(EnergyAsia, January 8 2010, Friday) — Brazil’s Petrobras has signed a memorandum of understanding with Petrochina to explore the feasibility of exporting ethanol to China. PetroChina, the country’s largest oil producer, signed the agreement with Petrobras Biocombustivel, a subsidiary of the Brazilian energy giant. The companies did not disclose details of the deal. Energy-short China…