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A new simplified form of an equation of state suitable for the correlation of pVT-data is presented. The new equation of state is capable to model pVT-data in the low- and high-pressure regions as well as in the critical region. Taking a fugacity approach as a basis, we have calculated the solubility of several low-volatile solid organic compounds, in particular of the globular molecule adamantane in CO2 and the natural dyestuff β-carotene in three compressed gases, i.e. CO2, CClF3, and N2O. For all systems except β-carotene+N2O solubility data measured up to 100 MPa and more (180 MPa for β-carotene+CO2 and+CClF3) are available. Experimental results for the systems β-carotene+CO2 and+CClF3 are also reported. Here, adamantane serves as an example for a relatively high-soluble substance, while β-carotene represents low-soluble solutes. Solubility maxima, which have been found experimentally as a function of pressure or density at constant temperature, are considered in the correlations. [Copyright &y& Elsevier]

Abstract: Upon heating or isotropic expansion, condensed matters (solids and liquids) can reach their stability limits, where the system must be stabilized by the appearance of a second phase. During isotropic expansion, the pressure can reach negative values. In auxetic materials, volume expansion is an inherent way of behavior, therefore, negative-pressure states can be reached easily during uni-axial stretch. In this paper, a comparison of various stability limits of pure and ordered one-component stretched solids will be mapped, with special focus on auxetic materials. [Copyright &y& Elsevier]