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V I Zvalinskiĭ

Publications and source records attributed to V I Zvalinskiĭ.

8 recordsLinked to original sources
PubMedDate not supplied

[Postluminescence of the marine green alga Ulva fenestrata in millisecond and decisecond attenuation intervals].

Excitation and radiation spectra of the stationary level of postluminescence of marine green alga tallom were measured in millisecond and decisecond attenuation intervals. On the basis of these data and of temperature and light relationships of postluminescence the conclusion is drawn concerning the existence of three independent pigment systems within the range of Photosystem-2, which are responsible for luminescence generation within the given limits of attenuation.

Chlorophyta↗
PubMedDate not supplied

[Analysis of photosynthesis light curves under continuous illumination].

A mathematical description of the photosynthesis light curve is proposed taking into account the type of photosynthetic unit (PSU) organization (unicentral or multicentral), energy migration between the PSU, and the nonlinear character of the dark process limiting the rate. In the case of unicentral PSU the light curve is described by the expression: I = v (1--yv)/(1--v) where I is light intensity; v is relative rate of photosynthesis (relative to the maximal rate); y is the parameter which determines the shape of the curve. Its value depends on the efficiency of energy migration between PSU and on the ratio of the limiting dark reactions rates. The variations of the value from 1 to 0 give different known types of light curves. Coordinates are proposed in which the curves for multicentral and unicentral PSU are distinguished and parameter is estimated. Experimental light curves for a number of marine algae correspond to the supposition of the PSU unicentral organization, with y = 0.9.

Darkness↗
PubMedDate not supplied

[Photosynthesis light curves under flash illumination].

Light curve of the multicentral model of photosynthetic unit (PSU) has been obtained. The shape of the curve depends on the efficiency of energy migration between PSU--for the unicentral PSU, and on the number of traps for multicentral PSU. The criteria distinguishing between the two models are proposed. If the efficiency of energy migration between PSU is no more than 0,7, then, there exist ony unicentral and bicentral PSU.

Kinetics↗
PubMedDate not supplied

[Effectiveness of excitation energy migration in the phycobilisomes of red marine macroalgae].

Phycobilisomes (PBS) were isolated from talloms of sea red macroalgae: annual Gloiopeltis furcata from illuminated and shaded shoal and perennial Ahnfeltia tobuchiensis. The spectral changes have shown that R-phycoerythrin, phycocyanin, allophycocyanin, allophycocyanin B were contained in PBS of the algae under study. The efficiency of energy migration to the ultimate acceptor-allophycocyanin B is twice as low in Ahnfeltia tobuchiensis (0.41) as in that of Gloiopeltis furcata, which may be due to the difference in the tallom age. Greater efficiency of excitation energy transfer from phycoerythrin to phycocyanin (0.93), from phycocyanin to allophycocyanin (0.98), from the latter to allophycocyanin B (0.96), as well as from phycoerythrin to allophycocyanin B (0.89) in PBS of shaded G. furcata combined with a relatively higher content of R-phycoerythrin, seems to be the result of algae adaptation to low illumination conditions.

Energy Transfer↗
PubMedDate not supplied

[Nature of the afterglow of marine algae].

Excitation spectra and light curves were studied in three species of marine algae at monochromatic light excitation of the second-range afterglow. It was shown that light curves were satisfactorily described by an equation similar to the equation of enzyme catalysis with low light intensity of half-saturation (about 0.5 W X m-2). Shapes of the excitation spectra and spectral curves of quantum yield of the second-range afterglow was analysed considering the early non-linearity of its light curves. It was found that the results obtained and the literature data on a relatively high quantum yield of the second-range afterglow in the region of absorption of long-wave pigment system (above 680 nm) can be explained by the non-linearity mentioned above, not suggesting a participation of PSI in the generation of this afterglow.

Chlorophyta↗