Txhua yam kev hloov pauv hauv lub xeev ntawm cov teeb meem cuam tshuam nrog metamorphoses ntawm qhov kub thiab txias, siab. Ib yam khoom tuaj yeem sawv cev hauv cov xeev hauv qab no ntawm kev sib sau: khoom, kua, gaseous.
Nco ntsoov tias thaum hloov pauv mus, tsis muaj kev hloov pauv hauv cov ntsiab lus ntawm cov tshuaj. Kev hloov pauv ntawm cov khoom los ntawm cov kua mus rau lub xeev muaj zog tsuas yog nrog kev hloov pauv ntawm lub zog ntawm kev sib cuam tshuam ntawm cov tshuaj molecular, kev teeb tsa ntawm cov molecules. Kev hloov pauv ntawm ib lub xeev mus rau lwm qhov yog hu ua kev hloov pauv theem.
Muaj
txheej txheem no suav nrog kev hloov pauv ntawm cov khoom ua kua. Rau nws qhov kev siv, xav tau qhov kub thiab txias.
Piv txwv li, ib tus tuaj yeem soj ntsuam qhov xwm txheej zoo li no. Physics yooj yim piav qhia txog cov txheej txheem ntawm melting snowflakes nyob rau hauv qhov kev txiav txim ntawm lub caij nplooj ntoos hlav rays. Cov dej khov me me uas yog ib feem ntawm cov daus, tom qab cua sov rau xoom, pib tawg. Melting tshwm sim maj mam. Ua ntej, cov dej khov absorbs tshav kub zog. Raws li qhov kub thiab txias hloov, qhov ua tiav ntawm cov dej khov rau hauv cov kua dej tshwm sim.
Nws yog nrog los ntawm kev nce ntxiv hauv qhov nrawm ntawm cov khoom, thermal zog, nce ntxivInternal zog.
Tom qab mus txog qhov ntsuas, hu ua lub ntsiab lus melting, muaj qhov tawg ntawm cov qauv ntawm cov khoom. Molecules muaj kev ywj pheej ntau dua, lawv "dhia", tuav ntau txoj haujlwm. Cov khoom molten muaj lub zog ntau dua li lub xeev ruaj khov.
Kho kub
Kev hloov pauv ntawm cov tshuaj los ntawm lub xeev ua kua mus rau lub xeev muaj zog yog ua tiav ntawm tus nqi kub. Yog tias cua sov tawm ntawm lub cev, ces nws khov (crystalizes).
Kho qhov kub thiab txias yog suav tias yog ib qho ntawm cov yam ntxwv tseem ceeb tshaj plaws.
Crystalization
Kev hloov ntawm cov khoom los ntawm lub xeev ua kua mus rau lub xeev cov khoom yog hu ua crystallization. Thaum hloov cov cua sov mus rau cov kua nres, qhov kub thiab txias poob mus rau ib qho nqi. Cov theem hloov ntawm ib yam khoom los ntawm cov kua mus rau ib tug khoom lub xeev nyob rau hauv physics yog hu ua crystallization. Thaum xav txog ib yam khoom uas tsis muaj impurities, lub melting point sib haum mus rau crystallization index.
Ob txoj kev ua haujlwm maj mam. Cov txheej txheem crystallization yog nrog los ntawm kev txo qis hauv nruab nrab kinetic zog ntawm cov molecules uas muaj nyob rau hauv cov kua. Lub zog ntawm attraction, vim hais tias cov hais yog tuav nyob rau hauv ib tug nruj kev txiav txim, inherent nyob rau hauv solids, nce. Tom qab cov khoom tau txais kev txiav txim, ib lub siv lead ua yuav tsim.
Lub xeev ntawm kev sib sau ua ke yog lub cev ntawm cov khoom, nthuav tawm hauv ib qhothaj tsam ntawm qhov kub thiab txias. Nws yog tus yam ntxwv los ntawm ntau yam khoom uas tau hloov pauv hauv cov sijhawm xaiv:
- lub peev xwm ntawm cov khoom hloov pauv thiab ntim;
- tsis muaj (muaj) ntawm qhov ntev lossis luv-nqi.
Cov txheej txheem crystallization yog txuam nrog entropy, dawb zog, ntom, thiab lwm yam khoom siv lub cev.
Ntxiv rau cov kua, cov khoom khib nyiab, cov ntawv gaseous, lwm lub xeev ntawm kev sib sau yog tso tawm - ntshav ntshav. Gases tuaj yeem dhau mus rau hauv qhov xwm txheej ntawm qhov kub thiab txias ntawm qhov siab tas li.
Txoj kev txwv ntawm ntau lub xeev ntawm cov teeb meem tsis yog ib txwm nruj. Physics tau lees paub qhov muaj nyob ntawm amorphous lub cev muaj peev xwm tswj xyuas cov qauv ntawm cov kua nrog me ntsis fluidity. Cov kua dej muaj peev xwm ua kom polarize cov hluav taws xob hluav taws xob uas dhau los ntawm lawv.
Zoo kawg
txhawm rau piav qhia ntau lub xeev hauv physics, lub ntsiab lus ntawm lub thev naus laus zis yog siv. Cov xwm txheej tseem ceeb yog cov xeev uas piav txog kev hloov pauv ntawm ib theem mus rau lwm qhov. Lub cev muaj zog yog qhov txawv los ntawm kev khaws cia ntawm lawv qhov chaw nruab nrab ntawm lub sijhawm ntev. Lawv yuav ua rau me ntsis oscillations (nrog rau qhov tsawg kawg nkaus amplitude) nyob ib ncig ntawm txoj hauj lwm sib npaug. Crystals muaj ib yam zoo li, uas yuav hloov thaum nws mus rau hauv lub xeev ua kua. Cov ntaub ntawv hais txog qhov kub thiab txias (melting) tso cai rau cov kws kho mob siv cov kev hloov pauv ntawm ib lub xeev ntawm kev sib sau mus rau lwm qhov. Cov hom phiaj siv tau.
