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Bis(phosphinates)
Křečková, Pavlína ; Kubíček, Vojtěch (advisor) ; Schulz, Jiří (referee)
Title: Bis(phosphinates) Autor: Pavlína Křečková Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: RNDr. Vojtěch Kubíček, Ph.D. Supervisor's e-mail address: kubicek@natur.cuni.cz Abstract Four geminal bis(phosphinate) acids were prepared and characterized by TLC, NMR, MS, EA. The compounds were acquired in high yields (over 55 %). Stability of these compounds was tested in chosen aqueous buffers, which covered a wide range of pH. The experiments showed that the prepared compounds are not fully stable. Performed experiments have shown negligible sorption of synthesized bis(phosphic) acids to hydroxyapatite, which was used as a model of bone tissue. Keywords: geminal, bis(phosphinate), decomposition, sorption.
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Adsorption of radionuclides in granite pores and micropores
Šindelář, Jakub ; Mls, Jiří (advisor) ; Šantrůček, Jaromír (referee)
Adsorption of radionuclides in granite pores and micropores ABSTRACT This graduation thesis deals with laboratory determination of adsorption isotherms parameters. Granite from the central moldanubian pluton, site Panské Dubenky, Czech Republic, was chosen to the experiment. The place is one of the candidate sites to build a deep nuclear waste disposal. A batch experiment was performed in two modes, differing in the way of addition of radioactive nuclide 90 Sr. From this experiment, distribution coefficients for a linear isotherm or parameters for Langmuir isotherm were obtained. Beside this, a through-diffusion experiment was performed. The objective of this experiment was to identify whether some of the radionuclides used (137 Cs, 90 Sr, 125 I) is able to penetrate through the pores of a granite slice barrier between two solutions of different concentrations. During the period of the experiment no radionuclide was detected reliably.
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Methylene-bis(phosphonate) derivatives for modification of biomolecules
David, Tomáš ; Lorenc, Miroslav (referee) ; Kubíček, Vojtěch (advisor)
5 Title: Methylene-bis(phosphonate) Derivatives for Modification of Biomolecules Author: Tomáš David Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: RNDr. Vojtěch Kubíček, Ph.D. Supervisor's e-mail address: vvvojta@seznam.cz Abstract The aim of this work was to prepare derivatives of methylen-bis(phosphonic) acid. Thirty compounds (from which 29 are new) were prepared with moderate or good yields. All compounds were fully characterized by NMR and MS. Four new crystal structures were obtained by RTG monocrystal analysis. Derivative containing 4-nitrobenzyl group in the side chain was used for study of bis(phosphonates) adsorption parametres to hydroxyapatite (with quantification by UV-Vis spectroscopy). Several derivatives containing characteristic functi- onal groups (-NH2, -COOH, -NCS) were prepared. These compound are suitable for further derivatization, mainly for conjugation with more complex structures through amide bond or thiourea bridge. Conjugates of building blocks with fluorescent probe (fluorescein and dansyl) were prepared for potencial optical imaging. Further modification of one of the dansyl derivative afforded trifunctional molecule - contating bis(phosphonate) as a vector for a bone tissue, a fluorescent probe for a possible fluorescent imaging and a free...
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Risk element sorption on waste materials from olive oil production
Hovorka, Miloš ; Száková, Jiřina (advisor) ; Trakal, Lukáš (referee)
The main objective of this thesis is to verify the efficiency of waste material from olive oil production to immobilize risk elements Pb, Cd and Zn in extremely contaminated soil and to verify following hypothesis: application of waste material from olive oil production will limit the availability of risk elements in the soil and also improves a supply of soil available nutrients and biological properties of the soil. The work is divided into two parts, theoretical part (literature review) and experimental part.
The theoretical part contains a general description of the risk elements and their possible harmful effects on living organisms, indicating their possible sources of entry into the environment, describes the behavior of these elements in the soil, especially events that contributes to the retention of soil. Furthermore, there are some possible methods for remediation of soil contaminated with hazardous elements and is described in more detail immobilization technique using soil improvers. In this chapter is devoted to the waste material from olive oil production, whose properties are tested in the experimental part of this work.
The experimental part is focused on verification sorption capability of waste material from olive oil production for selected risk elements. As a waste material has been used dry olive residue (known as DOR), and DOR after remediation of these types of fungi: Penicillium chrysogenum, Coriolopsis floccosa, Bjerkandela adusta and Chondrostereum purpureum. Analytical methods were used to determine the concentrations of the elements, the pH, the point of zero charge (pHpzc), and cation exchange capacity (CEC) for the individual samples representing material DOR and DOR after remediation of certain species of fungi. The preliminary sorption experiment determined sorption efficiency for the elements Cd, Pb and Zn for all the material tested. Stability of the risk element bonds was verified via model desorption experiment. Model laboratory incubation experiment was carried out to assess the potential changes of hazardous elements mobility in the contaminated soil, depending on dose and type of DOR material. At the same time there were determined contents of available proportions of essential elements in the soil. The contents of elements were determined by atomic spectrometry (ICP-OES) and the results analyzed by adequate statistical methods.
