Liu Jieyi(front), China's permanent representative to the UN, votes in favor of a Security Council resolution at the UN headquarters in New York on Sept. 23, 2016. The UN Security Council on Friday adopted a resolution to call on all states to refrain from conducting any nuclear weapon test explosion, meanwhile commemorating the 20th anniversary of the signing of the Comprehensive Test Ban Treaty (CTBT). (Xinhua/Wang Ying)