Dissertations / Theses on the topic 'Co 191'
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1
Vichitphan, Kanit. "Azotobacter vinelandii Nitrogenase: Effect of Amino-Acid Substitutions at the Alpha Gln-191 Residue of the MoFe Protein on Substrate Reduction and CO Inhibition." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/11266.
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The FeMo cofactor is one of two types of prosthetic group found in the larger of the two nitrogenase component proteins, called the MoFe protein, and it is strongly implicated as the substrate binding and reduction site. The glutamine-191 residue in the Alpha-subunit of the MoFe protein of A. vinelandii nitrogenase was targeted for substitution because its side chain is involved in a hydrogen-bond network from one of the terminal carboxylates of the homocitrate component of FeMo cofactor through to the backbone NH of Alpha Gly-61, which is adjacent to Alpha Cys-62, which ligates to the P cluster (the second type of prosthetic group in the MoFe protein).
A variety of altered MoFe proteins produced by the A. vinelandii mutant strains, namely the Alpha Pro-191, Alpha Ser-191, Alpha Thr-191, Alpha His-191, Alpha Glu-191, and Alpha Arg-191 altered MoFe proteins, have been purified to homogeneity and the catalytic properties of these altered MoFe proteins have been compared to those of wild type MoFe protein. Unlike wild type, the six altered MoFe proteins have decreased catalytic activity on substrate reduction and exhibited H2 evolution that was partially inhibited by added CO. Moreover, some of altered MoFe proteins with lower specific activity for the C2H4 production can produce C2H6 from C2H2.
The results from the pH and activity studies indicate that the substitutions on the MoFe protein have an effect on the contribution of the responsible acid-base group(s) involved in proton transfer for H+- and C2H2-reduction. Furthermore, the inhibition by CO of hydrogen evolution by these altered MoFe proteins is likely from a lowering of the rate of both electron and proton transfer to the H+- reduction site(s).
Some altered MoFe proteins but not wild type MoFe protein can produce C2H6 from C2H2. This observation suggested a lower apparent binding affinity for C2H2 and a slower proton transfer to C2H2 reduction with these altered MoFe proteins, which allow the intermediate to stay at the site longer and be further reduced by two electrons and two protons to give C2H6.
These changes in the biochemical properties of these altered MoFe proteins indicate that the Alpha Gln-191 residue is intimately involved in substrate binding and reduction including proton delivery to substrate.Ph. D.
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Whitecross, Angela Frances. "Co-operative Commonwealth or New Jerusalem? : the Co-operative Party and the Labour Party, 1931-1951." Thesis, University of Central Lancashire, 2015. http://clok.uclan.ac.uk/11485/.
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The Co-operative Party, despite representing the largest consumer and social movement in Britain, is systematically overlooked or misunderstood in twentieth century British political historiography. What makes this neglect more surprising is that from 1927 the Co-operative Party had a formal electoral agreement with the Labour Party, the basis of which remains in place today. Through this agreement the two parties agreed to work together to return joint Co-operative-Labour candidates in certain constituencies. This unique political alliance reflected a shared ideological ground between the two parties, united in their aim to displace capitalism with common ownership. However, despite this common aim, the methods through which this would be achieved varied and whilst the Labour Party focused on state ownership as key to the ‘socialist commonwealth’, the Co-operative Party, as the political arm of theco-operative movement embodied the ideal of a‘co-operative commonwealth’ built on the principles of democratic voluntary association. Historians who have addressed the relationship between the Labour Party and the co-operative movement have argued that co-operative methods of ownership were systematically marginalised, overlooked and ignored by the Labour Party, particularly during the 1945 to 1951 period of Labour Government. In this context, this thesis will examine the political relationship between the Co-operative Party and the Labour Party in the broader period from 1931 to 1951. It will argue that both organisational and ideological factors contributed to the invisibility of co-operative methods of ownership in the policies of the Labour Party. Moreover, this will provide an additional perspective to debates regarding the development of the Labour Party during the 1930s and over the future direction of nationalisation post 1945. Despite its marginality the Co-operative Party represented a large body of working class consumers and a significant business organisation, which straddled both the labour movement and co-operative movement. Whilst this thesis agrees that co-operative ideas of ownership remained a minor influence on the Labour Party throughout this period, it will nevertheless argue that Co-operative Party contributions to policy discussions provide an alternative perspective from which a growing recognition of the diversity of influences on the Labour Party can be explored. In doing so this thesis will also provide an original interpretation of the organisational and policy history of the Co-operative Party. This will highlight tensions not only with the Labour Party, but also within the co-operative movement with regards to the function and purpose of the Co-operative Party - and more significantly the role of the co-operative movement in a socialist society.
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Jordan, David John. "Army co-operation missions of the Royal Flying Corps/Royal Air Force 1914 - 1918." Thesis, University of Birmingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487881.
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Tang, Sau Lan. "Dynamics of chemisorption : CO on Ni(111)." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15289.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.
Includes bibliographical references.
by Sau Lan Tang.
Ph.D.
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Cooper, Amy Nicole. "Borrowing Culture: British Music Circulating Libraries and Domestic Musical Practice, 1853-1910." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1707295/.
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In Victorian Britain, music circulating libraries libraries operated by music publishers Novello & Co. and Augener & Co. supported upper- and upper-middle-class patrons in their pursuit of cultural capital that would help them perform their socioeconomic status. Studying these libraries in the context of domestic music-making reveals the economic and social impact of these libraries in the lives of amateur musicians and in the music publishing industry. An analysis of the account books in the Novello Business Archives demonstrates that the direct income that Novello & Co., Ltd.'s Universal Circulating Musical Library generated was negligible at best. Yet the fact that the library continued to be part of the business for over forty years indicates that Novello & Co., Ltd. found it to be profitable in some way. In this case, the library could have helped the publisher to attract customers through branding and advertising, in addition to informing publishing decisions by tracking demand. Catalogs for music circulating libraries, as well as for the publishers who owned them, contain lists of library and publisher inventory and pricing. Studying changes in these catalogs reveals how patrons' tastes changed over time. A case study of violin-piano duets in multiple catalogs confirms a continued preference for continental composers over British composers, and another case study of violin-piano duets by Felix Mendelssohn shows a growing taste for arrangements of pieces originally composed for large ensemble. Changing tastes had an effect not only on what music Victorians performed, but also on what pieces publishers offered, and, ultimately, on works' places in the canon.
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Gurney, Peter James. "The making of co-operative culture in England, 1870-1918." Thesis, University of Sussex, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303026.
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Rhodes, Rita. "International Co-operative Alliance during war and peace 1910-1950." Thesis, Open University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261121.
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Butorac, J. "Femtosecond laser studies of CO and NO on Pd(111)." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1335711/.
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The ultimate goal of any branch of chemistry, including surface chemistry, is to understand the dynamics of reactions. The typical time scale for bond making and breaking is the femtosecond time scale. Femtochemistry has led to enormous progress in the understanding, and even control, of chemical reactions in the gas and solution phases over the past decades. However, a comparable level of sophistication in the analysis of surface chemical reactions has not been achieved due to the complexity of the energy dissipation channels. For this thesis, a new experimental set-up was built with the goal to monitor the femtosecond laser-induced desorption (fs-LID) and femtosecond laser-induced reaction (fs-LIR) of CO and NO co-adsorbed on a Pd(111) surface. In addition, a femtosecond extreme ultraviolet (XUV) source was designed and commissioned. All the femtosecond laser-induced studies were accompanied by temperature programmed desorption (TPD) and reflection absorption infrared spectroscopy (RAIRS). First, fs-LID experiments were performed for pure CO and NO adsorbed on Pd(111) in order to test the apparatus. The CO and NO photodesorption dynamics were compared and the different photoreactivity was explained qualitatively using two theoretical models: electron friction and desorption induced by multiple electronic transitions (DIMET). The power law behaviour was also tested and a new method of fitting proposed. The photodesorption behaviour of CO co-adsorbed with NO on Pd(111) was then studied and compared qualitatively with the photodesorption behaviour of pure CO and NO within the empirical friction model.
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Fang, Min. "Co-composing of sewage sludge with coal fly ash." HKBU Institutional Repository, 1998. http://repository.hkbu.edu.hk/etd_ra/181.
