Chweba: Iintlobo, iindlela, kunye izicelo. Thermally chweba busebenza - yintoni na le nto?

Chweba - na ukukhutshwa ukukhanya izinto ezithile ukwimeko kubanda kakhulu. Yohluka ukusuka kwimitha lwamaqumrhu ezingqengezelayo, ezifana kweenkuni evuthayo okanye amalahle, i intsimbi etyhidiweyo kunye wire elibaselwe ngumoji umsinga wombane. chweba mhlobo uyabonakala:

• e neon kunye ezijiko izibane, shini screens radar kanye fluoroscopes;
• organic izinto ezifana luminol okanye yilucifen in kwenkanyezi;
• e ngombala ezithile ezisetyenziswa intengiso yangaphandle;
• kunye imibane kunye aurora.

Kuzo zonke ezi nesenzeko komoya ukukhanya ayibangelwa ngokushushubeza umbandela ngasentla lobushushu igumbi, ngoko ibizwa ngokuba ukukhanya. Ixabiso ngayo izinto luminescent kukuba nako kwabo nokutshintsha uhlobo engabonakaliyo yamandla ibe bokukhanya.

Imithombo kunye nenkqubo

chweba kwenzeka ngenxa yokuba izinto Ukunciphisa amandla, umzekelo, ukusuka umthombo yiultraviolet okanye-X-reyi, imiqadi electron, ekudibaneni kwemichiza, njalo njalo. d. Oku kukhokelela kwi athom kweziyobisi kwindawo yimincili. Ekubeni iyahlozinga, imbuyekezo izinto kwimeko yayo yakuqala, kwaye amandla wendele uyakhululwa njengokuba ukukhanya kunye / okanye nobushushu. Le nkqubo ibandakanya kuphela electron engaphandle. ngendlela chweba kuxhomekeke iqondo noguqulo lwamandla excitation ekukhanyeni. Inani lwezixhobo babe intsebenzo ezaneleyo ukusetyenziswa practical, incinci kakhulu.

Chweba kunye incandescence

chweba excitation akazalani ukuya excitation-athom. Xa izinto ezishushu ziqala likhazimle ngenxa kwezibane, athom zabo kwimeko yimincili. Nangona zihamba nokuba bushushu, kwanele ukuba radiation kwenzeka kummandla kude infrared ecacicleyo. Ngenxa yokwanda lobushushu ngokutshintsha nezihlandlo radiation magnetic kummandla ebonakalayo. Kwelinye icala, xa amaqondo obushushu aphezulu kakhulu leyo eyenziwe, umzekelo, kwiityhubhu umothuko, yangqubana atom unokuba namandla kangangokuba electron abazakluleyo kubo kwaye recombine, idangatya ukukhanya. Kulo mzekelo, chweba kunye yale igqengezelayo baba yinto enzima.

ngombala ezibengezelayo kunye nedayi,

ngombala eqhelekileyo kunye nedayi imibala njengoko ibonisa ukuba yinxalenye spectrum leyo Incedisa ithathe. Inxalenye encinane amandla aguqulwa abe bubushushu, kodwa amadlozi elibalulekileyo kwenzeka. Noko ke, ukuba, lo mbala ezibengezelayo sitsala ukukhanya uluhlu kwindawo ethile, kunokuba kukhupha ziluhlaza, yahlukile reflection. Oku kwenzeka ngenxa yeenkqubo ngaphakathi idayi okanye mbala molecule, apho ukukhanya yelanga inokujikwa ibe ezibonakalayo, umzekelo, ukukhanya blue. iindlela ezifana chweba zisetyenziswa kakhulu intengiso yangaphandle kunye kwisiko nemigubo. Kwimeko yokugqibela, i "clarifier" uhlala esikule kungekuphela ukubonakalisa omhlophe, kodwa ukuguqula imitha yelanga ibe oluhlaza, emthubi kokuvumelana ngcono emhlophe.

