Kune mamwe mazwi anounza nyonganiso mumutauro wemazuva ese. Pakati pemazwi aya tine luminescence, fluorescence uye phosphorescence. Matemu akaenzana here? Zvakasiyana sei uye chimwe nechimwe chinorevei?
Tichaona zvese izvi muchinyorwa chino, saka usazvipotse.
Chii chinonzi luminescence
Izwi rokuti luminescence rinoreva kubudiswa kwechiedza. Munharaunda yedu, zvinhu zvizhinji zvinobudisa chiedza nekuda kwesimba ravanowana kubva kuzuva, iro Ndiro rakajeka zvikuru rinoonekwa kwatiri. Kusiyana nemwedzi, unoita sokuti unobudisa chiedza, iwo unotoratidza chiedza chezuva, uchishanda zvakafanana negirazi rebwe guru. Kuti unzwisise zviri nani kuti luminescence inoshanda sei muzvinhu zvakasiyana, unogona kubvunza kukanganisa kwezviitiko zvenyeredzi pane luminescence.
Chaizvoizvo, kune matatu makuru marudzi e luminescence: fluorescence, phosphorescence uye chemiluminescence. Pakati pavo, fluorescence uye phosphorescence inorondedzerwa semhando dze photoluminescence. Musiyano pakati pe photoluminescence uye chemiluminescence uri mukugadzirisa kushandiswa kwe luminescence; Mu photoluminescence, chiedza chinoshanda sechinhu chinokonzera, asi mu chemiluminescence, kemikari inogadzirisa inotanga kubuda kwechiedza.
Zvese zviri zviviri fluorescence uye phosphorescence, ari mafomu ephotoluminescence, zvinoenderana nekugona kwechinhu kutora mwenje uye wozoiburitsa pakareba wavelength, zvichiratidza kudzikiswa kwesimba. Zvisinei, Nguva yekuita izvi inosiyana zvakanyanya. Mukuita kwefluorescent, kubuda kwechiedza kunoitika pakarepo uye kunongoonekwa chete apo mwenje unoramba uchishanda (senge ultraviolet mwenje).
Kusiyana neizvi, maitiro ephosphorescent anobvumira zvinhu kuti zvichengetedze simba rakanyura, zvichiita kuti ribudise chiedza gare gare, zvichiita kuti kupenya kunopfuurira kunyange mushure mokunge chiedza chadzimwa. Nokudaro, kana luminescence ikanyangarika pakarepo, inorondedzerwa se fluorescence; Kana ikaramba iripo, inozivikanwa se phosphorescence; uye kana ichida makemikari kuita kuti ishande, inonzi chemiluminescence.
Mienzaniso yeizvi inogona kuwanikwa mune zvakasikwa zviitiko uye tekinoroji mashandisiro, senge in fluorescent uye phosphorescent zvinhu. Semuenzaniso, munhu anogona kufungidzira kirabhu yehusiku umo machira uye mazino anopenya pasi pechiedza dema (fluorescence), chiratidzo chekubuda chekukurumidzira chinopenya chiedza (phosphorescence), uye matanda anopenya anoburitsawo kuvhenekera (chemiluminescence). Zvakare mukumaka kwezvinhu uye mune zvidzidzo zvesainzi, uko musiyano wenguva ye luminescence yakakosha.
Fluorescence
Zvishandiso zvinoburitsa mwenje ipapo zvinodaidzwa kuti fluorescent. Muzvinhu izvi, maatomu anotora simba, zvichiita kuti vapinde mune "mafaro" mamiriro. Vachidzokera kumugariro wavo wenguva dzose munguva ingangoita zana rezviuru zvesekondi (kubva pa10 ^-9 kusvika ku10 ^-6 masekonzi), vanobudisa simba iri muchimiro chetunhu tuduku-duku kechiedza chinozivikanwa semafotoni.
Kutaura zviri pamutemo, Fluorescence inzira inopenya umo maerekitironi anofadza Ivo vanopfuura kubva pasi pasi inonakidza mamiriro (S1) kuenda pasi pasi (S0). Munguva yeshanduko iyi, maerekitironi anobvisa rimwe resimba rayo kuburikidza nekuzorora kwekudengenyeka, zvichiita kuti photon inobudiswa iite kuderedza simba uye, naizvozvo, kureba kwewavelength.
Nezve mashandisirwo anoshanda uye mienzaniso yefluorescence, unogona kureva "Zvishandiso uye mashandisiro efluorescence musainzi uye tekinoroji".
Phosphorescence
Kuti unzwisise mutsauko uripo pakati pefluorescence uye phosphorescence, zvinodikanwa kuongorora muchidimbu pfungwa ye electron spin. Spin inomiririra hunhu hwakakosha hweerekitironi, ichiita serudzi rweangular manyawi inokanganisa maitiro ayo mukati memunda wemagetsi. Ichi chivakwa chinogona chete kutora kukosha kwe½ uye chinogona kuratidza kumusoro kana kudzika kutaridzika. Mukati meiyo orbital yakafanana yeatomu, maerekitironi anogara achiratidza antiparallel spin kana ari singlet ground state (S0). Pakukwidziridzwa kune imwe nyika ine mafaro, erekitironi inoramba ichitenderera, zvichikonzera kuumbwa kweiyo singlet inonakidzwa mamiriro (S1), apo ese ari maviri spin orientation anoramba akabatana mune antiparallel configuration. Zvakakosha kuziva kuti maitiro ese ekuzorodza anoenderana nefluorescence ari spin-neutral, kuve nechokwadi chekuti electron spin orientation inochengetedzwa nguva dzese.
