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21	Characterization Of Electrolyte And Pyrotechnic Powders And Pellets Kalender, Volkan 01 February 2011 (has links) (PDF) Electrolyte and pyrotechnic pellets are two important components of thermal batteries. Both electrolyte and pyrotechnic pellets are produced by cold compaction of constituent powders. These compacts are integrated in the battery as pellets with sufficient green density, green strength, calorific energy and burning rate (for pyrotechnic only) to provide high performance batteries. In this study, effects of physical properties of the used powders such as particle size distribution, average particle size, particle shape and composition of components and applied compression pressure and their interactions on green density and green strength of electrolyte pellets and in addition, calorific energy and burning rate of pyrotechnic pellets were examined. Statistical experimental designs were constructed to investigate the main and interaction effects of studied variables. 24 two factorial statistically designed experiments&rsquo / results for pyrotechnic pellets exhibited that the compression pressure and iron powder morphology were the most significant factors improving green density and break strength of pyrotechnic pellets. It was shown that the compression pressure had a negative effect on burning rate. Both calorific output and burning rate were increased significantly by increasing KClO4 fraction. In addition, decreasing particle size of KClO4 had also a positive effect on burning rate. The maximum calorific output was obtained at maximum KClO4 fraction. 23 two factorial statistically designed green strength and green density experiments&rsquo / results of electrolyte pellets revealed that, compression pressure was again the dominating factor. Moreover, there was a tendency for higher green density with lower MgO fraction and electrolyte powder average particle size. Besides, the positive effect of decreasing average particle size on green strength was investigated distinctly at low green density values. From the thermal battery perspective, main and interaction effects of variables on the characteristics of electrolyte and pyrotechnic pellets were successfully examined. QD Chemistry 1-999
22	Combustion confinée d'explosif condensé pour l'accélaration de projectile. Application en pyrotechnie spatiale / Confined combustion of high explosives for projectile acceleration. Applications in the field of space pyrotechnics Nicoloso, Julien 18 June 2014 (has links) L’opto-pyrotechnie (amorçage de la détonation par système optique) est l’une des innovations les plus prometteuses en termes de fiabilité, de sécurité et de performances pour les futurs lanceurs spatiaux. Le but de la thèse est d’étudier et de modéliser le premier des deux étages d’un Détonateur Opto-Pyrotechnique, constitué d’un explosif confiné dans une chambre de combustion fermée où se déroulent les premières phases d’une Transition Déflagration-Détonation. L’amorçage par laser de l’explosif puis la combustion en chambre isochore sont traités par le code EFAE, lequel est couplé au logiciel LS-DYNA qui simule la déformation et la rupture du disque de fermeture de la chambre, puis la propulsion du projectile résultant vers le second étage. En parallèle, diverses techniques expérimentales (adsorption de gaz, vélocimétrie hétérodyne, microscopie) ont mis en valeur plusieurs procédés physiques, ce qui a permis de tester le couplage entre EFAE et LS-DYNA, puis de déterminer et de hiérarchiser les paramètres affectant les critères industriels. / Opto-pyrotechnics (ignition of detonation by optical systems) is one of the most promising innovations to improve reliability, safety and performances on future space launchers. This thesis aims at studying and modeling the first stage from a two-stage opto-pyrotechnic detonator that consists of a condensed explosive confined in a closed combustion chamber, in which the beginning of a Deflagration-to-Detonation Transition occurs. The laser ignition of the explosive and its isochoric combustion are modeled by the EFAE code. This code is coupled with LS-DYNA software to deal with the deformation and the rupture of the metallic disk that closes the combustion chamber, and then with the subsequent propulsion of the projectile to the second stage. In parallel, various experimental technics (gas adsorption, photonic Doppler velocimetry, microscopy) have underlined several physical processes that allow first to test the coupling between EFAE and LS-DYNA, then to determine and classify influent parameters that affect the industrial specifications. Opto-pyrotechnie Transition déflagration-détonation Modèle bi-phasique Opto-pyrotechnics Deflagration-to-detonation transition Two-phase model 620
