化学性质
白色粉末,熔点为188℃。能溶于醇和热水中,并微溶于水,也能溶解于醚。
用途
该物质用于生产药物呋喃坦丁的中间体。
生产方法
以水合肼及尿素为原料,缩合成氨基脲液,再与丙酮反应得到成品。具体步骤如下:将水合肼(40%)与尿素混合后加热至97-104℃并回流6-7小时;降温至45℃后过滤,得到氨基脲液;将滤液冷却至25℃,加入丙酮,并自然升温至50-60℃保温1小时;最后冷至20℃以下,进行过滤、干燥,得到丙酮缩氨脲。重量配料比为:水合肼(40%):尿素:丙酮 = 1:0.67:0.56,收率可达90%。
作为中间体时,其外观为白色粉末,熔点在185-189℃之间。原料消耗定额为:水合肼(40%)300kg/t、尿素(工业品)870kg/t、丙酮(工业品)720kg/t。
类别
有毒物品
毒性分级
中毒
急性毒性
静脉注射-小鼠LD50: 90毫克/公斤
可燃性危险特性
可燃,加热分解时会释放有毒氮氧化物烟雾
储运特性
库房需通风、低温和干燥环境
灭火剂
干粉、泡沫、砂土、二氧化碳或使用雾状水
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | (2E,2'E)-2,2'-(1E,2E)-ethane-1,2-diylidenedihydrazinecarboxamide | 31909-46-3 | C4H8N6O2 | 172.15 |
In this paper, a theoretical model is proposed to investigate the centrifugal fans' transient behaviour in response to sudden imposed changes in pressure or flow rate. We are especially interested in the dissipative or creative energy transient behaviour of the fans located in actual aeraulic networks.
The model is based on the global modelisation of the motor and resistant torques (due to pressure and viscosity actions on the blades) which are present on the rotor and by their coupling with its inertia.
The model is then validated by experimental measurements which show its validity. In the case of the tested fan, the instantaneous characteristics (in particular the flow rate and rotation speed) have been correctly predicted by the model, with regard to time as well as amplitudes, provided the flow is not reversed.