The first five 9,000-tonne pneumatic grain storage facilities in China were successfully inflated into shape on Monday in Changsha, capital of central China's Hunan Province, marking another step forward in the country's efforts to develop its fourth-generation grain storage technology.
Each of the five silos, with a diameter of 24 meters and a height of 33 meters, can store up to 9,000 tonnes of grain, enough to supply food for 23 million people for one day.
"What's unique about these pneumatic silos is that they can withstand rain and cold air compared to traditional grain storage facilities. For the sake of storing grains, their airtightness is six times higher than national standards, and their thermal insulation performance is three times better than conventional squat silos," said Wang Yue, head of the engineering design center at the Chengdu Grain Storage Research Institute under Sinograin.
Beyond the outer air membrane, the silos feature a reinforced concrete layer for structural support and a polyurethane thermal insulation layer. Once operational, a network of sensors inside will allow for real-time, comprehensive monitoring of the grain's temperature. The nearly oxygen-free environment also helps control pests, ensuring optimal grain quality.
In addition to their waterproofing, insulation, and airtightness, the silos offer a significant reduction in operational and maintenance costs, which are expected to be 30 percent lower than those of traditional silos.
"The silos' insulation and concrete structure are built inside the air membrane, unaffected by adverse weather conditions like rain, snow, or wind. What once required a team of over 100 workers can now be completed by just 18 people, with the construction period reduced by a quarter compared to the previous generation of squat silos," said Jin Feng, head of the pneumatic silos project at the China Coal No. 68 Engineering Co., Ltd.
The five 9,000-tonne silos are expected to be completed by the end of this year and enter operation in February next year.
China takes another step forward in developing next-generation granary
China takes another step forward in developing next-generation granary
The Exhibition Hall of Evidence of Crimes Committed by Unit 731 of the Japanese Imperial Army in northeast China's Harbin released on Thursday a 38-minute video of a former member of Unit 731, a notorious Japanese germ-warfare unit during World War II (WWII).
In the footage, former Unit 731 member Tsuruo Nishijima detailed how the unit used meteorological data to carry out bacterial dispersal and frostbite experiments.
The video was recorded in 1997 by Japanese scholar Fuyuko Nishisato and donated to the exhibition hall in 2019, according to the hall, which was built on the former site of the headquarters of Unit 731 in Harbin, capital city of Heilongjiang Province.
Nishijima joined Unit 731 in October 1938 and served in the unit's meteorological squad. The squad was not a simple observation section but rather an auxiliary force supporting the unit's human experiments in the field by measuring wind direction, wind speed and other conditions to ensure optimal experimental results.
Nishijima confirmed in the footage that "the meteorological squad had to be present at every field experiment." He testified to the "rainfall experiments" conducted by Unit 731, which involved aircraft releasing bacterial agents at extremely low altitudes.
At a field-testing site in Anda City, Heilongjiang, Unit 731 aircraft descended to about 50 meters above the ground and sprayed bacterial culture liquids onto "maruta" -- human test subjects -- who were tied to wooden stakes. Each experiment involved about 30 people, spaced roughly 5 meters apart. After the experiments, the victims were loaded into sealed trucks and transported back to the unit, where their symptoms and disease progression were recorded over a period of several days.
Nishijima also revealed that a Japanese military doctor once died after removing the mask and becoming infected during an experiment, indirectly proving the extreme virulence of the bacterial agents.
The video further disclosed details of the meteorological squad's involvement in frostbite experiments. To study wartime needs in frigid regions, the invading Japanese army forced the victims to expose their bodies for five to ten minutes in temperatures ranging from minus 20 to minus 35 degrees Celsius and observed their physical reactions.
"For example, during frostbite experiments, we would be sent outside to observe the weather. They wouldn't bring many people out at once, only two or three, who would be forced to take off their upper garments or all their clothes. In fact, it was already quite tough to stay out there for five to ten minutes, because it was too cold," Nishijima said.
According to the exhibition hall, Unit 731 had a separate frostbite laboratory, with Hisato Yoshimura serving as the leader of the unit's frostbite study squad from 1938 to 1945.
In a paper on frostbite published in 1941, Yoshimura recorded data from live human experiments to study the occurrence of frostbite and pathological changes in the human body under different conditions.
"This is a form from the paper. Titled 'The Severity and Process of Frostbite,' it divides frostbite into three stages. The symptoms of the first-degree frostbite are redness and swelling. Blisters appear in the second stage. And the third-degree frostbite features necrosis and ulceration. It says here that, in the third stage, from the 50th to the 60th day, toes and fingers detached. There is no doubt that these data were obtained through numerous human experiments," said Tan Tian, a researcher of the exhibition hall.
Nishijima's video, a piece of oral history from a perpetrator's perspective, further reconstructs the criminal chain of Unit 731 and once again demonstrates that the invading Japanese army's biological warfare crime was systematic and inhumane, and was an undeniable historical truth, according to the exhibition hall.
"Unit 731's frostbite experiments were essentially conducted to prevent and treat frostbite during combat in cold environments. However, for the so-called prevention and treatment of frostbite, they caused frostbite on living people for experiments and data analysis. So in nature, it still serves the purpose of war," said Jin Shicheng, director of the Department of Publicity, Education and Exhibition at the hall.
Unit 731 was a top-secret biological and chemical warfare research base established in Harbin as the nerve center for Japanese biological warfare in China and Southeast Asia during WWII.
At least 3,000 people were used for human experiments by Unit 731, and more than 300,000 people in China were killed by Japan's biological weapons.
Video offers new evidence of Japan's wartime germ-warfare crimes in northeast China
