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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.
81

Role makrofágů v interakci leishmanie - flebotomus - hostitel / Macrophages in leishmania - sand fly - host interaction

Kratochvílová, Tereza January 2012 (has links)
Sand flies (order Diptera) are vectors of Leishmania parasites (Trypanosomatida), which are inoculated into the host skin together with the vector saliva. Sand fly saliva plays the important role in the Leishmania transmission; in naive host it supresses the host immune response assisting Leishmania to establish the infection, while in repeatedly bitten host it elicits a protective immune response. The submitted thesis focuses on the effect of sand fly saliva on macrophages, the key cells in the infection control. In the first part of the thesis we established a laboratory model L. major - P. papatasi - Balb/c to describe the protective effect of saliva immunization on Leishmania infection development. Immunized mice were protected against Leishmania infection which was reflected in the ear lesion size, parasite load in the ear dermis and draining lymph nodes but also in cytokine production. On the contrary, produced lower amount of nitric oxide, while arginase activity was comparable with nonimmunized group. The IgG antibodies against saliva served as a marker of exposure to sandflies while IgG antibodies against Leishmania antigens served as a marker of infection severity. The experiments were aimed on the possibility of cross-protectivity in Balb/c mice against L. major between closely related...
82

Die Bildung nichtoxidischer Sauerstoffphasen an Ru(0001)

Blume, Raoul 05 August 2005 (has links)
In dieser Arbeit wurde die Bildung nichtoxidischer Sauerstoffphasen an der Ru(0001)-Oberfläche untersucht. Glatte und defektreiche Oberflächen wurden einem hohen Sauerstoffdruck (bis 1bar) bei moderaten Temperaturen ( / The aim of the thesis presented here was the investigation of the formation of non oxidic oxygen phases on the Ru(0001) surface. Smooth and defect rich surfaces were exposed to high oxygen pressures (up to 1bar) at moderate temperatures (
83

Blendas à base de quitosana e poliacrilamida revestidas com ZnO como catalisadores para a fotodegradação do azul de metileno / ZnO coated chitosan and polyacrylamide based blends as catalysts for methylene blue photodegradation

MAIA, Luziane Freire 31 August 2017 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-10-11T20:17:54Z No. of bitstreams: 1 LuzianeMaia.pdf: 1947184 bytes, checksum: 04546b4f76a70fff92d57b9fee584431 (MD5) / Made available in DSpace on 2017-10-11T20:17:54Z (GMT). No. of bitstreams: 1 LuzianeMaia.pdf: 1947184 bytes, checksum: 04546b4f76a70fff92d57b9fee584431 (MD5) Previous issue date: 2017-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Textile dyes are recognized as a serious environmental problem due the huge quantity discharged annually in water environments, and its dangerous health risks. Efficient and low cost methods for effluent treatment and recovery of impacted areas are necessary and increasingly researched. The photocatalytic degradation is one of these methods, and this work investigated the feasibility of photocatalytic degradation of the methylene blue (AM) dye from aqueous solutions (5 and 15 mgL-1) in the presence and absence of prepared catalysts (chitosanpolyacrylamide (QT-P), and chitosan-polyacrylamide doped with Zn, QT-P/ZnO). The chitosan and polyacrylamide interaction was studied as a function of the degree of deacetylation of chitosan (64, 82 and 90%), previously obtained from the deacetylation of chitin extracted from shrimp exoskeletons. The QT-P/ZnO heterostructures were characterized by FTIR, XRD and MEV. The photocatalysis experiments were performed considering the effects of pH, contact time and mass variation. AM samples were irradiated with mercury vapor lamp (black light,50W mm-2) and photocatalysis was monitored by UV-Vis spectrophotometry, at the peak wavelength of 665 nm. The results indicated that QT-P interaction is favored by deacetylation. All the materials prepared showed a catalytic effect, but the heteroestructure obtained from the chitosan with the highest degree of deacetylation (QTC-P/ZnO) was the most efficient: 99.2% (AM, 15 mg L-1, 50 min) and 99.8% (AM, 5 mg L-1, 20 min). / Corantes têxteis são reconhecidamente um problema ambiental, não apenas devido a quantidade enorme despejada anualmente em ambientes hídricos, mas também pelos riscos que representam à vida, em virtude da sua natureza química. Métodos eficientes e de baixo custo para o tratamento de efluentes e recuperação de áreas impactadas são necessários e cada vez mais pesquisados. Entre tais métodos, investigou-se a viabilidade da degradação fotocatalítica do corante Azul de Metileno (AM), a partir de soluções aquosas (5 e 15 mgL-1), na presença e ausência de catalisadores preparados à base de quitosana-poliacrilamida (QT-P), dopados com Zn (QT-P/ZnO). A interação quitosana e poliacrilamida foi estudada em função do grau de desacetilação da quitosana (64, 82 e 90%), previamente obtidas a partir da desacetilação da quitina extraída de exoesqueletos de camarão. As heteroestruturas QT-P/ZnO foram caracterizadas por FTIR, XRD e MEV. Os experimentos de fotocatálise foram realizados considerando os efeitos do pH, do tempo de contato e da variação da massa. As amostras de AM foram irradiadas com lâmpada de vapor de mercúrio (luz negra, 50W mm-2) e a fotocatálise foi monitorada por espectrofotometria UV-Vis, no comprimento de onda de 665 nm. Os resultados indicaram que a interação QT-P é favorecida pela desacetilação. Todos os materiais preparados apresentaram efeito catalítico, porém a heteroestrutura obtida a partir da quitosana com maior grau de desacetilação (QTC-P/ZnO) foi a mais eficiente: 99,2% (AM, 15 mg L-1, 50 min) e 99,8 % (AM, 5 mg L-1, 20 min).
84

