Vim li cas cov xim ploj mus hauv qab lub hnub?

Vim li cas cov xim pleev xim thiaj ploj mus thaum lub hnub? Ua ntej peb nkag siab qhov laj thawj, peb yuav tsum paub ua ntej tias "kev tiv taus hnub" yog dab tsi.

Kev Ruaj Ntseg ntawm Lub Hnub: hais txog lub peev xwm ntawm cov xim pleev kom khaws nws cov xim qub thaum raug tshav ntuj. Raws li cov cai dav dav, kev txiav txim siab ntawm kev ruaj ntseg ntawm lub hnub yog raws li lub hnub. Txhawm rau kom yooj yim tswj hwm hauv chav kuaj, cov khoom siv teeb pom kev zoo feem ntau siv thiab calibrated yog tias tsim nyog. Cov khoom siv teeb pom kev zoo feem ntau yog hernia teeb thiab charcoal arc teeb. Nyob rau hauv lub teeb irradiation, cov xim pleev nqus lub zog teeb, thiab qib zog ntawm cov xim pleev yog nyob rau hauv lub xeev zoo siab. Lub kaw lus xim ntawm cov xim pleev hloov pauv lossis raug rhuav tshem, ua rau cov xim pleev lwj thiab discoloration lossis fading.

1, Qhov cuam tshuam ntawm lub teeb rau kev tsim cov xim

Thaum lub molecule zas xim nqus lub zog ntawm photon, nws yuav ua rau cov electrons sab nraud ntawm lub molecule hloov pauv ntawm lub xeev av mus rau lub xeev zoo siab.

Raws li lawv cov qauv sib txawv, cov xim zas tuaj yeem dhau los ntawm cov txheej txheem sib txawv hauv qab kev ua ntawm lub teeb nthwv dej ntawm ntau qhov wavelengths, suav nrog π→π *, n→π *, CT (them nqi hloov), S→S (xeev singlet), S→T (xeev triplet), xeev av→ xeev zoo siab, thiab xeev av→ xeev thib ob zoo siab. Lub xeev av ntawm lub xeev singlet yog sau ua S0, thiab lub xeev thib ob zoo siab singlet yog sau ua S1 thiab S2, raws li. Lub xeev triplet sib xws yog sawv cev los ntawm T0, T1, thiab T2.

Thaum lub sijhawm ua kom muaj zog, cov xim zas xim raug ua kom zoo siab rau hauv cov xeev electron excited nrog ntau qib zog vibrational. Lawv cov qib zog vibrational sai sai txo qis, hloov lub zog mus rau hauv cua sov thiab dissipating nws. Cov txheej txheem ntawm kev txo qis zog no hu ua vibrational passivation. Thaum lub sijhawm ua kom muaj zog vibration, lub xeev S2 excited nrog qib zog vibration qis kuj tseem yuav hloov mus rau hauv lub xeev S1 excited nrog qib zog vibration siab dua, thiab txuas ntxiv mus rau hauv kev ua kom muaj zog vibration. Ua li no, lub xeev S2 excited nrog qib zog siab dua sai sai hloov mus rau hauv lub xeev S1 excited nrog qib zog vibrational qis dua.

Qhov kev hloov pauv ntawm S2 thiab S1 lub xeev hluav taws xob nyob rau hauv qhov xwm txheej ntawm kev sib tshuam sib npaug zog tsis cuam tshuam nrog kev hloov pauv hauv electron spin multiplicity, thiab hu ua kev hloov pauv sab hauv. Kuj tseem muaj kev hloov pauv ntawm singlet thiab triplet xeev, los ntawm S1 mus rau T1 lub xeev zoo siab. Hom kev hloov pauv ntawm lub xeev hluav taws xob no nrog rau kev hloov pauv electron spin multiplicity nyob rau hauv qhov xwm txheej sib tshuam sib npaug zog hu ua intersystem crossing. Vim yog qhov "txwv tsis pub" ntawm electron spin selectivity, tus nqi ntawm intersystem crossing feem ntau yog qis dua.

Cov tshuaj zas xim uas muaj zog zuj zus raug cov tshuaj tiv thaiv photochemical nrog lwm cov tshuaj, ua rau cov xim ploj mus thiab cov fibers tsis zoo.

