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Organomineral gel as a new concept of structural and colloidal characterization of soils
Kundera, Ondřej ; Záhora, Jaroslav (referee) ; Sedláček, Petr (advisor)
The aim of this study is the organomineral gel contained in soil, mainly the characterization using electron microscopy and available analytical methods like IR-spectrometry, thermal analysis, X-ray crystallography and emission spectrometry. The knowledge from this study may help to define function and significance of this gels to soils and nature. The theoretical part of this thesis deals with soil, humic substances and minerals occurring in soils. The experimental part solves especially the structure and further characterization of organomineral gels.
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Study of biological activity of superabsorption polymers
Männlová, Adriana ; Enev, Vojtěch (referee) ; Klučáková, Martina (advisor)
This thesis is focused on the study of the biological activity of superabsorbent polymers for environmental and agricultural applications. Generally these hydrogels perform many functions in the soil, which is increasingly stressed by treatment with synthetic fertilizers and thus loses their natural properties, such as the uptake of moisture. Addressing these issues is now in superabsorbent polymers that can absorb and also retain a lot of water around the root system as long as possible. They can perform the function of carriers gradual release fertilizer. Based on the literature review was designed and conducted the study of biological activity in the soil model on corn sown. SAPs were prepared in the framework of contract research Faculty of Chemistry of the Technical University in Brno with the company Amagro Ltd. The content of the experiment, the superabsorbent polymer, observing effects on the growth of dent corn. He was also studied root system for absorption of nutrients. Further changes were observed rheological properties of prepared superabsorbent polymer, superabsorbent polymers since they provide a source of nutrients and help to retain moisture in the soil, it is necessary to know their viskoelstick properties even at temperatures below freezing. This work is based primarily on the use of great motivation superabsorbent polymers in agriculture and also in environmental protection.
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Influence of humic substances on the broiler chicken´s meat
Novák, Tomáš ; Bušová, Milena (advisor) ; Daniel, Daniel (referee)
Due to great popularity of the chicken meat, the breeders try to improve yield of meat and its quality parameters, which leads to the application of various food additives such as those based on humic compounds. Those humic matters are used for their positive influence over the immunity system, metabolic functions and adaptability of the livestock organisms.
Literature review sums up the experience with broiler chicken breeding and feeding. Further it deals with meat composition and its characteristics. The last part contains information of humic compounds and their influence over the live organism and compares the findings about the application of humic preparation into the livestock food portion.
Practical part of this thesis researches the influence of humic preparation Humafit over the qualitative and quantitative parameters of the broiler chicken meat. Two groups of chicken were observed, experimental one and control one. Feeding of these two groups was held at the same time, whereas the experimental group was being fed with 200 ml of Humafit per 1000 l of supply water from 10th to 20th day of feeding. The research did not prove statistically important differences (p > 0.05) in chicken corpse weight such as in weight of each parts of the corpses.
Differences in the protein content in the breast muscle were also not statisticaly demonstrative such as pH value of the breast and thigh muscle. Total amount of heme pigments in breast muscle of the experimental group was higher and this difference was statistically important (p = 0.049). The breast muscle of chicken in the control group showed up higher binding capacity for water, this difference was statistically important (p = 0.041). This finding correlates with sensory analysis results (|r| = 0.691), when the panelists rated the meat of the control group chicken as more flavorous.
There is disunion among scientific studies in the opinion of humic compounds influence over the livestock organism. It is not possible to make a definite evaluation of humic compounds influence over the meat quality, because qualitative and quantitative parameters of the livestock meat depend on the number of intravital and external factors which can affect the experiment results.
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Humic substances as transport medium for plant nutrition
Vlková, Markéta ; Solná, Irena (referee) ; Klučáková, Martina (advisor)
This bachelor thesis treats about humic matters and their application in agriculture by means of hydrogels transport medium. It studies progressive releasing of substances, which could be used as more common nutrition for plants, prepared from superabsorbent polymers. Research was implemented in collaboration with industrial partners. The substances are synthetically made of sodium Lignohumate and mixture of industrial fertilizer called NPK. Released substances were characterized by using some methods. First, there were measured qualities, which didn’t specify released compounds, like swelling, conductivity, pH and absorption of hydrogels with different wavelengths. More details came with methods ICP-OES and ion chromatography. Hydrogels which contained both mixtures of matters written up, were studied in water solution for 5 weeks and every week all characterization were measured. From the results we can see that both of the mixtures decrease ability of hydrogel’s swelling, mainly NPK. Measuring of absorption showed that the most of the substances released from sodium Lignohumate were from hydrogels without NPK. By other measuring, we noticed realizing of potassium and phosphorus elements. The most of them were from hydrogels containing NPK. By measuring ion chromatography, we found chloride, phosphoric, sulfuric and nitric ions in solution.
