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Start Over Coverage 629-643

1. Essential norm and a new characterization of weighted composition operators from weighted Bergman spaces and Hardy spaces into the Bloch space

Creator:
Li, Songxiao, Qian, Ruishen, and Zhou, Jizhen
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, mathematics, Bloch space, weighted Bergman space, essential norm, weighted composition operator, 13, and 51
Language:
English
Description:
In this paper, we give some estimates for the essential norm and a new characterization for the boundedness and compactness of weighted composition operators from weighted Bergman spaces and Hardy spaces to the Bloch space., Songxiao Li, Ruishen Qian, Jizhen Zhou., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Evaluation of relative contribution of initial and variable chlorophyll fluorescence measured at different temperatures

Creator:
Goltsev, V., Yordanov, I., and Tsonev, T.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
The temperature dependence of the induction kinetics parameters of chiorophyll (Chl) fluorescence in leaves and isolated chloroplasts of young plants of PhaseoliLt vulgaris L. was studied. Theoretical prerequisites for the influence of fluorescence measuring temperature as well as 3 min pretreatment of leaf discs cn both the photophysical and dark processes in the photosynthetic appaiatus were evaluated. The registration manner of fluorescence kinetics detennined the pattem of temperature dependence curve. The characteristic temperature of sharp changes of induction kinetics parameters, maximal and initial fluorescence and Fq, were in ranges of 45-47 and 55-60 °C, respectively. The fitting of experimental data from thermograms registered at weak exciting iiradiance in thermoinactivated leaf discs allowed to estimate the activation energy (FJ of the intemal energy conversion process in excited Chl molecule as 51.2±0.15 kJ moTT The theoretical analysis of /'q measured by a PAM fluorometer showed that Fq registered even at low inadiances markedly exceeded its ideál dark value. The Fq measured at 25 °C was increased by 125±5.3 % by the herbicide DCMU and diminished by -23.8±1.6 % by the elechon acceptor DCBQ. At the experimental conditions ušed there were about 25 % of 1\ from dosed Qg non-reducing reaction centres in the measured Fq value. Thus the thermoinduced increase in Fq observed within the temperature inteiwal of 45-50 °C might be doně by a transition of PS2 reaction centres from a statě capable of reducing Q3 to a Qg-non-reducing statě.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public