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Species palatability, life history traits and litter decomposition rate
PÁLKOVÁ, Kateřina
Palatability of 20 meadow plant species was assessed in the slug grazing experiment conducted. Monocots exhibited significantly lower palatability than dicots. Litter decomposition rate was assessed in the field litter-bag test. Linear regression analysis was performed to answer the main question whether species palatability is related to litter decomposition rate and whether it is determined by the carbon or nitrogen content. Phylogenetically independent contrasts were used to eliminate correlated phylogeny effect. Regression trees were used to detect the effect of species traits on species palatability and litter decomposition rate.
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Carbon nanotubes - material for carbon paste electrodes, possibilities of preparation and characterization
Mikysek, T. ; Stočes, M. ; Švancara, I. ; Ludvík, Jiří
In this article, some new approaches to characterize the carbon paste mixtures and the respective carbon nanotube paste electrodes (CNTPEs) are presented, discussed. Particular attention has been paid to the changes of the ohmic resistance, relative to the dependence on composition of the CNTPE, the materials used, the time. Four types of carbon nanotube pastes were examined, and for the interpretation of experimental data. Some problems connected with homogeneity and stability of carbon pastes, their storage, or eventual aging effects are also discussed.
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Diffusion of C and Mn in steel weldment Fe-0.3C-5Mn/Fe-0.3C-15Mn
Král, Lubomír ; Million, Bořivoj ; Čermák, Jiří
In this paper, the results of measurements of chemical diffusion of Mn and C in weldments of alloys Fe-0,3%C-5%Mn / Fe-0,3%C-15%Mn are reported. Alloys were cast in induction furnace under protective Ar atmosphere. They were hot-forged to rods of diameter 15mm and cut into pieces of 4mm thickness. These cylindrical samples were metalographical polished. Diffusion couples, welded by electrical impulse, were sealed together with Ti-chips, into evacuated silica ampoules. After that, they were annealed at 1100-800 °C for 1.5-96 hours respectively. Measurement of C redistribution was done in a normal direction to welding interface using electron-scanning microscope Philips SEM-505WDS equipped with Microspec WDX-2A. Diffusion coefficients of C and Mn were obtained and the relations between them were found.
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