23	Trygg på fotboll : - Supportrars upplevda trygghet på Eleda Stadion / Secure at Football : - Supporters' Sense of Security at Eleda Stadion Persson, Viktor, Sernbo, Philip January 2022 (has links) Denna studie behandlar supportrars upplevda trygghet på Eleda Stadion i Malmö under fotbollsmatcher. Kunskapen om supportrars trygghet på allsvenska arenor är begränsad, men samtidigt så har ämnet fått ett stort utrymme i media de senaste åren. Syftet med den här studien är därmed att undersöka trygghetsupplevelsen vid fotbollsmatcher på Eleda Stadion, vad som påverkar den och hur den skiljer sig mellan olika grupper. Frågeställningarna som studien ämnar besvara är följande: “Hur upplever supportrar tryggheten vid fotbollsmatch på Eleda Stadion?”, “Hur påverkar bakgrundsfaktorer, ordningsstörningar, aktörer, förtroende samt tidsliga faktorer trygghetsupplevelsen på Eleda Stadion?” och “Hur varierar trygghetsupplevelsen mellan sittplats och ståplats, samt mellan män och kvinnor?”. Studien har använt sig av både en kvantitativ respektive kvalitativ metod för att besvara frågeställningarna i form av en enkätundersökning samt intervjuer. Urvalet bestod av personer över 15 år gamla som varit på en Malmö FF-match på Eleda Stadion de senaste 12 månaderna. Datainsamlingen skedde genom att dela ut enkäter i samband med matcher samt digitalt på Facebook och forumet Svenska Fans. Personer som intervjuades hade själva önskat om att få delta via enkäten. Datamaterialet analyserades utifrån flera metoder i form av bivariat-, univariat-, och regressionsanalys för enkäten samt tematisk analys för intervjumaterialet. I resultatet framkom det att den upplevda tryggheten var stor samtidigt som den påverkades av ett antal faktorer och skilde sig mellan olika grupper. Pyroteknik var den faktorn som påverkade tryggheten mest samtidigt som flera ansåg det som stämningshöjande. Motståndarsupportrar var även det en faktor som påverkade tryggheten negativt. Den aktuella studien ämnar bidra till en aktuell bild och förbättrad kunskap om den upplevda tryggheten i samband med fotbollsmatcher i framför allt Malmö, men kan även ge en bild för tryggheten på övriga allsvenska arenor runt om i Sverige. / This study deals with the subject of supporters’ sense of security at Eleda Stadion in Malmö during football matches. The knowledge of supporters’ sense of security is limited, but at the same time the subject has been given a lot of room in media the last years. The aim of this study is thus to examine the sense of security during football matches at Eleda Stadion, what affects it and how it differs between groups. The study intends to answer the following questions: “What is supporters’ sense of security during football matches at Eleda Stadion?”, “How do the background factors, disturbances, actors, trust and temporal factors affect the sense of security at Eleda Stadion?” and “How does the sense of security vary between the sitting and standing crowd as well as between men and women?”. Both a quantitative and qualitative method has been used to answers the questions in form of a questionnaire survey as well as interviews. The selection consisted of people over the age of 15 who have been to a Malmö FF match in the last 12 months. The collection of data was acquired by handing out the survey in conjunction with the matches as well as digital on Facebook and the forum Svenska Fans. Individuals who were interviewed had themselves wished to participate via the survey. The data was analysed using different methods in form of bivariate-, univariate-, and regression analysis for the survey and thematic analysis for the interviews. The result showed that the perceived sense of security was high while being affected by several factors and differed between groups. Pyrotechnics was the factor that affected the sense of security the most, while many still considered it to contribute to the atmosphere. The opposing supporters was also a factor that impacted the sense of security negatively. This study intends to contribute to a current depiction and improved knowledge of the sense of security in conjunction football matches, especially in Malmö, but can also provide a picture of the sense of security in other arenas in Allsvenskan around Sweden. football pyrotechnics secure supporters trust fotboll förtroende pyroteknik supportrar trygghet Social Sciences Interdisciplinary
