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Kelvin theorem

Gibbsitic [14762-49-3] Gibbs-Kelvin equation Gibbs phase rule Gibbs s phase rule Gibbs s theorem Gibbs-Thomson equation... [Pg.440]

This very important theorem was recognised by R. Clausius in 1850, although he did not at the time give the very simple interpretation, in terms of the conception of intrinsic energy, which was brought forward by Lord Kelvin a year later. [Pg.36]

In 1879 Lord Kelvin introduced the term nwtivity for the possession, the waste of which is called dissipation at constant temperature this is identical with Maxwell s available energy. He showed in a paper On Thermodynamics founded on Motivity and Energy Phil. Mag., 1898), that all the thermodynamic equations could be derived from the properties of motivity which follow directly from Carnot s theorem, without any explicit introduction of the entropy. [Pg.101]

In spite of the fact that the general statement of this principle has been shown to be false from all standpoints, it must be admitted that its enunciation was quite in harmony with the spirit of the times the great physicists Lord Kelvin (1851) and Helmholtz (1847) had previously formulated an identical principle in connection with galvanic cells. Thomsen and Berthelot went wrong, not in tlieir enunciation of the so-called theorem as a working hypothesis, but rather in their... [Pg.258]

Jochmann s equation, 164 Joule, 31 experiments with gases, 137 Kelvin effect, 164, 225 researches, 28, 51 theorem, 136... [Pg.541]

The conclusion that can be reached from the Nernst heat theorem is that the total entropy of the products and the reactants in a chemical reaction must be the same at 0 Kelvin. But nothing in the statement requires that the entropy of the individual substances in the chemical reaction be zero, although a value of zero for all reactants and products is an easy way to achieve the result of equation (4.17). [Pg.164]

One hundred fifty years ago, the two classic laws of thermodynamics were formulated independently by Kelvin and by Clausius, essentially by making the Carnot theorem and the Joule-Mayer-Helmholtz principle of conservation of energy concordant with each other. At first the physicists of the middle 1800s focused primarily on heat engines, in part because of the pressing need for efficient sources of power. At that time, chemists, who are rarely at ease with the calculus, shied away from... [Pg.583]

From Kelvin s theorem, inviscid motions in a gravity (conservative) field which are initially irrotational remain so. We may, therefore, write... [Pg.7]

This definition is consistent with the definition of the chirality of rigid molecules and forms a sufficient and necessary condition for the optical activity of NRMs. The generalization of Kelvin s theorem for NRMs may be stated as a NRM is chiral, if the group H3) 3 is properly orthogonal. [Pg.71]

Wulff s theorem [25] states that cr/r is invariant for all faces. Therefore, the result obtained from the Kelvin s equation must be independent of the choice of a face. [Pg.83]

Take care on the correct units. Try to explain the findings. There are further tests of interest Work out similarity theorems for other shapes of the molecules than spheres. Estimate whether the molecule radii obtained from the relation are in the correct range. Take notice that Lord Kelvin established such considerations [17,18]. [Pg.337]

The theory behind the third law of thermodynamics was initially formulated by Walther Nemst in 1906, which was known as Nemst theorem (https //www.sussex. ac.uk/webteam/gateway/file.php name=a-thermodynamicshistory. pdf site=35). The third law of thermodynamics was conceived from the fact that attaining absolute zero temperature is practically impossible. Lord Kelvin deduced this fact from the second law of thermodynamics with his study of heat transfer, work done, and efficiency of a number of heat engines in series. Kelvin s work was the foundation for the formulation of the third law. It can be stated as follows Absolute zero temperature is not attainable in thermodynamic processes. Another noted scientist, Max Planck, put forward the third law of thermodynamics from his observations in 1913. It states that The entropy of a pure substance is zero at absolute zero temperature. Plank observed that only pure, perfectly crystalline stmctures would have zero entropy at absolute zero temperamre. All other substances attain a state of minimum energy at absolute zero temperature as the molecules of the substance are arranged in their lowest possible energy state. [Pg.87]

This leads to Kelvin s circulation theorem, which states that for a barotropic fluid with no frictional forces acting, the absolute circulation is conserved following the motion. [Pg.230]

The vorticity equation describes how vorticity is changed by various properties of the flow. Only in very special circumstances would the vorticity be conserved following the flow. Kelvin s circulation theorem describes how an integral measure of vorticity is conserved but is valid only for barotropic flow and furthermore requires a knowledge of the time evolution of material surfaces. There does exist a quantity, referred to as the Ertel potential vorticity, that is conserved under more general conditions than either the vorticity or the circulation. It may be shown by combining the curl of the momentum equation [Eq. (26a)] with the continuity equation [Eq. (26c)] and the thermodynamic equation [Eq. (26b)] expressed in terms of potential temperature 0 that... [Pg.230]

Third Law of Thermodynamics The third law of thermodynamics was developed by Nemst and is referred to as the Nernst postulate or Nernst theorem. It states that entropy of pure substances approach zero when the temperature of the substance is brought to 0 Kelvin. [Pg.328]

Assuming that H(Y X) < 0 [information variant of Kelvin s formulation of the 11. Principle of Thermodynamics for irreversible cyclical transfer O when the respective relation (34) is valid], we also have the information variant of the second part of Carnot s theorem... [Pg.94]

The practical interest of discriminating between flows based on their rotational or irrotational character results from Kelvin s theorem, one main consequence of which is that, in the absence of viscosity, it is impossible for an irrotational flow to spontaneously become rotational. Vorticity can only be produced in a flow at the boundaries of the domain, through the action of viscosity. It only appears within the fluid by transport or diffusion from the boundaries. Vorticity is produced in boundary layers near the walls. [Pg.361]

The second restriction within which we shall place ourselves is that of high-Reynolds-number flows, that is, Re = FR / v 1. V is the velocity scale of the azimuthal component and R is a characteristic dimension of the flow in the Oxy plane. Viscosity will therefore be negligible outside the boimdary layers, and the properties resulting from Kelvin s theorem will be applicable. [Pg.363]

At high Reynolds numbers, if transit through the apparatus is fast, vorticity does not have enough time to diffuse. Kelvin s theorem resirlts in the flow being irrotational in the part of the apparatus through which the flow passes. It is therefore also irrotational in the outlet sectiorts (spigot and overflow). This resirlt has two consequences ... [Pg.370]


See other pages where Kelvin theorem is mentioned: [Pg.71]    [Pg.834]    [Pg.71]    [Pg.834]    [Pg.65]    [Pg.63]    [Pg.903]    [Pg.903]    [Pg.198]    [Pg.199]    [Pg.70]    [Pg.39]    [Pg.80]    [Pg.410]    [Pg.443]    [Pg.834]    [Pg.81]    [Pg.84]    [Pg.787]    [Pg.8]    [Pg.5]    [Pg.563]    [Pg.90]    [Pg.72]    [Pg.72]    [Pg.77]    [Pg.359]   
See also in sourсe #XX -- [ Pg.235 ]




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