A rabin-rai na uranium: babban halaye da kuma aikace-aikace

Nazarin sabon abu na radioactivity, wani masanin kimiyya yana nufin wannan mafi muhimmanci halaye a matsayin rabin-rai. Kamar yadda ka sani, dokar rediyoaktif lalata furta cewa kowane biyu a duniya akwai wani Lalacewar kwayoyin halitta, da kuma gwada yawa halayyar wadannan matakai ne kai tsaye da nasaba da yawan kwayoyin halitta. Idan wani lokaci zai lalace rabin dukan na samuwa yawan kwayoyin halitta, da lalata ½ na sauran sunadaran zasu buƙaci wannan adadin lokaci. An wannan lokaci lokaci ne da ake kira rabin-rai. Daban-daban abubuwa shi ne daban-daban - daga thousandths na ƴan daƙiƙa zuwa biliyoyin shekaru, kamar yadda, misali, a cikin hali lõkacin da ta je pro-rai lokaci na uranium.

Uranium ne heaviest dukkan data kasance abubuwa a cikin halitta jihar a duniya, shi ne kullum mafi kyau abu a nazarin radioactivity tsari. Wannan kashi da aka gano a cikin 1789 da Jamus masanin kimiyya M. Klaproth, wanda mai suna shi a cikin girmamawa ga Ganowar kwanan nan duniyar tamu Uranus. Gaskiyar cewa uranium ne rediyoaktif, shi aka bazata samu a karshen cikin XIX karni da Faransa sunadarai A. Becquerel.

A rabin-rai na uranium lasafta ta yin amfani da wannan dabara kamar yadda daidai lokaci a cikin wasu rediyoaktif abubuwa:

T_ {1/2} = au Ln 2 = frac {Ln 2} {lambda},

inda «au» - da talakawan rayuwa zarra, «lambda» - da babban lalata m. Tun LN 2 daidaita game da 0.7, da rabin rayuwa na ne kawai 30% a kan talakawan guntu fiye da jimlar rayuwa zarra.

Duk da cewa zuwa ranar, 14 masana kimiyya da aka sani isotopes na uranium a cikin yanayi faruwa ne kawai uku: uranium-234, uranium-235 da kuma uranium-238. A rabin-rai na uranium ne daban-daban: al'amarin for U-234 shi ne "kawai" 270 shekara dubu, da rabi-rai na uranium-238 ya wuce 4.5 biliyan. uranium-235 rabin rayuwa ne a cikin "zinariya nufin" - 710 shekaru miliyan.

Ya kamata a lura cewa uranium radioactivity a vivo ne babban isa zuwa, alal misali, wani daukar hoto farantin da haske a cikin kawai hours. A daidai wannan lokaci shi ne ya kamata a lura da cewa a duk na uranium isotope U-235 ne kawai dace domin yi na fillings for nukiliya bam. The abu ne cewa, uranium-235 rabin rayuwa a cikin wani yanayi na masana'antu ne kasa m fiye da "yan'uwa", sabili da haka da fitarwa na dole ba neutrons ne kadan.

uranium-238, da rabin rayuwa ne muhimmanci fiye da biliyan 4 shekaru, duk da haka, da ya ke yanzu yadu a yi amfani da makaman nukiliya masana'antu. Saboda haka kamar yadda ya fara da sarkar dauki na fission nauyi nuclei wannan kashi bukatar wani gagarumin adadin neutron makamashi. 238 da ake amfani da matsayin kariya a fission da Fusion na'urorin. Duk da haka, mafi yawan sinadarin uranium-238 da ake amfani da kira na plutonium amfani da makaman nukiliya.

A tsawon lokaci na rabin-rai na uranium masana kimiyya amfani da yin lissafi da shekaru daga cikin mutum ma'adanai da kuma na sama jikin a general. Uranium agogo ne fairly duniya inji ga irin lissafin. A lokaci guda cewa shekaru An lasafta fiye ko žasa daidai, shi wajibi ne su san ba kawai adadin uranium a daban-daban breeds, amma kuma da rabo daga uranium da kuma kai matsayin karshe samfurin, wanda ya tuba da uranium tsakiya.

Akwai kuma wata hanya zuwa lissafi da kankara da kuma ma'adanai, shi ake dangantawa da ake kira maras wata-wata fission na uranium. Kamar yadda aka sanannu, a sakamakon kwatsam fission na uranium a yanayi na mai barbashi tare da babban karfi bombarded lamba ne da abubuwa, da barin burbushi na musamman - waƙoƙi.

Yana da ga cikin yawan waƙoƙi, da sanin da rabin rayuwa tsawon uranium, da kuma masana kimiyya kammala game da shekaru a m jiki - ko da shi ne daɗaɗɗe irin, ko da wani gwada "matasa" gilashin fure. The abu ne cewa, cikin shekaru da wani abu ne kai tsaye na gwargwado ga gwada yawa Manuniya na uranium kwayoyin halitta, wanda bombarded da ginshikin.