Uranium yog ib yam tshuaj caij: keeb kwm ntawm lub foundations ntawm nuclear fission thiab cov tshuaj tiv thaiv

Cov tsab xov xwm qhia txog thaum no tshuaj caij sab li uranium, thiab nyob rau hauv dab tsi industries nta siv no substance.

Uranium - ib tug tshuaj caij nyob rau hauv lub zog thiab cov tub rog kev lag luam

Txhua lub sij hawm cov neeg sim mus nrhiav ib tug high-zog, thiab tob - tsim ib tug thiaj li hu ua perpetual tsab ntawv tsa suab tshuab. Tu siab, lub cev tsis muaj nws lub neej raws qhov tseeb thiab substantiated nyob rau hauv lub XIX xyoo pua, tab sis zaum tseem tsis poob cia siab tias yuav paub hauv tus npau suav ntawm ib co zoo ntawm ntaus ntawv uas yuav tsum tau muab ib tug loj tus naj npawb ntawm "huv" lub zog rau ib tug ntev heev lub sij hawm.

Qhov no yog tej kev tswj kom paub nrog lub foundations ntawm ib yam khoom xws li uranium. Ib tug tshuaj caij nrog tus muab lub npe yog lub hauv paus rau txoj kev loj hlob ntawm nuclear reactors, uas tam sim no muab lub zog rau tag nrho lub zos, submarines, ncov qaumteb qabteb ships thiab thiaj li nyob. Yeej muaj tseeb, lub "huv" lawv lub zog yuav tsis muaj npe, tab sis nyob rau hauv tsis ntev los no xyoo, muaj ntau yam tuam txhab uas muag tsim rau cov general muag khoom compact "nuclear roj teeb" rau lub hauv paus ntawm tritium - lawv muaj tsis muaj feem mus, thiab lawv muaj kev ruaj ntseg rau kev kho mob.

Txawm li cas los, nyob rau hauv no tsab xov xwm no peb yuav soj nyob rau hauv kom meej lub keeb kwm ntawm lub foundations ntawm ib tug tshuaj caij hu ua uranium fission cov tshuaj tiv thaiv thiab nws cov tsuab.

txhais

Uranium - tshuaj caij uas muaj ib tug atomic tooj 92 nyob rau hauv lub periodic rooj. Nuclear lub hwj chim yog nws cov luj yog 238,029. Nws qhia lub cim U. Nyob rau hauv tej yam tshwm sim, yog ib tug ntom, hnyav hlau nyiaj. Yog hais tias peb tham txog nws cov radioactivity, lub uranium nws tus kheej - caij nrog tsis muaj zog radioactivity. Tsis tas li ntawd, nws tsis muaj nyob rau hauv nws cov muaj pes tsawg leeg kiag li ruaj khov isotopes. Thiab lub feem ntau ruaj khov ntawm cov uas twb muaj lawm isotope uranium-338 yog xam tau tias yog.

Nyob rau hauv kev txiav txim ntawm li cas yuav muab lub caij, peb xam tawm, thiab tam sim no saib lub keeb kwm ntawm nws foundations.

zaj dabneeg

Xws li ib tug yeeb tshuaj, xws li tej yam ntuj tso uranium oxide, lub npe hu mus rau cov neeg txij ancient sij hawm, thiab siv nws ancient masters rau zus tau tej cov glazes, uas npog ntau yam tais diav ntim chaws cov hlab ntsha rau dej kuj thiab lwm yam khoom, raws li zoo raws li lawv kho kom zoo nkauj.

Ib qho tseem ceeb hnub nyob rau hauv lub keeb kwm ntawm lub foundations ntawm no tshuaj caij los ua 1789. Nws yog ces ib tug chemist thiab ib tug German-yug Martin Klaproth yog tau txais thawj metalloobrazny uranium. Thiab nws lub npe yog ib tug tshiab lub caij nyob rau hauv Honor ntawm cov lus qhib yim xyoo dhau los rau hauv lub ntiaj.

Yuav luag 50 xyoo tau thaum uranium mas suav hais tias ib tug dawb huv hlau, li cas los xij, nyob rau hauv 1840 lub Fabkis chemist Eugene-Peligot Melkor muaj peev xwm los ua pov thawj hais tias cov ntaub ntawv tau los ntawm Klaproth, txawm hais tias tsis tsim lwm yam tshwm sim, tsis yog hlau, thiab uranium oxide. Ib me ntsis tom qab, tag nrho cov tib yog muaj tseeb tiag Peligot uranium - ib tug heev hnyav hlau grey. Nws yog ces rau thawj lub sij hawm thiab lub atomic luj ntawm lub substance tau txiav txim raws li uranium. Tshuaj caij tau muab tso rau Dmitri Mendeleev nyob rau hauv nws nto moo periodic system ntawm cov ntsiab nyob rau hauv 1874, nrog Mendeleev ob npaug atomic luj ntawm lub substance ob zaug. Nws tsuas yog tom qab 12 xyoo twb empirically qhov tseeb hais tias zoo chemist yog tsis yuam kev nyob rau hauv lawv cov lus teb.

