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SynopsisInteraction between poly(riboadenylic acid) (poly (A)) and Cu2+ in neutral aqueous (D20) solution has been studied by 'H, 31P, and 13C nuclear magnetic resonance. Electron-nuclear hyperfine coupling constants and apparent electron-nuclear distances were determined by measurement of TI and T, values as a function of temperature. The apparent distance fTom Cu2+ to H(2), H(8), H(l'), and phosphorus nuclei were estimated to be 4.1, 3.7, 5.1, and 3.1 A from these results. Cu2+ was found to coordinate directly to the phosphate groups of poly(A) (Type I complex). Simultaneously there are bindings of Cu2+ directly to one of the nitrogen atoms of adenine ring, mainly to N(7) (Type I1 complex) and either N(l) or N(3) (Type 111 complex).

The difference spectrum between copper chlorophyllin (Cu-chln) plus poly(vinyl alcohol) (PVA) and Cu-chln alone exhibits a maximum at 652 nm in water. The Benesi-Hildebrand plots give equilibrium constants of 833 mol−1 dm3 for UMR-20H (degree of saponification: 81.7%) and 1820 mol−1 dm3 for UMR-20M (degree of saponification: 63.8%). The Scatchard plot of these data shows the existence of a cooperative binding.

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SynopsisThe polymerization mechanism of methyl methacrylate (MMA) with flavin mononucleotide (FMN) and cerium nitrate was investigated. The effect of the polymer grafted to FMN on the color fastness to light of some dyes were also investigated. Poly(methy1 methacrylate) (PMMA) was produced with FMN, cerium nitrate, and MMA in the presence of water above 40°C. The conversion of PMMA is proportional to the reaction time up to 2 h in this system. It is also proportional to the first order of concentration of FMN and Ce(1V). Activation energy of the polymerization reaction was estimated to be 29.3 kJ mol-' by the investigation of the temperature dependence of conversion. Purified polymer in acetone has the absorption peak at the same wavelength as FMN aqueous solution. The color fastness to light of Methylene Blue and anthraquinone dye were improved in the presence of the obtained polymer. Heat stability of the printed image which is made by transferring anthraquinone dye did not decrease by use of obtained polymer to recording layer of the medium in dye transfer printing system.