Difference between revisions of "Pressure"
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|description='''Pressure''' [Pa = J·m<sup>-3</sup>] is the concentration of the [[force]] at the point of [[action]]. More generally, pressure is the force times concentration at the interphase of interaction. | |description='''Pressure''' [Pa = J·m<sup>-3</sup>] is the concentration of the [[force]] at the point of [[action]]. More generally, pressure is the force times concentration at the interphase of interaction. | ||
In addition to mechanical pressure, hydrostatic pressure, barometric pressure, partial gas pressure ([[oxygen pressure]]), isomorphic pressures are distinguished as [[osmotic pressure]], [[diffusion pressure]], [[reaction pressure]], and even [[electric pressure]]. In the classical physicochemical literature, there is some confusion between the terms force and pressure: ''"This force is called the pressure of the gas"'' by [[Maxwell 1867 Phil Trans Royal Soc London |Maxwell (1867)]]; ''"Pressure forces"'' by [[Einstein 1905 Ann Physik 549 |Einstein (1905)]]; presentation of ''Fick's law of diffusion'' (which represents a flux-pressure relationship) as a flux-force relationship by [[Prigogine 1967 Interscience |Prigogine (1967)]]. | In addition to mechanical pressure, hydrostatic pressure, barometric pressure, partial gas pressure ([[oxygen pressure]]), isomorphic pressures are distinguished as [[osmotic pressure]], [[diffusion pressure]], [[reaction pressure]], and even [[electric pressure]]. In [[ergodynamics]], the pressure in a transformation tr is the product of [[free activity]] times [[force]], Δ<sub>tr</sub>''Π'' = ''α''<sub>tr</sub>·Δ<sub>tr</sub>''Π'' [mol·L<sup>-1</sup> · kJ·mol<sup>-1</sup> = kJ·L<sup>-1</sup> = kJ·dm<sup>-3</sup> = MJ·m<sup>-3</sup> = MPa]. | ||
In the classical physicochemical literature, there is some confusion between the terms force and pressure: ''"This force is called the pressure of the gas"'' by [[Maxwell 1867 Phil Trans Royal Soc London |Maxwell (1867)]]; ''"Pressure forces"'' by [[Einstein 1905 Ann Physik 549 |Einstein (1905)]]; presentation of ''Fick's law of diffusion'' (which represents a flux-pressure relationship) as a flux-force relationship by [[Prigogine 1967 Interscience |Prigogine (1967)]]. | |||
|info=[[Gnaiger 1989 Energy Transformations]]; [[Gnaiger 2017 MiP2017]] | |info=[[Gnaiger 1989 Energy Transformations]]; [[Gnaiger 2017 MiP2017]] | ||
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Revision as of 00:25, 24 August 2018
- high-resolution terminology - matching measurements at high-resolution
Pressure
Description
Pressure [Pa = J·m-3] is the concentration of the force at the point of action. More generally, pressure is the force times concentration at the interphase of interaction.
In addition to mechanical pressure, hydrostatic pressure, barometric pressure, partial gas pressure (oxygen pressure), isomorphic pressures are distinguished as osmotic pressure, diffusion pressure, reaction pressure, and even electric pressure. In ergodynamics, the pressure in a transformation tr is the product of free activity times force, ΔtrΠ = αtr·ΔtrΠ [mol·L-1 · kJ·mol-1 = kJ·L-1 = kJ·dm-3 = MJ·m-3 = MPa].
In the classical physicochemical literature, there is some confusion between the terms force and pressure: "This force is called the pressure of the gas" by Maxwell (1867); "Pressure forces" by Einstein (1905); presentation of Fick's law of diffusion (which represents a flux-pressure relationship) as a flux-force relationship by Prigogine (1967).
Abbreviation: P, p, Π
Reference: Gnaiger 1989 Energy Transformations; Gnaiger 2017 MiP2017
MitoPedia concepts:
MiP concept,
Ergodynamics
