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Contour methods in the mathematical theory of phase transitions
Nagy, Oliver ; Zahradník, Miloš (advisor) ; Netočný, Karel (referee)
Title: Contour methods in the mathematical theory of phase transitions Author: Oliver Nagy Department: Department of Mathematical Analysis Supervisor: doc. RNDr. Miloš Zahradník, CSc., Department of Mathematical Analysis Abstract: This thesis concerns itself with three topics, namely polymer models, Pirogov-Sinai theory and one-dimensional Dyson models. It contains a short introduction into all three topics. The introduction to Pirogov-Sinai theory will serve as a starting point for a future expanded introductory exposition, since such a material is missing in the contemporary literature. Research result of the first chapter is a detailed combinatorial analysis of cluster expansion of hard-core repulsive polymer model based on 'self-avoiding polymer trees', leading to simplification of the structure of summation in the partition function. In the case of Dyson models we suggest an alternative definition of contours for the one-dimensional Dyson model with the exponent of polynomially-decaying interaction p ∈ (1, 2) that is usable for study using Pirogov-Sinai methods. Keywords: Contours, polymers, cluster expansion, Pirogov-Sinai theory, Dyson model;
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Use of polymers in road constructions
Klusková, Jana ; Komenda, Radek (referee) ; Stehlík, Dušan (advisor)
The diploma thesis deals with the use of recycled polymers in asphalt mixtures. In the theoretical part of the thesis there is discussed the global issue of plastic waste including the experience of foreign countries, where this technology has already been introducted and used. The practical part is devoted to the proposal of using recycled plastic in asphalt mixture, description of used laboratory tests and the evaluating the effect of low-density polyethylen (LDPE) on the asphalt mixture type AC. There were performed tensile strenght tests, water resistant tests and stiffness modulus tests in the laboratory (E). The output of this work is an evaluation of measured values, processing of results and their interpretation depending on the possible use of this technology in Czech republic.
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X-ray nano computed tomography of structured polymeric biomaterials
Kalasová, Dominika ; Oberta,, Peter (referee) ; Kataja, Markku (referee) ; Kaiser, Jozef (advisor)
Tato práce se zaměřuje na pokročilou zobrazovací technologii, rentgenovou počítačovou tomografii (CT). Tato nedestruktivní technika je využívána pro výzkum různých biomateiálů ve tkáňovém inženýrství a materiálové vědě obecně (skafoldy, polymery, keramické materiály, kompozity aj.). Vizualizace a kvantifikace ve 3D jsou výhodné v rámci multidisciplinárního přístupu, který je často v těchto odvětvích uplatňován. Záměr této práce lze rozdělit do dvou oblastí. Prvním tématem je optimalizace měřicí procedury různých měkkých materiálů pomocí CT s laboratorními rentgenovými zdroji. To zahrnuje převážně zobrazování ve fázovém kontrastu, konkrétně metodu volného šíření záření (VŠZ). Tato práce teoreticky popisuje VŠZ a demonstruje tento jev na řadě experimentů. Následné nezbytné zpracování dat získaných VŠZ je implementováno a vyhodnoceno na základě míry zlepšení obrazových dat. Druhé téma ukazuje konkrétní aplikace CT v materiálovém inženýrství. Několik studií s různými CT zařízeními ukazuje příklady možných aplikací a obrazového zpracování. Příklady korelace CT dat s jinými doplňkovými technikami ukazují, jak může být CT aplikována v multioborovém přístupu ke komplexnímu řešení vědeckých problémů.
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Hydrogen quantification by electron spectroscopy
Endstrasser, Zdeněk ; Polčák, Josef (referee) ; Čechal, Jan (advisor)
The absence of hydrogen in the photoelectron spectrum remains one of the greatest limitations of X-ray photoelectron spectroscopy. The main aim of this work is therefore to determine the concentration of hydrogen atoms in the near surface region of a sample. The REELS electron spectroscopic method based on quasi-elastic electron scattering is used for this purpose. The choice of this method was given mainly by the fact that the photoelectron spectrometers has an electron source in the basic equipment, so there is no requirement to purchase additional equipment. In our case, measurements were realized using the AXIS Supra photoelectron spectrometer in CEITEC laboratories. We were primarily focused on the study of polymer samples in this work. The gus cluster ion source was used for sputter cleaning of the sample surface. Then the XPS and REELS measurements were performed on such cleaned samples. The obtained data were subsequently evaluated, and the results discussed. The most important output of this work was to develop the methodology of detection and quantification of hydrogen atoms. However, the theoretical description of the methods used, and the appreciation of critical aspects associated with the use of the REELS method are also embraced. In particular, the effect of sample charging and electron dose on measurement results is discussed.
