Die Elemente Al, Mg und Zn sind wichtige Komponenten für leichte und hochfeste Legierungen, wie die Al- oder Mg-Knetlegierungen. Darüber hinaus ist das Al-Mg-Zn-System sehr interessant, weil vier ternäre komplexe intermetallische Phasen, genannt τ1, τ2, Φ und q, darin vorkommen. Die aktuellen experimentellen Phasendiagramme des Al-Mg-Zn-Systems enthalten nur provisorische oder keine Homogenitätsbereiche der Φ-, τ2- und der q-Phase aufgrund unzureichender experimenteller Daten. Ziel der Arbeiten war es, die Homogenitätsbereiche der q-, τ2- und der Φ-Phase neu zu ermitteln und die Kristallstruktur der Φ-Phase zu bestimmen. Proben wurden durch Schmelzen und Wärmebehandlung in Ta-Ampullen oder durch Zentrifugieren aus der Schmelze hergestellt und durch XRD, SEM, EDXS, WDXS und DSC charakterisiert. Während der Neuuntersuchung der Al-Mg-Zn Phasengleichgewichte in der Nähe des Teilsystems Mg-Zn und nahe bei τ1 wurde eine Reihe von neuen ternären Phasen entdeckt. Die Kristallstrukturen für die Φ-Phase (Pbcm, a = 8,9374 (2) Å, b = 16,812 (3) Å, c = 19,586 (4) a) und drei der neuen intermetallischen Verbindungen wurden gelöst und die Kristallstruktur des τ2 Phase wurde erneut untersucht. Während τ2 (Pa-3, a = 23,034 (3) Å) ein Approximant der ikosaedrischen quasikristallinen Phase q ist, erwies sich eine der neuen Phasen (τd, Imm2, a = 5,2546 (2), b = 40,240 (2), c = 25,669 (1) Å) als dekagonaler Approximant. Überraschenderweise wurde eine Phase (Fd-3m, a = 27,5937 (9) Å) gefunden, die isotyp zu der binären Phase β-Al3Mg2 ist, aber eine Zn-reiche Zusammensetzung hat.:1 Einleitung 1 2 Grundlagen 5 2.1 Frank-Kasper-Phasen und tetraedrisch dicht gepackte Strukturen 5 2.2 Parkettierungen, Quasikristalle and Approximanten 11 2.3 Phasendiagramme und Phasen des Al-Mg-Zn Systems 16 3 Experimentelle Methoden und Theoretische Berechnungen 24 3.1 Ausgangsstoffe 24 3.2 Präparation der Proben 24 3.2.1 Schmelzspinnen 25 3.2.2 Schmelzzentrifugation 26 3.2.3 Abkühlvarianten 26 3.3 Charakterisierung der Legierungen 27 3.3.1 Chemische Analysen 27 3.3.2 Metallografie, Röntgenspektroskopie, Elektronenbeugung 28 3.3.3 DSC- und Massendichtemessungen, Messungen des elektrischen Widerstands 29 3.3.4 Pulver-Röntgendiffraktion und Pulver-Neutronendiffraktion 29 3.3.5 Einkristall-Röntgendiffraktion 30 3.4 Theoretische Berechnungen 31 3.4.1 Berechnungen der elektronischen Struktur 31 3.4.2 Gesamtenergieberechnungen 31 3.4.3 Calphad-Berechnungen und DTA-Simulation 32 4 Ergebnisse 34 4.1 Die Phi-Phase 34 4.1.1 Phasenanalyse 35 4.1.2 Physikalische Eigenschaften 44 4.1.3 Kristallchemie 45 4.1.4 Ergebnisse der Gesamtenergieberechnungen, DOS 57 4.2 Die tau-2-Phase 59 4.2.1 Phasenanalyse 60 4.2.2 Strukturmodellierung mit kanonischen Zell-Parkettierungen 73 4.2.3 Strukturverfeinerung 77 4.2.4 Kristallchemie 83 4.2.5 Ergebnisse der Gesamtenergieberechnungen 88 4.3 Primäre Phasenfelder der Mg-reichen Seite des Al-Mg-Zn Systems und die q-Phase 93 4.3.1 Die quasikristalline Phase q und ihr komplex-reguläres Eutektikum 98 4.4 Neue komplexe intermetallische Verbindungen im Al-Mg-Zn System 106 4.4.1 Phasenanalytische Untersuchungen in der Nähe des binären Teilsystems Mg-Zn 106 4.4.2 Physikalische Eigenschaften 113 4.4.3 Kristallchemie 114 4.4.3.1 Die beta-Zn-Phase 114 4.4.3.2 Die tau-d-Phase, ein dekagonaler Approximant 125 4.4.3.3 Die lambda-Phase 134 5 Zusammenfassung 141 6 Literatur 149 A Anhang 159 A.1 Verfeinerung der Einkristall-Röntgenbeugungsdaten 159 A.2 Grundlagen der DTA-Simulation 160 A.2.1 DTA-Simulation in VBA für den Excel-Export von Pandat2012 161 A.3 Zusätzliche Information über die Phi-Phase des Al-Mg-Zn Systems 168 A.3.1 Informationen zu den effektiven Paarpotentialen für das ternäre Al-Mg-Zn System 172 A.4 Zusätzliche Informationen über die tau-2-Phase im Al-Mg-Zn System 175 A.5 Zusätzliche Informationen über die Abtastung der primären Phasenfelder 180 A.6 Zusätzliche Informationen über die beta-Zn-Phase im System Al-Mg-Zn 185 A.7 Zusätzliche Informationen über die tau-d-Phase im System Al-Mg-Zn 191 A.8 Zusätzliche Informationen über die lambda-Phase