Muchiitiko che phosphorescence, Maitiro acho anosiyana zvakanyanya, sezvo anosanganisira shanduko pakati penyika dzine akasiyana spin orientation.. Shanduko dzekukurumidza (kubva pa10 ^ -11 kusvika 10 ^ -6 masekonzi) dzinoitika pakati pemasisitimu anopfuura kubva ku singlet excited state (S1) kuenda kune inergetically inofarirwa triplet excited state (T1). Kuchinja uku kunoguma nekudzokera shure kwe electron spin; Izvo zvinokonzeresa nyika zvinoratidzwa ne parallel spins pamaerekitironi ese uye anoiswa seanogoneka. Muchiitiko ichi, kusununguka kunoitika ne phosphorescence, iyo inotungamirira kune imwe kushanduka kwe electron spin uye kunotevera kubudiswa kwe photon.
Shanduko yekudzokera kune yakasununguka singlet state (S0) inogona kuitika mushure mekunonoka kwenguva refu (kusiyana kubva ku10 ^ -3 kusvika kune anopfuura 100 masekonzi). Munguva iyi yekuzorora, nzira dzisiri dzeradiative dzinoshandisa simba rakawanda mukuzorora kwephosphorescent zvichienzaniswa nefluorescence, zvichikonzera mutsauko mukuru wesimba pakati peakatorwa uye akabudiswa mafotoni uye, nekudaro, shanduko yakakura muwavelength. Zvinonakidza kuona kuti mutsauko muchimiro cheatomu chezvishandiso unokonzera sei misiyano iyi muchiitiko che luminescence.
Excitation uye emission spectra
Luminescence inoitika apo maerekitironi echinhu anenge anakidzwa nekutora mafotoni, zvichizoburitsa simba iroro muchimiro chemwaranzi. Mune zvimwe zviitiko, Mwaranzi inoburitswa inogona kuve nemaphoton ane simba rakafanana uye wavelength seaya akabatwa; Ichi chiitiko chinozivikanwa se resonance fluorescence. Kazhinji, mwaranzi inoburitswa ine yakarebesa wavelength, inoratidza yakaderera simba kana ichienzaniswa neyakatorwa mafotoni.
Iyi shanduko kune yakareba wavelengths inozivikanwa seStokes shift. Kana maerekitironi achifadzwa nemwaranzi pfupi, isingaonekwe, anokwira kumatunhu esimba repamusoro. Pakudzokera kumugariro wadzo wepakutanga, dzinobudisa chiedza chinooneka chine urefu hwakafanana, kuratidzira resonance fluorescence. Zvisinei, maerekitironi anofara aya anogonawo kudzoka kune imwe simba repakati, zvichikonzera kubuda kwephoton inopenya inotakura simba shoma pane iro remanyawi ekutanga. Nzira iyi, kana yakakonzerwa nechiedza che ultraviolet, inowanzoratidza se fluorescence mukati memutambo unooneka. Panyaya yezvigadzirwa zvephosphorescent, pane kunonoka pakati pekuputika kwema electrons kusvika kune simba repamusoro uye kudzokera kumamiriro epasi.
Chinhu chinonakidza chekucherechedza ndechekuti kusimba uye ruvara rwechiedza chakabudiswa zvinoenderana nechinhu uye excitation wavelength, iyo yakakosha mukugadzirwa kwezvinhu zvefluorescent uye phosphorescent. Hukama huri pakati pekunakidzwa uye emission wavelengths, inozivikanwa sekunakidzwa uye emission spectra, kiyi yekunzwisisa kuti izvi zvinoitika sei uye riini.
Izvo zvakakosha kuti uzive kuti emission wavelength haibvi pane excitation wavelength, kunze kwezviitiko apo zvinhu zvine akawanda luminescence mechanisms. Nekuda kweizvozvo, zvicherwa zvinoratidza kugona kwakasiyana kutora ultraviolet mwenje pane chaiyo wavelengths; mamwe fluoresce pasi pepfupi-wavelength ultraviolet mwenje, nepo mamwe fluoresce pasi pemafungu akareba, uye mamwe anoratidza kujeka fluorescence. Rudzi rwechiedza chakaburitswa kazhinji rinosiyana zvakanyanya neakasiyana excitation wavelengths.
Kuitika kwezviitiko izvi hakungogumiri pakushandiswa kwemwaranzi ye ultraviolet; asi, kufara kunogona kuwanikwa nemwaranzi chero ipi zvayo ine simba rakakodzera. Semuyenzaniso, X-rays inokwanisa kukonzera fluorescence muzvinhu zvakasiyana, mazhinji ayo anopindurawo kumhando dzakasiyana dzemwaranzi. Magnesium tungstate, semuenzaniso, inoratidza kunzwa kunenge kwemwaranzi yese ine wavelengths ipfupi kupfuura 300 nm, inosanganisira zvese zviri zviviri ultraviolet uye X-ray spectra. Uyezve, zvimwe zvinhu zvinogona kunakidzwa zviri nyore nemaerekitironi, sezvinoratidzwa nephosphors inoshandiswa mumachubhu eterevhizheni.
Uye izvi zviitiko zvinobatana sei nezvimwe zviitiko zvakasikwa?
Kunzwisisa mutsauko uripo pakati pe luminescence, fluorescence uye phosphorescence kunobatsirawo kunzwisisa zvakasikwa zviitiko senge. Cirrus cloud layers nezvimwe zviitiko zvemuchadenga. Ruzivo urwu runopfumisa kududzirwa kwechiedza chechiedza uye kupindirana kwechiedza nezvinhu zvakasiyana munzvimbo yedu, pamwe nekuvhura musuwo wezvitsva zvesainzi uye tekinoroji. Kuziva kuti izvi zvinoitika sei uye kuti ndeapi mamiriro anozvifarira zvinogona kuve kiyi yekufambira mberi munzvimbo dzakaita semineralogy, nyeredzi, uye biomedicine.