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Development of the poly(methylene blue) modified graphite electrodes for the electrochemical detection of hydrogen sulphide
Zlámalová, Magda ; Janda, Pavel ; Nesměrák, K.
A comparative study have been undertaken of the electropolymerization and electrochemical properties of deposited electroactive polymer on two different graphite electrode substrates: basal plane highly oriented pyrolytic graphite (HOPG) and pencil-graphite electrode (PGE). Poly(methylene blue) modified electrodes (HOPG/pMB and PGE/pMB) have been prepared by potential cycling in aqueous electrolyte solution containing methylene blue monomer. It has been found that electrochemical properties and electrocatalytic activity of deposited film are greatly influenced by the type of electrode substrate. Developed electrodes have been further investigated as potential sensors for hydrogen sulphide.
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The preparation and characterization of polymeric, enzymatically cleavable carriers for cancerostatic drugs
Zelený, Jan ; Etrych, Tomáš (advisor) ; Ječmen, Tomáš (referee)
As the development of cancerostatic drugs progresses it is becoming necessary to contemplate the question of how to deliver these drugs, which themselves tend to exhibit carcinogenic properties, effectively and accurately to the affected tissues and thus to circumvent their destructive effects upon the healthy parts of the organism. One approach to delivering drugs selectively to cancerous tissues is to make use of some of the specific properties which these tissues tend to possess, one of which being the so-called enhanced permeability and retention effect (EPR effect). This effect, which will be further discussed within this thesis, allows for macromolecules that are too massive to pass from the bloodstream into healthy tissue, to exit the blood vessels of cancerous tissue and to accumulate there. Therefore, a drug molecule can specifically enter cancerous tissue along with a suitable macromolecule, to which it is conveniently attached. If, moreover, the given drug is connected to the carrier molecule via an enzymatically cleavable spacer, it is possible to make use of lysosomal proteases (such as cathepsin B, which is overexpressed in some cancer cells) in order to attain its detachment from the carrier molecule and its subsequent activation. This bachelor thesis focuses on describing the...
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Moisture Effect On Electrical Properties Of
The Composite Epoxy Resins
Horák, Luděk
The thesis presented is focused on studying electroinsulating epoxy resin-based sealings. The aim of the thesis is to compare several sets of samples of composite epoxy resins with different kinds of micro-ground siliceous sand as a filling. The temperature and frequency dependence of relative permittivity and dissipation factor are measured for given samples.
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Polymeric delivery systems for immunooncotherapy
Šírová, Kateřina ; Etrych, Tomáš (advisor) ; Konvalinka, Jan (referee)
Oncological diseases are among the most common causes of death in developed countries and for some of them, current medicine still does not have satisfactory results. Designing of polymer therapeutics characterized by high molecular weight and controlled drug delivery is one of the perspective ways of development of new therapeutic protocols. Nowadays, scientists also focus on the research on anticancer immunological mechanisms and their potential use in cancer therapy. Constitutive activation of signal transducer and activator of transcription 3 (STAT3) has been described in many types of malignancies. The function of STAT3 is very complex, the aberrant activation in cells of tumor microenvironment is related to many predominantly prooncogenic processes. This bachelor thesis is focused on synthesis of peptide inhibitor of STAT3 signaling, phosphopeptide pYLPQTV, and its conjugates with polymer carrier based on N-(2-hydroxypropyl)methacrylamide (HPMA). The inhibitor and the polymeric conjugates have been characterized by several physico-chemical techniques; also, effect on proliferation of cancer cells have been tested in in vitro conditions, which proved slightly cytotoxic activity. A more detailed study and an optimization of methods for in vitro characterization will be necessary to further...
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Secondary electron hyper spectral imaging in helios nanolab - mapping materials properties or artefacts?
Rodenburg, C. ; Masters, R. ; Abrams, K. ; Dapor, M. ; Krátký, Stanislav ; Mika, Filip
A link between peaks in secondary electron (SE) spectra and Electron Energy Loss Spectra\n(EELS) was shown decades ago. Also, materials properties (bulk modulus, band gap)\ncorrelate with the bulk plasmon position in EELS, and local modulus maps in carbon fibres\nhave been presented. If any features as result of plasmon decay into SE can be identified,\nSE spectroscopy combined with hyperspectral imaging could transform the SEM into a tool\nfor mapping materials properties with ground-breaking potential for nanotechnology. To\nbecome a reality, we first need to establish SE collection conditions spectra that represent a\nmaterial reliably. Second, we need to gain a better understanding of the processes involved in the SE emission processes.
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