Luminescence: mitundu, njira, ndipo ntchito. Thermally analimbikitsa luminescence - ndi chiyani ichi?

Luminescence - ndi umuna wa kuunika ndi zipangizo zina mu boma ndi ozizira. Kumasiyana ndi cheza cha matupi incandescent, monga moto nkhuni kapena malasha, chitsulo chosungunuka ndi waya usavutike ndi magetsi. luminescence umuna zimawonedwa:

• mu Neon ndi fulorosenti nyali, ma TV, zowonetsera Rada ndi fluoroscopes;
• mu zinthu organic monga luminol kapena luciferin mu ziphaniphani;
• mu inki linalake malonda panja;
• ndi mphezi ndi Aurora.

Mu zochitika zonsezi umuna kuwala si chifukwa cha Kutentha nkhani pamwamba firiji, kotero kuti getsi losatentha. The lothandizadi zipangizo luminescent ndi luso lawo kusintha mawonekedwe yakumwamba ya mphamvu mu kuwala kuwoneka.

Magwero ndi ndondomeko

luminescence chodabwitsa kumachitika chifukwa cha mphamvu mayamwidwe chuma, mwachitsanzo, gwero la ultraviolet kapena X-ray, elekitironi matabwa, zochita mankhwala, ndi zina zotero. d. Izi zimachititsa maatomu yachabechabe zimachitika okondwa. Popeza akhala wosakhazikika, akadzabweranso chuma uliri pachiyambi, ndi mphamvu imatsala monga kuwala ndi / kapena kutentha. ndondomeko amatenda okha ma elekitironi akunja. luminescence Mwachangu zimadalira mlingo wa kutembenuka kwa malemeredwe mphamvu mu kuwala. chiwerengero cha zipangizo kuti ndi ntchito zokwanira kugwiritsa ntchito, ndi ochepa.

Luminescence ndi incandescence

luminescence malemeredwe si zokhudzana ndi malemeredwe maatomu. Pamene zipangizo otentha anayamba kuwala chifukwa cha mababu, maatomu awo ali mu mkhalidwe okondwa. Ngakhale kunjenjemera ngakhale firiji, ndi kokwanira kuti cheza inkachitika mu kutali infuraredi kawalidwe dera. Ndi kukula kutentha kumasintha pafupipafupi cheza mu atomu m'dera kuwoneka. Komano, pa kutentha kwambiri amene kwaiye Mwachitsanzo, machubu mantha, mwansanga atomiki akhoza kukhala wamphamvu kuti ma elekitironi anasiyanitsidwa iwo ndi recombine, emitting kuwala. Pankhaniyi, luminescence ndi incandescent kukhala osiyana.

inki fulorosenti ndi utoto,

inki ochiritsira ndi nsalu ndi mtundu akamaganizira gawo la sipekitiramu amene ali wowonjezera odzipereka. A gawo laling'ono la mphamvu ndi n'kukhala kutentha, koma umuna kwambiri amapezeka. Ngati Komabe, pigment fulorosenti zimatenga kuwala osiyanasiyana dera, zikhoza zimatulutsa photons, wosiyana chinyezimiritso. Izi zimachitika chifukwa cha njira mu utoto kapena pigment molekyulu, imene kuwala ultraviolet zikhoza kusinthidwa n'kukhala kuonekera Mwachitsanzo, buluu kuwala. njira zimenezi luminescence ntchito malonda panja ndi kusamba ufa. Mu Zikatero, "clarifier" amakhalabe minofu osati kuti tionetse woyera, komanso kutembenuza ultraviolet poizoniyu mu buluu, chikasu akulipira ndi utithandize whiteness.

maphunziro oyambirira

Ngakhale mphezi Aurora ndi wosasamala chowala ya ziphaniphani bowa nthawi zonse kudziwika kwa anthu oyamba luminescence maphunziro anayamba ndi zinthu zenizeni, pamene Vincenzo Kaskariolo alchemist ndi yokonza nsapato za Bologna (Italy), mu 1603 g. Mkangano osakaniza barium sulphate (barite mu mawonekedwe, spar katundu) ndi malasha. The ufa analandira pambuyo kuzirala, usiku buluu luminescence panamveka, ndi Kaskariolo anaona kuti angabwezeretsedwe ndi kugonjera ufa dzuwa. thunthu dzina lake "lapis solaris" kapena sunstone, chifukwa asayansi ankaganiza kuti akhoza kutembenukira zitsulo m'munsi mu golide, chizindikiro cha ndilo dzuwa. Kuwala kotsalira m'mbuyo wachititsa chidwi asayansi ambiri nyengo, kupereka katundu ndi maina ena, kuphatikizapo "phosphorous" kutanthauza "chotengera cha kuunika".

dzina "phosphorous" Lero ntchito okha zinthu mankhwala, pamene chuma microcrystalline luminescent wotchedwa phosphor. "Phosphorus" Kaskariolo, zikuoneka, anali barium sulfide. Woyamba malonda zilipo phosphor (1870) anakhala "kujambula Balmain" - njira ya sulfide calcium. Mu 1866, limafotokonzera woyamba khola nthaka sulfide phosphor wa - imodzi yofunika kwambiri zipangizo zamakono.