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Peter, Matthias. "Oxygen and CO adsorption on supported Pd nanoparticles and Pd(111)." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/16896.
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Um die Korrelation zwischen Partikelgröße und Reaktivität von Pd Nanopartikeln auf Eisenoxid zu untersuchen wurde die experimentelle Methode Einkristalladsorptionskalorimetrie mit der Präparation von Modellsystemen kombiniert. Da diese Systeme mit mikroskopischen Methoden untersucht wurden, liegen detaillierte strukturelle Informationen vor. Es konnte gezeigt werden, dass die Adsorptionsenergie auf 3.4 nm großen Pd Nanopartikeln um 69 kJ/mol höher ist als auf Pd(111). Dieser Effekt resultiert aus der Änderung des Adsorptionsplatzes von Facettenplätzen auf Pd(111) zu Kantenplätzen auf Pd Nanopartikeln. Die Änderung der Partikelgröße im Bereich 3.4 nm - 1.9 nm führt zu einer Verringerung der Adsorptionsenergie um 70 kJ/mol. Eine Reduktion der Adsorptionsenergie auf kleineren Nanopartikeln wurde auch für CO gemessen. Die Differenz in der Pd-O Bindungsenergie zwischen den verschiedenen Systemen verringert sich bei erhöhter Adsorbatbedeckung. Die Anzahl adsorbierter Sauerstoffatome auf frisch präparierten Pd Nanopartikeln bei 300 K ist um drei bis vier mal höher als die Anzahl an Sauerstoffatomen welche Pd Oberflächenplätze sättigen können. Diese Beobachtung kann mit Sauerstoffdiffusion in die Nanopartikel oder in den Träger erklärt werden. Die Wechselwirkung zwischen Sauerstoff und CO auf Pd(111) und Pd Nanopartikeln verschiedener Größen wurde als Funktion der Bedeckung studiert. Aufgrund der CO-O Wechselwirkung verringert sich die CO Adsorptionsenergie um ~40 kJ/mol auf sauerstoffvorbedeckten Pd(111) und Pd Nanopartikeln der Größen 2.9 nm und 3.4 nm.To determine the correlation between the particle size and the reactivity of Pd nanoparticles, which are supported on iron oxide, the experimental method single crystal adsorption calorimetry has been combined with the preparation of model systems. Detailed structural information on the supported systems is available from previous structural studies. It was found that the oxygen adsorption energy is 69 kJ/mol higher on 3.4 nm sized Pd nanoparticles compared to Pd(111) due to a change of the local adsorption site from threefold hollow to low coordinated sites. A reduction of the particle size in the range 3.4 nm - 1.9 nm was found to lead to a decrease of the adsorption energy by 70 kJ/mol. A reduction of the adsorbate binding energy has also been found for CO. The difference in the Pd-O binding energy between the different systems decreases with increasing coverage. It was demonstrated that the number of adsorbed oxygen atoms on freshly prepared Pd nanoparticles at 300 K is three to four times higher than the amount of oxygen atoms which saturate the Pd surface sites. This observation can be explained with oxygen diffusion either into the nanoparticles or into the support. The interaction between oxygen and CO has been studied on Pd(111) and Pd nanoparticles of different sizes as a function of the coverage. Due to CO-O interaction, the CO adsorption energy is reduced by ~40 kJ/mol on oxygen precovered Pd(111) and Pd nanoparticles of 2.9 nm and 3.4 nm.
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Zhang, Tianfu. "A surface science study of NOx and CO adsorption on Au{111} and Ir/Au{111} surfaces." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614233.
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Woodman, Simon. "A programming system for process co-ordination in virtual organisations." Thesis, University of Newcastle Upon Tyne, 2008. http://hdl.handle.net/10443/121.
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Distributed business applications are increasingly being constructed by composing them from services provided by various online businesses. Typically, this leads to trading partners coming together to form virtual organizations (VOs). Each member of a VO maintains their autonomy, except with respect to their agreed goals. The structure of the Virtual Organisation may contain one dominant organisation who dictates the method of achieving the goals or the members may be considered peers of equal importance. The goals of VOs can be defined by the shared global business processes they contain. To be able to execute these business processes, VOs require a flexible enactment model as there may be no single ‘owner’ of the business process and therefore no natural place to enact the business processes. One solution is centralised enactment using a trusted third party, but in some cases this may not be acceptable (for instance because of security reasons). This thesis will present a programming system that allows centralised as well as distributed enactment where each organisation enacts part of the business process. To achieve distributed enactment we must address the problem of specifying the business process in a manner that is amenable to distribution. The first contribution of this thesis is the presentation of the Task Model, a set of languages and notations for describing workflows that can be enacted in a centralised or decentralised manner. The business processes that we specify will coordinate the services that each organisation owns. The second contribution of this thesis is the presentation of a method of describing the observable behaviour of these services. The language we present, SSDL, provides a flexible and extensible way of describing the messaging behaviour of Web Services. We present a method for checking that a set of services described in SSDL are compatible with each other and also that a workflow interacts with a service in the desired manner. The final contribution of this thesis is the presentation of an abstract architecture and prototype implementation of a decentralised workflow engine. The prototype is able to enact workflows described in the Task Model notation in either a centralised or decentralised scenario.
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Albert, Kelsey Morgan. "Microporous Membrane-based Co-culture of Human Embryonic Stem Cells." VCU Scholars Compass, 2007. http://scholarscompass.vcu.edu/etd_retro/161.
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Transwell inserts with microporous membranes, available from multiple commercial sources, have been widely used for various mammalian cell culture applications, including the reduction of cell culture mixing. In this study, we examined the feasibility and functionality of using this technology for separating human embryonic stem cells (hESCs) from their respective feeder cells. We found that when hESCs were propagated on transwell inserts positioned directly above feeder cells grown in a separate dish, the hESCs could be maintained in an undifferentiated state for over 10 passages with no change in their basic pluripotent characteristics. In parallel with our transwell insert experiments, we also evaluated the ability of a new defined, xeno-free medium, HEScGRO, to enhance the animal-free characteristics of the transwell insert-based culture system. Results from our studies demonstrate that HEScGRO medium assists in maintaining the pluripotent characteristics of hESCs propagated in the transwell insert- based culture system. These combined results represent a significant development in properly segregating stem cells from their feeders, thus eliminating cell mixing, contamination, and providing the cells with a superior environment for nourishment and controlled self-renewal. Overall, this development in hESC propagation could have wide-reaching applications for self-renewal and differentiation studies within the field of stem cell biology.
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Perry, Shannon. "The Eastman Kodak Co. and the Canadian Kodak Co. Ltd : re-structuring the Canadian photographic industry, c.1885-1910." Thesis, De Montfort University, 2016. http://hdl.handle.net/2086/13060.
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Within the accepted historiography of photography, the importance of George Eastman and the Eastman Kodak Company (EKC) has become unassailable. They have been placed as the key, and often sole, agent in “revolutionizing” the amateur photography market in the late nineteenth century. While the photographic landscape and market of 1885-1914 was indeed radically altered, the historiographical dominance of what can be identified as the “Kodak story” has obscured the means through which EKC’s successful re-structuring of the existing manufacturing and distribution networks of photographic materials occurred. I argue that the changes effected by Eastman and the EKC began not with imaging desires, but with their acknowledgment, and profound understanding of the existing and competing interests within the photographic industry. This thesis focuses on the EKC’s re-structuring of the extant and evolving communities involved in the manufacturing and distribution of photographic materials in Canada between 1885-1910. Focusing particularly on the period immediately surrounding the establishment of the Canadian Kodak Co. Limited in 1899, I demonstrate the re-structuring processes at work, including: market and financial diversification; governmental lobbying; purchase and mergers; and other business and marketing-based strategies. I frame my theoretical positions and analysis of network re-structuring through the experiences of Ottawa professional photographer and photographic business owner William James Topley (active 1868-1907), and CKCoLtd manager John Garrison Palmer (active 1886-1921). Topley and Garrison’s professional experiences and interactions with expanded communities of photographic consumers and industry participants provide an opportunity for specific and detailed findings which challenge understandings of the evolution of the practice of photography during this transitional period. In doing so, I provide evidence of the primary role network re-structuring played in the EKC’s ability to shape the wider international photographic industry to their advantage in the early twentieth century.
