Showing papers by "Münster University of Applied Sciences published in 1997"
TL;DR: In this article, a refrigerant blend containing R143a and R125 (50 50% by weight) has been experimentally measured and mathematically correlated for low and medium temperature applications.
Abstract: For a blend containing R143a and R125 ( 50 50% by weight), thermodynamic data like vapour pressures, liquid densities, as well as the volumetric behaviour of the gaseous phase, have been experimentally measured and mathematically correlated. This refrigerant blend shows azeotropic behaviour and is known as R507 according to the ASHRAE nomenclature. For use in refrigeration and air-conditioning units in low and medium temperature applications, R507 is a suitable refrigerant. Test results based on measurements from a refrigeration installation have shown that similar operating parameters can be achieved in comparison to R502. The compressor discharge temperatures, pressure ratios and coefficients of performance compare well to the traditionally used azeotropic refrigerant R502. Further, the tests have shown that on average the refrigerating capacities of R507 are approximately 5–6% higher than the capacities of R502.
18 citations
TL;DR: In this paper, DTA and XRD measurements were carried out with reactive precursors taken from the YO1.5-BaO-CuO system in order to investigate mechanisms of YBa2Cu3O7−x formation.
Abstract: DTA and XRD measurements were carried out with reactive precursors taken from the YO1.5-BaO-CuO system in order to investigate mechanisms of YBa2Cu3O7−x formation. The reactions taking place depend strongly on phase composition, phase purity, powder size and heating rate. Among the examined reactive precursors a mixture of 7Y2O3+22BaCuO2+10CuO turned out as the most suited for melt-processing.
8 citations