Training a dog requires the expenditure of time and effort. 訓練一條狗需化時(shí)間和精力。
This technology is very useful for decreasing the time of hydrogenation catalyst presulfurization and the equipment eroding as well as pollution. 該工藝對縮短加氫催化劑的預硫化時(shí)間,減少調備腐蝕和環(huán)境污染,具有非常積極的意義。