Te Ariā Ā-tinana o te Pūngao Karihi
Ko te mana karihi tētahi o ngā pūtake pūngao tino kaha, tino tautohenga hoki i roto i te ao hou. I tētahi taha, ka taea e ia te whakaputa i te nui o te hiko me te iti rawa o ngā tukunga waro. I tētahi atu taha, ka ara ake ngā āwangawanga mō te haumaru o ngā tauhohenga, te para irahiko, me te mōrearea o te horapa o ngā patu i te mana karihi. Hei mārama he aha te kaha o te pūngao karihi me pēhea te whakamahi, me arotake e tātou ngā ariā ā-tinana e pā ana: te hanganga o te karihi ngota, ngā kaha karihi, te pūngao here, te irahiko, me ngā tukanga o te wehenga me te hanumi e huri ai te papatipu hei pūngao.
Hanganga me te Pūtake o te Atomika
He karihi iti, matotoru ngā ngota, e karapotia ana e te kapua irahiko. Kei roto i te karihi ngā porotona utu pai me ngā neutrone koretake. Tata ki te katoa o te papatipu o te ngota e kohikohia ana i roto i te karihi, ka waiho hei puna pūngao nui. He tata ki te 10.000 ngā wā iti iho te karihi i te ngota katoa, engari ko tōna papatipu he nui ake i te 99,9% o te papatipu katoa o te ngota.
He mea whakamīharo, ko ngā porotana, he rite tonu te utu pai, me pana tetahi ki tetahi nā te kaha hikohiko. Heoi, ka noho pumau tonu te karihi nā te kaha karihi kaha, he kaha taketake e mahi ana i ngā tawhiti poto rawa (i runga i te ota o te femtometer, 10⁻¹⁵ m) engari he kaha ake i te kaha hikohiko i aua tawhiti. Ko tēnei kaha karihi kaha te mea e "piri" ana i ngā porotana me ngā neutron ki roto i te karihi.
Pūngao Here me te Koha Papatipu
E pā ana te pumau karihi ki te ariā o te pūngao here, arā, te pūngao e hiahiatia ana hei wehewehe i te karihi ki roto i ōna pūrotana me ōna niutorona. I te taha tinana, ka puta te pūngao here nā te mea ina honoa ngā niutorona (ngā pūrotana me ngā niutorona) hei hanga i te karihi, he iti ake te papatipu katoa o te karihi hua i te tapeke o ngā papatipu o ia niutorona. Ka kiia tēnei rerekētanga o te papatipu ko te hapa papatipu.
E pā tika ana te hapa papatipu ki te pūngao mā te whārite rongonui a Einstein:
E = mc²
Nā te tere o te mārama (c), ahakoa he iti noa te hapa o te papatipu ka taea te whakaputa i te nui o te pūngao. Koinei te take matua e nui ake ai te pūngao e puta mai i ngā tauhohenga karihi i ngā tauhohenga matū (pērā i te mura). I roto i ngā tauhohenga matū, ko ngā hononga irahiko i waenga i ngā ngota te mea nui e rerekē ana; i roto i ngā tauhohenga karihi, ko te hanganga o te karihi tonu te mea e rerekē ana.
Te Hikohiko Irahiko: Te Pirau o te Karihi
Kāore ngā karihi ngota katoa e pumau. Ka pāngia ngā karihi kore pumau e te pirau irahiko kia eke ki tētahi āhua pumau ake. Ka puta te āhua o tēnei pirau penei:
1. Te irahiko ārepa (α): te tukunga o te karihi hēriuma (2 ngā porotona me 2 ngā irahiko niutoronika).
2. Te irahiko Beta (β): te huringa o ngā neutron ki ngā porotona (ki te huri rānei) me te tukunga o ngā irahiko, ngā positron me ngā neutrino rānei.
3. Te irahiko gamma (γ): te tukunga o ngā photon pūngao-tiketike nā te nekehanga o te karihi ki tētahi taumata pūngao iti iho.
