常見例句According to the characteristics of pinnoite in Dachaidan, a new technology of preparing boric acid with two-step sulfuric acid method was studied.摘要針對大柴旦柱硼鎂石鑛特點，對酸法制硼酸進(jìn)行了工藝優(yōu)化研究。 返回 pinnoite