小母牛在牛栏里吼叫。A heifer bellowed in her stall.怀小牛的小母牛最适合这项工作.In - calf heifers are admirable for this work.他用12头山羊换了我的1头小母牛.He swapped me a dozen goats for one of my female calf....
在催化剂存在下,用双氧水氧化乙二醛溶液快速合成了乙醛酸.Glyoxylic acid was rapidly synthesized by catalytic oxidation of glyoxal with H 2 O 2.利用报废的液体推进剂硝酸-27S和乙醛制备乙二醛.Glyoxal is prepared with waste liquid propellant HNO 3 - 27 S and ethanal.乙二醛 、 乙...