Cov kab lus qhia txog thaum twg muaj cov tshuaj lom neeg xws li uranium tau tshawb pom, thiab nyob rau hauv kev lag luam uas cov tshuaj no tau siv nyob rau hauv peb lub sijhawm.
Uranium yog cov khoom siv tshuaj hauv lub zog thiab kev lag luam tub rog
Txhua lub sijhawm, tib neeg tau sim nrhiav cov khoom siv hluav taws xob muaj txiaj ntsig zoo, thiab qhov zoo - los tsim lub tshuab hu ua perpetual motion. Hmoov tsis zoo, qhov ua tsis tau ntawm nws lub neej yog qhov ua tau pov thawj thiab ua pov thawj rov qab rau xyoo 19th, tab sis cov kws tshawb fawb tseem tsis tau poob kev cia siab ntawm kev paub txog kev npau suav ntawm qee yam khoom siv uas yuav muaj peev xwm tsim tau ntau lub zog "huv" rau lub zog heev. ntev.
Ib feem ntawm qhov no tau pom nrog kev tshawb pom ntawm cov khoom xws li uranium. Cov khoom siv tshuaj lom neeg nrog lub npe no tsim lub hauv paus rau kev txhim kho cov tshuab hluav taws xob nuclear, uas nyob rau hauv peb lub sij hawm muab lub zog rau tag nrho cov nroog, submarines, nkoj polar, thiab lwm yam. Muaj tseeb tiag, lawv lub zog tsis tuaj yeem hu ua "huv", tab sis nyob rau xyoo tas los no ntau lub tuam txhab tau tsim cov khoom siv tritium-based "atomic batteries" rau kev muag dav - lawv tsis muaj qhov txav mus los thiab muaj kev nyab xeeb rau kev noj qab haus huv.
Txawm li cas los xij, hauv kab lus no peb yuav txheeb xyuas kom meej txog keeb kwm ntawm kev tshawb pom ntawm cov tshuaj lom neeghu ua uranium thiab cov tshuaj tiv thaiv ntawm fission ntawm nws cov nuclei.
Definition
Uranium yog cov khoom siv tshuaj lom neeg uas muaj atomic naj npawb 92 nyob rau hauv lub sij hawm ntawm Mendeleev. Nws cov atomic loj yog 238.029. Nws yog tsim los ntawm lub cim U. Nyob rau hauv ib txwm muaj mob, nws yog ib tug tuab, hnyav silvery hlau. Yog tias peb tham txog nws cov xov tooj cua, ces uranium nws tus kheej yog ib qho khoom siv hluav taws xob tsis muaj zog. Nws kuj tsis muaj cov isotopes ruaj khov kiag li. Thiab qhov ruaj khov tshaj plaws ntawm cov isotopes uas twb muaj lawm yog uranium-338.
Peb paub tias lub ntsiab lus no yog dab tsi, thiab tam sim no cia peb saib keeb kwm ntawm nws qhov kev tshawb pom.
History
Cov khoom xws li ntuj uranium oxide tau paub rau tib neeg txij li thaum ub, thiab cov neeg ua haujlwm qub siv nws los ua glaze, uas yog siv los npog ntau yam ceramics rau dej tsis kam ntawm cov hlab ntsha thiab lwm yam khoom, nrog rau lawv. decorations.
Xyoo 1789 yog hnub tseem ceeb hauv keeb kwm ntawm kev tshawb pom ntawm cov tshuaj no. Nws yog thaum ntawd tus kws tshuaj thiab German-yug Martin Klaproth tau txais thawj cov hlau uranium. Thiab lub caij tshiab tau txais nws lub npe nyob rau hauv kev hwm ntawm lub ntiaj teb nrhiav pom yim xyoo dhau los.
Rau yuav luag 50 xyoo, uranium tau txais tom qab ntawd suav tias yog cov hlau ntshiab, txawm li cas los xij, xyoo 1840, kws tshuaj los ntawm Fabkis, Eugene-Melchior Peligot, muaj peev xwm ua pov thawj tias cov khoom tau txais los ntawm Klaproth, txawm tias tsim nyog rau sab nraud., tsis yog hlau kiag li, tab sis uranium oxide. Ib me ntsis tom qab, tib lub Peligo tau txaistiag tiag uranium yog ib tug hnyav grey hlau. Nws yog ces hais tias qhov hnyav atomic ntawm xws li ib yam khoom xws li uranium yog thawj zaug txiav txim. Cov tshuaj nyob rau hauv 1874 tau muab tso rau Dmitri Mendeleev nyob rau hauv nws nto moo lub sij hawm lub ntsiab lus, thiab Mendeleev muab ob npaug rau atomic hnyav ntawm cov khoom. Thiab tsuas yog 12 xyoo tom qab, nws tau sim ua pov thawj tias tus kws tshuaj zoo tshaj plaws tsis tau yuam kev hauv nws qhov kev suav.
