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Utilization of Diffusive Techniques in Study on Reactivity of Biocolloids
Kalina, Michal ; Maršálek, Roman (referee) ; Mráček, Aleš (referee) ; Klučáková, Martina (advisor)
The main aim of this thesis is the utilization of simple diffusion techniques for the study on transport properties of copper ions in the systems containing humic acids with respect to the other parameters, which can affect the process (the structure of diffusion environment, the interactions between transported specie and diffusion matrices, selective blocking of binding sites of humic acids). The first part of experimental works was focused on characterization of studied materials (humic acids, humic sol and humic hydrogel). The main part of the thesis was dealing with the optimization of simple diffusion techniques, which were suitable for the study on transport of copper ions in matrices containing humic acids, taking into account the mutual interactions between studied components in the system. The obtained diffusion characteristics were compared to the data determined using sorption experiments. Consequently, the minor goal of the experimental works of this thesis was also the assessment of the influence of basic physico-chemical parameters of studied materials on transport phenomenon.
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The radio therapy process planning
Slavíček, Tomáš ; Kolářová, Jana (referee) ; Hrozek, Jan (advisor)
This thesis aims to bring reader to the problems of radiotherapy, to give him an overview of basic principles and methods used to treat patients with cancer by ionizing radiation. The first part is devoted to the physical description of radiation and means of quantification. Interactions of radiation with matter are discussed next following with characterization of radiation effects on living cells and tissues. In the next part there is a description of the devices used in the treatment by ionizing radiation and an explanation of the various acts of patient's preparation from the target localization to irradiation. The final chapter describes created program with a graphical environment, which includes the key elements of commercial planning systems for the creation of the irradiation plan. This program uses real CT images and provides the user a basic idea of creating radiotherapeutic plan. The user has several functions for creating and optimizing the plan. The output of the program is a graphical representation of the spatial distribution of dose in the patient's body.
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Application of different fractionation techniques for structure determination of ICP
Dostálová, Dagmar ; Kratochvíla,, Jan (referee) ; Buráň,, Zdeněk (advisor)
Impact E/P copolymer (ICP) is produced using gas-phase polymerization catalysed by Ziegler-Natta catalysts. This material with its excellent mechanical properties is used in many industries, for example in automotive industry to produce bumpers or instrument panels. Its properties depend on chemical structure which was analysed using DSC, 13C NMR and GPC. It was used 6 different samples of ICP for studies, the chosen samples have different ratio between ethylene and propylene in their copolymer phase. The samples were fractionated using preparative TREF and solvent extraction to obtain fractions, which composition depends on elution temperature. Obtained fractions and original samples were subsequently analysed using above-mentioned methods.
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Fractionation of humic acids isolated from lignite
Moťka, Pavel ; Barančíková, Gabriela (referee) ; Klučáková, Martina (advisor)
The diploma thesis deals with lignitic humic acids. Bibliographic search can be divided into three parts. The aim of the first part is characterization of humic substances, presence, composition, structure and exploitation especially of humic acids. The second part describes a division of heterogeneous mixture of humic acids into closed fractions with more specific properties. The final part is a study of solubility of humic acids. The experimental part of the diploma thesis is structured similarly. In this work, a gradual fractionation with pH is used. Obtained fractions were characterized by UV/VIS and FT-IR spectroscopy. We assessed the portion of ash and carboxyl groups have been identified. Subsequently, all fractions extracted by gradual fractionation as well as some soluble fractions obtained by direct fractionation have been analyzed in view of solubility and their behaviour in water environment. Both used methods were compared.
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Influence of E/P copolymer composition on impact copolymer properties
Dostálová, Dagmar ; Kučera, František (referee) ; Buráň, Zdeněk (advisor)
Houževnatý E/P kopolymer se vyrábí polymerací v plynné fázi, která je katalyzovaná Ziegler–Nattovými katalyzátory. Tento materiál s výbornými mechanickými vlastnostmi je používán v mnoha průmyslových odvětvích, např. v automobilovém průmyslu na výrobu nárazníků aut a palubních desek. Jeho vlastnosti závisí na chemické struktuře, která byla zkoumána pomocí metod DSC, SSA, 13C NMR, ATREF a FTIR. Výsledky analýz byly porovnány s mechanickými vlastnostmi vzorků - modulem pružnosti v ohybu a nízkoteplotní vrubovou houževnatostí dle Charpyho. Pro studium vlivu složení na mechanické vlastnosti bylo použito 5 různých vybraných vzorků houževnatého kopolymeru E/P s různým poměrem ethylenu a propylenu v kopolymerní fázi, které byly frakcionovány pomocí o-xylenové extrakce za účelem rozdělení materiálu na krystalickou část, složenou z krystalického E/P kopolymeru a PP, a amorfní část, tvořenou E/P kaučukem. Získané frakce i původní vzorky byly následně analyzovány výše uvedenými metodami.