izifundo okuqala

Nangona imibane Aurora obuvela nkqi kwenkanyezi nomngundo basoloko abawaziyo, amaphononongo chweba lokuqala baqalisa kunye izinto zokwenziwa, xa Vincenzo Kaskariolo esegumbini kunye umkhandi of Bologna (Italy), ngo-1603 g. Umxube shushu of barium sulfate (barite kule fomu, Spar enzima) kunye namalahle. Le umgubo afunyenwe emva lungapholi, ubusuku chweba oluhlaza ukhutshiwe, kunye Kaskariolo waphawula ukuba kubuyiselwa nezikhundla le umgubo kwelanga. Le nto ke igama "lilitye lesafire yokhanyiso ngelanga" okanye sunstone, ngenxa yokuba abenzi bamachiza nethemba ukuba uyakwazi ukujika iintsimbi kwisiseko ibe igolide, uphawu yayo kwelanga. Afterglow iye yabangela umdla izazinzulu ezininzi kwexesha, ukunika izixhobo kunye namanye amagama, kuquka "phosphorus", gama elo elithetha "yenethiwekhi sokukhanya".

Namhlanje igama "phosphorus" lisetyenziswa kuphela element kwemichiza, ngoxa izinto microcrystalline luminescent ngokuba phosphor. "Phosphorus" Kaskariolo, kuyabonakala ukuba, yena emanzini barium. Le phosphor ekhoyo ngokorhwebo wokuqala (1870) waba "ukupeyinta Balmain" - isisombululo ngecalcium emanzini. Ngowe-1866, oko kuchazwa esitalini zinc emanzini phosphor yokuqala ka - enye yezinto ezibalulekileyo iteknoloji.

Omnye izifundo zokuqala zenzululwazi chweba, nto leyo wabonakalaliswa kubola okanye nenyama kunye kwenkanyezi, lwenziwa ISAZINZULU IsiNgesi uRobert Boyle, owathi, nangona wayengazi malunga nemvelaphi zengqo- yale kukhanya, kodwa wabeka ezinye iimpawu ezisisiseko iinkqubo ziyakwazi ngo-1672:

• Zikhanya kubanda;
• kokuba bacinezelwa arhente yemichiza ezifana utywala, zehydrochloric acid kunye ammonia;
• radiation ufuna ukufikelela kwi emoyeni.

Kwiminyaka 1885-1887, wawuqhutywa ukuba izicatshulwa ekrwada ukusuka kwenkanyezi West Indian (pyrophorus) kunye lembaza Foladi xa ixutywe ukukhanya imveliso.

Izinto zokuqala olusebenzayo chemiluminescent baba iikhompawundi zokwenziwa nonbiological ezifana luminol, wafumanisa kunyaka 1928.

Zintsonkothile- and bioluminescence

Uninzi lwe-eneji yakhululwa ekudibaneni kwemichiza, ingakumbi reactions igcwala, na uhlobo ubushushu. Kwezinye reactions, kodwa inxalenye kusetyenziswa ukubangela electron ukuya kumanqanaba aphezulu, kwaye iimolekyuli ezibengezelayo phambi kokuba chemiluminescence (CL). Uphando lubonisa ukuba CL na isenzeko jikelele, kodwa ngamandla chweba incinane kangangokuba ifuna ukusetyenziswa detectors olubuthathaka. Noko ke, ezinye imichiza ebonisa ngokucacileyo CL. Elaziwa kakhulu kwezi luminol, leyo phezu igcwala kunye iperoksayidi yehidrojeni kungaba kukukhanya onamandla blue okanye blue-eluhlaza. Amanye amandla ka CL-izinto - kunye lofin lucigenin. Nangona ukukhanya CL wabo, asingabo bonke bephela olusebenzayo ukuguqula amandla ekhemikhali angene ekukhanyeni, okt. K. Ngaphantsi kwe-1% ye-iimolekyuli kukhutshwe ukukhanya. Ngo-1960 kwafunyaniswa ukuba esters ka oxalic acid, oxidized kwi izinyibilikisi anhydrous phambi iikhompawundi ezibengezelayo kakhulu enuka kukhutshwe ukukhanya okuqaqambileyo kunye nokusebenza-23%.

