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Dissertations / Theses on the topic 'Mass'
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Hudson, Michael John. "The nearby universe : maps, mass and motion." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240968.
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Boyce, Cary 1955. "Mass." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc1038770/.
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This thesis is a musical setting of the Ordinary of the Roman Catholic Mass: Kyrie, Gloria, Credo, Sanctus, and Agnus Dei. It is scored for a soprano soloist, a four-part chorus (SATB), percussion requiring one player (orchestral bells, vibraphone, and chimes), piano, and pipe organ. The text is taken from the traditional Latin and its English translation, the Greek (in the case of "Kyrie eleison") and verse taken from scripture--John 1:1, John 1:5, and Revelation 1:17-18--as translated in the Revised Standard Version Bible. These verses are woven into the musical fabric of the Kyrie and the Gloria and are frequently overlayed with the text of the Mass itself. The text is treated freely with some cyclic treatment of textual and thematic material.
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Rothe, Eric V. (Eric Vaughn). "Mass." Thesis, North Texas State University, 1985. https://digital.library.unt.edu/ark:/67531/metadc504172/.
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Mass is written for large mixed choruswind ensemble consisting of woodwind quartet (flute, oboe, Bb clarinet, and bassoon), brass quintet (two Bb trumpets, F horn, trombone, bass trombone), and recorded digital synthesizer. This setting of the Ordinary is in Latin and includes the Kyrie, Gloria, Credo, Sanctus, and Agnus Dei. The duration of the work is approximately twenty-seven minutes.
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Stieger, Daniel. "Mass customization oder mass confusion wie die Mass-customization-Strategie die Konsumenten verwirrt." Saarbrücken VDM Verlag Dr. Müller, 2007. http://d-nb.info/98772259X/04.
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Myhra, Håkon. "Mass-scenens Intertekstualitet : Mass-scener som intertekstuelt fenomen." Thesis, Karlstad University, Faculty of Arts and Education, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-619.
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The digital evolution in the film industry has opened possibilities that was only to blockbusters before the digital age. I am talking about mass-scenes. Huge scenes with hordes of people often in huge battlefields. This was earlier in film history an extremly costly undertaking for the filmindustry and was a major reason why the large studio systems in Hollywood collapsed in the 60s. Now we can enjoy large scale battles created with CGI without costly extras, costumes and props. It’s all made with the computer and with ’blue screen’ technology. Is it possible to track the mass-scene back to some sort of origin or at least to who that defined the mass-scene ? If we look closer at mass-scenes used in contemporary movies then a clear pattern often emerges. These scenes can often be traced back to especially two propaganda films from the late 30s. Triumph des Willens by Leni Riefenstahl and Alexander Nevsky by Sergei M. Eisenstein. Of course there are others, but these two stands out from the others regarding mass-scenes. My opinion is that these two classic propaganda films have defined the mass-scenes as we have come to see and understand them in many comtemporary films from Star Wars to Lord Of The Rings.
In this thesis I will try to explore the usage of mass-scenes in comtemporary films and hopefully uncover the strong intertextual ties to Triumph des Willens and Alexander Nevsky.
I will also attempt to define the mass-scene and it’s usage in contemporary film.
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Pine, Buddie Joseph. "Paradigm shift--from mass production to mass customization." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13375.
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Kobayashi, Akira. "Numerical Modeling of Mass Transport in Rock Mass." Kyoto University, 1992. http://hdl.handle.net/2433/74607.
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Radovich, Tom. "Critical Mass." Digital Commons at Loyola Marymount University and Loyola Law School, 2018. https://digitalcommons.lmu.edu/etd/494.
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Atkins, Brad Matthew. "Mars Precision Entry Vehicle Guidance Using Internal Moving Mass Actuators." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/50648.
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Many landing sites of scientific interest on Mars including most of the Southern Hemisphere at elevations above 2km Mars Orbiter Laser Altimeter reference are inaccessible due to current limitations in precision entry guidance and payload deceleration. Precision guidance and large payload deceleration is challenging due to the thin Martian atmosphere, large changes in free stream conditions during entry, and aerothermal and aerodynamic instability concerns associated with control systems with direct external flow field interaction. Such risks have descoped past Mars missions to unguided entry with the exception of Mars Science Laboratory's (MSL) bank angle guidance. Consequently, prior to MSL landing ellipses were on the order of 100's of km. MSL has approached the upper limit of payload deceleration capability for rigid, blunt body sphere cone aeroshells used on all successful Mars entry missions. Hypersonic Inflatable Aerodynamic Decelerators (HIADS) are in development for larger payload deceleration capability through inflated aeroshell diameters greater than rigid aeroshells constrained by the launch rocket diameter, but to date there has been limited dynamics, control, and guidance development for their use on future missions.
This dissertation develops internal moving mass actuator (IMMA) control systems for improving Mars precision entry guidance of rigid capsules and demonstrating precision guidance capability for HIADs. IMMAs provide vehicle control moments without direct interaction with the external flow field and can increase payload mass delivered through reducing propellant mass for control and using portions of the payload for the IMMAs. Dynamics models for entry vehicles with rotation and translation IMMAs are developed. IMMA control systems using the models are developed for two NASA vehicle types: a 2.65 m, 602 kg Mars Phoenix-sized entry capsule and an 8.3 m, 5.9 metric ton HIAD approaching payload requirements for robotic precursor missions for future human missions. Linear Quadratic controllers with integral action for guidance command tracking are developed for translation and rotation IMMA configurations. Angle of attack and sideslip guidance laws are developed as an alternative to bank angle guidance for decoupling range and cross-range control for improved precision entry guidance. A new variant of the Apollo Earth return terminal guidance algorithm is implemented to provide the closed-loop angle of attack range control commands.
Nonlinear simulations of the entire 8 degree of freedom closed-loop systems demonstrate precision guidance to nominal trajectories and final targets for off-nominal initial entry conditions for flight path angle, range, cross-range, speed and attitude. Mechanical power studies for IMMA motion show rotation IMMA require less total mechanical power than translation actuators, but both systems have low nominal mechanical power requirements (below 100 Watts). Precision guidance for both systems to terminal targets greater than 38 km down-range from an open-loop ballistic entry is shown for low mechanical power, low CM displacement, (< 4.5 in) and at low internal velocities (< 2 in/s) over significant dynamic pressure changes. The collective precision guidance results and low mechanical power requirements show IMMA based entry guidance control systems constitute a promising alternative to thruster based control systems for future Mars landers.Ph. D.
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Stolte, Andrea. "Mass functions and mass segregation in young starburst clusters." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968318142.
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Garlie, Todd Norman. "Stature, mass, and body mass index of Canadian children /." *McMaster only, 2000.
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Yamada, Ryūsaku. "'Debate on mass society' in Japan : class, mass, citizen." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251219.
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Chaicharoen, Kittisak. "Mass and Tandem Mass Spectrometric Studies on Synthetic Polymers." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1217533390.