im System Al-Mg-Zn 195 / The elements Al, Mg and Zn are major components for a large number of light and high strength alloys, such as the Al-based alloys of the 7xxx series. In addition, the Al-Mg-Zn system has attracted much interest because four complex metallic alloy phases, called τ1, τ2, Φ and q are formed as ternary intermetallic compounds. The current experimental phase diagrams of the Al-Mg-Zn system contain only provisional or no homogeneity ranges of the Φ phase, τ2 phase and the q phase due to insufficient experimental data. The aim of the work was to redetermine the homogeneity ranges of the q, τ2 and the Φ phases and to determine the crystal structure of the Φ phase for a reliable data set. Samples were prepared by furnace-controlled melting and annealing in Ta ampoules or by centrifugation from the self-flux and characterized by XRD, SEM, EDXS, WDXS and DSC. While reinvestigating the Al-Mg-Zn phase equilibria in the vicinity of the subsystem Mg-Zn close to τ1, a number of new ternary phases were discovered. Single phase material could be obtained for the known Φ and τ2 phases and for four new intermetallic compounds. The crystal structures for the Φ phase and two of the new intermetallic compounds were solved and the crystal structure of the τ2 phase was reinvestigated. While τ2 (Pa-3, a = 23.034(3) Å) is an approximant of the icosahedral quasicrystalline phase q, the Φ phase (Pbcm, a = 8.9374(2) Å, b = 16.812(3) Å, c = 19.586(4) Å) and one of the new phases (Imm2, a = 5.2546(2), b = 40.240(2), c = 25.669(1) Å) turned out to be decagonal approximants. Surprisingly, we have found one phase (Fd-3m, a = 27.5937 (9) Å) isotypic to the Samson’s phase β-Al3Mg2 at Zn rich composition.:1 Einleitung 1 2 Grundlagen 5 2.1 Frank-Kasper-Phasen und tetraedrisch dicht gepackte Strukturen 5 2.2 Parkettierungen, Quasikristalle and Approximanten 11 2.3 Phasendiagramme und Phasen des Al-Mg-Zn Systems 16 3 Experimentelle Methoden und Theoretische Berechnungen 24 3.1 Ausgangsstoffe 24 3.2 Präparation der Proben 24 3.2.1 Schmelzspinnen 25 3.2.2 Schmelzzentrifugation 26 3.2.3 Abkühlvarianten 26 3.3 Charakterisierung der Legierungen 27 3.3.1 Chemische Analysen 27 3.3.2 Metallografie, Röntgenspektroskopie, Elektronenbeugung 28 3.3.3 DSC- und Massendichtemessungen, Messungen des elektrischen Widerstands 29 3.3.4 Pulver-Röntgendiffraktion und Pulver-Neutronendiffraktion 29 3.3.5 Einkristall-Röntgendiffraktion 30 3.4 Theoretische Berechnungen 31 3.4.1 Berechnungen der elektronischen Struktur 31 3.4.2 Gesamtenergieberechnungen 31 3.4.3 Calphad-Berechnungen und DTA-Simulation 32 4 Ergebnisse 34 4.1 Die Phi-Phase 34 4.1.1 Phasenanalyse 35 4.1.2 Physikalische Eigenschaften 44 4.1.3 Kristallchemie 45 4.1.4 Ergebnisse der Gesamtenergieberechnungen, DOS 57 4.2 Die tau-2-Phase 59 4.2.1 Phasenanalyse 60 4.2.2 Strukturmodellierung mit kanonischen Zell-Parkettierungen 73 4.2.3 Strukturverfeinerung 77 4.2.4 Kristallchemie 83 4.2.5 Ergebnisse der Gesamtenergieberechnungen 88 4.3 Primäre Phasenfelder der Mg-reichen Seite des Al-Mg-Zn Systems und die q-Phase 93 4.3.1 Die quasikristalline Phase q und ihr komplex-reguläres Eutektikum 98 4.4 Neue komplexe intermetallische Verbindungen im Al-Mg-Zn System 106 4.4.1 Phasenanalytische Untersuchungen in der Nähe des binären Teilsystems Mg-Zn 106 4.4.2 Physikalische Eigenschaften 113 4.4.3 Kristallchemie 114 4.4.3.1 Die beta-Zn-Phase 114 4.4.3.2 Die tau-d-Phase, ein dekagonaler Approximant 125 4.4.3.3 Die lambda-Phase 134 5 Zusammenfassung 141 6 Literatur 149 A Anhang 159 A.1 Verfeinerung der Einkristall-Röntgenbeugungsdaten 159 A.2 Grundlagen der DTA-Simulation 160 A.2.1 DTA-Simulation in VBA für den Excel-Export von Pandat2012 161 A.3 Zusätzliche Information über die Phi-Phase des Al-Mg-Zn Systems 168 A.3.1 Informationen zu den effektiven Paarpotentialen für das ternäre Al-Mg-Zn System 172 A.4 Zusätzliche Informationen über die tau-2-Phase im Al-Mg-Zn System 175 A.5 Zusätzliche Informationen über die Abtastung der primären Phasenfelder 180 A.6 Zusätzliche Informationen über die beta-Zn-Phase im System Al-Mg-Zn 185 A.7 Zusätzliche Informationen über die tau-d-Phase im System Al-Mg-Zn 191 A.8 Zusätzliche Informationen über die lambda-Phase im System Al-Mg-Zn 195

