以改性Y分子筛为催化剂,γ-丁内酯和乙醇胺为原料,采用γ - 丁内酯法两步合成N - 羟乙基吡咯烷酮 ( NHP ). N - hydroxyethylpyrrolidone ( NHP ) was synthesized from � � - butyrolactone and ethanolamine on Y molecular sieve catalyst by two steps.
The space telescope has taken the clearest pictures ever of Pluto.太空望远镜拍摄到了迄今为止最清晰的冥王星的照片。The space telescope has taken the clearest pictures ever of Pluto...太空望远镜拍摄到了迄今为止最清晰的冥王星的照片。Pluto seems to have suffered a major c...