Vliv hygienicky ošetřené vody na srdeční frekvenci raka a jejich následnou mortalitu

MALINOVSKA, Viktoriia January 2018 (has links)
The study is focused on the evaluation of crayfish physiological reaction on hygienically treated water with chlorine dioxide (ClO2). A patented non-invasive monitoring system was used for observation of crayfish cardiac and locomotor activity. Monitoring was conducted from February to August 2017 under conditions of private commercial enterprise "Pivovar Protivín" in Czech Republic. Adult individuals of signal crayfish, Pacifastacus leniusculus, were kept separately in water-flow aquariums directly after the water treatment device producing ClO2 in concentration from 0.01 to 0.29 mg.l-1. Observed crayfish response to the disinfectant varied among individuals which could be explained by a different functional state and individual reaction on stimuli. Diurnal rhythm of some crayfish was disturbed even at a lower concentrations of chlorine dioxide (0.01-0.2 mg.l-1), while higher concentrations affected all animals. In addition to that, higher levels of chlorine dioxide ( 0.2 mg.l-1) significantly increased mortality. Maximum concentrations (0.2-0.29 mg.l-1) were observed 28 times in total during 202 days of monitoring, which resulted in 25 mortality cases occurred several days after exposure. In average, mortality of crayfish occurred three-four weeks after stocking to the experimental system. Possible lethal concentration of ClO2, which caused animal mortality, is 0.2 mg.l-1. Results suggested that crayfish exposure to ClO2, obviously, negatively affect their physiological processes; however, further studies are needed to examine specific effects of chlorine dioxide on internal organs of crayfish.
85

Nonaqueous synthesis of metal oxide nanoparticles and their assembly into mesoporous materials

Ba, Jianhua January 2006 (has links)
This thesis mainly consist of two parts, the synthesis of several kinds of technologically interesting crystalline metal oxide nanoparticles via nonaqueous sol-gel process and the formation of mesoporous metal oxides using some of these nanoparticles as building blocks via evaporation induced self-assembly (EISA) technique. <br> In the first part, the experimental procedures and characterization results of successful syntheses of crystalline tin oxide and tin doped indium oxide (ITO) nanoparticles are reported. SnO2 nanoparticles exhibit monodisperse particle size (3.5 nm in average), high crystallinity and particularly high dispersibility in THF, which enable them to become the ideal particulate precursor for the formation of mesoporous SnO2. ITO nanoparticles possess uniform particle morphology, narrow particle size distribution (5-10 nm), high crystallinity as well as high electrical conductivity. <br> The synthesis approaches and characterization of various mesoporous metal oxides, including TiO2, SnO2, mixture of CeO2 and TiO2, mixture of BaTiO3 and SnO2, are reported in the second part of this thesis. Mesoporous TiO2 and SnO2 are presented as highlights of this part. Mesoporous TiO2 was produced in the forms of both films and bulk material. In the case of mesoporous SnO2, the study was focused on the high order of the porous structure. All these mesoporous metal oxides show high crystallinity, high surface area and rather monodisperse pore sizes, which demonstrate the validity of EISA process and the usage of preformed crystalline nanoparticles as nanobuilding blocks (NBBs) to produce mesoporous metal oxides. / Diese Arbeit besteht hauptsächlich aus zwei Teilen. Der erste Teil befasst sich mit der Synthese von mehreren technologisch wichtigen, kristallinen Metalloxid-Nanopartikeln mittels nichtwässriger Sol-Gel Chemie. Der zweite Teil beinhaltet die Herstellung von mesoporösen Metalloxiden. Dabei wurden ausgewählte Nanopartikel als Bausteine verwendet und durch langsames Verdampfen des Lösungsmittels in die entsprechenden porösen Strukturen überführt. <br> Das experimentelle Vorgehen wie auch die Charakterisierung der erfolgreich hergestellten Zinnoxid- und Indiumzinnoxid-Nanopartikel sind im ersten Teil beschrieben. Die Zinnoxid-Nanpartikel zeichnen sich durch einheitliche Partikelgrösse (im Durchschnitt ca. 3.5 nm), hoher Kristallinität, und guter Dispergierbarkeit in Tetrahydrofuran aus. Diese Eigenschaften machen aus den Zinnoxid-Nanopartikeln die perfekten Bausteine für den Aufbau von mesoporösem Zinnoxid. Die Indiumzinnoxid-Nanopartikel haben eine einheitliche Partikelform, eine schmale Grösseverteilung (5-10 nm), hohe Kristallinität wie auch gute elektrische Leitfähigkeit. <br> Die Synthese und Charakterisierung von verschiedenen mesoporösen Metalloxiden wie TiO2, SnO2, Mischungen von CeO2 und TiO2, wie auch Mischungen von BaTiO3 und SnO2 werden im zweiten Teil der Arbeit diskutiert. Mesoporöses TiO2 und SnO2 werden als besonders gelungene Beispiele herausgehoben. Mesoporöses TiO2 wurde in Form von Dünnfilmen wie auch als Bulkmaterial hergestellt. Im Falle von SnO2 galt das Augenmerk vor allem der hohen Ordnung der Mesoporen. Alle diese mesoporösen Materialien zeigen eine hohe Kristallinität, grosse Oberfläche und relativ einheitliche Porengrössen. Diese Eigenschaften unterstreichen, wie wertvoll der Ansatz ist, vorgeformte Nanopartikel als Bausteine für die Synthese von porösen Materialien zu verwenden.
86

