Is there anyway to know why they were not approved?
You could contact mx (the lead content admin) and ask him..but i'm unsure as to whether or not he would be able to single out your unapproved uploads from the thousands of others to provide an answer..
I don't know what the subject matter was in these pics that you took yourself..but if they got denied the only advice i can give for future uploads is not to take pics of that..lolz
I know this doesn't help much..but i've not got a lot to work with other than you saying some pics got rejected..