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Adiabatic ionization is a form of ionization in which an electron is removed from or added to an atom or molecule in its lowest energy state to form an ion in its lowest energy state. [16] The Townsend discharge is a good example of the creation of positive ions and free electrons due to ion impact.
Radiolysis is the dissociation of molecules by ionizing radiation.It is the cleavage of one or several chemical bonds resulting from exposure to high-energy flux.The radiation in this context is associated with ionizing radiation; radiolysis is therefore distinguished from, for example, photolysis of the Cl 2 molecule into two Cl-radicals, where (ultraviolet or visible spectrum) light is used.
Malformations generally occur after organogenesis. [8] This is the phase of development where the three germ layers (the ectoderm, endoderm, and mesoderm) form the internal organs of the fetus. [24] The estimated dose threshold is 0.1 Gylow-linear-energy-transfer (LET) radiation, and this period generally occurs from day 14–50. [8]
When radiation deposits enough energy in organic tissue to cause ionization, this tends to break molecular bonds, and thus alter the molecular structure of the irradiated molecules. Less energetic radiation, such as visible light, only causes excitation, not ionization, which is usually dissipated as heat with relatively little chemical damage ...
Ionization of molecules can lead to radiolysis (breaking chemical bonds), and formation of highly reactive free radicals. These free radicals may then react chemically with neighbouring materials even after the original radiation has stopped (e.g. ozone cracking of polymers by ozone formed by ionization of air). Ionizing radiation can also ...
The DART ionization process can produce positive or negative ions depending on the potential applied to the exit electrode. This ionization can occur for species desorbed directly from surfaces such as bank notes, tablets, bodily fluids (blood, saliva and urine), polymers, glass, plant leaves, fruits & vegetables, clothing, and living organisms.
Atmospheric-pressure chemical ionization (APCI) is an atmospheric pressure technique that can be applied to all the above separation techniques. APCI is a gas phase ionization method, which provides slightly more aggressive ionization than ESI which is suitable for less polar compounds.
The ionization occurs in the gas phase, unlike ESI, where the ionization occurs in the liquid phase. A potential advantage of APCI is that it is possible to use a nonpolar solvent as a mobile phase solution, instead of a polar solvent, because the solvent and molecules of interest are converted to a gaseous state before reaching the corona ...