这种物质很容易由甲醛和肼反应而得到.The material is readily prepared by reaction of formaldehyde and hydrazine.甲醛能慢慢使多种病毒失去活性.Formaldehyde slowly inactivates many viruses.二氧化硫和甲醛都可产生刺激.Sulfur dioxide and formaldehyde both produce irritati...
Consultants in heliport development and helicopter operations. Specializes in planning, design and development of and helipads.为直升机机场及其营运提供顾问服务, 擅长直升机机场的规划 、 设计与开发....