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  • What is the role of China's breakthrough in ultra-low temperature refrigeration technology, which is 0.01 degrees different from absolute zero?

    What is the role of China's breakthrough in ultra-low temperature refrigeration technology, which is 0.01 degrees different from absolute zero? 馬上咨詢

            The lowest temperature in the earth's south pole is - 54 degrees below zero. It is difficult for ordinary creatures to survive here. Pluto's surface temperature is 200 degrees below zero, and the planet's air is completely frozen.

      boomerang nebula

          The bumogen nebula, 5000 light-years from earth, is the coldest known place in outer space with a temperature as low as minus 272 degrees. But this is still not the lowest temperature the universe can reach.

          The coldest place in the universe was at Sandia National Laboratory in the United States. Physicists made the temperature reach minus 272.59 degrees, which was once the lowest temperature in the known universe.

          So how is this ultra-low temperature obtained?

          Scientists have given the answer from the micro world. Everything in the universe is composed of particles. They are moving irregularly all the time. The faster the speed, the higher the temperature of the object.

          When a particle of an object comes to a complete standstill, its temperature will drop to a limit value. That's minus 273.15 degrees Celsius.

      But absolute zero is impossible.

          Modern practical refrigeration technology can generally be divided into three categories. The first category is based on aerodynamics to continuously extract heat from the low temperature end, such as freezing and storing food with a refrigerator or cooling with an air conditioner. These refrigeration needs to be realized by a compressor.

          The second is the use of some chemical and physical phenomena, such as thermoelectric effect, paramagnetic effect and tunneling effect. For example, a water dispenser adopts electronic refrigeration, and the basic principle is the thermoelectric effect of temperature difference.

      The last one is to use cryogenics directly, such as throwing ice cubes into beer.

      Liquid nitrogen refrigerant technology

          Generally, different refrigeration methods are adopted according to needs. Since the air liquefaction technology and Dewar technology are mature, nitrogen liquefaction as refrigerant has become a very convenient and practical refrigeration technology.

          In addition, nitrogen is the main component in the air, and the current cost of liquid nitrogen is cheaper than mineral water. Moreover, nitrogen is chemically inert and can be in direct contact with biological tissues. Even if it is frozen immediately, it will not destroy biological activity.

          On the science and technology open day of the Institute of physics of the Chinese Academy of Sciences, there was a small online Red science experiment. The living goldfish was frozen into ice pimples in liquid nitrogen, and then thawed in normal temperature water. The small fish immediately regained its vitality.

          Therefore, liquid nitrogen has a wide range of uses. It can quickly freeze food, such as Malaysian durian imported from China, preserve living tissues, such as biological samples and the storage of sperm and eggs, and even treat some skin diseases. Its principle is to use low temperature to quickly kill cells in the disease area.

      Liquid nitrogen technology is used for human body freezing.

          James Bedford was the richest man in the United States in the middle of last century, but unfortunately he suffered from cancer. He believes that cancer can be cured in the future.

          At that time, an electrician named Robert atinger was studying liquid nitrogen refrigeration technology, which brought hope to Bedford.

          He sponsored $100000 for the electrician, signed an agreement with atinger to freeze himself, and agreed to thaw in 50 years and revive himself by using modern science and technology.

          In 1967, Bedford died of cancer. Atinger frozen him as promised, but 54 years later, Bedford is still frozen in an iron box.

          Today's science and technology can't bring people back from the dead. Cancer is still a disease perplexing human beings, and liquid nitrogen is only minus 196 degrees. Cell molecules will still move slowly at this temperature.

          Movement means that life is passing with time. Unless the temperature is reduced to absolute zero, there is a chance to completely freeze life, or even freeze time.

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