Short this text 1. The absorbed dose (irradiation dose) At hit ionizing radiations on any body it is important to value the action of this radiation. Energy of the ionizing radiations partly converts in energy of molecular heat motion of bodies. The absorbed dose (irradiation dose) is a main physical value, accepted in dosimetry to estimate influence of the ionizing radiations on all objects including living organisms); D=Delta E/m, (1) D is the absorbed dose (irradiation dose), AE - energy, m =the mass of a body. The unit of measurement of the absorbed dose is Gy (gray) in SI: 1Gy=(1J)/(1kg) . This unit of measurements has a name of the English radiobiologist Gray. In a real experiment another unit is used - rad: 1 rad=10^-2Gy. Abbreviation rad means "radiated absorbed dose". We often want to know the absorbed dose in a unit of time. So there is a power of dose.It is a ratio the dose to time interval of irradiation -D/Delta t. The main unit of this value is Gy/s in SI; the other unit of dose power is rad/s. 2. Exposure (air) dose for the photon radiation. There is a very important problem about calculation of energy of the ionizing radiations, which absorbed by a body . The absorbed dose isn't convenient for this purpose.The bodies, absorbing the ionizing radiations, are not homogenous.Both absorption and reflection of the falling ionizing radiations occur so it is difficult to determine the true dose. The ionizing effect, caused by the ionizing radiation in the air, surrounding a body, is easier to take into account The exposure (air) dose is used for the effectiveness photon radiations (X. ray and y-radiations). Exposure (air) dose X is valued by the charge of ions of the same sign, which are formed midair, surrounding a body, under the action of X-ray and y-radiations. X=dQ/dm, dQ - a total charge of ions of the same sign, created in the air under the action of photon radiations in the elementary volume; dm the mass of air in this volume. The unit of measure of the exposure dose is C/kg in SI. 1 C/kg - is such an exposure (air) dose, when all ions, formed by photons in I kg of dry air, carry electric charge IC (Coulomb) for each sign. Non-SI unit of measure is Roentgen (R) Roentgen corresponds to the charge, forming in 1cm^3 of dry air. 1R=2.58times 10^-4 C/kg. There is a straight proportional dependency between the air dose and the absorbed dose: D=fX, (3) f - factor, which depends on material and kind of radiation f=1 for soft tissues and water, if D is expressed in rad, X-in Roentgen . For air ff=0,88 N/M-power of an air dose. It's a unit of measure in SI is C/(kgtimes s) or A/kg The power of an exposure dose is connected with the activity of a radioactive substance (A): X/Delta t=K_(y)A/r^2, K, - is a y-constant.depends on a type of the substance (radioactive nuclide). A-is activity of the substance. r= is a distance from the source of radiations to the place, where the air dose is measured, Delta t-is time of influence ionizing radiations on object Hence: X=K_(r)ADelta t/r^2

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Short this text 1. The absorbed dose (irradiation dose) At hit ionizing radiations on any body it is important to value the action of this radiation. Energy of the ionizing radiations partly converts in energy of molecular heat motion of bodies. The absorbed dose (irradiation dose) is a main physical value, accepted in dosimetry to estimate influence of the ionizing radiations on all objects including living organisms); D=Delta E/m, (1) D is the absorbed dose (irradiation dose), AE - energy, m =the mass of a body. The unit of measurement of the absorbed dose is Gy (gray) in SI: 1Gy=(1J)/(1kg) . This unit of measurements has a name of the English radiobiologist Gray. In a real experiment another unit is used - rad: 1 rad=10^-2Gy. Abbreviation rad means "radiated absorbed dose". We often want to know the absorbed dose in a unit of time. So there is a power of dose.It is a ratio the dose to time interval of irradiation -D/Delta t. The main unit of this value is Gy/s in SI; the other unit of dose power is rad/s. 2. Exposure (air) dose for the photon radiation. There is a very important problem about calculation of energy of the ionizing radiations, which absorbed by a body . The absorbed dose isn't convenient for this purpose.The bodies, absorbing the ionizing radiations, are not homogenous.Both absorption and reflection of the falling ionizing radiations occur so it is difficult to determine the true dose. The ionizing effect, caused by the ionizing radiation in the air, surrounding a body, is easier to take into account The exposure (air) dose is used for the effectiveness photon radiations (X. ray and y-radiations). Exposure (air) dose X is valued by the charge of ions of the same sign, which are formed midair, surrounding a body, under the action of X-ray and y-radiations. X=dQ/dm, dQ - a total charge of ions of the same sign, created in the air under the action of photon radiations in the elementary volume; dm the mass of air in this volume. The unit of measure of the exposure dose is C/kg in SI. 1 C/kg - is such an exposure (air) dose, when all ions, formed by photons in I kg of dry air, carry electric charge IC (Coulomb) for each sign. Non-SI unit of measure is Roentgen (R) Roentgen corresponds to the charge, forming in 1cm^3 of dry air. 1R=2.58times 10^-4 C/kg. There is a straight proportional dependency between the air dose and the absorbed dose: D=fX, (3) f - factor, which depends on material and kind of radiation f=1 for soft tissues and water, if D is expressed in rad, X-in Roentgen . For air ff=0,88 N/M-power of an air dose. It's a unit of measure in SI is C/(kgtimes s) or A/kg The power of an exposure dose is connected with the activity of a radioactive substance (A): X/Delta t=K_(y)A/r^2, K, - is a y-constant.depends on a type of the substance (radioactive nuclide). A-is activity of the substance. r= is a distance from the source of radiations to the place, where the air dose is measured, Delta t-is time of influence ionizing radiations on object Hence: X=K_(r)ADelta t/r^2

Answer 1

1. The absorbed dose (irradiation dose) is a measure of the energy deposited by ionizing radiation in a unit mass of a material. It is calculated as the ratio of the energy absorbed to the mass of the material, with the unit being Gy (gray) in the SI system. Another unit used in real experiments is rad, where 1 rad equals 10^-2 Gy. The absorbed dose can also be expressed as a function of time, with the unit being Gy/s or rad/s.2. The exposure (air) dose is a measure of the ionizing effect of photon radiation in the air surrounding a body. It is calculated as the charge of ions of the same sign formed in the air under the action of X-ray and y-radiations. The unit of measure for the exposure dose is C/kg in the SI system, with another non-SI unit being the Roentgen (R), which corresponds to the charge formed in 1 cm^3 of dry air. The exposure dose is proportional to the absorbed dose, with the factor of proportionality depending on the material and type of radiation. The power of an exposure dose is connected to the activity of a radioactive substance and is measured in C/(kg·s) or A/kg.

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