断续的小雨下了有好几天了.The rain has been on and off for several days.未焊满未焊满是指焊缝表面上连续的或断续的沟槽.D, do not weld fully weld fully to denote weld superficially continuous or intermittent groove....
介绍了利用BTC生产 过程中产生的副产品氯化氢气体合成盐酸乙脒的工艺研究.This paper introduces the production technology of acetamidine hydrochloride and hydrogen chloride produced in BTC synthesis.采用重量分析法测定盐酸乙脒中难挥发杂质的含量.The content of in volatile impuriti...