Hafnium: daim ntawv thov thiab khoom

Taw qhia rau hauv tsab ntawv no yuav cia tus neeg nyeem nyeem kom paub seb qhov hnyuv (lub keeb tshuaj) yog, daim ntawv thov uas yog siv los ntawm cov txiv neej hauv ntau qhov chaw ntawm nws txoj haujlwm. Thiab tseem yog cov khoom ntawm cov tshuaj thiab lub cev ntawm lub cev, cov kev rho tawm thiab kev tshawb nrhiav hauv ntiaj chaw, cov keeb kwm luv luv ntawm qhov kev nrhiav tau ntawm cov no yuav raug suav hais tias yog.

Dab tsi yog hafnium

Hafnium yog ib hom tshuaj ntawm lub rooj thawm. Nws yog nyob rau hauv plaub pawg, lub thib rau lub sij hawm, lub cim naam yog xya caum-ob. Xa mus rau hom tshuaj yooj yim, muaj lub siab ceev thiab refractoriness, xim ntawm cov hlau yog silvery-dawb. Hafnium muaj peev xwm nyob hauv ob qho kev hloov kho. Nyob rau ntawm kev kub ntawm kev kub ntxhov ntawm xyoo 2016, Kelvin, lub lattice ntawm hom hexagonal, niaj kev hloov txhua qhov chaw, hloov mus rau hauv ib lub xeev ntawm lub cev ntawm lub cev nqaij daim tawv qis, nyob rau hauv chav tsev kub muaj ib tug siv lead ua ntxaij ntawm hexagonal syngony.

Los ntawm cov khoom nrhiav keeb kwm

Lub discovery ntawm lub caij tshwm sim nyob rau hauv 1923, ua los ntawm Gyorgy De Heshevi thiab Koster Dirk. Lawv tau twv seb qhov kev muaj nuj nqes thiab ntau yam zoo ntawm txoj kev ntxhov siab, raws li cov lus xaus ntawm N. Bohr, leej twg, tig los soj ntsuam txoj haujlwm ntawm Fabkis J. Urben, leej twg ntseeg tias nws nrhiav tau lub Celtic - ib qho tshiab. Txawm li cas los, nws muab tom qab tias qhov sib xyaw ntawm ib qho me me ntawm hafnium nrog lutecium thiab ytterbium yog Keltium.

Niels Bohr, kawm ua hauj lwm no thiab siv cov lus ua ntsuas me me, ua tim khawv tias txoj hlab ntsws yog ib qho piv txwv ntawm lub xov tooj 71 hauv PTCA, uas yog zirconium. Gyorgy De Heshevi thiab Koster Dirk tshaj tawm qhov kev paub ntawm ib qho tshiab ntawm hafnium, muaj npe tom qab lub nroog qhov chaw nrhiav tau, tom qab siv xais hluav taws xob spectral, zircons ntawm Norway thiab Greenland tau rov soj ntsuam dua. Tshawb nrhiav kev zoo sib xws ntawm cov kab xoo hluav taws xob pub cov kws tshawb fawb tau tshaj tawm cov kev tshawb nrhiav x-ray tshiab.

Txoj kev tau txais thiab ntiaj teb cov nyiaj

Hafnium yog nyob hauv daim tawv nqaij ntawm lub ntiaj teb, tab sis tsis muaj nws cov ntxhia, thiab yog li ntawd nws yog ib qho "satellite" ntawm zirconium. Tus nqi ntawm Hf nyob rau hauv ores yog kwv yees li 2.5%, thiab cov khoom noj txhua xyoo yog li txog xya caum tons. Hafnium yog ib qho khoom kim heev, nws qhov chaw tseem ceeb nyob hauv Australia, South Africa, Tebchaws Asmeskas, Is Nrias teb thiab Brazil. Qhov chaw ntawm lub teb chaws nyob rau hauv qhov kev txiav txim ntawm qhov hloov mus rau qhov chaw los ntawm tus naj npawb ntawm Hf nyob hauv lub teb chaws. Nws kuj yog tsim nyog hais txog tias Russia thiab Ukraine muaj lub pov haum loj loj ntawm cov hlau no, feem ntau ntawm cov uas muaj concentrated zirconium, loparite thiab baddeleyite.