Mmodzi wa maphunziro oyamba sayansi luminescence, amene akuwonekera pa lawola matabwa kapena thupi ndi ziphaniphani, unkachitika mu 1672 ndi English wasayansi Robert Boyle, ngakhale kuti samadziwa za chiyambi amuzolengedwa kuunika, koma anapereka zina zimatha zofunika kachitidwe bioluminescent:

• Kuwala ozizira;
• zikhoza kuletsedwa ndi wothandizila mankhwala monga mowa, acid amathiridwa ndi amoniya;
• cheza amafuna kupeza mlengalenga.

Mu zaka 1885-1887, izo unkachitika kuti akupanga yosakongola kwa ziphaniphani West Indian (pyrophorus) ndi nsombayi Foladi pamene osokonezeka zokolola kuwala.

Woyamba ogwira zipangizo chemiluminescent anali nonbiological kupanga mankhwala monga luminol, anapeza mu chaka cha 1928.

Chemi- ndi bioluminescence

Ambiri mwa mphamvu anamasulidwa mu zochita mankhwala, makamaka zosiyanasiyana makutidwe ndi okosijeni, ali mawonekedwe a kutentha. Ena zochita, koma gawo ntchito chimwemwe ma elekitironi mpaka milingo apamwamba, ndi tinthu fulorosenti pamaso pa chemiluminescence (CL). Kafukufuku akusonyeza kuti CL ndi chodabwitsa chilengedwe, koma luminescence mwamphamvu ndi ang'onoang'ono kwambiri motero kuti pamafunika ntchito zoyesera tcheru. Komabe, ena mwa mankhwala kuti aonetse omveka CL. Odziwika kwambiri awa ndi luminol, lomwe pa makutidwe ndi okosijeni ndi wa hydrogen peroxide akhoza kudzipereka wamphamvu buluu kapena buluu wobiriwira kuwala. mphamvu zina za CL-zinthu - ndi lucigenin lofin. Ngakhale CL awo kuwala, si onse ogwira pa akatembenuka mphamvu mankhwala mu kuwala, mwachitsanzo. K. Pasanathe 1% ya mamolekyulu ndi zimatulutsa kuwala. Mu 1960 izo anapezeka kuti esters asidi oxalic, oxidized mu solvents anhydrous pamaso pa mankhwala kwambiri fulorosenti onunkhira zimatulutsa kuwala ndi dzuwa la 23%.

Bioluminescence ndi mtundu wapadera wa chemiluminescence catalyzed ndi michere. The luminescence linanena bungwe la motero angafikire 100%, kutanthauza kuti molekyu iliyonse ya luciferin reactant akulowa emitting boma. Onse odziŵika lerolino bioluminescent anachita catalyzed zochita makutidwe ndi okosijeni zikuchitika mu kukhalapo kwa mpweya.

thermally analimbikitsa luminescence

Thermoluminescence chikutanthauza kuti palibe cheza matenthedwe koma kulimbitsa kuwala umuna zipangizo, ndi ma elekitironi amene wokonda kutentha. Thermally analimbikitsa luminescence anaona ena mchere makamaka phosphors galasi pambuyo anali wokonda kuwala.

photoluminescence

Photoluminescence amene amapezeka pansi zochita za mu atomu cheza zinachitika pa zinthu, zikhoza kupangidwa mu osiyanasiyana kuwala kuonekera mwa ultraviolet kuti x-ray ndi cheza Popanga madzi a gamma. Mu luminescence, anachititsa ndi photons, timaganiza za panamveka kuwala zambiri wofanana kapena wamkulu kuposa timaganiza za zosangalatsa (m. E. Wofanana kapena mphamvu zochepa). Kusiyana mu timaganiza chifukwa cha kusintha kwa mphamvu lilinkudza mu Phokoso maatomu kapena ayoni. Nthawi zina, ndi tima laser mtengo, panamveka kuwala akhoza kukhala lalifupi timaganiza.

chakuti PL akhale osangalala ndi cheza ultraviolet, anatulukira ndi German sayansi Johann Ritter mu 1801. Iye ananena kuti phosphors kuwala kwambiri mu dera yakumwamba ya gawo wofiirira a sipekitiramu, motero anatsegula dzuwa limakhala lamphamvu. Kutembenuka kwa UV kuwala kuonekera ndi zofunika kwambiri zothandiza.