Röntgenografische Charakterisierung von Indium-Zinn-Oxid-Dünnschichten

Kaune, Gunar 07 January 2006 (has links) (PDF)
Mittels reaktivem Magnetron-Sputtern hergestellte Indium-Zinn-Oxid-Dünnschichten wurden mit den Methoden der Röntgendiffraktometrie und Röntgenreflektometrie charakterisiert. Es konnte gezeigt werden, dass die Wahl des Arbeitspunktes bei der Schichtabscheidung erheblichen Einfluss auf Kristallitorientierung, Gitterkonstante und Größe der Schichtspannung hat. Zusätzlich wurden mittels des Langford-Verfahrens Korngröße und Mikrospannungen bestimmt. Im Rahmen der röntgenografischen Spannungsmessung zeigten sich nichtlineare Verläufe der Dehnung über sin²Ψ, die mit dem Kornwechselwirkungsmodell nach Vook und Witt erklärt werden.
87

Untersuchungen zum Cross-Magnetron-Effekt bei der reaktiven Indium-Zinnoxid-Abscheidung

Kleinhempel, Ronny 22 August 2008 (has links) (PDF)
In der vorliegenden Arbeit wird der reaktive ITO-Abscheidprozess unter Verwendung metallischer In:Sn-Targets eingehend untersucht. Die Schichtabscheidung erfolgt am symmetrisch bipolar gepulstem Dual-Magnetron sowohl auf ruhende als auch bewegte Substrate. Die Arbeit umfasst zwei Teilgebiete. Einerseits wurde der dynamische ITO-Abscheideprozess an einer industrienahen Versuchsanlage umfassend charakterisiert und anhand seiner physikalischen Parameter erfolgreich an eine industrielle Beschichtungsanlage überführt. Andererseits fanden statische Beschichtungen statt. Diese ermöglichen die Analyse der lateralen Verteilung der funktionellen Schichteigenschaften. Dadurch konnte eine Korrelation zu den lateralen Verteilungen der gemessenen Plasmaparameter herausgearbeitet werden.
88

Dielectric tensor of monoclinic Ga2O3 single crystals in the spectral range 0.5–8.5 eV

Sturm, Chris, Furthmüller, Jürgen, Bechstedt, Friedhelm, Schmidt-Grund, Rüdiger, Grundmann, Marius 20 November 2015 (has links) (PDF)
The dielectric tensor of Ga2O3 in the monoclinic (β) phasewas determined by generalized spectroscopic ellipsometry in a wide spectral range from 0.5 eV to 8.5 eV as well as by density functional theory calculations combined with many-body perturbation theory including quasiparticle and excitonic effects. The dielectric tensors obtained by both methods are in excellent agreement with each other and the observed transitions in the dielectric function are assigned to the corresponding valence bands. It is shown that the off-diagonal element of the dielectric tensor reaches values up to |εxz| ≈ 0.30 and cannot be neglected. Even in the transparent spectral range where it is quite small (|εxz| < 0.02) it causes a rotation of the dielectric axes around the symmetry axis of up to 20◦.
89

CMOS-Prozessintegration von epitaktischen Selten-Erden-Oxiden als high-K-Dielektrika auf SOI-Substraten

Gottlob, Heinrich Dieter Bernd January 2007 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss., 2007
90

Entwicklung und Charakterisierung von lasertransformierbaren Schichten auf Basis von Indiumzinnoxid /

Neubert, Thomas. January 2007 (has links) (PDF)
Techn. Univ., Diss.--Braunschweig, 2007.

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