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Pascucci, I., L. Testi, G. J. Herczeg, F. Long, C. F. Manara, N. Hendler, G. D. Mulders, et al. "A STEEPER THAN LINEAR DISK MASS–STELLAR MASS SCALING RELATION." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622163.
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The disk mass is among the most important input parameter for every planet formation model to determine the number and masses of the planets that can form. We present an ALMA 887 mu m survey of the disk population around objects from similar to 2 to 0.03 M-circle dot in the nearby similar to 2 Myr old Chamaeleon I star-forming region. We detect thermal dust emission from 66 out of 93 disks, spatially resolve 34 of them, and identify two disks with large dust cavities of about 45 au in radius. Assuming isothermal and optically thin emission, we convert the 887 mu m flux densities into dust disk masses, hereafter M-dust. We find that the M-dust-M* relation is steeper than linear and of the form M-dust proportional to (M*)(1.3-1.9), where the range in the power-law index reflects two extremes of the possible relation between the average dust temperature and stellar luminosity. By reanalyzing all millimeter data available for nearby regions in a self-consistent way, we show that the 1-3 Myr old regions of Taurus, Lupus, and Chamaeleon. I share the same M-dust-M* relation, while the 10 Myr old Upper. Sco association has a steeper relation. Theoretical models of grain growth, drift, and fragmentation reproduce this trend and suggest that disks are in the fragmentation-limited regime. In this regime millimeter grains will be located closer in around lower-mass stars, a prediction that can be tested with deeper and higher spatial resolution ALMA observations.
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Kostrzewa, Bartosz. "Maximally twisted mass lattice QCD at the physical pion mass." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2017. http://dx.doi.org/10.18452/17733.
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In der Gitterquantenchromodynamik sind der Einsatz von unphysikalisch großen Quarkmassen und die Extrapolation von Ergebnissen zu physikalischen Massen signifikante systematische Fehlerquellen. In dieser Arbeit wird die praktische Durchführbarkeit numerischer Simulationen der Quantenchromodynamik mit physikalisch leichten up und down Quarkmassen unter Verwendung der Wilson twisted mass Diskretisierung untersucht. Simulationen im Regime physikalisch leichter Quarkmassen sind jedoch einerseits numerisch sehr aufwendig, können andererseits aber auch durch das Auftreten großer Diskretisierungsartefakte nicht praktikabel sein. Anhand von Simulationen mit massendegenerierten dynamischen up und down Quarks wird dargestellt dass die Erweiterung der twisted mass Fermionwirkung durch den Sheikholeslami-Wohlert Term es ermöglicht physikalisch leichte Quarkmassen zu erreichen. Es wird gezeigt, dass die Simulationen stabil sind und dass die Parameter der diskretisierten Theorie so gewählt werden können, dass das geladene Pion seine physikalische Masse annimmt. Ferner wird dargestellt, dass auch die Parameter für eine Simulation mit dynamischen massendegenerierten up und down quarks sowie nichtdegenerierten strange und charm Quarks schrittweise auf ihre physkalischen Werte gesetzt werden können. Um das Verhalten von Observablen bei physikalischer Quarkmasse zu untersuchen, werden Massen und Zerfallskonstanten von pseudoskalaren Mesonen mit up, down sowie strange und charm Valenzquarks berechnet. Die Ergebnisse stimmen größtenteils überein mit den phänomenologischen Werten, obwohl weder Kontinuumslimes noch die Extrapolation zu unendlichem Volumen durchgeführt werden. Renormierte leichte, strange und charm Quarkmassen werden über Interpolationen in hadronischen Observablen berechnet und stimmen ebenso größtenteils mit phänomenologischen Werten und anderen Ergebnissen aus der Gitter-QCD überein.In computer simulations of Lattice Quantum Chromodynamics, the usage of unphysically large quark masses and the subsequent extrapolation of results to the physical value of the quark masses are major sources of systematic uncertainty. In this thesis, the feasibility and practicality of numerical simulations of Quantum Chromodynamics with physically light up and down quarks using the Wilson twisted mass quark discretisation are explored. Working in this regime is complicated firstly by the numerical expense of these simulations and secondly by the presence of potentially large lattice artefacts. The twisted mass discretisation is affected by an unphysical mass difference between the charged and neutral pions, rendering simulations at the physical charged pion mass infeasible if this mass splitting is too large. With the aim of reducing it, the Sheikholeslami-Wohlert term is added to the twisted mass fermion action and simulations with mass degenerate up and down quarks are then performed as a proof of concept. It is demonstrated that these simulations are stable and that the parameters of the lattice theory can be successfully tuned to correspond to the physical charged pion mass. Subsequently, the parameter tuning for simulations with mass degenerate up and down quarks as well as strange and charm quarks is explored and it is shown that it can be carried out in steps. As benchmark observables, the masses and decay constants of pseudoscalar mesons with light, strange and charm valence quarks are calculated and seen to largely reproduce their phenomenological values, even though continuum and infinite volume extrapolations are not performed. Light, strange and charm quark mass estimates are determined based on this data and also seen to coincide with phenomenological and other lattice determinations.
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Ismail, Abd Khamim. "MEMS mass sensor." Thesis, University of Newcastle Upon Tyne, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430353.
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Růžičková, Michaela. "Leonard Bernstein: MASS." Master's thesis, Akademie múzických umění v Praze.Hudební a taneční fakulta. Knihovna, 2016. http://www.nusl.cz/ntk/nusl-253942.
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This thesis analyzes in detail the work of Leonard Bernstein: MASS. The analysis covers both the theoretical and formal point of view as well as the interpretation issues, while focusing specifically on the issue of interpreting the multi-genre musical work and its definition.
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Raus, Dina <1992>. "The mass customization." Master's Degree Thesis, Università Ca' Foscari Venezia, 2019. http://hdl.handle.net/10579/14221.
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La mia tesi verterà sull'argomento della Personalizzazione del prodotto, di come si è arrivato a ciò nel corso degli anni, di come si sono evoluti i tempi e si sia creata l'esigenza di adattare il prodotto alle esigenze del cliente. Inizierò con un confronto fra fra la produzione di massa e personalizzazione di massa, di diversi diti di personalizzazione che oggi sono sempre più presenti nella nostra quotidianità. In fine parlerò del caso specifico della Bortolin Kemo SPA, azienda in cui ho avuto modo di fare uno stage e in cui lavoro, il cui business verte appunto sulla capacità di creare macchine ad hoc per il cliente.
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Lemire, Sharon Warford. "Rigorous analytical applications of liquid secondary ion mass spectrometry/mass spectrometry." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/30026.
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Pozzo, Monica. "The effect of high-mass stars on low-mass star formation." Thesis, Keele University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366445.
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Dabney, David E. "Analysis of Synthetic Polymers by Mass Spectrometry and Tandem Mass Spectrometry." University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1259021862.
