ʻO ka pōʻino radiation o ka pauka graphite he hopena koʻikoʻi i ka hana loea a me ka hoʻokele waiwai o ka reactor, ʻoiai ka reactor pebble bed kiʻekiʻe wela gas-cooled. ʻO ke ʻano o ka neutron moderation ʻo ia ka elastic scattering o neutrons a me nā ʻātoma o ka mea moderating, a ʻo ka ikehu i lawe ʻia e lākou e hoʻoili ʻia i nā ʻātoma o ka mea moderating. He moho hoʻohiki nō hoʻi ka pauka graphite no nā mea plasma-oriented no nā reactors fusion nuklea. Hoʻolauna nā mea hoʻoponopono aʻe mai Fu Ruite i ka hoʻohana ʻana o ka pauka graphite i nā hoʻāʻo nuklea:
Me ka hoʻonui ʻia ʻana o ka neutron fluence, emi mua ka pauka graphite, a ma hope o ka hiki ʻana i kahi waiwai liʻiliʻi, emi ka emi ʻana, hoʻi i ka nui mua, a laila hoʻonui koke. I mea e hoʻohana pono ai i nā neutrons i hoʻokuʻu ʻia e ka fission, pono e hoʻolohi ʻia. Loaʻa nā waiwai wela o ka pauka graphite ma o ka hoʻāʻo irradiation, a pono e like nā kūlana hoʻāʻo irradiation me nā kūlana hana maoli o ka reactor. ʻO kekahi ana e hoʻomaikaʻi ai i ka hoʻohana ʻana i nā neutrons, ʻo ia ka hoʻohana ʻana i nā mea reflective e hōʻike i nā neutrons e puka ana mai ka nuclear fission reaction zone-core back. ʻO ke ʻano o ka neutron reflection ʻo ia hoʻi ka elastic scattering o nā neutrons a me nā ʻātoma o nā mea reflective. I mea e kāohi ai i ka pohō i hana ʻia e nā haumia i ka pae i ʻae ʻia, pono ka pauka graphite i hoʻohana ʻia i loko o ka reactor i maʻemaʻe nuklea.
ʻO ka pauka graphite nukelea kahi lālā o nā mea pauka graphite i hoʻomohala ʻia ma ke ʻano he pane i nā pono o ke kūkulu ʻana i nā reactors fission nukelea i ka hoʻomaka ʻana o nā makahiki 1940. Hoʻohana ʻia ia ma ke ʻano he moderator, reflection a me nā mea kūkulu i nā reactors hana, nā reactors i hoʻomaʻalili ʻia e ke kinoea a me nā reactors i hoʻomaʻalili ʻia e ke kinoea. ʻO ka likelika o ka neutron e pane ana me ka nucleus ua kapa ʻia ʻo ka ʻāpana kea, a ʻo ka neutron thermal (awelika ikehu o 0.025eV) fission cross section o U-235 he ʻelua mau papa kiʻekiʻe ma mua o ka fission neutron fission (awelika ikehu o 2eV) fission cross section. Hoʻonui ka modulus elastic, ka ikaika a me ke coefficient hoʻonui linear o ka pauka graphite me ka hoʻonui ʻana o ka neutron fluence, hiki i kahi waiwai nui, a laila e emi koke ana. I ka hoʻomaka ʻana o nā makahiki 1940, ʻo ka pauka graphite wale nō i loaʻa ma ke kumukūʻai kūpono kokoke i kēia maʻemaʻe, ʻo ia ke kumu i hoʻohana ai kēlā me kēia reactor a me nā reactors hana ma hope i ka pauka graphite ma ke ʻano he mea moderating, e hoʻolauna ana i ka wā nukelea.
ʻO ke kī i ka hana ʻana i ka pauka graphite isotropic ʻo ia ka hoʻohana ʻana i nā ʻāpana coke me ka isotropy maikaʻi: coke isotropic a i ʻole coke lua macro-isotropic i hana ʻia mai ka coke anisotropic, a me ka ʻenehana coke lua e hoʻohana nui ʻia i kēia manawa. Pili ka nui o ka pōʻino radiation i nā mea maka o ka pauka graphite, ke kaʻina hana, ka wikiwiki o ka neutron fluence a me ka fluence rate, ka mahana irradiation a me nā mea ʻē aʻe. Pono ka boron e like me ka pauka graphite nuklea ma kahi o 10 ~ 6.
Ka manawa hoʻouna: Mei-18-2022