06
Oct
Oct
Txog Cov Khoom Siv Hauv Chav Ua Noj: Cov Khoom Benjamin Thompson tau sau tseg thaum pib ntawm lub xyoo pua puv 19 tias cov tais diav hauv chav ua noj feem ntau yog ua los ntawm tooj liab, nrog rau ntau yam kev siv zog los tiv thaiv tooj liab los ntawm kev cuam tshuam nrog zaub mov (tshwj xeeb yog nws cov kua qaub) ntawm qhov kub tau siv rau ua noj, nrog rau tinning, enamelling, thiab varnishing. Nws pom tias hlau tau siv los ua […]