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Monna, A., S. Seitz, I. Balestra, P. Rosati, C. Grillo, A. Halkola, S. H. Suyu, et al. "Precise strong lensing mass profile of the CLASH galaxy cluster MACS 2129." OXFORD UNIV PRESS, 2017. http://hdl.handle.net/10150/624505.
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We present a detailed strong lensing (SL) mass reconstruction of the core of the galaxy cluster MACS J2129.4-0741 (z(cl) = 0.589) obtained by combining high-resolution Hubble Space Telescope photometry from the CLASH (Cluster Lensing And Supernovae survey with Hubble) survey with new spectroscopic observations from the CLASH-VLT (Very Large Telescope) survey. A background bright red passive galaxy at z(sp) = 1.36, sextuply lensed in the cluster core, has four radial lensed images located over the three central cluster members. Further 19 background lensed galaxies are spectroscopically confirmed by our VLT survey, including 3 additional multiple systems. A total of 31 multiple images are used in the lensing analysis. This allows us to trace with high precision the total mass profile of the cluster in its very inner region (R < 100 kpc). Our final lensing mass model reproduces the multiple images systems identified in the cluster core with high accuracy of 0.4 arcsec. This translates to a high-precision mass reconstruction of MACS 2129, which is constrained at a level of 2 per cent. The cluster has Einstein parameter Theta(E) = (29 +/- 4) arcsec and a projected total mass of M-tot (< Theta(E)) = (1.35 +/- 0.03) x 10(14) M-circle dot within such radius. Together with the cluster mass profile, we provide here also the complete spectroscopic data set for the cluster members and lensed images measured with VLT/Visible Multi-Object Spectrograph within the CLASH-VLT survey.
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Ristov, Pero, and Ristova Ana Trpeska. "WEB-BASED PRODUCT CONFIGURATION FOR MASS CUSTOMIZATION : Towards developing mass customization strategy." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-15576.
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The increasing demand towards products and services that perfectly matches the customer needs is evident, so the manufacturing trends are aiming to produce small unit of customized product in large total volumes. The advances in manufacturing and information technologies provided great opportunities to achieve cost-effective mass customization. The purpose of this study was to have a holistic view on under-standing how entrepreneurs in small companies employ and effectively manage mass customization realization. The focus was placed in identifying what are the major factors that influence successful mass customization, how available technologies are enabling this process and how companies achieve value co-creation with the customers. In order to study the practical implementation of mass customization four case studies have been conducted. The information gathered was categorized and the preliminary theoretical framework was used as a template to compare the empirical results. The results show that every strategy for mass customization has to be customizes according to the particular product/service, market, customers, and the available technology for cost efficient implementation of mass customization. In a mass customization system value co-creation is achieved by direct customer integration and is benefiting from economies of integration. The challenge is to balance the system to the right degree, so socially and technologically efficient environment can bring higher value for the customers and better business opportunities for the companies.This Master Thesis project has been carried out as part of "Production Development and Management" Program at JTH and "Information Technology and Management" program at JIBS.
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Rodzinyak, Kristyn. "An astrobiological exploration of mass dependent and mass independent sulphur isotope fractionation." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114265.
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In this thesis, I examined multiple sulfur isotopes in two different systems: mass dependent fractionation and mass independent fractionation. Mass dependent sulfur isotopes elucidate low-temperature oxidative processes from pyrite nodules within Miocene lake sediments found in the Haughton impact structure on Devon Island, Nunavut. Mass independent samples are investigated for lithological and geographical controls on the pattern of 33S and 36S anomalies in Mesoarchaean samples from Northwestern Ontario. In mass dependent systems, the distribution of isotopes can be predicted based on the differences in mass of the various isotopes. Published studies of abiotic and biotic sulfur oxidation show negligible fractionation between starting sulfide and resulting sulfates. Pyrite nodules are being oxidized in a polar desert environment to a variety of sulfates including gypsum, jarosite, and schwertmannite. Within individual nodules, fractionation between sulfate and sulfide range from -10.1 to +17.9 ‰. In addition, a two-component mixing between pyrite and bedrock sulfates divides the nodules into three types. The first two are explained by conventional oxidation and mixing; however, most samples cannot be described solely through mixing or oxidation. Measuring large fractionations in sulfide oxidation has implications for the study of 'biosignatures' such that an oxidizing environment, for example the surface of Mars, would be incompatible with the preservation of 'biosignatures'. In samples older than approximately 2.45 billion years, mass independent fractionation is observed in rock samples. These anomalous enrichments or depletions in 33S cannot be predicted solely on mass differences; rather they are attributed to photochemical reactions of SO2 in an oxygen poor atmosphere. Within the Mesoarchaean the magnitude of these anomalous 33S measurements are considerably diminished compared to contiguous time periods. Previous work has focused on changes in atmospheric chemistry to explain these minimum values. By looking at samples from Northwestern Ontario, the effect of lithology and geography are tested. In addition, a sulfur isotope database compiles the literature data. The range of multiple sulfur isotope data is extended as compared to the data from South Africa and Australia; however, the magnitude remains small when compared to adjacent time periods. Nevertheless, the isotope systematics of the Mesoarchaean, with this added dataset, follow the Archaean reference array which has previously not been used for the Mesoarchaean samples. Regarding lithology, chemically and biologically precipitated samples show large variation in anomalous 33S whereas clastic rocks remain close to zero.Cette étude se penche sur le comportement des différents isotopes du soufre dans deux systèmes distincts : le fractionnement dépendant de la masse et le fractionnement indépendant de la masse. Les isotopes du soufre dépendants de la masse élucident les procédés oxydants de basse température dans des nodules de pyrite de sédiments lacustres d'âge Miocène trouvés dans la structure d'impact Haughton sur l'Île Devon. Les échantillons indépendants de la masse ont été étudiés afin d'évaluer les contrôles lithologique et géographique sur les anomalies en 33S et 36S d'échantillons Mésoarchéens du nord-ouest de l'Ontario. Pour les systèmes dépendants de la masse, la distribution des isotopes peut être prédite en fonction des différences de masse des isotopes. Les ouvrages publiés traitant de l'oxydation abiotique et biotique du soufre démontrent un fractionnement négligeable entre les sulfites d'origine et les sulfates résultants. Les nodules de pyrite ont été oxydées dans un environnement polaire désertique pour former différents sulfates, comme le gypse, la jarosite, et la schwertmannite. À l'intérieur des nodules, le fractionnement entre sulfates et sulfites varie de -10.1 à +17.9 ‰. De plus, un mélange à deux composants entre la pyrite et les sulfates du substrat rocheux divise les nodules en trois types. Les deux premiers sont expliqués par des procédés d'oxydation et de mélange conventionnels, bien que la plupart des échantillons ne peuvent être décrits uniquement en termes de mélange ou d'oxydation. La mesure de grands fractionnements associés à l'oxydation des sulfites a des implications pour l'étude de « biosignatures » puisqu'un environnement oxydant, par exemple la surface de Mars, serait incompatible avec la préservation de telles « biosignatures ». Pour les échantillons rocheux vieux de plus de 2.45 milliards d'années, on observe le fractionnement indépendant de la masse. Ces augmentations ou réductions anormales en 33S ne peuvent pas être expliquées seulement par la différence de masse. Celles-ci sont plutôt attribuées aux réactions photochimiques du SO2 dans une atmosphère pauvre en oxygène. Au cours de Mésoarchéen l'ampleur de ces mesures anormales en 33S sont considérablement diminuées en comparaison avec les périodes de temps adjacentes. Les travaux antérieurs se sont concentrés sur les changements de la chimie atmosphérique pour expliquer le minimum. En considérant des échantillons du nord-ouest ontarien, les effets lithologiques et géographiques sont testés. En plus, une base de données des isotopes du soufre compile les données de la littérature. La variation des données sur les multiples isotopes du soufre est étendue en rapport aux données du l'Afrique du Sud et de l'Australie. Par contre, l'amplitude du fractionnement demeure limitée en comparaison aux périodes adjacentes. Toutefois, la systématique isotopique du Mésoarchéen, avec ces données additionnelles, suit les valeurs de référence de l'Archéen alors que celles-ci n'avaient pas été utilisées jusqu'ici pour des échantillons Mésoarchéens. En ce qui concerne les effets lithologiques, les échantillons précipités lors de procédés chimiques et biologiques montrent de grandes variations en 33S anormal alors que les roches clastiques demeurent près de la valeur zéro.
