SHANGHAI, July 11 -- "Xuelong" (Snow Dragon), China's research vessel, left a Shanghai port on Monday for the Arctic, the country's seventh expedition to the polar region.

Xia Limin, from the State Oceanic Administration, said that scientists will undertake research on marine chemistry, ecology, geology, geophysics and sea ice dynamics.

Xia, who is also research team leader, said that American and French scientists had been invited to join the 128-member research team on a 10,000-sea-mile journey that is expected to take 78 days.

American and French scientists will join China's Arctic expedition team in ocean and environment research, a move Xia said that will help "promote peace, stability and sustainable development in the Arctic region."

In addition to areas covered by Xuelong's previous Arctic expeditions, the ship will also visit the Mendeleyev Ridge in the Arctic Ocean.

The ship is equipped with two helicopters, research support systems and emergency equipment, he said.