An unusual feature of the saline stratified lakes that were formed due to ongoing postglacial uplift on the White Sea coast is the presence of several differently colored thin layers in the zone with sharp gradients. ...An unusual feature of the saline stratified lakes that were formed due to ongoing postglacial uplift on the White Sea coast is the presence of several differently colored thin layers in the zone with sharp gradients. Colored layers in five lakes at various stages of separation from the sea were investigated using optical microscopy, spectrophotometry, spectrofluorimetry, and photobiology. The upper greenish colored layer located in the aerobic strata of all lakes near the compensation depth of 1% light penetration contains green algae. In the chemocline, another layer, brightly green, red or pink, is dominated by mixotrophic flagellates. Despite the very low light intensities and the presence of H 2 S, active photosynthesis by these algae appears to be occurring, as indicated by high values of the maximum quantum yield of primary photochemistry, electron transport activity, photosynthetic activity of photosystem II, the fraction of active centers, and low values of heat dissipation. In the reduced zone of the chemocline, a dense green or brown suspension of anoxygenic phototrophs(green sulfur bacteria) is located.展开更多
The first luminescence thermometer based on coordination compound of samarium and dysprosium is repo rted.High luminescence intensity and high signal resolution are reached thanks to the concentration quenching reduct...The first luminescence thermometer based on coordination compound of samarium and dysprosium is repo rted.High luminescence intensity and high signal resolution are reached thanks to the concentration quenching reduction due to the use of the trimetallic complexes of Sm-Dy-Gd.The best thermometric properties in a wide temperature range among the studied systems are demonstrated by(Sm0.2Dy0.15Gd0.65)2(tph)3(H2O)4.The sensitivity reaches 0.5%/K in visible range and 1.2%/K in NIR range at low temperatures and 0.5%/K and 0.8%/K in physiological range.展开更多
基金Supported by the RFBR(Nos.16-05-00548-a,16-05-00502-a)
文摘An unusual feature of the saline stratified lakes that were formed due to ongoing postglacial uplift on the White Sea coast is the presence of several differently colored thin layers in the zone with sharp gradients. Colored layers in five lakes at various stages of separation from the sea were investigated using optical microscopy, spectrophotometry, spectrofluorimetry, and photobiology. The upper greenish colored layer located in the aerobic strata of all lakes near the compensation depth of 1% light penetration contains green algae. In the chemocline, another layer, brightly green, red or pink, is dominated by mixotrophic flagellates. Despite the very low light intensities and the presence of H 2 S, active photosynthesis by these algae appears to be occurring, as indicated by high values of the maximum quantum yield of primary photochemistry, electron transport activity, photosynthetic activity of photosystem II, the fraction of active centers, and low values of heat dissipation. In the reduced zone of the chemocline, a dense green or brown suspension of anoxygenic phototrophs(green sulfur bacteria) is located.
基金Project supported by Russian Foundation for Basic Research(#18-33-20210)Prezident’s grant(#MK-2799.2019.3)Russian Science Foundation(#17-73-10072)。
文摘The first luminescence thermometer based on coordination compound of samarium and dysprosium is repo rted.High luminescence intensity and high signal resolution are reached thanks to the concentration quenching reduction due to the use of the trimetallic complexes of Sm-Dy-Gd.The best thermometric properties in a wide temperature range among the studied systems are demonstrated by(Sm0.2Dy0.15Gd0.65)2(tph)3(H2O)4.The sensitivity reaches 0.5%/K in visible range and 1.2%/K in NIR range at low temperatures and 0.5%/K and 0.8%/K in physiological range.
