Hardwood Thiab Softwood: Qhia Ib Tug Ntoo Ntoo lossis Ntoo Ntoo

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Hardwood Thiab Softwood: Qhia Ib Tug Ntoo Ntoo lossis Ntoo Ntoo
Hardwood Thiab Softwood: Qhia Ib Tug Ntoo Ntoo lossis Ntoo Ntoo

Video: Hardwood Thiab Softwood: Qhia Ib Tug Ntoo Ntoo lossis Ntoo Ntoo

Video: Hardwood Thiab Softwood: Qhia Ib Tug Ntoo Ntoo lossis Ntoo Ntoo
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neeg txhais li cas thaum lawv tham txog ntoo mos vs ntoo tawv? Dab tsi ua rau tsob ntoo tshwj xeeb yog softwood lossis hardwood? Nyeem rau kom paub qhov sib txawv ntawm cov ntoo mos thiab cov ntoo tawv tawv.

Hardwood thiab Softwood ntoo

Thawj qhov uas yuav tsum kawm txog ntoo tawv thiab ntoo mos yog cov ntoo ntoo tsis tas yuav tawv lossis mos. Tab sis "softwood vs. hardwood ntoo" tau dhau los ua ib yam khoom hauv 18th thiab 19th centuries thiab, thaum ntawd, nws tau hais txog qhov hnyav thiab hnyav ntawm cov ntoo.

Cov neeg ua liaj ua teb tshem lawv thaj av nyob rau sab hnub tuaj ntug dej hiav txwv thaum ntxov tau siv saws thiab axes thiab cov leeg thaum lawv nkag. Lawv pom ib co ntoo hnyav thiab nyuaj log. Cov no - feem ntau deciduous ntoo xws li ntoo qhib, hickory thiab maple - lawv hu ua "hardwood." Cov ntoo conifer nyob rau thaj tsam ntawd, zoo li cov ntoo ntoo dawb sab hnub tuaj thiab cov paj ntoo, tau teeb pom kev zoo piv rau "cov ntoo tawv," yog li cov ntoo no hu ua "softwood."

Softwood lossis Hardwood

Raws li nws muab tawm, txhua tsob ntoo deciduous tsis tawv thiab hnyav. Piv txwv li, aspen thiab liab alder yog lub teeb deciduous ntoo. Thiab tag nrho cov conifers tsis yog "mos" thiab lub teeb. Piv txwv li, longleaf, slash, shortleaf thiab loblolly ntoo thuv yog cov tuab tuab.

Lub sijhawm dhau mus, cov lus pib siv sib txawv thiab ntau yam kev tshawb fawb. Botanists pom tau hais tias thawj qhov sib txawv ntawm softwood thiab hardwood yog nyob rau hauv lub cell qauv. Ntawd yog, softwoods yog ntoo nrog ntoo uas muaj qhov ntev, nyias tubular hlwb uas nqa dej los ntawm qia ntawm tsob ntoo. Hardwoods, ntawm qhov tod tes, nqa dej los ntawm txoj kab uas hla loj dua los yog cov hlab ntsha. Qhov no ua rau cov ntoo tawv tawv, lossis "nyuaj" los pom thiab tshuab.

Qhov txawv ntawm Softwood thiab Hardwood

Tam sim no, kev lag luam ntoo tau tsim cov qauv hardness rau cov khoom sib txawv. Janka hardness test yog kab tias feem ntau siv. Qhov kev sim no ntsuas lub zog yuav tsum tau imbed ib lub pob steel rau hauv ntoo.

Kev siv hom kev ntsuas "hardness" no ua rau cov lus nug ntawm softwood vs. hardwood ntoo ib qho teeb meem ntawm qib. Koj tuaj yeem nrhiav Janka hardness rooj online teev cov ntoo los ntawm qhov nyuaj tshaj plaws (tsob ntoo hardwood hom) mus rau softest. Deciduous ntoo thiab conifers yog heev random sib xyaw nyob rau hauv daim ntawv.

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