Ib tug neeg zoo tib yam uas tsis cuam tshuam nrog chemistry thiab tshuaj, raws li txoj cai, muaj lub tswv yim tsis meej txog qhov tseem ceeb ntawm cob alt rau nws lub neej thiab kev noj qab haus huv. Lwm qhov laj thawj vim li cas peb pom tias nws nyuaj rau piav qhia tias cob alt yog dab tsi yog nws qhov tsis tshua muaj kev faib tawm hauv qhov xwm txheej. Tsuas yog 0.004% - qhov no yog nws cov ntsiab lus nyob rau hauv lub ntiaj teb crust. Txawm li cas los xij, cov hlau thiab nws cov tebchaw yog nquag siv hauv metallurgy, kev ua liaj ua teb thiab tshuaj. Hauv peb tsab xov xwm, peb yuav nthuav peb txoj kev nkag siab txog lub luag haujlwm ntawm cob alt hauv kev lag luam, nrog rau kev nyob ntawm nws txoj haujlwm hauv tib neeg lub cev.
Qhov chaw ntawm lub ntsiab lus hauv Lub Sijhawm Sijhawm
Qhov chaw twg cob alt nyob hauv lub sijhawm? Cov khoom ntawm cov khoom siv tshuaj, suav nrog cov hlau peb tab tom xav, nyob ntawm lawv txoj haujlwm hauv lub rooj ntawm D. I. Mendeleev. Nws nyob hauv pawg VIII b (hauv daim ntawv luv luv ntawm lub rooj - hauv cov hlau triad ntawm pawg VIII). Zoo li hlau thiab npib tsib xee, hauv nws cov atom ntawm lub zog kawg yogob lub electrons, uas qhia tau hais tias cov hlau belongs rau d-cov ntsiab lus thiab txiav txim siab nws cov yam ntxwv tseem ceeb. Cov hlau muaj ob valences - II thiab III. Nws kuj yog tus cwj pwm los ntawm qhov tshwm sim ntawm allotropy, kev hloov kho hlau tuaj yeem muaj cov qauv cubic lossis hexagonal.
cob alt yog dab tsi?
Dab tsi yog lub zog ntawm lub cev? Nyob rau hauv tsos, nws yog ib tug hlau nrog siab hardness thiab magnetic zog. Silvery sheen, malleability thiab thermal stability yog ib co ntawm lub cev nta ntawm lub caij, uas kuj muaj nyob rau hauv nws ob tug lwm tus neeg nyob ze nyob rau hauv lub periodic system - npib tsib xee thiab hlau. Tsis muaj oxygen lossis dej ua rau cob alt ntawm qhov kub thiab txias. Nws cov tebchaw, xws li sm alt, tau ntev tau paub tias yog cov khoom siv los tsim cov iav xiav thiab xim ceramics.
Cob alt yog cov hlau zoo ib yam hauv cov khoom siv tshuaj rau hlau. Dab tsi yog cov yam ntxwv ntawm nws cov oxides, hauv paus thiab ntsev?
Cov sib xyaw ntawm divalent thiab trivalent cob alt
Lub peev xwm los tsim cov ntsev nyuaj yog qhov tseem ceeb ntawm Co (III) atoms. Cov tshuaj no tsis ruaj khov, kev sib koom tes ntawm cob alt hauv lawv ib txwm sib npaug rau rau. Lawv muaj lub zog oxidizing siab. Cov ntsev nruab nrab, xws li CoCL3 lossis Co2(SO4)3 tau yooj yim hloov mus rau hauv ntsev, uas cob alt twb yog hlau divalent. Nws cov anhydrous compounds muaj xim xiav, thiab crystalline hydrates thiab daws -liab. Tsis zoo li lwm cov hauv paus, trivalent cob alt hydroxide, thaum cuam tshuam nrog hydrochloric acid, tsis tsim ntsev thiab dej, tab sis tso tawm dawb chlorine los ntawm nws. Lub hauv paus ntawm divalent hlau nyob rau hauv daim ntawv ntawm ib tug xiav precipitate yog tau los ntawm ncaj qha cov tshuaj tiv thaiv ntawm coj ntsev nrog ib tug alkali. Cia peb muab cov lus piav qhia ntawm cov khoom ntawm cob alt, uas yog ib feem ntawm cov ntsiab lus ntawm cov hlau hauv ib leeg - alloys.
