laser, 822 laser beam ionization, 822 laser dye, 822 laser ionization in mass spectrometry , 823 laser micro emission spectroscopy (LAMES) , 823 laser micro mass spectrometry (LAMMS), 823 laser Raman microanalysis (LRMA), 823 laser-jet photochemical technique, 823 lasing, 824 latent image, 824 latent period (latency) in medicinal chemistry , 824 lateral order in a polymer , 824 lateral resolution in in situ microanalysis , 824 latex, 825 lath crystal, 825 lattice distortion, 825 laws of distribution in precipitation , 825 layer, 826 layer equilibrium in chromatography , 826 leader sequence in biotechnology , 826 least motion, principle of, 827 least-squares technique, 827 leaving group, 828 lecithins, 828 lectins, 829