selenium dioxide ... sub 2 sub 4 HCl 2 Se sub 2 sub Cl sub 2 sub H sub 2 sub O A dense layer of selenium monochloride ... of selenium with oleum and hydrochloric acid ref name Feher 2 Se 2 SO sub 3 sub 3 HCl Se sub 2 sub Cl sub 2 sub H sub 2 sub SO sub 3 sub SO sub 2 sub OH Cl The crude selenium monochloride product is collected via distillation. Reactions Selenium monochloride is an electrophilic selenizing agent, and thus it reacts with simple alkene s to give bis chloroalkyl selenide and bis chloroalkyl selenium ... is replaced with a selenium atom. ref name Back Finally, the compound has been used to introduce bridging selenium ligands between the metal atoms of some iron and chromium carbonyl complexes. ref name Back References reflist colwidth 30em Selenium compounds Category Selenium compounds Category Chlorides Category Chalcohalides fa simple Selenium monochloride ... more details
chembox verifiedrevid 438850594 Name Selenium oxydichloride ImageFileL1 SeOCl2.png ImageSizeL1 120px ImageNameL1 Structure of the selenium oxydichloride molecule ImageFileR1 Selenium oxydichloride 3D vdW.png ImageSizeR1 120px ImageNameR1 3D model of the selenium oxydichloride molecule IUPACName Selenium oxychloride OtherNames Seleninyl chloride Section1 Chembox Identifiers SMILES O Se Cl Cl CASNo Ref cascite correct ?? CASNo 7791 23 3 PubChem 24647 RTECS VS7000000 EINECS 232 244 0 InChI 1S Cl2OSe c1 4 2 3 Section2 Chembox Properties Formula SeOCl sub 2 sub MolarMass 165.87 g mol Appearance colorless liquid Density 2.43 g cm sup 3 sup , liquid Solubility hydrolyzes violently SolubleOther soluble in carbon disulfide CS sub 2 sub , carbon tetrachloride CCl sub 4 sub , chloroform , benzene , toluene br decomposes in hydrochloric acid HCl MeltingPt 10.9 C BoilingPt 177.2 C Viscosity RefractIndex 1.651 20 C Section3 Chembox Structure MolShape trigonal pyramidal Dipole Section7 Chembox Hazards ExternalMSDS MainHazards RPhrases 14 23 25 33 35 50 53 SPhrases 26 36 37 39 45 60 61 NFPA H 3 NFPA F 0 NFPA R 1 Section8 Chembox Related Function compounds OtherFunctn Thionyl chloride SOCl sub 2 sub , Phosphoryl chloride POCl sub 3 sub Selenium oxydichloride is the inorganic compound with the formula SeOCl sub 2 sub . It is a liquid with a high dielectric constant 55 and high specific conductance, and for these reasons is an attractive solvent. Structurally, it is a close chemical relative of thionyl ... Selenium oxydichloride can be prepared by several methods, and a popular one involves the conversion of selenium dioxide to dichloroselenious acid followed by dehydration ref G. B. L. Smith, Julius Jackson, J. J. Pitha, Eva Blanchard Selenium IV Oxychloride Inorganic Syntheses, 1950, Volume 3 ... chemistry redistribution reaction of selenium dioxide and selenium tetrachloride . The compound hydrolyzes readily. References reflist Selenium compounds Category Selenium compounds Category Oxohalides ... more details
chembox verifiedrevid 408615992 Name Selenium dioxide ImageFile Selenium dioxide.png ImageName Selenium dioxide ImageFile1 Selenium dioxide chain 3D balls.png ImageSize1 250px ImageName1 Ball and stick model of a chain in crystalline selenium dioxide ImageFile2 Selenium dioxide.jpg IUPACName OtherNames Selenium IV oxide br Selenous anhydride Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite ... white, ref name chemox or red ref name chemox http msds.chem.ox.ac.uk SE selenium dioxide.html ... Selenium disulfide OtherCations Sulfur dioxide br Tellurium dioxide OtherFunctn Selenium trioxide Function selenium oxide s OtherCpds Selenous acid Selenium dioxide is the chemical compound with the chemical ... compounds of selenium . Properties SeO sub 2 sub is a polar molecule, with the dipole moment pointed from the midpoint of the two oxygen atoms to the selenium atom. Solid SeO sub 2 sub is a one dimensional polymer , the chain consisting of alternating selenium and oxygen atoms. Each Se atom ... sauce and can burn the nose and throat on inhalation. Gaseous selenium dioxide adopts a bent structure very similar to that of sulfur dioxide . Dissolution of SeO sub 2 sub in selenium oxydichloride ... selenous selenious acid. ref name Holl&Wib Often the terms selenous acid and selenium dioxide are used ... NaOH Na sub 2 sub SeO sub 3 sub H sub 2 sub O Preparation Selenium dioxide is prepared by oxidation of selenium by burning in air, nitric acid or by reaction with hydrogen peroxide , but perhaps the most ... 