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Carlisle, C. "Atomic-scale imaging of adsorption, oxidation and co-adsorption on Ag{111}." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597289.
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The work presented in this thesis draws upon several uses of STM, from structural determination, when used in conjunction with theoretical simulations, to the observation of surface reactions and surface mediated interactions. Simulations have been used here for the first time to allow the complete structural determination of a complex reconstruction. The determination of the reconstruction's structure and composition has enabled further experiments involving the oxidation of the Ag{111} surface as well as adsorbate-oxygen interactions mediated by the surface. The source of inspiration for these studies has been the catalytic epoxidation of ethene on silver by atomic oxygen. Two 'surface' states of atomic oxygen have been observed. The first, denoted Oc, is considered to adsorb in interstitial sites within the top layer of AG{111}. Its adsorbate-adsorbate repulsive nature sees this species rapidly saturating at a coverage of just 0.05 ML, at which point the p(4x4)-O species becomes more stable and its growth is nucleated at step edges. On decomposition of the p(4x4)-O reconstruction, both Ag{111} triangular islands and fractures within the oxide appear across the terraces. Both features may play a significant role in the catalytic behaviour. Ethene adsorption on clean Ag{111} has provided information on the adsorption geometry, adsorption state and appearance in the STM image allowing confident interpretations of the coadsorbed ethene-oxygen system. Tip pulsing has been used to provide a controlled mechanism for the induced transition from the physisorbed intrinsic precursor state of ethene to that of the chemisorbed state. High-resolution images have enabled the direct observation of Friedel surface oscillations surrounding the chemisorbed state. To my knowledge, this is the first direct observation of such oscillations resulting from adsorbates.
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Askar, Raid. "The role of tin in surface bonding of CO to Pt(111)." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-50842.
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We have used synchrotron radiation based photoelectron spectroscopy to study tin induced modifications in surface bonding of CO to Pt(111). Tin can form both so-called surface alloys, where tin replaces surface platinum atoms and ordered adatom structures where tin stays on top of the surface. The alloy is formed after annealing to 600 °C. The results from Pt(111) are in excellent agreement with previous literature, with CO binding in top site and in bridge site. On Pt(111)-Sn alloys we observe the same species, but with a reduced bridge site emission. Tin does not take direct part in the chemical bond to CO, but it influences the nearby Pt. On the overlayer structure we observe that CO binds directly to tin. Thus we conclude that the form of tin on the surface plays an important role in the surface chemistry of CO to tin modified Pt surfaces.
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Gimbert, Florian. "Structure électronique et propriétés magnétiques de nanostructures et superéseaux Co/Ni(111)." Toulouse 3, 2012. http://thesesups.ups-tlse.fr/1681/.
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Les matériaux à anisotropie magnétique perpendiculaire suscitent beaucoup d'intérêt, du fait de leur possible utilisation pour l'enregistrement magnétique de haute densité. Parmi les matériaux à anisotropie magnétique perpendiculaire, les multicouches Co/Ni sont particulièrement intéressantes car elles peuvent également être utilisées comme électrodes magnétiques dans des vannes de spin dont la configuration magnétique peut être modifiée grâce au couple magnétique (spin torque) exercé par un courant électrique polarisé en spin de relativement faible intensité. L'objectif de cette thèse est d'étudier la structure électronique de superéseaux Co/Ni(111) avec des codes de calcul DFT. Dans un premier temps, nous avons caractérisé les états électroniques localisés qui peuvent exister dans des nanostructures Co/Ni: états de Shockley à la surface de ces multicouches ou états de puits quantique dans une couche de Co déposée sur un substrat de Ni ou enterrée entre deux couches épaisses de Ni. Dans un second temps, nous avons cherché à comprendre l'origine de l'anisotropie magnétique dans les superéseaux Co/Ni(111) en reliant ses variations à la nature des états électroniques. Nous avons calculé l'énergie d'anisotropie magnétique des superéseaux Co/Ni(111) pour sélectionner ceux dont l'anisotropie magnétique est perpendiculaire. Nous avons relié l'anisotropie magnétique à l'anisotropie des moments magnétiques orbitaux des atomes du superéseau, en accord avec les conclusions du modèle de Bruno. La comparaison des moments magnétiques obtenus par calculs ab initio et mesurés par dichroïsme magnétique circulaire des rayons X (XMCD) a également été effectuéeMaterials with perpendicular magnetic anisotropy are interesting for high density magnetic recording. Among these materials, Co/Ni multilayers are promising because they can also be used as magnetic electrodes in spin valves, the magnetic configuration of which can be modified by spin torque effect using a low intensity spin polarised electric current. The aim of this thesis is to study the electronic structure of Co/Ni(111) multilayers from DFT calculations. We first described the localized electron states which can exist in these nanostructures: Shockley states at the surface of these multilayers or quantum-well states in Co layer grown on a Ni substrate or buried between two thick Ni layers. In a second step, we interpreted the magnetic anisotropy of Co/Ni(111) multilayers in terms of electron states. We calculated the magnetic anisotropy energy of Co/Ni(111) multilayers to select the systems with perpendicular magnetic anisotropy. We analyzed the magnetic anisotropy in terms of the anisotropy of the orbital magnetic moments of the atoms in the multilayers, according to the model developed by Patrick Bruno. The comparison between the magnetic moments calculated ab initio and measured by X-ray magnetic circular dichroism (XMCD) has also been performed
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CASTELLS, VICTORIA. "Etude theorique de l'interaction van der waals : de co dans le complexe co/ar a co adsorbee sur une surface de n(=1,2)ar/pt(111)." Paris 11, 1996. http://www.theses.fr/1996PA112053.
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Une etude theorique (structure et dynamique) des forces de van der waals est presentee dans le cadre du systeme ar#. #. #. Co soit isole, soit adsorbe sur un substrat metallique de pt(111) sur lequel ont ete depose des couches successives d'argon jouant le role d'espaceurs. Dans la limite de la molecule isolee, un calcul de dynamique quantique permet d'acceder aux raies (positions et intensites) du spectre infrarouge. La comparaison avec l'experience permet d'une part de tester le potentiel ab initio recemment calcule par shin et al. (en particulier du point de vue de sa sensibilite vis-a-vis de l'anisotropie) et d'autre part de discuter du caractere libre ou rigide du rotateur. Ar#. #. #. Co se comporte approximativement comme un rotateur symetrique, en forme de t, et son caractere non-rigide apparait dans le fait que certaines constantes rotationnelles dependent du moment angulaire. Des raies non encore attribuees du spectre experimental sont interpretees en termes d'excitation du mode de pliage. Dans le cas de co adsorbe sur pt(111) avec n couches d'espaceurs ar, le potentiel est calcule par une somme d'interactions atome-atome. La convergence est testee par rapport aux differentes couches de pt introduits en profondeur et au nombre d'atomes de surface pour un site d'adsorption donne. La variation avec n de trois observables est analysee: la force de la liaison, l'angle d'inclinaison et la distance adsorbat-surface, caracteristiques du passage de la chimisorption vers la physisorption. Une transition relativement brutale est obtenue avec une seule couche d'argon et l'augmentation de n a pour effet de faire varier dans la limite d'un facteur 2 a 3 les forces de liaison dans le regime de la physisorption
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Wagner, Jean-Bernard. "Jean-Baptiste Paul Louis Chibret (1844-1911), co-fondateur de la Société française d'ophtalmologie." Strasbourg 1, 1985. http://www.theses.fr/1985STR1M042.
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Meier, Focko Karl. "Co on Pt(111) studied by spin-polarized scanning tunneling microscopy and spectroscopy." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982018266.
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Yim, Chi Ming. "LEEM investigations of adsorption and diffusion of CO on the Pt(111) surface /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202007%20YIM.
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Mehlhorn, Michael. "Dynamik von CO und D2O auf Cu(111) laserinduzierte und thermisch induzierte Prozesse /." [S.l.] : [s.n.], 2005. http://www.diss.fu-berlin.de/2006/492/index.html.
