krypton ion laser, 813 λ-transition (lambda-transition), 814 l, u, 814 l, 814 label, 814 labelling, 814 labile, 815 laboratory sample, 815 lachrymator, 815 lactams, 815 lactides, 816 lactims, 816 lactols, 817 lactones, 817 ladder chain, 817 ladder macromolecule, 817