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Start Over Coverage 119-127

2. Changes of the delayed fluorescence characteristics in Spirulina, Anabaena and Chlorella in response to chromatic adaptatíon and irradiance

Creator:
Znak, N.Y. and Morgun, V.N.
Format:
print
Type:
model:internalpart and TEXT
Subject:
chlorophyll, reaction centres, phycobilins, photosystem 2/ photosystem 1, photosynthetic electron transport, fluorescence induction, fluorescence emission spectra, and diuron
Language:
Multiple languages
Description:
Effíciency of the energy transformation for CO2 fixation (E), and kinetics of the initial 02-mediated electron transport of Spimlina platemis (Gom.) Geitl. and Chlorella vulgaris Beijerinck cells were measured after adaptation to various growth irradiances (7) by means of the delayed fluorescence (DF) induction curves. Maxima of the membrane potential expenses during induction period were observed at I half saturating oxygen evolution; they were shifted according to growth 1 remaining higher in Spirulina than in Chlorella. The alterations of absorbance and fluorescence spectra at 25 oC after adaptation to / demonstrated changes in composition of pigments of algae, created to compensate for the imbalance in radiation absorption between the two photosystems. For Spirulina cells, the value of E was higher after growing under low /, or under blue radiation absorbed mainly by photosystem (PS) 1 (400-500 nm) with excitation by yellow (570 nm) radiation. For Chlorella cells, it was also higher after growing under low I. Under such conditions the half-rise time for DP-phase of DF induction curve decreased, which reflected an acceleration of kinetics of the initial electron transport between photosystems. An opposite situation was observed with Spirulina cells grown under high I or yellow radiation, and Chlorella cells from high I. Enhancement of effective PS2/PS1 ratio associated with decrease of reaction centre (RC) 2/RCl stoichiometry may be a cause of the increase of E and high membrane energization under saturating I in algae adapted to low 1.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Influence of boron deficiency on 14C02 and [U-14C] saccharose incorporation in primary metabolites in relation to essential oil accumulation in Meutha piperita

Creator:
Srivastava, N.K. and Luthra, R.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Under boron (B) deficiency, the CO2 exchange rate, chloropliyll (Clil) and oil contents significantly decreased, whereas Clil alb ratio, leaf area ratio and leaf stem ratio significantly increased. When B-deficient plants had been siipplied witli tlie control solution for 3 weeks, there was a partial recoveiy in sonie growtli and yield parameters. In leaves of deficient plants, •^C02 incoiporation in sugars, ainino acids and organic acids decreased, whereas in stems the incoiporation of these three fractions was higher than in the Controls. Upon recovery (3 weeks) the pattenis of '‘*C02 incoiporation in sugars, amino acids and organic acids in leaves and stems were similar to those in conPol plants. In leaves of the B-deficient plants, [U-’‘*C] saccharose incoiporation was very high with respect to Controls, and a major portion was in ethanol soluble fraction. The incoiporation was significantly higher in sugars and organic acids than in amino acids. A substantial portion of labellcd saccharose remained in the stem and it was significantly higher than in control plants. Under B- deficiency, the levels of primaiy metabolites and their partitioiiiiig between leaf and stem significantly influenced the essential oil accumulation.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. The Saxo turbine - an interesting selection for reliable and efficient operation

Creator:
Gale, Janez, Dolenc, Damir, Bergant, Anton, and Cizelj, Sandi
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
vertical axial water turbine, Saxo turbine, operation feedback, medium size HPP, and double-regulated turbine
Language:
English
Description:
Double-regulated vertical axial water turbine with conical distributor, which is worldwide known as a Saxo-type turbine, is the main subject of this paper. Due to continuous research, development and improvement, advance and compact structure, simplified civil construction works, reliability, ecological design and versatile applicability, the turbine became very recognizable product of company Litostroj Power, with over 30 successfully commissioned units in North American and Canadian market mainly. Authors see the Saxo turbine as one of the most interesting and suitable solutions for small and medium size hydro power plants. This paper aims to draw attention on this unique and interesting turbine design especially because experiences show that hydro power plant investors are somehow conservative and they mainly prefer and trust in more conventional turbine types i.e. Kaplan turbines and tubular turbines. The paper enlightens important design, hydraulic, economic and operation advantages of the Saxo-type turbines and points out most obvious advantages comparing to tubular and Kaplan type turbines. As an evidence of safe and reliable operation, there is a special section at the end of the paper which is focused on field-feedback experiences obtained during exptensive turbine testing at commissioning tests, final field performance acceptance tests and operation experiences. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Validation of friction factor predictions in vertical slurry flows with coarse particles

Creator:
Bartosik, Artur
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
flow with coarse particles, particle-wall stress, and modelling of vertical flow
Language:
Slovak
Description:
The paper presents validation of a mathematical model describing the friction factor by comparing the predicted and measured results in a broad range of solid concentrations and mean particle diameters. Three different types of solids, surrounded by water as a carrier liquid, namely Canasphere, PVC, and Sand were used with solids density from 1045 to 2650 kg/m3, and in the range of solid concentrations by volume from 0.10 to 0.45. All solid particles were narrowly sized with mean particle diameters between 1.5 and 3.4 mm. It is presented that the model predicts the friction factor fairly well. The paper demonstrates that solid particle diameter plays a crucial role for the friction factor in a vertical slurry flow with coarse solid particles. The mathematical model is discussed in reference to damping of turbulence in such flows. As the friction factor is below the friction for water it is concluded that it is possible that the effect of damping of turbulence is included in the KB function, which depends on the Reynolds number.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public