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Everitt, Jean. "Co-operative society libraries and newsrooms of Lancashire and Yorkshire from 1844-1918." Thesis, Aberystwyth University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268198.
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Daykin, Adam C. "A TEM analysis of the Co//Si(111) system using bicrystallographic symmetry theory." Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316591.
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Bose, Aniruddha. "The Port of Calcutta (1860-1910): State Power, Technology and Labor." Thesis, Boston College, 2013. http://hdl.handle.net/2345/3749.
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Thesis advisor: Prasannan ParthasarathiThis dissertation is a study of state power, technological change, and class conflict at the port of colonial Calcutta. It explores the period between 1860 and 1910 in order to recast historical understandings of the relationship between the colonial state, science and technology, and labor. The dissertation explores a period of great change, resulting from massive increases in public investment. These investments transformed the port's infrastructure, making the loading and unloading of cargo ships significantly easier. They were also designed to secure the supply of cheap labor, and better supervise the port's labor force. The investments involved the deployment of new technologies and scientific knowledge. This included various new kinds of machinery, such as cranes and railroads that were designed to speed up the pace of work or occasionally to automate the loading and unloading of cargoes, as well as, the use of new medical knowledge to prevent the spread of disease. International trade benefited greatly from these investments, but their effects on labor were more complex. The new machinery made the work of loading and unloading easier, but also more dangerous. Moreover, many workers resented the enhanced supervision that they were subject to. In a bid to secure the supply of labor, the government authorities managing the port attempted to alter the existing casual hiring practices of the port with new hiring systems wherein laborers were locked into long term contracts with their employers. Many workers fought back through acts of everyday resistance and well organized strikes. They were most successful towards the turn of the century when a plague epidemic disrupted the supply of labor in Calcutta. While some workers fled the city, others fought for, and won higher wages. The state was also forced to invest in expensive automation and labor welfare projects in order to secure their workforce. The dissertation highlights the critical role of technology in the reshaping of labor relations in the British Raj. It also underscores the central importance of trade for the colonial state. Finally, the dissertation underscores the dialectic that characterized the relationship between labor and colonial capital
Thesis (PhD) — Boston College, 2013
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: History
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Silva, Alysson Martins Almeida. "Crescimento e estrutura de monocamadas de Co sobre Cu90Au10(100)." CNEN - Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, 2008. http://www.bdtd.cdtn.br//tde_busca/arquivo.php?codArquivo=101.
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NenhumaO estudo das correlações entre as propriedades estruturais e magnéticas de filmes finos e ultrafinos é hoje assunto de grande interesse tanto científico como tecnológico, sendo que, dada a disponibilidade de materiais e a importância das aplicações atuais e potenciais, filmes magnéticos compostos por metais e ligas de metais de transição 3d estão entre os materiais mais investigados. O Co é um metal de transição 3d, ferromagnético, e que, em volume, apresenta estrutura hexagonal compacta (hc). Entretanto, tanto esta fase como as fases cúbica de face centrada (cfc) e cúbica de corpo centrado (ccc) podem ser estabilizadas à temperatura ambiente na forma de filmes ultrafinos, ou ainda em forma de estruturas multicamadas, e as propriedades magnéticas dos mesmos apresentam uma complexa correlação com a estrutura cristalina. Existe um grande numero de trabalhos a respeito de Co crescido sobre superfícies de Cu (cfc, parâmetro de rede a = 3,615 Å) e outros monocristais, mas nada há na literatura sobre monocamadas de Co depositadas sobre Cu90Au10, uma liga cfc com parâmetro de rede (3,66 Å) expandido de 1,0% em relação ao Cu. Investigamos aqui o crescimento, em condições de epitaxia de feixe molecular (MBE), e a estrutura de filmes de Co depositados a temperatura ambiente, com espessuras entre uma e cinco monocamadas atômicas (ML) depositadas sobre a superfície (100) da liga Cu90Au10. A composição química e a pureza da superfície do monocristal e dos filmes foram determinadas por espectroscopia de elétrons excitados por raios X (XPS). A cristalinidade da superfície do substrato, bem como a forma de crescimento e a estrutura dos filmes foram determinados por difração de elétrons de baixa e alta energia, LEED e RHEED. A morfologia da superfície do cristal de Cu90Au10(100) e das primeiras monocamadas do filme de cobalto foram determinadas através de medidas de microscopia de varredura por tunelamento (STM). Medidas de magnetometria por efeito Kerr magneto- óptico foram utilizadas para se estabelecer, em caráter preliminar, uma correlação entre a estrutura e o magnetismo dos filmes de Co sobre Cu90Au10(100) Nossos resultados indicam o crescimento de Co com estrutura tetragonal de face centrada (tfc), e uma evolução, com o aumento da espessura de cobalto, de formação de ilhas para crescimento camada a camada. Além disso, nota-se para os filmes de Co uma rápida contração do parâmetro de rede no plano, atingindo aproximadamente 2,5% para ~ 4,0 ML, quando comparado ao substrato de Cu90Au10 (100). Medidas de magnetometria por Efeito Kerr Magneto-ótico indicam magnetização no plano do filme. Este trabalho eminentemente experimental representou um amplo aprendizado no uso e exploração das potencialidades de técnicas múltiplas (LEED, RHEED, XPS, AES, STM e MOKE) para a adequada caracterização e investigação das propriedades estruturais e magnéticas de superfícies e nanoestruturas heteroepitaxiais preparadas em UHV, em condições de epitaxia de feixe molecular (MBE), bem como o primeiro estudo do crescimento de monocamadas de Co depositadas sobre Cu90Au10(100).
The investigation of correlations between structural and magnetic properties of thin and ultrathin films is of great scientific and technological interest presently. Due to importance of their actual and potential applications, films of 3d metals and their alloys are among the most investigated materials. Co is a ferromagnetic 3d metal that in bulk has a hexagonal compact structure (hcp). For Co films or multilayers, the hcp as well as the face-centered (fcc) and bodycentered cubic (bcc) phases can be stabilized at room temperature, depending on the used substrate. It is known that the preparation method can affect decisively the structural and magnetic properties of Co monolayers. There is a big amount of work on Co films grown on different Cu surfaces (fcc; lattice parameter a = 3.615 Å) and other substrates but, to the best of our knowledgement, there is no studies on Co monolayers deposited on Cu90Au10(100), a fcc alloy with lattice parameter of about 3.66 Å. In this work we investigate the epitaxial grow and the structure of Co films with thickness up to 5 atomic monolayers (ML) deposited on Cu90Au10(100). The goal of the study was to investigate the modifications in the magnetic properties of the Co films provided by small distortions in the lattice, since Cu90Au10 presents cfc structure with a lattice parameter ~1% larger than the one of the pure Cu. The sample preparation and the majority of the experimental analysis has been done in ultra high vacuum under molecular beam epitaxy conditions. The studies were conducted in situ, in UHV, by using x-ray photoelectron spectroscopy (XPS), high and low energy electron diffraction (RHEED and LEED), and scanning tunneling microscopy (STM). Preliminary magnetic measurements on the correlation structure - magnetism were conducted by magneto-optical Kerr effect (MOKE). Our results indicate the growth of a tetragonal distorted face centered (fct) Co lattice and an initial formation of islands followed by a layer-by-layer grow starting from 2 ML Co. The lateral lattice parameter shows a fast contraction with increasing thickness when compared to the CuAu substrate, reaching ~ 2.5% at 4 ML Co. Surface magnetometry by Magneto-optical Kerr effect indicated in-plane magnetization of the Co films. This experimental work represented a broad and extensive learning process on preparation and characterization of heteroepitaxial nanostructures by multiple techniques (LEED, RHEED, XPS, AES, STM, and MOKE) under MBE conditions (UHV) and the first investigation of Co monolayers on Cu90Au10(100). SUMÁRIO
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Dupuis, Anne-Claire. "V 2 O 3 (0001)/Au(111) and /W(110)." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2002. http://dx.doi.org/10.18452/14834.
