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Conception et évaluation de phases stationnaires chirales pour l'emploi en électrochromatographie capillaire ( Tubes ouverts et colonnes monolithes ) / Non-covalent and covalent chiral stationary phases for capillary electrochromatography based on β-cyclodextrins (OT-CEC and m-CEC)Lakhlifi, Mourad 27 November 2017 (has links)
Suite à la première thèse sur le greffage et l’adsorption physique successives de sélecteurs chiraux dans des tubes ouverts en électrochromatographie capillaire (ECC ou CEC) chirale, menée par le Dr Guillaume Pédéhontaa-Hiaa au sein de l’équipe du laboratoire COBRA (IUT d’Evreux), nous avons développé des phases stationnaires chirales covalentes (CSPs) à base de cyclodextrines (CDs) en tubes ouverts et des CSPs sur supports monolithiques pour l’emploi en CEC. Nous avons ainsi évalué les paramètres électrochromatographiques et la stabilité de ces CSPs en séparant une variété de racémiques neutres et chargés. L’influence de la température d’analyse, le potentiel appliqué ainsi que la nature et le pH des électrolytes sur la qualité des électrochromatogrammes ont été étudié en CEC chirale. Cette étude se divise en deux grandes parties. La première concerne les CSPs élaborées sur colonnes à tubes ouverts pour l’OT-CEC. Il s’agit initialement de graver la surface interne d’un capillaire de silice de 50 μm de diamètre interne à l’aide d’une solution de bifluorure d’ammonium dans le but premier d’augmenter considérablement sa surface spécifique et d’immobiliser en surface une grande quantité de sélecteurs chiraux à base de β-CD. Nous avons alors décrit des greffages covalents de CDs anioniques (Scc-β-CD et CM-β-CD) et d’un polymère anionique de CDs (p-CM-β-CD-) en surface de capillaire de gel de silice gravée et modifiée chimiquement par l’aminopropyltriéthoxysilane (APTEOS). Les greffages des sélecteurs ont été reproduits dans les mêmes conditions que dans la thèse rapportée précédemment en électrophorèse. L’originalité de la construction de ces CSPs réside dans la rapidité et la simplicité du couplage dit péptidique à température ambiante, des sélecteurs carboxylés sur des colonnes préalablement gravées. Ce greffage nécessite des agents de couplage peptidique solubles dans l’eau tels que 1-Ethyl-3-(diméthylaminopropyl)carbodiimide (EDC) et le N-Hydroxysuccinimide (NHS). Il peut aussi être obtenu de manière moins efficace avec d’autres agents solubles en milieu organique tels que le O-(Benzotriazol-1-yl)-N,N,N’,N’-tétraméthyluronium tétrafluoroborate et la triéthylamine (TBTU/TEA). Chaque étape menant aux CSPs a été caractérisée par une étude de flux électroosmotique (FEO) en OT-CEC. Des analyses en AFM et en MEB nous renseignent d’avantage sur le succès du procédé « etching » de nos capillaires. La deuxième grande partie de cette étude traite de la synthèse in-situ de CSPs sur des colonnes de type polymères monolithes organiques et un monolithe hybride à base de sol gel. Des post modifications de surface de ces supports monolithiques nous ont permis d’immobiliser de façon covalente et non covalente des sélecteurs de β-CD en surface des volumes macroporeux. Deux collaborations ont vu le jour pour atteindre ces objectifs. La première eut lieu avec le Dr Thuy Tran et le Pr Myriam Taverna de la Faculté de Pharmacie de Chatenay Malabry (UMR 8612), durant laquelle nous avons reproduit une colonne monolithe organique de type méthacrylate, porteuse de groupements phosphate dans l’optique d’adsorber physiquement en surface le polymère cationique de CDs (p-CD+) que nous a transféré le Pr Benjamin Carbonnier et d’évaluer les capacités de discrimination chirale de cette nouvelle CSP en m-CEC. La seconde collaboration a eu lieu avec le Dr Mohamed Guerrouache et le Pr Benjamin Carbonnier au sein du laboratoire ICMPE de Thiais, où nous avons synthétisé des colonnes monolithiques organiques à base d’acrylates dans le but de greffer en surface de façon covalente et non covalente les CDs et polymères de CDs et d’évaluer ces nouvelles CSPs en m-CEC. La troisième phase stationnaire monolithique employée est celle décrite par le Dr Huihui Yang qui décrit un monolithe hybride porteur de groupements sulfonates nous permettant par la suite d’immobiliser électrostatiquement le p-CD+ sur le réseau poreux et d’évaluer cette nouvelle CSP en m-CEC. / New chiral stationary phases have been prepared for Open Tubular and monolithic columns used in electrochromatography capillary. In order to separate racemic mixtures such as flavonoïd, Hidantoïn derivatives, Binaphtalene-2, 2-hydrogenophosphate and others chiral solutes, we use the β-cyclodextrin forms as chiral selector. Besides, β-cyclodextrin seems to be the most efficient chiral selector in chromatography since it is able to complex and dissolve optical organic isomers in an aqueous media, this chiral selector is able to dissolve even lipophilic molecule with high weight. The complexation is based on interactions with β-cyclodextrin. This study aims to elaborate new chiral stationary phase for CEC using β-cyclodextrin polymers and β-cyclodextrin derivatives. Two approaches were used: Firstly, covalent stationary phases coating with carboxymethyl-β-cyclodextrin polymers and oligomers containing carboxyl’s group had been experimented for open tubular and monolithic column in CEC. Then a non-covalent coating cationic polymer of β-cyclodextrin’s derivatives was immobilized (polytrimethyl ammonium β-CD) on continuous organic monoliths bearing anionic’s group. Prior to the covalent coating of the CD’s chiral selector for OT-CEC and m-CEC, we needed to modify the silicate surface and the monolithic surface with a primary amine silicate1,2 (aminopropyltriethoxysilane) and EDA, an amino-organic moiety (Ethylene diamine). The stability of the bonded organic moiety (APTEOS, EDA) were studied by CEC at different pH with constant ionic strength’s buffer. In this way, graft of carboxymethyl-β-cyclodextrin polymer on silica inner surface modified by APTEOS and on NAS-co-EDMA surface modified by EDA succeeded in activating and covalently coupling reagent as EDC and NHS (1-ethyl-3(-3-dimethtylaminopropyl) carbodiimide and N-hydroxysuccinimide, respectively3) with carboxymethyl’s group of carboxymethyl-β-cyclodextrin . The resultant stationary phase lead to