It depends on the content. If you write articles about women & men relationship and sex psychology, then there should be no problems.
Google hate the word "SEX". I think you can't run adsense in such type of sites. go for some other advertisers lik Adbrite and bidvertiser etc.
Nope it is not acceptable by google adsense, adult material is against google TOS. It will only get your account banned.
But what exactly is the difference between 'mature' and 'adult'? Also, what does getting banned mean? Is your bank account banned from using adsense even on other sites, or is it just that one offending site that is banned?
if your website is for Educational perpose not Adult Picture and Videos.. I think it Approved by Google if it has Lot of traffic...