Bioluminescence uhlobo olulodwa chemiluminescence catalyzed yi enzymes. Imveliso chweba ezi khemikhali uyakwazi ukufikelela-100%, nto leyo ithetha ukuba molecule ngamnye yilucifen reactant ngena esikhupha karhulumente. Zonke namhlanje asabela eyaziwa ziyakwazi catalyzed reactions igcwala esivulekayo phambi komoya.

chweba thermally busebenza

Thermoluminescence uthetha ukuba akukho radiation thermal kodwa ekomelezeni izinto ukukhutshwa ukukhanya, electron leyo sichulumancile ngenxa yobushushu. Thermally kwavusa chweba wazibona kwezinye izimbiwa kunye ingakumbi crystal phosphors emva kokuba yitile ngokukhanya.

photoluminescence

Photoluminescence leyo eyenzeka phantsi amanyathelo okwenzeke radiation magnetic kwi umbandela, ngaba senziwe kuluhlu bokukhanya ngokusebenzisa yiultraviolet ukuya x-reyi kwaye radiation gamma. Xa chweba, kubefundisi ziluhlaza, yokukhanya lobuso ilingana ngokubanzi okanye ngaphezu ngamaza umdla (m. E. ngokulinganayo okanye igunya ngaphantsi). Le umahluko kwamaza ebangelwe inguqu amandla engenayo ibe intlokoma-athom okanye ion. Ngamanye amaxesha, kunye ngamandla laser umqadi, ukukhanya ekhutshwa kunokuba kwamaza elifutshane.

Into yokuba i-PL ibe sichulumancile imisebe yelanga, yafunyanwa ngama yamachiza yaseJamani uJohann Ritter ngo-1801, waphawula ukuba phosphors ukuvutha kuqaqamba kummandla engabonakaliyo inxalenye ezimfusa spectrum, yaye ngaloo ndlela wavula radiation UV. Ukuguqulwa UV ekukhanyeni okubonakalaliswayo kubaluleke kakhulu pfunaka.

Gamma no -x-reyi useza phosphors, kunye nezinye izinto crystalline ukuya chweba karhulumente yinkqubo ionization ilandelwe recombination of elektroni kunye ion, apho kwenzeka chweba. Ukusetyenziswa oko fluoroscopy osetyenziswa ngemitha, kunye zokubala scintillation. Ingxelo yokugqibela ulinganise radiation wesigrike ngqo kwi disc nala phosphor, apho wadibana enombala kunye kumphezulu photomultiplier.

triboluminescence

Xa ziikristale kwezinye izinto, ezifana iswekile, emphefumlweni, yintlantsi ebonakalayo. Kukwanjalo liyasetyenziswa nezinto ezininzi eziphilayo nezingaphiliyo. Zonke ezi ndidi chweba eyenziwe izityholo akhabayo kunye zombane. Yakutshanje eziveliswa imiphezulu ukwahlukana ngoomatshini kwinkqubo crystallization. wokunciphisa Light ke ithatha indawo ngokuthi ngokuchitha - mhlawumbi ngqo phakathi moieties ezi molekyuli, mhlawumbi excitation of chweba yeegesi kufutshane kumphezulu bahlukane.

electroluminescence

Njengoko thermoluminescence, electroluminescence (EL), lo gama iquka iintlobo ezahlukeneyo inkalo eziqhelekileyo chweba yayo loo ukukhanya ophumayo xa ukubhobhoza yombane bayo, ulwelo kunye nezinto eziqinileyo. Ngowe-1752 Bendzhamin Franklin waseka chweba yokumpompoza zombane umbane-aqhubela kudlule emkhathini. Ngowe-1860, isibane obhobhozayo saqala kwaboniswa kwi Royal Society of London. Yena wenza ukukhanya okuqaqambileyo emhlophe ukubhobhoza ombane aphezulu ngokusebenzisa le carbon dioxide ngamandla eliphantsi. izibane ezibengezelayo Modern zisekelwe indibanisela electroluminescence kunye photoluminescence mercury athom sichulumancile yi yombane isibane ukubhobhoza, yemisebe yelanga ezintweni kubo iguqulelwa ningene ekukhanyeni ebonakalayo nge le phosphor.

