The realization of a controllable nuclear fusion reaction and the creation of an "artificial sun" is the world's hope because it can solve the problem of human energy shortage once and for all. The exciting thing is that "artificial sun" is expected to gradually turn from a dream to a reality. A few days ago, China's new generation of "artificial sun" experimental device 2012 physics experiment was successful, creating two world records. "Artificial sun" The ultimate dream of energy "Artificial Sun" - This ultimate human dream of energy, sounds too sci-fi. The principle of "artificial sun" is not mysterious. As early as several decades ago, with the discovery of nuclear physics, mankind had already opened the secret of the burning of the sun, and used the enormous energy released from the atom to create atomic bombs, hydrogen bombs, and nuclear power plants. Nuclear power plants use nuclear fission technology. The extensive use of nuclear power has profoundly affected the energy landscape of today's world. Unfortunately, although nuclear fission technology is easy to achieve, it still has many shortcomings: radioactive pollution, nuclear waste generation, and the limited reserves of heavy metals such as uranium-235 used to produce nuclear fission on the Earth will constrain the nuclear power to some extent. Fission energy development. Compared with nuclear fission, nuclear fusion will provide mankind with more ideal new energy. The mass produced by unit mass fusion is several times larger than nuclear fission. Its principle is the same as the principle of solar glow and heat generation. Huge energy comes from the nuclear fusion reaction of hydrogen. From the seawater, a large amount of isotopes of hydrogen and hydrogen can be extracted, and they can generate a large amount of energy through the fusion reaction. But more than 50 years have passed, nuclear fusion power stations are still far away from us. "Nuclear fusion is much harder than nuclear fission. Nuclear fission is like tearing off a bunch of cotton, and nuclear fusion is like in the wind. It's difficult to make two very light cotton. One can imagine, "said Gong Xianzu, a researcher at the Institute of Plasma Physics at the Hefei Institute of Physical Science, Chinese Academy of Sciences. Tokamak The "magnetic cage" holds up the "sun" The prospect of "artificial sun" is infinitely beautiful and the road is full of twists and turns. The surface temperature of the sun is as high as 6,000 degrees Celsius, and the center temperature is as high as 15 million degrees Celsius. This high temperature is enough to make any object near the sun instantly become a gas. For nuclear fusion to take place on the earth, it is necessary to heat the particles to hundreds of millions of degrees Celsius. What utensils can be used to hold hundreds of thousands of degrees Celsius of high-temperature fuel? The scientist’s solution is screaming: Use a “magnetic cage†to hold the “artificial sun†in the air. "Specifically, a cage formed by a magnetic field is used to restrain the high-temperature plasma and prevent it from running out. This device is called Tokamak," said Gong Xianzu. The "artificial sun" is confined to the "magnetic cage", suspended in the air, and not in contact with objects. There is no need to worry about high-temperature melting vessels of hundreds of millions of degrees Celsius. Magnetic confinement fusion utilizes a "magnetic container", a strong magnetic field, to constrain the high-temperature plasma and, in turn, heat it up to hundreds of millions of degrees Celsius to maintain a continuous thermonuclear reaction and convert its enormous energy into electrical energy. All Tokamaks are still experimental devices for fusion basic research. They are used to verify scientists' ideas and to study various physical and engineering technical problems encountered in the future construction of reactors. “From the current point of view, we have to do experiments step by step, study its mechanism, discover many physical phenomena and possible problems, and then upgrade them.†Gong Xianzu said. According to Wan Xiangxi, academician of the Chinese Academy of Engineering and general manager of the EAST engineering project, in the future, the fusion power plant must be operated for a long time. Currently, most tokamaks in the world can only operate for a few seconds. It is only scientifically verified that controlled nuclear fusion is proceeding on principle. Pass, but can not verify the feasibility of the project. Maintaining and controlling tens of millions of degrees Celsius plasma for a long time is a great challenge. Whether it can achieve the 400-second operation required by the future ITER is currently not fully understood by scientists. It involves accurate control of the plasma. Superconducting magnets have complicated scientific and technical problems such as safe operation, effective heating and driving, strong interaction between plasma and materials. "Oriental Super Ring" Powerful scientific device It is not enough to have good ideas for light. It is difficult to turn ideas into reality. Tokamak devices impose extremely stringent requirements on human engineering technology. Among the key technologies for controlled nuclear fusion, two major issues are faced: the first is how to heat the fusion fuel to extremely high temperatures and maintain it for a long time, and the second is the issue of the “first wall†material. "The 'magnetic cage' has to confine the high-temperature plasma, but there are always some high-energy particles that run out of the edge and cannot be completely restrained, so that it will have a strong interaction with