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<b>Closed Vessel Burning Rate Measurements of Composite Propellants Using Microwave Interferometry</b>Shane A Oatman (18396357) 17 April 2024 (has links)
<p dir="ltr">Burning rate as a function of pressure is one of the primary evaluation metrics of solid propellants. Most solid propellant burning rate measurements are made at a nearly constant pressure using a variety of measurement approaches. This type of burning rate data is highly discretized and requires many tests to accurately determine the burning rate response to pressure. It would be moreefficient to measure burning rate dynamically as pressures are varied. Techniques used to make transient burning rate measurements are reviewed briefly and initial results using a microwave interferometry (MI) technique are presented. The MI method used in tandem with a closed bomb enables nearly continuous measurement of burning rates for self-pressurizing burns, capturing burning rate data over a wide range of pressures. This approach is especially useful for characterization of propellants with complex burning behaviors (e.g., slope breaks or mesa burning). The burning rates of three research propellants were characterized over a pressure range of 0.101-24.14 MPa (14-3500 psi). One research propellant exhibited a slope break at a pressure of 6.63 MPa (960 psi). Using MI in a closed pressure vessel, 14 propellant strand burns resulted in a nearly continuous burning rate curve over a pressure range of 0.41-24.13MPa (60-3500psi) that reasonably matched conventional burning rate measurements. The development of this technique provides an opportunity to quickly characterize the burning rate curve of solid propellants with greater fidelity and efficiency than traditional quasi-static pressure testing techniques.</p>
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The Weekend of Dermot & Grace: Dlouhá modernistická báseň Eugena R. Watterse / The Weekend of Dermot & Grace: Eugene R. Watters' Long Modernist PoemSvětlík, Martin January 2016 (has links)
The oeuvre of the Irish poet, novelist, playwright and essayist Eugene Rutherford Watters (later publishing under the name Eoghan Ó Tuairisc), who wrote both in English and Irish, has been mostly neglected by literary criticism. This thesis focuses on Watters' ambitious long modernist poem The Week-End of Dermot and Grace (1964), which has so far received only perfunctory critical treatment. Formally, The Week-End shows clear affinities with the works of high modernism (especially with the poetry of T.S. Eliot), especially in terms of poly- and multivocal qualities of Watters' overtly allusive language and the liberal employment of wide-ranging intertextual references. On the thematic level, the poem centres around Watters' preoccupation with the dropping of the first atomic bomb on Hiroshima on 6th August 1945 by the American forces, a momentous event that impelled the poet to questions about faith, civilisation, technology, and collective guilt in the context of the Irish neutral stance during the Second World War. Reflections on Hiroshima also led him to contemplate the role of the poet and poetry in the modern "atomic age". Given the aforementioned qualities of the work, the method chosen for the analysis consists of a close reading of the poem in the light of the historical, literary, and...
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里山からキツネが消えた日 : 豊田市小手沢町の地蔵堂から見つかったキツネの遺骸Ikeda, Akiko, Minami, Masayo, Nakamura, Toshio, Suzuki, Kazuhiro, 池田, 晃子, 南, 雅代, 中村, 俊夫, 鈴木, 和博 03 1900 (has links)
第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告
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Assessing internal contamination after a radiological dispersion device event using a 2x2-inch sodium-iodide detectorDewji, Shaheen Azim 08 April 2009 (has links)
The detonation of a radiological dispersion device (RDD) may result in a situation where many individuals are exposed to contamination due to the inhalation of radioactive materials. Assessments of contamination may need to be performed by emergency response personnel in order to triage the potentially exposed public. The feasibility of using readily available standard 2x2-inch sodium-iodide detectors to determine the committed effective dose to a patient following the inhalation of a radionuclide has been investigated. The 2x2-NaI(Tl) detector was modeled using the Monte Carlo simulation code, MCNP-5, and was validated via a series of experimental benchmark measurements using a polymethyl methacrylate (PMMA) slab phantom. Such validation was essential in reproducing an accurate detector response. Upon verification of the detector model, six anthropomorphic phantoms, based on the MIRD-V phantoms, were modeled with nuclides distributed to simulate inhaled contamination. The nuclides assessed included Am-241, Co-60, Cs-137, I-131, and Ir-192. Detectors were placed at four positions on the phantoms: anterior right torso, posterior right torso, anterior neck, and lateral left thigh. The detected count-rate varied with respect to detector position, and the optimal detector location was determined on the body. The triage threshold for contamination was set at an action level of 250-mSv of intake. Time dependent biokinetic modeling was employed to determine the source distribution and activity in the body as a function of post-inhalation time. The detector response was determined as a function of count-rate per becquerel of activity at initial intake. This was converted to count-rate per 250-mSv intake for triage use by first responders operating the detector to facilitate triage decisions of contamination level. A set of procedure sheets for use by first responders was compiled for each of the phantoms and nuclides investigated.