Full textAbstract:
Ziel dieser Arbeit war es, die Reaktivität von V2O3(0001) zu untersuchen. In dieser Arbeit wird sich zunächst mit dem epitaktischen Wachstum von V2O3-Filmen auf Au(111)und W(110) befaßt. Stöchiometrie und Geometrie der dünnen Filme wurden mit Röntgenphotoelektronenspektroscopie (XPS), Röntgenabsorptionsspektroskopie (NEXAFS) und Beugung niederenergetischer Elektronen (LEED) charakterisiert. Wir haben gezeigt, dass die Oberfläche zwei Terminierungen aufweist, die sich durch die An- bzw. Abwesenheit von zusätzlichen Sauerstoffatomen auf der Oberfläche unterscheiden. Diese Sauerstoffatome bilden Vanadylgruppen mit den Oberflächenvanadiumatomen, deren Streckschwingung mit Infrarotabsorptionsspektroskopie (IRAS) detektiert werden kann. Die elektronische Struktur des V2O3(0001) dünnen Filmes wurde mittels UV-Photoelektronenspektroskopie (UPS), XPS und NEXAFS untersucht. Wir haben bewiesen, dass die Bildung von Vanadylgruppen an der Oberfläche einen Metall-Isolator Übergang hervorruft. Für jede Oberflächenterminierung wurde ein elektronenenergieverlustspektrum (HREELS) gezeigt und mit einem Spektrum des isomorphischen Cr2O3 verglichen. Wasseradsorptionsexperimente zeigen, dass Wasser sowohl molekular als auch dissoziativ auf beiden Oberflächen adsorbiert. Die Dissoziationswahrscheinlichkeit hängt von der Terminierung und von der Bedeckung ab. Sie ist am höchsten bei großer Bedeckung auf der -V=O Oberfläche. CO2 Adsorption wurde mit UPS, XPS, HREELS und IRAS untersucht. CO2 physisorbiert auf der -V=O Oberfläche. Den IRA Spektren entnehmen wir, dass CO2 auf der -V Oberfläche als gewinkelte Spezies adsorbiert. Heizen dieser Spezies auf 200 K führt zu Karbonatbildung. Die Adsorption von CO verhält sich ähnlich wie die von CO2: nur kleine Menge adsorbieren auf der -V=O Oberfläche, während die -V Oberfläche viel reaktiver zu sein scheint. Winkelaufgelöste UPS Messungen deuten auf eine flache CO Adsorptionsgeometrie auf der -V=O Oberfläche hin. NEXAF- und IRA-Spektren zeigen dagegen, dass bereits bei 90 K sich CO2 auf der -V Oberfläche bildet.In this work, we firstly showed that it is possible to grow thin V2O3(0001) films on Au(111) and W(110). The stoichiometry of the film has been characterized by X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure spectroscopy (NEXAFS). We inferred with infrared absorption spectroscopy (IRAS) the existence of two possible terminations of the V2O3(0001) surface. These two terminations differ only by the presence or not of oxygen atoms on the top of the surface, forming vanadyl groups with the surface vanadium atoms. We studied with UV photoelectron spectroscopies (UPS), XPS and NEXAFS the electronic structure of our V2O3(0001) thin films. Our data evidence a metal to insulator transition induced by the formation of the vanadyl groups on the surface. We performed high resolution electron energy loss spectroscopy (HREELS) measurements and presented a phonon spectrum for each termination. We compared our spectra with a spectrum of the isomorphic Cr2O3(0001). We studied the water adsorption properties of both surface terminations. We observed molecularly adsorbed water on both surface terminations for low exposures. For large exposures, water dissociates and OH-groups were detected. We performed CO2 adsorption experiments with UPS, XPS, HREELS and IRAS. The analyze of the IRAS results on the -V terminated surface leads us to the conclusion that CO2 adsorbs in a bent configuration. With UPS and XPS, we could evidence the formation of carbonates upon heating up to 200 K. On the -V=O surface, CO adsorbs molecularly and we concluded from the angle resolved UPS data that the CO molecule is strongly tilted on the surface. With NEXAFS and IRAS, we showed the formation of CO2 on the -V surface.
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McEachern, Cameron James. "The Co-operative Commonwealth Federation and small business /." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63990.
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Narain, Namrata. "Co-option and control : the role of the colonial army in India, 1918-1947." Thesis, University of Cambridge, 1992. https://www.repository.cam.ac.uk/handle/1810/272251.
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Matsutsu, Molefi. "DFT insight into the oxygen reduction reaction (ORR) on the Pt₃Co(111) surface." Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/22066.
Full textAbstract:
Proton exchange membrane fuel cells (PEMFC) are identified as future energy conversion devices, for application in portable and transportation devices. The preferred catalyst for the PEMFC is a Pt-catalyst. However, due to the slow oxygen reduction reaction (ORR) kinetics, high Pt loadings have to be used. The high Pt loadings lead to high costs of the PEMFC. Pt-Co alloys have been identified as catalysts having higher ORR activity higher than of a Pt-catalyst. Therefore, in the present study, the Density Functional Theory (DFT) technique is used to gain fundamental insight into the ORR on the Pt₃Co(111) surface. The calculations have been performed using the plane wave based code, the Vienna ab-initio Simulation Package (VASP). DFT spin-polarized calculations, utilizing the GGA-PW91 functional, have been used to study the adsorption of the ORR intermediates, viz. O₂, O, OOH, OH, H₂O and HOOH on the Pt₃Co(111) surface. The results obtained on the Pt₃Co(111) surface are compared to the results obtained on the Pt(111) surface. The adsorption strength of the ORR intermediates has been shown to be affected by the presence of Co to varying extents on the Pt₃Co(111) surface relative to adsorption on the Pt(111) surface. The most strongly stabilised ORR intermediate on the Pt₃Co(111) surface relative to adsorption on the Pt(111) surface is O: on the Pt₃Co(111) surface O is 0.45 eV more strongly adsorbed than on the Pt(111) surface. The least affected ORR intermediate is H₂O: H₂O adsorption on the Pt₃Co(111) surface is 0.20 eV more stable than on the Pt(111) surface. The energetically favorable, i.e. most strongly bound adsorption configurations for all the ORR intermediates involves a configuration in which the ORR intermediate is bonded to a surface Co atom. Therefore, the surface Co atom stabilizes the adsorption of the ORR intermediates, relative to adsorption on the Pt(111) surface. Coadsorbed configurations have been used to study the formation and dissociation of the ORR intermediates. From the coadsorption studies, it is shown that there is an energy cost associated with moving the adsorbates from their lowest energy sites, while separately adsorbed, to the higher energy coadsorbed state, prior to reaction. Hence, adsorbate-adsorbate interactions are expected to destabilize the coadsorbed state at the coverages considered in the present study. The Climbing Image Nudged Elastic Band (CI-NEB) method has been used to locate the transition states and to calculate the activation energies of the different elementary reaction steps. The calculated dissociation reaction activation energies for the Pt₃Co(111) surface are found to be lower than the dissociation activation energies calculated on the Pt(111) surface. The most lowered dissociation activation energy is for the dissociation of O₂: on the Pt₃Co(111) surface the activation energy is 0.08 eV, whilst on the Pt(111) surface the activation energy is 0.59 eV. For the hydrogenation reaction steps, only the hydrogenation of O to form OH occurs with a lower activation energy of 0.86 eV on the Pt₃Co(111) surface, compared to 0.95 eV on the Pt(111) surface. For other hydrogenation reaction steps, the activation energies on the Pt₃Co(111) surface are higher than those on the Pt(111) surface. Based on the calculated activation energies of the elementary ORR reaction steps, the dissociative and the O-assisted H₂O dissociation mechanisms are identified as the mechanisms most likely to be dominant on the Pt₃Co(111) surface, due to having lower activation energies relative to the associative mechanisms. For both mechanisms, the reaction step with the highest activation energy is the step involving O, i.e. O hydrogenation to form OH for the dissociative mechanism, and the O* + H₂O* --> 2OH* reaction for the O-assisted H₂O dissociation mechanism. Thus, the reaction step involving the reaction of the strongly adsorbed O species, is identified as the potential rate limiting step of the ORR. Both the dissociative and the O-assisted H₂O dissociation mechanisms are expected to be in competition on the Pt₃Co(111) surface, since the potential rate limiting step for both mechanisms have similar activation energies. Hence, the preferred mechanism will depend on the relative abundances of the H species and H₂O on the Pt₃Co(111) surface. A microkinetic analysis would be need needed to fully account for concentration and entropic contributions to the rate of reaction for the different ORR elementary reaction steps.