EL ambona i electrode ngexesha electrolysis ngenxa recombination of ion (ngoko ke uhlobo chemiluminescence). Phantsi yempembelelo intsimi yombane kwiingcamba obhityileyo zinc luminescent emanzini yazingcolisa ukukhanya kwenzeka, nto leyo nezaziwa electroluminescence.

Inani elikhulu zemathiriyeli nekhupha chweba phantsi kweempembelelo electron okukhawulezileyo - diamond, isardiyo, crystal phosphorus kunye ezithile platinum netyuwa ezintsonkothileyo. Lokuqala Isicelo ngokoqobo cathodoluminescence - Oscilloscope (1897). izikrini efanayo usebenzisa phosphors crystalline oluphuculweyo zisetyenziswa shini radars, oscilloscopes kunye iimikroskopu electron.

of radio

izinto Radioactive nga kukhupha amasuntswana alpha (helium nuclei), electron kunye gamma (high-amandla radiation electromagnetic). Imitha chweba - amadangatye sichulumancile yi Radioactive. Xa alpha yamasuntswana bandihlaba crystalline phosphor, zibonakale phantsi neemicroscope yokudanyaza ezincinane. Lo mgaqo usebenzisa yesayensi IsiNgesi Ernest Rutherford, ukungqina ukuba atom unalo engundoqo engundoqo. ipeyinti Self-ezikhanyayo esetyenziselwa iiwotshi kunye nezinye izixhobo zokumakisha zisekelwe kwi-RL. Ziqulethe le phosphor kunye Radioactive, umzekelo okanye eziFihliweyo Radium. Encomekayo chweba yendalo - lo ezimibalabala Aurora: iinkqubo radioactive elangeni ayikhuphi emajukujukwini izihlwele emikhulu elektroni kunye ion. Xa besondela Umhlaba, lentsimi yayo geomagnetic mababuye nezibonda. iinkqubo Gas-kukhululeka umphantsi nomphezulu yeegesi kwaye udale aurora odumileyo.

Chweba: nokwakheka inkqubo

Isidoda yokukhanya okubonakalayo (okt. E. Nge zamaza phakathi 690 NM kunye 400 NM) excitation ifuna amandla, nto leyo ugqibe ubuncinane umthetho Einstein. Energy (E) silingana Planck kaThixo rhoqo (h), xa iphinda phindwe frequency yokukhanya (ν) okanye ngesantya emoyeni (c), bahlulwe kwamaza (λ): E = hν = HC / λ.

Ngenxa yoko, i-eneji efunekayo ukuze excitation isusela evela kilocalories 40 (red) ukuya 60 kcal (for etyheli), kunye calories 80 (ukuya nemfusa) Mol wenkqu nganye. Enye indlela yokubonisa amandla - in volts electron (1 eV = 1,6 × 10 ^-12 IsiNdebele) - ukususela 1.8 ukuya 3.1 eV.

I-eneji excitation idluliselwa elektroni onoxanduva chweba ukuba utsibe ukusuka kumgangatho emhlabeni lowo ephezulu. Ezi meko zimiselwa yimithetho ubucukubhede quantum. iindlela ezahlukeneyo excitation kuxhomekeke enoba kwenzeka atom abangatshatanga kunye molekyuli, okanye izayamaniso molecule e yikristale. Bona iqalwa sisenzo amasuntswana olungongezwanga, ezifana elektroni, unako HIV okanye ziluhlaza.