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Etude de l'explosion de mélanges diphasiques : hydrogène et poussières / Two-phase mixtures explosion study : hydrogen and dustsSabard, Jérémy 06 September 2013 (has links)
Cette étude s’inscrit dans le cadre de la sûreté de l’installation ITER. En effet, des études d’accidentologie concernant cette installation ont permis de mettre à jour un risque d’explosion de mélanges à base d’hydrogène et de poussières. L’objectif de la thèse est d’acquérir les données fondamentales caractérisant l’explosion de ces mélanges diphasiques permettant ainsi d’évaluer les pressions générées par une éventuelle explosion des poussières qu’elle soit concomitante on non à celle de l’hydrogène. Pour se faire, des expériences, en bombe sphérique, ont été réalisées concernant des mélanges gazeux hydrogène - oxygène - azote. Les expériences ont été accomplies pour des températures de 303 et 343 K et des pressions de 50 et 100 kPa pour différentes concentrations en hydrogène et différents rapports N2/O2 dans le mélange. Les paramètres de caractérisation de l’explosion de ces mélanges ont été déterminés tels que la pression maximale de combustion (PMAX), l’indice de déflagration (KG ou KST), le temps de combustion (tC), la vitesse fondamentale de flamme (SL°) et la longueur de Markstein (LB). Une modélisation cinétique de la vitesse de flamme utilisant le code COSILAB a été réalisée, permettant de déduire la vitesse fondamentale de flamme sur la base de trois mécanismes cinétiques détaillés de la littérature. Celle-ci a permis l’évaluation de l’énergie d’activation globale sur la base du modèle cinétique présentant le meilleur accord avec l’expérience. De plus des calculs thermodynamiques à l’équilibre ont été réalisés afin de comparer les pressions maximales de combustion aux valeurs théoriques. Pour les mélanges diphasiques, un nouveau système d’introduction des poussières a été mis en place et des expériences caractérisant les paramètres d’explosion de ces mélanges ont été réalisées dans la bombe sphérique. Celles-ci ont permis de mettre en exergue le fait qu’une explosion de poussières, sous certaines conditions peut-être concomitante à une explosion d’hydrogène. / The context of the study is the safety of the ITER installation. Indeed, studies have shown that it exists a risk for two-phase mixtures of hydrogen and dust can explode and create a safety risk for the ITER installation. This aims to obtain the fundamental data which characterize the explosion of these mixtures and to evaluate the pressure loads they can generate. To do so, experiments in spherical bomb have been carried out for hydrogen - oxygen - nitrogen mixtures at two initial temperatures (303 and 343 K) and pressures (50 and 100 kPa) for different hydrogen concentrations and different N2/O2 ratios. Explosion parameters like maximum combustion pressures (PMAX), deflagration indexes (KG or KST), combustion times (tC), fundamental flame speeds (SL°) and Markstein lengths have been determined. A kinetic modelling of the flame speed, using the COSILAB software was performed based on three detailed kinetic models available in the literature and allowed the calculation of the global activation energy on the basis of the kinetic model which showed the best agreement with the experimental data. Moreover equilibrium calculations were achieved to compare PMAX to the theoretical values. For two-phase mixtures, a new introduction device was tested and set up and experiments characterizing the explosions parameters of the two-phase mixtures have been performed in the spherical bomb. They were able to stress out the fact that, under some circumstances, dust explosion can be concomitant to a hydrogen explosion.