24	Caractérisation et modélisation du comportement lors de l'allumage de poudres propulsives à vulnérabilité réduite en balistique intérieure / Experimental characterization and numerical modeling of the ignition of low vulnerability gun propellants in interior ballistics Boulnois, Christophe 30 May 2012 (has links) Les poudres propulsives pour armes sont des matériaux énergétiques dont la combustion permet l’accélération de projectiles jusqu’à des vitesses importantes. Ces matériaux énergétiques sensibles peuvent être soumis à de fortes contraintes (chocs, impacts et incendies) lors de leur utilisation. Le remplacement de certaines substances entrant dans leur formulation permet de diminuer leur vulnérabilité. En conséquence, ces poudres propulsives présentent une dynamique d’allumage différente. Ce travail de recherches est consacré à l’allumage des poudres propulsives pour armes et se présente en quatre chapitres. Un état de l’art sur le sujet est réalisé. Il porte en particulier sur la phénoménologie de l’allumage, la caractérisation de poudres propulsives, et la modélisation de l’allumage. Deux poudres propulsives sont expérimentalement analysées par thermogravimétrie, calorimétrie et spectrométrie de masse. Cette analyse permet de caractériser les différentes étapes cinétiques de la dégradation thermique de ces poudres propulsives. Un code de modélisation biphasique 2D est développé pour servir de support à la comparaison de modèles d’allumage. Le modèle implémenté décrit la chambre de combustion du canon dans les premières phases du coup de canon, lorsque le lit de poudre propulsive est compacté et que les gaz issus du dispositif pyrotechnique d’allumage le parcourent. Un modèle d’allumage est développé à partir des résultats expérimentaux obtenus au deuxième chapitre. Le code de calcul précédemment évoqué permet de comparer l’influence de différents modèles sur la propagation de l’allumage. / Gun Propellants are energetic materials whose combustion can accelerate projectiles to high speeds. These sensitive energetic materials can be subjected to high stresses (shocks, impacts and fires), potentially able to ignite them. The modification of their chemical formulation reduces such vulnerability. Consequently, these propellants have different ignition dynamics. This work focuses on the ignition of gun propellants and comes in four chapters. A state of the art on the subject is firstly made. It focuses on the phenomenology of the ignition and on energetic materials experimental characterization, and modeling of their ignition. Two gun propellants are experimentally analyzed by thermogravimetry, calorimetry and mass spectrometry. This analysis allows characterizing the various stages of the degradation kinetics of these propellants. A 2D biphasic modeling code was developed to provide support for the comparison of ignition models. It describes the combustion chamber in the early stages of the gun firing, when the propellant bed is compacted and the gases from the pyrotechnic igniter are flowing through it. An ignition model is developed from the experimental data obtained in the second chapter. The previously mentioned modeling code allows comparing the influence of different ignition models on the spreading speed of the ignition signal through the packed bed of propellant. Matériaux énergétiques Poudres propulsives Balistique intérieure Allumage Analyse thermique Thermogravimétrie Calorimétrie Spectrométrie Analyse cinétique Ecoulement réactif Pyrotechnie Vulnérabilité réduite Modélisation biphasique Energetic materials Propellants Interior ballistics Firing Thermal analysis Thermogravimetry Calorimetry Spectrometry Kinetic analysis Reactive flow Pyrotechnics Low vulnerability Biphasic modeling
25	Johann Friedrich von Uffenbach. Sammler – Stifter – Wissenschaftler / Johann Friedrich von Uffenbach. Collector - Donor - Scientist Meyerhöfer, Dietrich 28 January 2020 (has links) No description available. 700 Sammeln Uffenbach Frankfurt am Main Wissenschaftliche Gesellschaft Zeichnung Optische Geräte Instrumente zur Gnomonik Astronomische Instrumente 18. Jahrhundert Druckgraphik Sammlungsgeschichte Privatgelehrter Kavaliersreise Bildungsreise Tagebücher Reisetagebücher Auktionswesen Auktionen Auktion Florsheim Geschichte des Sammelns Inventare von Druckgraphik Auktionskatalog Auktionskataloge Gegenschreiberbuch Monogrammistenlexikon Künstlermonogramme Stiftung Göttingen Georg-August-Universität Göttingen Kupferstich Holzschnitt Radierung Sammler Kunstmarkt im 18. Jahrhundert Grand Tour Frankfurter Patrizier Malerakademie Akademie der Wissenschaften Alte Mainbrücke Architekt Architektur Astronomie Bibliothek Bibliotheken Bibliothekswesen Buchhandel Buchhändler Diarien Diarium Direktdruck Drechseln Drechsler Drehbank Druckzustand Enkaustik Fehldruck Fernrohr Fernrohre Festungsbau Feuerwerk Feuerwerkerei Findbuch Findbücher Firnis Firniß Fontäne Fortifikation Geografie Geographie Geometrie Goethehaus Hobelbank Kartographie Klebeband