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Goodwin, Lee. "Capillary electrophoresis-mass spectrometry and tandem mass spectrometry studies of ionic agrochemicals." Thesis, University of York, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398906.
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ALVES, MARCELO LIMA. "EFFECT OF ROUGHNESS MEASUREMENT ON THE MASS OF CLASS F2 MASS STANDARDS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=3664@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROA presente dissertação tem como objetivo a avaliação do efeito da medição da rugosidade sobre os valores de medição das massas de padrões de massa classe F2, em conformidade às exigências da Recomendação Internacional R 111 da Organização Internacional de Metrologia Legal (OIML) e às normas ISO/97, referentes ao assunto. O conceito de rugosidade e os parâmetros (Ra - roughness average e Rz - average of the roughness) foram adequadamente caracterizados no contexto da pesquisa desenvolvida. As medições de rugosidade foram realizadas em padrões de massa Classe F2 - 0,02 g, 0,05 g, 0,1g, 0,2 g, 0,5g, 1g, 2g, 5g, 10g, 20g, 50g, 100g, 200g e 500g, pôr meio de um rugosímetro tipo SJ 400. Empregou-se método convencional com suspeita de retirar diminutas quantidades de matéria do objeto medido. Os padrões de massa Classe F2 - 0,05 g, 0,1g, 0,2 g, 0,5g, 1g, 2g e 5g utilizados foram calibrados antes e depois das medições , por apresentarem os menores erros máximos admissíveis. A seguir, é mostrada a análise estatística dos dados experimentais na medição de rugosidade. Finalmente, foi calculada a incerteza de medição dos resultados experimentais da coleção de padrão de massa Classe F2, bem como a conclusão sobre este trabalho experimental.
The present work has as objective the evaluation of the effect of the roughness measurement on the mass measurement values of F2 class mass standards. The interest is analysing the conformity to the requirements of the International Recommendation R 111 of the International Organization of Legal Metrology (OIML) and to standards ISO/97, referring to the subject. The roughness concept and the parameters, roughness average (Ra.), and average of the roughness (Rz.), were adequately characterized in the context of the developed research. The roughness measurements were carried out with the following F2 class mass standards: 0.02 g, 0.05 g, 0.1 g, 0.2 g, 0.5 g, 1 g, 2 g, 5 g, 10 g, 20 g, 50 g, 100 g, 200 g and 500 g, with the aid of a profilometer SJ 400. The conventional method was used to remove small amounts of substance of the measured object. The used F2 class mass standards, 0.05 g, 0.1g, 0.2 g, 0.5 g, 1 g, 2 g and 5 g, were calibrated before and after the measurements, because they presented the smallest permited maximum errors. The statistical analysis related to the experiments is shown next. Finally, the measurement uncertainty of the experimental results of the standard F2 mass collection was calculated and the conclusions of this study were presented.
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Mahale, Tushar Ramkrishna. "Electron Beam Melting of Advanced Materials and Structures, mass customization, mass personalization." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-11052009-143257/unrestricted/etd.pdf.
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Luhman, Kevin Lee 1971. "Low-mass star formation and the initial mass function in young clusters." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/288884.
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I have used optical and near-infrared spectroscopy and imaging to measure spectral types and luminosities for young (τ < 10 Myr), embedded (Aᵥ = 0-50), low-mass (0.1-1 M(⊙)) stars in three nearby (d < 300 pc) clusters: L1495E, IC 348, and ρ Ophiuchi. In conjunction with theoretical evolutionary tracks, I have derived the star formation history and initial mass function for each stellar population. A large number of brown dwarf candidates have been identified in the photometry, several of which are confirmed through spectroscopy. Finally, I have measured the frequency and survival times of circumstellar disks and investigated the photometric and spectroscopic properties of protostars. In § 2, I apply observational tests to the available sets of evolutionary models for low-mass stars, concluding that the calculations of D'Antona & Mazzitelli are preferred for the range of masses and ages considered here. In § 3 and § 4, I examine in detail the spectroscopic characteristics and substellar nature of two brown dwarf candidates. The study then expands to include the populations within the clusters L1495E (§ 5), IC 348 (§ 6), and ρ Ophiuchi (§ 7). In § 8, I briefly discuss the past, present, and future of scientific research related to this thesis.
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Dye, Simon. "Gravitational lens mass reconstruction." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/27964.
