PET	Polyethylene terephthalate
V	The volume of the specimen [m3]
ma	The mass of the specimen in air [kg]
mst	The apparent mass of the immersed stirrup [kg]
mw	The apparent mass of the immersed specimen [kg]
ρw	The density of water, at 20 °C [kg/m3]
ρc	The density of the specimen [kg/m3]
m	The mass of the specimen [kg]
td	The diffusive time of the sample
e	The sample thickness [m]
a	Thermal diffusivity [m2/s]
b	Thermal effusivity [Jm−2K−1s−0.5]
k	Thermal conductivity [W/mK]
Cp	Thermal capacity [J/kgK]
x	The ratio of the sample