PetroChina's flag flutters next to the Chinese national flag at a gas station in Beijing in this August 29, 2013 file photo. To match Special Report CHINA-PURGE/CNPC REUTERS/Kim Kyung Hoon/Files ... more 
PetroChina's flag flutters next to the Chinese national flag at a gas station in Beijing in this August 29, 2013 file photo. To match Special Report CHINA-PURGE/CNPC REUTERS/Kim Kyung Hoon/Files (CHINA - Tags: BUSINESS ENERGY) less 
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Reuters | Photo By KIM KYUNG-HOON / REUTERS
Thu, Jul 24, 2014 4:19 PM EDT