stable chiral stationary phases, easier to prepare starting by coupling the selector to the amine’s group using EDC and NHS. In order to optimize enantio-separations by increasing the specific surface of open tubular columns, we reproduce the etching process to bared capillaries with ammonium bifluoride solution, referred to Pesek’s process4. By this mean, we increase dramatically the specific surface of bared capillaries before anchoring CDs polymers to silicate surfaces modified by APTEOS. Finally due to etching process, we obtain a covalent bonded Chiral Stationary Phase (CSP) which led to more efficient and resolvent enantio-separations by CEC. To describe, in another way, the non-covalent coating of CSP, we immobilised a cationic polymer (polytrimethyl ammonium β-CD+) on two kind of continuous organic and silica hybrid monoliths bearing sulfonate5 and phosphate’s groups. Based on precedent results for OT-CEC enantio-separation with LbL stationary phase7, using successive layers charged polymers to separate racemic mixture in CEC, we decided to adsorb a polycationic polymer hydrosoluble onto the silica hybrid monolith column to form chiral stationary phase (CSP) polytrimethyl ammonium β-cyclodextrin. This way of modification for monolithic surface by chiral selectors is nowadays highly efficient and attractive for CEC. The effect of the matrix and the coating’s nature are discussed by comparing the chromatographic parameters.
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Príprava realizácie polyfunkčných domov v Bratislave / Preparation for the implementation of the multifunctional buildings in BratislavaJaníček, Peter January 2022 (has links)
This diploma thesis deals with the preparation of the implementation of multifunctional buildings in Bratislava. These are three detached multi-storey apartment buildings connected by a joint basement. The diploma thesis includes a technical report to the construction technological project, a study of the implementation of main technological phases, solving of broader relations of transport routes with the design of supply routes, a time schedule and a financial plan of the object, a detailed time plan for the rough substructure and rough superstructure, a building site equipment project, a machine assembly design and its assessment, a technological regulation for monolithic structures, a control plan and test plan for monolithic structures, a specification of the time period of the removal of the formwork of monolithic structures, an occupational safety and health plan and selected points of the LEED certification. The thesis also includes a plan for securing resources for the rough structure with added schedules of workers, machines and building materials, a cost estimation budget of selected technological processes, a noise study, and a financial analysis of the expected investment profit.
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Design & Fabrication of Microfluidic DNA Extraction Device for Water Quality MonitoringDang, Bo 10 1900 (has links)
<p>Continuous monitoring of pathogens that may be present in water is one of the key preventive measures that can be used in rural areas of developed countries and developing countries to reduce chances of the water borne diseases outbreak. Off-site testing of microbiological contamination of water is conventionally done for monitoring water quality. However, such a process is time consuming and involves using a variety of hazardous reagents. To address these issues, a portable device for rapid detection of unsafe water is needed.</p> <p>One of the key components in this system is to extract DNA from the pathogens. The primary consideration for DNA extraction is to separate DNA from proteins and other cell debris in the lysate solution. The pure population of DNA molecules are then sent downstream for subsequent processing such as real-time PCR (Polymerase Chain Reaction) and BioFET sensors for further identification and analysis.</p> <p>The focus of the thesis will be on the fabrication of a microfluidic DNA extraction system that can achieve high DNA extraction efficiency and a good repeatability. It can also be easily automated, and integrated with other components of the DNA analysis system. The high surface-to-volume macro/mesoporous silica DNA binding column was synthesized using sol-gel silica technology and triblock copolymer F127 was added to form a crack-free mesoporous silica network. Furthermore, a monodispersed polystyrene microspheres soft-template was assembled using a simple but novel technique that employs controlled suction to enhance self-assembly into a periodically patterned structure in the extraction chamber/chambers. In combination of heat annealing treatment of this assembled polystyrene template, one can easily control the size of the macropores in the final macro/mesoporous silica structure to allow a lower pressure resistance for DNA sample flow at elution stage. The final macro/mesoporous silica structure synthesized using heat annealing temperature of 115<sup>o</sup>C for 10 minutes was determined to have a porosity of 83.6%. Mesopores of this silica monolith was determined by BET test to be 3.65 nm and the macroporous ranging from 0.5μm to 0.86μm were observed. In addition, the fabrication of porous silica monolith can be easily integrated with the microfluidic system for achieving DNA extraction purposes</p> / Master of Applied Science (MASc)
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Realizace bytového domu pro sociální bydlení ve Starči - stavebně technologický projekt / Implementation of Apartment House for Social Housing in Starec - Building Contruction ProjectBobek, Vojtěch Unknown Date (has links)
Master thesis focuses on complex conducting of the technological project with accented earthwork, laying foundations and ceiling construction. Apartment building consists of two floors and is based in complicated geotechnical conditions which require changing subsoil and laying a foundation slab. The main aim of this thesis is a proposal of technological notes, time and financial management, selection of machinery, transport to the building site, work safety regulations, quality check of the conducted work and construction organisation.
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