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A highly desirable technique sought after by cosmology is one which enables the accurate mass measurement of rich galaxy clusters. From observations of their abundance and primarily their mass, clusters give strong constraints on the density parameter of the Universe, models of structure formation and normalisation of the power spectrum of density fluctuations. Gravitational lensing provides such a technique. Prevailing over X-ray temperature and virial velocity methods known to be problematic, lensing permits determination of cluster masses independent of dynamical state. This thesis concentrates mainly on the exploitation of the magnification properties of lenses rather than those of shear analysis which relies upon the quantification of galaxy image distortions. Magnification allows absolute mass measurements, breaking the sheet-mass degeneracy experienced by shear. To this extent, a theoretical analysis of the geometrical magnification of angular separations between galaxies lying behind a lensing cluster is performed. This sees application to the cluster Abell 1689 using V and I band observations to select background galaxies based on their V-I colour. The distribution of source number counts in the observed field of view results in the determination of a radial mass profile and a mass map for Abell 1689. This predicts a projected mass interior to 0.24h-1Mpc of M (< 0.24h-1Mpc) = (0.50 ± 0.09) x 1015h-1M. A new method of directly determining accurate, self-consistent lens mass and shear maps in the strong lensing regime from magnification is presented. The method relies upon pixellization of the surface mass density distribution which generates a simple, solvable set of equations. The concept of pixellization is also directed at shear analysis to give rise to a simplified method of application. Through use of cluster models, the method is verified before the magnification data from the colour-selected number counts is input to compute a self-consistent mass map of Abell 1689. The property of lens magnification to amplify observed background source fluxes is investigated. Using an independent set of observations in nine optically chosen filters, photometric redshifts of objects lying in the field of Abell 1689 are calculated. In addition to providing an unambiguous distinction between cluster members, foreground objects and background sources this also enables computation of the source luminosity function. Comparison of this with the distribution of luminosities in an observed offset field quantifies the lens-induced flux magnification to arrive at an independent mass profile measurement of Abell 1689. A projected mass interior to 0.25h-1Mpc of M(< 0.25h-1Mpc) = (0.48 ± 0.16) x 1015h-1M is found.
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McMillan, Donald Calum. "Mass participation user trials." Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3656/.
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This thesis investigates how researchers can take advantage of the rapid adoption of mobile technology that has brought with it transformations in social and cultural practice; the expectations of what computers are, what they can do, and the role of digital objects in everyday life. In particular this thesis presents and discuses the use of new App Store style software distribution methods to reduce the cost, in terms of researcher time and hardware, of recruiting a large group of participants for a trial ‘in the wild’ while increasing the potential diversity of users is becoming an attractive option for researchers pursuing the ubicomp vision. It examines the procedures for running large scale trials with the deployment of three applications released to a combined user base of over 135,000 in such a way as to keep the qualitative detail necessary to inform design while gain- ing the diversity of users for claims of generalisability. More generally, it discusses the results that can be expected from this ‘mass participation’ approach, and the ethical responsibilities they place upon researchers. The contributions of this thesis for mobile HCI show that in large-scale trials, relatively rich qualitative data can be collected along with substantial quantitative data, and that a hybrid trial methodology combining a large- scale deployment with a local trial can be a powerful tool in addressing shortcomings of trials that are either solely local or solely global. This thesis also contributes guidelines for researchers running large-scale user trials that give consideration to the established research norms and practices, in an attempt to strike a new balance between invasiveness and utility.
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Eastough, Daniel James. "Mass Perception in Prehension." Thesis, University of Birmingham, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521945.
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Ferara, Edward J. (Edward Joseph) 1976. "Simulation driven mass customization." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/88888.
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Siaga, Henry T. "Mass nouns in Tshivenda." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50012.
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Thesis (MA)--Stellenbosch University, 2004.ENGLISH ABSTRACT: This study investigates the mass nouns in Tshivenda. The specific mass nouns in each nominal class will then be investigated to see whether they have certain morphological and syntactic features which are different from count nouns. Chapter one is the introduction of this study. It describes the aim, organisation and method of the study. Chapter two is the overview of the literature on mass nouns. It gives overview of the most prominent words on mass nouns in general. Some of the prominent works on this alternation include the following: Pelletier (1979a, 1979b,); Ware (1979), Cartwright (1979), McCawley (1979) Chierchia (1982), Link (1983) and Eschenbach (1993). Chapter three investigates which nouns may be mass nouns, the purpose of the classification of nouns in wordnet, nominal classes in Tshivenda and the morphological and syntactic features of mass and count nouns. Chapter four is the conclusion of the study, the summary as well as investigation into the morphological, syntactic and semantic feature of plurality.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die meervoudige naamwoorde in Tshivenda. Die spesifieke meervoudige naamwoorde sal elkeen in sy normale klas geondersoek word om te sien of hulle sekere morfologiese en sintaktiese eienskappe het, wat nie ooreen stem met tel naamwoorde. Hoofstuk 1 is die inleiding van hierdie studie. Dit beskryf die doelwit, organisasie en metode van die studie. Hoofstuk 2 is ‘n oorsig van die literatuur aangaande meervoudige naamwoorde. Hierdie is ‘n oorsig van die mees prominente meervoudige naamwoorde in die algemeen. Sommige van die prominente werke van hierdie nasie sluit die volgende in: Pelletier 91979a; 1979b), Ware (1979), Cartwright (1979), McCawley (1979), Chierchia (1982), Link (1983) en Eschenbach (1993). Hoofstuk 3 identifiseer meervoudige naamwoorde. Die doel van die klasifikasie van naamwoorde in woordnet, normale klassie in Tshivenda en die morfologiese en sintaktiese eienskappe van meervoudigheid. Hoofstuk 4 is die konklusie van die studie, die opsomming as ook die ondersoek in die morfologiese, sinktaktiese en semantieke eienskappe van meervoudigheid.
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Patching, Robert Steven. "Truth-space mass assignments." Thesis, Loughborough University, 2005. https://dspace.lboro.ac.uk/2134/34119.
Full textAbstract:
The theory of mass assignments allows reasoning using probability families that are either imprecise, incomplete or both. The majority of previous work has been with mass assignments defined upon arbitrary domains. This Thesis concentrates on a neglected specialisation of mass assignments, the truth-space mass assignments defined upon the power set of Booleans. The semantics of truth-space mass assignments and their operators are described, both in relation to general mass assignments and also with other methods of imprecise and incomplete reasoning. New operators are defined for truth-space mass assignments that allow them to be reasoned with in new ways consistent with other logic systems. Alterations are made to existing operators to allow them to act in a more intuitive way. Using the new and altered operators this Thesis allows mass assignment theory to act as a many-valued logic handling imprecise and incomplete truths. This opens up many new topics of research and potential for applying the method to solve problems in a new way.
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Нефедченко, Оксана Іллівна, Оксана Ильинична Нефедченко, Oksana Illivna Nefedchenko, and D. Chernova. "Mass media in Britain." Thesis, Видавництво СумДУ, 2008. http://essuir.sumdu.edu.ua/handle/123456789/16006.
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Naumenko, A., Світлана Віталіївна Подолкова, Светлана Витальевна Подолкова, and Svitlana Vitaliivna Podolkova. "Mass panic and technology." Thesis, Sumy State University, 2020. https://essuir.sumdu.edu.ua/handle/123456789/78077.
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Mass panic is an emotional condition of mass, which characterized by a feeling of uncontrollable fear of a certain danger, which spreads in the process of mass "infection" with a loss of self-control. We can consider mechanisms, causes and consequences of mass panic on the example of October 30, 1938. On that day, a radio play based on H. Wells' book "The War of the Worlds", caused a huge panic among the population of the entire state of New Jersey. Millions of people from different cities fled their homes with fear as they believed that the Martian troops had actually landed on Earth and wanted to capture it.
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Morales, Sabogal Agni Amram. "Tall Mass-Timber Building." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78297.
