Silicon Dioxide |7631-86-9
Khoom Description
Cov tshuaj sib xyaw Silicon Dioxide, tseem hu ua silica (los ntawm Latin silex), yog ib qho oxide ntawm silicon nrog cov tshuaj formula SiO2.Nws tau paub txog nws qhov hardness txij thaum ancient sij hawm.Silica feem ntau pom muaj nyob rau hauv cov xuab zeb lossis quartz, nrog rau hauv cov phab ntsa ntawm tes ntawm diatoms.
Silica yog tsim nyob rau hauv ntau hom xws li fused quartz, siv lead ua, fumed silica (los yog pyrogenic silica), colloidal silica, silica gel, thiab aerogel.
Silica yog siv feem ntau hauv kev tsim cov iav rau qhov rais, haus iav, lub raj mis dej haus, thiab ntau lwm yam kev siv.Feem ntau ntawm cov fibers optical rau kev sib txuas lus kuj yog tsim los ntawm silica.Nws yog cov khoom siv tseem ceeb rau ntau cov khoom siv dawb ceramics xws li earthenware, stoneware, porcelain, as well as industrial Portland cement.
Silica yog ib qho khoom siv ntxiv hauv kev tsim cov khoom noj, qhov twg nws yog siv los ua tus neeg sawv cev ntws hauv cov khoom noj hmoov, lossis nqus dej hauv cov ntawv thov hygroscopic.Nws yog lub hauv paus tseem ceeb ntawm lub ntiaj teb diatomaceous uas muaj ntau yam kev siv xws li kev pom mus rau kev tswj kab.Nws tseem yog lub hauv paus tseem ceeb ntawm cov nplej husk tshauv uas siv, piv txwv li, hauv kev pom thiab kev tsim cov cement.
Nyias zaj duab xis ntawm silica zus ntawm silicon wafers ntawm thermal oxidation txoj kev yuav ua tau zoo heev nyob rau hauv microelectronics, qhov uas lawv ua raws li hluav taws xob insulators nrog siab tshuaj stability.Hauv kev siv hluav taws xob, nws tuaj yeem tiv thaiv cov silicon, khaws cov nqi, thaiv tam sim no, thiab txawm tias ua raws li txoj hauv kev tswj kom tsis txhob muaj cov dej ntws tam sim no.
Lub silica-raws li airgel tau siv nyob rau hauv Stardust spacecraft los mus sau extraterrestrial hais.Silica kuj tseem siv rau hauv kev rho tawm ntawm DNA thiab RNA vim nws lub peev xwm los khi rau cov nucleic acids nyob rau hauv lub xub ntiag ntawm chaotropes.Raws li hydrophobic silica nws yog siv los ua defoamer tivthaiv.Nyob rau hauv daim ntawv hydrated, nws yog siv nyob rau hauv cov tshuaj txhuam hniav raws li ib tug nyuaj abrasive tshem tawm cov quav hniav.
Nyob rau hauv nws lub peev xwm raws li ib tug refractory, nws yog ib qho tseem ceeb nyob rau hauv daim ntawv fiber ntau raws li ib tug high-temperature thermal tiv thaiv ntaub.Hauv cov tshuaj pleev ib ce, nws muaj txiaj ntsig zoo rau nws lub teeb-diffusing zog thiab ntuj absorbency.Colloidal silica yog siv los ua cawv txiv hmab thiab kua txiv hmab txiv ntoo.Hauv cov khoom siv tshuaj, silica pab hmoov ntws thaum cov ntsiav tshuaj raug tsim.Nws kuj tseem siv tau los ua cov khoom siv hluav taws xob ua kom sov hauv av hauv av qhov chaw ua haujlwm kub twj tso kua mis.
Specification
| Yam khoom | STANDARD |
| Qhov tshwm sim | Dawb hmoov |
| Purity (SiO2,%) | > = 96 |
| Roj nqus (cm3 / g) | 2.0 ~ 3.0 hli |
| Loss ntawm ziab (%) | 4.0-8.0 Nws |
| Loss ntawm ignition (%) | = <8.5 |
| PEB (m2/g) | 170-240 ib |
| pH (10% daws) | 5.0-8.0 Nws |
| Sodium sulfate (raws li Na2SO4,%) | =<1.0 |
| Arsenic (As) | = <3mg/kg |
| Lead (Pb) | = <5 mg/kg |
| Cadium (Cd) | = <1 mg/kg |
| Mercury (Hg) | = <1 mg/kg |
| Tag nrho cov hlau hnyav (raws li Pb) | = <20 mg/kg |
| Tag nrho cov phaj suav | = <500cfu/g |
| Salmonella spp. / 10g | Tsis zoo |
| Escherichia coli / 5g | Tsis zoo |
