44 research outputs found
Arbuscular mycorrhizal fungi (AMF) root colonization dynamics of Molinia caerulea (L.) Moench. in grasslands and post-industrial sites
This is an accepted manuscript of an article published by Elsevier in Ecological Engineering on 05/08/2016, available online: https://doi-org.ezproxy.wlv.ac.uk/10.1016/j.ecoleng.2016.06.029
The accepted version of the publication may differ from the final published version.The aims of this studies were: (i) to examine the influence of heavy metal content (Zn, Cd, Pb, Fe, Cu) and other physico-chemical soil parameters on the level of root colonization of Molinia caerulea and (ii) to relate root colonisation parameters and soil variables to Molinia caerulea abundance in two contrasting habitats (grasslands and heavy metal contaminated sites). The sites differ significantly in terms of bio-available heavy metal contents, particularly Zn (34 times more than grasslands), soil texture, CaCO3, organic matter (LOI%), Mg and nitrate content. Principal Component Analysis showed the strong negative correlations between frequency of mycorrhization (F), arbuscular abundance (A%) and intensity of root cortex colonisation (M%) and concentration of bio-available Zn and Cd. Moreover, no positive correlation between root colonization of Molinia and its abundance was found. The frequency of mycorrhization of root fragments (F%) was only slightly different between these two habitats, whereas the intensity of root cortex colonisation (M%) and relative arbuscular abundance (A%) were significantly lower (3 and 4 times respectively) on the post-industrial sites. The bioavailable Zn content in the substratum of post-industrial sites was strongly negatively correlated with species richness, Shannon diversity index and Evenness. In contrast, these relationships were not statistically significant in grasslands. Based on obtained results we could draw a model of possible relationships between root colonization of Molinia, HM content and Molinia abundance on grasslands and post-industrial sites. Bioavailable Zn content in the soil is a one of main factors influencing the Molinia community diversity. In the grasslands, lower amounts of bioavailable Zn, resulted in higher species richness (R) and species diversity (H) which in turn lead to higher root colonization. On the other hand, on the post-industrial sites, the elevated bioavailable Zn content strongly decreases the plant species richness (R) and species diversity (H) and this caused the decline in root colonization parameters. The low species richness on Zn-polluted sites allowed Molinia to reach higher abundance since the competition with other species is reduced
Diversity of the Schizophoria lineage (Brachiopoda: Orthida) in the Lower and Middle Devonian of Poland and adjacent areas
Ossification center of the humeral shaft in the human fetus: a CT, digital, and statistical study
Energoelektroniczne kompensatory bocznikowe jako sterowane 藕r贸d艂a mocy biernej
Na podstawie analizy rozwi膮za艅 technicznych stosowanych na 艣wiecie przedstawiono podstawowe cechy konstrukcyjne energoelektronicznych uk艂ad贸w bocznikowych. Om贸wiono wady i zalety pod k膮tem mo偶liwo艣ci wykorzystania tych uk艂ad贸w jako sterowanych 藕r贸de艂 mocy biernej w systemie elektroenergetycznym
Nowy algorytm regulacji transformator贸w zasilaj膮cych sie膰 rozdzielcz膮
W niniejszym artykule opisano przyk艂ad nowego inteligentnego algorytmu regulatora transformatora. Uk艂ad regulacji transformator贸w 110/SN, z proponowanym algorytmem dzia艂ania, umo偶liwia automatyczne dostosowanie algorytmu dzia艂ania regulator贸w do aktualnych stan贸w systemu elektroenergetycznego (np. lawina napi臋cia) i w ten spos贸b mo偶e wp艂yn膮膰 na wzrost bezpiecze艅stwa elektroenergetycznego
Laboratory large power load model. Concept, implementation, experiments
W referacie przedstawiono koncepcj臋 oraz spos贸b realizacji laboratoryjnego modelu odbioru o mocy 150 kVA. Odbiornik zaprojektowano w taki spos贸b aby umo偶liwi膰 emulacj臋 zmienno艣ci mocy dowolnego odbiorcy, jak r贸wnie偶 prac臋 transformatora zasilaj膮cego takiego odbiorc臋. W referacie zaprezentowano te偶 przyk艂adowe wyniki pr贸b eksperymentalnych potwierdzaj膮ce s艂uszno艣膰 przyj臋tej koncepcji sterowania.First section of the paper provides concept of laboratory load model basing on 150 kVA power frequency converter and Simulink Real-Time platform. Assumptions, as well as control algorithm structure is presented. Theoretical considerations based on criteria which load types may be simulated using discussed laboratory setup, are described. Implementation details are given in second section of paper. Hardware structure is presented and described. Information about used communication interface, data maintenance and storage solution, as well as used Simulink real-time features are presented. Third section describes performed laboratory tests and their results
Testing of a laboratory and simulation model of UPFC
W artykule przedstawiono koncepcj臋 oraz spos贸b realizacji laboratoryjnego modelu uk艂adu UPFC. Uk艂ad zrealizowano wed艂ug nowej metodyki oferuj膮cej elastyczno艣膰 w szerokim zakresie testowania nowych algorytm贸w sterowania. W referacie zaprezentowano te偶 przyk艂adowe wyniki pr贸b eksperymentalnych potwierdzaj膮ce s艂uszno艣膰 przyj臋tej koncepcji sterowania. Dane pomiarowe zosta艂y r贸wnie偶 wykorzystane do cel贸w walidacji opracowanego modelu UPFC.This paper presents a laboratory unit of Unified Power Flow Controller (UPFC), whose operational performance is assessed based on the results of tests carried out in commissioning phase of the project during which steady state and transient performance were mainly investigated. Measurement data were also used for validation purposes of the elaborated transient model of UPFC