N - hydroxyethylpyrrolidone ( NHP ) was synthesized from � � - butyrolactone and ethanolamine on Y molecular sieve catalyst by two steps.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 ).Surface active propertie...
The caterpillar will eventually metamorphose into a butterfly.毛毛虫最终将蜕变成一只蝴蝶。the metamorphosis of a caterpillar into a butterfly从毛毛虫到蝴蝶的蜕变A butterfly is produced by metamorphosis from a caterpillar.蝴蝶是由毛虫脱胎变成的....