Microstructural analysis was carried out on a copolymer of vinyl alcohol and a small amount of crotonic acid. ' H NMR spectroscopy at 90 MHz and 13C NMR spectroscopy at 125.76 MHz were used to examine the various kinds of y-lactone structures formed in the copolymer. The 13C NMR spectra were useful for the trace characterization of irregular structures, e.g., 1,2-glycol linkages and short branches, in the poly(viny1 alcohol) sequence.
In the form of a crossed grating element (CGE) a novel beam splitter was fabricated by using a pair of holographic surface relief gratings with high spatial frequencies dually formed on a substrate plane. The CGE which acts as a beam splitter as well as a polarized beam splitter was experimentally assembled into a magnetooptical pickup head followed by investigation of optical properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.