A light emitting diode incorporating an active emitting layer overlying a transparent substrate is provided with a reflective diffraction grating on the bottom surface of the substrate. The fitting comprises a substantially L-shaped bracket having a first flange and a second flange. The methods, processes and apparatus of the invention are useful for the synthesis of biodiesel fuels; and also useful for production of reaction products of esterification andor transesterification reactions including fatty acid alkyl esters. In a reflection mode, the plurality of spaced-apart elements function as a spectral mirror to an impinging light beam. In the image forming apparatus, the blade member in the separated state is caused to abut on an abutting toner image formed on the image bearing member.