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[lemma=introduce] [tag=","] [□] □
[lemma=introduce] [tag=","] [] □
Recently the use of silicon carbide and gallium nitride has permitted blue-emitting diodes to be introduced , and combining several colors in various combinations provides a mechanism to produce white light . We want to garner their support as we move to introduce , and hopefully pass , specific amendments to the law . A rigorous solution of two-dimensional light wave diffraction is introduced , and practical aspects of typical lithographic processes are addressed . A conceptual notion of " homotopy Greek letter element " is also introduced , and evidence is presented that it may be related to the root invariant . In 1927 , postgraduate instruction was introduced , and years later the department pioneered in giving postgraduate courses in the Spanish language .