The past few years have seen a rapid expansion in interest in the characterization of the entire complement of proteins, or proteome. Micro total analysis systems (μTAS) are an emerging promising method, offering rapid, sensitive and low sample consumption separations. I have demonstrated microchip capillary electrophoresis (CE) devices made of CaF2. New methods have been developed for micromachining enclosed capillaries in CaF2. CE analysis of fluorescently labeled amino acids was used to illustrate bioanalytical applications of these microdevices. Initial on-chip infrared spectroscopy results for qualitative analyte identification were achieved in microfluidic CaF2 channels. I have also shown the evaluation of poly(methylmethacrylate) (PMMA) and thermoset polyester (TPE) microchips for use in protein profiling. To improve separation efficiency and reduce protein adsorption, dynamic coating and poly(ethylene glycol) (PEG) grafting using atom transfer radical polymerization (ATRP) have been used in PMMA microdevices. Proteins, peptides and protein digests have been separated electrophoretically in these PMMA microchips. My results demonstrate that PMMA microdevices should be well suited as microfluidic systems for high performance separations of complex biological mixtures. In-channel ATRP has been developed for the surface modification of TPE microdevices. Characterization indicates that PEG-modified microchannels have much lower and more pH-stable electroosmotic flow, more hydrophilic surfaces and reduced nonspecific protein adsorption. CE of amino acid and peptide mixtures in these PEG-modified TPE microchips had good reproducibility. Phosducin-like protein and phosphorylated phosducin-like protein were also separated to measure the phosphorylation efficiency. My results show that PEG-grafted TPE microchips have broad potential application in biomolecular analysis. Cancer marker analysis is important for medical research and applications. I report a method that can covalently attach appropriately oriented antibodies of interest on monolith surfaces. To reduce nonspecific adsorption, protein solutions were used to effectively block the monolith surface. Selective preconcentration and elution of human chorionic gonadotropin have been performed in my affinity columns, demonstrating that this type of system should have promising applications in cancer marker detection.

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Les recherches présentées dans ce manuscrit s’articulent autour de deux parties distinctes. La première partie concerne une étude mécanistique de la réaction de décomposition de l’acide formique (AF) photocatalysé par le Tetra-n-ButylAmmonium DecaTungstate (TBADT) et explore la réactivité de ce photocatalyseur envers l’AF. La deuxième partie de ces travaux se focalise sur l’étude de la réactivité radicalaire d’anions phosphorés et de leurs analogues chalcogénés. Dans un premier temps, nous nous sommes intéressés à exploiter la réactivité de phosphures-borane et des anions d’oxydes de phosphine pour la formation de liaisons C-P par photo-induction dans le visible. Dans un second temps, nous avons exploré la réactivité radicalaire et ionique des phosphures-borane chalcogénés, par une étude de leur structure et de leur réactivité. Ces propriétés ont été mises en application dans le cadre de réactions de photo-polymérisation radicalaire et de réduction de composés électrophiles. / This dissertation is organized in two distinct parts. The first one is a mechanistic investigation of the photocatalyzed reaction of decomposition of formic acid (AF) under mild conditions using Tetra-n-ButylAmmonium DecaTungstate (TBADT). The second part of this work revolve around the use and study of the radical reactivity of phosphorous anions and their chalcogenated analogues. Firstly, we used the radical reactivity of phosphido-borane and phosphine oxide anions for the formation of C-P bonds. In a last part, we explored the radical and ionic reactivity of chalcogenated phosphido-borane, by studying their structure and reactivity. These properties has been applied to radical photo-polymerization reactions and for the reduction of electrophiles.

