One breadth of analysis in which abrasion abstracts acerb is in ultrasound physics. Abrasion in ultrasound is the abridgement in amplitude of the ultrasound axle as a action of ambit through the imaging medium. Accounting for abrasion furnishings in ultrasound is important because a bargain arresting amplitude can affect the superior of the angel produced. By alive the abrasion that an ultrasound axle adventures traveling through a medium, one can acclimatize the ascribe arresting amplitude to atone for any accident of activity at the adapted imaging depth.2
Ultrasound abrasion altitude in amalgamate systems, like emulsions or colloids, yields advice on atom admeasurement distribution. There is an ISO accepted on this technique.3
Ultrasound abrasion can be acclimated for analytic rheology measurement. There are acoustic rheometers that apply Stokes' law for barometer analytic bendability and aggregate viscosity.
edit Abrasion coefficient
Attenuation coefficients are acclimated to quantify altered media according to how acerb the transmitted ultrasound amplitude decreases as a action of frequency. The abrasion accessory (α) can be acclimated to actuate absolute abrasion in dB in the boilerplate application the afterward formula:
\text{Attenuation} = \alpha \text{dB}/(\text{MHz cm}) \cdot \ell \text{cm} \cdot \text{f}\text{MHz}
As this blueprint shows, besides the boilerplate breadth and abrasion coefficient, abrasion is aswell linearly abased on the abundance of the adventure ultrasound beam. Abrasion coefficients alter broadly for altered media. In biomedical ultrasound imaging however, biological abstracts and baptize are the a lot of frequently acclimated media. The abrasion coefficients of accepted biological abstracts at a abundance of 1 MHz are listed below:4
Material \alpha (\text{dB}/(\text{MHz}\cdot\text{cm}))
Blood 0.2
Bone, cortical 6.9
Bone, trabecular 9.94
Brain 0.6
Breast 0.75
Cardiac 0.52
Connective tissue 1.57
Dentin 80
Enamel 120
Fat 0.48
Liver 0.5
Marrow 0.5
Muscle 1.09
Tendon 4.7
Soft tissue (average) 0.54
Water 0.0022
There are two accepted means of acoustic activity losses: assimilation and scattering, for instance ablaze scattering.5 Ultrasound advancement through constant media is associated alone with assimilation and can be characterized with assimilation accessory only. Advancement through amalgamate media requires demography into annual scattering.6
Ultrasound abrasion altitude in amalgamate systems, like emulsions or colloids, yields advice on atom admeasurement distribution. There is an ISO accepted on this technique.3
Ultrasound abrasion can be acclimated for analytic rheology measurement. There are acoustic rheometers that apply Stokes' law for barometer analytic bendability and aggregate viscosity.
edit Abrasion coefficient
Attenuation coefficients are acclimated to quantify altered media according to how acerb the transmitted ultrasound amplitude decreases as a action of frequency. The abrasion accessory (α) can be acclimated to actuate absolute abrasion in dB in the boilerplate application the afterward formula:
\text{Attenuation} = \alpha \text{dB}/(\text{MHz cm}) \cdot \ell \text{cm} \cdot \text{f}\text{MHz}
As this blueprint shows, besides the boilerplate breadth and abrasion coefficient, abrasion is aswell linearly abased on the abundance of the adventure ultrasound beam. Abrasion coefficients alter broadly for altered media. In biomedical ultrasound imaging however, biological abstracts and baptize are the a lot of frequently acclimated media. The abrasion coefficients of accepted biological abstracts at a abundance of 1 MHz are listed below:4
Material \alpha (\text{dB}/(\text{MHz}\cdot\text{cm}))
Blood 0.2
Bone, cortical 6.9
Bone, trabecular 9.94
Brain 0.6
Breast 0.75
Cardiac 0.52
Connective tissue 1.57
Dentin 80
Enamel 120
Fat 0.48
Liver 0.5
Marrow 0.5
Muscle 1.09
Tendon 4.7
Soft tissue (average) 0.54
Water 0.0022
There are two accepted means of acoustic activity losses: assimilation and scattering, for instance ablaze scattering.5 Ultrasound advancement through constant media is associated alone with assimilation and can be characterized with assimilation accessory only. Advancement through amalgamate media requires demography into annual scattering.6
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