Radioactivity
Tab sis qhov kev txaus siab thoob plaws hauv lub ntsiab lus no hauv zej zog kev tshawb fawb tau pib xyoo 1896, thaum Becquerel pom qhov tseeb tias uranium emits rays uas muaj npe tom qab tus kws tshawb fawb - Becquerel rays. Tom qab ntawd, ib tus kws tshawb fawb nto moo tshaj plaws hauv daim teb no, Marie Curie, hu ua qhov tshwm sim ntawm xov tooj cua.
Hnub tseem ceeb tom ntej hauv kev tshawb fawb ntawm uranium yog suav tias yog xyoo 1899: nws yog thaum ntawd Rutherford pom tias cov hluav taws xob ntawm uranium tsis sib xws thiab muab faib ua ob hom - alpha thiab beta rays. Thiab ib xyoos tom qab, Paul Villar (Villard) tau tshawb pom qhov thib peb, yam kawg ntawm cov hluav taws xob hluav taws xob uas peb paub niaj hnub no - lub npe hu ua gamma rays.
Xya xyoo tom qab, xyoo 1906, Rutherford, raws li nws txoj kev xav ntawm radioactivity, ua thawj qhov kev sim, lub hom phiaj ntawm kev txiav txim siab hnub nyoog ntawm ntau yam minerals. Cov kev tshawb fawb no tau tsim lub hauv paus, thiab lwm yam, rau kev tsim cov kev xav thiab kev coj ua ntawm kev tsom xam radiocarbon.
Fission ntawm uranium nuclei
Tab sis, tej zaum, qhov kev tshawb pom tseem ceeb tshaj plaws, ua tsaug rau qhov uasKev nthuav dav mining thiab enrichment ntawm uranium rau ob qho tib si kev thaj yeeb thiab kev ua tub rog yog cov txheej txheem ntawm fission ntawm uranium nuclei. Nws tshwm sim xyoo 1938, qhov kev tshawb pom tau ua los ntawm German physicists Otto Hahn thiab Fritz Strassmann. Tom qab ntawd, qhov kev xav no tau txais kev pom zoo ntawm kev tshawb fawb hauv kev ua haujlwm ntawm ntau tus kws tshawb fawb German ntxiv.
Lub ntsiab ntawm cov txheej txheem uas lawv pom tau muaj raws li hauv qab no: yog tias koj irradiate lub nucleus ntawm uranium-235 isotope nrog ib tug neutron, ces, ntes ib tug dawb neutron, nws pib faib. Thiab, raws li peb txhua tus paub tam sim no, cov txheej txheem no yog nrog los ntawm kev tso tawm ntawm lub zog loj heev. Qhov no tshwm sim tsuas yog vim lub zog kinetic ntawm cov hluav taws xob nws tus kheej thiab cov tawg ntawm cov nucleus. Tam sim no peb paub yuav ua li cas uranium fission tshwm sim.
Qhov kev tshawb pom ntawm lub tshuab no thiab nws cov txiaj ntsig yog qhov pib ntawm kev siv uranium rau kev thaj yeeb thiab kev ua tub rog.
Yog tias peb tham txog nws siv rau kev ua tub rog, thawj zaug qhov kev xav tias nws muaj peev xwm los tsim cov xwm txheej rau cov txheej txheem xws li kev sib txuas txuas ntxiv ntawm cov uranium nucleus (vim tias lub zog loj yuav tsum tau tawg. nuclear foob pob) tau pov thawj los ntawm Soviet physicists Zeldovich thiab Khariton. Tab sis txhawm rau tsim cov tshuaj tiv thaiv zoo li no, uranium yuav tsum tau ua kom muaj txiaj ntsig zoo, txij li hauv nws lub xeev ib txwm nws tsis muaj cov khoom tsim nyog.
Peb tau paub keeb kwm ntawm lub caij no, tam sim no peb yuav txheeb xyuas qhov twg nws siv.
Uranium isotope siv thiab hom
Tom qab kev tshawb pom ntawm cov txheej txheem xws li uranium saw fission cov tshuaj tiv thaiv, cov kws kho mob tau ntsib cov lus nug ntawm qhov twg siv nws?
