Device degradation

The solutions in the region inside the spinodal domain are unstable, whereas the solid solutions in the region between the binodal and spinodal lines are metastable. The presence of a miscibility gap limits the potential usefulness of these materials in device applications. Solutions with compositions lying inside the spinodal domain cannot be grown by LPE, whereas metastable solid solutions have a tendency toward phase separation and, eventually, device degradation. 

Selection of Tests for Interactions with Blood Tests for Cytotoxicity - In Vitro Methods Tests for Local Effects after Implantation Ethylene Oxide Sterilization Residuals Clinical Investigation of Medical Devices Degradation of Materials Related to Biological Testing... 

A common mode of device degradation in polyfluorene-type PLEDs is the formation of keto defects during device operation and the related change of the emission spectrum with a broad peak emerging around 2.3 eV (Fig. 7). 

Pattern of half-life was similar to that of initial phase, but there must be another factor that could affect life-time. There are some assumed mechanisms for luminance decrease or device degradation [31],[32]. For example, degra- dation of the interface between deposited layers, shift of exdton recombination zone from emitting layer, intrinsically weak chemical bond of used materials and there must be a lot of possible degradation mechanism we could not conceive. 

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