iav, hlau, yas, thiab varnished ntooyog cov piv txwv ntawm cov ntaub ntawv tsis ntxeem tau, thaum tsis kho ntoo, drapes, ntaub pua plag, thiab cardboard yog ntxeem tau.
piv txwv ntawm cov ntaub ntawv tsis ntxeem tau yog dab tsi?
Piv txwv ntawm qhov tsis muaj qhov ntxeem tau suav nrog iav, yas, hlau, thiab ntoo varnished. Latent prints rau ntawm qhov chaw tsis muaj qhov ntxeem tau zoo li tsis yooj yim, yog li lawv yuav tsum tau khaws cia sai li sai tau.
5 piv txwv ntawm cov khoom ntxeem tau dab tsi?
Ntawv, duab los qhia, daim txhuam cev, pob zeb pumice, ntoo tsis kho, thiab cork yog ob peb yam piv txwv ntawm cov khoom ntxeem tau. Cov khoom tsis muaj dej tsis zoo xws li cov hlau tsis muaj steel, tawv npog, thiab cov khoom siv hluavtaws tawv lossis lwm yam khoom siv feem ntau.
piv txwv ntawm porous yog dab tsi?
A daim txhuam cev yog ib qho piv txwv ntawm cov khoom ntxeem tau vim nws muaj ntau qhov chaw khoob piv rau nws qhov ntim. … Daim txhuam cev, ntoo, roj hmab, thiab tej pob zeb yog cov khoom ntxeem tau. Hauv qhov sib piv, marble, iav, thiab qee cov yas tsis ntxeem tau thiab muaj ob peb lub hnab qhib cua (los yog qhov hws).
Cov paj rwb puas yog pob?
No, paj npaim yog ntxeem tau.
