Synthetic fluid inclusion technique

Xhis technique, in which small amounts of fluid are trapped by healing fractures in quartz, has been used by Sterner and Bodnar (1984) for studying pVXx properties of aqueous electrolytes (CaCl2, KCl, NaCl) and aqueous CO2 at supercritical temperatures up to 820 C (Knight and Bodnar, 1989), and extended by Frost and Wood (1997) up to 1400 °C. 

Xhe experimental procedure to produce synthetic fluid inclusions uses quartz cores approximately 4 mm in diameter and 1-2 cm in length, which are fractured by thermal-shock technique at 350°C. Xhe cleaned and dried cores are placed into platinum capsules along with the fluid sample, sealed with and arc-welder and placed into cold-sealed pressure vessels and taken rapidly to the desired temperature. After quenching the quartz cores were cut into 1 mm thick disks, polished, and homogenization temperatures of the inclusions were determined ( 2 C) on a microscope heating stage. 

It is assumed that fluid inclusions represent isochoric systems, and consequently the specific volume of the fluid 

Many of the theories and models described in this section were developed for the excess thermodynamic properties of solutions, including not only the excess partial molar volume, but also other excess properties. In the following subsections we have restricted the discussion to the volumetric properties of aqueous systems. 

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