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Porovnání radiologických a chemických zbraní v rámci jejich použití při teroristických útocích proti civilnímu obyvatelstvu / Comparison of radiological and chemical weapons in the context of their use in terrorist attacks against civiliansGUBRICKÝ, Václav January 2010 (has links)
The thesis is focused on radiological and chemical weapons in the context of their use in terrorist attacks against the civilian population in relation to rescue and clean up operations of the Integrated Rescue System (IRS) of the Czech Republic. The objective of the thesis is to specify the terms of radiological and chemical weapons, to assess potential negative consequences of their use with the emphasis on the threat to life and health of the population, to evaluate the economic impact on society and to compare the IRS activities during the immediate intervention carried out after a terrorist attack. The topic is dealt with based on the research and the analysis of rules of law in force regulating activities of the IRS components in these major incidents and also of documents of the IAEA (International Atomic Energy Agency) and other works focused on the misuse of radioactive and chemical agents in terrorist attacks. Severity and complexity of the issue is illustrated by information given on the radiological accident in Goiana in Brazil, sarin attacks of the Japanese sect Óm šinrikjó and consequences of the model example of the use of radionuclide 137Cs. In the thesis the current methodology on which the IRS components operate in such emergencies is analyzed, and some aspects that are subject of the set of type activities, worked out by the Civil Emergency Planning Committee and DG Fire Rescue Service of the CR, which may become weak points during a real action of the IRS, are pointed out. One of major issues analyzed in this study is comparison of radiological and chemical attacks with the focus on the initial phase of the intervention of the IRS components. Presentation of differences in individual activities of the IRS components in such interventions can contribute significantly to understanding and subsequently managing the activities carried out by the IRS components in these major incidents.
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Composés polyazotés dérivés d’hydrazines : synthèse, caractérisation et modélisation quantique des performances énergétiques / Polynitrogen compounds derived from hydrazines : synthesis, characterization and quantum modeling of energetic performancesForquet, Valérian 19 December 2012 (has links)
La synthèse de composés énergétiques fortement azotés, à partir des réactifs et des processusissus de la chimie des hydrazines, a permis une nouvelle approche de composés de type HEDM(High Energy Density Materials) pour la propulsion spatiale. En effet, la formation de diazote(N−−−N) à partir d’une liaison N−−N libère de grandes quantités d’énergie, et davantage depuis uneliaison N−N. L’amination de la diméthylhydrazine dissymétrique (UDMH) a conduit à un sel de2,2-diméthyltriazanium, possédant trois atomes d’azote reliés uniquement par des liaisons sigma.L’anion inorganique de départ a ensuite été échangé avec des anions énergétiques à plus haut tauxd’azote — 5-aminotétrazolate, 5-nitrotétrazolate, 5,5’-azobistétrazolate, azoture, nitroformiate etdinitroamidure. Pour des raisons de sécurité, l’échange d’ions impliquant l’anion azoture a étéréalisé par électrodialyse et la sensibilité à l’impact ainsi qu’à la friction de ces sels a été évaluéeselon les normes en vigueur. L’analyse des composés les plus riches en azote par calorimétrie decombustion a permis de déterminer leurs enthalpies de formation de manière fiable. Ces dernièresont ensuite été modélisées par des méthodes de chimie quantique et comparées aux procéduresreportées dans la littérature, dont les aspects théoriques ont été discutés. La procédure conduisantaux enthalpies de formation en meilleure adéquation avec les valeurs expérimentales a étéidentifiée ; sa précision excède d’ailleurs celle de résultats récents d’équipes reconnues. Ainsi, lesmoyens mis en place dans le cadre de cette thèse permettront de progresser plus efficacementdans cette nouvelle thématique au laboratoire. / High nitrogen content energetic compounds, envisioned as a first step towards High EnergyDensity Materials (HEDM) for space propulsion, were prepared from hydrazine derivatives. Indeed,the formation of nitrogen gas (N−−−N) from an N−−N bond yields a lot of energy and even morefrom an N−N bond. Hence, an amination reaction on unsymmetrical dimethylhydrazine (UDMH)yielded a 2,2-dimethyltriazanium salt, containing three consecutive single-bonded nitrogen atoms.The initial inorganic anion was then exchanged with the following nitrogen-rich anions in order toyield energetic salts: 5-aminotetrazolate, 5-nitrotetrazolate, 5,5’-azobistetrazolate, azide, nitroformateand dinitramide. For safety reasons, the ion metathesis of the azide salt was conductedby electrodialysis and the sensitivities of all compounds towards both impact and friction wereevaluated in accordance with standard procedures. Reliable heats of formation of the compoundswith the highest nitrogen content were obtained by oxygen bomb calorimetry. These values werethen computed with quantum mechanical methods and compared with known procedures reportedin the literature, whose theoretical backgrounds have been discussed. Consequently, theprocedure resulting in the best match between calculated and experimental heats of formation wasidentified. The precision of the method used herein exceeds that of recent results from renownedresearch groups in this field. Thus, the various techniques introduced during the course of thiswork will enable our laboratory to progress more efficiently in this area of research.
