离别的时刻the moment of parting歌曲最后道出了离别的哀怨.The last note of the song rang out plaintively.我的朋友在离别前给我一张照片留作纪念.My friend gave me his picture as a keepsake before going away....
Calcium carbonate occurs in the allomorphs calcite and aragonite.同质异晶的方解石和文石中含有碳酸钙.And some calcite - secreting organisms also add magnesium to the mix.有些分泌方解石的生物,会在分泌物中加入镁.The chemical composition of the melo shell is c...
Some stratification exists in the spray produced by any liquid propellant injector.由任何液体推进剂喷注器所产生的喷雾都存在某些成层现象.The small lower hole is that for the injector.下方小洞用于装喷嘴.Chamber compatibility and injector durability involve ...