Nuage d'atomes de rubidium refroidi par laser. Ces mesures fournissent des informations sur la sourceet sur le milieu de propagation. Je considère une configuration particulière en transmission, le laserse propageant au travers du nuage atomique. Cette géométrie est pertinente pour étudier différentespropriétés, comme le mouvement des atomes. Cependant, le bruit intrinsèque du laser a unecontribution importante sur les spectres de bruit. Ce bruit technique peut alors devenir gênant pourextraire le signal étudié et une bonne compréhension du phénomène est donc essentielle.Expérimentalement, les spectres de bruit en intensité montrent un comportement différent auxfréquences basses et hautes. Alors que l'on observe la conversion "standard" du bruit de fréquence enbruit d'intensité pour les fréquences basses, la résonance atomique correspondant à un discriminateurde fréquence, des différences apparaissent à hautes fréquences. Nous montrons qu'une approche dechamp moyen, en associant une susceptibilité électrique au nuage atomique, est suffisante pourexpliquer les observations. Partant de ce modèle, les spectres permettent d'extraire des informationsquantitatives sur le laser et sur le nuage atomique. Ceci est connu sous le nom de spectroscopie debruit.La perspective est d'utiliser ces mesures de bruit afin d'obtenir une signature claire du laser aléatoireà atomes froids en étudiant la cohérence temporelle de la lumière émise. Cette thèse expose unerevue du phénomène de laser aléatoire, en particulier sur le laser à atomes froids et ses propriétés decohérence / In this thesis, I present some measurements of fluctuations of light after interaction with a cloud oflaser-cooled rubidium atoms. These measurements can provide useful information on the sourceitself as well as on the medium in which light propagates. I address a particular configuration inwhich intensity noise are measured on a laser beam transmitted through the atomic cloud. Thisgeometry is relevant to investigate different properties, such as the atomic motion. However, in ourexperiment the intrinsic noise of the incident laser has an important contribution to the detected noisespectrum. This technical noise may be hard to distinguish from the signal under study and a goodunderstanding of this process is thus essential.Experimentally, the intensity noise spectra show a different behavior for low and high Fourierfrequencies. Whereas one recovers the "standard" frequency to intensity conversion at lowfrequencies, due to the atomic resonance as a frequency discriminator, some differences appear athigh frequencies. We show that a mean-field approach, which corresponds to describing the atomiccloud by a dielectric susceptibility, is sufficient to explain the observations. Using this model, thenoise spectra allow to extract some quantitative information on the laser noise as well as on theatomic sample. This is known as noise spectroscopy.The perspective of this thesis aims at applying noise measurement to obtain complementarysignatures of the cold-atom random laser by studying the temporal coherence of the emitted light.The manuscript therefore outlines a review on random laser phenomena with a focus on cold-atomrandom lasers and its coherence properties

The “475°C embrittlement” occurring in ferritic and duplex stainless steel is considered to be detrimental and it limits the application of ferritic and duplex stainless steel at elevated temperatures, i.e., above about 300°C . In this study, the effect from alloying elements Ni, Cu and Mn on 475°C embrittlement was examined based on microhardness measurement and Charpy V-notch tests as well as atom probe tomography (APT). It was found that, after aging for 10h, 3% Ni accelerates the ferrite decomposition dramatically, 5% Mn has minor effect and no effect of 1.5% Cu was seen. The hardness increase tested at 450°C and 500°C was consistent with the observations from APT. The embrittlement based on room temperature Charpy tests was observed mainly during the first 10h. The embrittlement in Fe-20Cr-3Ni alloy was attributed to ferrite decomposition, while the other three alloys may be influenced by other phenomenon as well. A clustering effect of Cu has been observed in Fe-20Cr-1.5Cu and it was supposed to contribute to the mechanical changes.

The “475°C embrittlement” occurring in ferritic and duplex stainless steel is considered to be detrimental and it limits the application of ferritic and duplex stainless steel at elevated temperatures, i.e., above about 300°C . In this study, the effect from alloying elements Ni, Cu and Mn on 475°C embrittlement was examined based on microhardness measurement and Charpy V-notch tests as well as atom probe tomography (APT). It was found that, after aging for 10h, 3% Ni accelerates the ferrite decomposition dramatically, 5% Mn has minor effect and no effect of 1.5% Cu was seen. The hardness increase tested at 450°C and 500°C was consistent with the observations from APT. The embrittlement based on room temperature Charpy tests was observed mainly during the first 10h. The embrittlement in Fe-20Cr-3Ni alloy was attributed to ferrite decomposition, while the other three alloys may be influenced by other phenomenon as well. A clustering effect of Cu has been observed in Fe-20Cr-1.5Cu and it was supposed to contribute to the mechanical changes.

Georges Lemaître is quite unknown in Czech society. Although he was one of the scientists who independently anticipated the expansion of the cosmos and later formulated one of the most important hypotheses of the twentieth century - the hypothesis of the Primavel Atom, generally known as the Big Bang Theory as well as he was the president of The Pontifical Academy of Sciences, there has been published almost nothing about him in the Czech Republic. What was Lemaître's life like? What does his hypothesis mean in the context of Christian astronomical discourse of last centuries? How was his mission of the priest linked with work in astrophysics and mathematics?

