Energy deposition frequencies

The discrepancy may also be caused by the approximations in the calculation of the EEDF. This EEDF is obtained by solving the two-term Boltzmann equation, assuming full relaxation during one RF period. When the RF frequency becomes comparable to the energy loss frequencies of the electrons, it is not correct to use the time-independent Boltzmann equation to calculate the EEDF [253]. The saturation of the growth rate in the model is not caused by the fact that the RF frequency approaches the momentum transfer frequency Ume [254]. That would lead to less effective power dissipation by the electrons at higher RF frequencies and thus to a smaller deposition rate at high frequencies than at lower frequencies. 

Frequency of energy deposition in volumes of dimensions similar to DNA and other biological molecules provides a method of interpretation of mechanism of radiation effects. In this method, the assumption is that radiation quality effects are mostly because of the spatial properties of the radiation on a microscopic scale. The database of absolute frequencies of energy depositions in cylindrical targets of dimensions 1-100 nm include ... 

Frequency of Energy Deposition of Events of Energy>E Gy target ... 

The volumetric power deposition calculated for bound water was appreciably greater—up to about five times—than that for free water the maximum difference occurs near the bound water relaxation frequency. This enhanced energy deposition is localized in the bound water shell and therefore may cause more damage than if it were distributed uniformly throughout the medium. But Dawkins et al. consider the enhancement of biological damage by localiza-... 

S mean binding energy of Meads on S step binding energy of Meads at a step atom-substrate binding energy lateral interaction parameter angular frequency, lateral interaction parameter deposition frequency of atoms to a site x dissolution frequency of atoms from a site x phonon frequency area of an adsorption site... 

It is this energy which eventually limits the energy deposition in the material inside the coil. When H denotes the magnitude of a rf magnetic field ffrf in particular, the sample heating depends on this equation, where the permeability p, is frequency dependent. 

Radiotoxicity depends on energy deposition in tissue or organs by the radionuclide, the specific tissue exposed to the radionuclide, and the tissue radiation sensitivity. Energy deposition by a radionuclide is a function of its emitted radiations and half-life. Biokinetic studies have identified for most radionuclides of interest the pattern of movement through the body and the effective turnover rate (the sum of the biological and radioactive turnover rates). Biokinetic information also identifies the appropriate type of sample to be collected among blood, urine, feces, saliva, breath, hair, teeth, nasal swipes, and tissue obtained incidental to unrelated operations, and collection frequency. The measured radionuclide concentrations are combined with biokinetic information to calculate the committed dose equivalent, the indicator of radiation impact on the subject (NCRP 1987b). 

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