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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Stanovení vybraných fytofarmak a jejich metabolitů v odpadních vodách / Determination of selected phytopharmaceuticals and their metabolites in waste waters

Nevědělová, Klára January 2008 (has links)
This diploma thesis will be focused on the identification and quantification of selected phytopharmaceuticals ant theri transformation products using separation and spectrometric methods available in the laboratories of ICTEP.
12

Etude des propriétés de conduction et structurales des verres du système Hgl₂-Ag₂S-As₂S₃ : application en tant que capteur chimique / Study of conduction and structural properties of Hgl₂-Ag₂S-As₂S₃ glasses : applications as membrane of ionic selective electrode

Boidin, Rémi 22 October 2013 (has links)
Les verres du système binaire Ag₂S-As₂S₃ sont connus pour être de très bons conducteurs ioniques et l’ajout de HgI₂ permet d’envisager une application des verres du pseudo-ternaire HgI₂-Ag₂S-As₂S₃ en tant que membrane ionique spécifique dédiée au dosage du mercure en solution aqueuse. Les limites de son domaine vitreux ont été vérifiées à l’aide de la diffraction des rayons X. Les évolutions des propriétés macroscopiques des verres, incluant les densités et les températures caractéristiques (Tg, Tc et Tf) ont été analysées de façon systématique. Les propriétés de conduction des verres HgI₂-Ag₂S-As₂S₃ ont été évaluées à l’aide de la spectroscopie d’impédance complexe et de la diffusion du traceur radioactif 108mAg. Un des résultats les plus marquants dans ces verres conducteurs ioniques est l’augmentation de la conductivité lorsque Ag₂S est substitué par HgI₂. Afin de comprendre les mécanismes de conduction mis en jeu, des études structurales ont été menées par spectroscopie Raman, diffusion de neutrons et diffraction des rayons X haute énergie. Pour appréhender la structure de ces verres complexes, des études préalables sur les deux systèmes pseudo-binaires Ag₂S-As₂S₃ et HgI₂-As₂S₃ ont aussi été menées. Les différentes techniques utilisées ont notamment permis de montrer que des réactions d’échanges se produisaient lors de la synthèse. Enfin, la dernière partie de cette thèse est entièrement consacrée à la caractérisation de nouveaux capteurs chimiques pour la détection des ions Hg²+ en solution. Différentes compositions sont testées afin de définir la sensibilité, la limite de détection et les coefficients de sélectivité en présence d’ions interférents. / Glasses of the pseudo-binary system Ag₂S-As₂S₃ are well known to be good ionic conductors and the addition of HgI₂ allows considering the glasses of the pseudo-ternary system HgI₂-Ag₂S-As₂S₃ as ion-membrane dedicated to mercury sensing in aqueous solution. The limits of its vitreous domain were verified by X-ray diffraction. Changes in macroscopic properties of glasses, including density and characteristic temperatures (Tg, Tc et Tm) were systematically investigated. Conduction properties of HgI₂-Ag₂S-As₂S₃ glasses were evaluated using the complex impedance spectroscopy and 108mAg tracer diffusion measurements. One of the most interesting results concerns the conductivity increase if Ag₂S is substituted by HgI₂. To understand the conduction mechanisms involved, structural studies were carried out by Raman spectroscopy, neutron scattering and high-energy X-ray diffraction. To understand the structure of these complex glasses, preliminary studies on the two pseudo-binary systems Ag₂S-As₂S₃ and HgI₂-As₂S₃ were also undertaken. These techniques have underlined exchange reactions that occur during the synthesis. The last part of this research work is entirely devoted to the characterization of new chemical sensors for the detection of Hg²+ ions in solution. Different compositions were tested to determine the sensitivity, detection limit and selectivity coefficients in the presence of interfering ions.
13

Inside men : confession, masculinity, and form in American fiction since the Second World War

McMaster, Iain George January 2018 (has links)
This thesis examines the use of form and spatial language in confessional fiction by men to elucidate how they conceptualise and negotiate material, corporeal, and psychological boundaries amidst the shifting social and political landscape of the United States since the Second World War. In light of increasingly urgent calls to address gender and racial discrimination in the United States, this study offers timely insight into an identity that, while culturally dominant, often escapes examination: white, heterosexual masculinity. Focusing on the representation of forms and spatial imagery, the chapters explore how five formally experimental novelists-Vladimir Nabokov, Joseph McElroy, Harry Mathews, William H. Gass, and Peter Dimock- employ the confessional genre to illustrate the way men perceive themselves as spatially and temporally circumscribed, and to look at the way they reinforce or transgress the boundaries of masculine identity. The post-war period in the United States witnessed a proliferation of confessional writing that coincided with the popularisation of Freudian psychoanalysis, the cold war rhetoric of suspicion, and the rise of second-wave feminism. As a result, the concept of the self increasingly becomes a repository for fantasies of potential discovery and hidden danger that rely, significantly, on metaphors of surface and depth. It is within, and often against, this cultural preoccupation with the self that these writers address, both directly and indirectly, the status of white masculinity. Drawing on innovative theories of forms and spatiality, this study examines the diverse language and imagery men use to describe their sense of selfhood as well as the bonds they form with others. The works considered in this study demonstrate a common preoccupation with the boundaries that separate interior from exterior and private from public. In response to pressures both intimate and impersonal, the narrators of the texts discussed in this thesis turn to confessional practices of written self-examination to locate themselves within networks of fluctuating relations and obligations. The question that this thesis seeks to resolve is whether the forms and spatial language the narrators employ enable or obstruct their efforts to negotiate the competing demands of ethical responsibilities to others and the desire to preserve a stable sense of self.
14

