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Density temperature dependence

Before the raw data can be fitted to a thermodynamic model it must first be converted into mass or mole fractions. This operation can be accomplished quickly using a Microsoft Excel spreadsheet that is linked to the Aspen. aprbkp file in order to obtain the solvent molecular weights and temperature dependent densities. The molar volume of Form A Cimetidine is also required for this conversion, however, as is often the case it was not available so a density of 1 g/ml has been assumed. [Pg.61]

More insight into these processes is obtained by studying the particle number dependent properties of density functionals. This of course requires a suitable definition of these density functionals for fractional particle number. The most natural one is to consider an ensemble of states with different particle number (such an ensemble is for instance obtained by taking a zero temperature limit of temperature dependent density functional theory [84]). We consider a system of N + co electrons where N is an integer and 0 < m < 1. For the corresponding electron density we then have... [Pg.142]

In a numerical solution, we can include temperature dependent density and thermal conductivity. The temperature dependent density can be modeled interpolating throughout a pvT diagram. The temperature dependence of the thermal conductivity is not always available, as is the case for many properties used in modeling. Chapter 2 presents the Tait equation, which can be used to model the pvT behavior of a polymer. [Pg.412]

So the highest occupied Kohn-Sham orbital has a fractional occupation number to. The fact that is uniquely defined by follows directly from the Hohenberg-Kohn theorem applied to the non-interacting system. The proof of the Hohenberg-Kohn theorem for systems with noninteger number of electrons proceeds along the same lines as for systems with integer particle number (alternatively it can be obtained from the zero temperature limit of temperature dependent density functional theory [82]). We further split up v, as... [Pg.143]

Figure 2.1. Temperature-dependent density of liquid water at various pressures. Note the shifting of TMD to the lower temperature as pressure is inereased. (Adapted with permission from http //www.engineeringtoolbox.com/fluid-density-temperature-pressure-d 309.html.)... Figure 2.1. Temperature-dependent density of liquid water at various pressures. Note the shifting of TMD to the lower temperature as pressure is inereased. (Adapted with permission from http //www.engineeringtoolbox.com/fluid-density-temperature-pressure-d 309.html.)...
Convection convective heat transfer occurs between an object and a fluid in contact with the object. In clothing science, the fluid is usually air or water. The convective heat transfer can he classified as free convection where the flow is caused by buoyancy forces due to temperature-dependent density differences in the fluid and forced convection when the... [Pg.197]

Figure 6.3 plots the temperature-dependent density of 5CB [23]. At room temperature, the density of 5CB is around 1.02 g/cm, slightly heavier than that of water because of its higher molecular weight. As the temperature increases, the density decreases almost linearly. Due to the second-order phase transition, a disrupt density change occurs at T 353°C. In the isotropic state, the 5CB density continues to decrease linearly as the temperature increases. [Pg.197]

Minimum Energy Gap (eV) dEg/dT X dEg/dP X Density of States Electron Effective Electron Mobility and Temperature Dependence Density of States Hole Effective Role Mobility and Temperature Dependence ... [Pg.358]

Investigations have been made [26,27] into the stabihty of a liquid layer with limited thickness bounded by a cylinder with a circular or rectangular lateral cross section, this layer having an upper interface common with the bulk of an unmovable gas and the side wall of the cylindrical container being heat-proof, provided the bottom wall is maintained at a higher temperature then the upper one. Within the framework of the Boussinesq approximation for a temperature-dependent density it was found that the limit of the capillary number is close to zero = is the dynamic... [Pg.63]

If the possibility of tunneling is taken into account, then the discussion becomes much more complicated and rests on the matrix elements of the temperature-dependent density operator exp(-fl/kT). The role of the local perturbation can then be illustrated by the considering only one proton and one hydrogen bridge ... [Pg.323]

The modeling of the (temperature dependent) densities is described briefly in Sect. 6.1.2, using equations of state (EoS) derived from various modifications of the statistical associated fluid theory (SAFT), the COSMO-RS model, the Sanchez-Lascomb lattice fluid model (SL), or the perturbed hard sphere model (PHS). Each... [Pg.150]

Preiss UPRM, Slattery JM, Krossing I (2009) hi silico prediction of molecular volumes, heat capacities, and temperature-dependent densities of ionic liquids. Ind Eng Chem Res 48 2290-2296... [Pg.199]


See other pages where Density temperature dependence is mentioned: [Pg.638]    [Pg.143]    [Pg.341]    [Pg.12]    [Pg.101]    [Pg.463]    [Pg.785]    [Pg.793]    [Pg.642]    [Pg.372]    [Pg.84]    [Pg.566]    [Pg.305]    [Pg.309]    [Pg.227]    [Pg.130]    [Pg.155]   
See also in sourсe #XX -- [ Pg.73 ]




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