2 sub SeO sub 3 sub unicode SeO sub 2 sub H sub 2 sub O Occurrence The natural form of selenium dioxide ... CV4P0229 ref The selenium starting material is redox reduced to selenium, and precipitates as a red ... Coxon, J. M. Dansted, E. Hartshorn, M. P. title Allylic Oxidation with Hydrogen Peroxide Selenium ... are alkyl or aryl . As a colorant Selenium dioxide imparts a red colour to glass . It is used in small ... glass. In larger quantities, it gives a deep ruby red colour. Selenium dioxide is the active ... more details
chembox Verifiedfields changed verifiedrevid 477163163 Name Selenium tetrachloride ImageFile1 SeCl4 from alpha xtal 1981 CM 3D ellipsoids.png ImageFile2 TeCl4structure.jpg ImageSize2 ImageName2 IUPACName Selenium tetrachloride OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 59590 InChI 1 Cl4Se c1 5 2,3 4 InChIKey LNBXMNQCXXEHFT UHFFFAOYAD SMILES Cl Se Cl Cl Cl StdInChI Ref stdinchicite correct chemspider StdInChI 1S Cl4Se c1 5 2,3 4 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey LNBXMNQCXXEHFT UHFFFAOYSA N CASNo Ref cascite changed ?? CASNo 10026 03 6 RTECS VS7875000 PubChem 66205 Section2 Chembox Properties Formula SeCl sub ... 323527 Selenium tetrachloride accessdate 2008 07 02 publisher Sigma Aldrich date ref FlashPt non flammable Section8 Chembox Related OtherAnions Selenium tetrafluoride br Selenium tetrabromide br Selenium dioxide OtherCations Dichlorine monoxide br Sulfur tetrachloride br Tellurium tetrachloride Selenium ... selenium chlorides, the other example being selenium monochloride , Se sub 2 sub Cl sub 2 sub . SeCl sub 4 sub is used in the synthesis of other selenium compounds. Synthesis and structure The compound is prepared by treating selenium with chlorine ref Henry G. Nowak, John F. Suttle Selenium IV Chloride ... selenium is heated, the product sublimes from the reaction flask. The volatility of selenium tetrachloride can be exploited to purification of selenium. Solid SeCl sub 4 sub exhibits a cubane geometry ... condensation. Reactions Selenium tetrachloride can be reduced in situ to the dichloride using triphenylstibine SeCl sub 4 sub SbPh sub 3 sub SeCl sub 2 sub Cl sub 2 sub SbPh sub 3 sub Selenium tetrachloride ... 3 sub 4 HCl Upon treatment with selenium dioxide , it gives selenium oxychloride ref name Greenwood SeCl sub 4 sub SeO sub 2 sub 2SeOCl sub 2 sub References reflist Selenium compounds Category Selenium ... nl Seleentetrachloride pt Tetracloreto de sel nio ru simple Selenium tetrachloride ... more details
chembox Verifiedfields changed verifiedrevid 477000495 ImageFile Selenium tetrafluoride gas 3D balls.png ... Autoignition NFPA 704 NFPA H 3 NFPA F ? NFPA R 2 NFPA O W Section8 Chembox Related OtherAnions selenium dioxide , selenium IV chloride , selenium IV bromide OtherCations sulfur tetrafluoride , tellurium IV fluoride OtherCpds selenium difluoride , selenium hexafluoride Selenium tetrafluoride Selenium ... can be employed and it is a liquid rather than a gas. Selenium tetrafluoride was first synthesized by the reaction of selenium with fluorine by Paul Lebeau in 1907. ref cite journal title Action of Fluorine on Selenium Tetrafluoride of Selenium author Paul Lebeau journal Comptes Rendus Acad ... of preparation include fluorinating elemental selenium with chlorine trifluoride 3 Se 4 ClF sub 3 sub 3 SeF sub 4 sub 2 Cl sub 2 sub and reacting sulfur tetrafluoride with selenium dioxide SF sub 4 sub SeO sub 2 sub SeF sub 4 sub SO sub 2 sub Selenium in SeF sub 4 sub has an oxidation state of 4 ... pairs around the selenium atom. The axial Se F bonds are 177 picometre pm with an F Se F bond ... leading to a distorted octahedral coordination around the selenium atom. In the solid the selenium ... sub 5 sub , and BF sub 3 sub . ref cite journal title Selenium tetrafluoride adducts. II. Adducts with boron ... reflist refbegin Selenium Inorganic Chemistry Krebs. B., Bonmann S., Eidenschink I. Encyclopedia of Inorganic Chemistry 1994 John Wiley and Sons ISBN 0 471 93620 0 refend cite journal title On selenium ... title The preparation and properties of selenium tetrafluoride and oxyfluoride author E. E. Aynsley ... 1231 doi 10.1039 JR9520001231 cite journal title Some properties of selenium tetrafluoride author ... JR9530003617 cite journal title Structure of Selenium Tetrafluoride author H. J. M. Bowen journal Nature ... title Structure of Selenium Tetrafluoride author F. Lachman journal Nature Nature journal year 1953 ... diffraction of the molecular structures of sulphur hexafluoride, sulphur tetrafluoride, selenium ... more details
