(141122) -- VIENNA, Nov. 22, 2014 (Xinhua) --A security officer stands guard at Palais Coburg, the venue of nuclear talks in Vienna, Austria, on Nov. 22, 2014. The world's major powers and Iran are racing against time to reach a deal over Tehran's nuclear program. As for the Nov. 24 deadline, there are only two days left in the talks between Iran and the P5+1 group. (Xinhua/Zhang Fan)