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Reading in the park : A new context for the library of Kungsholmen / Parkläsning : En ny plats för Kungsholmens bibliotekEvensen, Fredrik January 2014 (has links)
My project is about the library of Kungsholmen, spaces for interaction and theactivity of reading. In the beginning of the 20th century The public libraries of Sweden was born out of the idea that the “people” needed to be educated. Collective public education became the instrument by which the people would become more involved in creating a modern society. Throughout the 20th century the library grew stronger and together with the idea of “Folkhemmet” they turned into strong and distinctive symbols of the collective civic value and democracy. The access of knowledge and a built environment for everyone is two of the fundamental values when speaking of the library. At Kungsholmens the library is cramped away within the rumbling noise of the intersection of SanktEriksgatan / Drottningholmsvägen. Here you find the entrance to the third most visited library in the Stockholm region with about 2000 visitors/day. There has been a decision made for transforming the property that the library is a part of into a new large Shopping mall. As the early plans show, one of the entrances to the mall will cut straight through the library space leaving the visitors to pass through the shopping mall when moving within the library space. The library holds a tempo and carries a certain atmosphere, an atmosphere that I find difficult to combine within a shopping mall environment. But also thefundamental thought that Valfrid Palmgren had, the author of the public library inSweden in the beginning of the 20th century, that the library was to be free from external and commercial forces. I therefor find it somehow problematic having to pass through a shopping mall to be able to access the public space of the library. I therefor propose a new site and a new context for the library of Kungsholmen. / Biblioteket på Kungsholmen är på väg att bli en del av ett nytt shoppingcenter. Som de tidiga planerna visade skulle en av entreerna till gallerian skära rakt genom bibliotekets verksamhet. Man skulle därför vara tvungen att röra sig genom gallerian då man tog sig inom bibliotekets sfär. Det går emot den grundläggande tanken som Valfrid Palmgren hade i början av 1900 talet då grunden till våra folkbibliotek idag lades - Biblioteket ska stå fri från komersiella påtryckningar och tankar, då som nu. Jag föreslår en alternativ plats för Kungsholmens bibliotek i direkt kontakt med ett nytt offentligt torg. Platsen är nuvarande Brandstationen vid Hantverkargatan.
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Baskická teroristická organizace ETA - její aktivita po roce 2004, metody boje, vnitřní struktura a perspektivy dalšího vývoje / Basque terrorist organization ETA - its activity since 2004, tactics, internal structure and future perspectives of developmentHašková, Adéla January 2012 (has links)
The master thesis "Basque terrorist organization ETA - its activity since 2004, tactics, internal structure and future perspectives of development" deals with the analysis of development of the Basque terrorist organization ETA after 2004, when the islamic fundamentalists attacked Madrid. The first part of this thesis briefly presents basic theoretical principles of terrorism. The second part is focused on the history of ETA and its development from the very beginning till the year 2004. The third and the main part analyses the current development of ETA and the modification of its structure and strategy and also the counter- terrorist provisions, which have been taken by the Spanish state in order to paralyse the organization. All kinds of aspects which had and still have an influence on this issue had been taken into account - the changes of the internal structure of ETA and its financing, the changes in legislation or the changes in security forces strategy. A special chapter concentrates on the analysis of the strategic importance of ceasefire and the negotiations with the government.
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"Green Cheese" and "the Moon": Jimmy Carter, Ronald Reagan, and the EuromissilesGriffith, Luke January 2018 (has links)
No description available.
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