radioactivity

Tab sis qhov tiag txaus siab nyob rau hauv no ntau yog ib feem ntawm lub scientific zej zog pib nyob rau hauv 1896, thaum Becquerel nrhiav tau hais tias uranium emits rays, uas npe hu ua tom qab lub explorer - Becquerel rays. Tom qab ntawd, yog ib lub npe nrov tshaj zaum nyob rau hauv cov cheeb tsam no - Mariya Kyuri, hu ua lub phenomenon ntawm radioactivity.

Cov tom ntej no tseem ceeb hnub nyob rau hauv txoj kev tshawb no ntawm uranium yog xav tau nyob rau hauv 1899: nws yog ces hais tias Rutherford nrhiav tau hais tias uranium tawg yog tsis niaj hnub thiab yog muab faib ua ob hom - alpha thiab beta rays. Ib xyoo tom qab, Pol Villar (Viyyar) qhib thiab lub thib peb, lub xeem peb paub yog tias hnub hom ntawm hluav taws xob - qhov thiaj li hu ua gamma rays.

Xya xyoo tom qab, nyob rau hauv 1906, Rutherford raws li nws lub hom phiaj ntawm radioactivity ua thawj thwmsim, lub hom phiaj ntawm cov uas yog los mus txiav txim lub hnub nyoog ntawm ntau yam minerals. Cov kev tshawb fawb tau pw lub foundation, nrog rau cov tsim ntawm txoj kev tshawb xav thiab xyaum ntawm radiocarbon tsom xam.

Fission ntawm uranium

Tab sis tej zaum cov overriding qhib, los ntawm kev uas tau lug uranium tsuas thiab milling nyob rau hauv ob qho tib si pej xeem thiab cov tub rog lub hom phiaj - yog tus txheej txheem ntawm nuclear fission ntawm uranium. Nws tshwm sim nyob rau hauv 1938, lub foundations twb nqa tawm rog ntawm German physicists Otto Gana thiab Fritz Strassmann. Tom qab ntawd no ziag no twb paub tseeb hais tias nyob rau hauv scientific tej hauj lwm ntawm ob peb German physicists.

Lub mechanism sab los ntawm lawv yog raws li nram no: yog hais tias tus ntsiav irradiated uranium-235 isotope neutron, ces niag cov dawb neutron, nws pib mus rau faib. Thiab, raws li peb tam sim no paub, txoj kev no yog nrog los ntawm ib tug enormous nqi ntawm lub zog. Qhov no tshwm sim mas vim lub kinetic zog ntawm cov tawg, nucleus tawg tsam. Yog li ntawd tam sim no peb paub yuav ua li cas lub fission ntawm uranium.

Tus foundations ntawm no mechanism thiab nws tau, thiab yog tus pib taw tes rau cov kev siv ntawm uranium nyob rau hauv lub pej xeem thiab cov tub rog lub hom phiaj.

Yog hais tias peb tham txog nws cov kev siv rau cov tub rog lub hom phiaj, rau cov thawj lub sij hawm ib tug kev tshawb xav hais tias muaj peev xwm tsim cov tej yam kev mob rau xws li ib tug txheej txheem, raws li ib tug tas mus li cov tshuaj tiv thaiv ntawm uranium fission (raws li mus rau undermine lub nuclear foob pob yuav tsum tau zoo kawg li zog), muaj pov thawj los ntawm Soviet physicists Zeldovich thiab Khariton. Tab sis nyob rau hauv thiaj li yuav tsim xws li ib tug tshuaj tiv thaiv, cov uranium yuav tsum tau enriched, raws li nyob rau hauv nws li ib txwm lub xeev ntawm cov kev kawm zog nws tsis muaj.

Nrog ib tug keeb kwm ntawm no peb tau nyeem, peb muaj tam sim no rhuav, qhov uas nws ua ntawv thov.

Cov kev siv thiab hom ntawm uranium isotopes

Tom qab tus foundations ntawm xws li ib tug txheej txheem, raws li ib tug tshuaj tiv thaiv ntawm uranium fission saw, physicists pib mus nug qhov chaw uas yuav siv nws?

