Lub sab muaj coob ntawm molybdenum yog siv nyob qhov twg, zog, lom luag hauj lwm nyob rau hauv tib neeg lub cev

Science News for KIDS yog lub hauv paus ntawm peb lub neej. Tag nrho tsev neeg cov khoom yog ua los ntawm periodic rooj ntsiab sib txuas. Txhua feeb nyob rau hauv tib neeg niaj complex transformations uas tshuaj. Nyob rau hauv no tsab xov xwm koj yuav kawm txog ib tug hlau xws li molybdenum qhov uas siv tau, nws cov khoom thiab lub luag hauj lwm nyob rau hauv tib neeg lub cev.

Peb delve rau hauv keeb kwm

Minerals muaj nyob rau hauv nws muaj pes tsawg leeg ntawm molybdenum, twb paub nyob rau hauv ancient Greece. Cov ntuj tebchaw muaj ib tug qauv zoo li graphite. Yog li ntawd nws yog feem ntau siv nrog nws los ua ib tug lead. Molybdenite MoS₂ muaj gray-ntsuab zas thaum uas sau ntawv rau ntawm daim ntawv. Cov yam ntxwv ci molybdaena nws lub npe tau muab - "zoo li cov hlau lead."

Carl Wilhelm Scheele researched los ntawm uas nws tsim trioxide MoO₃, tab sis vim yog cov tsis muaj kev tsim nyog cub tawg yog tsis tau rov qab tau cov hlau nyob hauv cov ntshiab daim ntawv. Yonsu Jakob Berzelius ua tau zoo nyob rau hauv 1817 xyoo kom tau molybdenum oxide rov qab los ntawm tsis muaj thee thiab hydrogen. Synthetic caij tau ua tib zoo kawm thiab tau piav nyob rau hauv tej hauj lwm ntawm tus paub txog.

lub zog

Yuav ua li cas yog molybdenum? Qhov no lub teeb grey hlau uas nyob rau hauv nws cov ntshiab daim ntawv no yog resistant rau oxidation (nyob rau hauv ib txwm tej yam kev mob). Nrog kub nce mus 400-600 degrees, qhov no muaj peev xwm txo thiab tsim trioxide MoO₃.

Molybdenum kovok zas thiab nkag undergoes forging. Hlau Ceev 10.2 g / ^cm3, melting point 2620 ⁰S boiling - 4800 ⁰S. Los ntawm cov nuj nqis nws yog tseeb hais tias nws yog heev tugoplavok. Lub xub ntiag ntawm cov pa roj carbon, nitrogen los yog leej faj impurities cuam tshuam rau lub zog, nyob rau hauv particular, cov khoom yuav taus thiab nkig. Molybdenum yog paramagnetic. Nrog nce nws kub zog yog heev zog.

Ntuj molybdenum compound, muab

Nws yuav tsum tau paub hais tias molybdenum yog tsis pom nyob rau hauv cov ntshiab daim ntawv no, nws yog tam sim no nyob rau hauv cov xwm xwb nyob rau hauv lub tebchaw nrog rau lwm cov ntsiab. Zoo Heev hlau cov ntsiab lus nyob rau hauv lub kiav txhab 3 ∙ 10 ^-4%. Muaj txog 15 minerals, ntawm uas feem ntau yog:

• disulfide hlis ₂ - molybdenite;
• CaMoO ₄ - powellite;
• PbMoO ₄ - wulfenite.

Main teb ntawm cov tebchaw yog ze ze nrog cov txheej txheem ntawm deposition nyob rau hauv hydrothermal qhov chaw.

Nyob rau hauv industrial hom phiaj yog muab rho tawm molybdenum disulfide caij. Nws daim ntawv thov yog qho tseem ceeb heev rau muab ntshiab hlau. Qhov no tshwm sim los ntawm txoj kev kawm ntawm ores los ntawm flotation. Yog li tau concentrate, uas yog tom qab raug calcination.

2MoS ₂ + 7O ₂ = 2MoO ₃ + 4SO ₂

Ib tug raug rho tawm thiab lim oxide yog txo nrog qhuav hydrogen kwj ntawm ib tug kub ntawm 700 degrees. Cov tshuaj tiv thaiv cov khoom no yog ib tug hmoov ntawm molybdenum. Nyob rau hauv lub neej yav tom ntej tej zaum nws yuav tsum siv nyob hauv cov ntshiab daim ntawv los yog raws li ib tug cov ntaub ntawv uas rau constituting tus ntxuag thiab molded cov khoom.

Qhuav ntawm alloy steel

Ferrous metallurgy siv molybdenum hmoov substance. Qhov twg yog nws siv? Rau alloying steels thiab cam khwb cia irons. Tsis tas li ntawd ntawm no nyob rau hauv lub alloys tshuam pab lawv zoo. Nce elasticity, puas kuj, tej yam kuj. Cov yam ntxwv steel ntxiv hais txog 0.5% molybdenum, zoo grain yuav ntau yam thiab los ntawm no lawv cov qauv, txo brittleness kawg khoom.