the 'first wall' and can imagine hundreds of millions of The high-temperature particles in Celsius hit the 'first wall' and will cause the material to ablate." Gong Xianzu said that this is the most harsh material that humans have developed so far. At present, the high heat radiation zone of China's Tokamak device uses a silicon carbide-coated graphite material with its own intellectual property rights. However, carbon materials have a disadvantage that it is activated by neutrons. The candidate material for the first wall of the future fusion reactor is tungsten metal. Now two professional fusion institutes in China are working with universities to test future new materials. “The long-term operation of future fusion power plants can only be realized on fully superconducting tokamaks, which is necessary to verify the feasibility of engineering and is also the development direction of future magnetic confinement fusion. China has entered the international frontier in this direction. "Millions and hee said. The world's first superconducting tokamak device is our country's EAST. It is the English abbreviation of the advanced superconducting tokamak experimental device. It also has a loud and profound Chinese name "Oriental Super Ring." It is too early to build a commercial fusion reactor. It is understood that in the 90s of last century, scientists estimated that it would take 50 years; now 20 years have passed, and scientists' estimation will still take 50 years. “My greatest wish is to see that in my lifetime, a light bulb is lightened by fusion energy,†said Li Jiangang, director of the Institute of Plasma Physics at the Chinese Academy of Sciences' Hefei Institute of Physical Science. Science Island The Dreamcatcher in "Peach Blossom Source" The Hefei Institute of Physical Science of the Chinese Academy of Sciences is located on the island of Science and Technology, a small island on the scenic bank of Lake Lushan in the western suburbs of Hefei. In this isolated "Peach Blossom Source", there are a group of "dreamcatchers" who have worked tirelessly for their ideals. The “Man-made Sun†dream has been a long and arduous journey. If it does not endure the loneliness and dedication of a strong heart, how can we make such achievements! In order to develop the East Super Ring (EAST) superconducting Tokamak Science and Technology Institute, the Institute conducted experiments day and night. Everyone turned on 24 hours a day and was on standby at any time; overtime had become commonplace and was often called up in the middle of the night. Many people started experimenting to distinguish between day and night, and they both stayed in the lab. Gong Xianzu, a researcher at the Institute of Plasma Physics of the Chinese Academy of Sciences' Hefei Institute of Physical Physics, laughed and said that he had the greatest ability—say, sleeping and lying on a sofa in a conference room. He could sleep with a military coat, but as long as the experimental horn Call immediately wake up. “Eastern Chaohuan†is an extremely “burning money†project. The electricity charge for one day is as high as 50,000 yuan, plus the cost of various expenses is as high as 100,000 yuan a day, and an annual operating fee of about 36 million yuan is required. Even so, relative to such a vast project, the funding is still very limited. The device has a small part microwave window used to isolate the vacuum and air and perform high-power microwave transmission. It looks very inconspicuous, but the sealing process requirements for ceramic sheets and metal are very strict. There is no domestic import from abroad. For $25,000, 48 will be used at a time. It is also a wearing part. If it is broken, then the import will be delayed. Liu Qikun, a researcher at the Institute of Plasma Physics, led the young people Wang Xiaojie, Liu Liang, and Zhao Lianmin to solve the problem by designing and developing their own. Each cost was reduced to 20,000 yuan, and it can be processed at any time according to need, saving the country. Millions of dollars in research funding. China Academy of Engineering and General Manager of EAST Engineering Project Yuan Xie said that with the strength of national strength and the country’s opening up, a group of talented professionals has grown rapidly, which is crucial for China’s future fusion research. Because fusion research is not a generation of people can achieve, the dream of "artificial sun" will require continuous efforts of several generations to become a reality. The efforts of the Chinese people have won the respect of the entire world. The achievements of the "Eastern Super Ring" have been regarded as a miracle by the international fusion community. Wan Xihui said that the world’s most famous institutes are actively pursuing extensive exchanges and cooperation with the Institute of Plasma Physics of the Chinese Academy of Sciences and the Chinese magnetic confinement fusion community. “Our advantage is that the country attaches importance to and supports continuous stability. Our results are the results of scientific researchers who dare to challenge, innovate, and form a large scientific and cultural team.†Wan Xie is full of the team he leads. pride. Poplar Plywood is a type of plywood that is made from poplar wood, which is a lightweight and relatively soft hardwood. It is commonly used in various construction and woodworking projects due to its affordability, versatility, and ease of use. Poplar plywood wholesale,Poplar Plywood 4X8,Poplar Plywood For Cabinets,Poplar Plywood Sheets LINYI JIUHENG IMPORT AND EXPORT CO.,LTD , https://www.jiuhengwood.com
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