Examples of radioactive tracer in the following topics:
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- A radioactive tracer is a chemical compound in which one or more atoms have been replaced by a radioisotope.
- A radioactive tracer is a chemical compound in which one or more atoms have been replaced by a radioisotope.
- The underlying principle in the creation of a radioactive tracer is that an atom in a chemical compound is replaced by another atom of the same chemical element.
- In a tracer, this substituting atom is a radioactive isotope.
- There are two main ways in which radioactive tracers are used:
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- As part of the scan, a tracer substance attached to radioactive isotopes is injected into the blood.
- When parts of the brain become active, blood (which contains the tracer) is sent to deliver oxygen.
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- In isotopic labeling, there are multiple ways to detect the presence of labeling isotopes: mass, vibrational mode, or radioactive decay.
- The radioactive decay can be detected through an ionization chamber or autoradiographs of gels.
- An isotopic tracer is used in chemistry and biochemistry to help understand chemical reactions and interactions.
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- Nuclear medicine uses certain properties of isotopes and the energetic particles emitted from radioactive material to diagnose or treat various pathology.
- The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide (tracer), which is introduced into the body on a biologically active molecule.Three-dimensional images of tracer concentration within the body are then constructed by computer analysis.A PET scan is one of the many medical uses for radioactive isotopes
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- Radioactive decay series describe the decay of different discrete radioactive decay products as a chained series of transformations.
- Radioactive decay series, or decay chains, describe the radioactive decay of different discrete radioactive decay products as a chained series of transformations.
- The intermediate stages often emit more radioactivity than the original radioisotope.
- For example, natural uranium is not significantly radioactive, but pitchblende, a uranium ore, is 13 times more radioactive because of the radium and other daughter isotopes it contains.
- Not only are unstable radium isotopes significant radioactivity emitters, but as the next stage in the decay chain they also generate radon, a heavy, inert, naturally occurring radioactive gas.
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- The emission of these rays is called nuclear radioactivity, or simply radioactivity.
- A substance or object that emits nuclear radiation is said to be radioactive.
- Uranium is radioactive whether it is in the form of an element or compound.
- Radium became highly desirable because it was about two million times as radioactive as uranium.
- Marie's radioactive fingerprints on some pages of her notebooks can still expose film.
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- Transuranium elements are those beyond uranium, none of which is stable because of radioactive decomposition.
- None of these elements is stable and each of them decays radioactively into other elements.
- Each of these elements is radioactive, with a half-life much shorter than the age of the Earth.
- Yellow - Radioactive elements: the most stable isotope has a half-life between 800 and 34.000 years.
- Very little is known about these elements due to their extreme instability and radioactivity.
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- Radiometric dating is used to date materials using the decay rate of a radioactive isotope.
- In many cases, the daughter nuclide is radioactive, resulting in a decay chain.
- The mathematical expression that relates radioactive decay to geologic time is:
- Example of a radioactive decay chain from lead-212 (212Pb) to lead-208 (208Pb) .
- Calculate the age of a radioactive sample based on the half-life of a radioactive constituent
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- Although radiation was discovered in the late 19th century, the dangers of radioactivity and of radiation were not immediately recognized.
- In the case of external exposure, the radioactive source is outside (and remains outside) the exposed organism.
- Examples of external exposure include a nuclear worker whose hands have been dirtied with radioactive dust or a person who places a sealed radioactive source in his pocket.
- In the case of internal exposure, the radioactive material enters the organism, and the radioactive atoms become incorporated into the organism.
- When radioactive compounds enter the human body, the effects are different from those resulting from exposure to an external radiation source.
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- Radioactive decay is a random process at the single-atom level; is impossible to predict exactly when a particular atom will decay.
- The following equation is used to predict the number of atoms (N) of a a given radioactive sample that remain after a given time (t):
- This relationship between the half-life and the decay constant shows that highly radioactive substances are quickly spent, while those that radiate weakly endure longer.
- A simulation of many identical atoms undergoing radioactive decay, starting with four atoms (left) and 400 atoms (right).
- Nuclear half-life is the time that it takes for one half of a radioactive sample to decay.