Studium sterilizačních účinků dielektrického bariérového výboje / Study of Sterilization Effects Initiated by Dielectric Barriere Discharge

Slámová, Jitka January 2013 (has links)
The overall goal of the presented dissertation thesis was to study the sterilization efficiency of dielectric barrier discharge operated at atmospheric pressure. The fungi Aspergillus niger, gram-positive bacteria Bacillus subtilis and in some experiments also gram-negative bacteria Escherichia coli were used as a bio-indicator enabling to evaluate the effect of plasma assisted microbial inactivation. The samples of microorganism were placed on paper Whatman 1 or PET foil and exposed to plasma. The plasma was generated in argon, nitrogen, synthetic dry/humid air with frequency up to 10 kHz and plasma power density in the range of 1,2-2,9 W/cm3 (according to the process gas). The influence of process gas, plasma power density, plasma exposition time, type of microorganism and material of the substrate on the sterilization effect of dielectric barrier discharge was evaluated. Furthermore the contribution of each single mechanism (UV radiation, temperature and reactive species) to the sterilization effect of plasma and influence of gas humidity was evaluated. The DBD was analysed by means of optical emission spectroscopy, thermocouple was used to measure temperature during a sterilization process. In order to verify the mechanical damage of the microbial cell or the substrates during the plasma process the samples were studied by scanning electron microscopy. Generally, on the basis of experimental results, at increasing treatment times, the remaining number of spores (CFU) decreased. Similarly at increasing the plasma power input, the sterilization rate increased. When sterilising the spores of A. niger in plasma using different process gasses, the efficiency of plasma sterilization decreased as follows: argon, humid synthetic air, nitrogen and dry synthetic air. The results observed in argon plasma using different microorganism demonstrated that the sensitivity of vegetative cells resp. spores to DBD decreased as follows: A. niger spores, B. subtilis vegetative cells, E. coli vegetative cells and B. subtilis spores. Simultaneously results observed for sterilization of spores and vegetative cells of B. subtilis and A. niger demonstrated that the spores are generally more resistant to plasma than are the corresponding vegetative cells. Combining the results of contribution of each single mechanism, optical emission spectroscopy and inactivation characteristic it was found out that the reactive species significantly contribute to the plasma sterilization in all process gasses. Furthermore the inactivation process can be partly assisted by UV radiation and also the temperature can contribute in limited extent to inactivation process in some gasses. The contribution of UV radiation to the plasma sterilization decreased as follows: nitrogen, argon, dry syntetic air and humid syntetic air. Moreover it was found out that the contribution of each single mechanism can be species dependent, this is due to the different response of microorganism to the unfavorable external conditions. SEM analysis of the substrates prooved the etching actions of the plasma generated in all process gasses on the surface of the PET foil. The several minute plasma exposition of the PET foil resulted in the occurence of the „hole corrosion“ on the PET surface. Contrary to these there were no visible changes observed in the paper structure.
15

Silences et dissidences dans les journaux de l'expédition Lewis et Clark / Silence and Dissidence in the Lewis & Clark Expedition Journals

