Results 291 to 300 of about 304,325 (345)

Period four oscillations in chlorophyll a fluorescence

Photosynthesis Research, 2002
The discovery of period four oscillations of the fluorescence yield under flashing light demonstrated that not only the redox state of the Photosystem II (PS II) electron acceptor Q(A), but also the oxygen evolving cycle (described by the S states) modulates the fluorescence yield of chlorophyll (Chl). The positive charges accumulated on the donor side
René, Delosme, Pierre, Joliot
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A non-fluorescent complex of chlorophyll a with plastocyanin

Biochemical and Biophysical Research Communications, 1985
A complex between chlorophyll a and plastocyanin has been prepared by dialysis of mixtures of chlorophyll in Triton X-100 micellar solution with the protein. The complex appears to contain no more than one chlorophyll per plastocyanin molecule, and is non-fluorescent, whether the protein is in the oxidized or reduced state.
R C, Davis, R R, Knotts, G R, Seely, E R, Shaw   +3 more
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In vivo analysis of chlorophyll a fluorescence induction

Photosynthesis Research, 2008
Quantitative characteristics of photosynthetic electron transport were evaluated in vivo on the basis of the multi-exponential analysis of OJIP fluorescence transients induced by saturating actinic light. The OJIP fluorescence curve F(t), measured in Chlamydomonas reinhardtii cells, was transformed into the (1 - F(O)/F(t)) x (F(V)/F(M))(-1) transient ...
T, Antal, A, Rubin
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Lifetime of the long-wavelength chlorophyll fluorescence

Biochimica et Biophysica Acta, 1963
The fluorescence lifetime of chlorophyll in vivo and in vitro was measured with a phase fluorimeter. The lifetime in vivo of the long-wavelength emission (730 mμ) which appears at low temperature was 3.1 mμsec. It is concluded that this emission is fluorescence rather than phosphorescence as had been previously reported by Brody.
W L, BUTLER, K H, NORRIS
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Picosecond fluorescent kinetics of in vivo chlorophyll

Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1973
Abstract Fluorescent emission kinetics at 685 nm of in vivo escarole chloroplast chlorophyll has been studied on a picosecond time scale using a frequency-doubled, mode-locked Nd: glass laser (4-ps wide pulses) and an optical Kerr gate. The fluorescent risetime is less than 10 ps and the decay time of the fluorescence envelope is 320 ± 50 ps.
SEIBERT M, ALFANO, Roberto, SHAPIRO SL
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Fluorescence of chlorophyll a in EPA

Chemical Physics Letters, 1976
Abstract New results are reported from the fluorescence spectra of chlorophyll a in EPA. The new spectra are obtained for purer samples than hitherto. Previously reported hot band emission is shown to be due to impurities, and the supposed dimer fluorescence to self-absorption.
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pH control of the chlorophyll a fluorescence in algae

Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1971
Abstract The pH of the suspension medium was found to have a remarkable influence on the “slow” (min) time course of Chlorophyll a fluorescence yield in the green alga Chlorella pyrenoidosa and in the blue-green alga Anacystis nidulans . In Chlorella, the decay of fluorescence yield, in the 1- to 5-min region, is strongly retarded at alkaline pH;
G, Papageorgiou, , Govindjee
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Chlorophyll a fluorescence illuminates a path connecting plant molecular biology to Earth-system science

Nature Plants, 2021
A. Porcar-Castell, Z. Malenovský, T. Magney, Shari Van Wittenberghe, B. Fernández-Marín, F. Maignan, Yongguang Zhang, K. Maseyk, J. Atherton, L. Albert, T. Robson, F. Zhao, J. García-Plazaola, I. Ensminger, P. Rajewicz, Steffen Grebe, M. Tikkanen, J. Kellner, J. Ihalainen, U. Rascher, B. Logan   +20 more
semanticscholar   +1 more source

Concentration Quenching of Fluorescence in Chlorophyll Solutions

Nature, 1948
IN a paper concerned chiefly with the results of measurements of the self-quenching of the fluorescence of solutions of aromatic hydrocarbons1, Weiss and Weil-Malherbe report a few measurements on the self-quenching of ethyl chlorophyllide solutions.
W F, WATSON, R, LIVINGSTON
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Intensity effects on the fluorescence of in vivo chlorophyll

Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1977
A technique for measuring relative quantum yields of fluorescence with a picosecond streak camera is described. We show that Chlorella pyrenoidosa exhibit an intensity dependent quantum yield when irradiated with single picosecond light pulses. This effect also occurs under conditions that inhibit the activity of the reaction centres, which can ...
G, Porter, J A, Synowiec, C J, Tredwell
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