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Ionic Defects in Metal Halide Perovskite Solar CellsReichert, Sebastian 21 May 2021 (has links)
Solarzellen aus organisch-anorganischen hybriden Perowskithalbleitern gelten als mögliche Schlüsseltechnologie zur Erzeugung günstiger und umweltfreundlicher elektrischer Energie und somit als Meilenstein für die Energiewende. Um die weltweit stetig wachsende Nachfrage an elektrischer Energie zu decken, bedarf es Solarzellentechnologien, welche gleichzeitig eine hohe Effizienz nahe dem Shockley-Queisser-Limit als auch eine hinreichend gute Stabilität aufweisen. Während die Effizienz von Solarzellen auf Basis von Perowskithalbleitern in dem letzten Jahrzehnt eine bemerkenswerte Entwicklung erfahren hat, lassen sich die wesentlichen physikalischen Mechanismen dieser Technologie noch nicht vollständig erklären. Die elektronisch-ionische Mischleitfähigkeit ist eine dieser Eigenschaften, welche die Effizienz und besonders die Stabilität der Perowskit-Solarzelle beeinflusst. Zentrales Thema dieser Arbeit ist daher die Untersuchung von mobilen ionischen Defekten und deren Einfluss auf Solarzellenparametern. Es wird gezeigt, dass die Migrationsraten ionischer Defekte in Perowskit breiten Verteilungen unterliegen. Durch die Anwendung eines neu entwickelten Regularisationsalgorithmus für inverse Laplace-Transformationen und verschiedener Messmoden für transiente Störstellenspektroskopie kann somit geklärt werden, warum sich berichtete ionische Defektparameter aus der Literatur für gleiche Defekte stark unterscheiden können. Dieses grundlegende Verständnis kann angewendet werden, um den Einfluss von kleinen stöchiometrischen Variationen auf die Defektlandschaft zu untersuchen und das Zusammenspiel zwischen elektronischen und ionischen Eigenschaften besser zu verstehen. Der Einsatz der Meyer-Neldel Regel ermöglicht ferner eine Kategorisierung ionischer Defekte in Perowskithalbleitern. Im letzten Teil dieser Arbeit wird gezeigt, dass elektrische und optische Methoden wie intensitätsmodulierte Spektroskopie geeignet sind, um Informationen über mobile Ionen in hybriden Perowskiten zu erhalten. Zusätzlich wird das elektronische Rekombinationsverhalten näher untersucht. / Solar cells made of organic–inorganic hybrid perovskite semiconductors are considered as a possible key technology for the conversion of cheap and environmentally
friendly electrical energy and thus as a milestone for the turnaround in energy policy. In order to meet the steadily growing global demand for electrical energy, solar cell tech-
nologies are required that are both highly efficient, i.e. close to the Shockley–Queisser limit, and sufficiently stable. While the efficiency of solar cells based on perovskite semi-
conductors has undergone a remarkable development in the last decade, the essential physical mechanisms of this technology cannot yet be fully explained. The electronic-
ionic mixed conductivity is one of these properties, which influences the efficiency and especially the stability of the perovskite solar cell. The central topic of this thesis
is therefore the investigation of mobile ionic defects and their influence on solar cell parameters. It is shown that the migration rates of ionic defects in perovskites are
attributed to wide distributions. By application of a newly developed regularisation algorithm for inverse Laplace transform and different measurement modes for deep-level
transient spectroscopy, it can thus be clarified why reported ionic defect parameters from the literature for the same defects can differ significantly. This basic understanding can
be used to study the influence of small stoichiometric variations on the defect landscape and to better understand the interaction between electronic and ionic properties. Us-
ing the Meyer–Neldel rule also allows the characterisation of ionic defects in perovskite semiconductors. The last part of this thesis shows that electrical and optical methods
such as intensity-modulated spectroscopy are suitable for obtaining information about mobile ions in hybrid perovskites. In addition, the electronic recombination behaviour
is examined more closely.
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Příspěvek k radiodiagnostice a k léčbě vybraných patologických lézí femuru v dětském a dospělém věku / Contribution to radiodiagnostics and to treatment of chosen pathological lesions of femur in childhood and in adultsHorák, Martin January 2014 (has links)
7 Abstract (AJ) Introduction Radiology examination using specialized modern imaging methods, including CT and MRI, is essential in the diagnosis of congenital and acquired diseases of the musculoskeletal system. The first part of the dissertation deals with certain congenital defects of the short femur, known in the literature as proximal femoral focal deficiency (PFFD). This part summarizes our experience with the radiological findings in the preoperative and postoperative period, with the main attention to the vascular supply to the affected area. The second part of the presentation deals with some aspects of autologous chondrocyte transplantation fixed at two different carriers implanted into post-traumatic articular cartilage defects of the distal femur. Radiological findings are evaluated in the relation to the histopathological findings. Objectives The first part of the study after the distribution of patients with PFFD by current commonly used radiographic classification sets the objective in the extent of scans of the hip joints to specify diagnosis PFFD in each patient and to evaluate in detail changes in the area of disability, especially a course of blood vessels. The evaluation of the radiation burden of repeated X-ray measurements was done with respect to the age of the patients. Tissue samples...
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Současné metody analýzy genomu a jejich využití v hledání genetických příčin nemocí / Current methods of genome analysis and their use in identification of genetic determinants of human diseasesStránecký, Viktor January 2015 (has links)
The study of rare genetic diseases presents unique opportunity to uncover the genetic and molecular basis of human traits and greatly helped to the identification of genes, to the elucidation of their function and to the characterization of metabolic pathways and cellular processes. Over the past decades, linkage analysis has been appropriate approach to search for the genes causing Mendelian diseases and contributed to the identification of many genes, but the genetic cause of many diseases remains unknown. New methods of studying the human genome, microarray technology and massively parallel sequencing (next generation sequencing), represent a way to efficiently identify the cause of genetically determined diseases, based on direct observation of mutations in the genome of affected individuals. These techniques replaced the traditional method of disease gene identification represented by linkage analysis and sequencing of candidate genes and have become the standard approach to elucidate the molecular basis of diseases. In this work, i describe the the results achieved by using these methods - identification of the genes underlying mucopolysacharidosis type IIIC, isolated defect of ATP synthase, Rotor syndrome, autosomal dominat ANCL and GAPO syndrome.
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