In order to investigate the feasibility and practicability of a zeotropic HFC refrigerant blend of R404A (R125/R143a/R134a, 44/52/4Wt%) as a substitute for R22, the LSLG16 open-type screw water chiller originally designed for R22 was charged with R404A and its performance experiments were carried out under different operating conditions.
In order to investigate the feasibility and practicability of a zeotropic HFC refrigerant blend of R404A(R125/R143a/R134a,44/52/4wt%) as an alternative to R22,the YCLG16 open-type screw glycol Chiller originally designed for R22 was partially modified and then charged with R404A. The performance experiments of the screw glycol Chiller were conducted under different operating conditions.
A polyamic acid (PAA)/polyurethane (PU) blend with PU as the disperse phase was first prepared via in situ polymerization of pyromellitic dianhydride and 4,4-oxydianiline in PU solutions.
They came from Arctic-Tertiary, Paleo-tropical-Tertiary and Tethys-Tertiary florisitic elements, and the blend of the three elements with many genera of autochthonous origin.
The surface composition of the blend films was determined by Fourier transform infra-red spectroscopy coupled with a variable incidence angle attenuated total reflection accessory (ATR-FTIR).