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Points critical point

Haltepunkt, m. halting point, arrest point critical point (in a curve) break. [Pg.203]

The method of Lydersen [28] is a GCM of this type to estimate the critical temperature, Tc. Other approaches to non-linear GCMs include the model of Lai et al. [29] for the boiling point, Tby and the ABC approach [30] to estimate a variety of thermodynamic properties. Further, artificial neural networks have been used to construct nonlinear models for the estimation of the normal boiling point of haloalkanes [31] and the boiling point, critical point, and acentric factor of diverse fluids [32]. [Pg.16]

As in previous simpler cases with fewer DOFs, everything begins with equilibrium points (critical points in mathematical language). We straightforwardly generalize earlier results. Let H = H p, ..., pn,q, , qn) = H x) be the Hamiltonian and suppose that F is an equilibrium point, V//(x) p = 0. We linearize motion around P, and we analyze the eigenvalues of the 2n x 2n matrix M, Eq. (4). If we have the following situation ... [Pg.235]

Triple point Critical point Boiling point... [Pg.3024]

The isotherm (plot of pressure versus volume) at the temperature Tc plays a special role in the theory of the states of matter. An isotherm behaves in accordance with the gas laws slightly below T. At certain pressure, a liquid condenses from gaseous state and is distinguishable from it by the presence of a visible interface. If, however, the compression takes place at a surface separating two phases does not appear and the volumes at each end of the horizontal part of the isotherm have merged to a single point, critical point of the gas. The temperature, pressure, and molar volume at the critical point are called the critical temperature T, critical pressure P, and critical molar volume of the substance respectively. Collectively,... [Pg.5]

In each phase diagram, the necessary data are triple point, critical point, vapor pressure of the solid or liquid at f atm (101.3 kPa), and relative densities of the solid and the liquid. The rough graphs that you draw will be helpful in making predictions but will lack accuracy for most of the data. [Pg.422]

Figure 7. Dependence of the rate constant (k ) on pressure for the Diels-Alder reaction in CO2(1) + hexane(2) mixture at 318.15 K. P-o, Pc and P denote tlie dew point, critical point, and bubble point, respectively. Figure 7. Dependence of the rate constant (k ) on pressure for the Diels-Alder reaction in CO2(1) + hexane(2) mixture at 318.15 K. P-o, Pc and P denote tlie dew point, critical point, and bubble point, respectively.
If we look at a properties chart (Table 9.10), we can see that critical performance characteristics such as boiling point, critical point, and vaporization pressures are nearly the same. The major difference is the GWP of 4 as compared to the value of 1,300 for 134a. [Pg.146]

Multi-valued and discontinuous functions often present difficulties for differentiation and integration. They are mathematically not well-behaved. There is always great difficulty, for example, in fitting an equation of state in the vicinity of critical points (critical points being both mathematical and physical discontinuities). [Pg.10]

In making a preliminary selection of feasible separator types, we find our experience to indicate that those operations marked by an a in Table 1.1 should be given initial priority unless other separation operations are known to be more attractive. To compare the preferred operations, one will find certain physical properties tabulated in handbooks and other references useful. " " These properties include those of the ptire species—normal boiling point, critical point, liquid density, melting point, and vapor pressure—as well as those involving the species and a solvent or other MSA—liquid diffusivity, gas solubility, and liquid solubility. In addition, data on thermal stability are important if elevated temperatures are anticipated. [Pg.29]

Isotherms on an A-V diagram are useful to illustrate the origin of p-V diagrams, superheated liquids and subcooled vapors in metastable states, unstable states between the spinodal points, critical points, and the requirement of mechanical stability. It is reasonable to assume that the slope of A vs. V at constant temperamre and composition is negative, because... [Pg.799]

In the AOT-water-oil system, when the temperature is increased sufficiently a cloud point (critical point) is reached. At temperatures well below this transition temperature the viscosity data are in agreement with a simple hard-sphere model. Upon approaching the critical point one first notices a relatively moderate increase of viscosity by about a factor of 4 followed by a critical divergence of viscosity very close to the cloud point. The critical divergence of such a system (with decane as oil) at the critical temperature was studied and was shown to scale almost Ising-like according to rj [ Tc - T)/Tc] with a critical exponent of 0.03 [69]. [Pg.366]

Define critical pressure, critical temperature, vapor pressure, normal boiling point, normal melting point, critical point, and triple point. (Sections 11.5 and 11.6)... [Pg.453]

No matter how it is defined, measured, or calculated, the polarity of molecules correlates with macroscopic properties such as density, miscibility/solubility, boiling point, melting point, critical point, retention time in chromatography, dilation capacity, and viscosity. [Pg.108]

Original Celsius degrees converted taking 0°C=273.15 K. - Melting point (compare below). Boiling point. Critical point. [Pg.323]

It has been shown that the principle of isomorphic critical behaviour accounts not only for the thermodynamic behaviour of mixtures near vapour-liquid critical points and near critical liquid-liquid mixing critical points, but also near special critical points, like azeotropic critical points, critical points where the critical temperature exhibits a maximum or a minimum as a function of temperature, re-entrant critical points and critical double points, depending on the values of the coefficients a,-, bi, and c,- in the expressions for the scaling fields. In this chapter we restrict ourselves to some more common cases of critical phase behaviour in mixtures. [Pg.340]


See other pages where Points critical point is mentioned: [Pg.333]    [Pg.406]    [Pg.36]    [Pg.217]    [Pg.85]    [Pg.50]    [Pg.322]    [Pg.417]    [Pg.425]    [Pg.115]    [Pg.116]    [Pg.94]    [Pg.186]    [Pg.24]    [Pg.324]    [Pg.103]    [Pg.103]    [Pg.103]    [Pg.104]    [Pg.104]    [Pg.104]    [Pg.104]    [Pg.109]    [Pg.109]    [Pg.109]    [Pg.138]    [Pg.138]    [Pg.143]    [Pg.143]   
See also in sourсe #XX -- [ Pg.27 ]




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Critical point

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