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Several fluorescent molecules can be used simultaneously (given that they do not overlap, cf. FRET), whereas with radioactivity two isotopes can be used (tritium and a low energy isotope, e.g. 33 P due to different intensities) but require special equipment (a tritium screen and a regular phosphor-imaging screen, a specific dual channel ...
Radioactive decay is a random process at the level of single atoms. According to quantum theory, it is impossible to predict when a particular atom will decay, regardless of how long the atom has existed. [2] [3] [4] However, for a significant number of identical atoms, the overall decay rate can be expressed as a decay constant or as a half-life.
This means that the design, while highly efficient, can produce thrust levels of perhaps 1.3 to 1.5 N (0.29 to 0.34 lbf), making them useful only for thrusters. In order to increase the power for medium-duration missions, engines would typically use fuels with a short half-life such as polonium-210, as opposed to the typical RTG which would use ...
Radioactive tracers are used in medical and industrial applications, as well as biological and radiation chemistry. Alpha radiation is used in static eliminators and smoke detectors. The sterilizing effects of ionizing radiation are useful for cleaning medical instruments, food irradiation, and the sterile insect technique.
The non-thermal converters, such as betavoltaic cells, extract energy directly from the emitted radiation, before it is degraded into heat; they are easier to miniaturize and do not need a thermal gradient to operate, so they can be used in small machines. Atomic batteries usually have an efficiency of 0.1–5%.
Radiation and radioactive substances are used for diagnosis, treatment, and research. X-rays, for example, pass through muscles and other soft tissue but are stopped by dense materials. This property of X-rays enables doctors to find broken bones and to locate cancers that might be growing in the body. [ 7 ]
Aluminium can capture a neutron and generate radioactive sodium-24, which has a half life of 15 hours [9] [10] and a beta decay energy of 5.514 MeV. [11] The activation of a number of test target elements such as sulfur, copper, tantalum, and gold have been used to determine the yield of both pure fission [12] [13] and thermonuclear weapons. [14]
Radiobiology experiments typically make use of a radiation source which could be: An isotopic source, typically 137 Cs or 60 Co. A particle accelerator generating high energy protons, electrons or charged ions. Biological samples can be irradiated using either a broad, uniform beam, [27] or using a microbeam, focused down to cellular or ...