{"id":4110,"date":"2014-04-04T03:34:20","date_gmt":"2014-04-04T01:34:20","guid":{"rendered":"http:\/\/www.ilkkimbuldu.com\/?p=4110"},"modified":"2018-02-28T23:05:21","modified_gmt":"2018-02-28T21:05:21","slug":"uranyumu-kim-buldu","status":"publish","type":"post","link":"https:\/\/www.ilkkimbuldu.com\/?p=4110","title":{"rendered":"Uranyumu kim buldu"},"content":{"rendered":"

Uranyum periyodik tablonun III B grubundaki aktinitler serisinde\u00a0yer alan radyoaktif kimy\u00e2sal elementtir. Yo\u011fun, sert ve g\u00fcm\u00fc\u015f beyaz\u0131 renginde bir metal olan uranyum\u00a0tabi\u00ee elementler aras\u0131nda atom a\u011f\u0131rl\u0131\u011f\u0131 en y\u00fcksek olan\u0131d\u0131r. Kimy\u00e2da \u201cU\u201d sembol\u00fcyle g\u00f6sterilir. 1789\u2019da Martin Heinrich Klaproth<\/strong> taraf\u0131ndan ke\u015ffedilen uranyum E.M. P\u00e9ligot taraf\u0131ndan 1841 y\u0131l\u0131nda uranyum-4-oksitten\u00a0(UO2) izole edildi. 1896\u2019da Henri Bucquerel uranyumun radyoaktif bir element oldu\u011funu ke\u015ffetti.<\/p>\n

1934\u2019te Fermi ve \u00e7al\u0131\u015fma arkada\u015flar\u0131 uranyumun \u00df-\u0131\u015f\u0131mas\u0131 yapt\u0131\u011f\u0131n\u0131 buldular. 1938\u2019de Hahn ve\u00a0Strassmann uranyumu n\u00f6tronla bombard\u0131man ederek daha hafif elementler elde ettiler.\u00a01939\u2019da Fermi, uranyumun \u00e7ekirdek reaksiyonlar\u0131n\u0131n zincir reaksiyonlar\u0131 oldu\u011funu s\u00f6yledi. 1939\u00a0y\u0131l\u0131nda ara\u015ft\u0131rmac\u0131lar U235\u2019in fisyon reaksiyonu verebilece\u011fini g\u00f6sterdiler. 1942\u2019de n\u00fckleer zincir\u00a0reaksiyon yap\u0131ld\u0131. Uranyumdan yap\u0131lm\u0131\u015f atom bombas\u0131 1945\u2019te kullan\u0131ld\u0131.<\/p>\n

Di\u011fer elementlere g\u00f6re az bulunan uranyumun d\u00fcny\u00e2daki mevcut miktar\u0131n\u0131n 1014 ton\u00a0oldu\u011fu tahmin ediliyor. Yakla\u015f\u0131k ve ortalama olarak her bir gram kayada 4×10-6g uranyum vard\u0131r.\u00a0Deniz suyu milyarda \u00fc\u00e7 nispetinde uranyum ihtiv\u00e2 eder.<\/p>\n

Atom numaras\u0131 92, atom a\u011f\u0131rl\u0131\u011f\u0131 238,03\u2019t\u00fcr. 1132\u00b0C\u2019de erir, 3818\u00b0C\u2019de kaynar. Yo\u011funlu\u011fu 19,06\u00a0g\/cm3t\u00fcr. Uranyum 0,68\u00b0K\u2019de s\u00fcper iletken olup olduk\u00e7a aktif bir metaldir. Oda s\u0131cakl\u0131\u011f\u0131nda hava\u00a0temas\u0131 ile hemen sar\u0131, bir m\u00fcddet sonra tam\u00e2men siyah renk al\u0131r. Azot, karbon monoksit, karbon
\ndioksit ve di\u011fer gazlarla reaksiyon verir. Bu sebepten uranyum laboratuvarda asal (soy) gazlar\u0131n\u00a0safla\u015ft\u0131r\u0131lmas\u0131nda kullan\u0131l\u0131r.<\/p>\n