Nws muab cov khoom tshwj xeeb ntawm kev ntsuas kub tsis kam, hardness, puas thiab corrosion kuj. Alloys uas muaj cob alt yog siv nyob rau hauv kev lag luam tiv thaiv, foob pob ua ntxaij science thiab nyob rau hauv kaw-voj chemistry. Hauv kev tsim cov cuab yeej qib ntawm cov hlau, cov khoom siv nrog cov khoom sib nqus, cob alt kuj yog siv los ua cov khoom siv ntxiv. Cov khoom ntawm cov hlau alloys no txawv heev ntawm cov pa stainless hlau uas tsuas muaj chromium los yog npib tsib xee.
Kev siv cob alt hauv engineering
Raws li ib feem peb ntawm tag nrho cov hlau uas tsim nyob rau hauv lub ntiaj teb no mus rau zus tau tej cov cermets - cov khoom siv dag zog. tungsten carbide ua lub hauv paus ruaj khov nyob rau hauv lawv, thiab cob alt ua raws li kev khi thiab kho cov khoom. Nws tseem yog cov khoom siv raw khoom siv rau kev tsim cov cav turbines hauv kev lag luam dav hlau.
Hauv nws daim ntawv ntshiab, cov hlau tsis siv, tab sis kev siv cob alt hauv kev sib xyaw nrog lwm cov ntsiab lus (hlau, tooj liab, tungsten thiab chromium) yog dav hauv ntau yam.kev lag luam. Lub stellite alloy, muaj txog li 60% cob alt, yog tus cwj pwm los ntawm kev ua kom sov thiab hardness; nws yog ib qho khoom siv tseem ceeb rau kev tsim cov cutters thiab xyaum hauv cov cuab yeej tsim khoom. Alloying ntsiab xws li tungsten thiab molybdenum txhim khu nws kev ua tau zoo. Vitalium alloy, uas muaj kev tiv thaiv siab rau cov yas deformation, kuj muaj cob alt. Cov yam ntxwv ntawm cov khoom ntawm lub compound yog raws li nram no: tshav kub-resistant thiab acid-resistant, nws yog siv nyob rau hauv lub tsim ntawm cov khoom siv tshuaj: synthesis kab, distillation apparatus. Lub luag hauj lwm ntawm alloys nyob rau hauv counteracting ntau yam corrosion yog zoo, piv txwv li, qhov chaw thiab mechanisms ua los ntawm stellite tiv thaiv kev puas tsuaj thaum lub sij hawm oscillatory thiab rubbing txav ntawm cov neeg kho tshuab nto nyob rau hauv lub internal combustion engines.
Txoj kev kom tau txais cob alt
Txoj haujlwm sib txawv ntawm kev lag luam yuav tsum siv cov khoom siv cob alt. Qhov no ua rau muaj kev nce ntxiv hauv kev rho tawm ntawm ores thiab cov zaub mov, uas yog: cob alt txuj lom thiab gloss. Cov muaj pes tsawg leeg ntawm cov pob zeb no kuj suav nrog arsenic, uas yuam kev siv cov kev ntsuas kev nyab xeeb ntxiv hauv cov txheej txheem ntawm cov hlau smelting. Txoj kev tseem ceeb ntawm kev tau txais cob alt yog pyrometallurgy, thiab txoj kev kho cov ore nrog sulfate acid kuj siv. Qhov zoo tshaj plaws yog cov deposits ntawm silicate-oxide ores, pyrite thiab pentlandite nyob rau hauv Tuam Tshoj, Russia (nyob rau hauv lub Kola ceg av qab teb, nyob rau hauv lub koom pheej ntawm Tuva thiab lub Krasnoyarsk Territory), raws li zoo raws li nyob rau hauv Canada.
