Isiqingatha-ubomi uranium: iimpawu eziphambili kunye nesicelo

Ukufunda le ngxaki yokusetyenziswa imisebe, isazinzulu ubhekisela kule mpawu zibalulekileyo njengoko isiqingatha-ubomi. Njengoko usazi, umthetho ukubola radioactive ithi yesibini yonke ehlabathini kukho sokonakalisa athom, kwaye uphawu ubuninzi bezi nkqubo inxulumene ngqo kunye nenani athom. Ukuba ixesha elithile ziya zisonakala zide isiqingatha yonke nani elifumanekayo-athom, i-½ ukubola ye-athom esisashiyekileyo siya kufuna isixa elinye ixesha. Oku eli xesha kuthiwa isiqingatha-ubomi. izinto ezahlukeneyo ngayo yahlukile - ukusuka kumawaka-millisecond ukuba ezigidi zeminyaka, njengoko, umzekelo, kwimeko xa kufikwa ixesha uranium pro-ebomini.

Uranium yi esisinda zonke izinto ezikhoyo kwi imeko yendalo ehlabathini, oko ngokubanzi into kakhulu elihle ukufunda kwinkqubo yemisebe. Le element lwafumaneka ka1789 yi-nzulu waseJamani M. Klaproth, ngubani igama wokuwonga elaa langa lwafunyanwa kutshanje Uranus. Into yokuba uranium na radioactive, oko ngempazamo afumaneka ekupheleni kwenkulungwane XIX yi yasekhemesti A. French Becquerel.

Isiqingatha-ubomi of uranium ibalwa ngokusebenzisa indlela efanayo njengoko maxesha ahambelanayo kwezinye izinto radioactive:

T_ {1/2} = au ln 2 = frac {ln 2} {Lambda},

apho «au» - lokudla avareji i-atom; «Lambda» - engundoqo ukubola njalo. Ekubeni ln 2 lingana malunga 0.7, nakwisiqingatha ubomi% 30 kuphela avareji elifutshane iyonke ebomini atom.

Nangona ukuza kuthi ga ngoku, 14 izazinzulu ezaziwayo izinto ezineeathom ezilinganayo uranium yazo ngokwendalo kwenzeka kuphela mathathu: neyuranium-234, neyuranium-235 neyuranium-238. Isiqingatha-ubomi of uranium yahlukile: asingomzekelo U-234 nguye "kuphela" iminyaka 270 lamawaka, kunye nesiqingatha-ubomi neyuranium-238 kune 4.5 billion. uranium-235 nesiqingatha ebomini kwi "imin yegolide" - eminyakeni million 710.

Kufuneka kuqatshelwe ukuba uranium radioactivity in vivo liphezulu ngokwaneleyo, umzekelo, ipleyiti yokuthathwa ukuba ubakhanyisele kwisithuba iiyure kuphela. Ngelo xesha linye kubalulekile ukukhumbula ukuba yonke Isotope uranium U-235 ilungele kuphela ukuba nokuveliswa ukuwavala ukuba ibhombu yenyukliya. Eyona nto kukuba neyuranium-235 isiqingatha ubomi kwimeko mveliso lingaphantsi kakhulu kunokuba 'abazalwana' bakhe, yaye ngenxa yoko imveliso ye neutron ngokungeyomfuneko sakugcina.

uranium-238, nakwisiqingatha ubomi ngokuphawulekayo kwiminyaka eziibhiliyoni ezi-4 Noko ke, kwaye ngoku isetyenziswa kakhulu kushishino yenyukliya. Ukuze ukuqala yokusabela nomxokelelwane ngokucandeka of nuclei enzima lwesi sakhi kufuneka isixa esikhulu wamandla neutron. 238 isetyenziswa njengokhuselo kwi ngokucandeka nokumanyana nezixhobo. Noko ke, uninzi kufunxwa neyuranium-238 isetyenziselwa Yindibanisela neplutoniyam ezisetyenziswa izixhobo zenyukliya.

Ixesha besiqingatha ubomi izazinzulu uranium sebenzisa ukubala ubudala izimbiwa ngamnye kunye imizimba yasezulwini ngokubanzi. iiwoshi uranium na indlela noko jikelele ukuba izibalo ezinje. Ngelo xesha ukuba yobudala sele ubalwe ngaphezulu okanye ngaphantsi ngokuchanekileyo, kuyimfuneko ukwazi nje kuphela isixa uranium e iintlobo ezahlukeneyo, kodwa umlinganiselo uranium belahlekisa imveliso yokugqibela, leyo baguqula ngumongo uranium.

Kukho nenye indlela ukubala namatye neeminerali, inxulunyaniswa ekuthiwa-kulogo ngokucandeka of uranium. Njengoko waziwa kakuhle, ngenxa yokuba lo ngokucandeka yezizwe uranium kwiimeko yendalo isuntswana ngamandla omkhulu inqwaba inani kukho izinto, eshiya imizila olukhethekile - tracks.

Kungenxa inani lengoma, esazi ixesha isiqingatha-ubomi uranium, yaye izazinzulu waqukumbela malunga eneminyaka umzimba engqongqo - nokuba yinto uhlobo mandulo, okanye ivazi ngokwentelekiso "abaselula". Eyona nto kukuba ubudala into kukuba kisekiyo ngqo nezibonisi ubuninzi-athom uranium, leyo ngethala core yayo.