Pamberi pehutatu hutatu, ndiko kuti, nezve kuwanikwa kweiyo yakagadzirwa radioactivity

Nguva nenguva munhoroondo yefizikisi kune makore "anoshamisa" apo kushanda pamwe kwevatsvakurudzi vakawanda kunotungamira kune zvakatevedzana zvakawanikwa. Ndizvo zvakanga zvakaita 1820, gore remagetsi, 1905, gore renenji ramapepa mana aEinstein, 1913, gore rine chokuita nenzvero yechimiro cheatomu, uye pakupedzisira, 1932, apo nhevedzano yezviwanwa zvounyanzvi nefambiro mberi mukati. simba renyukireya rakagadzirwa.

vachangobva kuchata

Irina, mwanasikana mukuru waMarie Skłodowska-Curie naPierre Curie, akaberekerwa muParis muna 1897 (1). Kusvikira pazera remakore gumi nemaviri, akakurira kumba, mu "chikoro" chiduku chakagadzirwa nemasayendisiti akakurumbira kune vana vake, maiva nevadzidzi vanenge gumi. Vadzidzisi vacho vaiva: Marie Sklodowska-Curie (fizikisi), Paul Langevin (masvomhu), Jean Perrin (chemistry), uye vanhu vainyanya kudzidziswa navanaamai vevadzidzi. Zvidzidzo zvaiwanzoitikira mudzimba dzevadzidzisi, nepo vana vaidzidza fizikisi nekemesitiri mumarabhoritari chaiwo.

Saka, dzidziso yefizikisi nekemesitiri kwaive kuwanikwa kwezivo kuburikidza nezviito zvinoshanda. Kuedza kwega kwega kwakabudirira kwakafadza vaongorori vechidiki. Uku kwaiva kuedza chaiko kwaida kunzwisiswa nokuitwa nokungwarira, uye vana vaiva murabhoritari yaMarie Curie vaifanira kuva munhevedzano yomuenzaniso. Ruzivo rwefungidziro rwaifanirawo kuwanwa. Nzira yacho, semugumo wevadzidzi vechikoro ichi, gare gare masayendisiti akanaka uye akatanhamara, yakaratidza kuva inoshanda.

2. Frederic Joliot (mufananidzo Harcourt)

Uyezve, sekuru vababa vaIrena, chiremba, vakapa nguva yakawanda kumuzukuru wababa vake aiva nherera, vachinakidzwa uye vachiwedzera dzidzo yake yesainzi. Muna 1914, Irene akapedza kudzidza kubva kuCollège Sévigé yekupayona uye akapinda muchikoro cheMasvomhu neSainzi paSorbonne. Izvi zvakapindirana nekutanga kweHondo Yenyika Yekutanga. Muna 1916 akabatana naamai vake uye pamwe chete vakaronga basa reradiological muFrench Red Cross. Hondo yapera, akagamuchira dhigirii reBachelor. Muna 1921, basa rake rokutanga resayenzi rakabudiswa. Akanga akazvipira pakutsunga kweatomu yeklorini kubva kune zvakasiyana-siyana zvicherwa. Mune mamwe mabasa ake, akashanda pamwe chete naamai vake, achibata neradioactivity. Muchinyorwa chake chechiremba, chakadzivirirwa muna 1925, akadzidza ma alpha particles akabudiswa nepolonium.

Frederic Joliot akaberekwa muna 1900 muParis (2). Kubva pazera ramakore masere akapinda chikoro muSo, aigara muchikoro chebhodhingi. Panguva iyoyo, aida mitambo kune zvidzidzo, kunyanya bhora. Akazoita majana ekuenda kuzvikoro zviviri zvepamusoro. SaIrene Curie, akafirwa nababa vake nokukurumidza. Muna 1919 akapasa bvunzo paÉcole de Physique et de Chemie Industrielle de la Ville de Paris (Chikoro cheIndustrial Physics uye Industrial Chemistry cheGuta reParis). Akapedza kudzidza muna 1923. Purofesa wake, Paul Langevin, akadzidza nezvekwaniso uye hunhu hwaFrederick. Mushure memwedzi gumi nemishanu yebasa rechiuto, pamirairo yaLangevin, akagadzwa semubatsiri werabhoritari yaMarie Skłodowska-Curie paRadium Institute nerubatsiro kubva kuRockefeller Foundation. Ikoko akasangana naIrene Curie, uye muna 15 vechiduku vacho vakaroorana.