Introduction : L’utilisation des méthodes anatomiques classiques rend difficile la localisationprécise des micro-fibres nerveuses et ne permet pas de déterminer leur nature ni leur fonction.La chirurgie pelvienne est associée à des séquelles urinaires et sexuelles fréquentes causéespar lésion iatrogène des nerfs pelviens. La connaissance de l’anatomie et de la physiologie del’innervation intra-pelvienne est fondamentale pour tenter de réduire le taux de troublesfonctionnels postopératoires.Objectifs : i) étudier l’anatomie topographique et la nature de fibres nerveuses intrapelvienneen utilisant la reconstruction tridimensionnelle des coupes histologiques immunomarquéesii) standardiser la technique de Dissection Anatomique Assistée par Ordinateur(DAAO) et vérifier sa faisabilité sur des sujets adultes et iii) établir grâce à cette technique deDAAO des modèles pédagogiques tridimensionnels afin d’améliorer la compréhension desdysfonctions sphinctériennes et sexuelles survenant après la chirurgie (rectale et prostatique)et d’adapter éventuellement la technique opératoire.Matériel et méthodes : Des coupes histologiques sériées de pelvis ont été réalisées chez septfoetus masculins, sept foetus féminins et six cadavres adultes masculins. Les coupes ont ététraitées par des méthodes histologiques (Hématoxyline-Eosine et trichrome de Masson) etimmuno-histochimiques pour détecter les fibres nerveuses (anti-S100), les fibres somatiques(anti-PMP22), les fibres adrénergiques (anti-TH), cholinergiques (anti-VAChT), sensitives(anti-SP/CGRP) et nitrergiques (anti-nNOS) ainsi que l’actine lisse des sphincters. Les lamesont ensuite été numérisées par un scanner de haute résolution optique et les imagesbidimensionnelles ont été reconstruites en trois dimensions grâce au logiciel WinSurf.Résultats: La reconstruction tri-dimensionnelle des coupes histologiques immuno-marquéesa permis d'identifier l’anatomie topographique et structurelle de l’innervation intra-pelvienne.Les structures nerveuses afférentes du plexus hypogastrique inférieur (PHI) : nerfssplanchniques pelviens (NSP) et nerfs hypogastriques (NH) véhiculent de façon mixte l’influxsympathique et parasympathique pelvien.Les fibres nerveuses issues de la partie distale du PHI sont responsables de la continenceurinaire et de la fonction sexuelle. Elles sont regroupées et associées au pédicule vasculairepour former la bandelette neuro-vasculaire (BNV). Trois efférences principales sont issues decette BNV : i) des fibres antérieures destinées au sphincter urétral, ii) des fibres antérolatérales,par rapport à la prostate et au vagin, constituant le nerf caverneux destiné aux corpscaverneux du pénis/clitoris et iii) des fibres nerveuses postéro-latérales, par rapport à laprostate et au vagin, formant le « nerf spongieux » destiné aux corps spongieux/bulbesvestibulaires.Les communications autonomiques-somatiques entre le PHI supra-lévatorien et le nerfpudendal infra-lévatorien existent à trois niveaux ; proximal, intermédiaire et distal. Lacommunication distale caverno-pudendale est responsable de l’activité érectile segmentaireobservée au sein du nerf dorsal du pénis/clitoris.Conclusion: La DAAO est une méthode originale de recherche anatomique qui a étéprogressivement améliorée au sein de notre unité de recherche. Cette évolution illustre le faitque l'anatomie descriptive est encore une science dynamique. Notre étude a permis dedévelopper des modèles anatomo-physiologiques d’innervation pelvienne contribuant àaméliorer du point de vue morphologique, chirurgical et pédagogique la compréhension derégions anatomiques complexes comme le petit bassin. / Introduction: Classic anatomical methods have limitations in micro determination of nervefibre location. Furthermore, the precise detection of the nerve fibres nature is not possible bymeans of dissection. Pelvic surgery is associated with urinary and sexual consequence causedby