Cov neeg feem ntau ntsib emulsions nyob rau hauv lub neej txhua hnub, qee zaum tsis tas xav tias nws yog lawv. Cov tshuaj no yog dab tsi, lawv yog dab tsi?
Ib qho emulsion yog ib homogeneous dispersion system ntawm ob lub kua tsis ua kua. Outwardly, nws yog xyaum tsis txawv ntawm tsuas yog homogeneous kua. Qhov sib txawv ntawm emulsion thiab tom kawg muaj nyob rau ntawm cov me me mob ntawm cov dispersion theem, muab faib rau hauv cov kua tseem ceeb, i.e. nruab nrab dispersion. Qhov piv txwv yooj yim tshaj plaws ntawm cov kab ke, uas txhua tus tau ntsib hauv lub neej txhua hnub, yog mis nyuj. Hauv nws, mis muaj roj yog qhov dej tawg hauv dej.
Hom ntawm emulsions
Lub hauv paus tseem ceeb cuam tshuam rau qhov piv ntawm cov emulsion mus rau ib hom tshwj xeeb:
- muaj pes tsawg leeg ua kua theem
- kev sib piv ntawm cov kua theem
- Txoj kev emulsification
- qhov xwm ntawm emulsifier
- lwm yam
Raws li cov ntsiab lus no, hom emulsions hauv qab no yog qhov txawv:
Ncaj. Lawv tsim los ntawm cov kua dej tsis ncau kua dej tawm hauv qhov nruab nrab polar, feem ntau cov roj-hauv dej. Cov emulsifiers zoo tshaj plaws rau emulsions ncaj qha yog poov tshuaj thiab sodium ntsev ntawm fatty acids, i.e. cov xab npum, uas, ua adsorbed nyob rau sab hauv cov tee, txo qhov nro ntawm qhov chaw, ua kom lub zog muaj zog, thiab tiv thaiv kev rhuav tshem.
Rov qab (invert) emulsions. Cov emulsions no suav nrog kev siv dej-hauv-roj. Emulsifiers - insoluble ntsev ntawm fatty acids, piv txwv li, calcium, aluminium, magnesium.
Lyophilic. Cov emulsions no muaj peev xwm tsim tau qhov kev tshwm sim, vim tias lawv muaj cov thermodynamically ruaj khov. Tsim nyob ze rau qhov tseem ceeb sib xyaw ua ke kub ntawm ob ntu. Ib qho piv txwv ntawm xws li emulsion yog txiav kua dej.
Lyophobic. Cov emulsions no tsis ua rau lawv tus kheej, txij li lawv tsis muaj lub zog ruaj khov rau thermodynamic. Kev siv tshuab los cuam tshuam lossis cov txheej txheem ntawm kev tsim cov tee ntawm ib ntawm theem ntawm kev daws teeb meem yog txoj hauv kev tseem ceeb rau kev tsim cov lyophobic emulsions.
Cov hau kev rau kev tsim emulsions
Muaj ob txoj hauv kev kom tau txais emulsions: droplet crushing, zaj duab xis tsim thiab tawg.
Pob zeb poob. Cov theem dispersion tau maj mam ntxiv rau qhov nruab nrab dispersion nyob ib puag ncig ntawm emulsifier nrog nplawm. Raws li qhov tshwm sim, muaj ntau yam tee dej me me tau tsim los. Tus naj npawb ntawm cov tee thiab lawv qhov loj me yog nyob ntawm qhov xwm ntawm emulsifier, nplawm ceev, qhov kub, pH ntawm qhov nruab nrab, thiab tus nqi ntawm kev qhia ntawm qhov dispersion theem.
Kev tsim zaj duab xis thiab tawg. Ib qho kua uas tsis sib xyaw nrog qhov nruab nrab dispersion tsim ib zaj duab xis rau nws saum npoo, uas tau tawg los ntawm cua npuas tuaj tawm ntawm lub raj tshwj xeeb hauv qab ntawm lub nkoj. Hauv qhov no, sib tov sib xyaw thiab emulsification tshwm sim. Ib qho kev ua haujlwm zoo sib xws ntawm kev ua, tab sis zoo dua, yog kev siv ultrasound los tsim thiab do em emulsion.
