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How to ensure the safe operation of nuclear reactors

Nuclear energy can effectively solve the energy crisis, for economic development to provide sufficient power. But the 2011 Fukushima nuclear leak in Japan so that people increased the use of the nuclear energy crisis, then nuclear energy really safe?

A nuclear power plant is a power station that generates electricity using the energy released by nuclear fission or nuclear fusion reactions. At present, the commercial operation of nuclear power plants is using nuclear fission reaction and power generation. Nuclear power plants are generally divided into two parts: the use of atomic nuclear fission production of nuclear islands (including reactor and a loop system) and the use of steam power generation of conventional islands (including turbine generator system), the use of fuel is generally radioactive heavy metals: uranium, Plutonium Nuclear power is not only used to generate electricity but also used to make nuclear weapons, Japan is the only one by the atomic bomb attack countries, it is the great destruction of nuclear weapons, in the cold war the United States and the Soviet Union did not dare to press the nuclear weapons button.

Nuclear reactor materials to produce a controllable nuclear fission chain reaction and ensure the safe operation of various types of materials. In addition to nuclear fuel, but also includes coolant, moderator, reflective material, structural materials, control materials, and shielding materials. Nuclear reactor materials generally work in special conditions such as high temperature, corrosive media, and irradiation, so they are critical to their physical, chemical, and mechanical properties. Such as the control material used to make the nuclear reactor control rod material. The control rod compensates and regulates neutron reactivity and emergency shutdown in the reactor. The control material has the characteristics of a large absorption cross-section and small scattering cross-section.

Commonly used control materials are boron nitride powder, cadmium, hafnium, and some rare earth elements and their alloys. Boron not only has a high neutron absorption cross-section, but also a wide range of energy for absorbing neutrons, generally boron carbide or boron steel as a control material. The thermal neutron absorption cross-section of cadmium is higher than that of boron, but the absorption cross-section of superheat neutrons is small, and silver indium-cadmium alloy is generally used for water-cooled reactor. Hafnium not only has a high absorption cross-section for thermal neutrons and superheat neutrons but also a long life neutron absorber, especially for water-cooled reactors. But hafnium is scarce and expensive, so the use is limited.

Once the nuclear power plant suffered political and military attacks caused by nuclear leakage will cause serious security incidents, the former Soviet Union Chernobyl nuclear accident and Fukushima nuclear accident have caused huge casualties and property damage, nuclear leakage caused by nuclear Radiation caused serious nuclear pollution, polluted areas for decades or even hundreds of years is not suitable for human survival, Chernobyl accident deaths reached more than 90,000 people, more than 20 million people suffering from cancer, direct or indirect death It is difficult to estimate, and the long-term impact after the accident is still unknown. So nuclear power can only be limited development, and now the developed countries are gradually shut down the nuclear power plant, with cleaner and more secure energy instead.

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