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Material characterization of novel hydrogels containing humic substances intended for pharmaceutical and cosmetic applications
Pavlicová, Renata ; Weidlich, Tomáš (referee) ; Sedláček, Petr (advisor)
This thesis is focused on the development and characterization of hydrogels containing humic substances with possible use in cosmetic and pharmaceutical industries. This work follows on the bachelor thesis, theoretical and experimental part is based on already acquired knowledge. The aim of this work was to develop a literature review focusing on the potential use humic gels in practice and also to enhance the consistency of other active ingredients. Based on this literature review, the main aim was to prepare model humic hydrogels with selected active ingredients and their characterization by basic methods of material analysis. These basic methods were especially rheology and visual assessment of consistency during the preparation, then the samples were subjected process of drying and swelling. Experimental results showed considerable influences during the preparation and composition of each sample, which then reflected in their structure and consistency. Furthermore, it was found that the suitable composition and combination of ingredients form hydrogels acceptable characteristics for further use in cosmetic or pharmaceutical applications.
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Experimental study and modelling of the transdermal penetration of active species from gels
Palanová, Veronika ; Opatřilová, Radka (referee) ; Sedláček, Petr (advisor)
This diploma thesis deals with design and experimental study of transdermal transport of pharmaceutically active agents from gel matrices, which contain humic substance in its structure. A model absorption membrane was represented by the skin of pig´s earlobes. The study of the release of active substances and Lignohumte was performed due to the vertical diffusion cells. The amount of released humic substance was characterized by UV-VIS method and the amount of released active agent from gel matrix was determined by HPLC-DAD. The most interesting finding of this diploma thesis was that Lignohumate enhances transdermal transport of active agents and supports their release from gel samples to the particular environment.
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Study of Optical and Electrical Properties of Biomaterials
Flimelová, Miroslava ; Táborský, Petr (referee) ; Drbohlavová, Jana (referee) ; Weiter, Martin (advisor)
Studium nových materiálů potenciálně využitelných pro organickou elektroniku a fotoniku získává velmi důležitý význam z hlediska ekologie. Tato práce je zaměřena na studium vlastností biologických materiálů, které by našly uplatnění v aplikační sféře. Zájem o znalosti v oblasti základních a pokročilých vlastností organických a biologických materiálů, které mohou být potenciálně využity v oblasti organické elektroniky a fotoniky přináší nové otázky, které mohou přispět k rozvoji této oblasti. Ke studiu základních procesů souvisejících s optickými a elektrickými vlastnostmi materiálů, jako je například přenos náboje, jsme využili různé techniky a metody charakterizace. První část práce je zaměřena na souhrn vlastností anorganických a organických materiálů umožňující jejich možné využití v organické elektronice a fotonice, druhá část práce poskytuje nejnovější přehled z oblasti pokročilých biologických materiálů a jejich vlastností související se záměrem této práce. Třetí část práce pak shrnuje experimentální metody a shrnuje získané výsledky. Nakonec je diskutován vztah mezi pozorovanými jevy a strukturou studovaných materiálů na molekulární úrovni.
