Synthetic fluid inclusions in fused-silica capsules and its applications

摘要

An optical capsule, similar to a synthetic fluid inclusion, was constructed from square cross-section fused-silica capillary tubing (300 μm X 300 μm with cavity of 100 μm X 100 μm or 50 μm X 50 μm), where fluids and/or solids were enclosed under room temperature. Initially, solid, liquid, and gas samples were loaded in a tube with one end being sealed by hydrogen flame. Solid samples can be pushed into the tube by a thin steel wire, and liquid samples can be sucked into the tube by dipping the open end into the liquid after a clear section of the tube was heated and followed by centrifuging the liquid to the closed end of the tube. Gas samples can be loaded cryogenically. Normally, for a mixture, solid and/or liquid were loaded first followed by gases. After loading, the open end of the tube was sealed by hydrogen flame under vacuum (Chou et al., 2005). The optical capsule is designed for Raman spectroscopic analyses and microthermometric measurements using a heating-cooling stage. It allows studies of fluid systems under internal pressures of up to 120 MPa at 500 ℃, and much higher pressures at lower temperatures or with the application of an external pressure in a pressure vessel.