2, Cov yam ntxwv cuam tshuam rau lub teeb ci ntsa iab ntawm cov xim pleev xim

1. Qhov ntev ntawm lub teeb thiab lub teeb ci ntsa iab;

2. Tej yam ib puag ncig;

3. Cov khoom siv tshuaj lom neeg thiab cov qauv kev teeb tsa ntawm cov fibers;

4. Lub zog sib txuas ntawm cov xim zas thiab cov fiber;

5. Cov qauv tshuaj ntawm cov xim pleev xim;

6. Cov xim zas thiab cov xwm txheej sib sau ua ke;

7. Qhov cuam tshuam ntawm cov hws dag rau qhov ploj ntawm cov xim;

8. Qhov cuam tshuam ntawm cov khoom ntxiv.

3, Cov txheej txheem rau kev txhim kho lub hnub ci ntawm cov xim pleev xim

1. Txhim kho cov qauv xim kom txo qhov cuam tshuam rau lub kaw lus xim xim thaum siv lub zog teeb, yog li khaws cov xim qub; Feem ntau hu ua cov xim tiv thaiv hnub ci siab. Hom xim no feem ntau kim dua li cov xim ib txwm muaj, thiab rau cov ntaub uas xav tau tshav ntuj ntau, thawj kauj ruam yuav tsum yog xaiv cov xim.

2. Yog tias ntaub twb tau pleev xim lawm tab sis lub hnub tsis ua raws li qhov yuav tsum tau ua, cov khoom ntxiv kuj tseem siv tau los txhim kho nws. Ntxiv cov khoom ntxiv tsim nyog thaum lub sijhawm lossis tom qab cov txheej txheem pleev xim, kom lawv dhau los ua lub teeb ua ntej cov xim thaum raug lub teeb, siv lub zog teeb los tiv thaiv cov xim molecules. Feem ntau muab faib ua cov khoom nqus ultraviolet thiab cov neeg sawv cev tiv thaiv ultraviolet, ua ke hu ua cov khoom txhim kho hnub.

Lub hnub ci ntsa iab ntawm cov ntaub dyed xim sib dua nrog cov dyes reactive

Qhov kev ploj ntawm cov xim reactive uas tshwm sim los ntawm lub teeb yog qhov kev tshuaj tiv thaiv photooxidative chlorination uas nyuaj heev. Tom qab nkag siab txog lub tshuab ntawm kev ploj ntawm lub teeb, peb tsim cov teeb meem rau qhov kev tshuaj tiv thaiv photooxidation hauv kev tsim cov qauv molecular ntawm cov xim kom ncua qhov kev ploj ntawm lub teeb. Piv txwv li, cov xim daj uas muaj Dole sulfonic acid pawg thiab pyrazolone, cov xim xiav uas muaj phthalocyanine methyl zan thiab diazo trichelding rings, thiab cov xim liab uas muaj cov hlau sib xyaw, tab sis tseem tsis muaj cov xim liab ci ntsa iab uas muaj zog tiv thaiv lub hnub.

Qhov kev tiv thaiv hnub ci ntawm cov ntaub dyed sib txawv nrog qhov kev hloov pauv ntawm qhov kev sib xyaw xim. Rau cov ntaub dyed nrog tib xim ntawm tib lub fiber, qhov kev tiv thaiv hnub ci nce nrog qhov kev nce ntawm qhov kev sib xyaw xim, thaum rau cov ntaub xim dawb, qhov kev tiv thaiv hnub ci txo qis sib xws thaum qhov kev sib xyaw xim qis. Txawm li cas los xij, qhov kev tiv thaiv hnub ci ntawm cov xim dyed feem ntau ntawm cov ntawv luam tawm xim dyed raug ntsuas ntawm qhov kev sib xyaw xim ntawm 1/1 ntawm qhov tob txheem (piv txwv li 1% owf lossis 20-30g / l xim dyed). Yog tias qhov kev sib xyaw xim yog 1/6, 1/12, lossis 1/25, qhov kev tiv thaiv hnub ci yuav txo qis heev.

Muaj ib txhia neeg tau tawm tswv yim siv cov tshuaj nqus ultraviolet los txhim kho lub hnub ci, tab sis qhov no tsis yog ib txoj kev zoo. Kev siv ultraviolet xav tau ntau yam thiab tsuas yog tuaj yeem txhim kho ib nrab xwb, thiab tus nqi yuav tsum tau txhim kho ntau heev. Yog li ntawd, tsuas yog xaiv cov xim pleev kom raug xwb thiaj li daws tau qhov teeb meem ntawm lub hnub ci.