Qhov sib ntxiv ntawm lwm yam tso cai rau kom muab tau tshwj xeeb compositions yog lug siv nyob rau hauv ntau yam industries. Alloys, uas muaj xws li cobalt thiab npib tsib xee (50-60%) thiab chromium (kwv yees li 20-28%) yog doped los ntawm kev ntxiv molybdenum. Qhov twg tej khoom siv? Cov lus teb cov lus dag nyob rau hauv nws cov khoom tshwj xeeb - kub siab kuj. Nws yog siv nyob rau hauv qhov siv thiab ua aircraft qhov chaw thiab missile casing.

Siv alloys nrog molybdenum

Los ntawm kev ntxiv molybdenum rau niobium, titanium, thiab lwm yam co tsub kom ultra tshav kub kuj hlau. Qhov no muaj pes tsawg leeg yuav siv tau los tsim qhov chaw ntawm roj turbines thiab combustion lag nyob rau hauv foob pob ua ntxaij.

Nyob rau hauv lub alloys nrog ib tug loj npaum li cas ntawm molybdenum (17-28%) nce xeb kuj. Lawv tsis txawm ntshai kev sis raug zoo nrog rau tej acid (tsuas yog HF).

Lub refractory thaj chaw ntawm molybdenum thiab nws siv nyob rau hauv kev tsim tshwj xeeb kav yog ntawm kuj zoo kawg tseem ceeb nyob rau hauv lub nuclear fais fab kev lag luam. Tej khoom muaj peev xwm ntawm tiv molten lithium. Nws ua lub luag hauj lwm ntawm lub coolant nyob rau hauv uranium reactors. Dhau li ntawd, lub molybdenum nyob rau hauv ib tug Mo-99 isotope pom daim ntawv thov raws li ib tug qhia nyob rau hauv lub nuclear kev lag luam.

Vim infusibility molybdenum therefrom tsim pwm rau casting qhov chaw ua los ntawm tooj liab, txhuas thiab zinc. Lub siab lub dag lub zog hlau enables muaj dab nyob hauv siab siab.

Ntiav thiab xuas nrig ntaus, daim ntawv thov

Los ntawm teb tau los ntawm melting cov hmoov, ua dov khoom - rods thiab hlau. Lawv muaj xws li ib tug dawb huv hlau molybdenum cai. Qhov twg tej khoom yuav siv? Feem ntau cov feem ntau nws yog siv nyob rau hauv qhov siv thiab ua thermocouples uas yog siv rau cov ntsuas kub saum toj no 2000 ⁰C. Hooks thiab cores rau winding tungsten filament nyob rau hauv ib tug incandescent teeb no kuj ua los ntawm molybdenum hlau. Zoo ntawm lub cathodes thiab lub tsom electrodes nyob rau hauv lub X-ray hlab thiab generating hlab yuav tsum txhim khu kev qha thiab raws li yuav tsum tau ntawm siab refractory hlau. Rau cov hom phiaj, paug suited molybdenum sis.

Rods thiab daim hlau yog siv nyob rau hauv qhov chaw ntawm electrodes nyob rau hauv lub high-melting furnaces. Lawv yuav tsum tau muab tso rau hauv ib tug tshwj xeeb nruab nrab muaj argon, hydrogen, los yog tshuab nqus tsev. Vim lub fact tias molybdenum tsis nkag rau hauv lub khob nyob rau hauv tshuaj tshua, nws yog thov rau manufacturing chaw melter.

Daim ntaub ntawv nyob rau hauv lwm yam lag luam

Molybdenum tau pom daim ntawv thov nyob rau hauv cov roj kev lag luam. Nws muaj nws yog siv raws li ib lub hauv paus tau purify cov khoom los ntawm cov leej faj impurities. Aluminium-raws li lubricants manufactured disulfide. Lawv tswj lub lag luam los ntawm ntau yam pab kiag li lawm thiab tiv thaiv qhov chaw tiv thaiv txhua yam kev puas tsuaj nyob rau high school kub. Nws muaj xws li ib tug roj nplua nyeem thiab anticorrosive zog.

Nyob rau hauv lub chaw ua khoom ntawm cov xim tsev, qhov twg nws yog ua ntawv thov thiab molybdenum oxides, tau pigments pheej daj-txiv kab ntxwv ntxoov. Synthesis ntawm lub dag fibers kuj kis tsis muaj tus substance. Nyob rau hauv thiaj li yuav ua rau kom cov nitrogen cov ntsiab lus ntawm cov av siv microfertilizer, uas muaj xws li molybdenum.

Lub luag hauj lwm ntawm molybdenum nyob rau hauv lub cev

Molybdenum yog muab ib qho tseem ceeb luag hauj lwm nyob rau hauv tib neeg lub cev. Nws yog kev koom tes nyob rau hauv lub synthesis ntawm hemoglobin, nitrogen thiab purine metabolism. Yog lub luag hauj lwm rau qhov haum ntawm cov iron thiab vitamin C, ib tug haib antioxidant. Microelement muaj onkoprotektornyh, rejuvenating nyhuv.

Cov khoom noj uas nplua nuj nyob rau hauv molybdenum - yog legumes thiab cereals, pom zaub. Qhov yuav tsum tau npaum li cas ntawm txoj lw caij nkag mus rau hauv lub cev nyob rau txhua hnub, yog tias koj noj txoj cai. Nws tsis muaj peev xwm yuav tau sau siv mineral ceg.