Full textAbstract:
How can we as design professionals contribute to increase the use of less carbon-intensive materials to build our growing cities?
Cities are experiencing a resurgence in population growth and therefore the building industry ought to attend this demand with sustainable solutions. One way of responding to the growing urban population and increase demand for housing as well as to make efficient use of our limited resources is to increase the density in our cities. Since steel and concrete have high material strengths, we currently use either steel, concrete or composites of them to build skyscrapers. Unfortunately, both of these materials have a large carbon footprint. The design community has the challenge to achieve net-zero emissions buildings by the year 2030, and the efforts now should be focused on using less carbon intensive materials, such as timber.
While cultures around the world have built with wood for centuries, recent technological innovations, such as Cross Laminated Timber (CLT), is allowing for new applications of wood as the main structural material and the potential to use it for large-scale projects. However, as expected with a new building material some constrains have still to be overcome.
For my thesis, I desired to explore this issue through the design of a tall building using mass timber as its main structural material. Engineered timber is here, the future is bright!Master of Architecture
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Yuen, Wei Hao. "Ion imaging mass spectrometry." Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.564395.
Full textAbstract:
This work investigates the applicability of fast detectors to the technique of microscope-mode imaging mass spectrometry. By ionising analyte from a large area of the sample, and projecting the desorbed ions by the use of ion optics through a time-of-flight mass spectrometer onto a two- dimensional detector, time- (and hence mass-) dependent distributions of ions may be imaged. To date, this method of imaging mass spectrometry has been limited by the ability to image only one mass window of interest per experimental cycle, limiting throughput and processing speed. Thus, the alternative microprobe-mode imaging mass spectrometry is currently the dominant method of analysis, with its superior mass resolution. The application of fast detectors to microscope-mode imaging lifts the restriction of the detection of a single mass window per experimental cycle, potentially decreasing acquisition time by a factor of the number of mass peaks of interest. Additional advantages include the reduction of sample damage by laser ablation, and the potential identification of coincident eo-fragments of different masses originating from the same parent molecule. Theoretical calculations and simulations have been performed confirming the suitability of conventional time-of-flight velocity-mapped ion imaging apparatus for imaging mass spectrometry. Only small modifications to the repeller plate and laser beam path, together with the adjustment of the accelerating potential field, were required to convert the apparatus to a wide (7 mm diameter) field-of-view ion microscope. Factors affecting the mass and spatial resolution were investigated with these theoretical calculations, with theoretical calculations predicting a spatial resolution of about 26μm and m/m of 93. Typical experimental data collected from velocity-mapped ion imaging experiments were collected, and characterised in order to provide specifications for a novel time-stamping detector, the Pixel Imaging Mass Spectrometry detector. From these data, the suitability of thresholding and centroiding on the new detector was determined. Initial experiments using desorptionjionisation on silicon and conventional charge-coupled device cameras confirmed the correct spatial-mapping of the apparatus. Matrix-assisted laser desorptionjionisation techniques (MALDI) were used in experiments to determine the spatial and mass resolutions attainable with the apparatus. Experimental spatial resolutions of 14.4 μm and m/m of 60 were found. The better experimental spatial resolution indicates a higher di- rectionality of initial velocities from MALDI desorption than used in the theoretical predictions, while the poorer mass resolution could be attributed to limitations imposed by the use of the phosphor screen. Proof-of-concept experiments using fast-framing cameras and the new time-stamping detectors confirmed the feasibility of multiple mass acquisition in time-of-flight microscope mode ion imaging. Mass-dependent distributions were acquired of different pigment distributions in each experimental cycle. Finally, spatial-mapped images of coronal mouse brain sections were acquired using both conventional and fast detectors. The apparatus was demonstrated to provide accurate spatial distributions with a wide field-of-view, and multiple mass distributions were acquired with each experimental cycle using the new time-stamping detector.
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Lopez, Thomas Matthew. "MAss : singing without gravity /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p9992738.
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Ferrari, Maria Chiara <1980>. "Mass transport in polymers." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1629/1/Ferrari_Maria_Chiara_Tesi.pdf.
Full textAbstract:
The study of mass transport in polymeric membranes has grown in importance due to its potential application in many processes such as separation of gases and vapors, packaging, controlled drug release. The diffusion of a low molecular weight species in a polymer is often accompanied by other phenomena like swelling, reactions, stresses, that have not been investigated in all their aspects yet. Furthermore, novel materials have been developed that include inorganic fillers, reactive functional groups or ions, that make the scenery even more complicated.
The present work focused on the experimental study of systems where the diffusion is accompanied by other processes; suitable models were also developed to describe the particular circumstances in order to understand the underlying concepts and be able to design the performances of the material.
The effect of solvent-induced deformation in polymeric films during sorption processes was studied since the dilation, especially in constrained membranes, can cause the development of stresses and therefore early failures of the material. The bending beam technique was used to test the effects of the dilation and the stress induced in the polymer by penetrant diffusion. A model based on the laminate theory was developed that accounts for the swelling and is able to predict the stress that raise in the material.
The addition of inorganic fillers affects the transport properties of polymeric films. Mixed matrix membranes based on fluorinated, high free volume matrices show attractive performances for separation purposes but there is a need for deeper investigation of the selectivity properties towards gases and vapors. A new procedure based on the NELF model was tested on the experimental data; it allows to predict solubility of every penetrant on the basis of data for one vapor. The method has proved to be useful also for the determination of the diffusion coefficient and for an estimation of the permeability in the composite materials.
Oxygen scavenging systems can overcome lack of barrier properties in common polymers that forbids their application in sensitive applications as food packaging. The final goal of obtaining a membrane almost impermeable to oxygen leads to experimental times out of reach. Hence, a simple model was developed in order to describe the transport of oxygen in a membrane with also reactive groups and analyze the experimental data collected on SBS copolymers that show attractive scavenging capacity. Furthermore, a model for predicting the oxygen barrier behavior of a film formed as a blend of OSP in a common packaging material was built, considering particles capable of reactions with oxygen embedded in a non-reactive matrix.
Perfluorosulphonic acid ionomers (PFSI) are capturing attention due to a high thermal and chemical resistance coupled with very peculiar transport properties, that make them appropriate to be used in fuel cells. The possible effect of different formation procedure was studied together with the swelling due to water sorption since both water uptake and dilation can dramatically affect the fuel cells performances. The water diffusion and sorption was studied with a FTIR-ATR spectrometer that can give deeper information on the bonds between water molecules and the sulphonic hydrophilic groups and, therefore, on the microstructure of the hydrated ionomer.
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Ferrari, Maria Chiara <1980>. "Mass transport in polymers." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1629/.
