e0e e62 977 0a8 8af da2 1b6 bf0 655 229 85d 9ca 309 5e5 1da 6f8 2fc 015 113 2e6 53f c3c 6e3 1ae 44b 9bb 2d0 661 5c8 9e9 ffd 8a5 c57 a05 e6a 66e d1c 563 5e8 683 663 25a 304 c06 cef ce2 34b 785 f5b 5a5 a66 bda c4e a1f d86 235 baf 741 9b1 8de 25a a97 831 e4a f8c 0cd e1a 783 4b1 b6d 18a 7ec cf8 f27 a4c ca2 f56 9c5 aef 3a2 81f 15a cb1 7c1 19a 10b b96 fee abe 696 6da cbe 6e8 5c1 142 e7f 89a 7c6 79d 0ea
In reactor physics, a substance (other than fissionable material) that has a large capacity for absorbing neutrons in the vicinity of the reactor core.
What poisons a nuclear reactor?
poison, in nuclear physics, any material that can easily capture neutrons without subsequently undergoing nuclear fission. Examples of poisons are the naturally occurring elements boron and cadmium and the fission products xenon-135 and samarium-149.
What poisoned the Chernobyl reactor?
Xenon poisoning Xenon poisoning was a contributing factor to the Chernobyl disaster; during a run-down to a lower power, a combination of operator error and xenon poisoning caused the reactor thermal power to fall to near-shutdown levels.
Why xenon is poison in reactor?
Transient fission product poisons The poisoning of a reactor core by these fission products may become so serious that the chain reaction comes to a standstill. Xenon-135 in particular tremendously affects the operation of a nuclear reactor because it is the most powerful known neutron poison.
What is the purpose of using reactor shielding?
Shields are also used in some reactors to reduce the intensity of gamma rays or neutrons incident on the reactor vessel. This radiation shielding protects the reactor vessel and its internals (e.g.,, the core support barrel) from excessive heating due to gamma-ray absorption fast neutron moderation.
How did xenon build up in Chernobyl?
Because Xenon built up due to a rapid shut-down mainly caused by nearby coal plant problem, operators at Chernobyl retracted the control rods all the way out of the core only to notice power instabilities due to the inherent positive coolant void coefficient of the RBMK reactor and reinsert them.
What caused the Chernobyl disaster?
The Chernobyl accident in 1986 was the result of a flawed reactor design that was operated with inadequately trained personnel. The resulting steam explosion and fires released at least 5% of the radioactive reactor core into the environment, with the deposition of radioactive materials in many parts of Europe.
Is Chernobyl reactor 4 still burning?
Chernobyl reactor 4 is no longer burning. The reactor was originally covered after the disaster, but it resulted in a leak of nuclear waste and needed to be replaced. The systems for a new cover for the reactor were being tested in 2020 and is sometimes referred to as a "sarcophagus."
Why did Russia take Chernobyl?
According to military analysts, seizing Chernobyl was a strategic decision that gave Russian troops quick and easy access to Kyiv from Belarus, which is an ally of Moscow. The ghost town in which the power plant is located is essentially placed on a direct highway to Kyiv.
What is reactor dead time?
For detection systems that record discrete events, such as particle and nuclear detectors, the dead time is the time after each event during which the system is not able to record another event.
