“…One review provided a discussion of spectrophotometric methods for the determination of essential elements in milk (46), while another 0003-2700/88/0360-131R$06.50/0 © 1988 American Chemical Society considered the analysis of gases by means of ultraviolet and visible absorption (47). A number of spectrophotometric studies of various systems were reviewed and included catechol dioxygenases (48), polymers and coatings (49,50), and lignins (51).…”