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BOUKARI, SAMY. "Etude des proprietes structurales et magnetiques de films minces de cr/co/pd(111)." Université Louis Pasteur (Strasbourg) (1971-2008), 1998. http://www.theses.fr/1998STR13196.
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Cette these est consacree a l'etude de la croissance, de la structure et des proprietes magnetiques de l'interface cr/co, le cobalt etant epitaxie sur un monocristal de pd(111). L'etude de la croissance et de la structure a ete conduite sous ultravide par diffractions d'electrons lents, diffraction de rayons x en incidence rasante et spectroscopie auger. Les mesures magnetiques ont ete realisees par effet kerr magneto-optique in situ. Concernant les depots de co/pd(111), j'ai montre que la croissance a 293 k du co se fait par ilots bicouches jusqu'a une monocouche deposee, puis en multicouches simultanees. La structure est majoritairement cfc maclee. Les films ont ete recuits jusqu'a 470 k ce qui provoque le lissage de la surface, fait apparaitre la phase hcp du co, et entraine une faible interdiffusion. Le depot de co a 370 k stabilise la phase hcp sans interdiffusion et sans segregation de pd. Quelles que soient les conditions de preparation considerees, il est possible de moduler l'etat de contrainte du film en changeant son epaisseur. La croissance du cr sur les films epitaxies de co/pd(111) procede par ilots sans interdiffusion. Les relations d'epitaxie entre le cr et le co dependent de l'etat de contrainte du co : le cr adopte l'orientation kurdjumov-sachs sur les films de co les plus contraints, et l'orientation nishiyama-wassermann sur les films plus epais, moins contraints. La couverture de cr provoque une transition du co cfc en co hcp. La description structurale detaillee permet de correler qualitativement les proprietes magnetiques a l'etat des contraintes, a la structure, a la segregation de pd et a l'interdiffusion. L'analyse quantitative de l'anisotropie magnetique d'un film de co depose a 370 k et recouvert de cr montre l'importance primordiale des effets magneto-elastiques dans ce systeme, et suggere une anisotropie magnetocristalline d'interface negative entre le cr et le co.
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Aguirre, John. "Study of 3-Dimensional Co-Flow Jet Airplane and High-Rise Building Flow Using CFD Simulation." Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_theses/181.
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The purpose of this thesis is to design and study an aircraft which implements the Co-Flow Jet (CFJ) airfoil concept, as well as to study the CAARC standard highrise building. The design concept is verified mainly by the use of a Computational Fluid Dynamics (CFD) package. A thorough methodology for geometry and mesh generation is developed, and subsequently applied to the two cases. The first case studied is that of the CFJ Airplane (CFJA). It consists of a threedimensional, highly blended, ying wing geometry implementing the Co-Flow Jet airfoil concept. Though a thorough comparison to a baseline geometry, it is shown that usage of the CFJ airfoil cross-section greatly improves aircraft performance by increasing lift, reducing drag, and providing a source of thrust over the operational range of angles of attack. A steady state CFD simulation is used for this case, as the air ow around an airfoil cross-section is inherently steady for attached ows. CFD results are used to support the Engineless Aircraft" concept, where the CFJ airfoil is used as the sole form of propulsion. The second case studied consists of a rectangular high-rise building undergoing a wind condition with Mach number of 0:1 and a Reynolds number of 160000. Due to the non-streamlined geometry of the building cross-section, aerodynamic instabilities due to uid separation are present, and therefore an unsteady CFD analysis is necessary to fully resolve all of the ow phenomena. Preliminary steady state results are presented, and a plan is laid down for the future study of this highly complex case. Results are presented for a variety of angles of attack in the case of the CFJA, and for the main ow direction in the case of the CAARC building. Results are compared with baseline geometry in the case of the CFJ Airplane. The CFJ Airplane case is simulated using a 3rd order steady state scheme, which is sufficient to achieve valid results for the ow regime. The CAARC building, which has inherent ow separation, requires the use of high order schemes.
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Baricuatro, Jack Hess L. "Electrodeposition of ultrathin Pd, Co and Bi films on well-defined noble-metal electrodes: studies by ultrahigh vacuum-electrochemistry (UHV-EC)." Texas A&M University, 2006. http://hdl.handle.net/1969.1/4291.
Full textAbstract:
Three illustrative cases involving the electrodeposition of ultrathin metal
films of varying reactivities onto noble-metal substrates were investigated: (i) Pd
on Pt(111), a noble admetal on a noble-metal surface; (ii) Bi on Pd(111), a less
noble admetal on a noble-metal surface; and (iii) Co on polycrystalline Pd and
Pd(111), a reactive metal on a noble-metal surface. The interfacial
electrochemistry of these prototypical systems was characterized using a
combination of electrochemical methods (voltammetry and coulometry) and
ultrahigh vacuum electron spectroscopies (Auger electron spectroscopy, AES;
low energy electron diffraction, LEED; and X-ray photoelectron spectroscopy,
XPS).
Potential-controlled adsorption-desorption cycles of aqueous bromide
exerted surface smoothening effects on ultrathin Pd films with defect sites
(steps). This procedure, dubbed as electrochemical (EC) annealing, constituted a
nonthermal analogue to conventional annealing. EC-annealed ultrathin Pd films
exhibited long-range surface order and remained free of oxygen adspecies. Pdadatoms occupying step-sites were selectively dissolved and/or rearranged to
assume equilibrium positions in a well-ordered (1x1) film.
Electrodeposition of Co was found to be highly surface-structuresensitive.
While virtually no Co electrodeposition transpired on a clean Pd(111)
surface, Co was voltammetrically deposited on (i) a Pd(111) electrode
roughened by oxidation-reduction cycles; and (ii) thermally annealed
polycrystalline Pd, which is a composite of the (111) and (100) facets.
Electrodeposition of Co was also observed to be kinetically hindered and slow
potential scan rates (0.1 mV/s) were required.
Well-defined ultrathin Bi films were potentiostatically electrodeposited
onto Pd(111); a Stranski-Krastanov growth mode was indicated. The
electrochemical reactivity of ultrathin Bi films was characterized using two
surface probes: aqueous iodide and D-glucose. (i) Exposure of the prepared Bi
adlayers (ÃÂBi 0.33) to aqueous iodide gave rise to (âÂÂ3xâÂÂ7) I-on-Bi superlattice.
The same superlattice was obtained if Bi was electrodeposited onto
Pd(111)(âÂÂ3xâÂÂ3)R30o-I. (ii) With respect to electrooxidation of D-glucose on
Pd(111), the presence of Bi adlayers inhibited the by-product-induced "surface
poisoning" of Pd(111) but reduced its electrocatalytic efficiency.
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Tsurkan, Sergey [Verfasser]. "Magnons in ultrathin Fe/Co multi-layers on W(110) and Ir(111) / Sergey Tsurkan." Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1227451245/34.
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Scholes, Fiona Helen. "Far-infrared emission spectroscopy of C₆D₆ and CO on pt(111) and pt(110)." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621412.
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Southern, Jayne Brenda. "The Co-operative movement in the north west of England, 1919-1939 : images and realities." Thesis, Lancaster University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337458.
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Nakata, Dorene Samantha. "Syn-eruptive degassing of a single submarine lava flow : constraints on MORB CO₂ variability, vesiculation, and eruption dynamics." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1912/3933.
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Thesis (S.M.)--Joint Program in Marine Geology and Geophysics (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 33-37).