Frederick akapedza dissertation yake yehudoctor pa electrochemistry yeradioactive element muna 1930. Nguva pfupi yapfuura, akange atoisa zvaaida patsvagiridzo yemukadzi wake, uye mushure mekudzivirira dissertation yaFrederick yezvechiremba, vakatoshanda pamwechete. Imwe yekubudirira kwavo kwekutanga kwakakosha kwaive kugadzirira kwepolonium, iyo ine simba rakasimba re alpha particles, i.e. helium nuclei.(₂⁴Iye). Vakatanga kubva pachinzvimbo chisingarambiki, nekuti aive Marie Curie akapa mwanasikana wake chikamu chikuru chepolonium. Lew Kowarsky, mubatsiri wavo gare gare, akavarondedzera sezvinotevera: Irena akanga ari “nyanzvi yakaisvonaka,” “akashanda zvakaisvonaka zvikuru uye nokungwarira,” “akanzwisisa zvikuru zvaaiita.” Murume wake aive ne "kumwe kupenya, kunowedzera kufungidzira". "Vaizadzisana zvakakwana uye vaizviziva." Kubva pakuona kwenhoroondo yesayenzi, iyo inofadza zvikuru kwavari yaiva makore maviri: 1932-34.

Vakapotsa vawana neutron

"Anenge" inokosha zvikuru. Vakadzidza nezvechokwadi ichi chinosuruvarisa nokukurumidza. Muna 1930 muBerlin, maGermany maviri - Walter Bothe i Hubert Becker -Kuongorora maitiro eatomu emwenje kana abhombwa nealpha particles. Beryllium Shield (₄⁹Be) kana yakabhombwa nealpha particles yaiburitsa yakanyanyisa kupinda uye yakakwirira-simba radhi. Sekureva kwevayedza, mwaranzi iyi inofanirwa kunge yaive yakasimba magetsi emagetsi.

Panguva ino, Irena naFrederick vakagadzirisa dambudziko racho. Kwavanobva ma alpha particles ndiwo aiva nesimba kupfuura mamwe ose. Vakashandisa kamuri yegore kuti vaone maitiro ezvigadzirwa. Pakupera kwaJanuary 1932, vakazivisa pachena kuti yakanga iri mwaranzi ye<em>gamma yakabudisa mapurotoni ane simba guru kubva muchinhu chaiva nehydrogen. Vakanga vasati vanzwisisa zvakanga zviri mumaoko avo uye kuti chii chaiitika.. Mushure mekuverenga James Chadwick (3) kuCambridge akabva atanga kushanda, achifunga kuti yakanga isiri gamma radiation zvachose, asi manyuturoni akafanotaurwa naRutherford makore akati wandei pachine nguva. Mushure mekuongorora kwakatevedzana, akagutsikana nekucherechedza neutron uye akawana kuti huwandu hwayo hwakafanana neiyo proton. Musi wa17 Kukadzi, 1932, akatumira tsamba kumagazini yeNature yakanzi "Kuvapo Kunobvira kweNeutron."

Yakanga iri nyuturoni, kunyange zvazvo Chadwick aidavira kuti neutron yaiumbwa neproton neelectron. Muna 1934 chete akanzwisisa uye kuratidza kuti neutron chinhu chekutanga. Chadwick akapiwa mubairo weNobel muFizikisiki muna 1935. Pasinei nekuziva kuti vakanga vapotsa kuwanikwa kwakakosha, Joliot-Curies akaenderera mberi nekutsvakurudza kwavo munzvimbo iyi. Vakaona kuti kuita uku kwakagadzira gamma mwaranzi mukuwedzera kumanyuturoni, saka vakanyora kuita kwenyukireya:

, apo Ef ndiyo simba re gamma-quantum. Kuedza kwakafanana kwakaitwa ne ₉¹⁹F.

Ndakapotsa kuvhura zvakare

Mwedzi mishomanana kusati kwawanikwa positron, Joliot-Curie aive nemifananidzo, pakati pezvimwe zvinhu, nzira yakakombama, sekunge yaive erekitironi, asi ichimonyorora kune yakatarisana nerekitironi. Mapikicha akatorwa mukamuri remhute riri munzvimbo ine magineti. Zvichienderana neizvi, vaviri ava vakataura nezve maerekitironi anoenda kumativi maviri, kubva kunobva uye kune kwaanobva. Muchokwadi, ayo akabatana negwara rekuti "kunobva kwaibva" aive positrons, kana maerekitironi akanaka achifamba kubva panobva.