He mea nui te irahiko i roto i te horopaki o te mana karihi nā te mea he irahiko ngā hua o te wehenga me te wahie karihi. He mea nui te mārama ki ngā momo irahiko me te āhua o te tiaki i a rātou ki te haumaru o te tauhohenga me te whakahaere para.
Ko tētahi atu ariā nui ko te haurua-ora, te wā e hiahiatia ana kia heke te maha o ngā karihi irahiko mā te haurua. Ka rerekē ngā haurua-ora mai i ngā haurua o te hēkona ki ngā miriona tau, ā, he pānga tika tēnei ki ngā rautaki rokiroki para irahiko.
Te Wehenga Karihi: Pūtake Pūngao i roto i ngā Whare Mana Karihi
Ko te nuinga o ngā tipu hiko karihi (NPP) e whakahaerehia ana i tēnei wā i runga i te wehenga karihi, arā, te wehenga o ngā karihi taumaha ki ngā karihi māmā ake. Ko te tauira tino kitea ko te wehenga o te uranium-235 (U-235). Ina "hopukina" he niutron e te karihi U-235, ka kore e pumau te karihi (U-236) kātahi ka wehea kia rua ngā wāhanga wehenga, ka tukuna he maha atu o ngā niutron me te pūngao i roto i te ahua o te pūngao nekeneke o ngā wāhanga, te irahiko gamma, me te wera.
Ko te pūngao e tukuna ana mō ia wehenga kei te 200 MeV (mega-electron volts). Ki te whakaritea ki te pūngao o te tauhohenga matū, he torutoru noa iho ngā eV mō ia ngota, he tino nui te rerekētanga.
Ngā Tauhohenga Mekameka me ngā Tauwehe Whakarea
Ko te kī ki te whakamahi i te wehenga i roto i te tauhohenga ko te tauhohenga mekameka. Ka taea e ngā neutron i tukuna mai i tētahi wehenga te whakaoho i ngā wehenga e whai ake nei. Kia pumau ai te haere o te tauhohenga mekameka, me "taurite" te maha o ngā neutron e hua ai ngā wehenga e whai ake nei. Ka whakaatuhia tēnei ariā e te tauwehe whakarea whai hua (kₑff):
– kₑff < 1: ka heke te tauhohenga (iti te aro) - kₑff = 1: he pumau te tauhohenga (iti te aro) - kₑff > 1: ka piki te tauhohenga (tino aro)
Ka whakahaerehia ngā tauhohenga hiko kia tata rawa atu ki ngā āhuatanga tino kino (kₑff ≈ 1) hei whakaputa wera i runga i te āhua pumau me te whakahaere.
Kaiwhakahaere, Rakau Whakahaere, me te Kaiwhakamātao
Ko ngā neutrone wehenga he nui te kaha (ngā neutrone tere). Heoi, he nui ake te tūponotanga o te wehenga U-235 mō ngā neutrone puhoi (ngā neutrone wera). Nō reira, he maha ngā tauhohenga e whakamahi ana i ngā kaiwhakaōrite (hei tauira, te wai māmā, te wai taumaha, te karāhe rānei) hei whakaroa i ngā neutrone mā roto i ngā tukinga.
Hei whakahaere i te maha o ngā niutron, ka whakamahia e ngā tauhohenga ngā tokotoko whakahaere i hangaia mai i ngā rauemi mimiti niutron pērā i te boron, te cadmium, te hafnium rānei. Mā te whakauru, te tango rānei i ngā tokotoko whakahaere, ka taea e ngā kaiwhakahaere te whakanui ake, te whakaiti rānei i te tere o ngā tauhohenga wehenga.
Kātahi ka whakawhitia te wera e puta mai ana e te wai whakamatao—he maha ngā wā ko te wai—ki te whakawhiti wera hei whakaputa i te mamaoa e huri ai te tāpine me te whakaputa hiko. I roto i te ariā, he rite te wāhanga tāpine-whakaputa hiko ki ētahi atu tipu hiko wera; ko te rerekētanga kei te pūtake wera.