Popanga madzi a gamma ndi x-ray chimwemwe phosphors ndi zinthu zina crystalline kwa luminescence boma ndi ndondomeko ionization akutsatiridwa ndi recombination wa ma elekitironi ndi ayoni, umene luminescence amapezeka. Ntchito ndi mu fluoroscopy ntchito Radiology, ndi scintillation owerengera. Mbiri otsiriza nuyese Popanga madzi a gamma cheza imatsogoleredwa pa chimbale TACHIMATA ndi phosphor amene ali mu kukhudzana kuwala ndi padziko photomultiplier lapansi.

triboluminescence

Pamene timibulu ena zinthu, monga dzuwa, wophwanyidwa, zooneka kuthetheka. Womwewo anati mu zinthu zambiri organic ndi zochita kupanga. mitundu yonse ya luminescence kwaiye zabwino ndi zoipa milandu magetsi. Recent umatulutsa pamalo makina kulekana mu ndondomeko crystallization. Kuwala umuna ndiye kumachitika lililonse - kaya mwachindunji pakati pa moieties wa mamolekyulu, mwina kudzera malemeredwe wa luminescence mpweya wa pafupi pamwamba kulekanitsidwa.

electroluminescence

Monga thermoluminescence electroluminescence (EL), liwu zikuphatikizapo zosiyanasiyana luminescence Mbali wamba chimene kuti kuwunika panamveka pamene kumaliseche magetsi mu mpweya, zakumwa ndi zipangizo olimba. Mu 1752 Bendzhamin Franklin anakhazikitsa luminescence mphezi chovutika kumaliseche magetsi kudzera m'mlengalenga. Mu 1860, a kumaliseche nyale anali woyamba taonera mu Royal Society of London. Iye anabereka kuwala woyera ndi voteji kumaliseche mkulu kudzera mpweya pa mochedwerako. nyali fulorosenti Modern zochokera osakaniza electroluminescence ndi photoluminescence Mercury maatomu wokonda magetsi kumaliseche nyali, ndi cheza ultraviolet panamveka mwa iwo n'kukhala kuwala kuonekera kudzera phosphor lapansi.

EL anamuona maelekitirodi pa electrolysis chifukwa recombination wa ayoni (ndiponso mtundu wa chemiluminescence). Mothandizidwa munda magetsi mu zigawo zonyalazo luminescent nthaka sulfide umuna kuwala zikachitika, umene umatchedwanso electroluminescence.

A ambiri zipangizo limatulutsa luminescence mchikakamizo cha ma elekitironi inapita - diamondi, rube, phosphorous galasi ndi zina zovuta pulatinamu mchere. Woyamba othandiza ntchito cathodoluminescence - Oscilloscope (1897). zowonetsera ofanana ntchito bwino crystalline phosphors ntchito matelevizioni, radars, oscilloscopes ndi elekitironi microscopes.

wailesi

zinthu nyukiliya angathe zimatulutsa Alpha particles (helium mtima), ma elekitironi ndi Popanga madzi a gamma cheza (a mkulu-mphamvu mu atomu cheza). Cheza luminescence - ndi chowala wokonda thunthu nyukiliya. Pamene Alpha tinthu alipo crystalline phosphor, zooneka pansi pa maso kukulowa ting'onoting'ono. Mfundo imeneyi ntchito English sayansi Ernest Rutherford, kutsimikizira kuti atomu ali pakati chapakati. Self-wowala utoto ntchito chodetsa ulonda ndi zipangizo zina zochokera RL. Iwo zigwirizana wa phosphor ndi thunthu nyukiliya Mwachitsanzo tritium kapena Analandira. Chidwi zachilengedwe luminescence - ndi Aurora borealis: njira nyukiliya pa dzuwa zimatulutsa mu malo misa yaikulu ma elekitironi ndi ayoni. Pamene ankayandikira Earth munda wake geomagnetic kuwalimbikitsa kuti mitengoyo. njira gasi kumaliseche mu zigawo chapamwamba ya mpweya ndi kulenga Aurora wotchuka.

Luminescence: sayansi ya ndondomekoyi

Umuna wa owoneka kuunika (ie. E. Ndi adziwana dzulo pakati 690 nm 400 nm) malemeredwe amafuna mphamvu, amene anatsimikiza pa malamulo osachepera Einstein. Mphamvu (E) ndi wofanana Planck mosaleka (h), kuchulukitsa ndi pafupipafupi kuwala (ν) kapena liwiro lake mu zingalowe ndi (c), anagawa ndi timaganiza (λ): E = hν = HC / λ.

Choncho, mphamvu malemeredwe ndi ranges ku kilocalories 40 (kwa wofiira) 60 kcal (kwa yellow), ndi zopatsa mphamvu 80 (kuti wofiirira) pa mol wa mankhwala. Njira ina yosonyeza mphamvu - mu volts elekitironi (1 EV = 1,6 × 10 ^-12 erg) - kuchokera 1.8 kuti 3.1 EV.