Zvichakadaro, muUnited States mukupera kwezhizha ra1932. Carl David Anderson (4), mwanakomana wevakabva kuSweden, akadzidza mwaranzi yemuchadenga ari mukamuri yegore pasi pesimba remagineti. Mwaranzi yeCosmic inouya kuNyika kubva kunze. Anderson, kuti ave nechokwadi chekutungamira uye kufamba kwezvikamu, mukati mekamuri yakapfuura zvimedu kuburikidza nendiro yesimbi, kwavakarasikirwa nerimwe simba. Musi waNyamavhuvhu 2, akaona nzira, iyo yaakadudzira pasina mubvunzo seyerekitironi yakanaka.

Izvo zvakakosha kucherechedza kuti Dirac akambofanotaura kuvepo kwedzidziso yechinhu chakadaro. Zvisinei, Anderson haana kutevera chero nheyo dzedzidziso muzvidzidzo zvake zvemiranzi ye cosmic. Muchirevo chechinyorwa ichi, akadana kuwanikwa kwake netsaona.

Zvakare, Joliot-Curie aifanira kutsungirira basa risingarambiki, asi akaita imwe tsvakiridzo munzvimbo iyi. Vakaona kuti gamma-ray photon inogona kunyangarika pedyo nenyukiresi inorema, ichiita electron-positron pair, sezviri pachena maererano neEinstein's yakakurumbira formula E = mc2 uye mutemo wekuchengetedza simba uye kukurumidza. Gare gare, Frederick pachake akaratidza kuti pane maitiro ekunyangarika kwe electron-positron pair, zvichiita kuti pave nemagamma quanta maviri. Kuwedzera kune positrons kubva kune erekitironi-positron pairs, vaive nemapositroni kubva mukuita kwenyukireya.

5. Seventh Solvay Conference, 1933

Akagara mumutsara wepamberi: Irene Joliot-Curie (wechipiri kubva kuruboshwe),

Maria Skłodowska-Curie (wechishanu kubva kuruboshwe), Lise Meitner (wechipiri kubva kurudyi).

artificial radioactivity

Kuwanikwa kweartificial radioactivity kwaisava kuita kwepakarepo. Muna Kukadzi 1933, nekubhomba aluminium, fluorine, uyezve sodium ine alpha particles, Joliot akawana neutrons uye isotopes isingazivikanwe. Muna Chikunguru 1933, vakazivisa kuti, nekuvhenekesa aruminiyamu ine alpha particles, havana kucherechedza neutron chete, asiwo positrons. Sekureva kwaIrene naFrederick, ma positrons mukuita kwenyukireya iyi haaigona kunge akaumbwa nekuda kwekuumbwa kwema electron-positron pairs, asi aifanira kubva munyukireya yeatomu.

Seventh Solvay Conference (5) yakaitika muBrussels munaOctober 22-29, 1933. Yakanzi "The Structure and Properties of Atomic Nuclei". Yakapindwa nenyanzvi dzefizikisi 41, kusanganisira nyanzvi dzine mukurumbira mundima iyi pasi rose. Joliot akashuma mhedzisiro yezviedzo zvavo, achiti irradiating boron nealuminium ine alpha rays inoburitsa ingave neutron ine positron kana proton.. Pamusangano uyu Lisa Meitner Akataura kuti mukuedza kumwe chete nealuminium uye fluorine, haana kuwana mhedzisiro yakafanana. Mukududzirwa, haana kugovera maonero evaviri kubva kuParis nezve nyukireya yekwakabva positrons. Zvisinei, paakadzokera kunoshanda muBerlin, akaita zvakare zviedzo izvi, uye musi waNovember 18, mutsamba kuna Joliot-Curie, akabvuma kuti iye zvino, mumaonero ake, positrons inobuda kubva mukati.

Mukuwedzera, musangano uyu Francis Perrin, vezera ravo uye shamwari yakanaka yokuParis, vakataura pamusoro penhau ye<em>positrons. Kubva pakuedza zvaizivikanwa kuti vakawana inoenderera mberi ye positrons, yakafanana neyakasiyana-siyana ye beta particles mukuora kwechisikigo radioactive. Kumwe kuongorora kwesimba re positrons uye neutrons Perrin akasvika pakugumisa kuti kuburitswa kuviri kunofanira kusiyaniswa pano: kutanga, kubuda kwemanyutroni, kunoperekedzwa nekuumbwa kweiyo nucleus isina kugadzikana, uyezve kubuda kwe positrons kubva mumukati uyu.

Mushure memusangano Joliot akamisa zviedzo izvi kwemwedzi miviri. Uye muna December 1933, Perrin akabudisa maonero ake panyaya yacho. Panguva imwecheteyo, zvakare munaDecember Enrico Fermi akakurudzira dzidziso yekuora kwebeta. Izvi zvakashanda sehwaro hwedzidziso yekududzirwa kwezviitiko. Mukutanga kwa1934, vaviri kubva kuguta guru reFrance vakatangazve kuedza kwavo.