Atem, Florent 22 May 2015 (has links)
Intitulé « Silences et dissidences dans les journaux de l’expédition Lewis et Clark », notre travail, centré sur le voyage de découverte de Meriwether Lewis et William Clark, s’appuie sur un corpus de textes récemment publiés. Revenant sur la voix officielle du discours jeffersonien incarnée par les capitaines, mandataires d’une mission à visée autant géopolitique et économique que scientifique, notre recherche proposera une relecture des écrits du « Corps de la Découverte », ainsi qu’une tentative de réhabilitation des voix annexes, celles de sergents et de soldats de la troupe, généralement considérées comme secondaires et pourtant révélatrices de points de vue parallèles, essentiels à une mise en perspective historiographique nouvelle. Ce regard neuf sur un épisode crucial de l’histoire du continent et du peuple nord-américains tentera de démontrer qu’au-delà du témoignage des chefs, seule une prise en compte d’une symphonie narrative, où se mêlent voix « officielles » mais aussi « dissidentes », autorise une restitution pertinente du tissu narratif global. Plus de deux siècles après le périple transcontinental du groupe mené par Lewis et Clark, cette étude se propose donc de mettre en relation de façon systématique l’ensemble des manuscrits de l’expédition, pour une exploitation rénovée de ces sources primaires. La présente analyse des récits des explorateurs s’inscrit dans le contexte de la politique jeffersonienne, dont il sera utile de présenter certains concepts fondamentaux afin d’apprécier au mieux, au travers du prisme des différents témoignages, le caractère exceptionnel d’une épopée profondément « américaine ». / This study, entitled “Silence and Dissidence in the Lewis & Clark Expedition Journals,” focuses on the voyage of discovery under the command of Meriwether Lewis and William Clark, and draws upon a body of recently published texts. Reassessing the official voice of the Jeffersonian discourse, embodied by the captains in charge of a mission with geopolitical, economic and scientific purposes, our research aims at shedding new light on the writings of the Corps of Discovery, in an attempt to rehabilitate the somewhat neglected voices of the sergeants and soldiers of the group, often deemed secondary but actually indicative of alternate vantage points, allowing for new historiographical perspectives. This new reading of a critical episode in the history of the North American continent, as well as its people, will endeavour to show that, beyond the leaders’ reports, it is only through the symphony of intertwining “official” and “dissenting” voices that true relevance and accuracy may be achieved in the final synthetic narrative. More than two centuries after the transcontinental journey of the party led by Lewis and Clark, this study will aim at systematically interconnecting the whole set of manuscripts devoted to the narration of the voyage, for a better and renovated approach of these precious primary sources. This analysis is linked to the broader framework of the Jeffersonian policy, the main aspects of which shall first be presented, in order to fully grasp the exceptional nature of a profoundly “American” epic, through the prism of the various testimonies.
16

Prieskoninių augalų, eterinių aliejų sudėties tyrimas, panaudojant skirtingus ekstrakcijos metodus / Essential oils composition analysis in herbal spices using different extraction methods

Sinkevičius, Robertas 20 June 2012 (has links)
Augant pasaulinei pramonei aplinkos tarša nepaliaujamai didėja, tad augalai augantys užterštoje aplinkoje, savo sudėtyje taip pat turi nemažai įvairių junginių, kurie gali įtakoti juos vartojančių žmonių sveikatą. Eterinių aliejų išgautų iš augalų tyrimas yra vienas iš būdų nustatant augalo kokybę, užtikrinant, kad taršalai nepateks tolesniam perdirbimui. Eteriniams aliejams išgauti yra daug būdų, kaip kad distiliacija vandens garais, šviežių aromatinių dalių išspaudimas, ekstrakcija tirpikliais, tačiau tokie išgavos būdai būdingesni išgaunant didelius kiekius, tad reikia ir daug žaliavos. Tyrimams naudojami greitesni, bei mažiau žaliavos reikalaujantys metodai, kaip, kad ekstrakcija superkritiniais skysčiais, kietafazė mikroekstrakcija bei ekstrakcija iš bandinio viršerdvės. Šio darbo tikslas - eterinių aliejų, išgautų superkritinių skysčių ekstrakcijos, kietafazės mikroekstrakcijos bei tiesioginės viršerdvės ekstrakcijos būdais, sudėties nustatymas dujų chromatografijos – masių spektroskopijos metodu. Panaudojant gautus duomenis nustatyti kuris ekstrakcijos būdas pasižymi didžiausiu efektyvumu. Duomenų tikslumo užtikrinimui bandiniai pakartotinai leisti po 3 kartus, identifikuoti junginiai tikrinti skaičiuojant kovačo retencijos indeksus ir juos lyginant su jau žinomais indeksais internetinėje bibliotekoje. Darbo metu remiantis gautais duomenimis nustatyta efektyviausias eterinių aliejų ekstrakcijos metodas, junginiai, esantys bandiniuose bei būdingųjų junginių kiekis. / As the word industry develops, the amount of wastes, that are being released in to our environment is always increasing, as a result vegetables that are growing in such a environment are also contaminated with compounds that can affect the health of people that are using them. Many methods can be used to obtain essential oils, such as distillation using water vapour, extruding from fresh fragrant, extraction using solvents, but these kind of methods are used for getting large amounts of essential oils, so staple is used. For chemical analysis faster and less staple demanding methods are used, such as, super critical fluid extraction, solid phase micro extraction or direct head space extraction. The goal of this work is to determine the composition of essential oils and to estimate witch, super critical fluid extraction, solid phase micro extraction or direct head space extraction is the best for obtaining essential oils from spice herbs. In order to secure the precision of data each sample was analyzed three times, for correct compound identification kovach retention indexes were calculated and compared with the known ones on the internet library. Using the obtained data the most effective method foe essential oils obtaining was determined, also compound composition in samples and the amount of specific compounds were analyzed.
17

Between Artifice and Actuality: The Aesthetic and Ethical Metafiction of Vladimir Nabokov and David Mitchell

McDonald, Trent A. 14 May 2014 (has links)
No description available.

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