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On October 14, 2018, a Chinese company broke through the ultra-low temperature refrigeration technology, which is only 0.01 degrees away from absolute zero, and this new technology is of great significance for future research and development.
Today, Xiaobian will take you to uncover the secret of this magical technology, and what kind of technology can break through ultra-low temperature?
What is Ultra-Low Temperature?
So what is ultra-low temperature?
In fact, ultra-low temperature is a very extreme temperature state, which refers to a temperature state below -100°C.
The state of an object at ultra-low temperature and the state we see at room temperature are two very contrasting states.
It is well known that when the temperature is high enough, the movement of the object relative to the molecules will be very fast, and the speed of movement will be faster, and it will be possible to change the substance from a liquid state to a gaseous state.
When the temperature is low enough, the movement of molecules will become slow, and slow molecular movement may change the substance from liquid to solid, and temperatures below -100°C may cause some substances to completely stop their molecular motion.
At this time, there is a special temperature called absolute zero.
Absolute zero, or -273.15°C, is also a very important temperature in thermodynamics.
At this temperature, the molecules of no substance are able to move more, because the thermal motion of the molecules causes the temperature to rise when the temperature rises, and the temperature decreases when the temperature decreases, which is also a unique property of temperature.
Breakthrough technology for ultra-low temperatures.
For humans, absolute zero is a temperature that can never be reached.
But the human understanding of this temperature is not exhaustive.
In 1968, scientists experimentally cooled a chemical element called cesium to a temperature closest to absolute zero, which was 0.000001 degrees.
At this time, scientists observed a very peculiar phenomenon on a cesium sample through experiments, that is, a very special number of electrons in the cesium sample condensed together to form a new state.
This state is due to the fact that the temperature of the cesium sample is reduced to a very low level, causing the molecules in the cesium sample to stop moving, so these electrons will naturally no longer be free, but will condense together, forming a new state, and finally cesium becomes a new substance.
Since then, human beings have studied this material many times, and similar phenomena have been found on many materials.
After the 21st century, this ultra-low temperature technology began to be used in human life.
Superconducting magnets composed of many highly compressed titanium alloys were invented.
It can form an extremely low temperature environment at extremely low temperatures, which has a very good effect on some superconducting materials at low temperatures.
This makes superconducting magnets very widely used in modern nuclear magnetic resonance equipment.
In 2020, a company called Shanghai Qiushi Superconducting Technology announced that they had successfully developed a very special ultra-low temperature refrigeration technology.
This technology not only breaks the temperature record for cesesium samples in terms of temperature, but also has a temperature difference of less than 0.01 degrees from absolute zero.
The key to a breakthrough.
In fact, if you want to break through ultra-low temperature, the key is not to reduce the temperature, but to make the temperature of matter close to absolute zero, then the thermal motion of the material molecules is needed to give the movement energy of the material molecules.
It's like throwing a ribbon and a thin wire.
Let's compare, if a ribbon does not have the action of an external force, it will not stand up.
But a thin wire can stand up very easily.
This is because the molecular motion on the ribbon and the wire gives them different forces in the position they occupy.
At a temperature of absolute zero, the energy of the molecule is very low.
This leads to the third law of thermodynamics, which states that when the temperature drops, the energy of the molecule also decreases.
When the temperature drops to the limit, the molecules with very low energy return to their basic state and stop their thermal motion.
It's hard to find anything that stops the thermal motion more easily than these molecules, so if we want to bring matter closer to absolute zero, we need lower temperatures.
The most primitive way to achieve a low temperature is by evaporation.
The temperature of the evaporated substance naturally decreases, so the best way to do this is to evaporate the substance with a high degree of decompression.
Liu Xiaoping of Shanghai Qiushi Superconducting Technology revealed in his blog how they did it.
In the 70s of the last century, they collected a gas that is very sensitive to decompression.
This gas is called nitrogen.
At that time, scientists had already discovered that it was a very good decompression tool, and that his heat of dissolution was very high.
This causes the temperature of the water to be reduced to extreme temperatures after decompression evaporation, so this substance is also used by scientists as a refrigeration technology to cool the substance.
epilogue
The emergence of this technology is of great help to our future research and development, and it is a very good breakthrough at the end of the technology, and it can also be said to be a very significant breakthrough.
So I hope he can get better and better and bring more benefits to the society, and I also hope that the content of the editor can be helpful to you.