【多选题】应用固体分散技术制备固体分散体应注意
A.
常用的载体材料有水溶性、难溶性和肠溶性载体材料
C.
液体药物在固体分散体中所占比例不宜超过10%.
D.
一般药物与载体材料的重量比通常在1:5~1:20
【简答题】按分散状态分类,固体分散体可分为 、 、 三种类型。 固体分散体的载体材料有水溶性、水不溶性和 。
【单选题】在室温下,下列物质分别与硝酸银的氨溶液作用能立即产生沉淀的是()。
【简答题】固体分散体常用的载体材料主要有()、难溶性载体材料和肠溶性载体材料三类。
【单选题】Wiladee used to work as an officemanager, earning $25,000 per year. She gave up that job to start a tailoringbusiness. In calculating the economic profit of her tailoring business, the$25,000 income t...
【单选题】The economic profit of a perfectly competitive firm
A.
is less than its total revenue.
B.
equals its total revenue.
C.
is greater than its total revenue.
D.
is less than its total revenue if its supply curve is inelastic and is greater than its total revenue if its supply curve is elastic.
【判断题】The economic profit will be less than accounting profit because it takes into account an extra cost.
【判断题】当团体规模不断扩大,队员的动机逐渐下降,就会产生社会性懈怠,从而降低活动效率。
【单选题】Suppose firms in a perfectly competitive market are earning an economic profit. As new firms enter, the price ________ and the economic profit of each existing firm ________.