The purpose of this work was the synthesis of functional amphiphilic gradient copolymers by means of controlled radical polymerizations, more precisely Atom Transfer Radical Polymerization. Two different monomer combinations, tert- and n-butyl methacrylate and tert-butyl and benzyl methacrylate, were copolymerized. In a first step seven different linear statistical copolymers were synthesized by means of batch polymerization. They were used as comparative material and the analysis of the reaction kinetic yielded the effective rate constants and the copolymerization parameters of the monomers in the particular monomer systems. Furthermore required for gradient polymer syntheses AB-di-block copolymers were synthesized as a second kind of comparative material. With the results of the kinetic analysis the monomer addition programs for the semibatch polymerizations were calculated to prepare gradient copolymers. Four different gradient copolymers with different compositions of tBMA and nBMA (ftBMA= 0.5, 0.65, 0.75, 0.85) and one gradient copolymer of tBMA and BzMA (ftBMA= 0.5) were synthesized. All semibatch reactions proceeded controlled, i. e. with mostly suppressed termination reactions. The compositions of the resulting copolymers exhibited ''double-gradients''. The point of change of the compositions were located at 16%, respectively 11% of conversion. The effective compositional gradients φ = dF1/dp were φ = 0.53, 0.46, 0.28, 0.15 and 0.43. A systematic correlation between the thermal behavior of the gradient copolymers and their composition was not found, as opposed to the statistical and the di-block copolymers. Semibatch synthesis with online infrared-spectroscopy observation to control the monomer feed during the synthesis were used for the polymerization of gradient copolymers. It was not possible to calculate the change of compositions of the polymers because it was not known how much monomer was injected at a certain time of the polymerization. A second problem was that the experimental set-up was not gas-tight. Hence, oxygen led to termination reactions. Three different kinds of hydrolysis were investigated for the cleavage of the tert-butyl groups on the polymer chains. The obtained gradient copolymers were hydrolyzed with methanesulfonic acid to obtain the intended amphiphilic polymer chains. All reactions proceeded with quantitative conversion. Hence, functional amphiphilic copolymers were obtained.

The cast products Mg–Sn based alloys are promising candidates for automobile industries, since they provide a cheap yet thermally stable alternative to existing alloys. One drawback of the Mg–Sn based alloys is their insufficient hardness. The hardenability can be improved by engineering the microstructure through additions of Zn to the base alloy and selective aging conditions. Therefore, detailed knowledge about the microstructural characteristics and the role of Zn to promote precipitation hardening is essential for age hardenable Mg-based alloys. In this work, microstructural investigation of the Mg–1.4Sn–1.3Zn–0.1Mn (at.%) precipitation system was performed using TEM. The chemical composition of the precipitates was analyzed using EDS. APT was employed to obtain precise chemical information on the distribution of Zn in the microstructure. It was found from microstructural studies that different precipitates with varying sizes and phases were present; lath-shaped precipitates of the Mg2Sn phase have an incoherent interface with the matrix, unlike the lath-shaped MgZn2 precipitates. Furthermore, nano-sized precipitates dispersed in the microstructure with short-lath morphology can either be enriched with Sn or Zn. On the other hand, APT analysis revealed the strong repulsion between Sn and Zn atoms in a portion of the analysis volume. However, larger reconstruction volume required to identify the role of Zn is still limited to the optimization of specimen preparation.

Les travaux exposés dans ce manuscrit ont pour objectif d'étudier des séquences réactionnelles organocatalysées asymétriques tournées vers l'obtention de composés polycycliques. Ces composés, présents dans certains composés naturels, sont aussi fluorescents. Le manuscrit débute par une introduction sur les molécules polycycliques et les différents modes d'activation en aminocatalyse ainsi que leur combinaison dans des réactions en cascade. Le premier chapitre traite de l'obtention de dérivés tricycliques d'indole et d'indazole par une cascade réactionnelle de type addition d'aza-Michael/aldolisation aminocatalysée énantiosélective. Le deuxième chapitre vise à étudier le comportement solvatofluorochromique de quelques analogues des composés synthétisés dans le premier chapitre ainsi que l'influencedes différents groupements fonctionnels de la molécule sur ces propriétés. Le troisième chapitre décrit la synthèse decomposés tricycliques entièrement carbonés à partir de 2-naphtols. Cette stratégie en cascade aminocatalysée et asymétrique repose sur une séquence alkylation de Friedel-Crafts/aldolisation. / The work presented in this manuscript aims to study organocatalyzed asymmetric reaction sequences focused on thesynthesis of polycyclic compounds. These compounds, found in some natural products, are also fluorescent.The manuscript starts with an introduction to the polycyclic molecules and the different activation means used in aminocatalysis and their combination for cascade reactions. The first chapter presents the synthesis of tricyclic indole and indazole derivatives through an aminocatalyzed enantioselective aza-Michael addition/aldolisation reaction sequence. The second chapter is dedicated to studying the solvatofluorochromic behavior of some analogues of the compounds synthesized in the first chapter as well as the influence of the various functional groups born by the molecule on these properties. The third chapter describes the synthesis of fully-carbonated tricyclic compounds starting from 2-naphthols. This aminocatalyzed and asymmetric cascade strategy rests on an Friedel-Crafts alkyltion/aldolisation sequence