iatrogenic damage of the pelvic nerves. Anatomic and physiologic knowledge of the intrapelvicinnervation is essential to reduce the rate of postoperative functional complication.Objectives: i) to study the topographic anatomy and the nature of intra-pelvic nerve fibersusing three-dimensional reconstruction of histological immuno-labeled sections ii)standardize the technique of Computer-Assisted Anatomic Dissection (CAAD) and check itsfeasibility on adult subjects iii) reconstructe three dimensional teaching models to improveunderstanding of urinary and sexual dysfunction occurring after surgery (of rectal and ofprostate) to ameliorate the operative technique.Materials and methods: serial histological sections of pelvic portion were performed inseven male foetuses, seven female foetuses and six adult male cadavers. The sections weretraited by histological methods (Hematoxylin-Eosin and Masson's trichrome) and immunohistochemicalmarker of the nerve fibers (anti-S100), the somatic fibers (anti-PMP22), theadrenergic (anti-TH), cholinergic (anti-VAChT), sensory (anti-SP/CGRP) and nitrergic (antinNOS)fibers and the actin smooth muscles. The slides were then digitized by a scanner ofhigh optical resolution and two-dimensional images were reconstructed in three dimensionsusing WinSurf software.Results: The three dimensional reconstruction of histological immuno-labelled sectionsidentified structural and topographic anatomy of intra-pelvic innervation. The afferencenerves of the inferior hypogastric plexus (IHP): pelvic splanchnic nerves (PSN) andhypogastric nerves (HN) contain both sympathetic and parasympathetic fibers.The nerve fibers from the distal part of the IHP is responsible for urinary continence andsexual function. They are grouped and associated with the vascular pedicle to form theneurovascular bundles (NVB). Efferences of this NVB are distributed in three maindirections: i) anterior fibers the urethral sphincter, ii) anterolateral fibers, compared withprostate / vagina, which constitute the cavernous nerve for the corpora cavernosa of the penis/ clitoris and iii) " spongious nerve”, which is the continuity of posterior-lateral nerve fibers,compared with prostate / vagina, for the corpus spongiosum / vestibular bulbs.Autonomic-somatic communications between supra-lavator IHP and infra-levator pudendalnerve are present at three levels; proximal, intermediate and distal communications. Cavernopudendaldistal communication provides segmental erectile activity of the dorsal nerve of thepenis / clitoris.Conclusion: The CAAD is an original method in anatomical research which has beenprogressively improved. This illustrates the fact that descriptive anatomy is still a dynamicscience. Our study has developed anatomico-physiological models of intra-pelvic innervationcontributing to a better understanding of complex anatomical

An understanding of compartment fire behaviour is important for fire protection engineers. For design purposes, whether to use a prescriptive code or performance based design, life safety and property protection issues are required to be assessed. The use of design fires in computer modelling is the general method to determine fire safety. However these computer models are generally limited to the input of one design fire, with consideration of the complex interaction between fuel packages and the compartment environment being simplified. Of particular interest is the Heat Release Rate, HRR, as this is the commonly prescribed design parameter for fire modelling. If the HRR is not accurate then it can be subsequently argued that the design scenario may be flawed. Therefore the selection of the most appropriate fire design scenario is critical, and an increased level of understanding of compartment behaviour is an invaluable aid to fire engineering assumptions. This thesis details an experimental study to enhance the understanding of the impact and interaction that the size and location of pool fires within an enclosure have upon the compartment fire behaviour. Thirty four experiments were conducted in a