Results showed good sorption capacity of the waste material DOR, especially after transformation with different species of fungi, for hazardous elements and particularly Pb, less then Cd and Zn. The desorption experiment, however, showed unstable linkages elements in samples DOR, particularly in the case of Zn, which is also reflected in the incubation experiment. This instability is probably due to the low pH material DOR, therefore it would be useful for further research take into account the increase of pH levels of these samples. In terms of elemental composition appears to be biotransformed DOR as a good source of nutrients. The treatment of thesoil increased accessibility of nutrients such as Cu, Fe and Mn for plants.
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Non-energy Applications of Lignite
Majzlíková, Petra ; Maršálek, Roman (referee) ; Janoš, Pavel (referee) ; Pekař, Miloslav (advisor)
This thesis deals with various physical-chemical aspects of agricultural and environmental applications of the South Moravian lignite. The main attention was paid to the behavior of lignite in an aqueous environment and the application potential of lignite as a cheap, effective and universal sorbent. In the experimental part of the thesis, aqueous extracts of lignite were characterized in detail (by measurement of pH, conductivity, and by the qualitative and quantitative determination of inorganic constituents). The high sorption affinity towards polar (cationic dyes) and nonpolar compounds (petroleum products) was confirmed experimentally. At last, simple methods of the laboratory preparation of lignite granules was designed and optimized. The main aim of this part was to combine the unusual sorption properties of lignite with an improvement of the end-use properties of the product (user-friendly handling, controlled release of the lignite into the aqueous environment, etc.). The thesis represents a complex compilation of the results of pilot experiments which represent the starting point of detailed future works focused on the non-energetic application of this valuable natural material.
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Lightweight plasters of modified composition for final surface treatment of ETICS
Neubauerová, Alena ; Ševčík, Milan (referee) ; Bydžovský, Jiří (advisor)
The diploma thesis is focused on the verification of the parameters of thin lightweight mineral plasters with modified composition. As alternative raw materials are used expanded perlite Vapex, calcined diatomite Celite and powder waste glass of fluorescent lamps. In the theoretical part is summarized knowledge from completed studies dealing with the issue of compensation porous filler component. In the experimental part is tested consistency of fresh mixture, physical-mechanical, sorption and thermal insulating characteristics. It is compared the appearance of the surface and summarized the results of measuring.
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Sorption of metal ions mixture on natural lignite
Doskočil, Leoš ; Taraba, Boleslav (referee) ; Pekař, Miloslav (advisor)
Sorption of quaternary metal ions (Pb2+, Cu2+, Cd2+ and Zn2+) was carried out on lignite from the South Moravia. Following experiments were tested: kinetic sorption, dependence of sorption on pH, initial concentration, temperature, effect of electrolytes (KNO3 and NaCl) and desorption in deionized water. Sorption studies was carried out in quaternary mixtures and in the case of inicial concentration effect additional in a single-component solution. The batch sorption experiments was used. Sorption time was 24 hour, although concentration of ions was a near equilibrium after two hour. As the optimal pH was determined pH 5. The order of affinity by lignite was obtained Pb >> Cd > Zn > Cu for the sorption of metals in the single-component solution and the order was Pb > Cu > Zn > Cd for the sorption of mixture of metals. The maximum adsorptium capacities from single solutions were for Pb 97,82 mg/g, Cd 60,34 mg/g, Zn 49,88 mg/g and Cu 30,28 mg/g and in the case of ones from mixture solutions were for Pb 39,03 mg/g, Cu 25,94 mg/g, Zn 15,21 mg/g and Cd 5,18 mg/g. Experimental data have been analysed using Langmuir and Freundlich model. Thermodynamic values H°, S° and G° were calculated. Desorption test showed that desorption efficiency is 0–3 %. NaCl had the greatest influence on sorption from electrolytes. On the basis obtained results we can say that metals are binding to lignite in particular due to chemical interactions. Lignite is s suitable as a sorption material for metal ions especially in the field of low concentrations.
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Study on sorption of inorganic nutrients on lignite
Vahala, Jan ; Klučáková, Martina (referee) ; Sedláček, Petr (advisor)
Although lignit represents a valuable chemical substrate, it has been utilized mostly as a fuel in energetic industry. This application is not cost-effective at all and provides a negative ecological impact. Therefore, this bachelor thesis focuses on sorption properties of lignite utilizable in its alternative, mostly agricultural applications. Experimental part of the work deals with sorption and desorption of model inorganic nutrients (nitrates and phosphates as main components of standard inorganic fertilizers). Results of the experiments provides closer view on an application potential of lignite as a carrier of these nutrients or as an organic supplement to traditional NPK agricultural fertilizers.
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Humic substances - colloidal transport system of plant nutrients
Hudlíková, Iva ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The thesis deals with humic substances as major components of soil organic carbon during nutrients transport to plants root system. Literature research is focused on humic substances, adsorbing complex and transport of soil substances to plants. The experimental part of the work concentrates on interaction of humic acid with nitrates. A part of the work was humic acid characterization, and determination of titratable acidity and acidity COOH values.
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