Hundred-YearEconomist⁵³⁵⁸¹⁺¹ 例句 Acetylene is a one hundred-year- old metal cutting gas, acetylene process of high quantity of heat, high stability has been considered the most ideal gas cutting. 乙炔是已有百年历史的金属气割燃气工艺,乙炔的高热量、高稳定性一直被认为是最理想的切割燃气。 pmqgj.net