Cov Cwj Pwm ntawm Lub Cev

Ib feem ntawm lub cev nqaij daim tawv cov khoom ntawm hafnium twb hais saum toj no. Koj tuaj yeem tau ntxiv rau lawv tias cov hlau no, uas, noj ib lub xeev uas muaj dispersed finely, yuav luag dub. Melts ntawm 2233 degrees Celsius, kub pib thaum 4603 ^C. ntoo khaub lig seem rau capture ntawm thermal neutrons yog heev hom. Zirconium, hauv qhov sib piv rau hafnium, muaj qhov seem ntawm tshooj uas yog peb txiav txim ntawm qhov loj tshaj. Thaum lub sij hawm tus capture ntawm Hf yog 115 tuav, nyob rau hauv zirconium nws tsuas yog li 0.2 bar. Hafnium muaj qhov sib npaug sib npaug ntawm cov kub ntawm germanium (Ge) thiab yog ib qho tseem ceeb. Lub zog ntawm lub cua sov yog ntawm qib 60-80 Kelvin. Qhov no tsis tuaj yeem piav qhia los ntawm txhua txoj kev xav txog Hooke rog, uas yog vim tsis muaj peev xwm ntawm Einstein superposition ua haujlwm kom muab ib tus qauv nrog qhov siab kawg.

Tshuaj lom neeg

Hafnium muaj x-fais fab tuaj yeem ua tau zoo dua qhov uas zoo ib yam zirconium. Qhov hlau nws tus kheej yog heev inert, uas yog txuam nrog ib zaj duab xis ntawm passive oxide uas yog tsim on hafnium. Nws yog qhov zoo tshaj rau dissolve Hf nyob rau hauv hydrofluoric acid, ib tug sib tov ntawm hydrofluoric acid nrog nitric acid thiab nyob rau hauv vaj ntxwv vodka. Thaum siab kub, nws Burns nyob rau hauv oxygen, thiab nyob rau hauv qhib cua pib oxidize. Muaj peev xwm nkag rau cov duab x-ray nrog halogens. Muaj cov khoom siv hydrophobic.

Ob chav ntawm ob-, peb- thiab plaub-ntsug Hf

Rau qhov no, qhov nqi ntawm kev muaj nqis yog txawv thiab, raws li qhov sib txawv ntawm qhov sib txawv ntawm qhov muaj x-ties, muaj ob peb qho tseem ceeb ntawm kev tiv thaiv ntawm lwm yam tshuaj.

Divalent hafnium dibromide muaj ib tsos xim ntsuab xim. Nyob rau ntawm qhov kub ntawm 400 degrees Celsius pib txheej txheem kho dua tshiab nrog Hf thiab HfBr4. Hauv kev lag luam, nws yog tsim los ntawm kev tsis pom zoo nyob rau hauv lub tshuab nqus tsev HfBr3 hauv thermal action.

Trivalent Hf yog sawv cev los ntawm tribromide (HfBr3) - cov khoom no yog xim dub-xiav, tsis muaj zog. Nyob rau hauv tus ntawm ib qhov sib npaug ntawm 400 degrees Celsius, nws pib disproportionate rau ob feem ntawm hafnium tetrabrombites thiab dibromobids. Txoj kev siv ntau hauv kev txo ntawm HfBr4 los ntawm cua sov hauv hydrogen, optionally nrog rau ntxiv ntawm txhuas.

Rau cov tebchaw ntawm tetravalent hafnium muaj ntau qhov zauv ntawm cov tebchaw, namely HfO2 yog nws cov dioxide, thiab tseem hydroxide nrog formula x-th Hf (OH) 4. Muaj cov tshuaj tertrachloride (HfCl4), tetrafluoride (HfF4), tetraiodide (HfI4) thiab saum toj no hais tias hafnium tetrabomide (HfBr), thiab tseem muaj cov thevnium hydrogenphosphates (Hf (HPO4) 2).

Daim ntawv thov nyob rau hauv txhua txhua hnub lub neej thiab kev sib txuas lus nrog cov tshuaj

Hafnium pom nws daim ntawv thov nyob rau hauv ib tug xov tooj ntawm cov fab ntawm kev ua si ntawm tib neeg haiv neeg. Qhov no yog vim muaj ntau ntau ntawm cov cwj pwm zoo, cov khoom uas ua rau nws yog ib qho khoom tseem ceeb, ib yam khoom hauv ntau hom neeg lag luam, kev ua tub rog thiab txawm nyob hauv nuclear kev lag luam.