Tam sim no, muaj ob lub ntsiab qhov chaw nyob qhov twg cov kev siv ntawm uranium isotopes. Nws yog muaj kev thaj yeeb (los yog lub zog) kev lag luam thiab cov tub rog. Ob tus thawj thiab tus thib ob siv cov tshuaj tiv thaiv ntawm nuclear fission ntawm uranium-235 isotope, raws xwb nyob rau hauv lub tso zis ntau zog. Cias muab, nyob rau hauv ib tug nuclear reactor yog tsis tsim nyog los tsim thiab txhawb txoj kev no nrog rau cov tib peev xwm raws li yog tsim nyog rau nqa tawm cov tawg ntawm ib tug nuclear foob pob.

Yog li ntawd, twb yog lub ntsiab lag luam uas siv cov uranium fission cov tshuaj tiv thaiv.

Tab sis tau txais lub isotope uranium-235 - yog tsis tshua muaj yooj yim thiab kim hauj teeb meem, thiab tsis yog txhua lub teb chaws yuav them taus los tsim ua cov nroj tsuag. Piv txwv li, rau nees nkaum tons ntawm uranium roj, nyob rau hauv cov ntsiab lus ntawm uranium 235 isotope yuav nyob nruab nrab ntawm 3-5%, nws yuav tsum tau ntau tshaj li 153 tons ntawm enriched ntuj, "nyoos" uranium.

uranium-238 isotope yog tsuas yog siv nyob rau hauv qhov kev siv tswvyim ntawm nuclear riam phom mus rau kom nws cov peev xwm. Tsis tas li ntawd, thaum nws captures ib tug neutron ua raws li los ntawm tus txheej txheem ntawm beta lwj ntawm no isotope yuav nws thiaj li yuav hloov dua siab tshiab rau hauv plutonium-239 - ib qho roj rau feem ntau ntawm hnub no lub nuclear reactors.

Txawm tias tag nrho cov shortcomings ntawm xws reactors (nqi, complexity ntawm kev kho mob, txoj kev pheej hmoo ntawm kev huam yuaj), lawv lub lag luam them rau nws tus kheej heev sai sai, thiab lub zog lawv tsim yog incomparably ntau dua qhov classical thermal los yog pas hwj chim.

Tsis tas li ntawd, cov uranium fission cov tshuaj tiv thaiv yog tau tso cai los tsim nuclear riam phom uas huab hwm coj puas tsuaj. Nws yog yus muaj los ntawm yawm quab yuam yog tus compact thiab hais tias yog muaj peev xwm ua ntau av unsuitable rau tib neeg habitation. Txawm li cas los, nyob rau hauv niaj hnub nuclear riam phom yog siv plutonium es uranium.

depleted uranium

Muaj kuj yog xws li ib yam ntawm cov uranium yog depleted. Nws yog yus muaj los ntawm heev tsawg theem ntawm radioactivity thiab yog li ntawd tsis txaus ntshai rau tib neeg. Nws thov dua nyob rau hauv cov tub rog kheej, piv txwv li, nws yog ntxiv nyob rau hauv lub armor "Abrams" American tank muab nws ntau fort. Nyob rau hauv tas li ntawd, yuav luag tag nrho cov high-tech cov tub rog ua tau raws li ib tug ntau yam ntawm cuaj luaj nrog depleted uranium. Nyob rau hauv tas li ntawd mus rau high luj, lawv muaj tsis tau lwm heev interesting feature - tom qab kev puas tsuaj ntawm nws plhaub splinters thiab hlau hmoov zes nthawv. Thiab los ntawm txoj kev, cov thawj lub sij hawm xws li ib tug missile twb siv thaum lub sij hawm ob ntiaj teb rog. Raws li peb tau pom, uranium - lub ntsiab uas tau siv nyob rau hauv ntau yam teb ntawm tib neeg kev ua si.

xaus

Zaum kwv yees hais tias nyob ib ncig ntawm 2030 kiag li sab sab tag nrho cov yam ntawm cov loj uranium deposits, thiab ces pib cov kev loj hlob ntawm nws cov nyuaj-khaubncaws sab nraud povtseg, thiab tus nqi yuav sawv. Txoj kev, qhov uranium ore yog kiag li txawm rau tib neeg - ib co yooj ua hauj lwm nyob rau hauv nws ntau lawm rau tiam. Tam sim no peb to taub lub keeb kwm ntawm lub foundations ntawm cov tshuaj hais, thiab yuav ua li cas siv nws nuclear fission cov tshuaj tiv thaiv.

Los ntawm txoj kev, ib qho kev nthuav qhov tseeb yog paub rau - uranium tebchaw tau ntev tau siv raws li xim tsev rau iav thiab iav (thiaj li hu ua uranium iav) kom txog rau thaum lub sijhawm xyoo 1950.