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Spectrometric Methods for Research of Humic Substances
Enev, Vojtěch ; Maršálek, Roman (referee) ; Sýkorová, Ivana (referee) ; Klučáková, Martina (advisor)
The main aim of doctoral thesis is the study on physicochemical properties of humic substances (HS) by modern instrumental techniques. The subject of the study were HS isolated from South Moravian lignite, South Bohemian peat, forest soil Humic Podzol and finally extract from brown sea algae Ascophyllum nodosum. With respect on determination of structure and reactivity of these unique “biocolloids”, standard samples (Leonardite HA, Elliott Soil HS and Pahokee Peat HS) were also studied. These samples were obtained from International Humic Substances Society (IHSS). All mentioned substances were characterized by elemental analysis (EA), molecular absorption spectroscopy in ultraviolet and visible region (UV/Vis), infrared spectroscopy with Fourier transformation (FTIR), nuclear magnetic resonance spectroscopy of carbon isotope 13C (LS 13C NMR), steady-state and time resolved fluorescence spectroscopy. Obtained fluorescence, UV/Vis and 13C NMR spectra were used for calculation of fluorescence and absorption indexes, values of specific absorbance and structural parameters respectively, which were used for fundamental characterization of these “biocolloidal” compounds. Infrared spectroscopy with Fourier transformation was utilized for the identification of functional groups and structural units of HS. Evaluation of infrared spectra is quiet complicated by overlapping of absorption bands especially in fingerprint region. This problem was overcome by Fourier self-deconvolution (FSD). Steady-state fluorescence spectroscopy was used for deeper characterization of HS with respect to origin, structural units, amount of substituents with electron-donor and electron-acceptor effects, content of reactive functional groups, “molecular” heterogeneity, the degree of humification, etc. Parameters of complexation of samples Elliott Soil with heavy metal ions (Cu2+, Pb2+ and Hg2+) were obtained by using modified Stern-Volmer equation. These ions were chosen purposefully, because the interaction of HS with these ions is one of the fundamental criteria for the assessment of the reactivity of HS. Key part of the whole doctoral thesis is time-resolved fluorescence spectroscopy. It is able to determine the origin of emission of HS by method Time-Resolved Area Normalized Emission Spectra (TRANES). The viscosity of micro medium about excited fluorophores of HS was determined by Time-Resolved Emission Spectra (TRES).
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Removal of Selected Components from the Aquatic Environment by Coagulation Process
Měřínská, Zuzana ; Márová, Ivana (referee) ; Janda, Václav (referee) ; Mergl, Václav (referee) ; Vávrová, Milada (advisor)
This thesis deals with coagulation treatment of surface water with content of humic matters, drug residues and turbidity. Commonly used coagulants (ferrous and aluminous sulphate) and natural biopolymer based on chitosan that not yet used in the Czech Republic had been studied. The aim of this work was to found the optimal application of chitosan in water treatment and comparison of its coagulation efficiency with standard inorganic coagulants. Theoretical part of the thesis contains occurrence, classification, composition, properties and importance of humic matters and drug residues and furthermore properties of chitosan and its using in water treatment. Experimental part summarizes the obtained results from the laboratory coagulation tests with inorganic coagulants and with chitosan leading to determination of its optimal dose. Other coagulation experiments were focused on finding the possibilities of combine the two coagulants (ferrous sulphate and chitosan) and to find their optimum doses and suitable ratio. The influence of pH on water treatment with using coagulation was also studied.
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Hydration of Humic Substances
Bursáková, Petra ; Šimon, Peter (referee) ; Slovák,, Václav (referee) ; Klučáková, Martina (advisor)
Tato dizertační práce studuje charakter hydratační vody v systému voda/huminová látka. Úkolem je určit jak kvantitativní, tak i kvalitativní aspekty hydratace huminových látek (HS) v pevné i kapalné fázi a prozkoumat rozdíly ve vlastnostech vody obklopující huminovou látku s použitím vysokorozlišovací ultrazvukové spektroskopie (HRUS) a metod termické analýzy, jako je diferenční kompenzační kalorimetrie (DSC) a termogravimetrie (TGA). Hlavním cílem této práce je přispět k objasnění problému hydratace huminových látek pocházejících z různých zdrojů a majících proto odlišné vlastnosti a složení, a to s využitím postupů a technik, které se již dříve osvědčily při stanovení hydratační vody v hydrofilních polymerech. Tato práce zkoumá účinek vody na strukturu huminových látek, způsob, jakým voda smáčí jejich povrch a jak jimi proniká, způsobuje změny v konformaci HS, jejich retenční kapacitu a také vliv původu jednotlivých huminových látek na jejich hydratační vlastnosti s ohledem na kineticku těchto procesů. Dále studuje vliv stupně humifikace na hydratační procesy huminových látek, stejně jako reverzibilitu těchto procesů. Výsledky této práce objasňují paralelu s vlastnostmi hydrogelů a podobnosti i odlišnosti mezi biopolymery a huminovými látkami.
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