National Repository of Grey Literature 9 records found  Search took 0.01 seconds. 
Sorption ability of humic acids
Pokorná, Markéta ; Havelcová, Martina (referee) ; Klučáková, Martina (advisor)
The Diploma thesis deals with humic acids and their ability to adsorb metal ions on their surface. Humic acids are aromatic polycyclic compounds which contain carboxylic and fenolic functional groups on their sidechains. Thanks to these functional groups humic acids can form complexes with metal ions of different stability and assist the partial immobilization of pollutants in the nature. In this thesis, the sorption of Pb2+ and Zn2+ ions on humic acids was studied by relatively new electroanalytic method called galvanostatic stripping chronopotentiometry. Experimental data were described by Freundlich and Langmuir isotherms. The results show that the amount of examined metal ions increases with their increasing concentration. Furthermore it was determined that Pb2+ ions are adsorbed better on humic acids than Zn2+ ions. Both metals are adsorbed better from solution containing only one metal ion than in presence of four metals at the same time (Cd, Cu, Zn and Pb) where the sorption of these metals is not influenced by the presence of other metals.
Study of Lignite Organic Matter
Doskočil, Leoš ; Maršálek, Roman (referee) ; Havelcová, Martina (referee) ; Pekař, Miloslav (advisor)
This work deals with the study of organic matter in the South Moravian lignite using the available physico-chemical methods and the results obtained are eventually considered for non-energy applications of lignite. Lignite organic matter was studied by degradation methods, which included CuO oxidation, thermochemolysis with TMAH and DFRC method. Special attention was paid to the lignite oxidation with hydrogen peroxide, which was carried out under different reaction conditions (time and temperature). Thermal degradation was performed in an inert atmosphere in order to observation of chemical change of lignite (including lignite after extraction with chloroform, demineralised lignite, remineralised lignete) during pyrolysis by means of various methods, especially TG-FTIR for analysis of gaseous products and FTIR for analysis the residual lignite after pyrolysis. Further, water-soluble fractions from lignite were characterized, particularly in terms of the content of organic substances.
Study of Lignite Organic Matter
Doskočil, Leoš ; Maršálek, Roman (referee) ; Havelcová, Martina (referee) ; Pekař, Miloslav (advisor)
This work deals with the study of organic matter in the South Moravian lignite using the available physico-chemical methods and the results obtained are eventually considered for non-energy applications of lignite. Lignite organic matter was studied by degradation methods, which included CuO oxidation, thermochemolysis with TMAH and DFRC method. Special attention was paid to the lignite oxidation with hydrogen peroxide, which was carried out under different reaction conditions (time and temperature). Thermal degradation was performed in an inert atmosphere in order to observation of chemical change of lignite (including lignite after extraction with chloroform, demineralised lignite, remineralised lignete) during pyrolysis by means of various methods, especially TG-FTIR for analysis of gaseous products and FTIR for analysis the residual lignite after pyrolysis. Further, water-soluble fractions from lignite were characterized, particularly in terms of the content of organic substances.
Sorption ability of humic acids
Pokorná, Markéta ; Havelcová, Martina (referee) ; Klučáková, Martina (advisor)
The Diploma thesis deals with humic acids and their ability to adsorb metal ions on their surface. Humic acids are aromatic polycyclic compounds which contain carboxylic and fenolic functional groups on their sidechains. Thanks to these functional groups humic acids can form complexes with metal ions of different stability and assist the partial immobilization of pollutants in the nature. In this thesis, the sorption of Pb2+ and Zn2+ ions on humic acids was studied by relatively new electroanalytic method called galvanostatic stripping chronopotentiometry. Experimental data were described by Freundlich and Langmuir isotherms. The results show that the amount of examined metal ions increases with their increasing concentration. Furthermore it was determined that Pb2+ ions are adsorbed better on humic acids than Zn2+ ions. Both metals are adsorbed better from solution containing only one metal ion than in presence of four metals at the same time (Cd, Cu, Zn and Pb) where the sorption of these metals is not influenced by the presence of other metals.
Composition and properties of organic matter in freshwater clays of the lower Cenomanian ( Peruc Mbrs ) from the slope of Litice Chlum in Zamel , East Bohemia
Martinec, Petr ; Sýkorová, Ivana ; Havelcová, Martina ; Trejtnarová, Hana ; Šulc, Alexandr ; Kubina, Lukáš
The new finding of coal bearing kaolinite claystone in the Peruc Mbr occurring at the western hillside of Litice Chlum Hill in Zamel near Potstejn has contributed to expanding our knowledge of Czech Republic‘s Lower Cenomanian sediments. The petrographic and chemical investigation was focused on elucidating the composition of the fine-grained sediment and the origin of the organic matter present therein. However, the forms of organic matter preserved in the claystones bring evidence of the existence of an overlay of plant origin of which the residues may have been carried by water and wind to the vicinity of Lower Cenomanian riverbeds. The greater abundance of inertinite macerals coupled with the presence of semicoke representing the remains of incomplete combustion occurring during wildfires also documents the occurrence of polycyclic aromatic hydrocarbons and the distribution of n-alkanes exhibiting an unusual maximum.
Fulltext: content.csg - Download fulltextDOC
Plný tet: UGN_0398222 - Download fulltextDOC
Application of geochemical analysis in the research of chemical fossils
Havelcová, Martina ; Sýkorová, Ivana ; Trejtnarová, Hana
Biomarkers (also termed chemical fossils) are specific organic compounds in geological samples which are derived from biochemical precursors by reductive or oxidative alteration processes. Chemical structures of biomarkers can be related back to the original compounds and utilized as indicators of biogenic, paleoenvironmental and geochemical processes. Examples of identified biomarkers in several studied coals, sediments, and wood fossils remnants are presented.
Pyrolysis of coal/waste plastic mixtures in cokemaking
Melegy, A. ; Sýkorová, Ivana ; Kříž, Vlastimil ; Havelcová, Martina
In the recycling process of waste plastic using coke oven, sub-bituminous coal and added 5 vol. % of plastics are carbonized and changed into coke of optimal properties, tar and gas .
Carbon particles in mine-stone dumps after bituminous coals mining
Sýkorová, Ivana ; Havelcová, Martina ; Klika, Z. ; Trejtnarová, Hana ; Fojtíková, M. ; Šulc, Alexandr
The influence of heating on optical properties and morphology of organic matter was studied in mine-stone dumps in three districts in the Czech Republic.
Organic compounds in hardcoal waste piles studied by GC/MS and Py-GC/MS
Havelcová, Martina ; Sýkorová, Ivana ; Klika, Z. ; Trejtnarová, Hana ; Fojtíková, M.
GC/MS and Py-GC/MS techniques were used to provide information on set of samples from three waste piles localities in Czech Republic. Substituted and unsubstituted phenantrenes and other polycyclic aromatic hydrocarbons were comprised in sample extracts. The results were correlated with petrographic composition.

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