no是形容词,在句中作定语,表示否定,意思是没有或不是,可以修饰可数名词的单复数和不可数名词,相当于not a或not any,比如说：
see no reason,等于not see a reason,看不出任何理由.
There is no such disease. 等于There isn't such a disease,没有这样的疾病.
not是副词,通常位于be动词、情态动词、助动词之后,构成否定形式,意思是“不”,“没有”,它也可以位于动名词、不定式、分词（包括现在分词、过去分词）之前,构成否定形式,意思同样是“不”,“没有”.在省略结构里,not可以放在包括名词、动词、形容词、副词等的一切词类前面,表示否定,比如：
Tim isn't a young man.
He asked me not to be late.
Let's not go.
It seems not to be right.
Not having a vocabulary book is a serious problem.
Not having had anything for a whole day, he wolfed down three bowls of rice.
I need to have some meat because it has some minerals and vitamins not found in vegetables.
No, not tomorrow.
希望我能帮助你解疑释惑.