World's largest superconducting magnet for fusion reactor unveiled in China

The world's largest Toroidal Field (TF) superconducting magnet for fusion reactors passed technical acceptance by an expert panel on Saturday in Hefei, capital city of east China's Anhui Province.

The volume of this magnet, weighing 582 metric tons, is 1.3 times that of the TF magnet used in the International Thermonuclear Experimental Reactor, and its energy storage capacity is three times greater, according to its developers at the Hefei-based Institute of Plasma Physics, Chinese Academy of Sciences.

The magnet, one of the most crucial components of a fusion reactor, is responsible for creating the toroidal magnetic field, which firmly constrains the plasma and reduces the impact and energy loss of high-energy particles on the vacuum chamber walls.

In the future, 16 such magnets will be combined and built together to form a complete Toroidal Field.

"Its function is to confine the plasma, preventing it from hitting the walls within the vacuum chamber. The intensity of its magnetic field is related to the temperature and density required for the plasma in the future. A ring composed of 16 coils will generate a magnetic field of 6.5 teslas," said Wu Yu, a researcher at Chinese Academy of Sciences' Institute of Plasma Physics (ASIPP).

The institute has been developing the magnet for six years.

"This coil is the heaviest in the world, with the highest energy storage capacity among all superconducting coils currently. The special stainless steel we are currently using, as well as our insulating materials and superconducting materials, are all domestically produced. This project is realized with 100 percent of domestic products," said Song Yuntao, head of the ASIPP.

It is one of the two key superconducting magnets related to fusion reactors that were announced by China on the day. The other magnet, the high-temperature superconducting central solenoid coil, completed full-condition parameter testing on the same day.

World's largest superconducting magnet for fusion reactor unveiled in China

World's largest superconducting magnet for fusion reactor unveiled in China

A veteran firefighter in Cali, the capital of Colombia's hard-hit Valle del Cauca province, participated in a harrowing rescue operation that followed the deadly earthquake on Monday and depicted the painstaking efforts to pull a mother and her son from the rubble of a collapsed building.

Nestor Giraldo, an emergency coordinator with the Cali volunteer fire brigade with 27 years of experience, rushed to the Tecundama district in southern Cali after the quake.

At the site of a collapsed five story building, his team located a mother and her son on what had been the third floor. Rescuers managed to pull the son out first. He was conscious, though injured in the head and legs, and was taken to a nearby hospital for further treatment.

However, the rescue became more complicated as they ventured deeper into the collapsed building to reach the mother.

"She was trapped about three meters deeper, but it felt like she was a world away. We had to chip through each floor, one by one, inch by inch, because the whole structure could come down on us at any time," said the firefighter.

The team had been on site since around 8:00, yet by 17:00, they were still working to get close enough to rescue her.

"Part of the building was pressing down on her legs and abdomen. The rescue was incredibly difficult, because she was in agony, trapped, and badly hurt. The gap for medics to crawl in and apply a tourniquet was so narrow that we couldn't make it any bigger. We couldn't get to her from above. We could only work from below," said Giraldo.

The mother was eventually rescued with the help of more than 40 rescuers from the fire department, The Red Cross, and other groups, as well as community members.

Giraldo said he would press on as he always has: to rescue the living, to recover the lost, and to offer whatever solace he can to the families left behind.

Colombian firefighter recalls urgent rescue of mother and son from collapsed building after quake