Mid-ocean ridge basalts (MORBs) exhibit a wide range of CO2 concentrations, reflecting saturation to supersaturation (and rarely undersaturation) relative to their emplacement depths. In this study, we explore the mechanisms of CO2 degassing and the implications this has for estimating the advance rates and durations of seafloor eruptions. We present dissolved volatile concentrations (mainly of CO 2 and H20) and vesicle size distributions (VSDs) for a unique suite of MORB glasses collected at the East Pacific Rise, ~9° 50' N. These MORB glasses were collected at -200 m intervals along an across-axis track over a single flow pathway within the recently emplaced 2005-06 eruption boundaries; systematic sample collection provides one of the first opportunities to characterize intra-flow geochemical and physical evolution during a single eruption at a fast-spreading ridge. Compared to measurements of MORB volatiles globally, dissolved H20 concentrations are relatively uniform (0.10 - 0.16 weight percent), whereas dissolved CO2 contents exhibit a range of concentrations (154 - 278 ppm) and decrease with distance from the EPR axis (i.e., eruptive vent). Ion microprobe analysis of dissolved volatiles within the MORB glasses suggest that the magma erupted supersaturated (pressure equilibrium with 920 - 1224 mbsf) and in near-equilibrium with the melt lens of the axial magma chamber (~1250 - 1500 mbsf), and degassed to near equilibrium (299 - 447 mbsf) with seafloor depths over the length of the flow. The decrease in CO 2 concentrations spans nearly the full range of dissolved CO2 contents observed at the EPR and shows that the varying degrees of volatile saturation that have been observed in other MORB sample suites may be explained by degassing during emplacement. Vesicularity (0.1 - 1.2%) increases with decreasing dissolved CO2 concentrations. We use vesicle size distributions (VSDs)-vesicle sizes and number densities-to quantify the physical evolution of the CO2 degassing process. VSDs suggest that diffusion of CO2 into preexisting vesicles, and not nucleation of new vesicles, is the dominant mechanism of increasing CO2 in the vapor phase. We also use VSDs, along with estimates of vesicle growth rates, to constrain emplacement time of the 2005-06 eruption to <~24 hours and to resolve variations in advance rate with down flow distance.
by Dorene Samantha Nakata.
S.M.
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Werier, Leah. "From Vitrine to Screen: Art and the Architecture of Commodity Display." Thesis, 2021. https://doi.org/10.7916/d8-jgd0-7f97.
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This dissertation is a study of the architecture of commodity capital: the display window. Taking as a starting point the work of Henri Lefebvre and Goerg Simmel, this dissertation understands the shop window to be a mode of display, what I define as “the logic of the vitrine,” that has shaped the way the world appears. Tracing a genealogy from the Parisian Arcades to the twentieth-century department store, this project explores the relationships between gender, sexuality, race, and architecture. Feminist critiques of commodity desire and display illuminate how the shop window is as important to our understandings of capitalism as is the commodity.
Through feminist, queer, postcolonial, and anti-racist readings of material and commodity culture, this dissertation considers the shop window to be a site of subject formation. This dissertation also examines how designers, artists, and architects have explored the display of the shop window through a series of case studies, including Marina Abramovic’s Role Exchange, Gene Moore’s “drag” in Bonwit Teller’s shop windows, the making of a black mannequin, and Lynn Hershman Leeson’s site-specific installation 25 Windows. This dissertation concludes with a consideration of the architectural role reversals of the shop window and the gallery; the work of Silvia Kolbowski and Elmgreen and Dragset’s Prada Marfa ground this analysis. Artists have disrupted the display of the shop window, transforming the architecture of commodity capital into a space for resistance and critique.
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"Farmer's Expectations and the Saskatchewan Co-Operative Elevator Co. 1908-1917." Thesis, 1988. http://hdl.handle.net/10388/5753.
Full textAbstract:
On March 14, 1911, following the recommendations of the
Saskatchewan Royal Commission on Grain Elevators, the Sask
atchewan government of Walter Scott created the Saskatchewan
Co-operative Elevator Company (SCECo). It marked the
cUlmination of a decade of farmer attempts to reform the
grain trade. Supported by the Saskatchewan Grain Growers'
Association (SGGA), the Co-op, as the elevator company came
to be known, experienced tremendous growth. Membership
expanded from 2,508 in 46 locals to 13,156 in 192 locals
during the first three years of operation. By 1917 the
SCECo operated 258 country elevators, a marketing company
with a seat on the Winnipeg Grain Exchange, and a terminal
elevator at Port Arthur. Still, the Co-op was not a
complete success.
The farm movement had looked upon elevator reform as a
panacea for handling, marketing, transportation and credit
problems. Under the terms of its charter, however, the
SCECo operated within the existing marketing system buying
and selling grain to supplement its unprofitable storage and
handling business. Moreover, the Company's commercially
minded and centralised management refused to implement
several non-marketing reforms desired by the farm movement.
Despite the Co-opts great success in the elevator business,
it failed to meet the high expectations of farmers.
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Ho, Huei-Ying, and 何慧瑩. "Comparative studies in structural and magnetic properties between Ni/Co/Pt(111) and Co/Ni/Pt(111)." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/39740542022621830062.
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博士國立臺灣師範大學
物理學系
94
The comparative studies in structural and magnetic properties between Ni/Co/Pt(111) and Co/Ni/Pt(111) were investigated by Auger electron spectroscopy (AES), low-energy electron diffraction (LEED), ultra-violet photoemission spectroscopy (UPS), and magneto-optical Kerr effect (MOKE). The oscillation of the specular beam of LEED and the Auger uptake curve were used to calibrate the thicknesses of Ni films and Co films, especially to study the growth modes at room temperature. The growth modes at room temperature of both dNi Ni/1 ML Co/Pt(111) and dCo Co/ 1 ML Ni/Pt(111) (d: thickness) are at least 2 ML in layer-by-layer growth before the 3-dimensional island growth begins. For the both systems, the Co and Ni atoms intermix to each other at low temperature annealing, after which the Co and Ni atoms diffuse into the Pt substrate together. The starting temperatures of the intermixing process for 1-3 ML Ni/1 ML Co/Pt(111) are independent on the thickness of Ni overlayer. But for the dCo Co/ 1 ML Ni/Pt(111) system, the starting temperatures of the intermixing process is thickness dependent. The starting temperatures of the Ni-Co intermixing layer diffusing into the Pt substrate for both dNi Ni/1 ML Co/Pt(111) and dCo Co/ 1 ML Ni/Pt(111) increase with the thickness of the overlayers. The polar and longitudinal hysteresis loops were detected during the initial growths. The easy axis of the magnetization of 1-24 ML Ni/1 ML Co/Pt(111) is in the out-of-plane direction. But for the dCo Co/ 1 ML Ni/Pt(111) system, no Kerr signal is observed at room temperature when the thickness of Co film is below 3 ML. The disappearance of the polar Kerr rotation for dCo < 3 ML in Co/1 ML Ni/Pt(111) system at room temperature may due to the Ni buffer layer preventing the Co atoms in contact with Pt substrate. The evolution of the magnetization versus annealing temperature for dCo Co/ 1 ML Ni/Pt(111) was consistent with diffusion process to form Ni-Co-Pt surface alloy after annealing at high temperatures. The coercivity of the Ni-Co-Pt system can be adjusted by changing the annealing temperature, due to the variety in concentrations of the alloy formation. The comparative study in structural properties for the mirror systems, 1 ML Ni/1 ML Co/Pt(111) and 1 ML Co/1 ML Ni/Pt(111), reveal an information of a structural phase transition from NixCo1-xPt to NixCo1-xPt3 when the annealing temperature is between 750 K and 780 K, while the value of critical exponent near the Curie point exists a crossover from a 2D-like magnetic phase to a 3D-like one. The Curie temperature depresses rapidly when the subsurface structure changes from NixCo1-xPt to NixCo1-xPt3. The Curie temperature of 1 ML Ni/1 ML Co/Pt(111) are always higher than that of 1 ML Co/1 ML Ni/Pt(111). We found that this phenomenon is corresponding to the ratio of Ni% to Co% in the subsurface region. The influence of the concentration ratio in Curie temperature is also confirmed by the studies of 2 ML Ni/1 ML Co/Pt(111), 2 ML Co/1 ML Ni/Pt(111), 12 ML Ni/1 ML Co/Pt(111), and 24 ML Ni/1 ML Co/Pt(111). Another mirror systems, 2 ML Ni/2 ML Co/Pt(111) and 2 ML Co/2 ML Ni/Pt(111), were performed to compare with the mirror system, 1 ML Ni/1 ML Co/Pt(111) and 1 M L Co/1 ML Ni/Pt(111). A spin reorientation transition (SRT) occurred after high-temperature annealing. It is interesting that no SRT was observed in the systems with one-ML buffer layer. The temperature dependence of the ratio of Ni% to Co% for 2 ML Ni/2 ML Co/Pt(111) and 2 ML Co/2 ML Ni/Pt(111) causes the SRT is discussed.
