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Optical properties of three types of terthiophene (3T) functionalized conjugated triarm (star-shaped) polymers consisting of poly(9,9-di-n-octyl-fluorene-2,7-vinylene) (PFV) arms and different [2,4,6-tri(biphenyl)benzene (TBP), 1,3,5-tri(benzyl)benzene (TBB), and triphenylamine (TPA)] cores, prepared by combined olefin metathesis with Wittig coupling, have been studied. Relative intensities [increases in the higher vibronic bands, (0, 1) fluorescence (FL)] of the fully conjugated TPA-core polymers, TPA(PFV-3T)3, in the fluorescence (FL) spectra in tetrahydrofuran (toluene) solution were higher than those in the other triarm polymers, TBP(PFV-3T)3, TBB(PFV-3T)3, whereas no significant differences were observed in their UV-vis spectra; notable temperature dependences were not observed in the UV-vis and FL spectra (at -5, 25, and 55 °C). Remarkable differences were not observed in the spectra in these polymer thin films, whereas λmax values red-shifted due to the formation of J-type aggregates. The observation for the time-resolved study well corresponds to results for the steady-state fluorescence measurements. The observed unique emission by the star-shaped (triarm) polymer containing the TPA core would be assumed to be due to a difference in nature of the core (higher coplanarity) compared to that of the others. © 2018 American Chemical Society., info:eu-repo/semantics/published

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info:eu-repo/semantics/published

In Minamata Bay, sediment containing mercury higher than 25 ppm has accumulated on the bottom, and dredging work continues. The dredging has been conducted carefully, and secondary pollution as a result of disturbance of the bottom sediment has been prevented. The mercury concentration in fishes was investigated to determine 'the conditions before dredging. As a result, a good correlation between the mercury concentration in fishes and the body length was found. Six kinds of fishes were chosen for monitoring. These were selected because they were present in sufficient numbers, the mercury concentration in them was adequate, and there was good correlation between mercury concentration and body length. The monitoring work has been successful, based on the results obtained., This article is from 'Management of Bottom Sediments Containing Toxic Substances: Proceedings of the U.S./Japan Experts Meeting (13th) Held in Baltimore, Maryland on 3-5 November 1987,' AD-A253 003, p1-22.

Acrylamide polymer is widely used as a coagulant for the treatment of industrial wastewater, domestic sewage, sludge, and reclamation and dredging effluent. The polymer includes 0.01% of acrylamide monomer, a well known neurotoxin. An analytical method for determination of acrylamide method for determination of acrylamide monomer in carp was investigated. The rate of accumulation of acrylamide monomer in fish was slow and reached about 0.8 times the concentration in the rearing water (10 ppm) at day 40. The accumulation of acrylamide monomer in fish from polymer was nondetectable. Therefore, it is concluded that the use of acrylamide polymer as a coagulant may not cause serious problems for human health., This article is from 'Management of Bottom Sediments Containing Toxic Substances, Proceedings of the U.S./Japan Experts Meeting (8th) Held at Tokyo, Japan on 8-10 November 1982,' AD-A149 291, p147-166.