Te Whakakotahitanga Karihi: Te Pūngao Whetu me te Tumanako ā-Mārama
Haunga te wehenga, kei reira tētahi atu tukanga karihi e whakaputa ana i te pūngao nui: te hanumitanga karihi, te hanumitanga o ngā karihi māmā ki ngā karihi taumaha. I roto i te Rā, ka hanumi te hauwai hei hanga i te herium, ka tukuna te pūngao e tiaho ai ngā whetū.
Ko te tauhohenga hanumi e tino rangahauhia ana mō te pūngao i runga i te Ao ko te deuterium–tritium (D–T):
D + T → He-4 + niutron + pūngao
He nui te kaha o te whakakotahitanga nā te mea he nui te wahie (te deuterium mai i te wai moana) ā, he iti ake pea te para irahiko roa e puta mai ana i te wehenga. Heoi, he nui ngā wero: ka panaia e ngā karihi utu pai tetahi ki tetahi, me te hiahia ki ngā pāmahana tino teitei (tekau ki te rau miriona nekehanga) kia nui ai te kaha o ngā matūriki ki te wikitoria i te arai Coulomb. Nā te mea kāore e taea e tētahi ipu rauemi te pupuri i tētahi plasma wera pēnei, ka whakamahia te here aukume (tokamak, stellarator) te here inertial rānei (ngā laser tino kaha).
Ahakoa te nui o ngā ahunga whakamua kua tutuki, kei te aro tonu te hanumitanga mō te whakaputa hiko arumoni ki ngā wero hangarau pēnei i te pumau o te plasma, ngā rauemi ātete-niutron, me te whai huatanga whānui o te pūnaha.
Mai i te Pūngao Karihi ki te Hiko: Ngā Āhuatanga o te Thermodynamics
I te taha tinana, he miihini wera te tipu hiko karihi. Ko te kaha e puta mai ana i te wehenga (i muri mai rānei, te hanumi) ka huri hei kaha wera. Ka whakamahia tēnei wera hei whakaputa i te mamaoa e huri ai te tāwhana. Nā ngā ture o te thermodynamics, ka herea te whai huatanga o te hurihanga wera ki te hiko e te rerekētanga pāmahana i waenga i te pūtake wera me te taiao. Nō reira, ko ngā hoahoa tauhohenga e kaha ana ki te mahi i ngā pāmahana teitei ake he maha ngā wā ka pai ake te whai huatanga, engari me whai rauemi matatau ake me ngā pūnaha haumaru.
Te Haumaru me te Irahiko: He Tirohanga ā-Tino
Ko te haumaru karihi e whakawhirinaki ana ki te māramatanga ki te irahiko me te whanonga o te tauhohenga. Ka taea e te irahiko whakakoi te kino i te kiko koiora mena he nui te horopeta. Nō reira, ka whakamahia e ngā tipu hiko karihi te mātāpono parepare-hohonu, arā, ko ngā paparanga tiaki: te whakakikorua wahie, te ipu tauhohenga, te pūnaha whakamatao, me te hanganga pupuri. Mai i te tirohanga ā-tinana, ko te whāinga matua ko te pupuri i te tauhohenga kia kaua e nekehia, kia tika te horapa o te wera, kia wehea hoki ngā hua irahiko.
Te Katinga
Ko ngā ariā ā-tinana o te mana karihi e aro ana ki te kaha here karihi, te hapa papatipu, me te hurihanga o te papatipu ki te kaha mā te E = mc². Ka whakamahia e te wehenga o ngā karihi taumaha me te tauhohenga mekameka whakahaeretia me ngā kaiwhakahaere me ngā tokotoko whakahaere, ko te hanumi ka whai i ngā tukanga whetu mā te whakakotahi i ngā karihi māmā i raro i ngā āhuatanga tino kino. E whakaatu ana ngā tukanga e rua i te kaha nui e rongoatia ana i roto i ngā karihi ngota. He mea nui te mārama ki ēnei ahupūngao taketake kia kaua e ārahihia ngā kōrero mō te kaha karihi e te wehi, e te tumanako rānei, engari e te mōhiotanga pūtaiao hoki mō te mahi a te hangarau, ōna painga, me ngā mōrearea e tika ana kia whakahaerea tika.