Full textAbstract:
The study of mass transport in polymeric membranes has grown in importance due to its potential application in many processes such as separation of gases and vapors, packaging, controlled drug release. The diffusion of a low molecular weight species in a polymer is often accompanied by other phenomena like swelling, reactions, stresses, that have not been investigated in all their aspects yet. Furthermore, novel materials have been developed that include inorganic fillers, reactive functional groups or ions, that make the scenery even more complicated.
The present work focused on the experimental study of systems where the diffusion is accompanied by other processes; suitable models were also developed to describe the particular circumstances in order to understand the underlying concepts and be able to design the performances of the material.
The effect of solvent-induced deformation in polymeric films during sorption processes was studied since the dilation, especially in constrained membranes, can cause the development of stresses and therefore early failures of the material. The bending beam technique was used to test the effects of the dilation and the stress induced in the polymer by penetrant diffusion. A model based on the laminate theory was developed that accounts for the swelling and is able to predict the stress that raise in the material.
The addition of inorganic fillers affects the transport properties of polymeric films. Mixed matrix membranes based on fluorinated, high free volume matrices show attractive performances for separation purposes but there is a need for deeper investigation of the selectivity properties towards gases and vapors. A new procedure based on the NELF model was tested on the experimental data; it allows to predict solubility of every penetrant on the basis of data for one vapor. The method has proved to be useful also for the determination of the diffusion coefficient and for an estimation of the permeability in the composite materials.
Oxygen scavenging systems can overcome lack of barrier properties in common polymers that forbids their application in sensitive applications as food packaging. The final goal of obtaining a membrane almost impermeable to oxygen leads to experimental times out of reach. Hence, a simple model was developed in order to describe the transport of oxygen in a membrane with also reactive groups and analyze the experimental data collected on SBS copolymers that show attractive scavenging capacity. Furthermore, a model for predicting the oxygen barrier behavior of a film formed as a blend of OSP in a common packaging material was built, considering particles capable of reactions with oxygen embedded in a non-reactive matrix.
Perfluorosulphonic acid ionomers (PFSI) are capturing attention due to a high thermal and chemical resistance coupled with very peculiar transport properties, that make them appropriate to be used in fuel cells. The possible effect of different formation procedure was studied together with the swelling due to water sorption since both water uptake and dilation can dramatically affect the fuel cells performances. The water diffusion and sorption was studied with a FTIR-ATR spectrometer that can give deeper information on the bonds between water molecules and the sulphonic hydrophilic groups and, therefore, on the microstructure of the hydrated ionomer.
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Fagin, Maxwell H. "Payload mass improvements of supersonic retropropulsive flight for human class missions to Mars." Thesis, Purdue University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10046736.
Full textAbstract:
Supersonic retropropulsion (SRP) is the use of retrorockets to decelerate during atmospheric flight while the vehicle is still traveling in the supersonic/hypersonic flight regime. In the context of Mars exploration, subsonic retropropulsion has a robust flight heritage for terminal landing guidance and control, but all supersonic deceleration has, to date, been performed by non-propulsive (i.e. purely aerodynamic) methods, such as aeroshells and parachutes.
Extending the use of retropropulsion from the subsonic to the supersonic regime has been identified as an enabling technology for high mass humans-to-Mars architectures. However, supersonic retropropulsion still poses significant design and control challenges, stemming mainly from the complex interactions between the hypersonic engine plumes, the oncoming air flow, and the vehicle’s exterior surface. These interactions lead to flow fields that are difficult to model and produce counter intuitive behaviors that are not present in purely propulsive or purely aerodynamic flight.
This study will provide an overview of the work done in the design of SRP systems. Optimal throttle laws for certain trajectories will be derived that leverage aero/propulsive effects to decrease propellant requirements and increase total useful landing mass. A study of the mass savings will be made for a 10 mT reference vehicle based on a propulsive version of the Orion capsule, followed by the 100 mT ellipsoid vehicle assumed by NASA’s Mars Design Reference Architecture.
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Huang, Wenjia. "Direct Mass Measurements and Global Evaluation of Atomic Masses." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS151/document.
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L’évaluation des masses atomiques (Ame), commencée dans les années 1960, est la source la plus fiable d’informations complètes sur les masses atomiques. Elle fournit les meilleures valeurs pour les masses atomiques et les incertitudes associées en évaluant les données expérimentales de désintégration, de réactions et de la spectrométrie de masse. Dans cette thèse, la philosophie et les caractéristiques les plus importantes de l’Ame seront discutées en détail. Les développements les plus récents de l’évaluation, AME2016, tels que l’énergie de liaison moléculaire, la correction d’énergie des mesures par implantation, et la formule relativiste pour le processus de décroissance alpha, seront présentés. Une autre partie de cette thèse concerne l’analyse des données du spectromètre à piège de Penning ISOLTRAP au ISOLDE/CERN. Les nouveaux résultats sont inclus dans l’ajustement global et leurs influences sur les masses existantes sont discutées. La dernière partie de cette thèse porte sur les études des erreurs systématiques du spectromètre de masse à multi-réflexion à temps de vol d’ISOLTRAP, utilisant une source d’ions hors ligne et le faisceau de protons en ligne. A partir de l’analyse des mesures sélectionnées, j’ai trouvé que l’erreur systématique est beaucoup plus faible que les incertitudes statistiques obtenues jusqu’à présentThe Atomic Mass Evaluation (AME), started in the 1960s, is the most reliable source for comprehensive information related to atomic masses. It provides the best values for the atomic masses and their associated uncertainties by evaluating experimental data from decay, reactions, and mass spectrometry. In this thesis, the philosophy and the most important features of the Ame will be discussed in detail. The most recent developments of the latest mass table (AME2016), such as molecular binding energy, energy correction of the implantation measurements, and the relativistic formula for the alpha-decay process, will be presented. Another part of this thesis concerns the data analysis from the Penning-trap spectrometer ISOLTRAP at ISOLDE/CERN. The new results are included in the global adjustment and their influences on the existing masses are discussed. The last part of this thesis is related to the systematic error studies of the ISOLTRAP multi-reflection time-of-flight mass spectrometer, using an off-line ion source and the on-line proton beam. From the analysis of the selected measurements, I found that the systematic error is much smaller than the statistical uncertainties obtained up to now
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Schwartz, Sari D. "Atypical depression, body mass, and left vetricular mass analysis of data from CARDIA /." Download the thesis in PDF, 2005. http://www.lrc.usuhs.mil/dissertations/pdf/Schwartz2005.pdf.
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Thompson, Simon. "Low mass stars, brown dwarfs and the initial mass function in Cepheus OB3b." Thesis, Keele University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288434.
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Cardoso, Catia Vanessa Varejao. "Observational properties of brown dwarfs : the low-mass end of the mass function." Thesis, University of Exeter, 2012. http://hdl.handle.net/10036/3592.