Tam sim no, muaj ob qhov chaw tseem ceeb uas siv uranium isotopes. Qhov no yog kev thaj yeeb (los yog lub zog) kev lag luam thiab tub rog. Ob qho tib si thawj thiab thib ob siv cov tshuaj tiv thaiv nuclear fission ntawm uranium-235 isotope, tsuas yog cov zis hluav taws xob sib txawv. Yooj yim muab tso rau hauv lub tshuab hluav taws xob nuclear, tsis tas yuav tsim thiab tswj cov txheej txheem no nrog tib lub zog uas tsim nyog los ua kom tawg ntawm lub foob pob nuclear.
Yog li, cov kev lag luam tseem ceeb uas siv cov tshuaj tiv thaiv uranium fission tau teev tseg.
Tab sis tau txais cov uranium-235 isotope yog ib txoj haujlwm nyuaj heev thiab kim heev, thiab tsis yog txhua lub xeev muaj peev xwm them taus los tsim cov nroj tsuag ntxiv. Piv txwv li, kom tau nees nkaum tons ntawm uranium roj, uas cov ntsiab lus ntawm uranium 235 isotope yuav yog los ntawm 3-5%, nws yuav tsum tau enrich ntau tshaj 153 tons ntawm ntuj, "raw" uranium.
Lub uranium-238 isotope feem ntau yog siv los tsim cov riam phom nuclear los ua kom lawv lub zog. Tsis tas li ntawd, thaum nws ntes cov neutron, ua raws li cov txheej txheem beta lwj, cov isotope no tuaj yeem hloov mus ua plutonium-239 - ib qho roj rau feem ntau niaj hnub nuclear reactors.
Txawm hais tias tag nrho cov kev tsis txaus ntawm cov reactors (tus nqi siab, kev tu vaj tu tsev, kev nyab xeeb ntawm kev sib tsoo), lawv cov haujlwm them sai sai, thiab lawv tsim lub zog ntau dua li cov nroj tsuag thermal lossis hydroelectric zog.
Tsis tas li, cov tshuaj tiv thaiv ntawm fission ntawm uranium nucleus ua rau nws muaj peev xwm tsim tau riam phom nuclear ntawm kev puas tsuaj loj. Nws yog qhov txawv los ntawm nws lub zog loj, txheeb zecompactness thiab qhov tseeb tias nws muaj peev xwm ua rau thaj tsam loj ntawm thaj av tsis haum rau tib neeg kev nyob. Muaj tseeb, niaj hnub riam phom atomic siv plutonium, tsis yog uranium.
Depleted uranium
Tseem muaj ntau yam ntawm uranium li depleted. Nws muaj cov xov tooj cua tsawg heev, uas txhais tau hais tias nws tsis txaus ntshai rau tib neeg. Nws yog siv dua nyob rau hauv cov tub rog, piv txwv li, nws yog ntxiv rau lub armor ntawm American Abrams tank muab nws ntxiv zog. Tsis tas li ntawd, nyob rau hauv yuav luag tag nrho cov tub rog high-tech koj tuaj yeem pom ntau lub plhaub nrog uranium depleted. Ntxiv nrog rau lawv cov huab hwm coj loj, lawv muaj lwm yam khoom muaj txiaj ntsig zoo - tom qab kev puas tsuaj ntawm qhov projectile, nws cov fragments thiab hlau plua plav ignite spontaneously. Thiab los ntawm txoj kev, thawj zaug xws li projectile tau siv thaum Tsov Rog Ntiaj Teb Zaum Ob. Raws li peb tuaj yeem pom, uranium yog ib qho khoom siv uas tau siv rau ntau yam kev ua haujlwm ntawm tib neeg.
Zoo kawg
Raws li cov kws tshawb fawb kwv yees, nyob ib ncig ntawm 2030, tag nrho cov uranium deposits loj yuav tsum tau depleted, tom qab uas txoj kev loj hlob ntawm nws nyuaj-rau-mus txog txheej yuav pib thiab tus nqi yuav nce. Los ntawm txoj kev, uranium ore nws tus kheej yog qhov tsis muaj teeb meem rau tib neeg - qee cov miners tau ua haujlwm ntawm nws cov extraction rau ntau tiam neeg. Tam sim no peb tau txheeb xyuas keeb kwm ntawm kev tshawb pom ntawm cov tshuaj no thiab yuav ua li cas cov tshuaj tiv thaiv fission ntawm nws cov nuclei siv.
Los ntawm txoj kev, qhov tseeb nthuav yog paub - uranium tebchaw tau ntev tau siv los ua xim rau cov plooj (porcelain) thiabiav (hu ua uranium iav) txog xyoo 1950.
