AJI is Ameristar Jet Charter, Inc
Are these cargo flights?
I used this website to do a search for AJI : http://www.house747.freeserve.co.uk/
It came up with the airline name and did a search in the 737-100/-200 Census at: http://www.bird.ch/bharms/asr_sh00.htm
You see its simple.
What a great resource the internet is !!