非 is a single word,並不is a phrase ,both of them can mean"no,not like this "And you can also use 並非,they're all same .So 並不can substitute 並非.example:我並不/並非討厭妳。I don't hate you. But we don't say 我非討厭妳. when 非make phrases with other words it can have many different meanings.example:非常 very 非但...而且...not only...but also... ect.

非 can have many different meanings in different contexts. It means wrong in 是非(right and wrong), i'll give you some examples, 孰是孰非，是非难辨. It can also mean to blame,比如：非难；无可厚非. And in this sentence: 我非去不可。非 means must. And also 非 means 不是(be not), so 并不(是) is the same thing as 并非,but 并非 sounds more formal to a native ear. For example, 这并不是/并非最明智的做法。 But 并 doesn't necessarily have to go with 非，you can see that in 非此即彼（literally 不是这个就是那个, or in english: either this or that), 非 alone means 不是 And in 非洲，南非，东非，非 means Africa :) Hope this will help you understand the word more thoroughly.

非used as antony，it means not, e.g. 洗衣机在正常使用情况下不会出现问题，非正常情况下则不好说。 But it is according to our custom , you can nerver learn it from example. Bucause we treat 非正常 as a word, but not all 非+word = new word.

tried to help you out,yet lost all that i've typed when switching to another app since i'm using my phone, frustrated will try again tomorrow morning on my computer, and you can add me on Skype so that i can explain it to you more clearly. Skype ID:hitting_asteroid