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Speciation and fractionation analysis of metals in agricultural soils
Lepař, Petr ; Mládková, Zuzana (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with the procedures and analytical techniques associated with speciation analysis and fractionation of metals in agricultural soils. The first part defines the basic concepts related to speciation, fractionation, soils and elements contained within it. The following chapters describe procedures of samples withdrawal and its adjustment including a description of some methods used for the purpose of extraction, fractionation and speciation analysis. The last chapter is devoted to listing of some separation techniques and instrumental methods used for the purposes of speciation and fractionation.
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Radiotherapy of breast cancer
TRAKALOVÁ, Barbora
Diagnosis code C50 represents malignant neoplasm of breast. It is the most frequent tumour disease in women. In 2009, 5975 cases were newly diagnosed in women in the Czech Republic and 1607 women died of this disease. There exist many risk factors which can cause tumour such as hereditary disposition, age, menses, menopause and other factors. At the same time, we can influence many factors and so prevent the disease. Prevention is also important, whether in the form of self - investigation of breast or mammography screening, which is recoverable by insurance from the age of 45. Treatment of breast carcinoma includes a lot of medical modalities such as surgical, hormonal and biological treatment, chemotherapy and radiotherapy. This thesis deals in more details with radiotherapy which is irreplaceable in treatment of this disease. Radiotherapy is a treatment of malignant and benign tumours by means of ionising radiation. In order to treat patients with radiotherapy, a team of doctors and radiologists shall create an individual radiation plan for them including the exact target volume, critical organs, radiation technology, fractionation and particular radiation exposure, radiation position and many other data necessary to accurate irradiation. A technology of two tangential fields is the most applied technology at breast cancer treatment. This technology is also applied in Nemocnice České Budějovice a.s. where I have created a file of 60 patients with breast carcinoma treated on oncology department in the year 2011. There have been used 536 verification images on the whole, it means 1608 evaluation. In course of treatment a patient should have an identical radiation position, which is reached with irradiation and fixation aids. However, from various reasons small or bigger deviations from the optimal position happen and therefore a possibility of irradiation of another volume than the required target one can occur. It is necessary to be aware of the fact that during a treatment of oncology patients there can often appear change of weight, change of body shape of a patient and at advanced stages even also change of physical state and movability of a patient. Therefore large deviations can happen in patients with breast carcinoma namely for example in case of breast deformation or abnormal loss of weight due to the treatment. In Nemocnice České Budějovice a.s., the maximum allowed deviation for vertical, lateral and longitudinal axis is stated 0,7 cm and for rotation 3°. I have noticed the acquired deviation values from verification images into a chart and consequently into a figure where are shown the average deviations and frequencies of these deviation in particular axes for each radiation field. The biggest deviation has happened in vertical axis and the average deviation in that axis was 0,29 cm. The maximum allowed deviation was exceeded only at 3 %, so at 45 deviation from the total evaluation. This thesis should prove the fact that verification images enable to prevent possible errors during radiotherapy. This hypothesis has been confirmed because only 3 % evaluation exceeded the maximum allowed deviations. Verification images enable us to disclose wrong irradiation position, therefore only the target volume is irradiated and follows no irradiation of the surrounding healthy tissue and critical organs.
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Indirect speciation of mercury in soils and sediments with cold vapor atomic absorption spectrometry.
ŠPAČKOVÁ, Jitka
In the diploma thesis have been tested four extraction techniques for isolation of organic forms of mercury from sediments (liquid liquid extraction, microwave extraction in liquid liquid extraction, solid phase extraction and extraction with use of ionic exchange) followed by determination of mercury by atomic absorption spectrometer AMA?254. It has been achieved great results during liquid liquid extraction likewise ionic exchange extraction. Reached percents of orgHg were in accord with certified reference material for sediments CRM-580 and corresponded to 86,44 ? 16,63 %, resp. 87,01 ? 29,22 %. Thanks to a simple procedure, extraction speed and ease of determination of organic forms of mercury contain was first of all (in the first instance) verified a method with use of ionic exchange, whose principle and procedure is very elementary. This technique was applied to a number of real sediment samples collected from water tanks Jordan and Skalka. It was approved that this method has been presenting a suitable alternative to chromatographic methods or methods of electro?migration.
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