chembox verifiedrevid 427848433 Name Selenium hexasulfide Reference ref name hand Citation last Lide first David R. author link last2 first2 author2 link publication date date year 1998 title Handbook of Chemistry and Physics edition 87 volume series publication place Boca Raton, FL place publisher CRC Press id isbn 0 8493 0594 2 doi oclc pages 4 81 url accessdate ref ImageFile ImageSize ImageName Selenium hexasulfide OtherNames Section1 Chembox Identifiers CASNo Ref cascite correct ?? CASNo 75926 26 0 Section2 Chembox Properties Formula Se sub 2 sub S sub 6 sub MolarMass 350.32 g mol Appearance orange needles Density 2.44 g cm sup 3 sup Solubility SolubleOther soluble in carbon disulfide MeltingPt 121.5 C BoilingPt Section3 Chembox Structure CrystalStruct Section7 Chembox Hazards EUClass not listed Selenium hexasulfide is a chemical compound with formula Se sub 2 sub S sub 6 sub . Its molecular structure consists of a ring of two selenium and six sulfur atoms, analogous to the S sub 8 sub allotrope of sulfur cyclooctasulfur and other selenium sulfide s with formula Se sub n sub S sub 8 n sub . ref name laitinen There are several isomer s depending on the relative placement of the selenium atoms in the ring 1,2 with the two Se atoms adjacent , 1,3 , 1,4 , and 1,5 with the Se atoms opposite . ref name maan Arto Maaninen, Tristram Chivers, Masood Parvez, Jarkko Pietik inen, and Risto S. Laitinen 1999 , Syntheses of THF Solutions of SeX sub 2 sub X Cl, Br and a New Route to Selenium Sulfides Se sub n sub S sub 8 n sub n 1 5 X ray Crystal Structures of SeCl sub 2 sub tht sub 2 sub ... Se8 and all other eight member cyclic selenium sulfides, except SeS7, and several six and seven ... A. Pakkanen 1989 , The 77s NMR spestroscopic Identification of Heterocyclic Selenium Sulfides Prepared ... , volume 43, pages 436 440. ref References reflist Selenium compounds Category Sulfides Category Selenium compounds Category Oxidizing agents inorganic compound stub ar ... more details
Infobox disease Name Selenium deficiency Image Se TableImage.png Caption Selenium DiseasesDB 11941 ICD10 ICD10 E 59 e 50 ICD9 ICD9 269.3 ICDO OMIM MedlinePlus eMedicineSubj eMedicineTopic MeshID Selenium deficiency is relatively rare in healthy well nourished individuals. Few cases have been reported. Causes It can occur in patients with severely compromised intestine intestinal function, those undergoing total parenteral nutrition , those who have had gastrointestinal bypass surgery, and also on advanced aged people over 90 . ref cite journal first1 Giovanni last1 Ravaglia first2 Paola last2 Forti first3 Fabiola last3 Maioli first4 Luciana last4 Bastagli first5 Andrea last5 Facchini first6 Erminia ... medical source date March 2012 ref Alternatively, people dependent on food grown from selenium deficient ... effects associated with cholesterol lowering drugs statins resembles the pathology of selenium ... . Selenoprotein P ref name pmid17508906 cite journal doi 10.1089 ars.2007.1528 title From Selenium ... Antioxidants & Redox Signaling volume 9 issue 7 pages 775 ref is a better indicator of selenium nutritional ... DW last4 Xu first4 J last5 Burk first5 RF title Effectiveness of selenium supplements in a low selenium ... ref Presentation Selenium deficiency in combination with Coxsackievirus infection can lead to Keshan disease , which is potentially fatal. Selenium deficiency also contributes along with iodine deficiency ... Beck Osteoarthropathy in Rural Tibet in Relation to Selenium and Iodine Status year 1998 last1 Moreno ... caused by other nutritional, biochemical, or infectious diseases. Selenium is also necessary for the conversion ... cite web url http www.merck.com mmpe sec01 ch005 ch005i.html title Selenium Mineral Deficiency ... deficient in selenium. Studies in Jiangsu Province of China have indicated a reduction in the prevalence of these diseases by taking selenium supplements. ref http ods.od.nih.gov factsheets selenium.asp ... Selenium Link FA de de Selenmangel ja ... more details