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Bakalarz, Dominik. "Molecular mechanisms of novel carbon monoxide and hydrogen sulfide donors activity enhancing physiological gastric mucosal integrity against acute drug-induced gastrotoxicity." Praca doktorska, 2021. https://ruj.uj.edu.pl/xmlui/handle/item/288598.
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陳俊明. "Magnetic properties of Co/CoO/Ir(111) grown on Ir(111)." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/60182782145674187312.
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許志榮. "Exchange-bias phase diagram of CoO/Co/Si(111) and magnetic properties of Co/Ag-Si √3×√3/Si(111)." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/14394464097149320427.
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碩士國立臺灣師範大學
物理學系
99
In this thesis, we focus on the physical properties of CoO/Co/Si(111) and Co/Ag-Si √3 × √3/Si(111) systems. For CoO/Co/Si(111) with CoO thickness between 5 and 15 monolayers (ML), a phase diagram of the exchange bias has been established by way of comparing the results of zero-field cooling and field cooling. For CoO thinner than 10 ML, enhanced coercivity is observed because of the existence of nano-sized CoO particles at the interface. For CoO thicker than 15 ML, non-zero exchange field is observed because the magnetic anisotropy is large enough. For a Co/Ag-Si √3 × √3/Si(111) system, Co overlayer has been deposited on the top of Ag-Si √3 × √3/Si(111) surface alloy. For Co thinner than 4.38 ML, no Kerr signal is detected in the longitudinal configuration. The easy axis of magnetization for Co/Ag-Si √3 × √3/Si(111) is in the surface plane. By extrapolating the data for Kerr signal versus the Co thickness, the zero intercept shows no magnetic dead layer. This shows that the Ag-Si √3 × √3/Si(111) surface alloy is efficient for preventing the silicide formation between the Co layer and the silicon substrate. From the cryogenic treatments of the specimens, the Curie temperature of 3.65 ML Co/Ag-Si √3 × √3/Si(111) is between 275 and 300 K. while that of 3.51 ML Co/Ag-Si √3 × √3/Si(111) is below 150 K. In addition, my designs and efforts on the movement and reestablishment of the ultrahigh vacuum system have been discussed.
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Jerry, Jen, and 曾惓慈. "Geometrical structure study of Co on Cu(111)." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/57790562408044336959.
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郭長祐. "The change of behavior with temperature of Co on Si(111)-7×7 and Co on(√3×√3)Ag/Si(111)surface." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/31833196287666975906.
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碩士國立臺灣師範大學
物理學系
94
Cobalt atoms can react with the adatoms of Si（111）-7×7 surfaces at the room temperature. The reaction transfers the electric state of Si adatoms. The bright dots change to dark dots under the scanning tunneling microscopy（STM） observation of negative bias. By the statistic method, we find the most of dark dots appear at unfaulted half unit cell（UHUC）center sites. The behavior of Co/Si（111）-7×7 system are observed at low temperatures by using a variable temperature STM. At 100K, we find that Co atoms will not react with silicon but randomly adsorb on the surfaces. As the temperature increasing, the critical temperature of the reaction among 126K and 130K are found by STM observations. We suppose that the Co atoms will diffuse and react with Si（111）-7×7 UHUC center site at higher temperatures. Co atoms which are deposited on the（ × ）-Ag/Si（111）surfaces are simply adsorbed on the surfaces without other reactions. The behaviors of Co atoms at the temperature of 100, 200, 300, 400 and 500℃ are observed by STM. As the temperature rising, the Co atoms congregate as islands, and the islands prefer to condense on the edges of islands. Besides, no any evidence shows the Co atoms react with the Si substrate. As the result we conclude that the （ × ）-Ag buffer layer on Si（111）surface can effectively prevent the reaction between Co and Si atoms.
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何淙潤. "Co/Fe/Pt(111)的磁性研究." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/99825348128465104913.
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曾健家. "Fe/Co/Pt(111)的磁性研究." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/42210568056044852049.
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游勝凱. "Co/Ni/Pt(111)的磁性研究." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/91821023658395446153.
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碩士國立臺灣師範大學
物理學系
94
Experiments were performed in situ in a stainless ultrahigh vacuum (UHV) chamber. In situ magneto-optical Kerr effect (MOKE) was used to study the magnetic properties of the system. I study the magnetic properties of ultrathin Co films on Pt(111) with Ni buffer layers. We prepare dCo Co/1 ML Ni/Pt(111), and the Kerr signals measured at room temperature. The polar and longitudinal Kerr signal was not exist for 0 ~ 3 ML Co/1 ML Ni/Pt(111). The easy axis of the magnetization for 4＆5 ML Co/ Pt(111) is in-plane. We find the same result, when dCo Co/1 ML Ni/Pt(111) was prepare at 450K, and the Kerr signals measured at 450K or at room temperature. If we prepare dCo Co/1 ML Ni/Pt(111) at RT, and the Kerr signals measured at 450K. The easy axis of the magnetization for 1 ML Co/ Pt(111) is out-of-plane. The polar and longitudinal Kerr signal was not exist for 2＆3 ML Co/1 ML Ni/Pt(111). The easy axis of the magnetization for 4＆5 ML Co/ Pt(111) is in-plane. The variation of AES of 1 ML Co/1 ML Ni/Pt(111) as a function of sample temperature. We find the mixing of Ni and Co layers occurs at 420K. The formation of Co-Pt alloy causes the perpendicular magnetic anisotropy. I also study the magnetic properties of ultrathin Ni films on Pt(111) with Co buffer layers. The easy axis of the magnetization for 1 ML Co/ Pt(111) is out of plane. We were surprised that only the polar Kerr signals were observed when dNi 24 ML. Studies of the magnetic properties showed that the easy axis of the magnetization changed from the cant to the out-of-plane direction when the Co buffer layer was inserted on Ni/Pt(111). After different temperature annealing, cause the different competition alloy. The competition in the alloy formations between Co-Pt and Ni-Pt in the Co/Ni/Pt(111) and Ni/Co/ Pt(111) system is also interesting, cause the different magnetic properties. I also try to understand that.
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Chang, Yu-Tzu, and 張祐慈. "Research in Canadian co-operative movement：Antigonish Movement（1912-1959）." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/23036518529152084281.
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碩士國立高雄師範大學
成人教育研究所
91
Co-operative movement rooted in 19th century in Europe. It surfaced as a response to changing social conditions. In1844, the Rochdale co-operatives in Britain are supposed to be the most well-known of all the co-operatives. News of these co-operatives spread to Canada through immigrants, reporters and visitors. Many of the conditions that farmers and workers faced in Canada in 20th are similar to those happened in Europe in 19th. Many Canadians believed the co-operative method of dealing business could be employed to solve their social and economic problems. Unique characteristics of co-operatives , and the concern for education makes them different from other economic institutes in society. Especially, Antigonish Movement which took place in1920s in Nova Scotia is honored to be the most outstanding education contribution Canada has made to the world. Primary, the first stage of Antigonish Movement was happened before 1928.Father Jimmy Tompkins was the most important figure. He worked hard and took adult education as a method to help the poors since he was a vice-president of St. Xavier University in 1912. With the establishment of the Extension Department of St. Xavier University at Antigonish in 1928, Moses Michael Coady was appointed as a director. Since then, the movement gained more strength and moved to the second stage. To combine adult education with co-operative movement is the most unique character of Antigonish Movement. Adult education made the humble people gain power ,what’s more is to reflect of themselves and take action to improve their social and economic conditions. The method of adult education used in Antigonish Movement varied. Mass meetings, study clubs, leaders programs and radio studies were parts of them. Especially, mass meetings and study clubs were trademarks of Antigonish Movement for that mass meetings had something to do with perspective transformation, and study clubs were the main educational lever.
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"The immune system and pathogen co-evolution." Thesis, 2010. http://hdl.handle.net/1911/62199.
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A thesis presented on the co-evolution of the immune system and pathogens. The generalized NK (GNK) model is used to describe the fitness landscape upon which the evolution proceeds. Evolution from the scale of viruses to organisms is considered.