Qualitative classification of mulchers

ArticleMulchers are helpful in forest establishment and tending. Numerous mulchers are available, so buyers can become disoriented when choosing one. This paper was aimed at creating a classification of mulchers based on the evaluation of the most important parameters: weight, required engine performance, and mulching diameter. Through ANOVA, and regression and correlation analyses of our database, we created six machine classes, devised their upper limits, and assigned mulchers to the classes. Class K1 (weight up to 1,300 kilograms; performance up to 75 kilowatts; mulching diameter up to 22 centimetres) was the most popular one with 88 mulchers. It was followed by class K2 (1,800 kilograms; 100 kilowatts; 27 centimetres) with 61 mulchers, class K4 (3,200 kilograms; 175 kilowatts; 41 centimetres) with 44 mulchers, class K3 (2,300 kilograms; 125 kilowatts; 31 centimetres) with 34 mulchers, class K5 (4,100 kilograms; 225 kilowatts; 51 centimetres) with 18 mulchers, and class K6 (no upper limit) with nine mulchers

Laser modification of graphene oxide layers

The effect of linearly polarized laser irradiation with various energy densities was successfully used for reduction of graphene oxide (GO). The ion beam analytical methods (RBS, ERDA) were used to follow the elemental composition which is expected as the consequence of GO reduction. The chemical composition analysis was accompanied by structural study showing changed functionalities in the irradiated GO foils using spectroscopy techniques including XPS, FTIR and Raman spectroscopy. The AFM was employed to identify the surface morphology and electric properties evolution were subsequently studied using standard two point method measurement. The used analytical methods report on reduction of irradiated graphene oxide on the surface and the decrease of surface resistivity as a growing function of the laser beam energy density

Novel approach for manufacture of single-grain EuBCO/Ag bulk superconductors via modified single-direction melt growth

AbstractDespite the success of top‐seeded melt growth (TSMG) and TSIG, some key aspects of their manufacture need to be addressed including the presence of microstructural defects, inhomogeneities in trapped field and the difficulty of growing large‐diameter bulk monoliths. Recently, a promising new method single‐direction melt growth (SDMG) appears to address the majority of the shortcomings of TSMG and TSIG. Single‐grain EuBCO/Ag bulk with the highest peritectic temperature to date was grown by modified SDMG. This remarkable achievement was made possible by lowering the peritectic temperature of the precursor composition by the addition of silver and by using single‐grain EuBCO fabricated by TSMG as a seed. The EuBCO/Ag bulk grown by SDMG has demonstrated significant improvements in comparison to a reference TSMG sample. A reduction of approximately 30% in defect area (associated primarily with porosity), as well as a significantly enhanced homogeneity of trapped field and critical temperature, was observed. Furthermore, the critical current density curves exhibit a considerable improvement, particularly in the 2–5 T field range. The SDMG technique has considerable potential for scale‐up for the fabrication of large‐diameter bulk single grains, with only growth along the c‐axis involved during the thermal process.</jats:p

Zvýšení podílu přírodě blízké porostní složky ekosystému lesa velkoplošných chráněných území

V rámci řešení projektu byl zpracován souhrn metodik pro řešení - význam tlejícího dřeva pro přirozenou obnovu lesa, problematika managementu dřeva, dekompozice tlejícího dřeva a biomasy obecně pro bilanci a koloběh živin, formulace strategií managementu. Metodiky jsou doplněny literární rešerší. Dále byl vytipován soubor ploch v cíleném stavu pro vzorový bezzásahový režim hospodaření a pro ně byly zpracovány základní popisné charakteristiky. Pro soubor ploch na území NP Šumava bylo realizováno vzorové šetření, stanovení porostních charakteristik vymezené pokusné plochy včetně simulace růstovým simulátorem SILVA 2.2. Obdobné šetření bylo realizováno v oblasti Krkonošského národního parku