Amaxesha amaninzi, amandla excitation iphezulu kakhulu kunaleyo kufuneka ukukhulisa ovela ku kwimitha. Umzekelo, phosphor chweba screens crystal kamabonwakude, electron cathode enziwa amandla kwe 25,000 volts. Noko ke, umbala zokukhanyisa ezibengezelayo esiphantse ezizimeleyo amandla yamasuntswana. It iphenjelelwa kwenqanaba imeko nemincili lamaziko yikristale amandla.

izibane ezibengezelayo

Amasuntswana, ngenxa apho kwenzeka chweba - oku electron zangaphandle athom okanye iimolekyuli. Xa izibane ezibengezelayo, ezifana mercury atom iqhutywa phantsi kwempembelelo yamandla 6.7 eV okanye ngaphezulu, ephakamisa omnye electron ezimbini zangaphezulu ukuya kwinqanaba eliphezulu. Emva ukubuyela karhulumente phantsi le umahluko amandla ukhutshiwe njengokuba ukukhanya yelanga kunye ngamaza 185 NM. Inguqu phakathi isiseko kunye kwelinye inqanaba ivelisa ultraviolet radiation kwi 254 NM, nto leyo, ukwedlula abanye phosphor esivelisa ukukhanya okubonakalayo.

Le imisebe kakhulu ngokukodwa koxinzelelo eliphantsi nesigidi (10 ^-5 emoyeni) ezisetyenziswa izibane obhobhozayo igesi xi eliphantsi. Ngoko malunga ne-60% ye-eneji electron iguqulelwa ukukhanya UV monochromatic.

Ngamandla, njalo kwandisa. Spectra akusayi luqulathe igama elinye line ecacicleyo ka 254 NM, kwaye amandla mitha isasazwa ukusuka imigca ecacicleyo ihambelana kumanqanaba ahlukeneyo elektroniki: 303, 313, 334, 366, 405, 436, 546 and 578 NM. izibane mercury xi High zisetyenziselwa ukhanyiso, ekubeni ibonakale 405-546 NM ukukhanya blue-eluhlaza, lo gama iinguqu inxalenye radiation kwi ukukhanya elibomvu usebenzisa phosphor ngenxa amathuba emhlophe.

Xa zegesi anemincili, spectra zabo chweba ukubonisa bands ebanzi; kuphela electron bayavuswa kumanqanaba energy kodwa eshukumayo ngaxeshanye enemincili vibrational kwaye ejikelezayo ye atom kwi yonke. Oku kungenxa yamandla vibrational kwaye ejikelezayo ezi molekyuli 10 ^-2 no-10 ^-4 ze amandla inguqu, leyo dibanisa ukuya ukuchaza ezininzi amacandelo ahlukeneyo kancinane ombala band elinye. Ezi molekyuli ezinkulu kufuneka imicwe eziliqela idlulela, enye uhlobo ngalunye yenguqu. iimolekyuli imisebe isisombululo advantageously ribbonlike ukuba zibangelwa yi impefumlelwano inani elikhulu kakhulu neemolekyuli nemincili kunye iimolekyuli kuphela. Kule molekyuli, njengoko kwi athom ababandakanyekayo chweba electron zangaphandle orbitals eziphilayo.

Fluorescence kunye phosphorescence

Le migomo zingahlukaniswa nje kuphela ngokusekelwe ubude chweba, kodwa indlela yayo kwimveliso. Xa electron sele yitile ukuba urhulumente singlet kunye lokuhlala kuwo 10 ^-8 s, ukusuka apho ngokulula ubuyele emhlabeni, iyeza likhupha amandla alo fluorescence. Ngethuba lenguqu, lo spin akaguquguquki. ithi esisiseko kunye nemincili babe ubuninzi efanayo.

Elektroni, kunjalo, banokuvuselwa kwinqanaba energy eliphezulu (ekuthiwa "i karhulumente triplet yimincili") kunye nonyango wakhe. Xa ukukhanda quantum, le ukuguquka ukusuka triplet kurhulumente ukuya singlet akuvumelekanga, ngako oko, ixesha lobomi babo nokunye okuninzi kakhulu. Ngoko ke, lo chweba kule meko kakhulu ixesha elide; akukho phosphorescence.