Yog li cas siv hafnium? Daim ntawv thov hauv tshuaj - qhov no yog ib qho ntawm ntau txoj hauv kev uas koj tuaj yeem siv cov khoom ntawm cov hlau no. Vim tias Hf carbides yog cov dej num hnyav heev, siv cov khoom tsis muaj corrosive, lawv tuaj yeem siv los txiav cov khoom siv los ntawm cov kws kho mob, thiab lawv kuj tau siv los ua qhov kev tsim X-ray daim iav.

Ib lub caij nrog cov khoom tshwj xeeb ntawm ob qho tib si tshuaj thiab lub cev yog kev ntxhov siab. Daim ntawv thov nyob rau hauv lub neej txhua hnub, nws pom tau tias yog ib yam khoom nyob rau hauv lub chaw ua khoom ntawm xov tooj cua technology, xov tooj cua tubes thiab TV tubes. Nws yog dav siv nyob rau hauv kev lag luam metallurgical nrog aim ntawm ua lwm yam hlau ntawm zoo dua physicotechnical thiab mechanical zog. Hafnium kuj tseem siv xoo hluav taws xob, tab sis nws tsis tshua siv vim nws tsis muaj zog thiab ntau txoj hauv kev hauv daim ntawv thov.

Kev siv cov nyom hauv cov khoom siv tub rog

Koj siv tau lwm yam li cas? Kev siv hauv hauv riam phom yog lwm tus kheej ntawm tib neeg kev ua ub ua no, nyob rau hauv uas nws tsis ua yam tsis muaj qhov no. Oxides, silicides, borides thiab carbides of hafnium yog cov tshuaj tsis tshua muaj zog, vim li no hauv cov khoom siv tub rog lawv tuaj yeem raug siv los ua ib qho kev tiv thaiv. Nws tseem yog ultra-high-lub zog, uas ua rau nws siv tau Hf thiab nws cov tebchaw rau zus tau ntau qhov chaw los ntawm kev ua haujlwm rau huab-high-speed aircraft thiab rockets, nrog rau qhov chaw sawv daws.

Txij xyoo 1998, tau sim tau tsim los tsim ib lub "hafnium foob pob", raws li isomer 187m2Hf. Tab sis vim tias kev tshawb nrhiav thiab kev soj ntsuam, lub tswv yim ua kom tsis tsim nyog, qhov no yog vim tsis muaj peev xwm, nrog rau cov kev yees siv tam sim no, kom ua qhov tso tawm ntau tshaj zog los ntawm cov tub ntxhais ntawm no isomer.

Lwm cov kev siv ntawm cov khoom yooj yim Hf

Hauv nuclear fais fab, nrog rau saum toj-hais spheres, tab sis txawm nyob rau hauv ntau loj qhov ntau, hafnium kuj siv. Qhov hlau no siv nyob qhov twg? Vim tias nws muaj peev xwm neutron kev ntes ntawm Hf, qws rau kev tswj hwm, tshwj xeeb iav thiab ceramics.

Hafnium muaj ib qho kev ua tau zoo ntawm cov hluav taws xob hauv hluav taws xob (3.53 eV) thiab vim li no nws tuaj yeem raug siv hauv cov cathodes thiab electron phom ntau lawm. Hauv nuclear reactive roj-theem xyaw, nws yog ib qho ua tau nrhiav cov ntxhuav thiab carbides ntawm hafnium, los yog nyob rau hauv qee yam ntawm cov qauv ua.

Hafnium yog siv txawm nyob rau hauv lub chaw ua khoom ntawm thermoelectric hom generators thiab feem ntau pom nyob rau hauv ionic xyaw. Rau ntawm HfO2, dielectrics nrog ib theem siab ntawm permittivity yog tsim. Nyob rau hauv lub neej yav tom ntej, nws yog npaj los hloov cov paub zoo silicon oxide hauv microelectronics nrog HfO2 oxide. Qhov kev hloov no yuav ua rau kom muaj qhov sib txawv hauv cov nti.

Nyob rau hauv xaus, peb yuav hais tias hafnium, daim ntawv thov ntawm uas yuav siv qhov chaw nyob rau hauv ntau ceg ntawm tib neeg kev ua si, pib txhua txhua hnub thiab xaus nrog tub rog thiab atomic, yog ib qho tseem ceeb heev lub caij. Qhov no yog ib qho hlau uas xav tau thiab ib txwm nrog accompanies zirconium. Cov rarity thiab nws cov yam ntxwv ntawm cov yam ntxwv muaj txiaj ntsig ua rau ib tus nqi siab.