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Brown dwarfs are objects with sub-stellar masses that are unable to sustain hydrogen burning, cooling down through out their lifetimes. This thesis presents two projects, the study of the IMF of the double cluster, h & χ Persei, and the determination of the dynamical masses of the brown dwarf binary, ε Indi Ba, Bb. The study of a cluster’s population distribution gives us the opportunity to study a statistically meaningful population of objects over a wide range of masses (from massive stars to brown dwarfs), with a similar age and chemical composition providing formation and dynamical evolution constraints. h & χ Persei is the largest double cluster known in our galaxy. Using optical and infrared photometric data we have produced the deepest mass function for the system. A study of the radial distribution shows evidence of mass segregation while the mass function shows that these clusters may be suffering from accelerated dynamical evolution due to their interaction, triggering the ejection of brown dwarfs. The physical parameterization of brown dwarfs is reliant on the use of interior and atmospheric models. The study of brown dwarf binaries can provide crucial model independent measurements, especially masses. ε Indi Ba, Bb (spectral types T1 and T6) is the closest known brown dwarf binary to Earth. The brown dwarf binary itself orbits a main sequence star allowing us to constrain the distance, metallicity and age of the system making it possible to break the sub-stellar mass-age-luminosity degeneracy. The relative motion of the brown dwarf binary has been studied with precision astrometry from infrared AO data, allowing the determination of the system mass, 121.16 ± 0.17 ± 1.08 MJup . The individual masses of the binary components were derived from the absolute movement of the binary to be MBa = 68.04±0.94 MJup and MBb = 53.12±0.32 MJup. We concluded that the isochronally-derived masses were underestimating the system mass by ∼ 60%, due to the likely underestimation of the age of the system. The evolutionary models are consistent with the parameters measured observationally if the system has an age ∼ 4 Gyr.
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Berezovskaya, Yana. "Investigation of protein-ion interactions by mass spectrometry and ion mobility mass spectrometry." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7747.
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Protein‐ion interactions play an important role in biological systems. A considerable number of elements (estimated 25 – 30) are essential in higher life forms such as animals and humans, where they are integral part of enzymes involved in plethora of cellular processes. It is difficult to overestimate the importance of thorough understanding of how protein‐ion interplay affects living cell in order to be able to address therapeutic challenges facing humanity. Presented to the reader’s attention is a gas‐phase biophysical analysis of peptides’ and proteins’ interactions with biologically relevant ions (Zn2+ and I–). This investigation provides an insight into conformational changes of peptides and proteins triggered by ions. Mass spectrometry and ion mobility mass spectrometry are used in this work to probe peptide and protein affinities for a range of ions, along with conformational changes that take place as a result of binding. Observation of peptide and protein behaviour in the gas phase can inform the investigator about their behaviour in solution prior to ionisation and transfer from the former into the latter phase. Wherever relevant, the gas‐phase studies are complemented by molecular dynamics simulations and the results are compared to solution phase findings (spectroscopy). Two case studies of protein‐ion interactions are presented in this thesis. Firstly, sequence‐to‐structure relationships in proteins are considered via protein design approach using two synthetic peptide‐based systems. The first system is a synthetic consensus zinc finger sequence (vCP1) that is responsive to zinc: it adopts a zinc finger fold in the presence of Zn2+ by coordinating the metal ion by two cysteines and two histidines. This peptide has been selected as a reference for the zinc‐bound state and a simple model to refine the characterisation method in preparation for analysis of a more sophisticated second system – dual conformational switch. This second system (ZiCop) is designed to adopt either of the two conformations in response to a stimulus: zinc finger or coiled coil. The reversible switch between the two conformational states is controlled by the binding of zinc ion to the peptide. Interactions of both peptide systems with a number of other divalent metal cations (Co2+, Ca2+ and Cu2+) are considered also, and the differences in binding and switching behaviour are discussed. Secondly, protein‐salt interactions are investigated using three proteins (lysozyme, cytochrome c and BPTI) using variable temperature ion mobility mass spectrometry. Ion mobility measurements were carried out on these proteins with helium as the buffer gas at three different drift cell temperatures – ‘ambient’ (300 K), ‘cold’ (260 K) and ‘hot’ (360 K), and their conformational preferences in response to HI binding and temperature are discussed.
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Wills, Rebecca Helen. "High mass accuracy analytical applications of Fourier transform ion cyclotron resonance mass spectrometry." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/60050/.
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The performance capabilities of Fourier transform ion cyclotron resonance (FTICR) mass spectrometry are higher than any other type of mass spectrometer, making this technique suitable for a range of analytical applications. Here, FTICR mass spectrometry has been used for the structural analysis of polyketides and nonribosomal peptides, and in the identification of peptide binding sites of ruthenium(II) arene anticancer complexes. In both these applications, methods have been developed involving complementary tandem mass spectrometry techniques, specifically collision activated dissociation (CAD), electron induced dissociation (EID), and electron capture dissociation. In particular, CAD and EID have been shown to be effective in the structural characterisation of polyketides, with a method developed for distinguishing between two isomers of the polyketide lasalocid A. This method has been optimised and extended for application to non-ribosomal peptides enabling detailed structural information to be obtained with very high accuracy. Using CAD and ECD has enabled the identification of amino acids involved in binding ruthenium(II) complexes. Binding to phenylalanine and glutamic acid was observed in this work for the first time; coordination by histidine and methionine was also observed and is in agreement with previous work. Overall, new methods for highly accurate structural characterisation and binding site identification have been successfully designed and implemented.
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Watson, R. Craig Jr. "Laser-Ionization Time-of-Flight Mass Spectrometry of High Molecular Mass Inorganic Complexes." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/35554.
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Laser-Ionization Time-of-Flight Mass Spectrometry (LI-TOF-MS) is a sophisticated tool for the molecular-weight determination and structural characterization of a variety of molecules. Advances in instrumentation and ionization methods have recently expanded its role in the analysis of high-mass analytes. Large multimetallic complexes, which are efficient solar-energy converters, rely heavily on their chemical structure for optimum operation. Molecular mass determinations of these multimetallic complexes have been problematic due to their lability and high molecular weights.
This thesis describes the characterization of a LI-TOF-MS instrument and confirmation of theoretical time-of-flight mass-separation principles. Several test cases demonstrate the instrument's proper operation and calibration for a wide mass range of analytes. Mass spectral results of three organometallic compounds: i. [Ir(dpp)2Cl2](PF6), ii. {[(bpy)2Ru(dpp)]2IrCl2}(PF6)5, and iii. {[(bpy)2Ru(dpp)]2RuCl2}(PF6)5 under a variety of laser ionization and sample preparation conditions are compared. A complete structural characterization of the monometallic complex, [Ir(dpp)2Cl2](PF6), is presented. The two trimetallic analytes fragmented easily, but significant components of the molecules are successfully identified. After optimizing the ionization and analytical procedure, LI-TOF-MS proved useful in the analysis of high molecular mass metal complexes.
Master of Science
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Liu, Xiumin. "Mass Spectrometry and Tandem Mass Spectrometry Analysis of Polymers and Polymer-Protein Interactions." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1406838246.
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