Chaizvo musi waNdira 11, China masikati, Frédéric Joliot akatora foiri yealuminium ndokuibhomba nezvidimbu zvealpha kwemaminitsi gumi. Kekutanga, akashandisa Geiger-Muller counter kuti aonekwe, uye kwete fog chamber, sepakutanga. Akashamisika achiona kuti paakabvisa kwaibva alpha particles kubva mufoil, kuverenga kwepositrons hakuna kumira, macounter akaramba achivaratidza, nhamba yavo chete yakadzikira zvakanyanya. Akasarudza hafu yehupenyu kuve maminetsi matatu nemasekonzi gumi nemashanu. Ipapo akaderedza simba rezvikamu zvealpha zvinowira pafoiri nekuisa bhureki remutobvu munzira yavo. Uye yakawana positrons shoma, asi hafu yehupenyu haina kuchinja.

Ipapo akaisa boron uye magnesium kune zviyedzo zvakafanana, uye akawana hafu yehupenyu mune izvi zviedzo zvemaminitsi gumi nemana nemaminetsi 14, zvichiteerana. Zvadaro, kuedza kwakadaro kwakaitwa nehydrogen, lithium, carbon, beryllium, nitrogen, oxygen, fluorine, sodium, calcium, nickel uye sirivheri - asi haana kuona chiitiko chakafanana nealuminium, boron uye magnesium. Kaunda yeGeiger-Muller haisiyanisi pakati pezvimedu zvakanaka uye zvisina kunaka zvinochajwa, saka Frédéric Joliot akasimbisawo kuti inobata nemaerekitironi akanaka. Hunhu hwehunyanzvi hwaive hwakakoshawo mukuyedza uku, kureva, kuvepo kwechitubu chakasimba che alpha particles uye kushandiswa kweansinsitive charged particle counter, senge Geiger-Muller counter.

Sezvakatsanangurwa kare neJoliot-Curie pair, positrons uye neutron zvinoburitswa panguva imwe chete mukucherechedzwa shanduko yenyukireya. Iye zvino, vachitevera mazano aFrancis Perrin uye vachiverenga zvaifungwa naFermi, vaviri vacho vakagumisa kuti nyukireya yokutanga yakagadzira nucleus isina kugadzikana uye neutron, ichiteverwa nebeta pamwe nekuora kweiyo nucleus isina kugadzikana. Saka vaigona kunyora maitiro anotevera:

MaJoliots akacherekedza kuti mhedzisiro yeradioactive isotopes yaive nehupfupi hafu yehupenyu kuti ivepo mune zvakasikwa. Vakazivisa mhedzisiro yavo muna Ndira 15, 1934, mune chinyorwa chakanzi "Rudzi Rutsva rweRadioactivity". Mukutanga kwaKukadzi, vakabudirira mukuziva phosphorus nenitrogen kubva pamaitiro maviri ekutanga kubva pazvishoma zvakaunganidzwa. Nenguva isipi kwakave nehuporofita hwekuti mamwe ma radioactive isotopes anogona kugadzirwa mune nuclear bombardment reactions, zvakare nerubatsiro rwemaproton, ma deuteron nemanyutroni. Muna Kurume, Enrico Fermi akabheja kuti kuita kwakadai kwaizoitwa munguva pfupi uchishandisa manyuturoni. Nenguva isipi akahwina bheji pachake.

Irena naFrederick vakapihwa Mubairo weNobel muChemistry muna 1935 nekuda kwe "kusanganiswa kwezvinhu zvitsva zveradioactive". Kuwanikwa uku kwakagadzira nzira yekugadzirwa kwemaisotopi eradioactive isotopes, ayo akawana akawanda akakosha uye akakosha mashandisirwo mukutanga kutsvaga, mushonga, uye indasitiri.

Chekupedzisira, zvakakodzera kutaura mafizikisi kubva kuUSA, Ernest Lawrence nevaaishanda navo kubva kuBerkeley uye vaongorori vePasadena, pakati pavo paive nePole aive ari painternship. Andrzej Soltan. Kuverengwa kwemapulses nemacounter kwakaonekwa, kunyange zvazvo accelerator yakanga yatomira kushanda. Vaisafarira kuverenga uku. Nekudaro, ivo havana kuziva kuti vaive vachibata nechinhu chitsva chakakosha uye kuti vakangoshaya kuwanikwa kweiyo yakagadzirwa radioactivity ...