Jan-Christer Janson (front left), professor of technical biochemistry at Uppsala University of Sweden, and Okimura Kazuki, head of the Japan Science and Technology Agency, together with other scientists, receive the 2015 state science and technology awards at a ceremony in the Great Hall of the People in Beijing on Friday. President Xi Jinping and Premier Li Keqiang also attended. ZHOU WEIHAI/CHINA DAILY

The 2015 state science and technology awards honoring the contributions of 295 research projects and seven foreign experts were bestowed at a ceremony in the Great Hall of the People in Beijing on Friday, but the highest award remained vacant.

The state science and technology awards comprise five award categories, of which the Preeminent Science and Technology Award is the highest.

The top prize has previously been awarded to 25 scientists, including China's "father of hybrid rice" Yuan Longping, since it was established in 2000. There were one or two winners each year except 2004, the first time there was no recipient.

"We can only express regret over the vacancy this year," an unidentified official from the National Office for Science and Technology Awards, which is in charge of collecting nominations and organizing the voting, was quoted by People's Daily as saying.

The official said that the country's first Nobel laureate in medicine, Tu Youyou, who won the 2015 Nobel Prize for Medicine in October, was not nominated for this year's prize. The nominations, submitted by more than 130 government agencies, research institutes and individual scientists, were made from early November to mid-December 2014.

In other award categories, this year saw a trend in which the average age of principal winners of the State Natural Sciences Award was just 47.6.

Pan Jianwei, 45, a quantum scientist at the University of Science and Technology of China, won the top prize in the State Natural Sciences Award category.

The quantum communications equipment developed by Pan's team was applied to ensure communication security in the 18th Party Congress in 2012 and at the parade in September to mark the 70th anniversary of victory in the War of Resistance against Japanese Aggression (1937-45).

Some large-scale scientific projects, such as the Beijing-Shanghai High-Speed Railway, have won awards as well. But experts said it becomes increasingly difficult to give the credit to some individuals, since China is initiating more mega-projects.

Jiang Fengyi, top winner of the State Technology Invention Award, said: "More than 60 researchers had contributed to the program. But according to the restricted number, we can only have six apply for the award."

Chen Yanjing, a professor of geology at Peking University who won the National Award for Technological Invention, said "the prize should recognize innovative ideas instead of researchers' specific work".