Atom enerjisi \u00fcretiminde kullan\u0131lmadan \u00f6nce uranyumun \u00e7ok az bir pratik uygulamas\u0131\u00a0vard\u0131r. Seramiklerde, foto\u011fraf\u00e7\u0131l\u0131kta, kimyev\u00ee reaksiyonlarda kataliz\u00f6r olarak ve daha birka\u00e7 i\u015flemde\u00a0kullan\u0131lmas\u0131na ra\u011fmen, b\u00fct\u00fcn bu uygulamalar uranyumun ayr\u0131 bir element olarak istihs\u00e2lini\u00a0gerektirmiyor ve uranyum radyum end\u00fcstrisinin bir yan \u00fcr\u00fcn\u00fc olarak \u00fcretiliyordu. N\u00fckleer enerjinin\u00a0kullan\u0131m\u0131nda uranyum uygulamas\u0131, durumu tam\u00e2men de\u011fi\u015ftirdi: Uranyum as\u0131l m\u00e2mul, radyum ise\u00a0olduk\u00e7a daha az \u00f6nemli bir yan \u00fcr\u00fcn durumuna ge\u00e7ti.<\/p>\n

B\u00fct\u00fcn uranyum izotoplar\u0131 n\u00fckleer yak\u0131t olarak kullan\u0131labilir. Tam bir par\u00e7alanma sa\u011flan\u0131rsa bir paund\u00a0(yakla\u015f\u0131k 454 gr) yak\u0131t 10.000 kilowatt-saat enerji verir. Bu b\u00fcy\u00fck miktardaki enerjinin kontrollu \u015fartlar\u00a0alt\u0131nda kullan\u0131lmas\u0131 \u00e7al\u0131\u015fmalar\u0131 s\u00fcrd\u00fcr\u00fclmekte ve bir sonuca ula\u015fma konusunda \u00fcmitli
\nbulunulmaktad\u0131r.<\/p>\n

Normal izotopik kompozisyonu ile tabi\u00ee uranyum, n\u00fckleer reakt\u00f6rlerde kullan\u0131labilir. Buralarda\u00a0par\u00e7alanarak enerjiye d\u00f6n\u00fc\u015ft\u00fcr\u00fcl\u00fcr. Bu i\u015flemde uranyumun bir k\u0131sm\u0131 plutonyuma d\u00f6n\u00fc\u015f\u00fcr. Bu da\u00a0zincirleme patlama reaksiyonlar\u0131nda kullan\u0131labilir. Tabi\u00ee uranyumun kendisi patlay\u0131c\u0131 olarak
\nkullan\u0131lamaz. Fakat U-235 izotopu ondan ayr\u0131larak, plutonyum gibi, patlamal\u0131 reaksiyonlar meydana\u00a0getirmek \u00fczere kullan\u0131labilir.<\/p>\n","protected":false},"excerpt":{"rendered":"

Uranyum periyodik tablonun III B grubundaki aktinitler serisinde\u00a0yer alan radyoaktif kimy\u00e2sal elementtir. Yo\u011fun, sert ve g\u00fcm\u00fc\u015f beyaz\u0131 renginde bir metal olan uranyum\u00a0tabi\u00ee elementler aras\u0131nda atom a\u011f\u0131rl\u0131\u011f\u0131 en y\u00fcksek olan\u0131d\u0131r. Kimy\u00e2da…<\/p>\n","protected":false},"author":1,"featured_media":10584,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[92],"tags":[2242],"class_list":["post-4110","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bilim","tag-uranyum"],"_links":{"self":[{"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=\/wp\/v2\/posts\/4110"}],"collection":[{"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4110"}],"version-history":[{"count":7,"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=\/wp\/v2\/posts\/4110\/revisions"}],"predecessor-version":[{"id":10586,"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=\/wp\/v2\/posts\/4110\/revisions\/10586"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=\/wp\/v2\/media\/10584"}],"wp:attachment":[{"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4110"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4110"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ilkkimbuldu.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4110"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}