As a Standard Reference Database (SRD), REFPROP 10 is commercial software.
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Downloading REFPROP from torrent sites, cracked versions, or unauthorized sources is: Refprop 10 Download
You can purchase and download the full REFPROP 10 database directly from the NIST Standard Reference Data (SRD) website . As a Standard Reference Database (SRD), REFPROP 10
Given the surge in interest in supercritical CO2 cycles and carbon capture, REFPROP 10 offers significantly improved viscosity and thermal conductivity data for CO2. As a Standard Reference Database (SRD)
The full version of REFPROP 10.0 is available directly from the NIST Store .