Silica. Faib nyob rau hauv cov xwm, txoj kev tau, siv

Silicon dioxide (tshuaj mis: SiO2, silica) - yog ib tug tsis muaj kob crystalline, glassy los yog amorphous khoom. Qhov no mineral yog nyob rau hauv daim ntawv ntawm quartz xuab zeb yog dav siv nyob rau hauv kev tsim kho, nyob rau hauv qhuav ntawm khoom uas siv tshuaj thiab xov tooj cua, nyob rau hauv chaw ua dav hlua kev tsim kho thiab ntau lwm yam industries.

Faib Silica nyob rau hauv cov xwm

Silica yog muaj nyob rau hauv lub ntiaj teb ua kiav txhab raws li ib tug sib tov nrog ib co lwm yam minerals (xa mus rau raws li granite), thiab ib tug silicate, ib feem ntawm lub pob zeb. Cov feem ntau lawm tab sis mineral - quartz, cristobalite yog npaum li cas rarer, chalcedony, tridymite, opal, lechatelierite (quartz iav). Tus zoo quartz muaju txoj kev ib tug thiaj li hu ua "tub ntxhais" quartz. Nrog lub tsheb txhob sibtsoo puas tsuaj ntawm cov pob zeb tsim quartz xuab zeb, uas, compacted, ua rau cov tsos ntawm quartzite thiab sandstone.

Rhinestone - qhov no yog feem ntau cov ntshiab quartz, tsis muaj kob. Nws muaju yuav luj kaum ntawm tons, thiab mus txog lengths ntawm ob peb meters. Tsis tas li ntawd, quartz tej zaum yuav loj uas muaj ntau yam impurities violet (amethyst), daj (citrine), dub (morion), muaj pa taws (rauchtopaz). Nyob rau hauv cov xwm, tseem muaj cryptocrystalline daim ntawv ntawm quartz: liab-liab carnelian, ntsuab-Kua chrysoprase, blue sapphire, zog-dawb lias jasper, onyx thiab agate xuab zeb, hornfels thiab silicon.

Cim "noble" opal, uas muaj colloidal hais ntawm niaj hnub lub cheeb ntawm txog 0.2 microns. Cov hais yog tau ntim nruj nreem rau hauv kom agglomerates ntawm dej uas lawv muaj tsawg tshaj li ib feem pua (nyob rau hauv feem ntau opals - txog xya feem pua). Ntuj silicon dioxide deposits yuav tau daim diatomite, Tripoli. Ntawm mineral ua zoo li ntawm diatoms, lub skeletons ntawm tej yam lub paj rwb. Nws yog ib feem ntawm lub stems ntawm nroj tsuag - xws li ib tug reed, horsetail, xyoob.

Yuav ua li cas kom tau silica?

Synthetic SiO2 yuav tau:

- los ntawm qhov kev txiav txim ntawm hydrochloric (HCl) los yog sulfuric (H2SO4) acids rau lub sodium silicate, tsawg kawg yog - nyob rau hauv lwm yam soluble silicates (qhov no yog qhov tseem ceeb txoj kev nyob rau hauv tsim lub teb chaws);

- siv colloidal silicon dioxide (los ntawm nws cov khov los yog coagulation nyob rau hauv qhov kev txiav txim ntawm F-ions, Na +);

- los ntawm hydrolysis ntawm lub pob zeb ntais fluoride SiF4, pob zeb ntais tetrachloride SiCl4, tetraethoxysilane (C2H5O) 4Si, desublimata khoom (NH4) 2SiF6 nyob rau hauv gaseous daim ntawv raws li tau zoo raws li nyob rau hauv aqueous ammonia thiab cov aqueous lub ntsiab (tej zaum nrog rau qhov sib ntxiv ntawm cov organic bases, los yog ethanol).

amorphous silicon dioxide npaj kom txhij:

- diatomite thiab Tripoli;

- calcination mov husk;

- sib tsoo ntawm fused quartz.

Anhydrous silica hmoov yog ua:

- siv cov pa tshuaj deposition;

- los ntawm hydrolysis thiab oxidation vapor esters pyrogenic silica thiab silicon fluoride;

- los ntawm combustion ntawm silicon tetrachloride SiCl4 vapor nyob rau hauv ib tug sib tov ntawm H2 thiab O2.

Raws li siv silica?

- Ntuj silica siv nyob rau hauv qhuav ntawm iav, pob zeb ua, ntxhib no los txhuam, xuab zeb txiv qaub bricks, ceramics, earthenware, DINACYT, silicate tsom iav;

- Khoom cua silica ( "dawb carbon dub") yog siv raws li tub lim nyob rau hauv lub chaw ua khoom ntawm roj hmab;

- quartz ib muaju tau pom siv nyob rau hauv electronics (cov ntxaij lim dej, zaus stabilizers piezoelectric, resonators) nyob rau hauv acoustoelectronics thiab acousto, nyob rau hauv hniav nyiaj hniav kub, nyob rau hauv lub kho qhov muag ntsuas;

- rhinestone thiab hluavtaws pob zeb ntais dioxide yog siv raws li cov ntaub ntawv raw rau zus tau tej cov quartz iav, quartz, ib siv lead ua quartz fibers thiab tej hub. Nyob rau hauv lem, ceramics thiab quartz iav yog siv nyob rau hauv lub chaw ua dav hlua kev lag luam, optics, electronics thiab lwm yam lag luam. Quartz yog siv raws li ib tug ntaub khoom, Thaum tshav kub kub tuav, thiab quartz fibers - tsim muaj fiber ntau-optic lub nruab ntawm cov ntaub ntawv hloov lwm lub tsev thiab kev sib txuas lus kab.