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 Selenium powder GB code numbers 61502 CAS number 7782-49-2 Molecular formula Se Molecular weight 78.96 Content 99.9 The gray either the garnet powder or the black glass install thematter, hard and is crisp; Steams steam pressure 0.13kPa (356 ℃);Melting point 217 ℃; Boiling point 685 ℃; Solubility: Does notdissolve Yu Shui, is mellow, dissolves to the sulfuric acid, thenitric acid, the alkali, the carbon bisulfide; Density: Relativedensity (water =1) 4.81; Stability: Stable; The risk markings 15 (isharmful, is far away food); Main use: Uses in the systemsemiconducting material, the luxmeter, the solar battery, therectifier, the red glass 2. To environment influence: First, health danger Invasion way: The inspiration, the food enter. Health danger: The selenium has a stronger irritating quality to theskin mucous membrane. The massive inspiration may cause acutely arepoisoned, appear the nose to fill, to flow the tears, thepharyngalgia, the cough, the eye stabbing pain, the headache,dizziness, are disgusting, vomit and so on the symptom. The chronicity is poisoned: The long-term contact certain densityselenium, may have the headache, dizziness, is incapable, disgustingvomits, symptom and so on anorexia, diarrhea. Also may have the liverto be big, the liver function exceptionally, the hypotension, theheart movement slow and so on the plant nerve function disorderperformance Second, the toxicology academic attainments anticipate the environmentbehavior Toxicity: Is the micro poisonous kind. Acute toxicity: LD506700mg/kg (big mouse after mouth)  Selenium compounds in the environment have -2, +2, +4, +6 four valence to +4, +6 compounds exist majority. Industrial selenium compounds are commonly used selenium acid, sodium selenium, sodium selenite, hydrogen selenide, selenium dioxide, dichloro such as selenium oxide. Se non-toxic, but hydrogen selenide, the alkali metal-selenium and selenium permanganate toxicity permanganate very keen. Migration and transformation: selenium in natural water to Se0, Se2-, Se4 +, Se6 + state of existence. Wastewater sometimes Asia selenium ion (SeO32-), inMicro acid of water is stable in acidic conditions can be reduced to fine granular element selenium, in the micro-oxidation under alkaline conditions selenium ion. Pigment and dye wastewater containing selenium compounds, such as cadmium selenide (CdSe). Negative divalent forms of selenium compounds dissolved difficult, but not more than the current industrial use of selenium, selenium pollution in water just a local problem. In most cases, industrial areas and non-industrial areas selenium content of the river little difference. The selenium in the soil to the low solubility of iron form acid bound selenium in the soil, the general accumulated in iron-rich layer. Iron-rich soil contribute to the combination of selenium and selenium reduced the activity. Dangerous characteristic: May burn under the high temperature.Serodynamic combustion (decomposition) product: Oxidized selenium. ◆use: Uses in profession and so on battery, pigment, semiconductor. Sells the telephone：022-89939135 89937723 Handset：13820665839—13662175926 |