Korrespondenz Kunsthandel Kunsthändler Kunstsammlung Landkarte Landkarten Ludwig XIV. Materialist Mikroskop Mikroskope Mineralienkabinett Naturdruck Oper Optik Prinzmetall Protokoll Pumpenanlage Reisebericht Sammelmappe Schildpatt Sonnenuhr Sonnenuhren Teleskop Teleskope Topographie Vakuumpumpe Vergantung Wassermaschine Wasserspiele Repertorium Protokollband Protokollbände Protokolle Georgia-Augusta Atzenheim Friedrich Philipp von Behaghel Philipp Jacob Benson William Bérain Jean Bernstorff Johann Hartwig Ernst Graf von Bignon Jean–Paul Böhm Johann Christian Breitkopf Bernhard Christoph Buttieri Carlo Antonio Campani Giuseppe Chiarelli Antonio Christ Johann Friedrich Heumann Christoph August Culpeper Edward d’Osangis Jean Pigeon Daimant Le Maire Pierre Dathan Johann Georg Dietzsch Johann Israel Diesterweg Albert Adolf Eberhard Conrad Hieronymus, gen. Schwind Egell Paul Ettling Johann Friedrich Fasch Johann Friedrich Fer Nicolas de Geysel Johann Daniel Goethe Johann Caspar Gottsched Johann Christoph Graupner Christoph Grünewald Gottfried Häckel Heinrich Jakob von Leth Hendrick de Heß Peter Heyne Christian Gottlob Hotteterre Jacques-Martin Hugo Friedrich Ludolph von Marshall John Kaller Johann Christian Kinet Johann Melchior Kniphof Johann Hieronymus Kißner Johann Georg Largillière Nicolas Leth Andries de Mariette Pierre Jean Marolles Michel de Mascow Gottfried Metz Conrad Michu Benoit Moritz Johann Friedrich Münchhausen Gerlach Adolf von Muth Heinrich Ludwig Musschenbroeck Pieter van Pütter Johann Stephan Richter Georg Gottlob Rigaud Hyacinthe Schelhorn Johann Georg Schürmann Georg Caspar Schütz d.Ä. Christian Georg Scotin Gerard Senckenberg Heinrich Christian von Stanislaus I. Leszynski Telemann Georg Philipp Ucheln Heinrich von Uffenbach Johann Friedrich von Uffenbach Wilhelm von Uffenbach Zacharias Conrad von Visscher Nicolaes Wagner Joseph Wolf Johann Christoph Zeller Franz Frauenstein Patriziergesellschaft Collecting Uffenbach Frankfurt am Main Scientific society Drawing optical devices gnomonic instruments Astronomical instruments 18. century Prints history of collection private scholar grand tour diary travel diaries Auctioning Auctions auction Florsheim History of collecting Print graphic inventories Auction catalog Auction catalogs Counter-writing book Monogrammist encyclopedia Artist monograms donation Goettingen Georg-August-University of Goettingen engraving woodcut etching collector Art market in the 18th century Frankfurt patrician Academy of painters Academy of Science Old Main Bridge architect architecture astronomy Library Libraries Librarianship Book trade Bookseller Diaries Diarium Direct printing Turning Turner Lathe Print condition Encaustic Misprint Telescope Telescopes Fortress construction Fireworks pyrotechnics repertory repertories varnish fountain fortification geography geometry Goethe House carpenter’s bench cartography Correspondence Art trade Art dealer Art collection map maps Louis XIV microscope microscopes Mineral cabinet Natural print Opera Optics minutes Pump system Account of a journey file Tortoiseshell sundial sundials topography Vacuum pump waterworks Atzenheim Friedrich Philipp von Behaghel Philipp Jacob Benson William Bérain Jean Bernstorff Johann Hartwig Ernst Graf von Bignon Jean–Paul Böhm Johann Christian Breitkopf Bernhard Christoph Buttieri Carlo Antonio Campani Giuseppe Chiarelli Antonio Christ Johann Friedrich Heumann Christoph August Culpeper Edward d’Osangis Jean Pigeon Daimant Le Maire Pierre Dathan Johann Georg Diesterweg Albert Adolf Dietzsch Johann Israel Eberhard Conrad Hieronymus, gen. Schwind Egell Paul Ettling Johann Friedrich Fasch Johann Friedrich Fer Nicolas de Geysel Johann Daniel Goethe Johann Caspar Gottsched Johann Christoph Graupner Christoph Grünewald Gottfried Häckel Heinrich Jakob von Leth Hendrick de Heß Peter Heyne Christian Gottlob Hotteterre Jacques-Martin Hugo Friedrich Ludolph von Marshall John Kaller Johann Christian Kinet Johann Melchior Kißner Johann Georg Kniphof Johann Hieronymus Largillière Nicolas Leth Andries de Mariette Pierre Jean Marolles Michel de Mascow Gottfried Metz Conrad Michu Benoit Moritz Johann Friedrich Münchhausen Gerlach Adolf von Muth Heinrich Ludwig Musschenbroeck Pieter van Pütter Johann Stephan Richter Georg Gottlob Rigaud Hyacinthe Schelhorn Johann Georg Schürmann Georg Caspar Schütz d.Ä. Christian Georg Scotin Gerard Senckenberg Heinrich Christian von Stanislaus I. Leszynski Telemann Georg Philipp Ucheln Heinrich von Uffenbach Johann Friedrich von Uffenbach Wilhelm von Uffenbach Zacharias Conrad von Visscher Nicolaes Wagner Joseph Wolf Johann Christoph Zeller Franz Georgia-Augusta Frauenstein Kunst (PPN613163508)

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