Kev siv hlau hauv kev ua liaj ua teb thiabtshuaj
Qee yam khoom tseem ceeb ntawm cov kab mob cob alt pab txhawb rau nws txoj kev siv, piv txwv li, hauv kev tsim qoob loo kom nce cov qoob loo ntawm cov nroj tsuag. Nyob rau hauv alfalfa, lupine, clover thiab lwm yam muaj txiaj ntsig nyom nyom ntawm tsev neeg legume, nws muaj nyob rau hauv cov tshuaj tiv thaiv enzymatic ntawm nitrogen fixation, uas tshwm sim nrog kev pab los ntawm cov kab mob nodule. Qhov tsis muaj microelement yog tshwm sim los ntawm cov tsos mob xws li kev hloov pauv ntawm nplooj nplooj thiab lawv tsis muaj peev xwm mus rau photosynthesis, slowing down txoj kev loj hlob thiab cuam tshuam ntawm tag nrho cov nroj tsuag kev loj hlob voj voog. Cov ntsiab lus ntau dhau ntawm cob alt tuaj yeem ua tau vim yog kev ua txhaum cai ntawm kev qhia txog microfertilizers. Txij li thaum nws cov tebchaw yog soluble nyob rau hauv dej, lawv tam sim ntawd nkag mus rau xylem thiab los ntawm cov conductive ntsiab (vascular-fibrous bundles) nkag mus rau hauv nplooj mesophyll, ua rau lawv discoloration thiab wilting. Cereal qoob loo yog rhiab heev rau ntau tshaj ntawm microelement: oats, barley, mov.
Biochemistry txog lub luag haujlwm ntawm cob alt compounds
Cov ceg ntawm biology uas kawm txog cov teeb meem nyob hauv qib molecular thiab cellular tau tsim cov haujlwm tseem ceeb ntawm cov tshuaj no. Nws yog ib feem ntawm cov uas tsis yog-protein ib feem ntawm biologically active tshuaj - enzymes thiab cov tshuaj hormones. Piv txwv li, cob alt nyob rau hauv tib neeg lub cev muaj nyob rau hauv thyroxine molecules tsim los ntawm cov thyroid caj pas thiab tswj cov txheej txheem metabolic. Lwm qhov tseem ceeb ntawm cov tshuaj hormones uas tswj cov ntshav qabzib yog insulin. Nws yog secreted los ntawm β-hlwb ntawm cov islets ntawm Langerhans ntawm lub txiav thiab kuj muaj cob alt tebchaw. Kev muab khoom tsis txausCov ntsiab lus hauv tib neeg lub hlwb thiab cov kabmob yog pom thaum lub sijhawm hloov pauv ntawm kev noj zaub mov sib xyaw rau cov neeg tsis noj nqaij, nrog helminthic invasions thiab kab mob ntawm lub plab zom mov. Raws li koj tuaj yeem pom, cob alt yog ib qho kab mob uas cuam tshuam rau qib ntawm homeostasis hauv tib neeg lub cev.
Y Qhov tseem ceeb ntawm cov tshuaj lom neeg hauv cov metabolism
Hematopoiesis, nqa los ntawm cov pob txha liab, tshwm sim nrog kev koom tes ntawm cob alt-muaj tshuaj - activators ntawm cov enzymes sib xws. Ib qho ntawm cov vitamins B tseem ceeb - cyanocobolamin (B 12), koom nrog tsim cov qe ntshav liab hauv cov kab mob hematopoietic, tiv thaiv lub cev los ntawm ntshav ntshav. Khoom noj khoom haus kom zoo thiab sib npaug, muaj lub siab, nqaij nyuj, nqaij nruab deg, qhuav apricots, beets, yuav muab cov qib cob alt tsim nyog hauv tib neeg lub cev (li 40 mg ib hnub twg) thiab tiv thaiv nws los ntawm cov kab mob ntawm lub cev tiv thaiv kab mob, kab mob plawv thiab endocrine.