A selenium meter is a light measuring instrument based on the photoelectric properties of selenium . The most common use of such light meter s is measuring the exposure value for photography. The electric part of such a meter is an electromagnetic measuring instrument which is connected to the anode and cathode of a selenium photo cell that produces more or less electric power when exposed to more or less light. The optical part of such a meter is a window in front of the photo cell s light sensitive side. The window s surface is usually structured like a honeycomb made of convex lenses. This type of window helps to bundle the light coming from the direction in which the photo cell is pointed. The mechanical part of a selenium meter is an analog calculator which accepts exposure value and film speed as input parameters for showing the possible aperture and shutter speed combinations for correct exposure. Types of meters Match needle meters File Math needle meter.jpg thumb A match needle meter of the Zenit camera Zenit . The simplest type of match needle selenium meter shows a clockhand on the meter s scale. This can be moved by turning one slice of the analog calculator. When the clockhand matches the instrument s needle the EV value is set right on the calculator. The picture on the right shows the device of the Zenit camera Zenit E model, mounted on a left side of the camera. The inner flat circle rotates with the help of the knob and sets the film sensitivity visible in both ... manual of Zenith E photocamera ref Another type is common especially where a selenium meter is built ... didn t know any limits of complication so that even further steps were gone to use selenium photo ... wonder that a handful of cameras were made which had automatic exposure control driven by a selenium ... for expensive rangefinder camera rangefinder or SLR cameras was to offer a selenium meter ... in the photograph References references From Camerapedia Selenium meter 4 August 2007 Category ... more details
Selenium Se has six naturally occurring isotope s, five of which are stable sup 74 sup Se, sup 76 sup Se, sup 77 sup Se, sup 78 sup Se, and sup 80 sup Se. The last three also occur as fission products , along with Selenium 79 sup 79 sup Se which has a half life of 327,000 years, ref name life http www.ptb.de en org 6 nachrichten6 2010 60710 en.htm The half life of sup 79 sup Se ref ref cite journal last1 Jorg first1 Gerhard last2 Buhnemann first2 Rolf last3 Hollas first3 Simon last4 Kivel first4 Niko last5 Kossert first5 Karsten last6 Van Winckel first6 Stefaan last7 Gostomski first7 Christoph Lierse v. title Preparation of radiochemically pure 79Se and highly precise determination of its half life journal Applied Radiation and Isotopes volume 68 pages 2339 51 year 2010 doi 10.1016 j.apradiso.2010.05.006 pmid 20627600 issue 12 ref and sup 82 sup Se which has a very long half life 10 sup 20 sup yr, decaying via double beta decay to Krypton sup 82 sup Kr and for practical purposes can be considered to be stable. 23 other unstable isotopes have been characterized, the longest lived being sup 79 sup Se with a half life 327,000 years, sup 75 sup Se with a half life of 120 days, and sup 72 sup Se with a half life of 8.40 days. All other isotopes have half lives less than 8 hours, most less than 38 seconds, which of these, sup 73 sup Se is the most stable, with a half life of 7.15 hours ... 3 align center Stable 0 0.2377 28 Selenium 79 sup 79 sup Se ref group n Long lived fission product ... use expanded uncertainties. See also SeleniumSelenium 79 References reflist Isotope masses from ... data selected from the following sources. See editing notes on Talk Isotopes of selenium this article ... CRC Press isbn 978 0849304859 Isotope nav element selenium lighter Isotopes of arsenic heavier Isotopes of bromine Category Selenium Category Isotopes of selenium Category Lists of isotopes by element Selenium ca Is tops del seleni nl Isotopen van seleen ja zh ... more details
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