In applications such as nuclear reactors, a neutron poison (also called a neutron absorber or a nuclear poison) is a substance with a large neutron absorption cross-section. [1] In such applications, absorbing neutrons is normally an undesirable effect.

2021年3月9日 · Nuclear poison (or neutron poison) In reactor physics, a substance (other than fissionable material) that has a large capacity for absorbing neutrons in the vicinity of the reactor core. This effect may be undesirable in some reactor applications because it may prevent or disrupt the fission chain reaction, thereby affecting normal operation.

2024年2月13日 · Radiation sickness also is called acute radiation syndrome or radiation poisoning. Radiation sickness is not caused by common medical imaging tests that use low-dose radiation, such as X-rays, CT scans and nuclear medicine scans. Although radiation sickness is serious and often fatal, it's rare.

Neutron poisons are fission products that are of concern in reactors primarily because they become parasitic absorbers of neutrons and result in long-term sources of heat (so-called decay heat). Their buildup in the reactor tends to reduce the multiplication factor. Nuclear fission fragments are the fragments left after a nucleus fissions.

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.

135 Xe is a fission product of uranium and it is the most powerful known neutron-absorbing nuclear poison (2 million barns; [1] up to 3 million barns [1] under reactor conditions [2]), with a significant effect on nuclear reactor operation.

A nuclear poison, also called a neutron poison is a substance with a large neutron absorption cross-section in applications, such as nuclear reactors, when absorbing neutrons is an undesirable effect. However neutron-absorbing materials, also called poisons, are intentionally inserted into some types of reactors in order to lower the high ...

Some of the fission products generated during fission have a high neutron absorption capacity, such as xenon-135 and samarium-149. The poisoning of a reactor by fission products may become so serious that the chain reaction comes to a standstill.

The iodine pit, also called the iodine hole or xenon pit, is a temporary disabling of a nuclear reactor due to buildup of short-lived nuclear poisons in the reactor core. The main isotope responsible is 135 Xe , mainly produced by natural decay of 135 I .

The accident was sparked when the nuclear reactor was shut down for testing at low power, 720 MW. Xe-135 poisoning started to accumulate on the fuel rods and the thermal power kept decreasing to 30 MW.