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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.
41

Aplikace mesalazinu do peritoneální dutiny potkana

Hönigová, Kateřina January 2019 (has links)
The objective of this diploma thesis was to determine the influence of the application of 5-aminosalicylic acid (5-ASA) in the peritoneal cavity on the initiation and course of the inflammatory reaction. For these purposes, the rat was chosen as the model animal on which the model of intraperitoneal lavage was applied. The rat’s peritoneal cavity is easily accessible and reflects the functions and reactions of the immune system. For the purposes of the experiment, the rats were divided into 3 groups; in the first group, the peritoneal cavity was assessed in its physiological condition, without any prior application of the substance. PBS was applied to the second group of rats, and the evaluation of the absolute numbers of cells followed after 4 and 24 hours using the Bürker counting chamber and optical microscopy. In the last group, mesalazine was applied, the exposure of which was 4 hours for one half of the group and 24 hours for the other. These time intervals were followed by the evaluation of the absolute number of cells. In order to determine the differential numbers of cells for all the samples, the coated glasses were coloured and evaluated. The greatest statistically relevant difference was identified in the case of the neutrophil population, where the neutrophil share increased from 0-5 % in the intact cavity to up to 35 % in the cavity after the PBS application. Out of all the experimental groups, the population of lymphocytes was relatively stable; the share of macrophages was, statistically, considerably lower for the groups after the mesalazine application. These results indicate that the application of PBS as an inert substance did not cause such a major reaction regarding the influx of neutrophils as the application of 5-ASA.
42

Surface and Interface Effects on the Photoexcited Process of Silver Nanoclusters, and Lead & Cadmium Chalcogenide Nanocrystals

Jabed, Mohammed Abu January 2020 (has links)
The surface and interface of the metal nanoclusters and semiconducting nanomaterials play a key role in determining the electronic structure and overall photophysical properties. A single strand DNA stabilizes the metal nanoclusters, but it also influences the structural change, solvation free energy, and photophysical properties. On the other hand, surface and interface states in Pb and Cd chalcogenide nanomaterials affect the phonon mediated hot carrier relaxation. We applied DFT and DFT based non-adiabatic dynamics methods to study the surface and interface?s effects on the photoexcited processes. In the first part, we have studied the Ag nanoclusters' photophysical properties that are affected by the structural isomers, redox potential, nucleobase passivation, and cluster size. Ag nanoclusters are shown alternative reduction potential, which makes nanoclusters of singlet spin multiplicity thermodynamically favorable. Besides, the optically bright transition in the range of 2.5-3.5 eV is shown metal to ligand charge transfer. It is modulated by the s+p+d orbital mixing in the hole and electron states. We also simulate the charge transfer from the photoexcited PbS QD to organic dye (PDI) attached to the QD surface. Depending on the linker group and the dipole moment of neighboring passivating ligands, the PDI-QD conformations are varies. In response to structural change, the total dipole moment is modulated, changing its electronic structure and hence the photoexcited electron transfer rate from the PbS QD to PDI. We also investigate the inorganic-inorganic interactions in the PbCl2 bridged PbSe NPL and PbSe|CdSe Janus heterostructure. The energy dissipation rate of hot electrons is slower in NPL than the hot hole, while hot e-h relaxed to the band-edge by ?1.0ps in the QD. The slower relaxation rate is rationalized by a large average intraband energy difference and smaller coupling term. Besides, the hot carriers in the NPL are spatially separated by ?1.00 ps, which is a favorable condition for the carrier multiplication process. In Janus QD, (100) interfacial layer creates a structural mismatch in the CdSe part. Besides, the energy offset between the valance localized on PbSe and CdSe part is minimum in the PbSe Janus QD of an interface of (111) facet.
43

Manufacturing optimization and film stability analysis of PbS quantum dot solar cells / Tillverkningsoptimering och filmstabilitetsanalys av PbS kvantprickssolceller

Bryngelsson, Erik January 2019 (has links)
Semiconductor colloidal quantum dots have an interesting potential to increase solar cell efficiency, with strong absorption in the infrared region and a tunable band gap. In this work an attempt was made to adopt a manufacturing process for PbS quantum dot solar cells, proven successful at Uppsala University. Two optimizations were investigated and the stability of the quantum dot films was analyzed with regards to three storage conditions, varying oxygen accessibility and light exposure, and measured with UV-Vis spectroscopy and X-ray photoelectron spectroscopy. Functioning solar cells were obtained but with lower performance than the results from Uppsala. Optimizations were partly successful with regards to improved spreading of the EDT solution on the PbS quantum dot film using ethanol and methanol as solvents. No improved cell performance was observed by applying both QD films inside argon atmosphere, as opposed to only the first one. Clear differences in oxidization of the films and loss of iodine ligand could be identified for the different storage conditions, with best stability exhibited by films stored under argon atmosphere. / Kvantprickar av halvledande material har en intressant potential att förbättra solcellers verkningsgrad genom en stark absorption inom de infraröda spektrat och ett justerbart bandgap. I detta arbete gjordes ett försök att återskapa en tillverkningsprocess av kvantprickssolceller av PbS, som visat sig framgångsrik vid Uppsala universitet. Två optimeringar undersöktes och stabiliteten av kvantpricksfilmerna analyserades med avseende på tre förvaringsmiljöer med olika exponering för ljus och syre, och mättes med UV-visspektroskopi samt röntgenfotoelektronspektroskopi. Fullt fungerande solceller framställdes men med en lägre prestanda jämfört med resultaten i Uppsala. Optimeringarna var delvis lyckade gällande spridning av EDTlösningen på kvantpricksfilmen av PbS genom att använda etanol och metanol som lösningsmedel. Ingen förbättrad prestanda observerades hos cellerna genom att applicera båda kvantpricksfilmerna i argonatmosfär, jämfört med endast den första. Tydliga skillnader i oxidation för filmerna samt förluster av jodligand kunde identifieras för de olika förvaringsmiljöerna, med bäst stabilitet uppvisad av filmerna som förvarades i argonatmosfär.
44

Состав, структура, функциональные свойства пленок твердых растворов CdxPb1-xS, химически осажденных с использованием галогенидов кадмия : автореферат диссертации на соискание ученой степени кандидата химических наук : 1.4.4

Селянина, А. Д. January 2023 (has links)
No description available.
45

Состав, структура, функциональные свойства пленок твердых растворов CdxPb1-xS, химически осажденных с использованием галогенидов кадмия : диссертация на соискание ученой степени кандидата химических наук : 1.4.4

Селянина, А. Д. January 2023 (has links)
No description available.
46

Development and Characterization of Experimental Autoimmune Cystitis (EAC)

Izgi, Kenan 19 June 2012 (has links)
No description available.
47

Synthesis and AB-Initio Simulations of Colloidal PBS Nanosheets

Bhandari, Ghadendra B. 16 July 2014 (has links)
No description available.
48

Exciton Diffusion in Nanocrystal Solids

Kholmicheva, Natalia N. 02 August 2017 (has links)
No description available.
49

Morphology and Surface Passivation of Colloidal PbS Nanoribbons

Antu, Antara Debnath 02 August 2017 (has links)
No description available.
50

Optical and Electonic Characterization of PbS Quantum Dot Films

O'Dell, Ryan A. 19 December 2013 (has links)
No description available.

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