Theoretical study of a melting curve for tin
The melting curve of Sn has been calculated using the dislocation-mediated melting model with the 'zone-linking method'. The results are in good agreement with the experimental data. According to our calculation, the melting temperature of γ-Sn at zero pressure is about 436 K obtained by the extrapolation of the method from the triple point of Sn. The results show that this calculation method is better than other theoretical methods for predicting the melting curve of polymorphic material Sn.
A sampling cone 3 and/or a cone gas cone 4 and/or an extraction cone 8 of a mass spectrometer are disclosed having a metallic carbide surface or coating. The metallic carbide surface or coating may comprise a transition metal carbide, a carbide alloy, or a mixed metal carbide alloy, but preferably comprises titanium carbide. The coated surface is intended to reduce adsorption of material on contact with the surface of the sampling or extraction cone.