reduced scale compartment (½ height) with dimensions of 3.6m long by 2.4m wide by 1.2m high using five typical ventilation geometries (fully open, soffit, door, window and small window). Heptane pool fires were used, located in permutations of three evenly distributed locations within the compartment (rear, centre and front) as well as larger equivalent area pans located only in the centre. This thesis describes the experimental development, setup and results of the experimental study. To assist in the classification of compartment fire behaviour during the experiments, a ‘phi’ meter was developed to measure the time dependent equivalence ratio. The phi meter was developed and configured to measure O₂, CO₂ and CO. The background development, calibration, and experimental results are reported. A review of compartment fire modelling using Fire Dynamics Simulator, has also been completed and the results discussed. The results of this experimental study were found to have significant implications for Fire Safety Engineering in that the size of the fire is not as significant as the location of the fire. The effect of a fire near the vent opening was found to have a significant impact on compartment fire behaviour with the vent located fuel source increasing the total compartment heat release rate by a factor of 1.7 to that of a centrally placed pool fire of the same total fuel area. The assumption that a fire located in the centre of the room provides for the highest heat release rate is not valid for post-flashover compartment fires. The phi meter was found to provide good agreement with the equivalence ratio calculated from total compartment mass loss rates, and the results of FDS modelling indicate that the use of the model in its current form can not be applied to complex pool fire geometries.

Abstact: The overall objective of this thesis is to draw attention to discussion as a teaching technique. Discussion can be used to develop pupils' abilities, which are necessary for social life. The question: "How do teachers understand this technique and then apply it?", is closely linked to this problem. It is worth mentioning that discussion has very bad connotations in the Czech society. It is mainly due to its representation in media, where discussion is usually shown as a fight of arguments with an arrogant attitude, unethical and self-centred word-tiffs. The only goal is to state one's case very fast and to silence the rival. Where else can a different concept of discussion be seen? Where can we encounter discussion that resembles a dialogue? In my oppinion it is at school. I believe that if discussion is used in the right way at school it can help the society. I consider this as a very current issue and its solution very useful. This thesis is based on an assumption that teachers work with this educational technique in an intuitive way and they do not often take advantage of possibilities offered by the discussion that could develop pupils' personal abilities. The main objective of this thesis is to offer a more extensive theoretical background. It means to define the concept of a discussion with...

We consider the distribution of the zero and typical cells of a (homogeneous) Poisson hyperplane tessellation. We give a direct proof adapted to our setting of the well known Complementary Theorem. We provide sharp bounds for the tail distribution of the number of facets. We also improve existing bounds for the tail distribution of size measurements of the cells, such as the volume or the mean width. We improve known results about the generalised D.G. Kendall's problem, which asks about the shape of large cells. We also show that cells with many facets cannot be close to a lower dimensional convex body. We tacle the much less study problem of the number of facets and the shape of small cells. In order to obtain the results above we also develop some purely geometric tools, in particular we give new results concerning the polytopal approximation of an elongated convex body.

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