Compressibility calculated values

Thermal Properties at Low Temperatures For sohds, the Debye model developed with the aid of statistical mechanics and quantum theoiy gives a satisfactoiy representation of the specific heat with temperature. Procedures for calculating values of d, ihe Debye characteristic temperature, using either elastic constants, the compressibility, the melting point, or the temperature dependence of the expansion coefficient are outlined by Barron (Cryogenic Systems, 2d ed., Oxford University Press, 1985, pp 24-29). 

Use the critical constants for hydrogen given in Table 5.3 to calculate the parameters a and b for the van der Waals and Redlich-Kwong equations for hydrogen. Use each of these equations to calculate the compressibility factor z for hydrogen as a function of l/Vm at 50 K between 0.1 Mpa and 20 MP, and compare your calculated values with the experimental values of Johnston and White [16]. 

The thiocyanate salt of the TTF radical cations exists as dark-purple needlelike crystals that are insoluble in nonpolar solvents and moderately soluble in warm polar solvents (e.g., acetonitrile, dichloromethane). Stoichiometries derived from elemental analysis for this and most salts of the TTF radical cations are not unequivocal since several calculated values come within the acceptable limits (i.e., 0.3% per element) of the percentages actually determined. For identification purposes we have called the thiocyanate (TTF)14(NCS)8, although, for example, (TTF) (NCS)6, (TTF)I2(NCS)7, and (TTF)ls(NCS)8 are also consistent with our results. The compressed pellet resistance is 2-6 ohms (see Table I). 

Figures 8.2a-c show the calculated values of the Storage to Initial Ratio of crushing strength after storage for 8 weeks (SIR(S)), for the tablets prepared with 157, 314 and 472 MPa compression load levels, respectively.

Since the activation energy for ionic recombination is mainly due to viscosity we use the activation energy for viscous flow (10kJ.mol l). AH ] and 3 were determined from conductance as 44.2kJ.mol and 11,4kJ.mol From the data presented in Table III it is clear that the temperature dependence of the slope is very satisfactorily described by A% +l/2(AHd-AH3). Another, and rather critical, test for the applicability of eq. 14b is the effect of pressure since the slope of eq. 14b is largely pressure independent so that we ask here for a compensation of rather large effects. From Table III we Indeed see an excellent accordance between the experimental value and the pressure-dependence calculated from the activation volume of viscous flow (+20.3 ctPmol ), AVd (-57.3 cnAnol" ) and (-13.9 cnAnol ) the difference between the small experimental and calculated values is entirely with the uncertainties of compressibility - corrections and experimental errors. 

Pseudoreduced compressibility is a function of z-factor and pseudore-duced pressure. Thus, a graph relating z-factor to pseudoreduced pressure, Figure 3-7, Figure 3-8, or Figure 3-9, can be used with Equation 6-14 to calculate values of Cpr. 

The ultimate pressure of a Roots blower/backing pump combination is approximately that of the backing pump divided by the compression ratio (k0) for the Roots pump at this pressure. In practice, however, the calculated value should be multiplied by a factor of 4 to 5 to take into account performance deficiencies of the backing pump. 

Calculated values of In and In result from evaluation of the integrals for various and Pr from the compressibility-factor data of Figs. 3.12 through 3.15, and we may plot these quantities vs. Pr for selected values of T,. We also have the option of plotting and rather than their logarithms. Equation... 

Landshoff made two calculations of the lattice energy of NaCl, the first with wave fimctions in which the exchange of electrons within the ion was neglected, the second with Hartree-Foch wave functions in which this exchange was taken into account. He calculated the lattice energy, the lattice parameter, and the compressibility. The values he obtained are listed in Table XI and compared with the experimental ones. He treated a set of linear combinations of the wave fimctions of the free ions as though they were exactly orthogonalized and normalized but in... 

Figure 5 shows the temperature dependence of the surface tension. The differences between calculated values and the experimental ones do not exceed ca. 1 mN m-1. An adjustable parameter is not used by assuming that the k does not vary with the temperature and is fixed at 0.5, a theoretical value for both PS and PVME. This indicates that the simulated equation-of-state parameters for the component polymers are reasonable. It has been known that the LCST behaviors are originated from the specific interactions between components and/or the finite compressibility of mixture and that the phase separation is entropically... 

---