The mphamvu malemeredwe ndi kunditumiza ku ma elekitironi amachititsa luminescence kuti kudumpha mlingo ake odyetserako kwa munthu wapamwamba. zinthu izi ofunitsitsa ndi malamulo a kwadzidzidzi zimango. njira zosiyanasiyana malemeredwe zikudalira kumachitika mu ma atomu limodzi ndi mamolekyulu, kapena osakaniza a mamolekyulu mu galasi lapansi. Iwo anayambika ndi zochita za particles inapita patsogolo, monga ma elekitironi, ayoni zabwino kapena photons.

Nthawi zambiri, mphamvu malemeredwe ndi apamwamba kwambiri kuposa chofunika kufunsa elekitironi kuti cheza. Mwachitsanzo, phosphor luminescence galasi TV zowonetsera, cathode ma elekitironi opangidwa ndi mphamvu zikutanthauza okwana 25,000 volts. Komabe, mtundu wa kuwala fulorosenti Pafupifupi osadalira pa mphamvu tinthu. Iwo zimakhudza mlingo wa boma okondwa wa malo galasi mphamvu.

nyali fulorosenti

The particles, chifukwa chimene luminescence amapezeka - ichi ma elekitironi kunja kwa maatomu kapena mamolekyulu. Mu nyali fulorosenti, monga mankhwala enaake atomu adapirikitsidwira mchikakamizo cha mphamvu 6.7 EV kapena zambiri, kukweza umodzi wa ma elekitironi awiri akunja pa mlingo wokwererapo. Atabwerako ake kuti boma pansi kusiyana mu mphamvu panamveka monga kuwala ultraviolet ndi timaganiza za 185 nm. Kusintha pakati m'munsi ndi mlingo wina umabala cheza ultraviolet pa 254 nm, limene pamapeto, kodi chimwemwe ena phosphor ikuyambitsa owoneka kuunika.

kuwala kwa mtundu umenewu makamaka kwambiri pa otsika kuthamanga Mercury nthuzi (10 ^-5 mlengalenga) ntchito mpweya kumaliseche nyali ya mochedwerako. Pafupifupi 60% ya elekitironi mphamvu n'kukhala ndi monochromatic UV kuwala.

Pa kuthamanga, pafupipafupi kumawonjezera. Makulidwe salinso zigwirizana mzere umodzi kawalidwe a 254 nm, ndi cheza mphamvu ndi anagawira zifukwa kawalidwe lolingana magulu a pakompyuta: 303, 313, 334, 366, 405, 436, 546 ndi 578 nm. Kuthamanga Mercury nyali ntchito zofukiza, kuyambira zooneka 405-546 nm buluu wobiriwira kuwala, pamene yosintha gawo cheza mu kuwala kofiira ntchito phosphor chifukwa akutembenukira woyera.

Pamene mamolekyulu mpweya ndi okondwa, luminescence makulidwe awo amasonyeza magulu yotakata; osati ma elekitironi yekha aukitsidwa kwa milingo mphamvu apamwamba koma imodzi okondwa vibrational ndi rotational zoyenda wa maatomu pa lonse. Ichi ndi chifukwa vibrational ndi rotational mphamvu ya mamolekyulu ndi 10 ^-2 ndi 10 ^-4 wa mphamvu kusintha, amene aphatikize kumasulila ndi kuchuluka kwa zigawo yosiyaniranapo timaganiza za gulu limodzi. Mamolekyulu zazikulu ndi toyalana n'kupanga angapo, aliyense mtundu wa kusintha. Cheza mamolekyulu mu njira advantageously ribbonlike kuti chifukwa zimachitika kwa chiwerengero ndi lalikulu la tinthu okondwa ndi tizidutswa zosungunulira. Mu mamolekyulu, monga mu ma atomu nawo luminescence ma elekitironi kunja kwa orbitals maselo.

Kuwala ndi phosphorescence

mawu awa akhoza kuwasiyanitsa osati potengera nthawi ya luminescence, komanso njira zake kupanga. Pamene elekitironi inayake poona kuti boma singlet ndi ulamuliro m'menemo 10 ^-8 m, amene mosavuta udzabwerera kunthaka, thunthu limatulutsa mphamvu yake kuwala. Pa kusintha, ndi sapota sasintha. Kuweta ndi okondwa limati ndi multiplicity ofanana.

Elekitironi Komabe, adzaukitsidwa kuti mlingo wapamwamba mphamvu (otchedwa "ndi okondwa triplet boma") ndi mankhwala wake. Mu zimango kwadzidzidzi, ndi kusintha kwa boma triplet kuti singlet analetsa, choncho, nthawi ya moyo wawo kwambiri. Choncho, luminescence Pankhaniyi zambiri Pomalizira: pali phosphorescence.